步进电机控制系统外文翻译
国家工程仪器(National Instruments)步进电机控制系统说明书
National Instruments. The boards control six stepper motors independently. T wo National Instruments UMI motion inter-face modules provide the interconnection point between the motor control boards and the stepper motors.We use a stepper motor to depress the switch from its off position to full-on position while current readings are made at both loca-tions. Initially, we program the stepper motor to slowly release the trigger, in 0.003-inch steps, from its full-on position to the position where the software detects breakthrough current. At this breakthrough (or tease)point, full current is flowing through the tips of the switch contacts, which causes arcing.T o simulate the user’s finger vibrating under fatigue on the trigger switch, the stepper motor toggles forward and back around the tease point at a user-specified distance and frequency. The minimum tease distance of the system is 0.001 in.Data Acquisition HardwareOne of the advantages of a PC-based system is the availability of plug-in data acquisition (DAQ) boards. We chose the National Instruments AT-MIO-64E-3 multipurposeby Jacquelyn Batson, MicroCraft CorporationThe Challenge: Rigorous,flexi-ble,automated life-cycle batch testing of AC and DC switches with varying voltage and current capacities.The Solution: Developing a PC-based system using National Instruments ValueMotion Stepper and DAQ boards controlled by LabWindows/CVI.IntroductionThe primary reason for testing consumer products is customer satisfaction. Early fail-ures on consumer products not only can damage product reputation with customers,but also can result in costly field returns for the manufacturer. These were two of the factors that led Black & Decker, Inc. to install a system to perform life-cycle testing on the trigger switches used in their power tools and other consumer products. They contracted with MicroCraft Corporation to develop a flexible PC-based system that uses National Instruments DAQ boards controlled by LabWindows/CVI.Specifically, Black & Decker was interest-ed in the analysis of switches undergoing a process called “teasing.” Rick Sharpe at Black & Decker reported, “We have found that a major contributor to switch failures on power tools is a user practice we call ‘teasing.’T easing results when the operator relaxes the pressure on the trigger switch to the point where the switch contacts are barely making contact, forcing the full tool current throughthe edge of the switch contact. T rying to duplicate this failure mode using operators would require an excessive expenditure of technician time and, most importantly,would not provide the consistent data we require.”Life-cycle testing of any type requires a robust test system. With a single test often taking several days, Black & Decker invests a lot of machine hours as well as man-hours testing each product. As a result, our chal-lenge at MicroCraft was to develop a system that could withstand the rigors of continuous use and smoothly handle catastrophic events such as power outages with no loss of data and minimal interference with the test in progress. The system also needed to run sev-eral test stations independently to simultane-ously test AC and DC switches with varying voltage and current characteristics.Motion ControlThe primary component of the Black &Decker switch test system is motion control.T o test six switches simultaneously, we decid-ed to use six Oriental Motor stepper motors controlled by two multiaxis ValueMotion PC-Step motor control boards fromAutomated Life-Cycle Testings DAQs LabWindows ™/CVI s ValueMotion™Life-Cycle Testing of Spring-Loaded Switches Using Motion, DAQ, and LabWindows/CVIT he primary component of theBlack & Decker switch test system is motion control.To test six switches simultaneously,we decided to use six Oriental Motor stepper motors con-trolled by two multiaxis ValueMotion PC-Step motor control boards from National Instruments.Main Panel of Automated Switch Test System Showing All Six StationsSC-2070 termination breadboard to provide connections to the analog signals because it provides a cold-junction reference signal for the thermocouple input.System SoftwareWe chose National Instruments LabWindows/CVI as our software environment. With its special features, we could satisfy the requirements for a graphical user interface and yet main-tain the speed necessary to test six switches simultaneously. The flexible LabWindows environment also made it easy to incorporate on-line help and a manual control ing the manual control mode, Black &Decker engineers can use the system as a laboratory tool for characterizing newDAQ board and AT-AO-6 analog output board; these DAQ boards easily handle the high-speed measurements and control signals. For each switch under test, the system acquires load, no-load, and locked-rotor current measurements; temperature measurements; and voltage measurements.The system also uses analog outputs to drive hysteresis brakes (or dynamometers) that apply load. We used the National Instrumentsswitches, in addition to its customary use as a test system. The system stores all test data points and test setup information to file in standard spreadsheet or SPC-compatible format. T o simplify backups and data analysis,all files are accessible over Black & Decker’s network via a plug-in Ethernet board.SummaryWith the automated switch test system, Black & Decker can perform consistent, reliable testing on the large variety of switch-es used in their consumer products and can maintain standardized test data. Black &Decker has saved thousands of man-hours thanks to the speed, accuracy, and data stor-age capabilities of the National Instruments-based system. In addition, because of the inherent flexibility of the system, we easily added the manual mode –as a result, Black & Decker received a laboratory analysis tool as well as an automated life-cycle test system.1For more information, contact Jacquelyn Batson,MicroCraft Corporation,3209-154 Gresham Lake Road, Raleigh, NC 27615tel (919) 872-2272, fax (919) 872-5822 **********************W e chose the National InstrumentsA T-MIO-64E-3 multipurpose DAQ board and A T-AO-6 analog output board; these DAQ boards easily handle the high-speed measurements and control signals.B lack & Decker has saved thousandsof man-hours thanks to the speed,accuracy,and data storage capabili-ties of the National Instruments-based system.In addition,because of the inherent flexibility of the system,we easily added the manual mode –as a result,Black & Decker received a laboratory analysis tool as well as an automated life-cycle test system.Control Panel for T est StationU.S.Corporate Headquarters • Tel:(512) 794-0100 • Fax:(512)683-9300•****************•Branch Offices:Australia 03 9879 5166 • Austria ***********•Belgium 02 757 00 20 • Brazil 000 811 781 0559 • Canada 905 785 0085 • China ***********• Denmark 45 76 26 00Finland 09 725 725 11 • France 01 48 14 24 24 • Germany 089 741 31 30 • Greece 30 1 42 96 562 • Hong Kong 2645 3186 • India 91805275406 • Israel 03 6120092 • Italy 02 413091Japan 03 5472 2970 • Korea 02 596 7456 • Mexico 001 800 010 0793 • Netherlands 0348 433466 • New Zealand 09 914 0488 • Norway 32 27 73 00 • Singapore 2265886 • Spain 91 640 0085Sweden 08 587 895 00 • Switzerland 056 200 51 51 • Taiwan 02 2377 1200 • U.K.01635 523545© Copyright 1999 National Instruments Corporation.All rights reserved.Product and company names listed are trademarks or trade names of their respective companies.361589A-01 051099。
步进电机英语介绍ppt
视频:
Closed-loop control
The closed-loop control of the stepping motor is used to determine the phase transformation, which is suitable for the position of the rotor. The accuracy and stability of the system can greatly improve the performance of the stepping motor. 步进电动机的闭环控制是采用位置反馈和
introduce:
Stepping motor is a synchronous motor with intermittent operation, which is a function of the digital control system.
步进电机本质上属于断续运转的同步电机, 是数字控制系统中的一种执行元件。
synchronous [ˈsɪŋkrənəs] intermittent operation [ˌɪntəˈmitənt ˌɔpəˈreiʃən] digital [ˈdɪdʒɪtl]
The function is to convert the input pulse signal into the corresponding angular displacement or linear displacement. The motor rotates a corner or a step. 其功用是将输入的脉冲信号转换为相应的 角位移或直线位移,给定一个脉冲信号, 电机就转动一个角度或前进一步。
【资料】步进电机和伺服电机的系统控制中英文翻译资料
【关键字】资料SELECTING THE MOTOR THAT SUITS YOUR APPLICATION Motion control, in its widest sense, could relate to anything from a welding robot to the hydraulic system in a mobile crane. In the field of Electronic Motion Control, we are primarily concerned with systems falling within a limited power range, typically up to about 10HP (7KW), and requiring precision in one or more aspects. This may involve accurate control of distance or speed, very often both and sometimes other parameters such as torque or acceleration rate. In the case of the two examples given, the welding robot requires precise control of both speed and distance; the crane hydraulic system uses the driver as the feedback system so its accuracy varies with the skill of the operator. This wouldn’t be considered a motion control system in the strict sense of the term. Our standard motion control system consists of three basic elements:Fig. 1 Elements of motion control systemThe motor,This may be a stepper motor (either rotary or linear), a DC brush motor or a brushless servo motor. The motor needs to be fitted with some kind of feedback device unless it is a stepper motor.Fig. 2 shows a system complete with feedback to control motor speed. Such a system is known as a closed-loop velocity servo system.Fig. 2 Typical closed loop (velocity) servo systemThe drive,this is an electronic power amplifier that delivers the power to operate the motor in response to low-level control signals. In general, the drive will be specifically designed to operate with a particular motor type –you can’t use a stepper drive to operate a DC brush motor, for instance.Application Areas of Motor TypesStepper MotorsStepper Motor BenefitsStepper motors have the following benefits:• Low cost• Ruggedness• Simplicity in construction• High reliability• No maintenance• Wide acceptance• No tweaking to stabilize• No feedback components are needed• They work in just about any environment• Inherently more failsafe than servo motors.There is virtually no conceivable failure within the stepper drive module that could cause the motor to run away. Stepper motors are simple to drive and control in an open-loop configuration. They only require four leads. They provide excellent torque at low speeds, up to 5 times the continuous torque of a brush motor of the same frame size or double the torque of the equivalent brushless motor. This often eliminates the need for a gearbox. A stepper-driven-system is inherently stiff, with known limits to the dynamic position error.Stepper Motor DisadvantagesStepper motors have the following disadvantages:• Resonance effects and relatively long settling times• Rough performance at low speed unless a micro step drive is used• Liability to undetected position loss as a result of operating open-loop• They consume current regardless of load conditions and therefore tend to run hot• Losses at speed are relatively high and can cause excessive heating, and they are frequently noisy (especially at high speeds).• They can exhibit lag-lead oscillation, which is difficult to damp. There is a limit to their available size, and positioning accuracy relies on the mechanics (e.g., ball screw accuracy). Many of these drawbacks can be overcome by the use of a closed-loop control scheme. Note: The Comp motor Zeta Series minimizes or reduces many of these different stepper motor disadvantages. There are three main stepper motor types:• Permanent Magnet (P.M.) Motors• Variable Reluctance (V.R.) Motors• Hybrid MotorsWhen the motor is driven in its full-step mode, energizing two windings or “phases” at a time (see Fig. 3), the torque available on each step will be the same (subject to very small variations in the motor and drive characteristics). In the half-step mode, we are alternately energizing two phases and then only one as shown in Fig. 4. Assuming the drive delivers the same winding current in each case, this will cause greater torque to be produced when there are two windings energized. In other words, alternate steps will be strong and weak. This does not represent a major deterrent to motor performance—the available torque is obviously limited by the weaker step, but there will be a significant improvement in low-speed smoothness over the full-step mode.Clearly, we would like to produce approximately equal torque on every step, and this torque should be at the level of the stronger step. We can achieve this by using a higher current level when there is only one winding energized. This does not over dissipate the motor because the manufacturer’s current rating assumes two phases to be energized the current rating is based on the allowable case temperature). With only one phase energized, the same total power will be dissipated if the current is increased by 40%. Using this higher current in the one-phase-on state produces approximately equal torque on alternate steps (see Fig. 5).Fig. 3 Full step currentFig. 4 Half step currentFig.5 Half step current, profiledWe have seen that energizing both phases with equal currents produces an intermediate step position half-way between the one-phase-one positions. If the two phase currents are unequal, the rotor position will be shifted towards the stronger pole. This effect is utilized in the micro stepping drive, which subdivides the basic motor step by proportioning the current in the two windings. In this way, the step size is reduced and the low-speed smoothness is dramatically improved. High-resolution micro step drives divide the full motor step into as many as 500 micro steps, giving 100,000 steps per revolution. In this situation, the current pattern in the windings closely resembles two sine waves with a 90°phase shift between them (see Fig. 6). The motor is now being driven very much as though it is a conventional AC synchronous motor. In fact, the stepper motor can be driven in this way from a 60 Hz-US (50Hz-Europe) sine wave source by including a capacitor inseries with one phase. It will rotate at 72 rpm.Fig. 6 Phase currents in micro step modeStandard 200-Step Hybrid MotorThe standard stepper motor operates in the same way as our simple model, but has a greater number of teeth on the rotor and stator, giving a smaller basic step size. The rotor is in two sections as before, but has 50 teeth on each section. The half-tooth displacement between the two sections is retained. The stator has 8 poles each with 5 teeth, making a total of 40 teeth (see Fig. 7).Fig.7 200-step hybrid motorIf we imagine that a tooth is placed in each of the gaps between the stator poles, there would be a total of 48 teeth, two less than the number of rotor teeth. So if rotor and stator teeth are aligned at 12 o’clock, they will also be aligned at 6 o’clock. At 3 o’clock and 9 o’clock the teeth will be misaligned. However, due to the displacement between the sets of rotor teeth, alignment will occur at 3 o’clock and 9 o’clock at the other end of the rotor.The windings are arranged in sets of four, and wound such that diametrically-opposite poles are the same. So referring to Fig. 7, the north poles at 12 and 6 o’clock attract the south-pole teeth at the front of the rotor; the south poles at 3 and 9 o’clock attract the north-pole teeth at the back. By switching current to the second set of c oils, the stator field pattern rotates through 45°. However, to align with this new field, the rotor only has to turn through 1.8°. This is equivalent to one quarter of a tooth pitch on the rotor, giving 200 full steps per revolution.Note that there are as many detent positions as there are full steps per rev, normally 200. The detent positions correspond with rotor teeth being fully aligned with stator teeth. When power is applied to a stepper drive, it is usual for it to energize in the “zero phase” state