自动化专业毕业设计方案中英文翻译

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电气自动化专业毕业设计英文翻译

电气自动化专业毕业设计英文翻译1 Computer structure and functionThis section introduces the internal architecture of a computer and describes how instructions are stored and interpreted and explains how the instruction execution cycle is broken down into its various components.At the most basic level, a computer simply executes binary-coded results. For a general-purpose programmable computer, four necessary elements are the memory, central processing unit (CPU, or simply processor), an external processor bus, and an input/output system as indicated in Fig.3-1 A-1.Fig. 3-1A-1 Basic elements of a computerThe memory stores instructions and data.The CPU reads and interprets the instructions, reads the data required by each instruction, executes the action required by the instruction, and stores the results back in memory. One of the actions that is required of the CPU is to read data from or write data to an external device. This is carried out using the input/output system.The external processor bus is a set of electric conductors that carries data, address and control information between the other computer elements.1-1 The memoryThe memory of a computer consists of a set of sequentially numbered locations. Each location is a register in which binary information can be stored. The “number”of a location is called its address. The lowest address is 0. The manufacturer defines a word length for the processor that is an integral number of locations long. In each word the bits can represent either data or instructions. For the Intel 8086/87 and Motorola MC6800 microprocessors, a word is 16 bits long, but each memory locationhas only 8 bits and thus two 8-bit locations must be accessed to obtain each data word. In order to use the contents of memory, the processor must fetch the contents of the right location. To carry out a fetch, the processor places (enables) the binary-coded address of the desired location onto the address lines of the external processor bus. The memory then allows the contents of the addressed memory location to be read by the processor. The process of fetching the contents of a memory location does not alter the contents of that location.Instructions in memory Instructions stored in memory are fetched by the CPU and unless program branches occur, they are executed in the sequence they appear in memory. An instruction written as a binary pattern is called a machine-language instruction. One way to achieve meaningful patterns is to divide up the bits into fields as indicated in Fig. 3-1A-2, with each field containing a code for a different type of information.0001 0101 1000 XXXX 0100 0001 1000 XXXX 0011 XXXX XXXX 0100 Fields Opcode Immediate code Operand data Branch addressSet ‘5’ in location 8 Subtract ‘1’ f rom location 8 If zero, bran ch to location 416-bit instruction words... ... XXXX : not u sed (or “don ’t care”)Fig. 3-1A-2 Arrangement of program and data in memoryEach instruction in our simple computer can be divided up into four fields of 4 bits each. Each instruction can contain operation code (or opcode, each instruction has a unique opcode), operand address, immediate operands, branch address.In a real instruction set there are many more instructions. There is also a much large number of memory locations in which to store instructions and data. In order to increase the number of memory locations, the address fields and hence theinstructions must be longer than 16 bits if we use the same approach. There are a number of ways to increase the addressing range of the microprocessor without increasing the instruction length: variable instruction field, multiword instructions, multiple addressing modes, variable instruction length. We will not discuss them in detail.Data in memory data is information that is represented in memory as a code. For efficient use of the memory space and processing time, most computers provide the capability of manipulating data of different lengths and representations in memory. The various different representations recognized by the processor are called its data types. The data types normally used are: bit, binary-coded decimal digit (4-bit nibble, BCD), byte (8 bits), word (2 bytes), double word (4 bytes).Some processors provide instructions that manipulate other data types such as single-precision floating-point data types (32bits) and double-precision floating-point data types (64 bits). There is another type of data—character data. It is also usually represented in 8 bits. Each computer terminal key and key combination (such as shift and control functions) on a standard terminal keyboard has a 7-bits code defined by the American Standard Code for Information Interchange (ASCII).Type of memory In the applications of digital control system, we also concerned with the characteristics of different memory techniques. For primary memory, we need it to be stored information temporarily and to be written and got information from successive or from widely different locations. This type memory is called random-access memory (RAM). In some case we do not want the information in memory to be lost. So we are willing to use special techniques to write into memory. If writing is accomplished only once by physically changing connections, the memory is called a read-only memory (ROM). If the interconnection pattern can be programmed to be set, the memory is called a programmable read-only memory (PROM). If rewriting can be accomplished when it is necessary, we have an erasable programmable read-only memory (EPROM). An electronically erasable PROM is abbreviated EEPROM.1-2 The CPUThe CPU’s job is to fetch instructions from memory and execute these instructions. The structure of the CPU is shown in Fig. 3-1A-3. It has four main components: an arithmetic and logical unit (ALU), a set of registers, an internal processor bus and controller.Fig.3-1A-3 Central processing unit (CPU)These and other components of the CPU and their participation in the instruction cycle are described in the following sections.Arithmetic and Logical Unit (ALU) The ALU provides a wide arithmetic operations, including add, subtract, multiply, and divide. It can also perform Boolean logic operations such as AND, OR, and COMPLEMENT on binary data. Other operations, such as word compares, are also available. The majority of computer tasks involve the ALU, but a great amount of data movement is required in order to make use of the ALU instructions.Registers A set of registers inside the CPU in used to store information.Instruction register When an instruction is fetched, it is copied into the instruction register, where it is decoded. Decoding means that the operation code is examined and used to determine the steps of the execution sequence.Programmer’s model of the CPU The collection of registers that can be examined or modified by a programmer is called the programmer’s model of the CPU.The only registers that can be manipulated by the instruction set, or are visibly affected by hardware inputs or the results of operations upon data, are the registers represented in the model.Flag register The execution sequence is determined not only by the instruction but also by the results of the previous instructions. For example, if an addition is carried out in the ALU, data on the result of the addition (whether the result is positive, negative, or zero, for example) is stored in what is known as a flag register, status register, or condition register. If the next instruction is a conditional branch instruction, the flag word is tested in that instruction to determine if a branch if a branch is required.Program counter (instruction pointer)The address of the next instruction is located in a register called the program counter.Data registers When an instruction uses the registers to store data, the reference to the register in the instruction is called register addressing. The reasons of making use of the internal registers to store data are that they can make the instructions shorter and make execution faster.Address registers The internal registers can also be used for the storage of address of data in memory data. In such a case, the instruction word contains a register number (i.e. a register address). In the register is contained the address of memory data to be used in the instruction. This form of addressing is called register indirect addressing. The contents of the register are said to point to the data in memory.Internal Processor Bus The internal processor bus moves data between internal register. A bus is a set of closely grouped electric conductors that transfers data, address, and control information between functional blocks of the CPU. Data from a source register can be passed to a destination register when both are enabled onto (connected to) the bus.Controller The controller provides the proper sequence of control signals for each instruction in a program cycle to be fetched from memory. A total program cycle comprises many instruction cycle, each instruction cycle can be divided up into itscomponent machine cycles and each machine cycle comprises a number of clock cycle.In order to fetch an instruction, for example illustrated in Fig.3-1A-4, the address in the program counter is placed on the address lines of the external bus (AB) at the onset of clock cycle C1. Simultaneously, using a code on the control lines of the bus (CB), the CPU informs all devices attached to the bus that an “opcode” fetch machine cycle is being executed by the CPU. The memory allows the memory address to select the memory location containing the instruction. At C2 the controller places a “read”command onto the control bus which allows the memory data to be placed onto the data bus. The controller then gates the data into the instruction register and removes the read command from the control bus in C3. At C4, the controller removes the address from the address bus and begins to decode the operation-code portion of the instruction to see what steps are required for execution. The decoding operation may take several more clock cycle at the end of which the “opcode fetch” machine cycle.Fig. 3-1A-4 A timing diagram for "operation-code fetch "External attention requests It is often necessary to stop the normal instruction processing sequence. One type of external attention request is the reset request. In thecase of an unrecoverable error, a computer system may be required to reset itself .This would have the effect of initializing all important registers in the system and starting instruction execution from a standard memory location-usually location 0.An input that is more commonly activated during the normal course of events is the interrupt request. An interrupt request signal from an external device can cause the CPU to immediately execute a service subroutine which carries out the necessary actions. After completing the service subroutine, the processor will continue the task from which it was originally interrupted.The third type of input is the bus request, or direct memory access(DMA) request. It is possible to have a terminal interface that stores up all the characters in a line of text until it receives a "carriage return." Then the interface requests the use of the system bus, at which time the complete line of data is transferred to memory as fast as possible. In this way the processor simply becomes inactive until the transfer is completed.1-3 BusesThe bus is the most important communication system in a computer system. Under control of the CPU, a data source device and a data destination device are "enabled" onto(equivalent to being connected to) the bus wires for a short transmission.External processor bus The internal processor bus described in Sec. is connected to the external processor bus by a set of bus buffers located on the microprocessor integrated circuit.System bus The microcomputer board can communicate with other boards by connecting its bus to an external system bus through a connector.1-4Computer Input and OutputA set of registers external to the CPU is associated with what is known as the input/output (I/O) system. The I/O system is connected to the external processor bus using control, address, and data buses through an I/O registers in an interface. There are basically two ways that are used to address I/O register.In the first method, called I/O-mapped input/output, the operation code itself hasspecial I/O instructions that address a numbered register in the interface called an I/O port.The second method of addressing I/O registers gives the I/O ports addresses that lie within the memory address range of the CPU. This is called memory-mapped I/O. Of course there must not be any memory locations at the same address as I/O locations.One of the benefits of the memory-mapped approach is that the full range of memory addressing modes is available to the addressing of I/O registers.2Fundamentals of Computer and Networks2-1 Organization of Computer SystemA computer is a fast and accurate symbol manipulating system that is organized to accept, store, and process data and produce output results under the direction of a stored program of instructions. This section explains why a computer is a system and how a computer system is organized. Key elements in a computer system include input, processing, and output devices. Let's examine each component of the system in more detail.Input Devices Computer system use many devices for input purpose. Some INPUT DEVICES allow direct human/machine communication, while some first require data to be recorded on an input medium such as a magnetizable material. Devices that read data magnetically recorded on specially coated plastic tapes or flexible or floppy plastic disks are popular. The keyboard of a workstation connected directly to (or ONLINE to) a computer is an example of a direct input device. Additional direct input devices include the mouse, input pen, touch screen, and microphone. Regardless of the type of device used, all are components for interpretation and communication between people and computer systems.Central Processing Unit The heart of any computer system is the central processing unit (CPU). There are three main sections found in the CPU of a typical personal computer system: the primary storage section, the arithmetic-logic section,and the control section. But these three sections aren't unique to personal computers. They are found in CPUs of all sizes.Output Device Like input units, output device are instruments of interpretation and communication between humans and computer system of all size. These device take output results from the CPU in machine-coded form and convert them into a form that can be used (a) by people (e.g. a printed and /or displayed report) or (b) as machine input in another processing cycle.In personal computer systems, display screen and desktop printers are popular output devices. Larger and faster printers, many on-line workstations, and magnetic tape drives commonly found in large systems.The input/output and secondary storage units are sometimes called peripheral devices (or just peripherals). This terminology refers to the fact that although these devices are not a part of the CPU, they are often located near it. Besides, a computer system also includes buses, ROM(read only memory), RAM(random access memory), parallel port and serial port, hard disk, floppies and CD(compact disk)drive, and so on.2-2 Operating SystemOperating systems have developed over the past thirty years for two main purposes. First, they provide a convenient environment for the development and execution of programs. Second, operating systems attempt to schedule computational activities to ensure good performance of the computing system.The operating system must ensure correct operation of the computer system. To prevent user programs form interfering with the proper operation of the system, the hardware was modified to create two modes: user mode and monitor mode. Various instructions (such as I/O instructions and halt instructions) are privileged and can only be executed in monitor mode. The memory in which the monitor resides must also be protected from modification by the user. A timer prevents infinite loops. Once these changes (dual mode, privileged instructions, memory protection, timer interrupt) have been made to the basic computer architecture, it is possible to write a correct operating system.As we have stated, operating systems are normally unique to their manufacturers and the hardware in which they are run. Generally, when a new computer system is installed, operational software suitable to that hardware is purchased. Users want reliable operational software that can effectively support their processing activities.Though operational software varies between manufacturers, it has similar characteristics. Modern hardware, because of its sophistication, requires that operating systems meet certain specific standards. For example, considering the present state of the field, an operating system must support some form of on-line processing. Functions normally associated with operational software are:1)Job management;2)Resource management;3)Control of I/O operations4)Error recovery;5)Memory management.2-3 NetworksCommunication between distributed communities of computers is required for many reasons. At a national level, for example, computers located in different parts of the country use public communication services to exchange electronic messages (mail) and to transfer files of information from one computer to another. Similarly, at a local level within, say, a single building, distributed communities of computer-based workstations use local communication networks to access expensive shared resources—for example, printers and disks tapes and copiers, etc.—that are also managed by computers. Clearly, as the range of computer-based products and associated public and local communication networks proliferate, computer-to-computer communication will expand rapidly and ultimately dominate the field of distributed systems.Although the physical separation of the communicating computers may vary considerably from one type of application to another, or, at the heart of any computer communication network is the data communication facility which, may be a PSDN, aprivate LAN or perhaps a number of such networks interconnected together. However, irrespective of the type of data communication facility, an amount of hardware and software is required within each attached computer to handle the appropriate network-dependent protocols. Typically, these are concerned with the establishment of a communication channel access the network and with the control of the flow of messages across this channel. The provision of such facilities is only part of the network requirements, however, since in many applications the communicating computers may be of different forms of data representation interface between user (application) programs, normally referred to as application processes or APs, and the underlying communication services may be different. For example, one computer may be a small single-user computer, while another may be a large multi-user system.3 Stepper motorStepper motor is the electric pulse signals into angular displacement or linear displacement of the open-loop stepper motor control element pieces. In the case of non-overloaded, the motor speed, stop position depends only on the pulse frequency and pulse number, regardless of load changes, when the driver receives a step pulse signal, it will drive a stepper motor to Set the direction of rotation of a fixed angle, called the "step angle", which the angle of rotation is fixed step by step operation. Number of pulses can be controlled by controlling the angular displacement, so as to achieve accurate positioning purposes; the same time by controlling the pulse frequency to control the motor rotation speed and acceleration, to achieve speed control purposes.3-1 WorkInduction motor is a stepper motor, does it work is the use of electronic circuits, the DC power supply into a time-sharing, multi-phase timing control current, this current stepper motor power supply, the stepper motor to work properly , The drive is sharing power supply for the stepper motor, the polyphase timing controller.Although the stepper motor has been widely used, but the stepper motor does notlike a normal DC motor, AC motor in the conventional use. It must be double-ring pulse signal; power driver circuit composed of the control system can be used. Therefore, it is not easy with a good stepping motor, which involves mechanical, electrical, electronics and computers, and much other specialized knowledge.As the stepper motor actuators, electromechanical integration, one of the key products, widely used in a variety of automatic control systems. With the development of microelectronics and computer technology, increasing demand for stepper motor has applications in all areas of the national economy.3-2 CategoriesNow more commonly used include the reaction of step motor stepper motor (VR), permanent magnet stepper motor (PM), hybrid stepper motors (HB) and single-phase stepper motor.3-3 Permanent magnet stepper motorPermanent magnet stepper motor is generally two-phase, torque, and smaller, usually 7.5 degree step angle or 15 degrees;Permanent magnet stepper motor output torque, dynamic performance, but a large step angle.3-4 Reaction Stepper MotorReaction is generally three-phase stepping motor can achieve high torque output, step angle of 1.5 degrees is generally, but the noise and vibration are large. Reaction by the stepper motor rotor magnetic circuit made of soft magnetic materials, a number of the stator phase excitation winding, the use of permeability changes in torque.Step Motor simple structure, low production costs, step angle is small; but the dynamic performance is poor.3-5 Hybrid Stepping MotorHybrid Step Motor combines reactive, permanent magnet stepper motors of both, it's a small step angle, contribute a large, dynamic performance, is currently the highest performance stepper motor. It is also sometimes referred to as PermanentMagnet Induction Stepping Motor. It consists of two phases and the five-phase: the general two-phase step angle of 1.8 degrees and the general five-phase step angle 0.72 degrees. The most widely used Stepper Motor. Stepper motor drive for energy saving 3-6 Three-phase stepper motor drive special features:◆180% low torque output, low frequency characteristics of a good run◆Maximum output frequency 600Hz, high-speed motor control◆full range of detection of protection (over voltage, under voltage, overload)instantaneous power failure restart◆acceleration, deceleration, such as dynamic change in the stall protection functionto prevent◆Electrical dynamic parameters of automatic recognition function to ensurestability and accuracy of the system◆quick response and high-speed shutdown◆abundant and flexible input and output interface and control, versatility◆use of SMT production and three full-mount anti-paint treatment process, productstability and high◆full range of Siemens IGBT power devices using the latest, to ensure the qualityof high-quality3-7 Basic principlesUsually for the permanent magnet rotor motor, when current flows through the stator windings, the stator windings produce a magnetic field vector. The magnetic field will lead to a rotor angle of the magnetic field makes the direction of a rotor and the stator's magnetic field direction. When the stator magnetic field vector rotating at an angle. As the rotor magnetic field is also transferred from another perspective. An electrical pulse for each input, the motor turning a point forward. It is the angular displacement of the output and input the number of pulses proportional to speed and pulse frequency is proportional to. Power to change the order of winding, the motor will reverse. Therefore, the number of available control pulse, frequency and power the motor windings of each phase in order to control the stepper motor rotation.3-8 Induction Stepping Motor3-8-1 features: Induction, compared with the traditional reactive, structural reinforced with a permanent magnet rotor, in order to provide the working point of soft magnetic materials, and the stator excitation magnetic field changes only need to provide to provide the operating point of the consumption of magnetic materials energy, so the motor efficiency, current, low heat. Due to the presence of permanent magnets, the motor has a strong EMF, the damping effect of its own good, it is relatively stable during operation, low noise, low frequency vibration. Induction can be seen as somewhat low-speed synchronous motor. A four-phase motor can be used for four-phase operation, but also can be used for two-phase operation. (Must be bipolar voltage drive), while the motor is not so reactive. For example: four phase, eight-phase operation (A-AB-B-BC-C-CD-D-DA-A) can use two-phase eight-shot run. Not difficult to find the conditions for C =, D =. a two-phase motor's internal winding consistent with the four-phase motors, small power motors are generally directly connected to the second phase, the power of larger motor, in order to facilitate the use and flexible to change the dynamic characteristics of the motor, its external connections often lead to eight (four-phase), so that when used either as a four-phase motors used, can be used for two-phase motor winding in series or parallel.3-8-2 classification：Induction motors can be divided in phases: two-phase motor, three phase motor, four-phase motor, five-phase motor. The frame size (motor diameter) can be divided into: 42BYG (BYG the Induction Stepping motor code), 57BYG, 86BYG, 110BYG, (international standard), and like 70BYG, 90BYG, 130BYG and so are the national standards.3-8-3 the stepper motor phase number of static indicators of terms: very differently on the N, S the number of magnetic field excitation coil. Common m said. Beat number: complete the necessary cyclical changes in a magnetic field pulses or conducting state with n said, or that turned a pitch angle of the motor pulses needed to four-phase motor, for example, a four-phase four-shot operation mode that AB -BC-CD-DA-AB, shot eight four-phase operation mode that A-AB-B-BC-C-CD-D-DA-A. Step angle: corresponds to a pulse signal, the angulardisplacement of the rotor turne d with θ said. θ = 360 degrees (the rotor teeth number of J * run shot), the conventional two, four-phase, the rotor teeth 50 tooth motor as an example. Four step run-time step angle θ = 360 ° / (50 * 4) = 1.8 degrees (commonly called the whole step), eight-shot running step angle θ = 360 ° / (50 * 8) = 0.9 degrees (commonly known as half step.) Location torque: the motor is not energized in the state, its locked rotor torque (as well as by the magnetic field profile of harmonics caused by mechanical error) static torque: the motor under the rated static electricity, the motor without rotation, the motor shaft locking torque. The motor torque is a measure of volume (geometry) standards, and drive voltage and drive power, etc. has nothing to do. Although the static torque is proportional to the electromagnetic magnetizing ampere turns, and fixed air gap between the rotor teeth on, but over-use of reduced air gap, increase the excitation ampere-turns to increase the static torque is not desirable, this will cause the motor heating and mechanical noise.3-9 Characteristics of the stepper motor1. The general accuracy of the stepper motor step angle of 3-5%, and not cumulative.2. Appearance of the stepper motor to allow the maximum temperature.Stepper motor causes the motor temperature is too high the first magnetic demagnetization, resulting in loss of torque down even further, so the motor surface temperature should be the maximum allowed depending on the motor demagnetization of magnetic material points; Generally speaking, the magnetic demagnetization points are above 130 degrees Celsius, and some even as high as 200 degrees Celsius, so the stepper motor surface temperature of 80-90 degrees Celsius is normal.3. Stepper motor torque will decrease with the increase of speed.When the stepper motor rotates, the motor winding inductance of each phase will form a reverse electromotive force; the higher the frequency the greater the back emf. In its role, the motor with frequency (or speed) increases with the phase current decreases, resulting in decreased torque.4. Low-speed stepper motor can operate normally, but if not higher than a certain speed to start, accompanied by howling.。

自动化专业英语原文和翻译

自动化专业英语原文和翻译Title: Original Text and Translation of Automation Professional EnglishIntroduction:In the field of automation, it is essential to have a good command of professional English, as many resources and documents are written in English. In this article, we will explore the original text and translation of automation professional English, providing a comprehensive guide for those looking to improve their language skills in this area.1. Original Text and Translation of Automation Terminology1.1 The original text of automation terminology includes terms such as PLC (Programmable Logic Controller), HMI (Human-Machine Interface), and SCADA (Supervisory Control and Data Acquisition).1.2 The translation of these terms into other languages must be accurate and consistent to ensure clear communication in an international context.1.3 It is important for professionals in the automation industry to be familiar with these terms in both English and their native language to facilitate effective communication with colleagues and clients.2. Original Text and Translation of Automation Standards2.1 Automation standards, such as ISO 9001 and IEC 61131, are crucial for ensuring quality and safety in automation systems.2.2 Translating these standards accurately is essential to ensure compliance with regulations and best practices in different countries.2.3 Professionals in the automation industry should be well-versed in the original text of these standards and their translations to ensure the successful implementation of automation projects worldwide.3. Original Text and Translation of Automation Documentation3.1 Automation documentation, including user manuals, technical specifications, and maintenance guides, is often written in English.3.2 Translating this documentation accurately is essential to ensure that users and technicians can understand and operate automation systems effectively.3.3 Professionals in the automation industry should be proficient in both the original text and translated versions of documentation to facilitate training, troubleshooting, and maintenance of automation systems.4. Original Text and Translation of Automation Research Papers4.1 Research papers on automation topics are often published in English-language journals and conferences.4.2 Translating these papers accurately is crucial for sharing knowledge and advancements in the field of automation with a global audience.4.3 Professionals in the automation industry should be able to read and understand original research papers in English and be familiar with translations in other languages to stay informed about the latest developments in the field.5. Original Text and Translation of Automation Software5.1 Automation software, such as CAD (Computer-Aided Design) and CAM (Computer-Aided Manufacturing) programs, often have interfaces and documentation in English.5.2 Translating this software accurately is essential for ensuring that engineers and technicians can use these tools effectively.5.3 Professionals in the automation industry should be proficient in both the original text and translated versions of automation software to maximize their productivity and efficiency in their work.Conclusion:In conclusion, having a good command of professional English in the field of automation is essential for effective communication, compliance with standards, and staying informed about the latest developments. By understanding the original text and translations of automation terminology, standards, documentation, research papers, and software, professionals in the industry can enhance their language skills and excel in their careers.。