in which there is current in both sets of windings. The resulting rotor position does not correspond with a natural detent position, so an unloaded motor will always move by at least one half steps at power-on. Of course, if the system was turned off other than in the zero phase state, or the motor is moved in the meantime, a greater movement may be seen at power-up.Another point to remember is that for a given current pattern in the windings, there are as many stable positions as there are rotor teeth (50 for a 200-step motor). If a motor isde-synchronized, the resulting positional error will always be a whole number of rotor teeth or a multiple of 7.2°. A motor cannot “miss” individual steps – position errors of one or two steps must be due to noise, spurious step pulses or a controller fault.Fig. 8 Digital servo driveDigital Servo Drive OperationFig.8 shows the components of a digital drive for a servo motor. All the main control functions are carried out by the microprocessor, which drives a D-to-A converter to produce an analog torque demand signal. From this point on, the drive is very much like an analog servo amplifier.Feedback information is derived from an encoder attached to the motor shaft. The encoder generates a pulse stream from which the processor can determine the distance traveled, and by calculating the pulse frequency it is possible to measure velocity.The digital drive performs the same operations as its analog counterpart, but does so by solving a series of equations. The microprocessor is programmed with a mathematical model (or “algorithm”) of the equivalent analog system. This model predicts the behavior of the system. It also takes into account additional information like the output velocity, the rate of change of the input and the various tuning settings.To solve all the equations takes a finite amount of time, even with a fast processor –this time is typically between 100ms and 2ms. During this time, the torque demand must remain constant at its previously-calculated value and there will be no response to a change at the input or output. This “update time” therefore becomes a critical factor in the performance of a digital servo and in a high-performance system it must be kept to a minimum.The tuning of a digital servo is performed either by pushbuttons or by sending numerical data from a computer or terminal. No potentiometer adjustments are involved. The tuning data is used to set various coefficients in the servo algorithm and hence determines the behavior of the system. Even if the tuning is carried out using pushbuttons, the final values can be uploaded to a terminal to allow easy repetition.Some applications, the load inertia varies between wide limits – think of an arm robot that starts off unloaded and later carries a heavy load at full extension. The change in inertia may well be a factor of 20 or more, and such a change requires that the drive isre-tuned to maintain stable performance. This is simply achieved by sending the new tuning values at the appropriate point in the operating cycle.步进电机和伺服电机的系统控制运动控制,在其最广泛的意义上说,可能与任何移动式起重机中焊接机器人液压系统有关。
步进电机控制系统外文翻译
步进电机的振荡、不稳定以及控制摘要:本文介绍了一种分析永磁步进电机不稳定性的新颖方法。
结果表明,该种电机有两种类型的不稳定现象:中频振荡和高频不稳定性。
非线性分叉理论是用来说明局部不稳定和中频振荡运动之间的关系。
一种新型的分析介绍了被确定为高频不稳定性的同步损耗现象。
在相间分界线和吸引子的概念被用于导出数量来评估高频不稳定性。
通过使用这个数量就可以很容易地估计高频供应的稳定性。
此外,还介绍了稳定性理论。
广义的方法给出了基于反馈理论的稳定问题的分析。
结果表明,中频稳定度和高频稳定度可以提高状态反馈。
关键词:步进电机,不稳定,非线性,状态反馈。
1. 介绍步进电机是将数字脉冲输入转换为模拟角度输出的电磁增量运动装置。
其内在的步进能力允许没有反馈的精确位置控制。
也就是说,他们可以在开环模式下跟踪任何步阶位置,因此执行位置控制是不需要任何反馈的。
步进电机提供比直流电机每单位更高的峰值扭矩;此外,它们是无电刷电机,因此需要较少的维护。
所有这些特性使得步进电机在许多位置和速度控制系统的选择中非常具有吸引力,例如如在计算机硬盘驱动器和打印机,代理表,机器人中的应用等.尽管步进电机有许多突出的特性,他们仍遭受振荡或不稳定现象。
这种现象严重地限制其开环的动态性能和需要高速运作的适用领域。
这种振荡通常在步进率低于1000脉冲/秒的时候发生,并已被确认为中频不稳定或局部不稳定[1],或者动态不稳定[2]。
此外,步进电机还有另一种不稳定现象,也就是在步进率较高时,即使负荷扭矩小于其牵出扭矩,电动机也常常不同步。
该文中将这种现象确定为高频不稳定性,因为它以比在中频振荡现象中发生的频率更高的频率出现。
高频不稳定性不像中频不稳定性那样被广泛接受,而且还没有一个方法来评估它。
中频振荡已经被广泛地认识了很长一段时间,但是,一个完整的了解还没有牢固确立。
这可以归因于支配振荡现象的非线性是相当困难处理的。
大多数研究人员在线性模型基础上分析它[1]。
单片机控制步进电机外文文献翻译
单片机控制步进电机外文原文Stepping motor application and control stepper motor is an electrical pulse will be converted into angular displacement of the implementing agencies. Put it in simple language-speaking: When the stepper drive pulse signal to a receiver, it drives stepper motor rotation direction by setting a fixed point of view (and the step angle). You can control the number of pulses to control the amount of angular displacement, so as to achieve the purpose of accurate positioning; At the same time, you can by controlling the pulse frequency to control the motor rotation speed and acceleration,so as to achieve the purpose of speed.Stepper motor directly from the AC-DC power supply,and must use special equipment - stepper motor drive. Stepper motor drive system performance, in addition to their own performance with the motor on the outside, but also to a large extent depend on the drive is good or bad. A typical stepper motor drive system is operated by the stepper motor controller, stepper motor drives and stepper motor body is composed of three parts. Stepper motor controller stepper pulse and direction signal, each made of a pulse, stepper motor-driven stepper motor drives a rotor rotating step angle, that is, step-by-step further. High or low speed stepper motor, or speed, or deceleration, start or stop pulses are entirely dependent on whether the level or frequency.Decide the direction of the signal controller stepper motor clockwise or counterclockwise rotation. Typically, the stepper motor drive circuit from the logic control, power driver circuit, protection circuit and power components.Stepper motor drive controller, once received from the direction of the signal and step pulse, the control circuit on a pre-determined way of the electrical power-phase stepper motor excitation windings of the conduction or cut-off signal. Control circuit output signal power is low,can not provide the necessary stepping motor output power, the need for power amplifier, which is stepper motor driven power drive part. Power stepper motor drive circuit to control the input current winding to form a space for rotating magnetic field excitation, the rotor-driven movement.Protection circuit in the event of shortcircuit, overload, overheating, such as failure to stop the rapid drive and motor. Motor is usually for the permanent magnet rotor, when the current flows throughthe stator windings, the stator windings produce a magnetic field vector.The magnetic field will lead to a rotor angle of rotation, making a pair of rotor and stator magnetic field direction of the magnetic field direction. When the stator rotating magnetic field vector from a different angle. Also as the rotor magnetic field to a point of view. An electrical pulse for each input, the motor rotation angle step. Its output and input of the angular displacement is proportional to the pulses, with pulse frequency proportional to speed. Power to change the order of winding,the electrical will be reversed. We can, therefore, control the pulse number, frequency and electrical power windings of each phase to control the order of rotation of stepper motor.Stepper motor types:Permanent magnet (PM). Magnetic generally two-phase stepper, torque and are smaller and generally stepping angle of 7.5 degrees or 15 degrees; put more wind for air-conditioning.Reactive(VR), the domestic general called BF, have a common three-phase reaction, step angle of 1.5 degrees; also have five-phase reaction. Noise, no torque has been set at a large number of out.Hybrid (HB), common two-phase hybrid, five-phase hybrid, three-phase hybrid, four-phase hybrid, two-phase can be common with the four-phase drive, five-phase three-phase must be used with their drives;Two-phase, four-phase hybrid step angle is 1.8 degrees more than a small size, great distance,and low noise;Five-phase hybrid stepping motor is generally 0.72, the motor step angle small, high resolution, but the complexity of drive circuits, wiring problems, such as the 5- phase system of 10 lines.Three-phase hybrid stepping motor step angle of 1.2 degrees, but according to the use of 1.8 degrees, the three-phase hybrid stepping motor has a two-phase mixed than the five-phase hybrid more pole will help electric folder symmetric angle, it can be more than two-phase, five-phase high accuracy, the error even smaller, run moresmoothly.Stepper motor to maintain torque: stepper motor power means no rotation, the stator locked rotor torque. It is a stepper motor, one of the most important parameters, usually in the low-speed stepper motor torque at the time of close to maintain the torque. As the stepper motor output torque increases with the speed of constant attenuation, the output power also increases with the speed of change,so as to maintain torque on the stepper motor to measure the parameters of one of the most important. For example, when people say that the stepper motor 2N.m, in the absence of special circumstances that means for maintaining the torque of the stepper motor 2N.m.Precision stepper motors:stepper motor step angle accuracy of 3-5%, not cumulative.Stepper motor to allow the minimum amount of surface 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.Start frequency of no-load: the stepper motor in case of no-load to the normal start of the pulse frequency, if the pulse frequency is higher than the value of motor does not start, possible to lose steps or blocking.In the case of the load, start frequency should be lower. If you want to achieve high-speed rotation motor, pulse frequency should be to accelerate the process, that is, the lower frequency to start, and then rose to a certain acceleration of the desired frequency (motor speed from low rise to high-speed).Step angle:that is to send a pulse,the electrical angle corresponding to rotation.Torque positioning: positioning torque stepper motor does not refer to the case of electricity,locked rotor torque stator.Operating frequency:step-by-step stepper motor can run without losing thehighest frequency.Subdivision Drive: stepper motor drives the main aim is to weaken or eliminate low-frequency vibration of the stepper motor to improve the accuracy of the motor running. Reduce noise. If the step angle is 1.8 °(full step) the two-phase hybrid stepping motor, if the breakdown of the breakdown of the number of drives for the 8, then the operation of the electrical pulse for each resolution of 0.072 °, the precision of motor can reach or close to 0.225 °, also depends on the breakdown of the breakdown of the drive current control accuracy and other factors, the breakdown of the number of the more difficult the greater the precision of control.How to determine the stepper motor driver DC power supply:A.Determination of the voltage: Hybrid stepping motor driver power supply voltage is generally a wide range (such as the IM483 supply voltage of 12 ~ 48VDC), the supply voltage is usually based on the work of the motor speed and response to the request to choose.If the motor operating speed higher or faster response to the request, then the voltage value is high, but note that the ripple voltage can not exceed the maximum input voltage of the drive,or it may damage the drive.B.Determination of CurrentPower supply current is generally based on the output phase current drive I to determine. If a linear power supply, power supply current is generally preferable 1.1 to 1.3 times the I; if we adopt the switching power supply, power supply current is generally preferable to I,1.5to 2.0 times.The main characteristics of stepping motor:1. A stepper motor drive can be added operate pulse drive signal must be no pulse when the stepper motor at rest, such as If adding the appropriate pulse signal, it will to a certain angle (called the step angle) rotation. Rotation speed and pulse frequency is proportional to.2.permanent magnet step angle stepper motor version is 7.5 degrees, 360 degrees around, takes48 pulses to complete.3.stepper motor has instant start and rapid cessation of superior characteristics. Change the order of the pulse4.you can easily change the direction of rotation.Therefore, the current printers, plotters, robotics, and so devices are the core of the stepper motor as the driving force.Stepper motors have the following benefits: (1)Low cost (2)Ruggedness (3)Simplicity in construction (4)High reliability(5)No maintenance(6)Wide acceptance(7)No tweaking to stabilize (8)No feedback components are neededThey work in just about any environment Inherently more failsafe than servo motors. There isvirtually no conceivable failure within the stepper drive module that could cause the motor to run away. Stepper motors are simple to drive and control in an open-loop configuration. They only require four leads. They provide excellent torque at low speeds, up to 5 times the continuous torque of a brush motor of the same frame size or double the torque of the equivalent brushless motor. This often eliminates the need for a gearbox. A stepper-driven-system is inherently stiff, with known limits to the dynamic position error.Stepper Motor Disadvantages:Stepper motors have the following disadvantages:1.Resonance effects and relatively long settling times.1.Rough performance at low speed unless a microstep drive is used.2.Liability to undetected position loss as a result of operating open-loop .4.They consume current regardless of load conditions and therefore tend to run hot5.Losses at speed are relatively high and can cause excessive heating, and they are frequently noisy (especially at high speeds).1.They can exhibit lag-lead oscillation, which is difficult to damp.There is a limit to their available size, and positioning accuracy relies on the mechanics(e.g., ballscrew accuracy).Many of these drawbacks can be overcome by the use of a closed-loop control scheme.外文资料翻译译文步进电机应用和控制步进电机是将电脉冲转换成角位移的执行机构。
单片机步进电机应用和控制大学毕业论文英文文献翻译及原文