(自动化专业)毕业论文文献翻译中英文对照

(自动化专业)毕业论文文献翻译中英文对照毕业设计外文资料翻译题目可编程控制器技术讨论与未来发展专业电气工程及其自动化PLC technique discussion and future developmentK. Begain, M. ErmelChair for Telecommunications, Dresden University of Technology,01062 Dresden, GermanyAbstract: Programmable Logic Controllers (PLC), a computing device invented by Richard E.Morley in 1968, have been widely used in industry including manufacturing systems, transportation systems, chemical process facilities, and many others. At that time, the PLC placed the hardwired logic with soft-wired logic or so-called relay ladder logic(RLL), a programming language visually resembling the hardwired logic, and reduced thereby the configuration time from 6 months down to 6 days [Moody and Morley,1999].Although PC based control has started to come into place, PLC based control will remain the technique to which the majority of industrial applications will adhere due to its higher performance, lower price, and superior reliability in harsh environments. Moreover, according to a study on the PLC market of Frost and Sullivan [1995], an increase of the annual sales volume to 15 million PLCs per year with the hardware value of more than 8 billion US dollars has been predicted, though the prices of computing hardware is steadily dropping. The inventor of the PLC, Richard E Morley, fairly considers the PLC market as a 5-billion industry at the present time.Key Words：PLC ，performance ，market1 IntroductionAlong with the development of the ages, the technique that is nowadays is also gradually perfect, the competition plays more more strong; the operation that list depends the artificial has already can't satisfied with the current manufacturing industry foreground, also can't guarantee the request of the higher quantity and high new the image of the technique business enterprise.The people see in produce practice, automate brought the tremendous convenience and the product quantities for people up of assurance, also eased the personnel's labor strength, reduce the establishment on the personnel. The target control of the hard realization in many complicated production lines, whole and excellent turn, the best decision etc., well-trained operation work, technical personnel or expert, governor but can judge and operate easily, can acquire the satisfied result. The research target of the artificial intelligence makes use of the calculator exactly to carry out, imitate these intelligences behavior, moderating the work through person's brain and calculators, with the mode that person's machine combine, for resolve the very complicated problem to look for the best pathWe come in sight of the control that links after the electric appliances in various situation, that is already the that time generation past, now of after use in the mold a perhaps simple equipments of grass-roots control that the electric appliances can do for the low level only;And the PLC emergence also became the epoch-making topic, adding the vivid software control through a very and stable hardware, making the automation head for the new high tide.2 PLC characteristics and containment2.1 The PLC biggest characteristicsThe PLC biggest characteristics lie in: The electrical engineering teacher already no longer electric hardware up too many calculationses of cost, as long as order the importation that the button switch or the importation of the sensors order to link the PLC up can solve problem, pass to output to order the conjunction contact machine or control the start equipments of the big power after the electric appliances, but the exportation equipments direct conjunction of the small power can.Figure 1. Open frame PLC2.2 PLC internal containmentPLC internal containment have CPU, and take to have an I/ O for expand of exterior to connect a people's address and saving machine three big pieces to constitute, CPU core is from an or many is tired to add the machine to constitute, mathematics that they have the logic operation ability, and can read the procedure save the contents of the machine to drive the homologous saving machine and I/ Os to connect after pass the calculation; The I/ O add inner part is tired the input and output system of the machine and exterior link, and deposit the related data into the procedure saving machine or data saving machine; The saving machine can deposit the data that the I/ O input in the saving machine, and in work adjusting to become tired to add the machine and I/ Os to connect, saving machine separately saving machine RAM of the procedure saving machine ROM and datas, the ROM can can do deposit of the data permanence in the saving machine, but RAM only for the CPU computes the temporary calculation usage of hour of buffer space.Figure 2. PLC input and output circuits2.3 PLC advantageThe PLC anti- interference is very and excellent, our root need not concern its service life and the work situation bad, these all problems have already no longer become the topic that we fail, but stay to our is a concern to come to internal resources of make use of the PLC to strengthen the control ability of the equipments for us, make our equipments more gentle.PLC language is not we imagine of edit collected materials the language or language of Cs to carry on weaving the distance, but the trapezoid diagram that the adoption is original after the electric appliances to control, make the electrical engineering teacher while weaving to write the procedure very easy comprehended the PLC language, and a lot of non- electricity professional also very quickly know and go deep into to the PLC.3 HMIIs PLC one of the advantage above and only, this is also one part that the people comprehend more and easily, in a lot of equipmentses, the people have already no longer hoped to see too many control buttons, they damage not only and easily and produce the artificial error easiest, small is not a main error perhaps you can still accept; But lead even is a fatal error greatly is what we can't is tolerant of. New technique always for bringing more safe and convenient operation for us, make we a lot of problems for face on sweep but light, do you understand the HMI? Says the HMI here you basically not clear what it is, also have no interest understanding, change one inside text explains it into the touch to hold or man-machine interface you knew, it combines with the PLC to our larger space.HMI the control not only only is reduced the control press button, increase the vivid of the control, more main of it is can sequence of, and at can the change data input to output the feedback with data, control in the temperature curve of imitate but also can keep the manifestation of view to come out. And can write the function help procedure through a plait to provide the help of various what lies in one's power, the one who make operate reduces the otiose error. Currently the HMI factory is also more and more, the function is also more and more strong, the price is also more and more low, the noodles of the usage are wide more and more. The HMI foreground can say that think ° to be good very.4 PLC correspondence and data transmissionAt a lot of situations, the list is is a smooth movement that can't guarantee theequipments by the control of the single machine, but pass the information exchanges of the equipments and equipments to attain the result that we want. For example fore pack and the examination of the empress work preface, we will arrive wrapping information feedback to examine the place, and examine the information of the place to also want the feedback to packing. Pass the information share thus to make both the chain connect, becoming a total body, the match of your that thus make is more close, at each other attain to reflect the result that mutually flick.The PLC correspondence has already come more more body now its value, at the PLC and correspondence between PLCs, can pass the communication of the information and the share of the datas to guarantee that of the equipments moderates mutually, the result that arrive already to repair with each other. Data conversion the adoption RS232 between PLC connect to come to the transmission data, but the RS232 pick up a people and can guarantee 10 meters only of deliver the distance, if in the distance of 1000 meters we can pass the RS485 to carry on the correspondence, the longer distance can pass the MODEL only to carry on deliver.The PLC data transmission is just to be called a form to it in a piece of and continuous address that the data of the inner part delivers the other party, we, the PLC of the other party passes to read data in the watch to carry on the operation. If the data that data in the watch is a to establish generally, that is just the general data transmission, for example today of oil price rise, I want to deliver the price of the oil price to lose the oil ally on board, that is the share of the data; But take data in the watch for an instruction procedure that controls the PLC, that had the difficulty very much, for example you have to control one pedestal robot to press the action work that you imagine, you will draw up for it the form that a procedure combine with the data sends out to pass by.Figure 3. PLC connection with experiments board.4.1 Form of information transmission4.1.1 Simplex and DuplexThe form that information transport contain Simplex, the Half duplex and the Full duplex.The meaning of the Simplex also is to say both, a can send out only, but a can receive only, for example a spy he can receive the designation of the superior only, but can't give the superior reply; Half duplex is also 2 and can can send out similar to accept the data, but can't send out and accept at the same time, for example when you make a phone call is to can't answer the phone, the other party also; But the Half duplex is both can send out and accept the data, and can send out and accept at the same time. Be like the Internet is a typical example.4.1.2 Synchronous and AsynchronousThe process that information transport also has synchronous and asynchronous: The data line and the clock lines are synchronous when synchronous meaning lie in sending out the data, is also the data signal and the clock signals to be carry on by the CPU to send out at the same time, this needs to all want the specialized clock signal each other to carry on the transmission and connect to send, and is constrained, the characteristics of this kind of method lies in its speed very quick, but correspond work time of take up the CPU and also want to be long oppositely, at the same time the technique difficulty also very big. Itsrequest lies in can'ting have an error margins in a datas deliver, otherwise the whole pieceaccording to compare the occurrence mistake, this on the hardware is a bigger difficulty. Applied more and more extensive in some appropriative equipmentses, be like the appropriative medical treatment equipments, the numerical signal equipments...etc., in compare the one data deliver, its result is very good.And asynchronous is an application the most extensive, this receive benefit in it of technique difficulty is opposite and want to be small, at the same time not need to prepare the specialized clock signal, its characteristics to lie in, its data is partition, the long-lost send out and accept, be the CPU is too busy of time can grind to a stop sex to work, also reduced the difficulty on the hardware, the data throw to lose at the same time opposite want to be little, we can pass the examination of the data to observe whether the data that we send out has the mistake or not, be like strange accidentally the method, tired addition and eight efficacies method etc., can use to helps whether the data that we examine to send out have or not the mistake occurrence, pass the feedback to carry on the discriminator.4.1.3 Parallel and SerialA line of transmission of the information contain a string of and combine the cent of: The usual PLC is 8 machines, certainly also having 16 machines. We can be an at the time of sending out the data a send out to the other party, also can be 88 send out the data to the other party, an and 8 differentiationses are also the as that we say to send out the data and combine sends out the data. A speed is more and slowly, but as long as 2 or three lines can solve problem, and can use the telephone line to carry on the long range control. But combine the oscular transmission speed is very quick of, it is a string of oscular of 25600%, occupy the advantage in the short distance, the in view of the fact TTL electricity is even, being limited by the scope of one meter generally, it combine unwell used for the data transmission of the long pull, thus the cost is too expensive.Under a lot of circumstances we are total to like to adopt the string to combine the conversion chip to carry on deliver, under this kind of circumstance not need us to carry on to depositted the machine to establish too and complicatedly, but carry on the data exchanges through the data transmission instruction directly, but is not a very viable way in the correspondence, because the PLC of the other party must has been wait for your data exportation at the time of sending out the data, it can't do other works.4.2 InterruptWhen you are reading the book, you hear someone knock on door, you stop to start up of affair, open the door and combine to continue with the one who knock on door a dialogue, the telephone of this time rang, you signal hint to connect a telephone, afterconnecting the telephone through, return overdo come together knock on door to have a conversation, after dialogue complete, you continue again to see your book, this kind of circumstance we are called the interruption to it, it has the authority, also having sex of have the initiative, the PLC had such function .Its characteristics lie in us and may meet the urgently abrupt affairs in the operation process of the equipments, we want to stop to start immediately up of work, the whereabouts manages the more important affair, this kind of circumstance is we usually meet of, PLC while carry out urgent mission, total will keep the current appearance first, for example the address of the procedure, CPU of tired add the machine data etc., be like to to stick down which the book that we see is when we open the door the page or simply make a mark, because we treat and would still need to continue immediately after book of see the behind. The CPU always does the affair that should do according to our will, but your mistake of give it an affair, it also would be same to do, this we must notice.The interruption is not only a, sometimes existing jointly with the hour several inside break, break off to have the preferred Class, they will carry out the interruption of the higher Class according to person's request. This kind of breaks off the medium interruption to also became to break off the set. The Class that certainly break off is relevant according to various resources of CPU with internal PLC, also following a heap of capacity size of also relevant fasten.The contents that break off has a lot of kinds, for example the exterior break off, correspondence in of send out and accept the interruption and settle and the clock that count break off, still have the WDT to reset the interruption etc., they enriched the CPU to respond to the category while handle various business. Speak thus perhaps you can't comprehend the internal structure and operation orders of the interruption completely also, we do a very small example to explain.4.3 Emergency stop buttonEach equipments always will not forget a button, it also is at we meet the urgent circumstance use of, that is nasty to stop the button. When we meet the Human body trouble and surprised circumstances we as long as press it, the machine stops all operations immediately, and wait for processing the over surprised empress recover the operation again.Nasty stop the internal I/ O of the internal CPU of the button conjunction PLC to connect up, be to press button an exterior to trigger signal for CPU, the CPU carries on to the I/ O to examine again, being to confirm to have the exterior to trigger the signal, CPU protection the spot breaks off procedure counts the machine turn the homologous exteriorI/ O automatically in the procedure to go to also, be exterior interruption procedure processing complete, the procedure counts the machine to return the main procedure to continue to work.Have 1:00 can what to explain is we generally would nasty stop the button of exterior break off to rise to the tallest Class, thus guarantee the safety.4.4 PLC Counting functionWhen we are work a work piece, giving the PLC a signal, counting PLC inner part the machine add 1 to compute us for a day of workload, a count the machine and can solve problem in brief, certainly they also can keep the data under the condition of dropping the electricity, urging the data not to throw to lose, this is also what we hope earnestly.The PLC still has the function that the high class counts the machine, being us while accept some datas of high speed, the high speed that here say is the data of the in all aspects tiny second class, for example the bar code scanner is scanning the data continuously, calculating high-speed signal of the data processor DSP etc., we will adopt the high class to count the machine to help we carry on count. It at the PLC carries out the procedure once discover that the high class counts the machine to should of interruption, will let go of the work on the hand immediately. The trapezoid diagram procedure that passes by to weave the distance again explains the high class for us to carry out procedure to count machine would automatic performance to should of work, thus rise the Class that the high class counts the machine to high one Class.You heard too many this phrases perhaps:" crash", the meaning that is mostly is a workload of CPU to lead greatly, the internal resources shortage etc. the circumstance can't result in procedure circulate. The PLC also has the similar circumstance, there is a watchdog WDT in the inner part of PLC, we can establish time that a procedure of WDT circulate, being to appear the procedure to jump to turn the mistake in the procedure movement process or the procedure is busy, movement time of the procedure exceeds WDT constitution time, the CPU turn but the WDT reset the appearance. The procedure restarts the movement, but will not carry on the breakage to the interruption.Figure 4. Overall board design.5 PLC development in the futureThe PLC development has already entered for network ages of correspondence from the mode of the one, and together other works control the net plank and I/ O card planks to carry on the share easily. A state software can pass all se hardwares link, more animation picture of keep the view to carries on the control, and cans pass the Internet to carry on the control in the foreign land, the blast-off that is like the absolute being boat No.5 is to adopt this kind of way to make airship go up the sky.The development of the higher layer needs our continuous effort to obtain.The PLC emergence has already affected a few persons fully, we also obtained more knowledge and precepts from the top one experience of the generation, coming to the continuous development PLC technique, push it toward higher wave tide.References[1] R. Alur, C. Courcoubetis, and D. Dill. Model-Checking for Real-Time Systems.In Fifth Annual IEEE Symp. on Logic in Computer Science, pages 414{425.IEEE Press, 1990. [2] R. Alur and D.L. Dill. A theory of timed automata. Theoret. Comput. Sci.,126:183{235, 1994.[3] R. Alur, T. Henzinger, and E. Sontag, editors. Hybrid Systems III, volume 1066 of Lecture Notes in Computer Science. Springer-Verlag, 1996.[4] J. Bengtsson, K.G. Larsen, F. Larsson, P. Pettersson, and Wang Yi. Uppaal {a ToolSuite for Automatic Verification of Real-Time Systems. In Alur et al.[3]. 232{243.[5] D. Bosscher, I. Polak, and F. Vaandrager. Verification of an Audio Control Protocol. InH. Langmaack, W.-P. de Roever, and J. Vytopil, editors, Formal Techniques in Real-Time and Fault-Tolerant Systems, volume 863 of Lecture Notes in Computer Science, pages 170{192. Springer-Verlag, 1994.PLC technique discussion and future development, 2010, 130(9): 2436-2443.可编程控制器技术讨论与未来发展K.培根, M. 厄米尔通信教授, 德累斯顿科技大学,01062德累斯顿，德国摘要可编程逻辑控制器（PLC）是Richard E.Morley在1968年发明的一种具备运算功能的设备，现已被广泛的应用到工业中，包括制造系统、交通系统、化工过程设备等。