毕业设计(论文)外文文献翻译文献、资料中文题目:单片机步进电机应用和控制文献、资料英文题目:文献、资料来源:文献、资料发表(出版)日期:院(部):专业:班级:姓名:学号:指导教师:翻译日期: 2017.02.14单片机控制步进电机外文原文Stepping motor application and control stepper motor is an electrical pulse will be converted into angular displacement of the implementing agencies. Put it in simple language-speaking: When the stepper drive pulse signal to a receiver, it drives stepper motor rotation direction by setting a fixed point of view (and the step angle). You can control the number of pulses to control the amount of angular displacement, so as to achieve the purpose of accurate positioning; At the same time, you can by controlling the pulse frequency to control the motor rotation speed and acceleration, so as to achieve the purpose of speed.Stepper motor directly from the AC-DC power supply, and must use special equipment - stepper motor drive. Stepper motor drive system performance, in addition to their own performance with the motor on the outside, but also to a large extent depend on the drive is good or bad. A typical stepper motor drive system is operated by the stepper motor controller, stepper motor drives and stepper motor body is composed of three parts. Stepper motor controller stepper pulse and direction signal, each made of a pulse, stepper motor-driven stepper motor drives a rotor rotating step angle, that is, step-by-step further. High or low speed stepper motor, or speed, or deceleration, start or stop pulses are entirely dependent on whether the level or frequency. Decide the direction of the signal controller stepper motor clockwise or counterclockwise rotation. Typically, the stepper motor drive circuit from the logic control, power driver circuit, protection circuit and power components. Stepper motor drive controller, once received from the direction of the signal and step pulse, the control circuit on a pre-determined way of the electrical power-phase stepper motor excitation windings of the conduction or cut-off signal. Control circuit output signal power is low, can not provide the necessary stepping motor output power, the need for power amplifier, which is stepper motor driven power drive part. Power stepper motor drive circuit to control the input current winding to form a space for rotating magnetic field excitation, the rotor-driven movement. Protection circuit in the event of shortcircuit, overload, overheating, such as failure to stop the rapid drive and motor.Motor is usually for the permanent magnet rotor, when the current flows through the stator windings, the stator windings produce a magnetic field vector. The magnetic field will lead to a rotor angle of rotation, making a pair of rotor and stator magnetic field direction of the magnetic field direction. When the stator rotating magnetic field vector from a different angle. Also as the rotor magnetic field to a point of view. An electrical pulse for each input, the motor rotation angle step. Its output and input of the angular displacement is proportional to the pulses, with pulse frequency proportional to speed. Power to change the order of winding, the electrical will be reversed. We can, therefore, control the pulse number, frequency and electrical power windings of each phase to control the order of rotation of stepper motor.Stepper motor types:Permanent magnet (PM). Magnetic generally two-phase stepper, torque and are smaller and generally stepping angle of 7.5 degrees or 15 degrees; put more wind for air-conditioning.Reactive (VR), the domestic general called BF, have a common three-phase reaction, step angle of 1.5 degrees; also have five-phase reaction. Noise, no torque has been set at a large number of out.Hybrid (HB), common two-phase hybrid, five-phase hybrid, three-phase hybrid, four-phase hybrid, two-phase can be common with the four-phase drive, five-phase three-phase must be used with their drives;Two-phase, four-phase hybrid step angle is 1.8 degrees more than a small size, great distance, and low noise;Five-phase hybrid stepping motor is generally 0.72, the motor step angle small, high resolution, but the complexity of drive circuits, wiring problems, such as the 5-phase system of 10 lines.Three-phase hybrid stepping motor step angle of 1.2 degrees, but according to the use of 1.8 degrees, the three-phase hybrid stepping motor has a two-phase mixed than the five-phase hybrid more pole will help electric folder symmetric angle, it can be more than two-phase, five-phase high accuracy, the error even smaller, run moresmoothly.Stepper motor to maintain torque: stepper motor power means no rotation, the stator locked rotor torque. It is a stepper motor, one of the most important parameters, usually in the low-speed stepper motor torque at the time of close to maintain the torque. As the stepper motor output torque increases with the speed of constant attenuation, the output power also increases with the speed of change, so as to maintain torque on the stepper motor to measure the parameters of one of the most important. For example, when people say that the stepper motor 2N.m, in the absence of special circumstances that means for maintaining the torque of the stepper motor 2N.m.Precision stepper motors: stepper motor step angle accuracy of 3-5%, not cumulative.Stepper motor to allow the minimum amount of surface 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.Start frequency of no-load: the stepper motor in case of no-load to the normal start of the pulse frequency, if the pulse frequency is higher than the value of motor does not start, possible to lose steps or blocking. In the case of the load, start frequency should be lower. If you want to achieve high-speed rotation motor, pulse frequency should be to accelerate the process, that is, the lower frequency to start, and then rose to a certain acceleration of the desired frequency (motor speed from low rise to high-speed).Step angle: that is to send a pulse, the electrical angle corresponding to rotation.Torque positioning: positioning torque stepper motor does not refer to the case of electricity, locked rotor torque stator.Operating frequency: step-by-step stepper motor can run without losing thehighest frequency.Subdivision Drive: stepper motor drives the main aim is to weaken or eliminate low-frequency vibration of the stepper motor to improve the accuracy of the motor running. Reduce noise. If the step angle is 1.8 °(full step) the two-phase hybrid stepping motor, if the breakdown of the breakdown of the number of drives for the 8, then the operation of the electrical pulse for each resolution of 0.072 °, the precision of motor can reach or close to 0.225 °, also depends on the breakdown of the breakdown of the drive current control accuracy and other factors, the breakdown of the number of the more difficult the greater the precision of control.How to determine the stepper motor driver DC power supply:A. Determination of the voltage:Hybrid stepping motor driver power supply voltage is generally a wide range (such as the IM483 supply voltage of 12 ~ 48VDC), the supply voltage is usually based on the work of the motor speed and response to the request to choose. If the motor operating speed higher or faster response to the request, then the voltage value is high, but note that the ripple voltage can not exceed the maximum input voltage of the drive, or it may damage the drive.B. Determination of CurrentPower supply current is generally based on the output phase current drive I to determine. If a linear power supply, power supply current is generally preferable 1.1 to 1.3 times the I; if we adopt the switching power supply, power supply current is generally preferable to I, 1.5 to 2.0 times.The main characteristics of stepping motor:1. A stepper motor drive can be added operate pulse drive signal must be no pulse when the stepper motor at rest, such as If adding the appropriate pulse signal, it will to a certain angle (called the step angle) rotation. Rotation speed and pulse frequency is proportional to.2. permanent magnet step angle stepper motor version is 7.5 degrees, 360 degrees around, takes 48 pulses to complete.3. stepper motor has instant start and rapid cessation of superior characteristics. Change the order of the pulse4.you can easily change the direction of rotation.Therefore, the current printers, plotters, robotics, and so devices are the core of the stepper motor as the driving force.Stepper motors have the following benefits: (1)Low cost (2)Ruggedness (3)Simplicity in construction (4)High reliability (5)No maintenance (6)Wide acceptance(7)No tweaking to stabilize (8)No feedback components are needed They work in just about any environment Inherently more failsafe than servo motors. There isvirtually no conceivable failure within the stepper drive module that could cause the motor to run away. Stepper motors are simple to drive and control in an open-loop configuration. They only require four leads. They provide excellent torque at low speeds, up to 5 times the continuous torque of a brush motor of the same frame size or double the torque of the equivalent brushless motor. This often eliminates the need for a gearbox. A stepper-driven-system is inherently stiff, with known limits to the dynamic position error.Stepper Motor Disadvantages:Stepper motors have the following disadvantages:1. Resonance effects and relatively long settling times .2.Rough performance at low speed unless a microstep drive is used .3.Liability to undetected position loss as a result of operating open-loop .4. They consume current regardless of load conditions and therefore tend to run hot5. Losses at speed are relatively high and can cause excessive heating, and they are frequently noisy (especially at high speeds).6.They can exhibit lag-lead oscillation, which is difficult to damp.There is a limit to their available size, and positioning accuracy relies on the mechanics (e.g., ballscrew accuracy).Many of these drawbacks can be overcome by the use of a closed-loop control scheme.外文资料翻译译文步进电机应用和控制步进电机是将电脉冲转换成角位移的执行机构。
步进电机 英文翻译
郑州航空工业管理学院英文翻译2014 届电气工程及其自动化专业班级姓名学号指导教师职称二О一四年 2 月22 日Stepper motorStepper motor is the electrical pulse signal into angular displacement or linear displacement of an open loop stepper motor control element pieces . In the case of non- overloading , motor speed , stopped position depends only on the number of pulse frequency and pulse signals , which are not affected by changes in load , when stepper drive receives a pulse signal , it will drive a stepper motor the rotational direction is set to a fixed angle , referred to as " step angle ", which is fixed to the rotational angle of the step by step operation . The number of pulses can be controlled by controlling the amount of angular displacement , so as to achieve accurate positioning ; while the pulse frequency can be controlled by controlling the motor rotation speed and acceleration to achieve speed control purposes .1. basic introductionStepper motor is an induction motor, it works by using an electronic circuit .The DC power into power -sharing , multi-phase timing control current, this current is powered stepper motor , stepper motor to work properly, the stepper motor drive is powered -sharing , multi-phase timing controller .Although the stepper motor has been widely used, but the stepper motor does not like an ordinary DC motors, AC motors for use in routine under . It must be by a two- ring pulse signal , power driver circuit composed of the control system can be used. So make good use of a stepper motor , but not easy, it involves a lot of expertise in mechanical ,electrical , electronics and computers.Stepper motors as actuators , is one of the key products of mechatronics , widely used in a variety of automated control systems. With the development of microelectronics and computer technology, the growing demand for stepper motor , has applications in various fields of national economy .Stepper motor is an electrical pulse into the angular displacement of the actuator. Plainly speaking : When the stepper drive receives a pulse signal , it will drive a stepper motor to set the direction of rotation of a fixed angle ( ie, step angle ) . The number of pulses can be controlled by controlling the amount of angular displacement , so as to achieve accurate positioning ; while the pulse frequency can be controlled by controlling the motor rotation speed and acceleration to achieve speed control purposes .2. major categoriesThere are three main types of stepper motors in the structure : Reaction (Variable Reluctance, VR), permanent magnet (Permanent Magnet, PM) and hybrid (Hybrid Stepping, HS).Reaction: the stator windings , the rotor soft magnetic material. Simple structure, low cost , small step angle up to 1.2 °, but poor dynamic performance , low efficiency, heat a large , difficult to guarantee reliability .Permanent magnet : permanent magnet stepper motors with permanent magnet rotor material, the number of poles of the rotor and the stator of the same number of poles . Which is characterized by good dynamicperformance, output torque, this motor but poor accuracy , a large step angle (typically 7.5 ° or 15 °).Hybrid : a combination of hybrid stepping motors and permanent magnet reactive advantage of its multi-phase windings on the stator , the rotor permanent magnet material , the rotor and the stator teeth are a number of small steps to improve the accuracy of the moment . It features an output torque, good dynamic performance, step angle is small, but the structure is complex, the cost is relatively high.Press the stator windings to points , a total of two-phase , three-phase and five equal series. Most popular is the two-phase hybrid stepping motor , accounting for more than 97 % market share , the reason is the high cost , coupled with good results after the breakdown of the drive. This kind of basic step angle of the motor 1.8 °/ step , half step back coupled with the drive to reduce the step angle of 0.9 °, coupled with sub-drive after its step angle can be broken up to 256 -fold (0.007 °/ micro step ) . Due to friction and manufacturing precision and other reasons , the actual control accuracy is slightly lower . Same stepper motors can be equipped with different segments of the drive to change the precision and effectiveness.3. selection methodStepper motor and drive selection methods :Determine how much torque is required : static torque stepper motor is to choose one of the main parameters. Load is large, requires the use of high torque motor. Indicators big moment , the motor appearance is also large.Determine motor speed : high speed requirements , should be selected phase current is larger , smaller inductor motors to increase power input. And select the drive when using higher supply voltages.Select motor installation specifications : as 57,86,110 , the main requirements for the moment .Determine the precision positioning requirements and vibration aspects of the case : to determine whether the required segments, the number of segments required .According to the motor current , supply voltage breakdown and select the drive .4. Basic PrinciplesWorksThe rotor is a permanent magnet motor typically , when a current flows through the stator windings , the stator winding generates a magnetic field vector . The rotating magnetic field to drive the rotor at an angle such that the magnetic field of the stator is consistent with a direction of the magnetic field of the rotor. When the stator magnetic field vector rotation angle. As the rotors turn a field angle . Each input an electrical pulse , the motor rotation angle forward. The number of pulses proportional to the angular displacement of the output and its input , the pulse frequency is proportional to the rotational speed . Change the order of the winding is energized , the motor will reverse. Therefore, the number of pulses can be used to control power-on sequence , frequency and motor windings to control each phase stepper motor rotation .Fever principleUsually see all kinds of motors , are all inside the core and windings . Windings resistance , power will produce loss , the loss is proportional to the square of the size of the resistance and current , and this is what we often say that the copper losses , if the current is not a standard DC or sine wave , but also produce harmonic losses ; core has hysteresis eddy current effect , in the alternating magnetic field will produce losses , its size and materials , current, frequency , voltage dependent , called iron loss. Copper and iron losses are manifested in the form of heat , thus affecting the efficiency of the motor . Stepper motors are generally pursue positioning accuracy and torque output , efficiency is relatively low, the current is generally relatively large, and the high harmonic components , the frequency of the alternating current with the speed of change, thus stepping motor widespread fever cases and situations than the general severe AC motor .5. major tectonicStepping motor is also called a stepper , which uses the principle of electromagnetic , mechanical energy is converted to electrical energy , People as early as the 1920s began to use this motor . As embedded systems ( such as printers, disk drives , toys, wipers, pager vibration , mechanical arm and video recorders , etc. ) of the increasingly popular use of the stepper motor also began surge. Whether in industrial, military , medical, automotive or entertainment industry , as long as a piece of the object needs to be moved from one location to another , the stepper motor will certainly come in handy. Stepper motors have many shapes and sizes, but regardless of how the shape and size , they can be classified into two categories : a variable reluctance stepper motors and permanent magnetstepper motors.A stepper motor is wound on the motor fixing part - the stator coils driven alveolar . Typically , a ring-shaped metal wire called a solenoid winding , and in the motor , the teeth around the winding wire is called the coil or phase .6. index termsStatic index terms1, number of phases : produce different on pole N, S magnetic excitation coil pairs. Common m said .2, Beats: cyclical changes in the magnetic field required to complete a number of pulses or conductive state with n, or refer to the motor turned a pitch angle required number of pulses to