电气工程与自动化毕业论文中英文资料外文翻译

电气工程与自动化毕业论文中英文资料外文翻译The Transformer on load ﹠Introduction to DC MachinesIt has been shown that a primary input voltage 1V can be transformed to any desired open-circuit secondary voltage 2E by a suitable choice of turns ratio. 2E is available for circulating a load current impedance. For the moment, a lagging power factor will be considered. The secondary current and the resulting ampere-turns 22N I will change the flux, tending to demagnetize the core, reduce m Φ and with it 1E . Because the primary leakage impedance drop is so low, a small alteration to 1Ewill cause an appreciable increase of primary current from 0I to a new value of 1Iequal to ()()i jX R E V ++111/. The extra primary current and ampere-turns nearly cancel the whole of the secondary ampere-turns. This being so , the mutual flux suffers only a slight modification and requires practically the same net ampere-turns 10N I as on no load. The total primary ampere-turns are increased by an amount 22N I necessary to neutralize the same amount of secondary ampere-turns. In thevector equation , 102211N I N I N I =+; alternatively, 221011N I N I N I -=. At full load,the current 0I is only about 5% of the full-load current and so 1I is nearly equalto 122/N N I . Because in mind that 2121/N N E E =, the input kV A which is approximately 11I E is also approximately equal to the output kV A, 22I E .The physical current has increased, and with in the primary leakage flux towhich it is proportional. The total flux linking the primary ,111Φ=Φ+Φ=Φm p , isshown unchanged because the total back e.m.f.,（dt d N E /111Φ-）is still equal and opposite to 1V . However, there has been a redistribution of flux and the mutual component has fallen due to the increase of 1Φ with 1I . Although the change is small, the secondary demand could not be met without a mutual flux and e.m.f.alteration to permit primary current to change. The net flux s Φlinking thesecondary winding has been further reduced by the establishment of secondaryleakage flux due to 2I , and this opposes m Φ. Although m Φ and 2Φ are indicatedseparately , they combine to one resultant in the core which will be downwards at theinstant shown. Thus the secondary terminal voltage is reduced to dt d N V S /22Φ-=which can be considered in two components, i.e. dt d N dt d N V m //2222Φ-Φ-=orvectorially 2222I jX E V -=. As for the primary, 2Φ is responsible for a substantiallyconstant secondary leakage inductance222222/Λ=ΦN i N . It will be noticed that the primary leakage flux is responsible for part of the change in the secondary terminal voltage due to its effects on the mutual flux. The two leakage fluxes are closely related; 2Φ, for example, by its demagnetizing action on m Φ has caused the changes on the primary side which led to the establishment of primary leakage flux.If a low enough leading power factor is considered, the total secondary flux and the mutual flux are increased causing the secondary terminal voltage to rise with load. p Φ is unchanged in magnitude from the no load condition since, neglecting resistance, it still has to provide a total back e.m.f. equal to 1V . It is virtually the same as 11Φ, though now produced by the combined effect of primary and secondary ampere-turns. The mutual flux must still change with load to give a change of 1E and permit more primary current to flow. 1E has increased this time but due to the vector combination with 1V there is still an increase of primary current.Two more points should be made about the figures. Firstly, a unity turns ratio has been assumed for convenience so that '21E E =. Secondly, the physical picture is drawn for a different instant of time from the vector diagrams which show 0=Φm , if the horizontal axis is taken as usual, to be the zero time reference. There are instants in the cycle when primary leakage flux is zero, when the secondary leakage flux is zero, and when primary and secondary leakage flux is zero, and when primary and secondary leakage fluxes are in the same sense.The equivalent circuit already derived for the transformer with the secondary terminals open, can easily be extended to cover the loaded secondary by the addition of the secondary resistance and leakage reactance.Practically all transformers have a turns ratio different from unity although such an arrangement is sometimes employed for the purposes of electrically isolating one circuit from another operating at the same voltage. To explain the case where 21N N ≠ the reaction of the secondary will be viewed from the primary winding. The reaction is experienced only in terms of the magnetizing force due to the secondary ampere-turns. There is no way of detecting from the primary side whether 2I is large and 2N small or vice versa, it is the product of current and turns which causesthe reaction. Consequently, a secondary winding can be replaced by any number of different equivalent windings and load circuits which will give rise to an identical reaction on the primary .It is clearly convenient to change the secondary winding to an equivalent winding having the same number of turns 1N as the primary.With 2N changes to 1N , since the e.m.f.s are proportional to turns, 2212)/('E N N E = which is the same as 1E .For current, since the reaction ampere turns must be unchanged 1222'''N I N I = must be equal to 22N I .i.e. 2122)/(I N N I =.For impedance , since any secondary voltage V becomes V N N )/(21, and secondary current I becomes I N N )/(12, then any secondary impedance, including load impedance, must becomeI V N N I V /)/('/'221=. Consequently,22212)/('R N N R = and 22212)/('X N N X = . If the primary turns are taken as reference turns, the process is called referring to the primary side.There are a few checks which can be made to see if the procedure outlined is valid.For example, the copper loss in the referred secondary winding must be the same as in the original secondary otherwise the primary would have to supply a differentloss power. ''222R I must be equal to 222R I . ）222122122/()/(N N R N N I •• does infact reduce to 222R I .Similarly the stored magnetic energy in the leakage field)2/1(2LI which is proportional to 22'X I will be found to check as ''22X I . The referred secondary 2212221222)/()/(''I E N N I N N E I E kVA =•==.The argument is sound, though at first it may have seemed suspect. In fact, if the actual secondary winding was removed physically from the core and replaced by the equivalent winding and load circuit designed to give the parameters 1N ,'2R ,'2X and '2I , measurements from the primary terminals would be unable to detect any difference in secondary ampere-turns, kVA demand or copper loss, under normal power frequency operation.There is no point in choosing any basis other than equal turns on primary andreferred secondary, but it is sometimes convenient to refer the primary to the secondary winding. In this case, if all the subscript 1’s are interchanged for the subscript 2’s, the necessary referring constants are easily found; e.g. 2'1R R ≈,21'X X ≈; similarly 1'2R R ≈ and 12'X X ≈.The equivalent circuit for the general case where 21N N ≠ except that m r hasbeen added to allow for iron loss and an ideal lossless transformation has been included before the secondary terminals to return '2V to 2V .All calculations of internal voltage and power losses are made before this ideal transformation is applied. The behaviour of a transformer as detected at both sets of terminals is the same as the behaviour detected at the corresponding terminals of this circuit when the appropriate parameters are inserted. The slightly different representation showing the coils 1N and 2N side by side with a core in between is only used for convenience. On the transformer itself, the coils are , of course , wound round the same core.Very little error is introduced if the magnetising branch is transferred to the primary terminals, but a few anomalies will arise. For example ,the current shown flowing through the primary impedance is no longer the whole of the primary current.The error is quite small since 0I is usually such a small fraction of 1I . Slightlydifferent answers may be obtained to a particular problem depending on whether or not allowance is made for this error. With this simplified circuit, the primary and referred secondary impedances can be added to give:221211)/(Re N N R R += and 221211)/(N N X X Xe +=It should be pointed out that the equivalent circuit as derived here is only valid for normal operation at power frequencies; capacitance effects must be taken into account whenever the rate of change of voltage would give rise to appreciablecapacitance currents, dt CdV I c /=. They are important at high voltages and atfrequencies much beyond 100 cycles/sec. A further point is not the only possible equivalent circuit even for power frequencies .An alternative , treating the transformer as a three-or four-terminal network, gives rise to a representation which is just as accurate and has some advantages for the circuit engineer who treats all devices as circuit elements with certain transfer properties. The circuit on this basiswould have a turns ratio having a phase shift as well as a magnitude change, and the impedances would not be the same as those of the windings. The circuit would not explain the phenomena within the device like the effects of saturation, so for an understanding of internal behaviour .There are two ways of looking at the equivalent circuit:(a) viewed from the primary as a sink but the referred load impedance connected across '2V ,or(b) viewed from the secondary as a source of constant voltage 1V with internal drops due to 1Re and 1Xe . The magnetizing branch is sometimes omitted in this representation and so the circuit reduces to a generator producing a constant voltage 1E (actually equal to 1V ) and having an internal impedance jX R + (actually equal to 11Re jXe +).In either case, the parameters could be referred to the secondary winding and this may save calculation time .The resistances and reactances can be obtained from two simple light load tests. Introduction to DC MachinesDC machines are characterized by their versatility. By means of various combination of shunt, series, and separately excited field windings they can be designed to display a wide variety of volt-ampere or speed-torque characteristics for both dynamic and steadystate operation. Because of the ease with which they can be controlled , systems of DC machines are often used in applications requiring a wide range of motor speeds or precise control of motor output.The essential features of a DC machine are shown schematically. The stator has salient poles and is excited by one or more field coils. The air-gap flux distribution created by the field winding is symmetrical about the centerline of the field poles. This axis is called the field axis or direct axis.As we know , the AC voltage generated in each rotating armature coil is converted to DC in the external armature terminals by means of a rotating commutator and stationary brushes to which the armature leads are connected. The commutator-brush combination forms a mechanical rectifier, resulting in a DCarmature voltage as well as an armature m.m.f. wave which is fixed in space. The brushes are located so that commutation occurs when the coil sides are in the neutral zone , midway between the field poles. The axis of the armature m.m.f. wave then in 90 electrical degrees from the axis of the field poles, i.e., in the quadrature axis. In the schematic representation the brushes are shown in quarature axis because this is the position of the coils to which they are connected. The armature m.m.f. wave then is along the brush axis as shown.. (The geometrical position of the brushes in an actual machine is approximately 90 electrical degrees from their position in the schematic diagram because of the shape of the end connections to the commutator.)The magnetic torque and the speed voltage appearing at the brushes are independent of the spatial waveform of the flux distribution; for convenience we shall continue to assume a sinusoidal flux-density wave in the air gap. The torque can then be found from the magnetic field viewpoint.The torque can be expressed in terms of the interaction of the direct-axis air-gapflux per pole d Φ and the space-fundamental component 1a F of the armature m.m.f.wave . With the brushes in the quadrature axis, the angle between these fields is 90 electrical degrees, and its sine equals unity. For a P pole machine 12)2(2a d F P T ϕπ=In which the minus sign has been dropped because the positive direction of thetorque can be determined from physical reasoning. The space fundamental 1a F ofthe sawtooth armature m.m.f. wave is 8/2π times its peak. Substitution in above equation then givesa d a a d a i K i m PC T ϕϕπ==2 Where a i =current in external armature circuit;a C =total number of conductors in armature winding;m =number of parallel paths through winding;Andm PC K aa π2=Is a constant fixed by the design of the winding.The rectified voltage generated in the armature has already been discussedbefore for an elementary single-coil armature. The effect of distributing the winding in several slots is shown in figure ,in which each of the rectified sine waves is the voltage generated in one of the coils, commutation taking place at the moment when the coil sides are in the neutral zone. The generated voltage as observed from the brushes is the sum of the rectified voltages of all the coils in series between brushesand is shown by the rippling line labeled a e in figure. With a dozen or socommutator segments per pole, the ripple becomes very small and the average generated voltage observed from the brushes equals the sum of the average values ofthe rectified coil voltages. The rectified voltage a e between brushes, known also asthe speed voltage, ism d a m d a a W K W m PC e ϕϕπ==2 Where a K is the design constant. The rectified voltage of a distributed winding has the same average value as that of a concentrated coil. The difference is that the ripple is greatly reduced.From the above equations, with all variable expressed in SI units:m a a Tw i e =This equation simply says that the instantaneous electric power associated with the speed voltage equals the instantaneous mechanical power associated with the magnetic torque , the direction of power flow being determined by whether the machine is acting as a motor or generator.The direct-axis air-gap flux is produced by the combined m.m.f. f f i N ∑ of the field windings, the flux-m.m.f. characteristic being the magnetization curve for the particular iron geometry of the machine. In the magnetization curve, it is assumed that the armature m.m.f. wave is perpendicular to the field axis. It will be necessary to reexamine this assumption later in this chapter, where the effects of saturation are investigated more thoroughly. Because the armature e.m.f. is proportional to flux times speed, it is usually more convenient to express the magnetization curve in termsof the armature e.m.f. 0a e at a constant speed 0m w . The voltage a e for a given fluxat any other speed m w is proportional to the speed,i.e. 00a m m a e w w e =Figure shows the magnetization curve with only one field winding excited. This curve can easily be obtained by test methods, no knowledge of any design details being required.Over a fairly wide range of excitation the reluctance of the iron is negligible compared with that of the air gap. In this region the flux is linearly proportional to the total m.m.f. of the field windings, the constant of proportionality being the direct-axis air-gap permeance.The outstanding advantages of DC machines arise from the wide variety of operating characteristics which can be obtained by selection of the method of excitation of the field windings. The field windings may be separately excited from an external DC source, or they may be self-excited; i.e., the machine may supply its own excitation. The method of excitation profoundly influences not only the steady-state characteristics, but also the dynamic behavior of the machine in control systems.The connection diagram of a separately excited generator is given. The required field current is a very small fraction of the rated armature current. A small amount of power in the field circuit may control a relatively large amount of power in the armature circuit; i.e., the generator is a power amplifier. Separately excited generators are often used in feedback control systems when control of the armature voltage over a wide range is required. The field windings of self-excited generators may be supplied in three different ways. The field may be connected in series with the armature, resulting in a shunt generator, or the field may be in two sections, one of which is connected in series and the other in shunt with the armature, resulting in a compound generator. With self-excited generators residual magnetism must be present in the machine iron to get the self-excitation process started.In the typical steady-state volt-ampere characteristics, constant-speed primemovers being assumed. The relation between the steady-state generated e.m.f. a Eand the terminal voltage t V isa a a t R I E V -=Where a I is the armature current output and a R is the armature circuitresistance. In a generator, a E is large than t V ; and the electromagnetic torque T is acountertorque opposing rotation.The terminal voltage of a separately excited generator decreases slightly with increase in the load current, principally because of the voltage drop in the armature resistance. The field current of a series generator is the same as the load current, so that the air-gap flux and hence the voltage vary widely with load. As a consequence, series generators are not often used. The voltage of shunt generators drops off somewhat with load. Compound generators are normally connected so that the m.m.f. of the series winding aids that of the shunt winding. The advantage is that through the action of the series winding the flux per pole can increase with load, resulting in a voltage output which is nearly constant. Usually, shunt winding contains many turns of comparatively heavy conductor because it must carry the full armature current of the machine. The voltage of both shunt and compound generators can be controlled over reasonable limits by means of rheostats in the shunt field. Any of the methods of excitation used for generators can also be used for motors. In the typical steady-state speed-torque characteristics, it is assumed that the motor terminals are supplied froma constant-voltage source. In a motor the relation between the e.m.f. a E generated inthe armature and the terminal voltage t V isa a a t R I E V +=Where a I is now the armature current input. The generated e.m.f. a E is nowsmaller than the terminal voltage t V , the armature current is in the oppositedirection to that in a motor, and the electromagnetic torque is in the direction to sustain rotation of the armature.In shunt and separately excited motors the field flux is nearly constant. Consequently, increased torque must be accompanied by a very nearly proportional increase in armature current and hence by a small decrease in counter e.m.f. to allow this increased current through the small armature resistance. Since counter e.m.f. is determined by flux and speed, the speed must drop slightly. Like the squirrel-cage induction motor ,the shunt motor is substantially a constant-speed motor having about 5 percent drop in speed from no load to full load. Starting torque and maximum torque are limited by the armature current that can be commutatedsuccessfully.An outstanding advantage of the shunt motor is ease of speed control. With a rheostat in the shunt-field circuit, the field current and flux per pole can be varied at will, and variation of flux causes the inverse variation of speed to maintain counter e.m.f. approximately equal to the impressed terminal voltage. A maximum speed range of about 4 or 5 to 1 can be obtained by this method, the limitation again being commutating conditions. By variation of the impressed armature voltage, very wide speed ranges can be obtained.In the series motor, increase in load is accompanied by increase in the armature current and m.m.f. and the stator field flux (provided the iron is not completely saturated). Because flux increases with load, speed must drop in order to maintain the balance between impressed voltage and counter e.m.f.; moreover, the increase in armature current caused by increased torque is smaller than in the shunt motor because of the increased flux. The series motor is therefore a varying-speed motor with a markedly drooping speed-load characteristic. For applications requiring heavy torque overloads, this characteristic is particularly advantageous because the corresponding power overloads are held to more reasonable values by the associated speed drops. Very favorable starting characteristics also result from the increase in flux with increased armature current.In the compound motor the series field may be connected either cumulatively, so that its.m.m.f.adds to that of the shunt field, or differentially, so that it opposes. The differential connection is very rarely used. A cumulatively compounded motor has speed-load characteristic intermediate between those of a shunt and a series motor, the drop of speed with load depending on the relative number of ampere-turns in the shunt and series fields. It does not have the disadvantage of very high light-load speed associated with a series motor, but it retains to a considerable degree the advantages of series excitation.The application advantages of DC machines lie in the variety of performance characteristics offered by the possibilities of shunt, series, and compound excitation. Some of these characteristics have been touched upon briefly in this article. Stillgreater possibilities exist if additional sets of brushes are added so that other voltages can be obtained from the commutator. Thus the versatility of DC machine systems and their adaptability to control, both manual and automatic, are their outstanding features.中文翻译负载运行的变压器及直流电机导论通过选择合适的匝数比，一次侧输入电压1V 可任意转换成所希望的二次侧开路电压2E 。

自动化专业英文文献翻译2

西南交通大学毕业设计（英文翻译）节能型机房温湿度远程控制系统测控节点设计年级:学号:姓名:专业:指导老师:二零一一年六月MosixMosix修改bsdi上的BSD/ OS来提供电脑上的跨网络的动态负载平衡组和先发制人进程迁移。

这是不错的东西，不只是为并行处理，但对于通常使用一个集群很像一个可扩展的SMP。

是否有Linux版本？详细信息，请看.cs.huji.ac.il/mosix/。

NOW (工作站网络)伯克利工作站网络项目，/，已经极大地推广了并行计算中使用工作站网络，这里还有很多工作在进行中，都致力于“在未来几年内展示一个实际的100处理器系统”。

唉，他们不使用linux。

并行处理使用linux并行处理使用Linux 站点，/LDP/,是这些指南和许多相关文件包括为全日制量身订造的在线幻灯片的家园。

除了在报纸项目上，普渡大学电机与计算机工程系已经是并行处理的领先者，这个的设立是为了帮助别人申请并行处理的Linux电脑。

自从普渡大学的第一组Linux个人电脑在1994年2月组装以来，已经诞生了许多的Linux PC集群，有些还包括视频墙。

然而这些集群使用386，486和奔腾系统（没有奔腾Pro系统），英特尔最近获得普渡大学的捐赠，将允许它的奔腾II系统构建多个大型集群（与单个群集计划多达165机）。

并且这些集群都将有论文网，也具有最传统的网络。

奔腾Pro集群研讨会1997年，4月10-11日，埃姆斯实验室在得梅因，爱荷华州举行了奔腾Pro集群研讨会。

在本次研讨会，/workshops/PPCworkshop.html，从云集的参加者中收集了很多丰富的PC集群信息。

TreadMarks帝斯曼(分布式共享内存)帝斯曼（分布式共享内存）是一种技术，即一个消息传递系统可以出现的行为作为一个SMP。

有不少这样的系统，其中大部分使用OS页故障触发消息传输机制。

TreadMarks，/~willy/TreadMarks/overview.html，是这种系统更有效地之一，并在Linux集群上运行。

自动化毕业设计英文翻译

自动化毕业设计英文翻译Automatic Graduation Project TranslationIntroductionIn today's fast-paced world, automation has become an integral part of various industries. It has revolutionized the way we work and has significantly improved efficiency and productivity. As a result, automation has become a popular choice for graduation projects among engineering students. In this article, we will delve into the topic of automatic graduation project translation and explore its significance and benefits.The Significance of Automatic Graduation Project TranslationAutomatic graduation project translation refers to the use of automated tools and techniques to translate project documentation and reports from one language to another. This process eliminates the need for manual translation, saving time and effort for students. Moreover, it ensures accuracy and consistency in the translation, reducing the risk of misinterpretation.Benefits of Automatic Graduation Project Translation1. Time-saving: Manual translation can be a time-consuming task, especially when dealing with lengthy project documents. By utilizing automatic translation tools, students can significantly reduce the time spent on translation, allowing them to focus on other important aspects of their project.2. Improved accuracy: Automated translation tools use advanced algorithms and machine learning techniques to ensure accurate translations. These tools havethe ability to learn from previous translations and improve their accuracy over time. This reduces the chances of errors and ensures the quality of the translated content.3. Cost-effective: Hiring professional translators can be expensive, especially for students on a limited budget. Automatic translation tools provide a cost-effective solution, as they are often available for free or at a minimal cost. This allows students to allocate their resources efficiently and invest in other project requirements.4. Enhanced collaboration: Automatic translation tools facilitate seamless collaboration among team members who may speak different languages. By translating project documentation, everyone can understand and contribute to the project without any language barriers. This promotes effective teamwork and improves overall project outcomes.Challenges and LimitationsWhile automatic graduation project translation offers numerous benefits, it is important to acknowledge its challenges and limitations. Some of these include: 1. Language nuances: Automated translation tools may struggle to accurately capture the nuances and subtleties of a language. This can result in the loss of context and potential misinterpretation of the translated content. Therefore, it is crucial for students to review and edit the translated material to ensure its accuracy.2. Technical jargon: Engineering projects often involve complex technical jargonand terminology. Automated translation tools may not have the capability to accurately translate these specialized terms. Students must be cautious and manually review the translated content to ensure the technical accuracy of their project documentation.3. Cultural differences: Different cultures have unique ways of expressing ideas and concepts. Automated translation tools may not always be able to capture these cultural nuances, leading to misunderstandings or misinterpretations. Students should be aware of these differences and make necessary adjustments to ensure effective communication.ConclusionAutomatic graduation project translation offers students a convenient and efficient way to translate project documentation. It saves time, improves accuracy, and promotes collaboration among team members. However, it is important to recognize the limitations of automated translation tools and take necessary precautions to ensure the quality and accuracy of the translated content. By leveraging the benefits of automatic translation while being mindful of its limitations, students can enhance their graduation projects and contribute to the advancement of automation in the engineering field.。

自动化专业毕业设计外文翻译--现地控制单元在水电厂自动化中的应用

英文资料及翻译Location Control Unit In Hydroelectric PowerPlant Automation Application1. ForewordThe hydraulic electricity generation compares with burns coal, the fuel oil, the nuclear power electricity generation, the energy is renewable, the never exhaustible clean energy. The country gives priority to development the hydraulic electricity generation achievement to do well at present the energy balance the strategic measure, and appeared a row measure to encourage to advance the hydroelectric power plant construction vigorously. In the water and electricity profession, was on duty " along with hydroelectric power plant " nobody (few person value to defend) and the condition overhaul work thoroughly develops unceasingly, adds water the power plant production to move and to manage set a higher request; “Separated take the factory net, competes the price to access the net” also adds water as the foundation electric power system reform the power plant automation technology to set the new request. Computer technology, information technology, networking, industry control technology rapid development, for hydroelectric power plant synthesis automated system regardless of in the structure in the function, has all provided a broad development space.The 70's intermediate stages, the overseas hydroelectric power plant starts the advanced computer technology to apply in the hydro-electric power station industrial control, raised the hydroelectric power plant automated level greatly, has obtained the good economic efficiency. At the end of the 70's, the original electric power department science and technology committee managed held “the national hydroelectric power plant automation technical background meeting”, formulated the hydroelectric power plant automation science and technology to develop 7 years plan, our country starts to introduce and the domestic independent research and development hydroelectric power plant computer supervisory system technology and to obtain the huge success. Through many year endeavors, the domestic independent development hydroelectric power plant automation technology development experienced had tried to find out, the experiment site, the promotion, enhanced these four stages, has obtained the very big result. In the recent 20 years, the domestic hydroelectric power plant automation level development are specially rapid, at present entered the world advanced ranks.The hydroelectric power plant computer supervisory system usually may divide into two major parts, one is carries on the common control to the entire factory equipment the part, calls it the factory level or the factory station level supervisory system; Another part is located the water wheel electricity generation level, the switching house and so on the equipment nearby control sections, is called the location control system. The location control system main constituent is location control unit LCU (Local Control Unit), the early on once has used with electrical network dispatch remote terminal RTU (Remote Terminal Unit) the similar name, considered LCU the meaning is more accurate, since 1991 “location control unit academic conference”, basically unifies calls it LCU. Now makes several discussions on LCU in Our country Hydroelectric powerplant automated system application and the development.2. LCU applicationIn the hydroelectric power plant computer supervisory system LCU with the power plant production process connection, is directly in the system most has the object-oriented distribution characteristic the control device. The location control unit controlled member mainly includes following several parts:(1) power plant generating set, mainly has the hydraulic turbine, the generator, the auxiliary engine, the transformer and so on;(2) switching house, mainly has the generatrix, the circuit breaker, the isolator, the earth knife switch and so on;(3) public utility, mainly has the factory to use electricity the system, the oil system, the aqueous system, the direct current system and so on;(4) strobe, mainly has the water inlet strobe, the flood discharge strobe and so on.The LCU general arrangement nearby the power plant production equipment, to is accused the object movement operating mode to carry on the real-time surveillance and the control, is the power plant computer supervisory system compares the first floor control section. The primary data carries on gathering and the pretreatment in this, each kind of control adjustment order all sends out and completes the control closed loop through it, it is in the entire supervisory system very important, to the reliable request very high control device. Uses in the hydroelectric power plant LCU may divide into unit LCU, public LCU, switching house LCU according to the monitoring object and the installment position and so on. But and disposes according to the LCU itself structure divides, then may divide into the single trigger --linear structure LCU, take programmable controller (PLC) as foundation LCU, the intelligent location controller and so on three kinds. First kind of LCU many for hydroelectric power plant automation initial period product, at present basic no longer has used in the new system. Moreover still had few small hydroelectric power plants to use based on industry PC machine (called labor controlled machine IPC) the control system, below only discussed is in the mainstream status PLC and the intelligent location controller (the recent several years still had is called PCC (Programmable Computer Controller), PAC (Programmable Automation Controller) product, should also be possible to classify).2.1 programmable controller (PLC)The PLC definition has many kinds. International electrician committee (IEC) to PLC the definition is: The programmable controller is one kind of digital operation electronic system, for designs specially in the industry environment application. It uses the programmable the memory, uses in its internally stored program, carries out the logic operation, the sequential control, fixed time, counts with the arithmetic operation and so on face user's instruction, and through digital, the simulation input and the output, controls each kind of type the machinery or the production process. The programmable controller and the related equipment, all should according to easy form a whole with the industry control system, easy to expand its function the principle design.At first, needed to produce as a result of the American automobile industry has been possible to say was primitive PLC. Although the PLC being published time does not calculate long too, but along with the microprocessor appearance, large-scale, the ultra large scale integrated circuit technique of manufacture and the data communication technology rapid development, the PLC application and the technology also obtained the rapid development, its developing processapproximately separable three stages:(1) early time PLC (at the end of 60's -70's intermediate stages): Early PLC is called the programmable logical controller generally.(2) intermediate stage PLC (in 70's intermediate stage - 80's, later period): Starts in the 70's to use the microprocessor to take PLC the central processing element (CPU). Thus, causes PLC to result in the function big enhancement. In the software aspect, in the original logic operation, fixed time, counted and so on in the function foundations to increase functions and so on arithmetic operation, data processing and data communication, from diagnosis. In the hardware aspect, has developed the simulation quantity module, the long-distance I/O module as well as each kind of special function module, enables PLC the application scope to expand rapidly to needs the automatic control very many professions.(3) near future PLC (in the 80's, later period until now) enters in for the 80's, the later period, because the microprocessor hardware technique of manufacture rapid development, simultaneously the market price large scale drop, will cause each PLC manufacturer to be possible to use a higher scale the microprocessor. In order to further enhance PLC the processing speed, the very many manufacture manufacturer also developed has developed the special-purpose logical processing chip. Afterwards PLC has also integrated Ethernet, technologies and so on Web Server, has provided the function rich necessary software, causes the user community to use handily.On the century 80's to the 90's intermediate stages, are PLC develops the quickest time, the yearly rate continuously maintenance is 30%~40%. In this time, the PLC data acquisition handling ability, the numeral operational capability, the man-machine connection and network traffic capacity all obtains the large scale enhancement, PLC enters the process control domain gradually, unified after the partial industry control device substitutes gradually in certain applications has been at the dominant position in the process control domain the DCS system. Because PLC has the versatility strongly, the reliability high, the easy to operate, the programming simple, the adaptation surface broad and so on the characteristics, caused it is specially in the sequential control obtained the extremely widespread application in the industrial automation control.Applies PLC in the hydroelectric power plant production equipment monitoring begins in on the century 80's, because PLC defers to the industry use environment the standard to carry on the design generally, the reliability high, antijamming ability strong, the programming simple practical, met inserts the performance good very quickly accepts by the power plant user and system integration business, obtained the good application. At present includes in Our country Hydroelectric power plant use widespread PLC: GE Fanuc Corporation's GE Fanuc 90 series, German Siemens Corporation's S5, S7 series, French Schneider Corporation's Modicon Premium, Atrium and Quantum, American Rockwell Corporation PLC5, Control Logix, Japanese OMRON Corporation's SU-5, SU-6, SU-8, Japanese MITSUBISHI Corporation's FX2 series and so on. Because each kind of PLC principle of design difference is big, the product function, the performance as well as may constitute the location system scale to have the very big difference. Generally speaking, according to the different power plant in the security performance (including reliability, maintainable and so on), aspect and so on application function, control scale, system structure actual demands carries on the choice, may find appropriate PLC. At present there is big part of power plants the automated system all uses the PLC constitution location control section, and matches through the reasonable disposition, they basically all can shoulder the corresponding responsibility in the system, completes the corresponding function.But PLC took but one kind of general automated installment, is by no means designs specially for the hydroelectric power plant automation, this has in the special request profession application in the water and electricity automation also to be able to have some not suitable place inevitably, presently lists following several points:(1) PLC by “scanning”the way work, cannot satisfy the event resolution and the system clock synchronization request. The hydroelectric power plant computer supervisory system all is a multi-computer system, in order to guarantee the event resolution should have certain event besides PLC itself to respond ability and the high accuracy clock, but also requests in the overall system between various part of main equipment clock synthesis precision also to have to guarantee in a millisecond level. But take PLC as the foundation location control device if does not take the special measure, is unable to guarantee the hydroelectric power plant safe operation to the event resolution and the system clock synchronization request.(2) general PLC origin mainly aims at the machine-finishing profession, later gradually will expand all the various trades and occupations. Although present PLC has strongly from diagnosis function, but regarding the input, the output unit, it only from diagnoses the module level. This produces this kind of emphasis regarding our country electric power “the safety first” the profession said that, has certain being short of, often needs to add seperately the special security measure.(3) general PLC all has certain surge suppression ability generally, basically may suit the majority of profession application. But says regarding the hydroelectric power plant automated system, as a result of the equipment working conditions particularity, three level of surge suppression ability which the general PLC surge suppression ability and the technology standard request also has some disparities.2.2 intelligent location controllerApplies the many another kind of location control unit in Hydroelectric power plant automated system to be supposed to be the intelligent location controller, like ABB Corporation AC450, south auspicious group's SJ-600 series, Elin Corporation's SAT1703 and so on.AC450 is being suitable which ABB Corporation produces in industry environment Advant Controller series location control unit one kind, mainly applies in other profession DCS. It has included the module which by Motorola 68040 primarily processor CPU modules and I/O, MasterBus and so on many kinds of may elect, supports centralized I/O and distributional I/O, may act according to the different application demand to use the different module to constitute the suitable location subsystem.SAT1703 is the multi-processor system which Austrian Elin Corporation produces, it is loaded with different connection processor subsystem AK1703, AME1703 and AM1703 including 3. Each sub-system by the host processor, the connection template (module), constitutions and so on connection module, can realize the data processing, the control and the correspondence function, uses SMI in the LCU interior (Serial Module Interconnector) to carry on the correspondence. SAT1703 location control unit uses OS/2 operating system, the movement control software is ToolBox.SJ-600 series is on the international telegram automation research institute the century at the end of 90's for the domestically produced intelligence distributional location control unit which moves under the bad industry environment produces, by the master control module, the intelligent I/O module, the power source module as well as connects various modules and the master controlmodule scene bus network is composed. Moved reliably in the national dozens of large and middle scale hydroelectric power plants. Below SJ-600 has the main characteristic:(1), the master control module uses conforms to IEEE1996.1's embedded module standard PC104, has the reliability high, the scene environment compatibility strong and so on the characteristics. Uses low power loss embedded CPU, may choose the CPU model from 486 to the Pentium series.(2) 32 intelligence I/O module. All modules use 32 embedded CPU, this CPU designs specially for the embedded control, on the software uses the board level real-time operating system and the unification procedure code, only is different moves the corresponding duty according to the module. Has used large-scale programmable logic chip (EPLD) and the Flash memory, simplified the system design, enhanced the reliability. The intellectualized I/O module except may complete the data acquisition and the pretreatment independently, but also has very strongly from the diagnosis function, has provided the reliable control security and the convenience breakdown localization ability.(3) has the field bus network system structure, the system uses two network architectures, first is the factory cascade control network, connects LCU and the factory level computer, constitutes the distributed computer supervisory system; Second is I/O main line network, the connection master control module and the intelligent I/O module (location or long-distance), constitutes the distributional location control subsystem. All I/O module provides two field bus network connection, these modules all may disperse the arrangement, forms the redundant reliable distributional redundant system.(4) LCU direct connection high speed network. The network has become in the computer supervisory system the important part, it involves to the power plant control strategy and the movement way. Beforehand location controller many is the use private network carries on the connection with on position machine system, but conforms to the open standard network. If AC450 uses MB300 network with on position machine system connection, but with uses TCP/IP agreement the system connection only to be able to carry on through the special-purpose module by the VIP way the data transmission which limits.(5) has provided the direct GPS synchronized clock connection, does not need to program and the establishment. GPS to when may go directly to the module level, satisfied had the special request situation to the clock, like SOE and so on.(6) provides based on IEC61131-3 standard control language, in retained trapezoidal programming language in and so on the chart, structure text, instruction list foundations, developed the use “to see namely obtained”the technical design visualization flow chart programming language. The support control flow online debugging and playbacking, suits the complex control flow extremely the production and the maintenance.(7) in view of hydroelectric power plant automation specialized application development special-purpose function module.现地控制单元在水电厂自动化中的应用1. 前言水力发电与燃煤、燃油、核能发电相比，能源是可再生的、永不枯竭的清洁能源。

精品机械工程及自动化专业毕业设计翻译

Studies in dynamic design of drilling machine using updated finite element modelsAbstractThe aim of the present work is to develop updated FE models of a drilling machine using analytical and experimental results. These updated FE models have been used to predict the effect of structural dynamic modifications on vibration characteristics of the drilling machine. Two studies have been carried out on the machine. In the first study, modal tests have been carried out on a drilling machine using instrumented impact hammer. Modal identification has been done using global method of modal identification. For analytical FE modeling of the machine, a computer program has been developed. The results obtained using FEM, have been correlated with the experimental ones using mode shape comparison and MAC values. Analytical FE model has been updated, with the help of a program, which has been developed using direct methods of model updating. In the second study, modal testing has been carried out using random noise generator and modal exciter. Global method has been used for modal identification. Analytical FE modeling has been done using I-DEAS software. Correlation of FE results with the experimental ones has been carried out using FEMtools software. Updating of the analytical FE model has also been done using the above software, based on an indirect technique viz. sensitivity based parameter estimation technique. The updated FE models, obtained from both the studies have been used for structural dynamic modifications (SDM), for the purpose of dynamic design and the results of SDM predictions are seen to be reasonably satisfactory.Article Outline1. Introduction2. Modal testing and identification3. Finite element formulation of drilling machine4. Comparison of analytical FE and experimental results (model correlation)5. Finite element model updating6. SDM studies using updated models for dynamic design7. ConclusionsReferences1. IntroductionDynamic design aims at obtaining desired dynamic characteristics in machines and structures, which may include shifting of natural frequencies, desired mode shapes and vibratory response. The ultimate objectives are to have a quieter and more comfortable environment, higher reliability and better quality of product. The conventional dynamic design is basically hit and trial method in which we try to achieve desired dynamic characteristics by making several prototypes. The disadvantage of this technique is that actual design cycle takes a lot of time and therefore it is not cost effective. However, model updating based dynamic design saves design cycle time as well as reduces the cost involved. Various tools used for updating based dynamic design are: experimental modal analysis (EMA) including modal testing and modal identification, model updating and structural dynamic modification.Ewins [1]and Maia and Silva [2]have explained the basic concepts of modal testing, which is an experimental approach to obtain mathematical model of a structure. In a modal test, the structure under test is excited either by an impact hammer or by a modal exciter, and the response of the structure is recorded at several experimental points, in the form of frequency response functions (FRFs), using a dual channel FFT analyzer. The experimental modal model gives information about the natural frequencies, corresponding mode shapes and modal damping factor and is useful for model updating. The model updating techniques helps us to bring analytical finite element models closer to real systems. In model updating an initial analytical FE model constructed for analyzing the dynamics of a structure is refined or updated using test data measured on actual structure such that the updated model describes the dynamic properties of the structure more correctly. The inaccuracies in FEM, when applied to dynamic problems are due to uncertainties in boundary conditions and structural damping etc.Friswell and Mottershead [3] have discussed the finite element model updating in structural dynamics. Baruch and Bar-Itzhack and Baruch [4] and [5] considered analytical mass matrix to be exact and developed a direct method for updating using test data. Berman and Nagy [6]developed a method of model updating, which uses measured modes and natural frequencies to improve analytical mass and stiffness matrices. Structural dynamic modification (SDM) techniques [7]and [8]are the methods by whichdynamic behaviour of the structure is improved by predicting the modified behaviour brought about by adding modifications like those of lumped masses, rigid links, dampers etc. Thus the dynamic design using updated model is expected to be helpful in order to predict accurately and quickly, the effect of possible modifications on the dynamic characteristics of the structure at computer level itself, thus saving time and cost.Sestieri [7]has discussed SDM application to machine tools and engines. Kundra [8]gave the method of structural dynamic modification via models. Modak [9] has discussed SDM predictions using updated FE model for an F-structure. He used constrained nonlinear optimization method for updating of a machine tool using stiffness parameters at the boundary [10]. The present paper deals with the FE model updating using direct as well as indirect method, and to use this updated FE model for dynamic design based on SDM predictions of a machine tool viz. a drilling machine. Two different studies are reported using different techniques for analytical and experimental analysis and for updating. Various objectives with which the present research work has been carried out are• To develop updated FE models of a complex structure like that of a drilling machine and to use these updated models to predict the effect of various modifications on modal properties of the machine.• To see whether hammer excitation yields good results for fairly complex structures like drilling machine or not, and to compare these results with those obtained from modal exciter.• To analyze the results of SDM predictions obtained using the updated models derived in the studies.2. Modal testing and identificationIn the two studies mentioned earlier, different techniques have been used, for modal testing and identification. In the first study, impact hammer is used to excite the drilling machine structure, at various points as shown in Fig. 1 and Fig. 2. Response is taken at a fixed point with the help of an accelerometer.(12K)Fig. 1. Experimental setup (Study 1).(4K)Fig. 2. Hammer excitation locations.In the present study, the drilling machine is excited at 30 locations and therefore, 30 FRFs are obtained. These FRFs are recorded in the form of inertance. The experimental FRFs, thus obtained are transferred to computer. Modal identification or modal parameter extraction consists of curve fitting a theoretical expression for an individual FRF to the actual measured data obtained. The experimental FRFs are analyzed by GRF-M method using modal analysis software ICATS [11] to obtain modal parameters of the drilling machine. In the second study, the machine tool structure has been excited at the base at point 28, referring to Fig. 2, using modal exciter and response has been measured at various points using piezoelectric accelerometers. The modal identification of the FRFs, thus measured has been carried out using global method GRF-M method in ICATS software.Table 1compares the experimental natural frequencies obtained from both the methods, which shows minor differences in the two modal frequenciesTable 1.3. Finite element formulation of drilling machineSeveral books have given the basic concepts of finite element analysis, some of them are: Zienkiewicz [12] and Bathe [13].The drilling machine structure is very complicated with different mountings and accessories. Therefore exact modeling and analysis of the actual structure is difficult and it takes more computational effort. However for analytical FE analysis, simplified model of drilling machines has been considered. In study 1, the finite element modelling has been done using a program developed in MATLAB. Beam elements have been used for the analysis. The joints and boundary conditions are considered to be rigid and influence of structural damping on modal model parameters, is ignored. The relevant data used for the drilling machine is given below:25 mm pillar type, height = 1.655 m, mass density = 7800 kg/m3, Young’s modulus= 200 Gpa, number of nodes = 30, number of elements = 29, number of nodes per element = 2, degrees of freedom per node = 3.Fig. 3shows the structure of the drilling machine with the node numbers given for study 1.(7K)Fig. 3. Drilling machine structure for FE analysis.The eigenvalues and eigenvectors have been calculated. The analytical FE model of the structure consists of 90 ×90-size mass and stiffness matrices (30 ×3, 30 nodes and 3 d.o.f. per node). But by experiment only 30 coordinates can be measured. Therefore FE model has been reduced using Guyan [14] reduction method with the help of a program developed in MATLAB.In study 2, the finite element modelling has been done using I-DEAS software. The model has been made using beam mesh. Although the FE model has been simplified but the beam elements has rotational degree of freedom, which cannot be measured experimentally. Therefore the FE model needs to be reduced. The FE model has been reduced using model reduction utility。

机械设计制造及自动化毕业设计英文翻译资料

A NOVEL INTEGRATED SYSTEM FOR RAPID PRODUCT DEVELOPMENTThis paper presents a novel integrated system of rapid product development for reducing the time and cost of product development. The system is composed of four building blocks —digital prototype, virtual prototype, physical prototype and rapid tooling manufacturing system. It can aid effectively in product design, analysis, prototype, mould, and manufacturing process development by integrating closely the various advanced manufacturing technologies which involve the 3D CAD, CAE, reverse engineering, rapid prototyping and rapid tooling. Furthermore, two actual examples are provided to illustrate the application of this integrated system. The results indicate that the system has a high potential to reduce further the cycle and cost of product development.Keywords: Rapid product development; rapid prototyping; integrated system.1. IntroductionDue to the pressure of international competition and market globalization in the 21st century, there continues to be strong driving forces in industry to compete effectively by reducing manufacturing times and costs while assuring high quality products and services. Current industries are facing the new challenges: quick response to business opportunity has been considered as one of the most important factors to ensure company competitiveness; manufacturing industry is evolving toward digitalization, network and globalization. Therefore, new products must be more quickly and cheaply developed, manufactured and introduced to the market. In order to meet the demand of rapid product development, the various new technologies such as reverse engineering (RE), 3D CAD, rapid prototyping (RP), and rapid tooling (RT) have emerged and are regarded as key enabling tools with the ability to shorten the product development and manufacturing time. For example, it has been claimed that RP can cut new product development costs by up to 70% and the time to market by 90%.1 In the form of a better design, more design possibilities, a 3D CAD model can be shown to the customer for approval and prevents misunderstandings. A virtual prototyping is employed to guide in optimizationof the product design and manufacturing process planning, which may result in the accurate determination of the process parameters, and reduce the number of costly physical prototype iterations. Rapid tooling technique offers a fast and low cost method to produce moulds, and shows a high potential for faster response to market demands. When properly integrated among 3D CAD, CAE, RE, RP and RT, these technologies will play a much more important role to reduce further the development cycle and cost of the product production. On the basis of above technologies, a novel integrated system of rapid product development is to be founded so as to meet the requirement of rapid product development.2. Architecture of the Integrated Development SystemThe development process from initial conceptual design to commercial product is an iterative process which includes: product design; analysis of performance, safety and reliability; product prototyping for experimental evaluation; and design modification. Therefore, any step of the new product development process has a direct and strong influence on time-to-market in short order. A good product development system must enable designers or design teams to consider all aspects of product design, manufacturing, selling and recycling at the early stage of the design cycle. So that design iteration and changes can be made easily and effectively. The more fluent the feedback is the higher possibility of success the system has. Design for manufacturing (DFM) and concurrent engineering (CE) necessitate that product and process design be developed simultaneously rather than sequentially.The integrated system of rapid product development is composed of four modules: digital prototype, virtual prototype, physical prototype and rapid tooling.The product development starts from the creation of a 3D CAD model using a CAD software package. At that stage, the product geometry is defined and its aesthetic and dimensional characteristics are verified. The main function of digital prototype is to perform 3D CAD modelling. The CAD model is regarded as a central component of the whole system or project information base which means that in all design, analysis and manufacturing activities the same data is utilized. The product and its components are directly designed on a 3D CAD system (e.g.Pro/Engineer, Unigraphics, CATIA, IDEAS, etc.) during the creative design. If a physical partis ready, the model can be constructed by the reverse engineering technique. RE is a methodology for constructing CAD models of physical parts by digitizing an existing part, creating a digital model and then using it to manufacture components. RE can reduce the development cycle when redesigns become necessary for improved product quality. Preexisting parts with features for improved performance can be readily incorporated into the desired part design. Therefore, it is very useful in creating the CAD model of an existing part when the engineering design is lost or has gone through many design changes. When a designer creates a new design using mock-up, it is also necessary to construct the CAD model of the mock-up for further use of the design data in analysis and manufacturing. The three primary steps in RE process are part digitization, features extraction, and CAD modelling. Part digitization is accomplished by a variety of contact or non-contact digitizers. There are various commercial systems available for part digitization. These systems range from coordinate measuring machine (CMM), laser scanners to ultrasonic digitizers. They can be classified into two broad categories: contact and non-contact. Laser triangulation scanner (LTS), magnetic resonance images (MRI), and computer tomography (CT) are commonly used as non-contact devices. Contact digitizers mainly have CMM and cross-sectional imaging measurement (CIM). Feature extraction is normally achieved by segmenting the digitized data and capturing surface features such as edges. Part modelling is fulfiled through fitting a variety of surfaces to the segmented data points.In order to reduce the iterations of design-prototype-test cycles, increase the product process and manufacturing reliability, it is necessary to guide in optimizing the product design and manufacturing process through virtual prototype (VP). VP is a process of using 3D CAD model, in lieu of a physical prototype, for testing and evaluation of specific characteristics of a product or a manufacturing process. It is often carried out by CAE and virtual manufacturing system. Computer aided engineering (CAE) analysis is an integral part of time-compression technologies. Various software tools available (i.e. ANSYS, MARC, I-DEAS, AUTOFORM, DYNAFORM, etc.) can speed up the development of new products by initiating design optimization before physical prototypes are built. The CAD models can be transferred to a CAE environment for an analysis of the product functional performance and of the manufacturing processes for producing the product’s components. It has also proven to be ofgreat value in the design optimization of part geometry, to determine its dimensions and to control warpage and shrinkage while minimizing process-induced residual stresses and deformations. Virtual manufacturing system (VM) is the natural extension of CAE. It simulates the product functionality and the processes for producing it prior to the development of physical prototypes. VM enables a designer to visualize and optimize a product process with a set of process parameters. The visualization of a virtually simulated part prior to physical fabrication helps to reduce unwanted prototype iterations. Therefore, a product virtual manufacturing system may result in accurate determination of the process parameters, and reduce the number of costly physical prototype iterations. 3D CAD model and VP allow most problems with unfitting to become obvious early in the product development process. Assemblies can be verified for interference as VP can be exercised through a range of tasks. Structure and thermal analysis can be performed on the same model employing CAE applications as well as simulating down-stream manufacturing processes. It is clear that VP increases process and product reliability. Although VP is intended to ensure that unsuitable designs are rejected or modified, in many cases, a visual and physical evaluation of the real component is needed. This often requires physical prototype to be produced. Hence, once the VP is finished, the model may often be sent directly to physical fabrication.The CAD model can be directly converted to the physical prototype using a RP technique or high-speed machining (HSM) process. The 3D CAD model is to be exported not only in the STL format which is considered the de facto standard for interfacing CAD and RP systems, but also in the NC coding which can be used by HSM. HSM has a potential for rapid producing plaster or wooden pattern for RT. RP is a new forming process which fabricates physical parts layer by layer under computer control directly from 3D CAD models in a very short time. In contrast to traditional machining methods, the majority of rapid prototyping systems tend to fabricate parts based on additive manufacturing process, rather than subtraction or removal of material. Therefore, this type of fabrication is unconstrained by the limitations attributed to conventional machining approaches. The application of RP technique as a useful tool can provide benefits throughout the process of developing new products. Specifically, there are serious benefits that RP can bring in the areas of market research, sales support, promotionalmaterial, and the ever-important product launch. Physical RP can also become a powerful communications tool to ensure that everyone involved in the development process fully understands and appreciates the product being developed. Hence, it can help to reduce substantially the inevitable risks in the route from product concept to commercial success, and help shorten time-to-market, improve quality and reduce cost. Over the last 20 years, RP machines have been widely used in industry. The RP methods commercially available include Stereolithgraphy (SLA), Selective Laser Sintering (SLS), Fused Deposition Manufacturing (FDM), Laminated Object Manufacturing (LOM), Ballistic Particle Manufacturing (BMP), and Three-Dimensional Printing (3D printing), etc.Once the design has been accepted, the realization of the production line represents a major task with a long lead time before any product can be put to the market. In particular, the preparation of complex tooling is usually in the critical path of a project and has therefore a direct and strong influence on time-to-market. In order to reduce the product development time and cost, the new technique of RT has been developed. RT is a technique that can transform the RP patterns into functional parts, especially metal parts. It offers a fast and low cost method to produce moulds and functional parts. Furthermore, the integration of both RP and RT in development strategy promotes the implementation of concurrent engineering in companies. Numerous processes have been developed for producing dies from RP system. The RT methods can generally be divided into direct and indirect tooling categories, and also soft (firm) and hard tooling subgroups. Indirect RT requires some kinds of master patterns, which can be made by conventional methods (e.g. HSM), or more commonly by an RP process such as SLA or SLS. Direct RT, as the name suggests, involves the manufacturing of a tool cavity directly on a RP system, hence eliminating the intermediate step of generating a pattern. Soft tooling can be obtained via replication from a positive pattern or master. Soft tooling is associated with low costs; used for low volume production and uses materials that have low hardness levels such as silicones, epoxies, low melting point alloys, etc. RTV silicone rubber moulds, epoxy moulds, metal spraying moulds, etc. are some of these typical soft moldings. Hard tooling is associated with higher volume of production, and the use of materials of greater hardness. Keltool process, Quickcast process, and the ExpressTool process are some of these hard toolings. Electrical discharge machining (EDM) seemsto be an interesting area in which rapid tooling finds a potential application. Some methods of making EDM electrodes based on RP technique have developed, such as abrading process, copper electroforming and net shape casting, etc. On the basis of the above techniques, a novel integrated system of rapid product development is to be proposed. Its overall architecture is shown in Fig. 1.3. Case Studies3.1. Case study 1: ImpellerA total of thirty plastic impellers, with a relatively complex geometry, were required by acustomer within fifteen working days from the receipt of a 2D CAD model. There were many factors to be considered in deciding the most appropriate route for producing the impellers. These factors mainly involved cost, lead-time, the number of parts required, the final material for the parts, and the part geometry. In order to maximize the benefits in terms of time and cost reduction for the parts, it was decided to use silicon rubber mould and the parts were eventually produced by vacuum casting process. Silicon rubber mould is an easy, relatively inexpensive and fast way to fabricate prototype or pre-production tools. It can be utilized for moulding parts in wax, polyurethane, ABS, and a few epoxy materials. The process is best suited for projects where form, fit, or functional testing can be done with a material which mimics the characteristics of the production material. The casting parts with fine details and very thin walls can be easily and rapidly produced. The whole process flow involved the 3D CAD modelling, producing master pattern (RP prototype), silicon rubber mould, and casting green parts. The time sequence for the fabrication of impellers was described as follows. Due to the complexity of the impeller, the task of generating the 3D CAD model using Pro/Engineer software package took almost 3 calendar days. The master pattern for this project was built on a SPS 600 machine in 2 calendar days. SL process was chosen because it was cost effective and the surface finish was good. The next step involved creating a roomtemperature vulcanized (RTV) silicone rubber mold which was completed within an additional 3 calendar days. Finally, the ABS materials were cast into silicon rubber mould under the vacuum casting condition, and the green parts were achieved in 4 calendar days. The required 30 components were produced successfully and completed in 12 calendar days. The primary process stages are illustrated in Fig. 2. These impellers only cost about 5 thousand RMB and took 12 working days. Consequently, in contrast to the traditional development mode, the impellers developed using the integrated system can cut cost by up to 50% and the time-to-market by 75%. When evaluated against satisfying urgent requirement with respect to time, the procedure is clearly worth pursuing, as indicated by the case study described above. Gong from a 3D CAD solid modeling to fully functional production impellers in less than 12 working days is certainly extraordinary.With proper implementation of the process by qualified personnel, working within the scope of the constraints noted, the acceptance and advancement of the integrated manufacturing methodis likely to grow.3.2. Case study 2: MannequinTen plastic mannequins were required by a client in three months from the receipt of the plaster model of the emulational body. This component was an ideal candidate for using integrated system to development, with a very complex surface and a requirement for only 10 parts. In order to produce the plastic mannequin, the various technologies including reverse engineering, 3D CAD, rapid prototyping and rapid tooling were used to complete model measuring, surfaces reconstructing, 3D CAD modelling, prototype and mould building. The whole development work was presented below. The first step of the project was to construct a CAD model of the emulational body by RE process. ATOS measuring equipment made in GOM Inc. which has a high scanning (10,000 points/sec) and can measure models in a wide range from 500mm to 10mm, was employed to capture the digitized data of the plaster mold. Figure 3(a) shows the point clouds of the body model. The subsequent process was to perform surfaces reconstructing. To speed this process, a special reverse engineering program, called CopyCAD (DelcamInc.), was used to create quickly and easily the CAD surfaces from the digitized data. After surfaces reconstructing, many errors in the original model and the joints must be modified by PowerShape software package (another software of Delcam Inc.). The surfaces model of the body is represented in Fig. 3(b). To fabricate easily, the surface model was divided into 11 individual components which included the head, body, upper arms, forearms, tights, shanks and feet using Pro/Engineer software package. Subsequently, every surface model was converted to a solid model, and many holes and slots needed to be designed for fixing joints such as shoulder, knees, etc. Then, the solid parts and joints were assembled to form the solid model of the emulational body. Figure 3(c) illustrates the completed CAD solid model. The RP prototypes of these components were built on a LPS 600 machine. The assembly RP body model is shown in Fig. 3(d). In addition, silicon rubber moulds of these components were fabricated for producing the green parts. Finally, the required 10 plastic mannequins were produced successfully and the project was completed in about 12 weeks. Figures 3(e) and (f) describe respectively the silicon rubber mould of half head and the green product. The case indicates the rapid development of large product and complex surfaces can be realized quickly following the integrated development mode.4. ConclusionIn this paper, we have presented an integrated system based on RP for rapid product developing. The system consists of four modules: digital prototype, virtual prototype, physical prototype and rapid tooling. It employs fully and integrates closely the various advanced manufacturing technologies which involve the 3D CAD, RE, CAE, RP, and RT. In this system, the procedure of development from design to end product is worked step by step: design, analysis, rapid prototype and tooling. By evaluating the whole process and its various components, and comparing them with traditional process, it has been clear that one can reap benefits in various ways. The system can effectively compress the design and manufacturing cycle time and reduce the development cost, which is an important factor in competition. Using this integrated system to develop new product shows a high potential for faster response to market and customers’ demands. As a result, it will play a more and more important role to reduce the manufacturing cycle and cost of product development in the future. AcknowledgementsThis research was supported by The National High Technology Research and Development Program (863 Program) under the project “The integrated manufacturing technology and equipments of rapid tooling for rapid product development”(No.2023AA421270), and “Tenth Five-Year” National Key T echnologies R&D Program of China under the project “Research and demonstrator of rapid manufacturing integrated system based on rapid prototyping” (No. 2023BA205B10- CMTT1001).。