four-phase motor, for example , there are four ways with four -run shot that AB-BC-CD-DA-AB, four-phase eight-shot operation That way A-AB-B-BC-C-CD-D-DA-A. 3, step angle : corresponds to a pulse signal , the angular displacement of the rotor turn is repre sented by θ. θ = 360 degrees / ( number of rotor teeth * run shot ) to the conventional two , four-phase , the rotor teeth 50 teeth motor, for example . Four beats running step angle is θ = 360 degrees / ( 50 * 4 ) = 1.8 degrees ( commonly known as the full step ) , eight-shot operation step angle of θ = 360 degrees / ( 50 * 8 ) = 0.9 degrees ( commonly known as half-step ) .4, the detent torque : motor is not energized in the state itself locked rotor torque ( harmonics and mechanical error by the magnetic field caused by the tooth ) .5, static torque : motor at rated static electricity effect, the motor doesnot rotates when the motor shaft locking torque. This moment is a measure of the volume of the standard motor , regardless of the driving voltage and driving power supply. Although static torque is proportional to the electromagnetic excitation ampere-turns , and set the air gap between the rotor teeth related, but over the use of the air gap decreases , increasing the excitation ampere-turns to increase the static torque is not desirable, this will cause motor heating and mechanical noise.Dynamic Indicators term1,step angle accuracy: stepper motor turned every error between the actual value and the theoretical value of a step angle . Expressed as a percentage : error / step angle * 100 %. Different running different beats its value , when the four -run shot in the 5% ,eight shot should run less than 15 %.2, step : the number of steps the motor running operation does not mean that the theoretical number of steps . Called out of step .3, the offset angle: rotor stator teeth tooth axis shift axis angle , the motor is running there must be offset angle , angle error generated by the imbalance , driven by subdivision can not be solved .4, he maximum no-load starting frequency : motor in the form of a drive voltage and rated current, in the case without the load, the maximum frequency can directly start .5, the operating frequency of the maximum load : the motor in the form of a drive voltage and rated current, the maximum speed of the motor with no load frequency .6, running torque characteristics : Measured motor running undercertain test conditions the output torque versus frequency curve is called the running torque-frequency characteristic , which is the motor of many dynamic curve of the most important , but also the fundamental basis for the motor selection.Other features include inertia frequency characteristics, starting frequency characteristics. Once the motor is selected, the static torque of the motor is determined , and dynamic moment is not the case , the dynamic torque motor depends on the average current ( rather than static current ) motor is running , the average current , the greater the motor output torque that the motor frequency characteristics of the harder . For the average current, the drive voltage to maximize the use of small high-current inductor motor .7, the resonance point of the motor : stepper motor has a fixed resonance region , two , four-phase Induction resonance zone is generally between 180-250pps ( step angle of 1.8 degrees ) , or about 400pps ( step angle 0.9 degrees ) , the higher the motor drive voltage , motor current increases, the lighter the load , motor size smaller, the upward shift resonance region , and vice versa , so that the motor output torque is large , and the entire system without losing step noise reduction , general working point should shift more resonance region .8, motor reversing control : the timing of when the motor windings are energized for the forward , the timing is energized when AB-BC-CD-DA or () DA-CD-BC-AB or ( ) when inverted.7. features characteristicThe main features1, the general accuracy of the stepper motor step angle of 3-5 % , and does not accumulate.2, the appearance of the stepper motor maximum temperature allowed . First, make a stepper motor temperature magnetic motor demagnetization ,Resulting in the loss of torque down even further , so the maximum temperature of the motor should be allowed depending on the appearance of magnetic motor demagnetization points ; generally speaking, magnetic demagnetization points above 130 degrees Celsius , and some even as high as 200 degrees Celsius above , so the stepper motor surface temperature at 80-90 degrees Celsius completely normal .3, stepper motor torque will increase with the speed of decline .When the stepping motor rotates , the inductance of the motor windings of each phase will form a counter electromotive force ; the higher the frequency, the greater the back EMF . In its role, the motor with frequency ( or speed ) increases the phase current is reduced , resulting in decreased torque .4, the stepper motor can operate normally at low , but if more than a certain speed will not start , accompanied by howling.Stepper motor has a technical parameter : load starting frequency , ie stepper motor under no-load conditions to start the normal pulse frequency , if the pulse frequency is higher than this value, the motor does not start properly , you may lose steps or stall . Under a load , the starting frequency should be lower . If you want the motor to achieve high-speed rotation , the pulse frequency should speed up the process ,which starts at lower frequencies , and then rise to the hope that at a certain acceleration frequency ( motor speed rise from low speed ) . Stepper motor with its remarkable features in the era of digital manufacturing plays a significant purpose. Along with improving the different development of digital technology and the technology itself, stepper motor , stepper motors will be applied in more fields .Key FeaturesA stepping motor can be operated must be added before the drive , the drive signal is a pulse signal to be no pulse when the stepping motor is stationary, if the addition of a suitable pulse signal will at a certain angle ( called a step angle ) is rotated. Rotational speed and the pulse frequency is proportional to .2, phase stepper motor step angle of 7.5 degrees, 360 degrees around , you need to complete the 48 pulses .3, stepper motor with instant start and stop the rapid superior characteristics .4, change the order of the pulse , you can easily change the direction of rotation .Therefore , printers , plotters , robotics and other equipment to the stepper motor driven core .8. speed methodStepper motor pulse signal is converted to angular displacement or linear displacement .First, the overload is good. Its speed independent of load size , unlikeordinary motor when the load increase rate decline occurs when using the stepper motor speed and position , there are stringent requirements.The second is easy to control. Stepper motors are "steps" as a unit rotation , digital features more obvious .Third, the whole structure is simple . Traditional mechanical speed and position control structure is complicated , difficult to adjust after using stepper motors , which makes it simple and compact structure . Motor rotation speed is converted into a voltage , and passed as a feedback signal to the input terminal . Tacho is an auxiliary motor , the motor is installed at the end of the ordinary speed DC motor , the voltage generated by the motor speed feedback to the DC power supply, DC motor speed control to achieve the purpose .9. function module designThis module can be divided into the following three parts:· SCM system : control of stepper motors ;· Peripheral circuits : PIC microcontroller interface circuit and stepper motors ;· PIC procedure : Write SCM stepper electric power machine interface program to achieve output of the triangular wave signal.( 1 ) stepper motor and microcontroller interface .SCM is the excellent performance of the control processor, stepper motor control , interface components must have the following features.① voltage isolation .SCM work at 5V, while the stepper motor is working in dozens of V, or even higher. Once the voltage to the microcontroller series stepper motor , it will damage the microcontroller ; signals would interfere with chip stepper motor , the system may also lead to errors in the work , so the interface device must have isolation .② messaging functions.Interface components should be able to pass information to the microcontroller stepper motor control circuit generates control information needed work , corresponding to different ways of working, interface components should be able to produce a corresponding job control waveform.③ produce different frequencies required .To the stepping motor at different speeds to suit different purposes , interface components should produce different operating frequencies . ( 2 ) V oltage Isolation interface.Isolation voltage isolation interface dedicated to the low-pressure part of the microcontroller and the stepper motor drive circuit high-voltage part , to ensure that they work properly.V oltage pulse transformer isolation interface or optical isolator is basically the use of optical isolators. Microcontroller output signal can be sent directly to the TTL gate or base of the transistor , and then driven by the transistor optocoupler devices emitting diodes.Light -emitting diodes on the opto-coupler devices inside the photodiode , converted into electrical signals , go drive a stepper motor power amplifier circuit , current amplification interface is a stepper motoramplifier circuit preamplifier circuit . Its role is to optical isolator output signal current amplification in order to provide enough power amplifier circuit drive current .( 3 ) Work interface and frequency generator .MCU controlled stepper motor requires the input and output interfaces for controlling stepper motors using three I / 0 lines, this time, the microcontroller I / O port RA0, RAI, RA2 control three-phase stepping motor .10. advantages and defectsAdvantage1, the angle of rotation of the motor is proportional to the number of pulses ;2, when the motor is stopped with a maximum torque ( when winding excitation time ) ;3, the accuracy of each step in the three percent to five percent , but the error will not accumulate to the next step and thus a better position accuracy and repeatability movement ;4, excellent response from the stop and reverse ;5, since there is no brush , high reliability, and therefore the life of the motor depends only on bearing life ;6, only the response of the motor is determined by the digital input pulse , which can be open-loop control, which makes the structure of the motor can be relatively simple and cost control ;7, only the load can be connected directly to a very low speed synchronous rotation on the shaft of the motor ;8, since the speed is proportional to the pulse frequency , and thus a relatively wide speed range.Defect1, if not properly controlled prone resonance ;2, the high speed operation is difficult ;3, it is difficult to obtain a large torque ;4, there is no advantage, low energy efficiency in terms of volume and weight ;5, more than the load will destroy the synchronization , will be issued when the high speed vibration and noise .11. drive methodStepper motors can be connected directly to the power frequency AC or DC power source to work , but must use a dedicated stepper motor driver , which occurs by the pulse control unit , power drive unit , the protection unit and so on. Stepper motor drive unit with direct coupling , can also be interpreted as a stepper motor controller microprocessor power connector.12. drive requirements1, can provide rapid current rise and fall times ,Current waveform as close as possible to make a rectangle .With a cut-off period for the release of the current flow loop to reducethe back electromotive force at both ends of the windings and accelerate the current decay .2, has a high rhyme power and efficiency.Stepper motor driver , which is a pulse signal into the control system of the angular displacement of the stepper motor , or : a control signal for each pulse issued by the stepper motor drive of a step angle of rotation . That frequency is proportional to the speed of the stepper motor pulse signal. So to control the frequency pulse signal , the speed of the motor can be accurately ; controlled stepper pulse number , you can pinpoint the motor . There are a lot of stepper motor drive , power requirements should be based on the actual reasonable choice drive.13. Major ApplicationsSelect the stepper motorThere are step angle stepping motor ( related to the number of phases ) , static torque , and the current composition of the three elements .Once identified three elements , the stepper motor model has determined.1, step angle selectionStep motor angle accuracy depends on the load requirements , the minimum resolution of the load ( equivalent ) conversion to the motor shaft , the number of angles ( including gear ) for each equivalent motor should go. Step motor angle should be equal to or less than this angle. Step angle stepping motor on the market are generally 0.36 °/ 0.72 °( five-phase motors ) , 0.9 degrees / 1.8 degrees ( two , four-phase motor ) , 1.5 degrees / 3 degrees ( three-phase motors ) and so on.2, static moment of choiceDynamic torque stepper motor is difficult to determine all of a sudden , we tend to first determine the static torque of the motor. The choice is based on static torque load on the motor work, and the inertia of the load and the load can be divided into two kinds of friction load . Single inertia load and a single load is not present in friction . When direct start ( generally low ) when the two loads are to be considered , the main consideration inertial load during acceleration start, constant run into just consider friction loads. Under normal circumstances, the static torque should be 2-3 times the load of friction is good, static torque Once selected, the machine base and be able to determine the length of the motor down ( geometry ) .3, the current selectionLike static torque motors , due to the different current parameters , their operating characteristics vary greatly, can be based on torque-frequency characteristic curve , determine the motor current . Application note points1, the stepper motor used in low-speed situations --- rpm less than 1000 rpm , ( 0.9 degrees 6666PPS), preferably using 1000-3000PPS (0.9 degrees ) between , can make it work here through deceleration devices, At this high electrical efficiency, low noise ;2, the stepper motor is best not to use the state of the whole step , whole step when the state of vibration ;3, due to historical reasons, only a nominal voltage of 12V 12V motors , the voltage value other than the motor drive voltage V value, drive selectdriving voltage according to ( suggestions : 57BYG DC 24V-36V, 86BYG DC 50V, 110BYG using higher than the DC 80V), of course, in addition to 12 volts 12V constant voltage driver can also use other external power supply, but to consider the temperature rise ;4, the moment of inertia of the load should choose a large frame size motors ;5, when compared with the high-speed motor or high inertia loads , generally do not start working speed , and the use of up- speed gradually , without losing a step motor , two noise can be reduced while improving the positioning accuracy is stopped ;6, high-precision, through mechanical reduction should improve motor speed , or high number of sub-drive to solve, 5 -phase motor can also be used , but the prices of its entire system more expensive , less manufacturer , which is eliminated argument is the layman ;7, the vibration motor in the region should not , should be resolved by changing the voltage , current, or add some damping ;8, motor 600PPS (0.9 degrees ) following work should be low current , high inductance , low voltage to drive ;9, after the first election should follow the principle of the drive motor option .步进电机步进电机是将电脉冲信号转变为角位移或线位移的开环控制元步进电机件。
外文翻译--步进电机运动控制系统设计
密级分类号编号成绩本科生毕业设计 (论文)外文翻译原文标题Stepper Motor Motion Control System Design 译文标题步进电机运动控制系统设计作者所在系别机械工程系作者所在专业机械设计制造及其自动化作者所在班级作者姓名作者学号指导教师姓名指导教师职称完成时间2012 年 2 月的个数严格成正比,在时间上与输入脉冲同步,因此只要控制输入脉冲的数量、频率及电动机绕组通电的相序,便可获得所需的转角、转速及转动方向。
在没有脉冲输入时,在绕组电源的激励下气隙磁场能使转子保持原有位置处于定位状态。
因此非常适合于单片机控制。
步进电机还具有快速启动、精确步进和定位等特点,因而在数控机床,绘图仪,打印机以及光学仪器中得到广泛的应用。
步进电动机已成为除直流电动机和交流电动机以外的第三类电动机。
传统电动机作为机电能量转换装置,在人类的生产和生活进入电气化过程中起着关键的作用。
步进电机可以作为一种控制用的特种电机,利用其没有积累误差(精度为100%)的特点,广泛应用于各种开环控制。
现在比较常用的步进电机包括反应式步进电机(VR)、永磁式步进电机(PM)、混合式步进电机(HB)和单相式步进电机等。
一步进电机的工作原理步进电机是一种用电脉冲进行控制 ,将电脉冲信号转换成相位移的电机 ,其机械位移和转速分别与输入电机绕组的脉冲个数和脉冲频率成正比 ,每一个脉冲信号可使步进电机旋转一个固定的角度.脉冲的数量决定了旋转的总角度 ,脉冲的频率决定了电机运转的速度.当步进驱动器接收到一个脉冲信号,它就驱动步进电机按设定的方向转动一个固定的角度(称为“步距角”),它的旋转是以固定的角度一步一步运行的。
可以通过控制脉冲个数来控制角位移量,从而达到准确定位的目的;同时可以通过控制脉冲频率来控制电机转动的速度和加速度,从而达到调速的目的。
二步进电机详细调速原理步进电机的调速一般是改变输入步进电机的脉冲的频率来实现步进电机的调速,因为步进电机每给一个脉冲就转动一个固定的角度,这样就可以通过控制步进电机的一个脉冲到下一个脉冲的时间间隔来改变脉冲的频率,延时的长短来具体控制步进角来改变电机的转速,从而实现步进电的调速。
电机 电子 运动控制 伺服系统 英语单词表
Motor 电机Supply提供Connector连接口Feedback反馈CAN (Controller Area Network)总线Brushless motor无刷电机Step motor步进电机Brushless 无刷Brush 刷子Phase相位Switch转换Sensor传感器Encoder编码器power supply电源供应器supply供应AC (Alternating Current)交流电DC (direct current)直流电input power输入功率input 输入outputs 输出current 电流voltage 电压Servo伺服Driver 驱动器Logic逻辑Vector矢量Control 控制Open 打开Closed 关闭Typical Applications 典型应用Motion Control Libraries运动控制库Fully digital intelligent全数字智能graphical development environment 图形开发环境Features 特征Execute 实行Complex 复杂的Powerful强大的Suitable适用、相配的Compatible兼容的Programmable可编程的Analog模拟的Digital 数字的User manual 使用手册Family家庭New Member 新成员Dynamic torque动态转矩OPEN LOOP开环控制PPS (pulse per second)每秒脉冲数Power stage 功率电路Uni-plar单极Bi-polar双极型PM (Permanent Magnet)永久磁铁Sleeve metal 金属滑动轴承Multi-Stack 串联多级FDD (Floppy Disk Drive )软盘驱动器RM (Ring-permanent-Magnet)圆环形磁铁Sawyer 索耶Outer rotor motor 或inverted motor外转子电机Pull-out-torque 失步转矩Pull-in-torque牵入转矩Over-shoot超越角Under-shoot 返回角Setting time 稳定时间Sleeve metal滑动轴承Pre-load 预紧力Chopper 恒电流斩波器Step 步Slow up 慢下来Speed up 加速Speed速度Position位置Error误差Cogging齿槽转矩Hall sensor霍尔传感器Continuous Stall Current 持续堵转电流Maximum Mechanical Speed最大的电机转速Continuous Current额定电流Peak Current峰值电流Tuning调整Loop 环Connector Type连接类型Mating结合CONTROL SUPPLY控制电源/输入电源Table表格Protection 保护Male 男的公头Female 女的母头Provides 提供. Pin针Pinout 引出线Motion Control 运动控制Windows 窗口wall-mounted 固定在墙上absence 失去acceleration 加速accept 接受access 存取accomplish 完成,达到accuracy 准确,精确acid 酸性,酸的action 动作Active power 有功功率address 地址adequate 适当的,充分的adjust 调整,校正after 以后air 风,空气Alarm 报警Ambient 周围的,环境的Ambient temp 环境温度ammeter 电流表,安培计Ampere 安培amplifier 放大器Analog 模拟Analog input 模拟输入Angle 角度Anion 阴离子Anode 阳极,正极anticipate 预期,期望Application program 应用程序Arc 电弧,弧光Area 面积,区域Ash 灰烬,废墟assemble 安装,组装Attempt 企图Automatic AUTO 自动Auxiliary AUX 辅助的Available 有效的,可用的Avoid 避免,回避Avometer 万用表,安伏欧表计Axial 轴向的Axis 轴,轴线Axis disp protection 轴向位移,保护Axle 轴,车轴,心捧Back 背后,反向的Back up 支持,备用Back ward 向后Baffle 隔板Balance 平衡Ball 球Bar 巴,条杆base 基础、根据Base load 基本负荷Base mode 基本方式Battery 电池before 在…之前bell 铃Belt 带,皮带Black 黑色Blow 吹Blow down 排污blue 蓝色bore 孔,腔Boot strap 模拟线路,辅助程序bottom 底部brash 脆性,易脆的bracket 支架,托架,括号breadth 宽度break 断开,断路brush 电刷,刷子bucket 斗,吊斗built 建立bump 碰,撞击busbar 母线button 按钮cabinet 柜cable 电缆calculator 计算器caliber 管径、尺寸、大小calorie 卡caloric 热的、热量Caloric value 发热量、热值calorific 发热的、热量的Calorific efficiency 热效率cancel 取消、省略capacitance CAPAC 电容Capacitive reactance 容抗capacity 容量、出力、能量card (电子)板、卡cascade CAS 串级Case pipe 套管casine 壳、箱casual 偶然的、临时、不规则的cathode 阴板、负极Center 中心Chamber 办公室、会议室Change 改变Charge 负荷、充电、加注Check 检查Chest 室Chief 主要的、首长、首领Circuit 电路Circuit diagram 电路图Clamp 夹具、钳Clarification 澄清Class 类、等级、程度Clean 清洁的、纯净的Cleanse 净化、洗净、消毒Clear 清除Clockwise 顺时针、右旋的Close 关闭Closed-loop 闭环Coal 煤Coal dust 煤粉Coil 线圈Cold 冷air 大气风Collect 收集Colour 颜色Combin 合并、联合Combustion 燃烧Command 命令、指挥Commission 使投入、使投产Common 共同的、普通的Compensation 补偿Complexity 复杂Complete 完成Component 元件Compress 压缩Computer 计算机. Condensive reactance 容抗Condition 条件、状况Conduct 传导Conductivity 导电率Conference 会议、商讨、谈判Configure 组态Connection 联接Console 控制台Consult 商量、咨询、参考Consumption 消费、消耗Constant 恒定的Contact 触点Contactor 接触器、触头Contact to earth 接地、触地、碰地Content 目录Continuous 连续的Contract 合同Control CNTR/CNTPL 控制Control loop 控制环Controller 控制器Convection 对流Convertor 运输机、传输机. Cool 冷的Cooling 冷却Coordinate COORD 协调Copy 拷贝Core 铁心、核心、磁心Corner 角落Correction 修正、改正Corrosion 腐蚀Cost 价格、成本、费用Crane 起重机Critical 临界的Critical speed 临界速度Cube 立方(体)Curdle 凝固Current 电流、当前Cursor 光标Curve 曲线Custom 习惯、海关Cutter 切削工具Cyanic 青色、深蓝色Cycle 循环、周期、周波Cymometer 频率表. Damage 损坏、破坏Danger 危险、危险物Dank 潮湿Danger zone 危险区Data 数据Data base 数据库Date 日期Data pool 数据库Dead band 死区Decimeter 分米Deep 深度、深的、深Degree 度、等级Delay 延迟Delay time 延时Delete 删除Deposit 沉积结垢Description 说明、描述Destination 目标、目的地Detail 细节Detect 发现、检定Deviate 偏离、偏差Device 设备、仪器. Diagnosis 诊断Diagram 图形、图表Diameter 直径Diaphragm 膜片、隔板Dielectric 介质、绝缘的Difference 差异、差别、差额Diff press 差压Digital 数字的Digital electric hydraulic 电调Digital input/output 数字量输入/输出Dioxde 二氧化碳Direct current DC 直流(电)Disassembly 拆卸Disaster 事故、故障Disaster shutdown 事故停机Discharge 排除、放电、卸载Disk 磁盘Dispatcher 调度员Disk 磁盘Displacement 位移Display 显示、列屏Distance 距离. Disturbance 扰动Divided by 除以Design 设计、发明Division 分界、部门Division wall 分割屏Documentation 文件Door 门Dowel pin 定位销Down pipe 下降管Download 下载Downtime 停机时间Dozer 推土机Draft 通风、草图Drain pump 疏水泵Drain tank 疏水箱Drawing 图样、牵引Drill 钻孔、钻头、钻床Drive 驱动、强迫Drop 站Drum 汽包Dry 干、干燥Dust 灰尘. Duty 责任Dynamic 动态的Dynamometer 功率表Earth 大地Earth fault 接地故障Earth connector 接地线、接地Earth lead 接地线、接地Eccentricity 偏心、扰度Edit 编辑Efficiency 效率Ejection 射出Ejector 抽气器Electric 电的Elbow 弯管、弯头Electrical 电的、电气的Electrical machine 电机Electrode 电极Electronic 电子的、电子学的Electrostatic 静电的Element 元件、零件、单元Ellipse 椭圆Emergency decree 安规. Emerg off 事故停/关闭Employee 雇员Empty 排空Enclosure 外壳、包围End 末端、终结End cover 端盖Energize 激励、加电Energy 能、能量Energy meter 电度表Energy source 能源Enter 开始、使进入Entry 输入Equipment 设备Erase 删除Error 错误Event 事件Excess 超过、过度Exit 出口Expenditure 费用Expert 专家、能手Explosion 爆炸External 外部的、表面的. Extinguisher 灭火器Extend 扩展、延伸Exteral 外部的、表面的Factor 因素、因数Fahrenheit 华式温标Failure FAIL 失败FALSE 假的、错误的Fan 风扇、风机Fault 故障Features 特点Feed 馈、供给Feedback 反馈Feed forward 前馈Feed water 给水Fiber optic 光纤Field 磁场、现场Figure 数字、图案File 文件Final 最后的Fire 燃烧、火焰Fire-proof 耐火的、防火的Fire-fight 灭火. Fireproof 防火的、阻燃的First stage 第一级、首级Flame 火焰Flank 侧翼、侧面Flash lamp 闪光灯Flash light 闪光Flasher 闪光装置Flexible 灵活的、柔性的Flow 流量、流动Flue 烟道Format 形式、格式Follow 跟随Forbid 禁止Force 强制Forward 向前Free end 自由端Frequency 频率From 从、来自Front 前面的Fuel 燃料Fully 充分的、完全的Function 功能. Fuse 保险丝、熔断器Fuse holder 保险盒Gate 闸门Gateway 入口、途径Gauge 仪表、标准Gear 齿轮Generate 引起、产生Generator 发电机、发生器Gland 密封套Gland seal 轴封Goal 目的、目标Go on 继续Grease 图形Green 绿色Ground/earth 地、大地Group 组、群Hardware 硬件Hazardous 危险的、冒险的Hertz HZ 赫兹History 历史Hold 保持Home 家、处所Horse power 马力Hot 热的Hot air 热风Hour 小时Idiostaic 同电位的Idle 空载的、无效的Ignore 忽视Illustrate 说明Impedance 阻抗Import 进口、引入Impulse 脉冲、冲击、冲量Inch IN 英寸Index 索引、指示Indicator 指示器Individual 单个的、独立的Inductive reactance 感抗Input/output I/O 输入/输出Inductance 电感Induction motor 异步电动机Industry 工业Inhibit 禁止Initial 最初的Inlet 入口Input group 输入组Insert 插入Inside 内侧、内部Inspection 观察、检查Install 安装Instruction 说明书、指南、指导Instrument 仪器Insulator 绝缘子Intake 输入端、进线Integer 整数Integral 积分Intensity 强度Interface 接口Interference 干扰、干涉Interlock 联锁Intermediate 中间的Internal 内部的Interrogation 质问、问号Interval 间隔Invoice INV 发票、发货单、托运Invalid 无效的、有病的Isolation 隔离Job 工作Jumper 跳线、跨接Key 键销、钥匙、键槽Keyboard 键盘Kilovolt-ampere KVA 千伏安Kink 弯曲、缠绕Knack 技巧、窍门、诀窍Label 标号、标签Laboratory 实验室Ladder 梯子、阶梯Ladder diagram 梯形图Lamp 灯、光源Last 最后的Leak 泄漏(动词)Leakage 泄漏(名词)Left 左Length 长度Level 液位、水平Lifebelt 安全带、保险带Lift 提、升Light 光亮、点、点燃、照亮. Lightning 雷电Light run 空转Lightning arrestor 避雷器Limit LMT 极限、限制Limiter 限制器、限位开关Line 线、直线impedance 线路阻抗Linkage 连杆List 列表Liter 公升Load 负荷limit 限制Loading 加负荷Local 局部Lock 闭锁、密封舱、固定Logic 逻辑Long 长Loop 环、回路Loss 损失、减少Loss of excitation 励磁损失Loss of phase 失相Low 低Low-half 下半Lower 较低的、降低Lub oil 润滑油Magenta 品红色Magnet 磁Main steam 主蒸汽Make up 补充(补给)Makers works 制造厂Malfunction 出错、误动、失灵Management 管理、控制、处理Manhole 人孔、检查孔、出入孔Manometer 压力表Manual 手动、手册Mark 型号、刻度、标志、特征Mass memory 大容量存储器Master 主要、控制者Maximum 最高的、最大Mean 平均值、中间的Measure 量度、测量Mechanical 机械的、力学的Mechanism 机械、力学、方法Medial 中间的、平均的Mediate 间接的、调解Medium 装置、介质、工质Memory 存储Metal 金属Meter 集量器、仪表、米Method 方法、规律、程序Method of operation 运行方式Mica 云母Microcallipers 千分尺Middle MID 中间的Minimum 最小的Minus 减、负号Minus phase 负相位Minute 分钟Miss operation 误动作、误操作Mistake 错误、事故Mixture 混合物Modify 修改Modulating control 调节控制Module 模件Moisture 湿度、湿汽Monitor 监视器、监视. Mount 安装、固定Mountain cork 石棉Mouse 鼠标Move 移动Multimeter 万用表Multiplication 乘Name 名、名字Natural 自然的Naught line 零线Negative 负的Neon tester 试电表Network 网络Neutral 中性的Neutral point 中性点Next 其次的Nipper 钳子、镊子Noise 噪音No-loading 空载Nominal power 额定功率Non-work 非工作的Normal 正常的、常规的Not available 无效、不能用Number 数字、号码、数目Number of turns 匝数Nut 螺母、螺帽Occur 发生Odd 奇数Office 办公室Oil 油On/off 开/关Onset 开始、发作Open 开、打开Open-air 露天的、开启的Open-loop 开环Open work 户外作业Operation 操作、运行Operational log 运行记录Operator 操作员Optimal 最优的、最佳的Optimal value 最佳值Optional 可选的Option switch 选择开关Original 初始的、原始的Out 出、出口Outage 停用Outlet 出口Output 产量、产品、输出Outside 外边、外面Over current 过流Over load 过负荷Overload protection 过载保护Over voltage 过压Overflow 溢流Overhead 顶部Override 超越Overspeed 超速Overview 概述、总述Oxygen 氧Pad 瓦、衬垫Page 页Panel 屏、盘Parameter 参数Part 部分、部件Password 口令Path 路线Peak 峰值Pendant 悬吊Perfect 完全的、理想的Performance 完成、执行、性能Periodic 周期的、循环的Peripheral 周围的Permanent 永久的、持久的Permit 允许Petrol 汽油Phase PH 阶段、状态、方面、相Phase angle 相角Phase not together 缺相、失相Phase sequence 相序Phase-in 同步Piezometer 压力计Pilot 导向、辅助的、控制的Pilot bearing 导向轴承Pipe 管、管道Plan 计划Plant 工场、车间Plastics 塑料Plug 塞子、栓、插头Plug socket 插座Plus 加Plyers 钳子、老虎钳Point 点Phase voltage 相电压Pole 机、柱Pollution 污染Pop valve 安全阀、突开阀Portion 一部分Position POS 位置Positive 确定的、正的、阳性的Potable water 饮用水Pound LB 磅Power PWR 功率、电源Power factor 功率因子Power plant 电厂Preliminary 准备工作Present 出现Preset 预设、预置Pressure PRES 压力Primary 初级的、一次的Prime 首要的Printer 打印机Principle 原理、原则Priority 优先级、优点Probe 探头Process 过程、方法Processing time 处理时间Program 程序Programmable 可编程的Prohibit 禁止Protection PROT 保护Potential transformer PT 电压互感器Psig 磅/平方英寸(表压力)Psia 磅/平方英寸(绝对压力)Pulse 脉冲、脉动Pump 泵Purge 净化、吹扫Purify 纯度Purpose 目的、用途Push button 按钮Put into operation 投入运行Pyrology 热工学Q-line Q线Quad 回芯组线Quality 质量Quartz 石英、水晶Query 询问、查询Quick 快Quick open 快开Quit 停止、离开、推出Rack earth 机壳接地Radial 径向的、半径的Radication 开方Radiation fin 散热片Raise 升高Range 范围、量程Rap 敲打Rapid charge 快速充电Rated 额定的、比率的Rated conditions 额定条件Rated power 额定功率Ratio 比率Raw material 原材料Ray 光线、射线Reactance 电抗、反作用Reactive capacity 无功容量Reactive power 无功功率Ready 准备好Real power 有效功率Real time 实时的Rear 后面Recipe 处方、配方Recirculate 再循环Recovery 恢复、再生Rectifier 整流器Red 红色Reduction 还原、缩小、降低Reference REF 参考、参照、证明书Reflux 倒流、回流Region 地域、领域Regulate 调节、控制Relative REL 相对的Release 释放Reliability 可靠的、安全的Relief 去载、卸载、释放、解除Renewal 更新、更换Repair 修理Repairer 修理工、检修工Repeat 重复、反复Replacement parts 备件、替换零件Request REO 请求Require 要求Reserve parts 备件Reserved 备用的Reset 复位Resistance 阻力、电阻Resonate 谐振、调谐Response 响应Return 返回Reverse rotation 反转Review 检查Rig 安装、装配、调整Right 右Ring 环Root 跟Rotating 旋转Rotor 转子Run 运行Run back 返回Safe 安全的、可靠的、稳定的. Safe potential 安全电压Safety 安全Saturate 饱和Scan 扫描Screw 螺杆、螺丝Screwdriver 螺丝刀Sea 海Search 寻找、查找Second 秒、第二Seep 渗出、渗漏Select 选择Sensor 传感器Sensitive 灵敏器Sequence 顺序、序列Service 服务、伺服Servomotor 伺服电机Set 设定Set up 安装、调整、建立Shadow 影子、屏蔽Shake 摇动、振动Shaped 形状Share 共享、分配. Sheet 表格、纸张Shell 壳Short circuit 短路Shot 发射、冲击、钢粒Shut off 关闭Shutdown 停止、停机Side 侧边Sidewall 侧墙Signal 信号Sign 标记、注册Silicon SI 硅Silo 灰库Single 单个的、个体的Simple 单纯的、简单的Similar 同样的、类似的Simulator 仿真机Site 现场Size 尺寸、大小Soft 软的、柔软的Software 软件Solid 固体Source 源、电源. Speed 速度Square 广场、方的Stability 稳定(性)Standard 标准Start 启动、开始Start up 启动State 状态Static 静电Stator 静子Stator coil 定子线圈Stator core 定子铁芯Status 状态Steadiness 稳定性Step 步Stere 立方米Stop 停止Storage 储存Straight 直的、直线Subject 题目、科目Supply 供给Support 支持、支撑Sure 确信的、可靠的System 系统Tab 表格Tandem 串联Tank 箱Tap 抽头、分布Target 目标Temperature 温度Template 模板、样板Tensile 拉力的、张力的Text 出口Terminal 端子、接线柱Test 试验Thermal 热的/热量的/由热驱动的Thermal conduction 热传导Thermal convection 热对流Thermal couple 热电偶Thermal cycle 热力循环Thermal radiation 热辐射Thermometer 温度计Thickness 厚度、浓度Third 第三Throttle 节流Thumb rule 安培右手定则Tight 紧密的Tilt 倾斜Tilting 摆动Title 题目、标题Total 总计的To 到、去Token 标志Tool 工具Tool box 工具箱Torque 扭矩、力矩Track 跟踪Travel 过程、运转、进行、移动Trend 趋势、方向Trip 跳闸、断开Trouble 事故、故障、干扰True 真实的、调整、校正TUNE 调节Tuning 调谐Tweezers 镊子、钳子Type 类型、标志Unbuild 失磁. Unit 单元、机组、电池Unload 减负荷Unlock 打开、解锁、释放Unprotected 未保护的、无屏蔽的Up 向上Up-half 上部、上半Update 更新、修改、校正Upgrade 升级(优先级)提高/改进Upper 上部Use 使用User 用户Valid 有效地、正确Value 数值Variable 可变的、可调的Vector 失量、向量Vessel 容器Vibration 振动Voltage transformer 电压互感器Voltmeter 电压表Volume 容积、体积Wall 墙、壁Wash 洗. Weather 天气Weak 星期、周Weight 重量Weld 焊接White 白色Windbox 风箱Windings 绕组Windows 窗口Wire 电绕Wire stripper 剥线钳Wood 木、木制的Work 工作Year 年Yellow 黄色Zero 零Zone 区、层、带。
步进电机的的基本原理中英文翻译
步进电机的的基本原理中英文翻译English translation of the stepping motor basic principle步进电机作为执行元件,是机电一体化的关键产品之一,广泛应用在各种自动化控制系统中。
随着微电子和计算机技术的发展,步进电机的需求量与日俱增,在各个国民经济领域都有应用。
The stepping motor as executing components, electromechanical integration is one of the key products, widely used in a variety of automatic control systems. With the development of microelectronics and computer technology, the stepper motor demand grow with each passing day, has been applied in various fields of the national economy.步进电机是一种将电脉冲转化为角位移的执行机构。
当步进驱动器接收到一个脉冲信号,它就驱动步进电机按设定的方向转动一个固定的角度(称为“步距角”),它的旋转是以固定的角度一步一步运行的。
可以通过控制脉冲个数来控制角位移量,从而达到准确定位的目的;同时可以通过控制脉冲频率来控制电机转动的速度和加速度,从而达到调速的目的。
步进电机可以作为一种控制用的特种电机,利用其没有积累误差(精度为100%)的特点,广泛应用于各种开环控制。
Stepping motor is a kind of electrical pulses into angular displacement of the implementing agencies. When stepping drive receives a pulse signal, it drives stepper motor rotate in the direction set by a fixed angle ( called the " step " ), it is the rotation at a fixed angle step by step operation. The number of pulses to control the amount of angular displacement through the control, so as to achieve the purpose of accurate positioning; also can control the pulse frequency to control motor rotation speed and acceleration, so as to achieve the purpose of speed. Special motor stepper motor control can be used as a, using its no accumulation of error ( accuracy of 100% ) characteristics, widely used in all kinds of open-loop control.现在比较常用的步进电机包括反应式步进电机(VR)、永磁式步进电机(PM)、混合式步进电机(HB)和单相式步进电机等。
基于单片机的步进电机控制系统设计外文资料翻译
毕业设计(论文)外文资料翻译学院:机械工程学院专业:机械设计制造及其自动化姓名:张XX学号:XXXXXXXXXX外文出处:《Computational Intelligence and (用外文写)Design》附件: 1.外文资料翻译译文;2.外文原文。
注:请将该封面与附件装订成册。
附件1:外文资料翻译译文基于微型计算机的步进电机控制系统设计孟天星余兰兰山东理工大学电子与电气工程学院山东省淄博市摘要本文详细地介绍了一种以AT89C51为核心的步进电机控制系统。
该系统设计包括硬件设计、软件设计和电路设计。
电路设计模块包括键盘输入模块、LED显示模块、发光二极管状态显示和报警模块。
按键可以输入设定步进电机的启停、转速、转向,改变转速、转向等的状态参数。
通过键盘输入的状态参数来控制步进电机的步进位置和步进速度进而驱动负载执行预订的工作。
运用显示电路来显示步进电机的输入数据和运行状态。
AT89C51单片机通过指令系统和编译程序来执行软件部分。
通过反馈检测模块,该系统可以很好地完成上述功能。
关键词:步进电机,AT89C51单片机,驱动器,速度控制1概述步进电机因为具有较高的精度而被广泛地应用于运动控制系统,例如机器人、打印机、软盘驱动机、绘图仪、机械式阀体等等。
过去传统的步进电机控制电路和驱动电路设计方法通常都极为复杂,由成本很高而且实用性很差的电器元件组成。
结合微型计算机技术和软件编程技术的设计方法成功地避免了设计大量复杂的电路,降低了使用元件的成本,使步进电机的应用更广泛更灵活。
本文步进电机控制系统是基于AT89C51单片机进行设计的,它具有电路简单、结构紧凑的特点,能进行加减速,转向和角度控制。
它仅仅需要修改控制程序就可以对各种不同型号的步进电机进行控制而不需要改变硬件电路,所以它具有很广泛的应用领域。
2设计方案该系统以AT89C51单片机为核心来控制步进电机。
电路设计包括键盘输入电路、LED显示电路、发光二极管显示电路和报警电路,系统原理框图如图1所示。
步进电机PLC控制技术中英文对照外文翻译文献