自动化专业毕业设计外文翻译5

附录：中英文翻译英文Simulation-based Comparisons of Tahoe, Reno, and SACK TCPKevin Fall and Sally Floyd1 IntroductionIn this paper we illustrate some of the benefits of adding selective acknowledgment (SACK) to TCP. Current implementations of TCP use an acknowledgment number field that contains a cumulative acknowledgment, indicating the TCP receiver has received all of the data up to the indicated byte. A selective acknowledgment option allows receivers to additionally report non-sequential data they have received. When coupled with a selective retransmission policy implemented in TCP senders, This work was supported by the Director, office of Energy Re-search, Scientific Computing Staff, of the U.S. Department of Energy under considerable savings can be achieved Several transport protocols have provided for selective acknowledgment (SACK) of received data. These include NETBLT [CLZ87], XTP [SDW92], RDP [HSV84] and VMTP [Che88]. The first proposals for adding SACK to TCP [BJ88, BJZ90] were later removed from the TCP RFCs (Request For Comments) [BBJ92] pending further research. The cur-rent proposal for adding SACK to TCP is given in [MMFR96]. We use simulations to show how the SACK option define in [MMFR96] can be of substantial benefits relative to TCP without SACK.Without SACK, Reno TCP has performance problems when multiple packets are dropped from one window of data. These problems result from the need to await aretransmission timer expiration before re-initiating data flow. Situations in which this problem occurs are illustrated later in this paper (for example, see Section 6.4).Not all of Reno's performance problems are a necessary consequence of the absence of SACK. To show why, we implemented a variant of the Reno algorithms in our simulator, called New-Reno. Using a suggestion from Janey Hoe [Hoe95, Hoe96], New-Reno avoids many of the retransmit timeouts of Reno without requiring SACK. Nevertheless, New-Reno does not perform as well as TCP with SACK when a large number of packets are dropped from a window of data. The purpose of our discussion of New-Reno is to clarify the fundamental limitations of the absence of SACK. In the absence of SACK, both Reno and New-Reno senders can retransmit at most one dropped packet per round-trip time, even if senders recover from multiple drops in a window of data without waiting for a retransmit timeout. This characteristic is not shared by Tahoe TCP, which is not limited to retransmitting at most one dropped packet per round-trip time. However, it is a fundamental consequence of the absence of SACK that the sender has to choose between the following strategies to recover from lost data:1retransmitting at most one dropped packet per round-trip time, or2retransmitting packets that might have already been successfully delivered.To illustrate the advantages of TCP with SACK, we show simulations with SACK TCP, using the SACK implementation in our simulator. SACK TCP is based on a conservative extension of the Reno congestion control algorithms with the addition of selective acknowledgments and selective retransmission. With SACK, a sender has a better idea of exactly which packets have been successfully delivered as compared with comparable protocols lacking SACK. Given such information, a sender can avoid unnecessary delays and retransmissions, resulting in improved throughput. We believe the addition of SACK to TCP is one of the most important changes that should be made to TCP at this time to improve its performance.In Sections 2 through 5 we describe the congestion control and packet retransmission algorithms in Tahoe, Reno, New-Reno, and SACK TCP. Section 6 shows simulations with Tahoe, Reno, New-Reno, and SACK TCP in scenariosranging from one to four packets dropped from a window of data. Section 7 shows a trace of Reno TCP taken from actual Internet traffic, showing that the performance problems of Reno without SACK are of more than theoretical interest. Finally, Section 8 discusses possible future directions for TCP with selective acknowledgments, and Section 9 gives conclusions.2 Tahoe TCPModern TCP implementations contain a number of algorithms aimed at controlling network congestion while maintaining good user throughput. Early TCP implementations followed a go-back-n.model using cumulative positive acknowledgment and requiring a retransmit timer expiration to re-send data lost during transport. These TCPs did little to minimize network congestion.The Tahoe TCP implementation added a number of new algorithms and refinements to earlier implementations. The new algorithms include Slow-Start, Congestion Avoidance, and Fast Retransmit [Jac88]. The refinements include a modification to the round-trip time estimator used to set retransmission timeout values. All modifications have been described elsewhere [Jac88, Ste94].The Fast Retransmit algorithm is of special interest in this paper because it is modified subsequent versions of TCP. With Fast Retransmit, after receiving a small number of duplicate acknowledgments for the same TCP segment (dup ACKs), the data sender infers that a packet has been lost and retransmits the packet without waiting for a retransmission timer to expire, leading to higher channel utilization and connection throughput.3 Reno TCPThe Reno TCP implementation retained the enhancements incorporated into Tahoe, but modified the Fast Retransmit operation to include Fast Recovery [Jac90]. The new algorithm prevents the communication path (“pipe”) from going empty after Fast Retransmit, thereby avoiding the need to Slow-Start to refill it after a single packet loss. Fast Recovery operates by assuming each dup ACK received represents a single packet having left the pipe. Thus, during Fast Recovery the TCP sender is ableto make intelligent estimates of the amount of outstanding data.In Reno, the sender's usable window becomes other gateways that fail to monitor the average queue size) until the number of dup ACKs reaches tcprexmtthresh, and thereafter tracks the number of duplicate ACKs. Thus, during Fast Recovery the sender “inflate” its window by the number of dup ACKs it has received, according to the observation that each dup ACK indicates some packet has been removed from the network and is now cached at the receiver. After entering Fast Recovery and retransmitting a single packet, the sender effectively waits until half a window of dup ACKs have been received, and then sends a new packet for each additional dup ACK that is received.4 New-Reno TCPWe include New-Reno TCP in this paper to show how a simple change to TCP makes it possible to avoid some of the performance problems of Reno TCP without the addition of SACK. At the same time, we use New-Reno TCP to explore the fundamental limitations of TCP performance in the absence of SACK.The New-Reno TCP in this paper includes a small change to the Reno algorithm at the sender that eliminates Reno's wait for a retransmit timer when multiple packets are lost from a window [Hoe95, CH95]. The change concerns the sender's behavior during Fast Recovery when a partial ACK is received that acknowledges some but not all of the packets that were out-standing at the start of that Fast Recovery period. In Reno, partial ACKs take TCP out of Fast Recovery by “deflating” the usable window back to the size of the congestion window. In New-Reno, partial ACKs do not take TCP out of Fast Recovery. Instead, partial ACKs received during Fast Recovery are treated as an indication that the packet immediately following the acknowledged packet in the sequence space has been lost, and should be retransmitted. Thus, when multiple packets are lost from a single window of data, New-Reno can recover without a retransmission timeout, retransmitting one lost packet per round-trip time until all of the lost packets from that window have been retransmitted. New-Reno remains in Fast Recovery until all of the data outstanding when Fast Recovery was initiated has been acknowledged.The implementations of New-Reno and SACK TCP in our simulator also use a “maxburst” parameter. In our SACK TCP implementation, the “maxburst” parameter limits to four the number of packets that can be sent in response to a single incoming ACK, even if the sender's congestion window would allow more packets to be sent. In New-Reno, the “maxburst” parameter is set to four packets outside of Fast Recovery, and to two packets during Fast Recovery, to more closely reproduce the behavior of Reno TCP during Fast Recovery. The “maxburst” parameter is really only needed for the first window of packets that are sent after leaving Fast Recovery. If the sender had been prevented by the receiver's advertised window from sending packets during Fast Recovery, then, without “maxburst” ,it is possible for the sender to send a large burst of packets upon exiting Fast Recovery. This applies to Reno and New-Reno TCP, and to a lesser extent, to SACK TCP. In Tahoe TCP the Slow-Start algorithm prevents bursts after recovering from a packet loss. The bursts of packets upon exiting Fast Recovery with New-Reno TCP are illustrated in Section 6 in the simulations with three and four packet drops. Bursts of packets upon exiting Fast Recovery with Reno TCP are illustrated in [Flo95].5 SACK TCPThe SACK option follows the format in [MMFR96]. From [MMFR96], the SACK option field contains a number of SACK blocks, where each SACK block reports a non-contiguous set of data that has been received and queued. The first block in a SACK option is required to report the data receiver's most recently received segment, and the additional SACK blocks repeat the most recently reported SACK blocks [MMFR96]. In these simulations each SACK option is assumed to have room for three SACK blocks. When the SACK option is used with the Timestamp option specified for TCP Extensions for High Performance [BBJ92], then the SACK option has room for only three SACK blocks [MMFR96]. If the SACK option were to be used with both the Timestamp option and with T/TCP (TCP Extensions for Transactions) [Bra94], the TCP option space would have room for only two SACK blocks.The 1990 “Sack” TCP implementation on our previous simulator is from StevenMcCanne and Sally Floyd, and does not conform to the formats in [MMFR96]. The new “Sack1”implementation contains major contributions from Kevin Fall, Jamshid Mahdavi, and Matt Mathis.The congestion control algorithms implemented in our SACK TCP are a conservative extension of Reno's congestion control, in that they use the same algorithms for increasing and decreasing the congestion window,The SACK TCP implementation in this paper, called “Sack1”in our simulator, is also discussed in [Flo96b, Flo96a].and make minimal changes to the other congestion con-trol algorithms. Adding SACK to TCP does not change the basic underlying congestion control algorithms. The SACK TCP implementation preserves the properties of Tahoe and Reno TCP of being robust in the presence of out-of-order packets, and uses retransmit timeouts as the recovery method of last resort. The main difference between the SACK TCP implementation and the Reno TCP implementation is in the behavior when multiple packets are dropped from one window of data.中文翻译：1介绍在这篇论文中，我们将介绍使用选择重发（sack）选项的TCP协议的益处，拥塞控制，算法一般分为两类：基于窗口的和基于位率的拥塞控制算法，基于窗口的控制算法是通过源端限制数据报的传送，并且不应答。

自动化专业毕业论文外文文献翻译

目录Part 1 PID type fuzzy controller and parameters adaptivemethod ........ 1 Part 2 Application of self adaptation fuzzy-PIDcontrol for main steamtemperature control system in power station错误～未定义书签。

7Part 3 Neuro-fuzzy generalized predictive control of boiler steam temperature ........................................................ .......... (13)Part 4 为Part3译文:锅炉蒸汽温度模糊神经网络的广义预测控制21Part 1 PID type fuzzy controller and Parametersadaptive methodWu zhi QIAO, Masaharu MizumotoAbstract: The authors of this paper try to analyze the dynamic behavior of the product-sum crisp type fuzzy controller, revealing that this type of fuzzy controller behaves approximately like a PD controller that may yield steady-state error for the control system. By relating to the conventional PID control theory, we propose a new fuzzy controller structure, namely PID type fuzzy controller which retains the characteristics similar to the conventional PID controller. In order to improve further the performance of the fuzzy controller, we work out a method to tune the parameters of the PID type fuzzy controller on line, producing a parameter adaptive fuzzy controller. Simulation experiments are made to demonstrate the fine performance of these novel fuzzy controller structures.Keywords: Fuzzy controller; PID control; Adaptive control1. IntroductionAmong various inference methods used in the fuzzy controller foundin literatures , the most widely used ones in practice are the Mamdani method proposed by Mamdani and his associates who adopted the Min-max compositional rule of inference based on an interpretation of a control rule as a conjunction of the antecedent and consequent, and the product-sum method proposed by Mizumoto who suggested to introduce the product and arithmetic mean aggregation operators to replace the logical AND (minimum) and OR (maximum) calculations in the Min-max compositional rule of inference.In the algorithm of a fuzzy controller, the fuzzy function calculation is also a complicated and time consuming task. Tagagi and Sugeno proposed a crisp type model in which the consequent parts of the fuzzy control rules are crisp functional representation or crisp real numbers in the simplified case instead of fuzzy sets . With this model of crisp real number output, the fuzzy set of the inference consequence will1be a discrete fuzzy set with a finite number of points, this can greatly simplify the fuzzy function algorithm.Both the Min-max method and the product-sum method are often applied with the crisp output model in a mixed manner. Especially the mixed product-sum crisp model has a fine performance and the simplestalgorithm that is very easy to be implemented in hardware system and converted into a fuzzy neural network model. In this paper, we will take account of the product-sum crisp type fuzzy controller. 2. PID typefuzzy controller structureAs illustrated in previous sections, the PD function approximately behaves like a parameter time-varying PD controller. Since the mathematical models of most industrial process systems are of type, obviously there would exist an steady-state error if they are controlled by this kind of fuzzy controller. This characteristic has been stated in the brief review of the PID controller in the previous section.If we want to eliminate the steady-state error of the control system, we can imagine to substitute the input (the change rate of error or the derivative of error) of the fuzzy controller with the integration of error. This will result the fuzzy controller behaving like a parameter time-varying PI controller, thus the steady-state error is expelled by the integration action. However, a PI type fuzzy controller will have a slow rise time if the P parameters are chosen small, and have a large overshoot if the P or I parameters are chosen large. So there may be the time when one wants to introduce not only the integration control butthe derivative control to the fuzzy control system, because thederivative control can reduce the overshoot of the system's response so as to improve the control performance. Of course this can be realized by designing a fuzzy controller with three inputs, error, the change rateof error and the integration of error. However, these methods will behard to implement in practice because of the difficulty in constructing fuzzy control rules. Usually fuzzy control rules are constructed by summarizing the manual control experience of an operator who has been controlling the industrial process skillfully and successfully. The operator intuitively regulates the executor to control the process by watching the2error and the change rate of the error between the system's output and the set-point value. It is not the practice for the operator to observe the integration of error. Moreover, adding one input variable will greatly increase the number of control rules, the constructing of fuzzy control rules are even more difficult task and it needs more computation efforts. Hence we may want to design a fuzzy controller that possesses the fine characteristics of the PID controller by using only the error and the change rate of error as its inputs.One way is to have an integrator serially connected to the output of the fuzzy controller as shown in Fig. 1. In Fig. 1,andare scalingfactors for e and ~ KK12respectively, and fl is the integral constant. In the proceeding text, for convenience, we did not consider the scaling factors. Here in Fig. 2, when we look at the neighborhood of NODE point in the e - ~ plane, it follows from (1) that the control input to the plant can be approximated by(1)Hence the fuzzy controller becomes a parameter time-varying PI controller, its equivalent proportional control and integral control components are BK2D and ilK1 P respectively. We call this fuzzy controller as the PI type fuzzy controller (PI fc). We can hope that ina PI type fuzzy control system, the steady-state error becomes zero.3To verify the property of the PI type fuzzy controller, we carry out some simulation experiments. Before presenting the simulation, we give a description of the simulation model. In the fuzzy control system shownin Fig. 3, the plant model is a second-order and type system with the following transfer function:K (2) G(s),(Ts，1)(Ts，1)12Where K = 16, = 1, and= 0.5. In our simulation experiments, we use the TT12discrete simulation method, the results would be slightly different from that of a continuous system, the sampling time of the system is set to be 0.1 s. For the fuzzy controller, the fuzzy subsets of e and d are defined as shown in Fig. 4. Their coresThe fuzzy control rules are represented as Table 1. Fig. 5 demonstrates the simulation result of step response of the fuzzy control system with a Pl fc. We can see that the steady-state error of thecontrol system becomes zero, but when the integration factor fl is small, the system's response is slow, and when it is too large, there is a high overshoot and serious oscillation. Therefore, we may want to introduce the derivative control law into the fuzzy controller to overcome the overshoot and instability. We propose a controller structure that simply connects the PD type and the PI type fuzzy controller together in parallel. We have the equivalent structure of that by connecting a PI device with the basic fuzzy controller serially as shown in Fig.6. Where ~ is the weight on PD type fuzzy controller and fi is that on PI type fuzzy controller, the larger a/fi means more emphasis on the derivative control and less emphasis on the integration control, and vice versa. It follows from (7) that the output of the fuzzy controller is(3)43. The parameter adaptive methodThus the fuzzy controller behaves like a time-varying PID controller, its equivalent proportional control, integral control and derivative control components are respectively. We call this new controllerstructure a PID type fuzzy controller (PID fc). Figs. 7 and 8 are the simulation results of the system's step response of such control system. The influence of ~ and fl to the system performance is illustrated. When ~ > 0 and/3 = 0, meaning that the fuzzy controller behaves like PD fc, there exist a steady-state error. When ~ = 0 and fl > 0, meaning thatthe fuzzy controller behaves like a PI fc, the steady-state error of the system is eliminated but there is a large overshoot and serious oscillation.When ~ > 0 and 13 > 0 the fuzzy controller becomes a PID fc, the overshoot is substantially reduced. It is possible to get acomparatively good performance by carefully choosing the value of ,and. ,4. Conclusions5We have studied the input-output behavior of the product-sum crisp type fuzzy controller, revealing that this type of fuzzy controller behaves approximately like a parameter time-varying PD controller. Therefore, the analysis and designing of a fuzzy control system can take advantage of the conventional PID control theory. According to the coventional PID control theory, we have been able to propose some improvement methods for the crisp type fuzzy controller.It has been illustrated that the PD type fuzzy controller yields a steady-state error for the type system, the PI type fuzzy controller can eliminate the steady-state error. We proposed a controller structure,that combines the features of both PD type and PI type fuzzy controller, obtaining a PID type fuzzy controller which allows the control system to have a fast rise and a small overshoot as well as a short settling time.To improve further the performance of the proposed PID type fuzzy controller, the authors designed a parameter adaptive fuzzy controller. The PID type fuzzy controller can be decomposed into the equivalent proportional control, integral control and the derivative control components. The proposed parameter adaptive fuzzy controller decreases the equivalent integral control component of the fuzzy controllergradually with the system response process time, so as to increase the damping of the system when the system is about to settle down, meanwhile keeps the proportional control component unchanged so as to guarantee quick reaction against the system's error. With the parameter adaptive fuzzy controller, the oscillation of the system is strongly restrained and the settling time is shortened considerably.We have presented the simulation results to demonstrate the fine performance of the proposed PID type fuzzy controller and the parameter adaptive fuzzy controller structure.6Part 2 Application of self adaptation fuzzy-PID control for main steam temperature control system inpower stationZHI-BIN LIAbstract: In light of the large delay, strong inertia, anduncertainty characteristics of main steam temperature process, a self adaptation fuzzy-PID serial control system is presented, which not only contains the anti-disturbance performance of serial control, but also combines the good dynamic performance of fuzzy control. The simulation results show that this control system has more quickly response, better precision and stronger anti-disturbance ability(Keywords:Main steam temperature;Self adaptation;Fuzzy control;Serial control1. IntroductionThe boiler superheaters of modem thermal power station run under the condition of high temperature and high pressure, and the superheater’s temperature is highest inthe steam channels(so it has important effect to the running of the whole thermal power station(If the temperature is too high, it will be probably burnt out. If the temperature is too low ,the efficiency will be reduced So the main steam temperature mast be strictly controlled near the given value(Fig l shows the boiler main steamtemperature system structure.Fig.1 boiler main steam temperature systemIt can be concluded from Fig l that a good main steam temperature control7system not only has adequately quickly response to flue disturbance and loadfluctuation, but also has strong control ability to desuperheating water disturbance.The general control scheme is serial PID control or double loop control systemwith derivative. But when the work condition and externaldisturbance changelarge, the performance will become instable. This paper presents aself adaptationfuzzy-PID serial control system. which not only contains the anti-disturbanceperformance of serial control, but also combines the good dynamic character andquickly response of fuzzy control(1. Design of Control SystemThe general regulation adopts serial PID control system with loadfeed forward(which assures that the main steam temperature is near the given value 540?in most condition(If parameter of PID control changeless and the workcondition and external disturbance change large, the performancewill become in stable(The fuzzy control is fit for controlling non-linear and uncertain process. The general fuzzy controller takes error E and error change ratio EC as input variables(actually it is a non-linear PD controller, so it has the good dynamic performance(But the steadyerror is still in existence. In linear system theory, integral can eliminate the steady error. So if fuzzy control is combined with PI control, not only contains the anti-disturbance performance of serial control, but also has the good dynamic performance and quickly response.In order to improve fuzzy control self adaptation ability, Prof(Long Sheng-Zhaoand Wang Pei-zhuang take the located in bringing forward a new idea which can modify the control regulation online(This regulation is: U,,E，(1,,)EC,,,[0,1]This control regulation depends on only one parameter.Onceisfixed(the ,,weight of E and EC will be fixed and the self adaptation abilitywill be very small(Itwas improved by Prof. Li Dong-hui and the new regulation is as follow;8,,，(1,),,0EECE00,,，(1,),,,1EECE11,{U,,，(1,),,,2EECE 22,,E，(1,)EC,E,,333,,,,,,,,[0,1]0123Because it is very difficult to find a self of optimum parameter, a new method ispresented by Prof(Zhou Xian-Lan, the regulation is as follow:2,,1,exp(,ke),(k,0)But this algorithm still can not eliminate the steady error(This paper combinesthis algorithm with PI control，the performance is improved(2. Simulation of Control System3.1 Dynamic character of controlled objectPapers should be limited to 6 pages Papers longer than 6 pages will be subject toextra fees based on their length(Fig .2 main steam temperature control system structureFig 2 shows the main steam temperature control system structure，W(s),W(s)W(s),W(s)are main controller and auxiliary controller,are characters ,1,2o1o2W(s),W(s)of the leading and inertia sections,are measure unit. H1H23.2 Simulation of the general serial PID control system9The simulation of the general serial PID control system is operated by MATLAB, the simulation modal is as Fig.3.Setp1 and Setp2 are the given value disturbance and superheating water disturb & rice .PIDController1 and PID Controller2 are main controller and auxiliary controller(The parameter value which comes from references is as follow:W(s),k,25,2p21W(s),k，k，ks 1p1I1D1,sk,3.33,k,0.074,k,37.667p1I1D1Fig.3. the general PID control system simulation modal 3.3Simulation of self adaptation fuzzy-PID control system Spacing W(s),k,25The simulation modal is as Fig 4.Auxiliary controlleris:.Main ,2p2controller is Fuzzy-PI structure, and the PI controller is:1W(s),k，k,1p1I1sk,3.33,k,0.074p1I1Fuzzy controller is realized by S-function, and the code is as fig.5.Fig.4. the fuzzy PID control system simulation modal10Fig 5 the S-function code of fuzzy control3.4 Comparison of the simulationGiven the same given value disturbance and the superheating water disturbance，we compare the response of fuzzy-PID control system with PID serial control system. The simulation results are as fig.6-7.From Fig6-7,we can conclude that the self adaptation fuzzy-PID control system has the more quickly response, smaller excess and stronger anti-disturbance(4. Conclusion(1)Because it combines the advantage of PID controller and fuzzy controller, the11self adaptation fuzzy-PID control system has better performance than the general PID serial control system.(2)The parameter can self adjust according to the error E value. so this kind of controller can harmonize quickly response with system stability(12Part 3 Neuro-fuzzy generalized predictive controlof boiler steam temperatureXiangjie LIU, Jizhen LIU, Ping GUANAbstract: Power plants are nonlinear and uncertain complex systems. Reliable control of superheated steam temperature is necessary to ensure high efficiency and high load-following capability in the operation of modern power plant. A nonlinear generalized predictive controller based on neuro-fuzzy network (NFGPC) is proposed in this paper. The proposed nonlinear controller is applied to control the superheated steam temperature of a 200MW power plant. From the experiments on the plant and the simulation of the plant, much better performance than the traditional controller is obtained.Keywords: Neuro-fuzzy networks; Generalized predictive control; Superheatedsteam temperature1. IntroductionContinuous process in power plant and power station are complex systems characterized by nonlinearity, uncertainty and load disturbance. The superheater is an important part of the steam generation process in the boiler-turbine system, where steam is superheated before enteringthe turbine that drives the generator. Controlling superheated steam temperature is not only technically challenging, but also economically important.From Fig.1,the steam generated from the boiler drum passes throughthe low-temperature superheater before it enters the radiant-type platen superheater. Water is sprayed onto the steam to control the superheated steam temperature in both the low and high temperature superheaters. Proper control of the superheated steam temperature is extremely important to ensure the overall efficiency and safety of the power plant. It is undesirable that the steam temperature is too high, as it can damage the superheater and the high pressure turbine, or too low, as it will lower the efficiency of the power plant. It is also important to reduce the temperature13fluctuations inside the superheater, as it helps to minimize mechanical stress that causes micro-cracks in the unit, in order to prolong the life of the unit and to reduce maintenance costs. As the GPC is derived by minimizing these fluctuations, it is amongst thecontrollers that are most suitable for achieving this goal.The multivariable multi-step adaptive regulator has been applied to control the superheated steam temperature in a 150 t/h boiler, and generalized predictive control was proposed to control the steam temperature. A nonlinear long-range predictive controller based onneural networks is developed into control the main steam temperature and pressure, and the reheated steam temperature at several operating levels. The control of the main steam pressure and temperature based on a nonlinear model that consists of nonlinear static constants and linear dynamics is presented in that.Fig.1 The boiler and superheater steam generation processFuzzy logic is capable of incorporating human experiences via the fuzzy rules. Nevertheless, the design of fuzzy logic controllers is somehow time consuming, as the fuzzy rules are often obtained by trials and errors. In contrast, neural networks not only have the ability to approximate non-linear functions with arbitrary accuracy, they can also be trained from experimental data. The neuro-fuzzy networks developed recently have the advantages of model transparency of fuzzy logic and learning capability of neural networks. The NFN is have been used to develop self-tuning control, and is therefore a useful tool fordeveloping nonlinear predictive control. Since NFN is can be considered as a network that consists of several local re-gions, each of which contains a local linear model, nonlinear predictive control based on14NFN can be devised with the network incorporating all the local generalized predictive controllers (GPC) designed using the respective local linear models. Following this approach, the nonlinear generalized predictive controllers based on the NFN, or simply, the neuro-fuzzy generalized predictive controllers (NFG-PCs)are derived here. The proposed controller is then applied to control the superheated steam temperature of the 200MW power unit. Experimental data obtained from the plant are used to train the NFN model, and from which local GPC that form part of the NFGPC is then designed. The proposed controller is tested first on the simulation of the process, before applying it to control the power plant.2. Neuro-fuzzy network modellingConsider the following general single-input single-output nonlinear dynamic system:''y(t),f[y(t,1),...,y(t,n),u(t,d),...,u(t,d,n，1), yu'e(t,1),...,e(t,n)]，e(t)/, (1) ewhere f[.]is a smooth nonlinear function such that a Taylor series expansion exists,'''n,n,ne(t)is a zero mean whi te noise andΔis the differencing operator,and d are yuerespectively the known orders and time delay of the system. Let the local linear model of the nonlinear system (1) at the operating pointbe given by the following o(t)Controlled Auto-Regressive Integrated Moving Average (CARIMA) model: ,1,d,1,1A(z)y(t),zB(z),u(t)，C(z)e(t) (2),1,1,1,1,1A(z),,A(z),B(z)andC(z)Whereare polynomials in, the backward shift zoperator. Note that the coefficients of these polynomials are a function of the operating pointo(t).The nonlinear system (1) is partitioned into several operating regions, such that each region can be approximated by a local linear model. Since NFN is a class of associative memory networks with knowledge stored locally, they can be applied to model this class of nonlinear systems. A schematic diagram of the NFN is shown in Fig.2.B-spline functions are used as the membership functions in the15NFN for the following reasons. First, B-spline functions can be readily specified by the order of the basis function and the number of inner knots. Second, they are defined on a bounded support, and the output of the basis function is always positive,jji.e.,and.Third, the basis functionsform ,(x),0,x,[,,,],(x),0,x,[,,,]kj,kjkj,kja partition of unity, i.e.,j (3) ,(x),1,x,[xx].,kmammin,jAnd fourth, the output of the basis functions can be obtained by a recurrence equation.Fig. 2 neuro-fuzzy networkThe membership functions of the fuzzy variables derived from the fuzzy rules can be obtained by the tensor product of the univariate basis functions. As an example, consider the NFN shown in Fig.2, which consists of the following fuzzy rules:xx IF operating condition i (is positive small, ... , andis negative large), n1THEN the output is given by the local CARIMA model i:ˆˆˆy(t),ay(t,1)，...，ay(t,n)，b,u(t,d)，... ii1iiniai0ia，b,u(t,d,n)，e(t)，...，ce(t,n) (4) inibiinicbc,,d,,111ˆA(z)y(t),z,B(z)u(t)，C(z)e(t)or (5) iiiiii,1,1,1A(z),B(z)andC(z)Whereare polynomials in the backward shift iii ,1u(t)e(t)operatorz, and d is the dead time of the plant,is the control, and is a ii2zero mean independent random variable with a variance of . The multivariate basis ,a(x)functionis obtained by the tensor products of the univariate basis functions, ik16nia,,A(x),i,1,2,...,p (6) ,ikk,1kwhere n is the dimension of the input vector x, and p, the total number of weightsin the NFN, is given by,np,(R，k) (7) ,ii,1kkRWhere and are the order of the basis function and the number of inner iiknots respectively. The properties of the univariate B-spline basis functions described previously also apply to the multivariate basis function, which is defined on the hyper-rectangles. The output of the NFN is,pˆya,iip,1iˆˆy,,ya (8) ,iip,1ia,i,1i3. Neuro-fuzzy modelling and predictive control of superheatedsteam temperature,Letbe the superheated steam temperature, and, the flow of spray water to the ,,high temperature superheater. The response ofcan be approximated by a second ,order model:K,p,,sG(s),,e (9) ,()(，1)(，1)sTsTs12,The linear models, however, only a local model for the selected operating point. Since load is the unique antecedent variable, it is used to select the division between the local regions in the NFN. Based on this approach, the load is divided into five regions as shown in Fig.3,using also the experience of the operators, who regard a load of 200MW as high,180MW as medium high,160MW as medium,140MW as medium low and 120MW as low. For a sampling interval of 30s, the estimated linear ,1A(z)local models used in the NFN are shown in Table 1.17Fig. 3 Membership function for local modelsTable 1 Local CARIMA models in neuro-fuzzy modelCascade control scheme is widely used to control the superheated steam temperature. Feed forward control, with the steam flow and the gas temperature as inputs, can be applied to provide a faster response to large variations in these two variables. In practice, the feed forward paths are activated only when there are significant changes in these variables. The control scheme also prevents the faster dynamics of the plant, i.e., the spray water valve and the water/steam mixing, from affecting the slower dynamics of the plant, i.e., the high temperature superheater. With the global nonlinear NFN model in Table 1, the proposed NFGPC scheme is shown in Fig.4.18Fig. 4 NFGPC control of superheated steam temperature with feed-for-ward control.As a further illustration, the power plant is simulated using the NFN model given in Table 1,and is controlled respectively by the NFGPC, the conventional linear GPC controller, and the cascaded PI controller while the load changes from 160MW to 200MW.The conventional linear GPC controller is the local controller designed for the“medium”operating region. The results are shown in Fig.5,showing that, as expected, the best performance is obtained from the NFGPC as it is designed based on amore accurate process model. This is followed by the conventional linear GPC controller. The performance of the conventional cascade PIcontroller is the worst, indicating that it is unable to control satisfactory the superheated steam temperature under large load changes. This may be the reason for controlling the power plant manually when there are large load changes.Fig.5 comparison of the NFGPC, conventional linear GPC, and cascade PI controller. 4. ConclusionsThe modeling and control of a 200 MW power plant using the neuro-fuzzy approach is presented in this paper. The NFN consists of fivelocal CARIMA models.19The out-put of the network is the interpolation of the local models using memberships given by the B-spline basis functions. The proposed NFGPC is similarly constructed, which is designed from the CARIMA models in the NFN. The NFGPC is most suitable for processes with smooth nonlinearity, such that its full operating range can be partitioned into several local linear operating regions. The proposed NFGPC therefore provides a useful alternative for controlling this class of nonlinearpower plants, which are formerly difficult to be controlled using traditional methods.20Part 4 为Part3译文:锅炉蒸汽温度模糊神经网络的广义预测控制Xiangjie LIU, Jizhen LIU, Ping GUAN摘要:发电厂是非线性和不确定性的复杂系统。

自动化专业毕业设计(论文)外文翻译-----电子动力转向系统

自动化专业毕业设计（论文）外文翻译Electronic power steering systemWhat it isElectrically powered steering uses an electric motor to drive either the power steering HYPERLINK "/infobank/epc.htm" \t "_top" hydraulic pump or the steering linkage directly. The power steering function is therefore independent of engine speed, resulting in significant energy savings.How it works :Conventional power HYPERLINK "/infobank/epc.htm" \t "_top" steering systems use an engine accessory belt to drive the pump, providing pressurized fluid that operates a piston in the power steering gear or actuator to assist the driver.In electro-hydraulic steering, one electrically powered steering concept uses a high efficiencypump driven by an HYPERLINK "/infobank/epc.htm" \t "_top" electric motor. Pump speed is regulated by an electric controller to vary pump pressure and flow, providing steering efforts tailored for different driving situations. The pump can be run at low speed or shut off to provide energy savings during straight ahead driving (which is most of the time in most world markets).Direct electric steering uses an electric motor attached to the HYPERLINK "/infobank/epc.htm" \t "_top" steering rack via a gear mechanism (no pump or fluid). A variety of motor types and gear drives is possible. A microprocessor controls steering dynamics and driver effort. Inputs include vehicle speed and steering, wheel torque, angular position and turning rate.Working In Detail:A "steering sensor" is located on the input shaft where it enters the gearbox housing. The steering sensor is actually two sensors in one: a "torque sensor" that converts steering torque input and its direction into voltage signals, and a "rotation sensor" that converts the rotation speed and direction into voltage signals. An "interface" circuit that shares the same housing converts the signals from the torque sensor and rotation sensor into signals the control electronics can process. Inputs from the steering sensor are digested by a microprocessor control unit that also monitors input from the vehicle's HYPERLINK "/infobank/epc.htm" \t "_top" speed sensor. The sensor inputs are then compared to determine how much power assist is required according to a preprogrammed "force map" in the control unit's memory. The control unit then sends out the appropriate command to the " HYPERLINK "/infobank/epc.htm" \t "_top" power unit" which then supplies the electric motor with current. The motor pushes the rack to the right or left depending on which way the voltage flows (reversing the current reverses the direction the motor spins). Increasing the current to the motor increases the amount of power assist.The system has three operating modes: a "normal" control mode in which left or right power assist is provided in response to input from the steering torque and rotationsensor's inputs; a "return" control mode which is used to assist steering return after completing a turn; and a "damper" control mode that changes with vehicle speed to improve road feel and dampen kickback.If the steering wheel is turned and held in the full-lock position and steering assist reaches a maximum, the control unit reduces current to the electric motor to prevent an overload situation that might damage the motor. The control unit is also designed to protect the motor against voltage surges from a faulty HYPERLINK "/infobank/epc.htm" \t "_top" alternator or charging problem. The electronic steering control unit is capable of self-diagnosing faults by monitoring the system's inputs and outputs, and the driving current of the electric motor. If a problem occurs, the control unit turns the system off by actuating a fail-safe relay in the power unit. This eliminates all power assist, causing the system to revert back to manual steering. A dash EPS warning light is also illuminated to alert the driver. To diagnose the problem, a technician jumps the terminals on the service check connector and reads out the HYPERLINK "/infobank/epc.htm" \t "_top" trouble codes. INCLUDEPICTURE "/infobank/images/eps-18-4.gif" \* MERGEFORMATINETHYPERLINK "/infobank/images/c01e.gif" click here to see a bigger HYPERLINK "/infobank/images/c01e.gif"INCLUDEPICTURE "/infobank/images/c01e.gif" \*MERGEFORMATINETElectric power steering systems promise weight reduction, fuel savings and package flexibility, at no cost penalty.Europe's high fuel prices and smaller vehicles make a fertile testbed for electric steering, a technology that promises automakers weight savings and fuel economy gains. And in a short time, electric steering will make it to the U.S., too. "It's just just a matter of time," says AlyBadawy, director of research and development for Delphi Saginaw Steering Systems in Saginaw, Mich. "The issue was cost and that's behind us now. By 2002 here in the U.S. the cost of electric power steering will absolutely be a wash over hydraulic." Today, electric and hybrid-powered vehicles (EV), including Toyota's Prius and GM's EV-1, are the perfect domain for electric steering. But by 2010, a TRW Inc. internal study estimates that one out of every three cars produced in the world will be equipped with some form of electrically-assisted steering. The Cleveland-based supplier claims its new steering systems could improve fuel economy by up to 2 mpg, while enhancing handling. There are true bottom-line benefits as well for automakers by reducing overall costs and decreasing assembly time, since there's no need for pumps, hoses and fluids. Another claimed advantage is shortened development time. For instance, a Delphi group developed E-TUNE, a ride-and-handling software package that can be run off a laptop computer. "They can take that computer and plug it in, attach it to the controller and change all the handling parameters -- effort level, returnability, damping -- on the fly," Badawy says. "It used to take months." Delphi has one OEM customer that should start low-volume production in '99. HYPERLINK "/adlog/c/r=12640&s=790604&o=13886:14023:13888:15399:&h=c n&p=&b=14&l=&site=23&pt=&nd=&pid=&cid=&pp=100&e=&rqid=01c17-ad-e8480771F615DF093&orh=LINE&oepartner=&epartner=&ppartner=&pdom=&cpnmod ule=&count=&ra=10.15.56.33&t=2008.04.19.09.09.02/http://cm/ck/9 998-57911-18316-1?mpt=2008.04.19.09.09.02" \t "_blank" Electric steering units are normally placed in one of three positions: column-drive, pinion-drive and rack-drive. Which system will become the norm is still unclear. Short term, OEMs will choose the steering system that is easiest to integrate into an existing platform. Obviously, greater potential comes from designing the system into an all-new platform. "We have all three designs under consideration," says Dr. Herman Strecker, group vice president of steering systems division at ZF in SchwaebischGmuend, Germany. "It's up to the market and OEMs which version finally will be used and manufactured." "The large manufacturers have all grabbed hold of what they consider a core technology," explains James Handy sides, TRW vice president, electrically assisted steering in Sterling Heights, Mich. His company offers a portfolio of electric steering systems (hybrid electric, rack-, pinion-, and column-drive). TRW originally concentrated on what it still believes is the purest engineering solution for electric steering--the rack-drive system. The system is sometimes refer to as direct drive or ball/nut drive. Still, this winter TRW hedged its bet, forming a joint venture with LucasVarity. The British supplier received $50 million in exchange for its electric column-drive steering technology and as sets. Initial production of the column and pinion drive electric steering systems is expected to begin in Birmingham, England, in 2000."What we lack is the credibility in the steering market," says Brendan Conner, managing director, TRW/LucasVarity Electric Steering Ltd. "The combination with TRW provides us with a good opportunity for us to bridge that gap." LucasVarity currently has experimental systems on 11 different vehicle types, mostly European. TRW is currently supplying its EAS systems for Ford and Chrysler EVs in North America and for GM's new Opel Astra.In 1995, according to Delphi, traditional hydraulic power steering systems were on 7596 of all vehicles sold globally. That 37-million vehicle pool consumes about 10 million gallons in hydraulic fluid that could be superfluous, if electric steering really takes off. The present invention relates to an electrically powered drive mechamsm for providing powered assistance to a vehicle steering mechanism. According to one aspect of the present invention, there is provided an electrically powered driven mechanism for providing powered assistance to a vehicle steering mechanism having a manually rotatable member for operating the steering mechanism, the drive mechanism including a torque sensor operable to sense torque being manually applied to the rotatable member, an electrically powered drive motor drivingly connected to the rotatable member and a controller which is arranged to control the speed and direction of rotation of the drive motor in response to signals received from the torque sensor, the torque sensor including a sensor shaft adapted for connection to the rotatable member to form an extension thereof so that torque is transmitted through said sensor shaft when the rotatable member is manually rotated and a strain gauge mounted on the sensor shaft for producing a signal indicative of the amount of torque being transmitted through said shaft. Preferably the sensor shaft is non-rotatably mounted at one axial end in a first coupling member and is non-rotatably mounted at its opposite axial end in a second coupling member, the first and second coupling members being inter-engaged to permit limited rotation there between so that torque under a predetermined limit is transmitted by the sensor shaft onlyand so that torque above said predetermined limit is transmitted through the first and second coupling members. The first and second coupling members are preferably arranged to act as a bridge for drivingly connecting first and second portions of the rotating member to one another. Preferably the sensor shaft is of generally rectangular cross-section throughout the majority of its length. Preferably the strain gauge includes one or more SAW resonators secured to the sensor shaft. Preferably the motor is drivingly connected to the rotatable member via a clutch .Preferably the motor includes a gear box and is concentrically arranged relative to the rotatable member. Various aspects of the present invention will hereafter be described, with reference to the accompanying drawings, in which :Figure 1 is a diagrammatic view of a vehicle steering mechanism including an electrically powered drive mechanism according to the present invention, Figure 2 is a flow diagram illustrating interaction between various components of the drive mechanism shown in Figure 1 ,Figure 3 is an axial section through the drive mechanism shown in Figure 1, Figure 4 is a sectional view taken along lines IV-IV in Figure 3,Figure 5 is a more detailed exploded view of the input drives coupling shown in Figure 3, and Figure 6 is a more detailed exploded view of the clutch showing in Figure 3. Referring initially to Figure 1 , there is shown a vehicle steering mechanism 10 drivingly connected to a pair of steerable road wheels The steering mechanism 10 shown includes a rack and pinion assembly 14 connected to the road wheels 12 via joints 15. The pinion(not shown) of assembly 14 is rotatably driven by a manually rotatable member in the form of a steering column 18 which is manually rotated by a steering wheel 19.The steering column 18 includes an electric powered drive mechanism 30 which includes an electric drive motor (not shown in Figure 1) for driving the pinion in response to torque loadings in the steering column 18 in order to provide power assistance for the operative when rotating the steering wheel 19.As schematically illustrated in Figure 2, the electric powered drive mechanism includes a torque sensor20 which measures the torque applied by the steering column 18 when driving the pinion and supplies a signal to a controller 40. The controller 40 is connected to a drive motor 50 and controls the electric current supplied to the motor 50 to control the amount of torque generated by the motor 50 and the direction of its rotation. The motor 50 is drivingly connected to the steering column 18 preferably via a gear box 60, preferably an epicyclic gear box, and a clutch 70. The clutch 70 is preferably permanently engaged during normal operation and is operative under certain conditions to isolate drive from the motor 50 to enable the pinion to be driven manually through the drive mechanism 30. This is a safety feature to enable the mechanism to function in the event of the motor 50 attempting to drive the steering column too fast and/or in the wrong direction or in the case where themotor and/or gear box have seized.The torque sensor 20 is preferably an assembly including a short sensor shaft on which is mounted a strain gauge capable of accurately measuring strain in the sensor shaft brought about by the application of torque within a predetermined range. Preferably the predetermined range of torque which is measured is 0-lONm; more preferably is about l-5Nm.Preferably the range of measured torque corresponds to about 0-1000 microstrain and the construction of the sensor shaft is chosen such that a torque of 5Nm will result in a twist of less than 2° in the shaft, more preferably less than 1 ° .Preferably the strain gauge is a SAW resonator, a suitable SAW resonator being described inWO91/13832. Preferably a configuration similar to that shown in Figure 3 of WO91/13832 is utilised wherein two SAW resonators are arranged at 45°to the shaft axis and at 90°to one another. Preferably the resonators operate with a resonance frequency of between 200-400 MHz and are arranged to produce a signal to the controller 40 of 1 MHz ± 500 KHz depending upon the direction of rotation of the sensor shaft. Thus, when the sensor shaft is not being twisted due to the absence of torque, it produces a 1 MHz signal. When the sensor shaft is twisted in one direction it produces a signal between 1.0 to 1.5 MHz. When the sensor shaft is twisted in the opposite direction it produces a signal between 1.0 to 0.5 MHz. Thus the same sensor is able to produce a signal indicative of the degree of torque and also the direction of rotation of the sensor shaft. Preferably the amount of torque generated by the motor in response to a measured torque of between 0-10Nm is 0-40Nm and for a measured torque of between l-5Nm is 0-25Nm.Preferably a feed back circuit is provided whereby the electric current being used by the motor is measured and compared by the controller 40 to ensure that the motor is running in the correct direction and providing the desired amount of power assistance. Preferably the controller acts to reduce the measured torque to zero and so controls the motor to increase its torque output to reduce the measured torque. A vehicle speed sensor (not shown) is preferably provided which sends a signal indicative of vehicle speed to the controller. The controller uses this signal to modify the degree of power assistance provided in response to the measured torque. Thus at low vehicle speeds maximum power assistance will be provided and a high vehicle speeds minimum power assistance will be provided。