中英文对照外文翻译文献(文档含英文原文和中文翻译)The shallow treads into the PLC control technique and development trend of electrical engineering1. Say all:Along with the micro-electronics technique and the calculator technical hair Exhibition, the programmable preface controller has an advance by leaps and bounds of hair Exhibition, its function has already outrun a logic control far and far, in proper order The scope of control, it has an effect to combine with calculator, can enter Go to imitate to control most, have along range correspondence function etc.. Have-The person is called it the modern D industry controls of three pay pillar greatly(namely PLC, robot, CAD/CAM)it a, currently programmable controller BE applied in metallurgy extensively, Mineral industry, machine, light Class D realm, automate for the industry Provided to there is the tool of one dint The PLC controls of tread to open the wreath servo organization into the electrical engineering should Used for combining tool machine to produce an on-line number to control a slippery pedestal to control automatically Make, can the province go to the number of that unit to control system, making that unit The cost of controlling the system lowers.2、What is a stepper motor:Stepper motor is a kind of electrical pulses into angular displacement ofthe implementing agency. Popular little lesson: When the driver receives a step pulse signal, it will drive a stepper motor to set the direction of rotation at a fixed angle (and the step angle). You can control the number of pulses to control the angular displacement, so as to achieve accurate positioning purposes; the same time you can control the pulse frequency to control the motor rotation speed and acceleration, to achieve speed control purposes.What kinds of stepper motor sub-:In three stepper motors: permanent magnet (PM), reactive (VR) and hybrid (HB) permanent magnet stepper usually two-phase, torque, and smaller, step angle of 7.5 degrees or the general 15 degrees; reaction step is generallythree-phase, can achieve high torque output, step angle of 1.5 degrees is generally, but the noise and vibration are large. 80 countries in Europe and America have been eliminated; hybrid stepper is a mix of permanent magnet and reactive advantages. It consists of two phases and the five-phase: two-phase step angle of 1.8 degrees while the general five-phase step angle of 0.72 degrees generally. The most widely used Stepper Motor. What is to keep the torque (HOLDING TORQUE)3、Tread into the basic characteristics of electrical engineering:(1)、tread generally into the accuracy of the electrical engineering for tread into Cape of 3-5% and don't accumulate.(2)、tallest temperatures which enter electrical engineering outward appearance and allow tread and lead into the electrical engineering temperature high can make the magnetism material of electrical engineering back first, cause the dint descend thus is as for lose a step, so the electrical engineering outward appearance allow of the tallest temperature should be decided by small back with electrical engineering magnetism material and order; Speak generally, the magnetism material backs to order all above have in 130 C an of even be up to 200C above, so tread completely normal into the electrical engineering outward appearance temperature in 80-90C.(3)、dints which enter electrical engineering would with turn to go up but descend soon,While treading to turn to move into the electrical engineering,electrical engineering each electricity feeling which round a set mutually will become one anti- to electromotive force; The frequency is more high, anti- to electromotive force more big ,big in its function, the electrical engineering enlarges with the frequency(or speed) but mutually the electric current let up, causing the dint descend thus.(4)、can revolve normally when 4 enter electrical engineering low speed, but if high in certain the speed can't start, and the companion have a roar the interjection tread to have a technique parameter into the electrical engineering: empty carry start frequency, then tread into electrical engineering at empty carry under circumstance can start normally of pulse frequency, if the pulse frequency is high in should be worth., The electrical engineering can't start normally, the possible occurrence throws a step or blocks up to turn. Under the situation that there is one load, the start frequency should be much lower if want to make the electrical engineering attain high speed to turn to move, the pulse frequency should have an acceleration process, then start the frequency is lower, then press certain acceleration to rise the high hoped. Tread to show the characteristics of with it into the electric motor, turn ages of manufacturing to develop important use to accompany with in the numeral small together of numeral turn technical of development and tread into the electrical engineering technical exaltation,tread will get an application in more realms into the electrical engineering.4、enter an electrical engineering control system to constitute:Tread is a kind of performance organization that will give or get an electric shock a pulse conversion to move for the Cape into the electrical engineering. When tread to receive to a pulse signal into the actuator, it drives a step to press the direction of enactment to turn to move an angle for fixing to be called "tread to be apart from Cape" into the electrical engineering, it revolves one-step circulate with the fixed angle one step. Can pass control pulse piece to control a Cape to move to attain the purpose of assurance most and thus; Can pass control pulse frequency to control electrical engineering to become dynamic speed and acceleration in the meantime, the purpose attained to adjust thus soon treads into the electrical engineering. Can be the special kind electrical engineering that a kind of control uses, make use of it didn't accumulate error margin accuracy to 100 to divide 100 of characteristics, be suffused with to apply in various open a wreath control PLC which enter electrical engineering technique.5、Stepper motor of the PLC control technology:Make the importation tread to be subjected to a homologous control into total amount and pulse frequency of the importation pulse of electrical engineering. Establish the pulse signal occurrence that a pulse total amount and pulse frequency can control a machine therefore and in control,software; Can make use of PL in fixed time a machine composing for the frequency lower control pulse, the pulse frequency can pass in fixed time machine in fixed time constant control pulse period, the pulse amounts control then can establish a the pulse counter C10 be when the pulse number attain initial value, count machine C1.The action cuts off pulse back track, making it stop, the servo organization tread into the electrical engineering have no the pulse input then stop operation,servo performance organization fixed position be servo performance organization of when move speed to have higher request, can use PLC high-speed pulse,Different PLC it the frequency of high-speed pulse can reach to 4000-6000Hzses. The PLC is used to produce control pulse, passing PLC plait distance exportation several pulses certainly the control treads to turn Cape into the electrical engineering, programmable controller output's control the pulse enters electrical engineering to switch on electricity sequence to assign by the step homologous of round a set. The PLC controls of tread can go an allotment machine by adoption software wreath into the electrical engineering, the hardware wreath goes allotment machine to adopt the PLC resources that the soft wreath takes up more, Tread especially to round a set to count mutually into the electrical engineering big should consider adoption hardware wreath to go allotment machine well for large production line at 4, although the hardware structure is a little bit a little more complicated, can save an exportation importation of taking up the PLC point, the market has a various appropriation chips to choose to use currently. Tread to enlarge to several ten highest hundred folds into the output's control of the actuator PLC of the electrical engineering power pulse, volt, several Anne arrive several ten several Anne s drive an ability, the exportation of general PLC connects to have to certainly drive an ability, but inside usual transistor flow exportation to connect an ability only for ten several arrive several ten volts, several ten arrive several 100 million Anne but tread to then have several request into the electrical engineering to the power ten arrive up 100 volts, several Anne arrive several ten Anne s drive an ability so should adopt an actuator to output the pulse carry on enlarging.6、Application features of PLC(1)、High reliability, strong anti-interferenceHigh reliability is the key to performance of electrical control equipment. PLC as the use of modern large scale integrated circuit technology, using the strict production process, the internal circuits to the advanced anti-jamming technology, with high reliability. Constitute a control system using PLC, and the same size compared to relay contactor system, electrical wiring and switch contacts have been reduced to hundreds or even thousands of times, fault also greatly reduced. In addition, PLC hardware failures with self-detection, failure alarm timely information. In the application software, application are also incorporated into the peripheral device fault diagnosis procedure, the system is in addition to PLC circuits and devices other than the access protection fault diagnosis. In this way, the whole system extremely high reliability.(2)、Fully furnished, fully functional, applicabilityPLC to today, has formed a series products of various sizes, can be used for occasions of all sizes of industrial control. In addition to processing other than logic, PLC data, most of computing power has improved, can be used for a variety of digital control in the field. A wide variety of functional units in large numbers, so that penetration to the position of PLC control, temperature control, CNC and other industrial control. Enhanced communication capabilities with PLC and human-machine interface technology, using the PLC control system composed of a variety of very easily.(3)、Easy to learn, well engineering and technical personnel welcome PLC is facing the industrial and mining enterprises in the industrial equipment. It interfaces easily, programming language easily acceptable for engineering and technical personnel. Ladder language, graphic symbols and expressions and relay circuit very close to are not familiar with electronic circuits, computer principles and assembly language do not understand people who engage in industrial control to open the door.(4)、System design, the workload is small, easy maintenance, easy to transformPLC logic with memory logic instead of wiring, greatly reducing the control equipment external wiring, make the control system design and construction of the much shorter period, while routine maintenance is also easier up, even more important is to change the procedures of the same equipment has been changedproduction process possible. This is particularly suitable for many varieties, small batch production situations.7、The development trend of 5 domestic and international electrical engineering: (1)、continue along small scaled direction development turned along with electric motor application the realm open widely and each kind of whole machine is continuously small scaled to turn, the electric motor which requests with its kit have to also more and more small, at 57, the electric motor of 42 machine seat numbers applies many after years, now its machine seat number to 39,35,30,25 directions get down extension.(2 )、right nesses of electric motors carry on comprehensive design namely turn soon position to spread a feeling machine, decelerate the wheel gear etc. and electric motor essence to synthesize design together, so make it be able to constitute 1 to shut wreath system expediently, as a result have one more superior control function.(3)、to five mutually with three mutually the electric motor direction develop,Be suffused with currently applied of two mutually with four mutually the electric motor, its vibration and voice are bigger, but five mutually with three mutually the electric motor have advantage but in regard to these two kinds of electric motors, five mutually the electric motor drive electric circuit compare. 8、Conclusion:At present, the use of programmable process controller (that is, the PLC technology) can easily realize the control of motor speed and the position of the convenient, c onvenient for a variety of stepper motor operation, t o complete a variety of complex work. It represents the advanced industrial automation revolution; accelerate the realization of the electromechanical integration.浅析步进电机的PLC控制技术与发展趋势1、概述随着微电子技术和计算机技术的发展,可编程序控制器有一了突飞猛进的发展,其功能已远远超出了逻辑控制、顺序控制的范围,它与计算机有一效结合,可进行模拟最控制,具有一远程通信功能等。
步进电机概述论文翻译英文版(5篇模版)
步进电机概述论文翻译英文版(5篇模版)第一篇:步进电机概述论文翻译英文版Knowledge of the stepper motor What is a stepper motor:The stepping motor as executing components, electromechanical integration is one of the key products, widely used in a variety of automatic control systems. With the development of microelectronics and computer technology, the stepper motor demand grow with each passing day, has been applied in various fields of the national economy.Stepping motor is a kind of electrical pulses into angular displacement of the implementing agencies. When stepping drive receives a pulse signal, it drives stepper motor rotate in the direction set by a fixed angle ( called the " step " ), it is the rotation at a fixed angle step by step operation. The number of pulses to control the amount of angular displacement through the control, so as to achieve the purpose of accurate positioning; also can control the pulse frequency to control motor rotation speed and acceleration, so as to achieve the purpose of speed. Special motor stepper motor control can be used as a, using its no accumulation of error ( accuracy of 100% ) characteristics, widely used in all kinds of open-loop control.Now more commonly used step motor comprises stepper motor ( VR ), permanent magnet stepper motor ( PM ), hybrid stepping motor ( HB ) and single-phase stepping motor.Permanent magnet stepper motor for general two-phase, torque and small volume, the step angle is 7.5 degree or 15 degree;Reaction stepping motor is generally three-phase, can achieve a high torque output, step angle is 1.5 degrees, but thenoise and vibration are great. The rotor magnetic circuit made of soft magnetic material reaction stepper motor, a multi-phase excitation winding stator, using magnetic torque changes.Hybrid stepping motor is mixed the advantages of permanent magnet type and reaction type. It is divided into two phase and five phase: two-phase stepper angle is 1.8 degree and five phase stepper angle is 0.72 degrees. Application of the stepping motor is the most widely, is also this subdivision driving of stepper motor selection scheme.Some of the basic parameters of step motor:The natural step motor:It says every hair a step pulse signal control system, motor rotation angle. Motor factory is a step angle values, such as type 86BYG250A motor is given a value of 0.9° /1.8 °( said a half step of work is 0.9 °, the whole step of work is 1.8 °), this step can be called ' motor fixed step ', it doesn't have to be the actual motor work when the real step angle, angle and drive the real steps.Stepper motor phase number:Is the number of coils inside the motor, commonly used in a two-phase, three-phase, four phase, five phase stepper motor. The number of motor phase is different, the step angle is also different, the general two-phase motor step angle is 0.9° /1.8 °, three-phase 0.75 ° /1.5 °, five phase of 0.36 ° /0.72 °. In the absence of subdivision drive, users mainly rely on different phases of the stepper motor to meet their own requirements of step angle. If you use a subdivision driver, is ' phase ' will become meaningless, users only need to change the fine fraction in the drive, you can change the step angle.Keep the torque ( HOLDINGTORQUE ):Is the stepper motor power but there is no rotation, thestator locked rotor torque. It is one of the most important parameters of step motor, usually stepper motor in the low-speed torque to keep the torque. Because of the larger output torque stepper motor with speed and continuous decay, increases the output power with the speed of change, so keep the torque becomes one of the most important parameters of step motor. For example, when people say 2N.m stepper motor, in the absence of exceptional circumstances described in that refers to keep the torque motor for the 2N.m step.DETENTTORQUE: DETENTTORQUE:Refers to the stepper motor is not energized condition, the stator locked rotor torque. DETENTTORQUE does not have a unified way of translation in China, easy to make people misunderstand; as the rotor reaction stepper motor is not permanent magnetic material, so it has no DETENTTORQUE.Some of the characteristic of step motor:The 1 stepper motor step angle accuracy for 3-5%, and no accumulation.2 stepper motor appearance allows the maximum temperature.Stepper motor temperature is too high will first make the motor magnetic material demagnetization, resulting in lower torque and loss, so the highest temperature of motor appearance allows should depend on the different motor demagnetization magnetic materials; generally speaking, demagnetization point magnetic material in 130 degrees Celsius above, some even as high as 200 degrees Celsius stepping motor, so the surface temperature at 80-90 degrees Celsius completely normal.3 stepper motor torque will decrease with the increase of rotational speed.When the stepper motor rotates, the electrical inductance of the winding will form a reverse electromotive force; the higher the frequency, the greater the reverse emf. Under the influence of it, the motor with frequency ( or speed ) increase and the phase current is reduced, resulting in lower torque.4 stepper motor speed can be normal operation, but if it is more than a certain speed will not start, and accompanied by howling.Stepper motor is a technical parameter: no-load start frequency, namely the stepper motor under no-load condition can pulse frequency start, if the pulse frequency is higher than the value, the motor can not start properly, may have lost step or stall. In under the condition of the load, start frequency should be less. If you want to enable the motor to rotate at high speed, pulse frequency should accelerate the process is started, the lower frequency, and then according to certain acceleration up to high frequency desired ( motor speed from low speed to high speed ).Characteristics of stepper motor with its significant, play an important purpose in the era of digital manufacturing. With the different development of digital technology and stepper motor itself technology improves, the stepper motor will be applied in more fields. How to determine the stepper motor driver DC power supply:A. Determination of the voltageHybrid stepping motor driver power supply voltage is generally a wide range (such as the IM483 supply voltage of 12 ~ 48VDC), the supply voltage is usually based on the work of the motor speed and response to the request to choose. If the motor operating speed higher or faster response to the request, thenthe voltage value is high, but note that the ripple voltage can not exceed the maximum input voltage of the drive, or it may damage the drive. B. Determination of Current Power supply current is generally based on the output phase current drive I to determine. If a linear power supply, power supply current is generally preferable 1.1 to 1.3 times the I; if we adopt the switching power supply, power supply current is generally preferable to I, 1.5 to 2.0 times. The main characteristics of stepping motor:A stepper motor drive can be added operate pulse drive signal must be no pulse when the stepper motor at rest, such as If adding the appropriate pulse signal, it will to a certain angle (called the step angle) rotation. Rotation speed and pulse frequency is proportional to.2 Dragon step angle stepper motor version is 7.5 degrees, 360 degrees around, takes 48 pulses to complete.3 stepper motor has instant start and rapid cessation of superior characteristics. Change the pulse of the order of 4, you can easily change the direction of rotation. Therefore, the current printers, plotters, robotics, and so devices are the core of the stepper motor as the driving force. Stepper motor control example We use four-phase unipolar stepper motor as an example. The structure shown in Figure 1:Four four-phase winding leads (as opposed to phase A1 A2 B1 phase phase B2) and two public lines (to the power of positive). The windings of one phase to the power of the ground. So that the windings will be inspired. We use four-phase eight-beat control, ie, 1 phase 2 phase alternating turn, would enhance resolution. 0.9 ° per step can be transferred to control the motor excitation is transferred in order as follows:If the requirements of motor reversal, the transmission excitation signal can be reversed. 2 control scheme Control system block diagram is as followsThe program uses AT89S51 as the main control device. It is compatible with the AT89C51, but also increased the SPI interface and the watchdog module, which not only makes the debugging process becomes easy and also more stable. The microcontroller in the program mainly for field signal acquisition and operation of the stepper motor to calculate the direction and speed information. Then sent to the CPLD. CPLD with EPM7128SLC84-15, EPM7128 programmable logic device of large-scale, for the ALTERA company's MAX7000 family. High impedance, electrically erasable and other characteristics, can be used for the 2500 unit, the working voltage of +5 V. CPLD receives information sent from the microcontroller after converted to the corresponding control signal output to the stepper motor drive. Put the control signal drives the motor windings after the input, to achieve effective control of the motor.2.1 The hardware structure of the motor drive Motor drive using the following circuit:R1-R8 in which the resistance value of 320Ω. R9-R12 resistance value 2.2KΩ. Q1-Q4 as Darlington D401A, Q5-Q8 for the S8550. J1, J2 and the stepper motor connected to the six-lead。
步进电机运动控制系统外文文献翻译中英文
步进电机运动控制系统外文文献翻译中英文外文文献翻译(含:英文原文及中文译文)文献出处:YH Lee. Stepper motor motion control system design [J]. Equipment Manufacturing Technology, 2015,2(6):31-41.英文原文Stepper motor motion control system designYH LeeAbstractStepper motors are open-loop control elements that convertelectrical pulse signals to angular or linear displacements. In the case of non-overload, the rotation speed and stop position of the motor depend only on the frequency and pulse number of the pulse signal, and is not affected by the load change, that is, a pulse signal is applied to the motor, and the motor rotates through a step angle. The existence of this linear relationship, coupled with the fact that the stepper motor has only periodic errors and no cumulative errors, is a feature. It is very simple to use a stepper motor to control the speed and position. Stepper motor speed control is generally to change the frequency of the input stepper motor pulse to achieve stepper motor speed control, because the stepper motor for each pulse to rotate afixed angle, so that you can control the stepper motor The time intervalfrom one pulse to the next pulse changes the frequency of the pulse. The length of the delay controls the step anglespecifically to change the rotation speed of the motor, thereby realizing the stepping motor speed control. In this design scheme, the internal timer of the AT89C51 microcontroller is used to change the frequency of the CP pulse to realize the control of the rotation speedof the stepper motor to realize the functions of the motor speed adjustment and forward and reverse rotation. The design takes into consideration that the CPU may be disturbed when executing instructions, causing the program to "run away" or enter the "endless loop". Therefore, the watchdog circuit is designed using a microprocessing system monitoring integrated chip manufactured by MAXIM. MAXI813. This article also gives the related hardware block diagram and software flow chart in detail, and has compiled the assembly language program.Keywords: stepper motor single chip microcomputer speed control systemIntroductionStepper motors were first developed by the British in 1920. The invention of the transistor in the late 1950s was also gradually applied to a stepping motor, which made it easier to control the digitization. After continuous improvement, today's stepper motors have been widely used in mechanical systems with high controllability such as high positioning accuracy, high decomposition performance, highresponsiveness, and reliability. In the production process, where automation, labor saving, andhigh efficiency are required, we can easily find traces of stepper motors, especially those that emphasize speed, position control, and flexible control applications that require precise command operation. The most. As an actuator, a stepper motor is one of the key products of electromechanical integration and is widely used in various automation control systems. With the development of microelectronics and computer technology, the demand for stepper motors is increasing day by day, and there are applications in various national economic fields. A stepper motor is an actuator that converts an electrical pulse signal into an angular or linear displacement. Stepper motors can be driven directly with digital signals and are very easy to use. The general motor is continuous rotation, while the stepper motor has two basic states of positioning and operation. When there is a pulse input, the stepping motor rotates step by step, and when it is given a pulse signal, it turns a certain angle. The angular displacement of the stepping motor is strictly proportional to the number of input pulses and is synchronized in time with the input pulse. Therefore, as long as the number of input pulses, the frequency, and the phase sequence of the motor windings are controlled, the desired rotation angle can be obtained. Speed and direction of rotation. When there is no pulse input, the air gap magnetic field can keep the rotor in the original position under theexcitation of the winding power supply. So it is very suitable forsingle chip microcomputer control. Stepper motors also have features such as fast start, precise stepping and positioning, and are thus widely used in CNC machine tools, plotters, printers, and optical instruments. Stepping motors have become the third category of motors except for DC motors and AC motors. Traditional electric motors, as electromechanical energy conversion devices, play a key role in human production and life into the electrification process. The stepper motor can be used as a special motor for control, and it is widely used in various open-loop control because it has no accumulated error (accuracy is 100%). Now more commonly used stepper motors include reactive stepper motors (VR), permanent magnet stepper motors (PM), hybrid stepper motors (HB), and single-phase stepper motors. Permanent-magnet type stepping motor is generally two-phase, small torque and volume, step angle is generally 7.5 degrees or 15 degrees; Reactive stepping motor is generally three-phase, can achieve large torque output, stepping The angle is generally 1.5 degrees, but the noise and vibration are large. The rotor of the reactive stepper motor is magnetically routed from a soft magnetic material, and the stator has a multi-phase excitation winding, which generates torque using a change in the magnetic permeability. Hybrid stepping motor refers to the advantage of mixing permanent magnet type and reactive type. It is divided into two phases and five phases: the two-phase step angle is generally 1.8 degrees andthe five-phase step angle is generally 0.72 degrees. This type of steppermotor is the most widely used and is also the stepper motor used in this subdivision drive scheme.1 stepper motor overview1. 1 stepper motor features:1) The accuracy of a typical stepper motor is 3-5% of the step angle and does not accumulate. 2) The allowable temperature of the stepper motor is high. Excessively high temperature of the stepping motor first demagnetizes the magnetic material of the motor, resulting in a drop in torque and even loss of synchronism. Therefore, the maximum temperature allowed for the appearance of the motor should depend on the demagnetization point of the magnetic material of different motors; generally, the demagnetization of the magnetic material. The points are all above 130 degrees Celsius, and some are even up to 200 degrees Celsius. Therefore, the external temperature of the stepper motor is completely normal at 80-90 degrees Celsius. 3) The torque of the stepper motor will decrease as the rotation speed increases. When the stepper motor rotates, the inductance of each phase winding of the motor will form a counter electromotive force; the higher the frequency, the greater the counter electromotive force. Under its effect, the motor's phase current decreases as the frequency (or speed) increases, causing the torque to drop. 4) The stepping motor can run normally at low speed,but it cannot start if it is higher than a certain speed, accompanied by howling. The stepper motorhas a technical parameter: No-load starting frequency, that is the pulse frequency that the stepping motor can start normally under no-load conditions. If the pulse frequency is higher than this value, the motor cannot start normally, and step loss or stall may occur. In the case of load, the starting frequency should be lower. If the motor is to be rotated at a high speed, the pulse frequency should have an acceleration process, that is, the starting frequency is low, and then it is increased to a desired high frequency (motor speed is raised from low speed to high speed) at a certain acceleration. TC \* MERGEFORMAT1. 2 working principle of stepping motorA stepper motor is a type of motor that is controlled by anelectrical pulse and converts the electrical pulse signal into a phase-shifted motor whose mechanical displacement and rotational speed are proportional to the number of pulses and the pulse frequency of the input motor winding. Each pulse signal can be stepped The feed motor rotates at a fixed angle. The number of pulses determines the total angle of rotation. The frequency of the pulse determines the speed of the motor. When the stepper receives a pulse signal, it drives the stepper motor to rotate in the set direction. At a fixed angle (called "step angle"), its rotation is performed step by step at a fixed angle. By controlling the number of pulses to control the angular displacement,so as to achieve the purpose of accurate positioning; At the same time, by controlling the pulse frequencyto control the speed and acceleration of the motor rotation, so asto achieve the purpose of speed control.2 Basic requirements for designStudy the characteristics, working principle, and specific speed regulation principle of stepper motor. TC \* MERGEFORMATBasic requirements The stepper motor uses a three-phase steppermotor with a power of 1W. When the speed is in the range of 0 to1000r/min, the maximum accuracy is 2%. To basically complete the graduation design, the stepper motor can perform precise speed control, positive and negative rotation, and it can not lose step when starting. Basically, there is no Oscillation, can complete the complete hardware circuit diagram, software design.3 Argumentation of the plan3.1 Determination of control methodsAlthough the stepper motor control is a relatively accurate, open-loop stepper motor control system has the advantages of low cost, simple, convenient control, etc., in the open-loop system of the stepper motor using the microcontroller, the frequency of the CP pulse of the control system or change The cycle is actually controlling the speed of the stepper motor. There are two ways the system can achieve stepper motor speed control. One is delay, the other is timing. The delay method is to call a delay subroutine after each commutation. After the delay isover, the commutation is executed again. In this way, CP pulses or commutation cycles with a certain frequency can be issued. The delay time of the delay subroutine and the time used by the commutation program are the cycles of the CP pulse. This method is simple, uses less resources, and is implemented by software. Different subroutines can be called to achieve different speeds. However, it takes a long time to process the CPU and cannot handle other tasks at runtime. Therefore, it is only suitable for a simpler control process. The timing method is to use the timer timing function in the microcontroller system to generate an arbitrary period of the timing signal, so that the period of the system output CP pulse can be conveniently controlled. When the timer is started, the timer counts up the system