电气工程及其自动化专业毕业论文外文翻译

本科毕业设计（论文）中英文对照翻译院(系部) 工程学院专业名称电气工程及其自动化年级班级 11级2班学生姓名蔡李良指导老师赵波Infrared Remote Control SystemAbstractRed outside data correspondence the technique be currently within the scope of world drive extensive usage of a kind of wireless conjunction technique，drive numerous hardware and software platform support。

Red outside the transceiver product have cost low，small scaled turn, the baud rate be quick，point to point SSL，be free from electromagnetism thousand Raos etc. characteristics，can realization information at dissimilarity of the product fast，convenience, safely exchange and transmission, at short distance wireless deliver aspect to own very obvious of advantage. Along with red outside the data deliver a technique more and more mature，the cost descend，red outside the transceiver necessarily will get at the short distance communication realm more extensive of application。

自动化专业毕业设计外文翻译--输入力矩受限的机器人鲁棒自适应控制

外文文献原文Limited torque input Robust Adaptive Tracking Control ofRobotAbstractBased on input constraints, a novel robust-adaptive tracking control algorithm is proposed for robot manipulators since stability if the standard adaptive control system is problematic when some disturbance exists. The proposed controller stabilizes the system with some disturbance and guarantees asymptotic stability in the case if non-disturbance. Robust-adaptive algorithm can be received as the extension of the conventional adaptive scheme. The estimated parameters enter the controller non-linearly and the resulting closed-loop system. The algorithm provides further flexibility fir adaptive controller design and better transient performance and robustness to disturbance and error of estimated parameter-region especially. Simulation results demonstrate it effectiveness.Keywords: Adaptive control; robot manipulator; parametric uncertainties; robust-adaptive;So far, almost all of the controller design is based on joint drive to produceany torque on the basis of; and is subject to the physical conditions, the output of the drive torque is limited, so the controller may lead to the control failure or deterioration of the quality control.Therefore the controller design must take into account the limited joint drive dynamic capability.For example, the operation of the industry to help the robot, some parameters are uncertain or unknown, adaptive control is based on the estimated parameters to deal with such issues one of the main control strategy, using the robot dynamic equations of linear parametric nature, through an integral operator estimates the robot parameters. As integral part of the role in the continued interference conditions, stability control system is not easy, so appropriate to limit or adjust the integral part of the role of the adaptive system to achieve an effective means of stabilization. Son ah estimated parameters can limit the extent required, thereby increasing the robustness of adaptive control system. However, this algorithm has six switch component, a little complicated, but really is the parameter is not specified range, it cannot give the system control quality and robustness of information.This paper presents a simple robust adaptive control algorithm, when the estimated parameters field contains the parameters of the true value, the closed-loop system to achieve asymptotically stable tracking; when there is interference or the estimated parameters with the true value of free parameter that is when the error system is stable.1. MANIPULATOR DYNAMIC MODEL AND CHARACTERISTIC MODELConsider a robotic manipulator with n degrees of freedom. The continuous Lagrange dynamic model is given by()(,)()M q q C q q q G q u ++= Where q ∈R n and q ∈R nare the vector of generalized joint coordinates and velocity coordinates, respectively. The inertia matrix M(q)-M T (q)> 0 ，and there exist two constant positive scalars M min and M max such that minM ≤M ≤max M , nu R ∈is the vector of commanded generalized force, and (,)C q qq andG(q) are the terms due to Carioles, Centripetal and gravity forces. In actual application, the uncertain parameters and un-modeled dynamics usually exist in the established dynamic model in (1).When the sample time sT is small enough, at instant t=k s T q and q can be approximated by()(1)s q k q k q T --≈ and 2(1)2()(1)s q k q k q k qT +-+-≈ . Respectively Using the above relationships thediscrete-time representation of (1) becomes ()()()()()()()()()()12211S M q k q k f k q k f k q k G k u k T '∙+--+=(2a) Premultiplying(2a) by ()()21sT mM q k -results in()()()()()()()()1211q k f k q k f k q k G k k u k β'+---+- where()()()()()()112,s f k I T M q k C q k qk -=- , ()()()()()()12,s f k I T M q k C q k qk -=-+ ()()()()()()()()2121s s G k T M q k G q k k T Mq k β--'==and I denotes the unitary diagonal matrix with an appropriate dimension.If the designed (),,u t q q (),,u t q q is continuous in t ,q and q , then the solution (q,q ) of (1) will be continuously differentiable. Let()()()1,,W q qM q C q q -= and (),ij w q q be ij-th element of matrix (),ij W q q ; We define()()()()11111SF k f k f k T =--and then ΔF1(k) can be expressed as()()()()()()()1,1,1F k W q k qk W q k q k =--- For the ij-th element Δf1,ij(k) of matrix ΔF1(k)we can get()()()()()()()()1,,1,1ij ij ij f k w q k qk w q k q k =---- =()()()()()()()1111,|1ij q q k T qq k w q qq k q k q ςς=-=-∂---∂()()()()()()()1111,|1ij q q k T qq k w q qq k q k q ςς=-=-∂---∂ =()()()()()11211,|1ij s q q k T qq k w q q T q k q ςςς=-=-∂--∂ ()()()()()11311,|1ij s q q k T qq k w q qT q k q ςςς=-=-∂--∂with 0≤1ς≤1,and 2ς,3ς≈1 for a small sample time Ts . From (3), it can beseen that ΔF1(k)→0 as Ts converges to zero in a compact set of (),q q(),q q.Similar properties can also be achieved for the coefficient matrixes f2(k),()G k '()G k ' and β (k) .In a compact set of (),q q, the following properties can be deduced from (3)and the expressions of the coefficient matrixes of (2b):Property 1: If the sample time Ts is small enough,then all coefficient matrixes of (2b) are slowly time varying;Property 2: f1(k)→2I,f2(k)→ −I and f1(k)+f2(k)→I, as the sample time Ts converges to zero. Then we can define the discrete equation (2b) with Properties 1 and 2 as the robotic manipulator characteristic model.2. MULTI-VARIABLE GSA CONTROLLER WITH NN COMPENSATIONDiscrete equation (2b) can be expressed as follows:()()()()1T q k k k e k θφ+=+()()()()1T q k k k e k θφ+=+ (4) Where()()()()()12,,,Tk f k f k k G k θβ'=⎡⎤⎣⎦,()()()(),1,,1TT T T Tk q k q k u k φ⎡⎤=--⎣⎦,e(k) denotes the vector of white noise with zero mean. In the case of ()G k ' ≡0, ()k θand ()k φ can be reduced to()()()()12,,Tk f k f k k θβ=⎡⎤⎣⎦()()()(),1,,TT T Tk q k q k u k φ⎡⎤=-⎣⎦Then the elements of q(k +1) can be expressed as()()()()1i i j q k k k e k φθ+=+ (5)wherei = 1,…,n, i q (k+1)) is the element i of q(k +1), ()i e k is the element i of e(k) and ()i k θ is the column i of the matrix()()()()()()()()()()()11111T T TP k k k P k p k k p k k k P k k φφλλφφ-⎡⎤--=∙--⎢⎥+-⎢⎥⎣⎦()k Θ . When the coefficient matrixes are unknown, it can be estimated by()ˆk Θ=π (q(k),q(k−1),...,u(k−1),...) , (6a) where ()ˆk Θis the estimated coefficie nt matrix of Θ(k) at the instant t=kTs , and ()π∙ denotes an estimation operator. Considering the coefficient matrixesof the characteristic model being slowly time-varying, we can obtain the selected estimation operator by the weighted least squares method (WLS)[13], namely()()()()()()()()()()()()1ˆ111i i i i TP k k k k q k k k k k P k k φθθφθλφφ-+=+∙+-+-, ()()()()()()()()()()()11111T T TP k k k P k p k k p k k k P k k φφλλφφ-⎡⎤--=∙--⎢⎥+-⎣⎦with λ(k+1)=μ0λ(k)+(1−μ0), 0<μ0 ≤1, and ()ˆik θ the column i of the matrix ()ˆk Θ. Given a desired smooth trajectory ()d q t , the adaptive control controller is designed as follows()()()()T G c u k u k u k u k =++ (7)with the feed forward control law designedas()()()()()()()()()()112ˆˆˆ11T d d du k k k I q k f k q k f k q k βε-=+∙+---(7a) and the multi-variable GSAC feedback law as()()()()()()()()()()11122ˆˆˆˆ1Gdu k k k I L fk q k L f k q k G k βε-'=+∙--+ (7b)where ()()()d qk q k q k =- is the tracking error andε(k) >0 is a small scalar that avoids the estimated matrix ()ˆk β being singular. The term of ()cu k will be designed later; L1 and L2 are golden-section coefficients, that is,210.6182L =≈130.3822L =≈, 210.6182L =≈,which satisfy the relationship L1+L2=1 and 212L L = Substituting (7) into (2), we can get()()()()()()()()22112111s c M q k q k L f qk L f q k k T u k +---=- (8)()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()()11121222122122ˆˆˆ11d s c k M q k M k q k M q k f M k f k L q k L q k M q k s k M q k L f k s k M q k L I f k f k q k k T u k M q k L f k s k =-+--++=----+-=- ()()()()()()()()()()()()()()()2212ˆˆˆˆ11d M q k f M k f k L q k L q k M q k G k M k G q k ---+-+-and ()()()()12ˆˆsM k T k k I βε-=+.Defining the tracking filtered error s(k +1) as and using the relationships L1+L2=1 and 212L L =,212L L = (8) can be expressed as()()()()()()()()()()()()()222121M q k s k M q k L f k s k M q k L I f k f k qk +=---- ()()21s c k T u k +- =()()()()22M q k L f k s k - (9)()()()()()()()()2212ˆˆˆs c M q k L I f k f k q k k T u k +--+- Which()()()()()()()()1212k k M q k L I f k f k qk =--- ()()()()()()212ˆˆˆM q k L I f k f k q k +-- Assuming ,()()()ˆM k M q k =,()()()()()11ˆˆM k f k M q k f k = and ()()()()()22ˆˆM k f k M q k f k =,if ()c u k is selected as ()()()()()()()2212ˆˆˆc s u k T M q k L I f k f k q k -=-- then Δ(k) = 0 , and then (9) can be written as()()()221s k L f k s k +=-()()()221s k L f k s k +=- (10)Since in Property 2 ()2f k I →-()2f k I →-as Ts → 0 in a compact set of (),q q(),q q , a small sample time Ts can be selected such that the inequality ()221L f k < can be satisfied. Therefore, the tracking filtered error s(k)asymptotically converges to zero in this case. The convergence of s(k) to zero in turn guarantees the convergence of q(k) to zero. Because of the dynamics of the estimator and the time-varying coefficients of the characteristic model, it is almost impossible to satisfy the above assumptions. Therefore, we can design a suitable compensation control law ()c u k to avoid possibly the case that the control performance is deteriorated or that the close loop system is even unstable due to the estimation errors. Hence ()c u k is designed as()()()()()()()()()()()2212ˆˆˆc s i i i u k T M k L I f k f k q k k k Ty k k ψδ-=--+=+()()()111s k q k L q k +=+-()()()()()()()()2212ˆˆˆc s u k T M k L I f k f k q k k -=--+ (11) where ()ˆkis the estimate of Δ(k) . Assuming Δ(k) is smooth enough and bounded, it then can be approximated by the linearly parameterized NN to any required degree of accuracy [6,14]. Then the element Δi(k) of Δ(k) can be expressed as()()()i i i k Ty k k ψδ=+ (12)where i= 1,…n, T n i R ψψ∈ is the column i of the optimal NN weightmatrix,1T n ψψψψ⎡⎤=⎣⎦…,.Activation functions ()()(),,Tn y k y k y k ψ⎡⎤=⎣⎦… represent the basis function vector, which can be selected as any one of Gaussian radial basis, B-spine basis, Wavelet basis, and etc. [14], and δi (k) denotes the element I of the NN reconstruction error vectork δ(k), namely()()()1,T n k k k δδδ=⎡⎤⎣⎦…, .Using compensation control law ()c u k , (9) can be written as ()()()()()()()221M q k s k M q k L f k s k +=-()()11ˆˆ,Tn n y k k ψψψψψψδ⎡⎤+--+⎣⎦… (13) Where ()ˆi k ψis the estimate of i ψ, and ()max sup i kk ψδδ=<∞ An estimate ()ˆi k ψis now obtained by minimizing the cost function ()()()()1112T J s k M q k s k =++ (14)After substituting (13) into (14), the gradient of the cost function in (14) is derived as()()1ˆT Jy k s k ψ∂=-+∂ (15) According to the gradient descent method the NN weight adaptation law can be designed as()()()()ˆˆ11T k k y k s k ψψα+=++ (16) with α > 0 . Then the compensation control law ()c u k in (11) can bewritten as()()()()()()()()2122211ˆˆTc s su k M k L I f k f k qk k y k T T ψ=--+ (17) In view of the case ()()12ˆˆ0I fk f k --≈ the term ()cu k can be simplified as()()()21ˆTc su k k y k T ψ=4. SIMULATION RESULTSConsider a planar, two-link, articulated manipulator as in [3] (as presented in Fig. 1), whose dynamics can be written explicitly as()1112111212212222210M M qq u hq h q q M M q q u hq --+⎛⎫⎛⎫⎛⎫⎛⎫⎛⎫+= ⎪ ⎪⎪ ⎪ ⎪⎝⎭⎝⎭⎝⎭⎝⎭⎝⎭Where122123242cos sin M M a a q a q ==++ 11132322cos 2sin M a a q a q =++ 222M a =3242sin cos h a q a q =-With 22211111c e e ce e a I m l I m l m l =++++,22e e ce a I m l =+31cos e ce e a m l l δ=,41sin e ce e a m l l δ=,111,1,2,30,e e m l m δ==== 110.12,0.5,0.25,c e I I I ===and 0.6ce l =. In the simulation, the sample time Ts = 2ms, the initial values and the parameters of the estimator and the controller are selected as P(0) =1×310I,λ(0) = 0.96 , μ0 = 0.98 , the anti -singularity factors(k) can be designed as ε(k) =5×610-exp(−kTs).According to the Property 2, the initial estimate values of the characteristicmodel coefficient matrixes are chosen as ()()12ˆˆ02,0f I f I ==-A basis set of activation function y(k) can be selected as in the Random Vector Function Link net [16], namely,()()()T y k V X k σ= (19) with V a randomly selected matrix and X(k) the NN input vector. ()σ∙can be chosen as the h yperbolic tangent function, and X(k) can be taken as()()()()(),1,,,1TT T T Td d X k q k q k q k q k ⎡⎤=-⎣⎦.The adaptation gain for the NN weight tuning is taken as α = 0.005 , and the initial values of the weights are set to zeros.The desired trajectory is chosen as()()()301cos 2,451cos 2T d q t t t ππ⎡⎤=--⎣⎦(20)外文翻译输入力矩受限的机器人鲁棒自适应控制摘要在输入力矩受限的情况下，提出一种全的简单鲁棒自适应控制算法。

自动化专业毕业设计外文翻译--使用连续小波变换在配电系统中故障定位(中文)

中文6710字毕业设计（论文）外文翻译On the use of continuous-wavelet transform for fault location in distributiong power systems使用连续小波变换在配电系统中故障定位出处：International Journal of Electrical Power & Energy Systems, 2006, 28(9): 608-617使用连续小波变换在配电系统中故障定位a a a ab a R L M A C S A 蒂纳雷利布莱特保罗努奇科希博尔盖蒂.,.,.,..,.,.,*a 意大利波洛尼亚viale Risorgimento 2，40136波洛尼亚大学电气工程系，b 意大利米兰 CESI收于2006年3月31日;接受2006年3月31日摘要该论文说明了连续小波变换（CWT ）为分析由于线路故障引起电压瞬变得基本步骤并讨论了其应用于配电系统故障定位。

所进行的分析实现在网络中显示存在相关典型频率的连续小波变换转换信号和特殊路径代替转换小波引起的故障。

本文提出了一种在MV 离散系统中利用以上所提到的相关性确定MV 配电系统故障定位的步骤。

在本文中分析MV 离散系统是准确地以EMPT 模型为代表，以及研究各种故障类型和网络特点。

本文介绍了一些也基本测量概念和故障定位标准系统的分布式结构。

关键词：故障测距;配电系统;连续小波变换;电磁暂态;分布式测控系统1. 导言近年来中压配电网络的故障定位是一个日益受到重视研究话题，由于既要最严的质量的要求并要提供改进测量和监测系统。

此外，在网络需检修的传统程序的基础上增加的安装分布式发电资源自动开关系统。

最有前途的解决这个大家关注问题的方法似乎是在离散系统中运用适当的信号处理技术引起电压/电流瞬变产生的短路事件并记录在一个或更多的位置。

毕业设计方案英文翻译(译文)

编号：毕业设计(论文>外文翻译<译文）学院：机电工程学院专业：机械设计制造及其自动化学生姓名：赵盛伟学号： 0801120319指导教师单位：桂林航天工业学院姓名：梁伟职称：高级工程师2018 年 5 月 15 日数控车床第一课现代数控车床的组成车床是一种能将工件毛坯上多余的材料切除掉的机床，毛坯被安装在主轴上并绕主轴旋转。

这种机床主要用来加工旋转零件的表面和端面。

在所有的金属切削中，大多数都采用锋利的单刃刀具，现代数控车床刀具被牢固地固定在转塔刀架上，使其准确地移动。

转塔刀架有自动换刀功能，用来快速将旧刀换出并将新刀换至其切削位置。

前刀架将刀具从主轴轴线之下上移至工件，而后刀架则将刀具从主轴轴线之上移至工件。

因此，有前后刀架的车床，可以从工件的上方和下方同时进行切削。

车床主要是为了进行车外圆、车端面和镗孔等项工作而设计的机床。

车削很少在其他种类的机床上进行，而且任何一种其他机床都不能像车床那样方便地进行车削加工。

由于车床还可以用来钻孔和铰孔，车床的多功能性可以使工件在一次安装中完成几种加工。

因此，在生产中使用的各种车床比任何其他种类的机床都多。

车床的基本部件有：床身、主轴箱组件、尾座组件、溜板组件、丝杠和光杠。

床身是车床的基础件。

它常是由经过充分正火或时效处理的灰铸铁或者球墨铁制成。

它是一个坚固的刚性框架，所有其他基本部件都安装在床身上。

通常在床身上有内外两组平行的导轨。

有些制造厂对全部四条导轨都采用导轨尖朝上的三角形导轨<即山形导轨），而有的制造厂则在一组或者两组中采用一个三角形导轨和一个矩形导轨。

导轨要经过精密加工以保证其直线度精度。

为了抵抗磨损和擦伤，大多数现代机床的导轨是经过表面淬硬的，但是在操作时还应该小心，以避免损伤导轨。

导轨上的任何误差，常常意味着整个机床的精度遭到破坏。

主轴箱安装在内侧导轨的固定位置上，一般在床身的左端。

它提供动力，并可使工件在各种速度下回转。

自动化专业毕业设计英文翻译--供水专用变频器的设计和应用

DESIGN AND IMPLEME.NTATION OF A VARIABLE FREQUENCY REGULATORY SYSTEM FOR WATER SUPPL YABSTRACTThe designs of the variable frequency constant pressure water supply for a single hydraulic pump and high power multiple hydraulic motors systems are presented in this paper. This system can save energy by controlling the speed of the pipe motors which depend upon the number of consumers in use. This system was also uccessfully implemented in most of the modern buildings in. Shanghai, China. Finally, the choice criteria for variable frequency regulators for water supply system will be discussed.INTRODUCTIONIt is inevitable to install high level water storage systems or reservoirs for a multiple story building or residential areas. This kind of system results in increasing construction cost and cleaning problems. Nevertheless, hydraulic pumps are used toraise the energy level of the water. The conventional high level reservoir system is in fact a pressure regulatory system. This pressure (head) is proportional to the height of the reservoir. Resistance of pipes is varying from time to time. When number of users increases, that means number of relief valves to be open is increased. It in turn reduces the resistance of the pipes. In order to reduce the construction cost, eliminate the cleansing problem of the high level reservoirs, and make the system simple, a variable frequency constant pressure closed loop system is presented to control the speeds of the hydraulic pumps.In this paper, the designs of the variable frequency constant pressure water supply for a single hydraulic pump and high power multiple hydraulic motors systems are presented. From static characteristics of water flow system, the critical point canbe obtained to achieve the minimization of energy consumed. The implementation of this system is also discussed. The choice of variable frequency regulators for water supply system is finally presented.ADVANTAGESOFTHEPROPOSEDSYSTEMIn short, the advantages of this proposed variable frequency constant pressure system for water supply are1. In a 3 hydraulic motors system, the capacity of the variable frequency regulator is just one-third of the capacity of the overall system. The cost is much reduced.2. Since the system consists of multiple pumping motors, they can be controlled by PLC such that the system is more reliable.3. Energy saving can be achieved by controlling the speed of pump motors, pressure can be kept constant no matter what water flow is (from zero to its maximum capacity)4. Each pumping imotor can be started smoothly by using this variable frequency regulator, it reduces pulse current. This kind of water supply system could become a new trend in modern multiple-story building design.PRINCIPLE OF OPERATIONThe principle of operation was initially illustrated by a single pump system. Fig. 1 shows a block diagram of a variable frequency constant pressure system which is suitable for single pump or small scale water flow system. The model type is JS.5-P1. The pressure sensor (PS) transducers the water pressure in pipes to e1ectrical signals. This signal will go to pressure regulator (PR) through an amplifier (A)and a comparator compared with the set value of waterpressure. The difference will come to the PID control to regulate the output frequency as well as the speeds of electric motors and hydraulic pumps. The constant pressure can then be achieved. Fig. 2 shows static characteristics of this constant pressure water supply system. Curves 1 and 2 represent relationship between the pressure head (H) and flow rate (Q) for different speeds of the pump. Curves 3 and 4 represent for different values of resistance of pipe. To simply the exposition, per unit values are adopted in the Fig. 2. Hence,H*=H/H N, Q*=Q/Q Nwhere H N and Q N are the set values of head and flow rate.In this system, both flow rate and the resistance of pipes are varying because the flow rate is proportional to number of valves to be opened. Curve 3 represents the resistance of pipe when the flow rate reaches the maximum point. It intercepts with the H* - Q* at point a , which is the set point for operation. Curve 4is for resistance of pipe when the flow rate is less and only part of valves to be opened.If there is no frequency regulator, it works at point b' only. At this moment, the head pressure exceeds the set value. The flow rate Q is proportional to the speed of the pump, n. Head pressure H is thus proportional to the square of the speed, n2. The speed of the pump can be controlled by the frequency regulator. It becomes the curve 2, which intercepts curve 4at point b, it is a new set (working) point. At this time, the set speed should be n*= n/nN = K (K<l). Obviously, the point b is lower than point b'. It in turn means that H at point b is less than that at point b'.Hb < Hb'It achieves the purpose of energy saving.FURTHER MODIFICATIONThis JSS-P1 model was suitable for single pump water supply system. When the flowrate is little, the pressure can be much reduced. For example, Hp* varies from 1 to Hp-* which is less than 1 (Hp-* < 1). It is able to save much energy. From thisworking principle, it was modified to suit a large scale multiple pumping water supply system. A new model of JS5-P2 was then developed. Fig. 3shows a block diagram of a variable frequency constant pressure system consisting of 3 same capacity pumps. It was modified from the JSS-P1 model. It is designed for multi- pumps water supply system which programmable logic control (PLC) is involved such that the number of hydraulic motors in operation can be determined by the flow rate. The rest of motors are in stand-by mode and the energy saving can be realized. From Fig. 3, the system was composed of pressure sensor (PS), pressure amplifier (A), pressure regulator (AP), signal identifier (AI), programmable logic control (PLC), and frequency regulator. The main feature of this system is that one set of variable frequency regulator is in use to control one hydraulic motor. The rest is idling at starting. If the water flow is within the preset range. This motor is running according its characteristic curve. When the flow rate is increased, The second motor will be smoothly started. The preset value of pressure in pipes can be maintained. There arethree values for operating these motors, 0-33.3%, 33.3-66.6% and 66.6-100%.In brief, the first pump motor will work if the flow rate falls within 33.3% of operation. The operating region is within curves 1 and 4in the Fig. 4.When the flow rate increases, beyond 33.3%, frequency regulator keeps the output frequency at 50 Hz, PLC will control of on-off state of the motors such that the first pump motor is supplied by the mains. The speed of the first pump motor runs at rated speed. The frequency regulator also set the second pump motor in stand-by mode. The operating region of the second motor is within curves 2and 5in the Fig. 4.When the flow rate is continuously increased and beyond 66.6%, and the frequency regulator reaches its rated frequency 50 Hz, PLC will command the second motor to connect to the mains again and the third one at stand-by mode. The operating region of the third one fallswithin curves 3and 6 in the Fig. 4. If the flow rate is reduced from 66.6% to 33.3%, PIX will command to one of the pump motors cut off from the mains. When the flowrate further reduces, and less than 33.3%, there will be only one motor connected to the mains. From the working principle, the three pump motors are operated in turnto meet the requirement of energy saving.CRITERIA FOR FREQUENCY, REGULATORFor the load of the hydraulic pump, the torque is proportional to the square of the motor speed, it is also proportional to the square of the supply frequency, f2. To a electric motor, the torque is equal to C m *Φm*I2*cosα, where C m, is a constant, Φm, is the magnetic flux of rotating field, I2 is the rotor current, and cosα is the power factor of rotor circuit. I2normally cannot exceed its rated value.If the voltage drop in the stator is negligible, $, will be proportional to supply voltage V. In order to maintain, the supply voltage V should be required to be proportional to the square of the frequency. Therefore, the characteristic of V versus f should be set to be a quadratic relationship.CONCLUSIONThis type of variable frequency constant pressure closed loop system for water supply was designed and implemented in Shanghai, China. The performance was proven satisfactory. A copy of a photograph of this system was shown in Fig. 5. All four advantages of this proposed system were fully realized. This system is one of the energy saving methods in tall building design.Automation System S7-300:Getting Started CPU 31xC: Commissioning1. Step: Installing the mounting rail and modulesRail installation sequenceFrom left to right: Power supply PS 307 - CPU 313C.The synopsis will provide you with an overview of the overall configuration.Install and ground the mounting rail1. Screw on the mounting rail (screw size: M6) so that at least 40 mm space remains above and below the rail. When mounting it on a grounded metallic panel or on a grounded device mounting panel made of steel sheet, make sure you have a low impedance connection between the mounting rail and the mounting surface.2. Connect the rail to the protective conductor. An M6 screw is provided on the rail for this purpose. Minimum cross-section from the cable to the protective conductor: at least 10 mm2. Installing modules on the mounting rail1. Hook the power supply module onto the rail, slide it until it reaches the grounding screw of the rail and then screw it tight.2. Hook the CPU onto the rail (1),slide it along as far as the module on the left (2), and swing it down into place (3).3. Bolt the CPU tight, applying a torque of between 0.8 and 1.1 Nm.4. Insert the micro memory card into the CPU (4); this is essential for operation. If you do not know the content of the micro memory card, erase it first on the programming device.2. Step: Wiring modulesWiring the power supply and the CPU1. Open the front panel covers of the power supply module and CPU.2. Unscrew the strain relief clamp on the power supply module.3. Remove the insulation from the power cord, attach the cable end sleeves (for stranded conductors), and connect them to the power supply.4. Screw the strain-relief assembly tight.5. Insert two short connecting cables between the power supply and the CPU and screw them tight.6. Check that the line voltage selector switch is set to the correct line voltage.The default line voltage setting for the power supply module is 230 VAC. To label a front connector, follow the steps outlined below: To change the voltage, remove the protective cap with a screwdriver, set the switch to the required line voltage and replace the protective cap. Wiring the front connectors of the DI and DO1. Open the right front panel of the CPU 313C.2. Place the front connector into wiring position. You do this by pushing a front connector into the CPU until it latches. In this position, the front connector still protrudes from the CPU. In the wiring position a wired front connector has no contact with the module.3. Remove 6 mm of the insulation from the ends of the wires that go into the front connector. Attach cable end sleeves to these ends.4. Wire the front connector (DI side) as follows:– Terminal 1: L+ of the power supply– Terminal 3: Button 1– Terminal 4: Button 2– Terminal 20: M of the power supply5. Wire the front connector (DO side) as follows:– Terminals 21 and 31: L+ of the power supply– Terminal 30: M of the power supply.6. Wire the free cable ends of the button with L+ of the power supply.7. Lead the wires downwards out of the front connector.8. Secure the front connector with the screws (this establishes contact with the module).9. Close the front panel covers of the power supply module and the front panel of the CPU.3. Step: Commissioning hardwareProcedure1. Use the PG cable to connect the programming device to the CPU. When using a cable with PROFIBUS connectors, remember to switch on the integrated terminating resistors. Close the front panel cover of the CPU, then set the mode selector switch on the CPU to STOP.2. Connect the mains cable, then switch on the power supply module PS 307.The DC24V LED on the power supply is lit. All the LEDs on the CPU light up briefly; the SF LED and the DC5V LED stay lit. The STOP LED then flashes slowly to indicate a CPU memory reset.3. Perform a CPU memory reset:– Turn the mode switch to MRES. Hold the mode selector at this position until the STOP LED lights up for the second time and then remains lit (approx. 3 seconds). Then release it.– You must press the mode switch back to MRES within 3 s. The STOP LED begins to flash rapidly and the CPU performs a reset. You can now release the mode switch.The CPU has completed the memory reset when the STOP LED remains permanently lit again.4. Start your programming device, then run SIMATIC Manager from your Windows Desktop.A window opens with SIMATIC Manager.5. Select button 1.The LED of I124.1 lights up. No DO LED lights up.6. Select button 2. The LED of I124.2 lights up. No DO LED lights up.4. Step: Programming the circuitProcedure1. Follow the instructions of the STEP 7 "New Project" wizard on the programming device and set up a new project with the following data:– CPU type: CPU 313C– Block to be created: OB 1– Project name: S7_Pro1A window, divided into two parts, opens with the title S7_Pro1 -- .2. Double-click the OB1 icon in the right-hand part of the window. The editor for editing the OB 1 block opens.3. In the "View" menu, select "LAD" to change to the ladder logic programming language. At the bottom of the left-hand window, a current path is displayed in network 1.4. Carefully click on the horizontal line representing the current path. The line is highlighted.5. On the toolbar, click twice on the --||-- icon (normally-open contact) and then once on the –( ) icon (coil). The icons are inserted into the current path.6. Click on the red question mark for the left-hand normally- open contact in the current path. The normally-open contact is highlighted and the question mark is replaced with a text input box containing the cursor.7. Enter I124.1 and press Return. The left-hand normally-open contact is now called I124.1.8. Label the right button in the same way with I124.2 and the coil with Q124.0.9. Close the editor and click Yes when you are prompted to save. The editor is closed and OB 1 is saved.5. Step: Configuring hardwareProcedure1. In SIMATIC Manager, click on SIMATIC 300 Station in the left-hand part of the window. The Hardware and CPU 313C icons appear in the right-hand part of the window.2. Double-click the Hardware icon in the right-hand part of the window.The editor for editing the hardware opens.3. If the catalog is not shown in the right section of the window, you can activate it by selecting Catalog in the View menu.4. Expand SIMATIC 300 and CPU-300 until you see CPU 313C.5. Insert the CPU 313C by dragging it to slot 2 (top or bottom left-hand window).6. Check that the order number displayed for slot 2 in the lower left-hand part of the window matches the order number of your CPU. You may need to expand the width of the order number column to see the entire number. If it does: Skip to the next step. If it does not: Expand CPU-300 in the catalog until you see CPU 313C and replace the CPU in slot 2 by dragging the CPU with the correct order number from the catalog.7. Perform steps 3 and 4 for the power supply module PS 307 too. You insert the PS 307 in slot 1.8. Go to the Station menu and select Save and compile. The hardware configuration is compiled and saved.9. Close the editor. The editor is closed.6. Step: Trial runProcedure1. Use the SIMATIC 300 station and CPU 313C to browse to the S7 program. In SIMATIC Manager click on Blocks in the right-hand part of the window. Blocks will now be highlighted.2. Select Download from the PLC menu to transfer the program and hardware configuration to the CPU. Confirm all windows with Yes. The program and configuration are downloaded from the programming device to theCPU. The program is now stored on the Micro Memory Card (in the load memory), where it is unaffected by power failures and resets.3. Set the CPU's mode switch to RUN. The STOP LED is switched off. The RUN LED starts to flash and then assumes a continuous signal.4. Press each of the buttons alternately. The LEDs of inputs I124.1 and I124.2 light up alternately. The LED of output Q124.0 is not lit.5. Press both buttons simultaneously. The LEDs of inputs I124.1 and I124.2 light up simultaneously. The LED of output Q124.0 is lit. This would switch on a connected finalcontrolling element or indicator.Further InformationDiagnostics/Correction of ErrorsWrong operation, faulty wiring or a faulty hardware configuration may cause errors which the CPU, CP or IE/PB-Link indicate with the SF group error LED after CPU memory reset. How to analyze such errors and alarms is described in the CPU31xC and CPU 31x operating instructions, Setup and Programming with STEP 7 manuals.Manuals containing further informationFor more in-depth Getting Started information, we recommend Getting Started and Exercises with STEP 7Service & Support on the InternetIn addition to our documentation, we offer a comprehensive online knowledge base on the Internet at:/automation/service&supportThere you can find:• A newsletter containing the latest information on your Siemens products.• The documents you need using our search engine in Service & Support.• the bulletin board, a worldwide knowledge exchange for users and experts.• your local contact for Automation & Drives in our contact database.• Information about on-site services, repairs, spare parts. You will find much more under "Services".第一部分供水专用变频器的设计和应用摘要:本文提出了一种用于变频恒压供水的单个液压泵和高功率多液压电机系统的设计方法。

自动化专业毕业设计外文翻译--走进数字博物馆展览智能化：模块化的框架,艺术审美的超媒体

毕业设计(论文)外文文献翻译译文一：文献出处：Int J Digit Libr (2004) 4: 64–68/Digital Object Identifier (DOI)10.1007/s00799-003-0059-3走进数字博物馆展览智能化：模块化的框架，艺术审美的超媒体摘要在目前基于Web的超媒体环境下，建设和维持一个大规模的互动展览超媒体是一项艰巨的任务。

特别是编排风格繁多的多媒体创作，非常费时费力。

我们把发展智能数字博物馆展览系统作为第一步，本文提出了一种细粒度的模块化框架即分解一个典型的超媒体造型并将其介绍成细粒式模块（FGSM）。

一个基于“单声道媒体处理程序”的超媒体文档和一个数字博物馆展览管理框架已经被设计出来用以帮助我们理解FGSM的概念。

我们已经实施了基于Web的创作系统，允许内容提供商能够有效地构建起集媒体中心，互动性，美观于一体的超媒体网站。

今后，有关的优化和约束求解技术将用来最终实现数字博物馆智能展览的目标。

关键词：数字博物馆;展览;超媒体1．简介“博物馆是人们能够探索灵感，学习和享受的地方。

他们是机构收集，维护和访问，通过文物标本展现他们的社会。

”一个博物馆的基本任务包括收集，保存，研究和教育。

所有这些活动汇集在博物馆展览的公共展坛，目前这些都是博物馆对公众的主要吸引力。

同样，数字博物馆也是意料中必须建设的大型虚拟展览，实现高层次出席。

虚拟展览的主题基本上是一个编舞介绍数位典藏文物。

不论对身体还是虚拟博物馆展览的发展都是一个多学科的任务，通常需要观众专家，内容专家，通信专家和技术专家的积极参与。

由于参观者对博物馆的欣赏模式展览包括思考，理解，发现的相互作用，虚拟展览设计预计将超越只是提供单调平原网页的最终用户。

相反，考虑到美学展览需要提供先进的多媒体演示。

数字博物馆展览网站还必须考虑信息技术可用性优势，提高参与一个互动的个人设置。

然而，在当前基于Web的超媒体环境中，建设和维持一个大规模的吸引力展览的互动超媒体是复杂和困难的。

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中英文翻译Classification of control systems there are three ways: by automatic classification methods in order to participate in the control mode classification, to adjust the law category.One way to control category 1, the open-loop control system if the computer output of open loop control system to exercise control of the production process, but the control results --- the state of the production process does not affect the computer control systems, computer \ controller \ production and other sectors does not constitute a closed loop, is called open-loop control system computer. the production process of the state is no feedback to the computer, but by the operator to monitor the status of the production process, decision control program, and tell the computer to control the role of exercising control. 2, closed loop control system computer to the production of an object or process control, the state can directly influence the production process computer control system, called the closed-loop control system computer. Control of the computer monitor in the operator, the automatic acceptance of the production process state test results, calculate and determine the control scheme, the direct command and control units (devices> of action, the role of exercising control of the production process. In such systems, aircraft control components under control of control information sent to control device operation, the other running equipment condition as the output, measured by the detection part, the feedback as input to the control computer。

to make control Computer \ Control Components \ production \ test components form a closed loop. We will call this form of control computer control closed-loop control. Closed loop control system computer, using a mathematical model to set the value of the production process and test results of the best value of the deviation between the feedback and control the production process to run at their best. 3, line control system as long as the computer controlled production of the controlled object or process, to exercise direct control, without human intervention are called the control computer on-line control, or on-line control system. 4, offline control system control computer does not directly participate in the control object or the controlled production process. It only managed to complete the process of the controlled object or the status of testing, and testing of data processing。

and then develop control programs, the output control instruction, operator reference control instructions manually controlled operation to control parts of the object or subject control process control. This control form is called off-line computer control system. 5, real-time control system control computer real-time control system iscontrolled by the control of the object or process, or request when the request processing control, the control function in a timely manner to address and control systems, commonly used in the production process is interrupted for the occasion. Such as steel, each one refining furnace steel is a process。

and if the process rolling, rolling out each piece of steel considered a process, each process is repeated. Only enter the process only requires a computer control. Once control of the computer, it requires a computer from the production process information in the required time to respond to or control. Such systems often use sophisticated interrupt system and interrupt handling procedures to achieve. In summary, an online system is not necessarily a real-time system. But a real-time system must be an online system.Second, in order to participate in the control mode to Category 1, direct digital control system by the control computer to replace conventional analog instruments and direct regulation to control the production process, as the computer as digital signals, so named after the DDC control. Actually controlled the production process control components, control signals received by the process controller input / output channels of D / (D / A> converter output of the digital control computer volume to be converted into analog。

analog input control machine to go through the process of input / output channels of analog / digital (A / D> converter into a digital number into the computer. DDC control systems often use a small computer or microprocessor, the time-sharing system to achieve multiple points of control. Is in fact a discrete sampling with the controller, to achieve discrete multi-point control. DDC computer control system that has become the main control computer control system forms. DDC control of the advantage of flexibility, large, focused on high reliability and low cost. Can use several forms of digital computing circuits, or even dozens of loop production process, integral to proportional --- --- differential (PID> control to maintain the industrial state of the controlled object at a given value, the deviation small and stable. And as long as the change of control algorithms and applications can achieve more complex control. Such as feedforward control and the best control. Under normal circumstances, DDC-level control often more complex as the implementation of advanced control level. 2, supervisory computer control system supervisory computer control system for a particular production process, according to the production process of various states, according to the production process of the mathematical model to calculate the best production equipment should be running a given value, and the best value automatically or manually on the DDC Executive-level computer or analog meter to align the regulation or control of the target set. By a DDC or adjust the instrument at various points on the production process (running equipment> to exercise control. SCC system is that it can guarantee the production process is always controlled the situation in the best condition to run, so get the most benefit. SCC results directly affect the merits of the first of its mathematical model, this should always improve the operation process model, and modify the control algorithm, and application control procedures. 3, multi-level control systems in modern manufacturing enterprises in the production process not only the need to address the problem of online control, and Huan Zhi Li called for a solution of production problems, the daily product line, the number of arrangements for planning and scheduling, and Rose plans develop a long term planning, notice Xiaoshou prospects, there was multi-level control system. DDC class is mainly used for direct control of the production process, for PID, or feedforward control。