and its cycle starting from the loaded initial value. When the timer overflows, the timer generates an interrupt and the system transfers to execute the timer interrupt subroutine. The motor commutation subroutine is placed in the timer interrupt service routine. The timer interrupt is once and the motor is reversed once to achieve motor speed control. Since there is a certain time interval from the start of restarting the timer to the timer application interruption, the timing time is increased. In order to reduce this timing error and achieve accurate timing, it is necessary to make appropriate adjustments to the initial value of reloading counts. . The initial value of adjusted reloading mainly considers two factors and one is the time required to interrupt theresponse. The second is the time occupied by reloading the initial value instruction, including other instructions that interrupt the service program before reloading the initial value. After these two factors are combined, the correction amount of the reload count initial value takes 8 machine cycles, that is, the timing time is shortened by 8 machine cycles. When using the timer interrupt to control the motor shift, it is actually changing the size of the timer load value. In the control process, a discrete approach is used to approximate the ideal speed curve. In order to reduce the time for calculating the load value in each step, the load value required for the speed of each discrete point is fixed in the ROM of the system when the system is designed. The system uses the table look-up method to find the required load value in the system. Significantly reduce the time spent on CPU and improve the response speed of the system. Most stepper motor motion control systems are designed to run in an open-loop state, because the cost is low, and the position control inherent in the motion control technology can be provided without feedback. However, in some applications, more reliability, security, or product quality assurance is required. Therefore, closed-loop control is also an option. Here are some methods for achieving closed-loop control of stepper motors: 1) Step-by-step confirmation, This is the simplest displacement control, using a low-value optical encoder to calculate the amount of step movement. A simple loop compares the stepper motor with the commandverification and verifies that the stepper motor moves to the expected position; 2) Back-EMF, a sensorless detection method, uses a stepper motor's back EMF (eleCtromotiveCe, emf) signal , Measure and control speed. When the back-EMF voltage drops to the monitoring detection level, the closed-loop control is changed to the standard open-loop to complete the final displacement movement; 3) Full-servo control refers to the full-time use of feedback devices for stepper motors - encoders, decoding , or other feedback sensors to more accurately control the stepper motor displacement and torque. Other methods include a variety of different back-EMF control motor parameter measurements and software techniques that some manufacturers use. Here, the stepper drive monitors and measures the motor coils and uses voltage current information to increase the stepper motor control. Positive damping uses this information to block the speed of vibration, producing more usable torque output and reducing torque-induced mechanical vibration losses. No encoder installation monitoring uses information to detect the loss of synchronous speed. Conventional stepper motor control usually employs feedback devices and non-sensing methods, and is an effective method to implement a sports application with safety requirements, dangerous conditions or high accuracy requirements. Most stepper motor-based systems typically operate in an open-loop state, which provides a low-cost solution. In fact, stepper systems can improve the performanceof displacement control without feedback. However, when the stepper motor is running in open loop, there may be a simultaneous loss between the command pace and the actual step. Closed-loop control, which is part of traditional step control, can effectively provide higher reliability, safety, or product quality. In these stepper systems, the closed loop of the feedback device or indirect parametric sensing method can correct or control out-of-step, monitor motor stagnation, and ensure greater available torque output. Recently, closed-loop control (CLC) of stepper motors can also help implement smart distributed motion architectures. However, there is a risk of out-of-step operation in open-loop operation, which will result in positioning errors. However, compared to encoders used in servo systems, closed-loop stepper motors use encoders that are less costly. Therefore, closed-loop control is selected.3.2 Determination of Drive ModeThere are generally two methods for driving a stepping motor. One is directly driven by the CPU. This method is generally not suitable because the output current pulse of the CPU is extremely small and it cannot sufficiently rotate the stepping motor. One is indirect drivingby the CPU, which is to amplify the signal output from the CPU, and then directly drive or indirectly drive the stepper motor throughphotoelectric isolation. This method is relatively safe and reliable. The solid design should use a CPU to drive the stepper motor indirectly. Thetachogenerator of the encoder is also used as the speed measurement tool. Because the closed-loop control is selected, there must be feedback components. There are generally two types of feedback components. One is the coaxial tachometer generator, and the speed of the stepping motor is fed back. Back, and then through the display and stepper motor adjustment; Another is through the optical coaxial encoder to the stepper motor speed feedback back to the stepper motor to adjust; compared to the latter, the latter The design is relatively simple, inexpensive, safe and reliable, and less polluting. The latter is generally used for solids, and photoelectric crumblers are used as feedback components.3. 3 Selection of Drive CircuitThere are many kinds of driving motors for stepping motors, but the most common ones are single voltage driving, dual voltage driving, chopper driving, subdivision control driving and so on. Single-voltage driving is the simplest driving circuit in stepper motor control. It is essentially a single-phase inverter. Its greatest feature is its simple structure, because of its low work efficiency, especially its prominent features at high frequencies. Its external resistor R consumes a considerable amount of heat, which affects the stability of the circuit. This type of drive is generally used only in the drive circuit of a low-power stepper motor. Dual-voltage driving is generally driven by two power supply voltages. Since these two power supplies are one highvoltage and one low voltage, they are also called high and low voltage driving circuits. The disadvantage of the dual-voltage driving circuit is that the valley point appears in the current at the high-low voltage connection, which inevitably causes the torque to drop at the valley point. Not suitable for normal operation of the motor. For the chopper circuit drive, this disadvantage can be overcome and the efficiency of the stepper motor can also be improved. Therefore, it is a good driver circuit from the standpoint of improving efficiency. It can use a higher power supply voltage and does not require an external resistor to limit the rated current and reduce the time constant. However, due to the sawtooth fluctuations at the top of the waveform, large electromagnetic noise is generated. The subdivision drive is powered by a pulse voltage. For a voltage pulse, the rotor can rotate one step. Generally, according to the voltage pulse distribution method, each phase winding of the stepping motor will alternately switch, and the rotor of the stepping motor can be fixed. Rotate. The subdivided control circuit is generally divided into two types. One is to use a linear analog power amplifier to obtain a staircase current. This method is simple but inefficient. The other method is to use a single-chip microcomputer to obtain the step current by using the method of pulse width modulation. This method requires complex calculations to make the substepped step angles uniform. However, due to the fact that the design of the stepper motor requires a relatively wide range ofhigh-speed adjustments, the drive chip 8713 should be used to drive themotor and the speed of the stepper motor must be controlled by software.中文译文步进电机运动控制系统设计作者:YH Lee摘要步进电机是将电脉冲信号转变为角位移或线位移的开环控制元件。
步进电机外文翻译
附录2:英文资料及其中文翻译Stepper motor is an electrical pulse will be converted into angular displacement of the implementing agencies. Put it in simple language-speaking: When the stepper drive pulse signal to a receiver, it drives stepper motor rotation direction by setting a fixed point of view (and the step angle). You can control the number of pulses to control the amount of angular displacement, so as to achieve the purpose of accurate positioning; At the same time, you can by controlling the pulse frequency to control the motor rotation speed and acceleration, so as to achieve the purpose of speed.Stepper motor directly from the AC-DC power supply, and must use special equipment - stepper motor drive. Stepper motor drive system performance, in addition to their own performance with the motor on the outside, but also to a large extent depend on the drive is good or bad. A typical stepper motor drive system is operated by the stepper motor controller, stepper motor drives and stepper motor body is composed of three parts. Stepper motor controller stepper pulse and direction signal, each made of a pulse, stepper motor-driven stepper motor drives a rotor rotating step angle, that is, step-by-step further. High or low speed stepper motor, or speed, or deceleration, start or stop pulses are entirely dependent on whether the level or frequency. Decide the direction of the signal controller stepper motor clockwise or counterclockwise rotation. Typically, the stepper motor drive circuit from the logic control, power driver circuit, protection circuit and power components. Stepper motor drive controller, once received from the direction of the signal and step pulse, the control circuit on a pre-determined way of the electrical power-phase stepper motor excitation windings of the conduction or cut-off signal. Control circuit output signal power is low, can not provide the necessary stepping motor output power, the need for power amplifier, which is stepper motor driven power drive part. Power stepper motor drive circuit to control the input current winding to form a space forrotating magnetic field excitation, the rotor-driven movement.Protection circuit in the event of short circuit, overload, overheating, such as failure to stop the rapid drive and motor.Motor is usually for the permanent magnet rotor, when the current flows through the stator windings, the stator windings produce a magnetic field vector. The magnetic field will lead to a rotor angle of rotation, making a pair of rotor and stator magnetic field direction of the magnetic field direction. When the stator rotating magnetic field vector from a different angle.Also as the rotor magnetic field to a point of view.An electrical pulse for each input, the motor rotation angle step. Its output and input of the angular displacement is proportional to the pulses, with pulse frequency proportional to speed. Power to change the order of winding, the electrical will be reversed. We can, therefore, control the pulse number, frequency and electrical power windings of each phase to control the order of rotation of stepper motor.Stepper motor types:Permanent magnet (PM). Magnetic generally two-phase stepper, torque and are smaller and generally stepping angle of 7.5 degrees or 15 degrees; put more wind for air-conditioning.Reactive (VR), the domestic general called BF, have a common three-phase reaction, step angle of 1.5 degrees; also have five-phase reaction. Noise, no torque has been set at a large number of out.Hybrid (HB), common two-phase hybrid, five-phase hybrid, three-phase hybrid, four-phase hybrid, two-phase can be common with the four-phase drive, five-phase three-phase must be used with their drives;Two-phase, four-phase hybrid step angle is 1.8 degrees more than a small size, great distance, and low noise;Five-phase hybrid stepping motor is generally 0.72, the motor step angle small, high resolution, but the complexity of drive circuits, wiring problems, such as the 5-phase system of 10 lines.Three-phase hybrid stepping motor step angle of 1.2 degrees, butaccording to the use of 1.8 degrees, the three-phase hybrid stepping motor has a two-phase mixed than the five-phase hybrid more pole will help electric folder symmetric angle, it can be more than two-phase, five-phase high accuracy, the error even smaller, run more smoothly.Stepper motor to maintain torque: stepper motor power means no rotation, the stator locked rotor torque. It is a stepper motor, one of the most important parameters, usually in the low-speed stepper motor torque at the time of close to maintain the torque. As the stepper motor output torque increases with the speed of constant attenuation, the output power also increases with the speed of change, so as to maintain torque on the stepper motor to measure the parameters of one of the most important. For example, when people say that the stepper motor 2N.m, in the absence of special circumstances that means for maintaining the torque of the stepper motor 2N.m.Precision stepper motors: stepper motor step angle accuracy of 3-5%, not cumulative.Start frequency of no-load: the stepper motor in case of no-load to the normal start of the pulse frequency, if the pulse frequency is higher than the value of motor does not start, possible to lose steps or blocking. In the case of the load, start frequency should be lower. If you want to achieve high-speed rotation motor, pulse frequency should be to accelerate the process, that is, the lower frequency to start, and then rose to a certain acceleration of the desired frequency (motor speed from low rise to high-speed).Step angle: that is to send a pulse, the electrical angle corresponding to rotation.Torque positioning: positioning torque stepper motor does not refer to the case of electricity, locked rotor torque stator.Operating frequency: step-by-step stepper motor can run without losing the highest frequency.Subdivision Drive: stepper motor drives the main aim is to weaken or eliminate low-frequency vibration of the stepper motor to improve the accuracyof the motor running. Reduce noise. If the step angle is 1.8 °(full step) the two-phase hybrid stepping motor, if the breakdown of the breakdown of the number of drives for the 8, then the operation of the electrical pulse for each resolution of 0.072 °, the precision of motor can reach or close to 0.225 °, also depends on the breakdown of the breakdown of the drive current control accuracy and other factors, the breakdown of the number of the more difficult the greater the precision of control.步进电机是一种将电脉冲转化为角位移的执行机构。
基于单片机的步进电机无线控制系统外文翻译
附录4:外文文献翻译译文:步进电机应用和控制步进电机是将电脉冲转换成角位移的执行机构。
通俗的讲:当步进电机驱动器接收到脉冲信号,它就驱动步进电机按设定的方向转动一个固定的角即步进角。
你可以控制脉冲的个数来控制角位移量,从而能准确定位;同时你可以通过控制脉冲频率来控制电机转动的速度和加速度,从而达到改变速度的目的。
步进电机不能直接用交直流电源供电,而必须使用专用设备即步进电机驱动器。
步进电机驱动系统的性能,除与电机自身性能有关外,在很大程度上取决于驱动器的好坏。
一个典型的步进电机驱动系统是由步进电机控制器,步进电机驱动器和步进电机三部分组成。
步进电机控制器发出步进脉冲和方向信号,每一个脉冲,步进电机驱动器驱动步进电机转子旋转一个步距角,就是一步。
步进电机转速的高低,加速和减速,启动或停止完全取决脉冲的有无和频率的高低。
控制器的方向信号决定步进电机的正转或者反转。
通常,步进电机驱动器由逻辑控制电路、保护电路、功率驱动电路和电源组成。
当步进电机驱动器接收到来自控制器的方向信号和步进脉冲,控制电路就按照预先设定的电机通电方式产生步进电机各相励磁绕组导通或截止信号。
由于控制电路输出的信号功率很低,不能提供步进电机所需的输出功率,所以必须进行功率放大,这就是步进电机驱动器的功率驱动部分。
功率驱动电路向步进电机控制绕组输入电流,使其励磁形成空间旋转磁场,驱动转子运动。
保护电路在出现短路、过载、等故障时迅速停止驱动器和电机的运行。
电机转子通常是永磁转子,通过定子绕组的电流流时,定子绕组产生的磁场矢量。
会使转子的旋转一定角度,使一对转子的磁场方向和定子的磁场方向一致。
当定子旋转磁场矢量旋转一个角度,转子也随着这个磁场旋转一个角度。
每个输入一个电脉冲,电机的旋转一个角度前进一步。
它的输出角位移和输入脉冲数是成正比的,速度与脉冲频率成正比。
改变绕组通电的顺序,电机就会反转。
因此,我们可以用控制脉冲数,脉冲频率和电机绕组的通电顺序来控制步进电机旋转。
步进电机运动控制系统外文文献翻译中英文
外文文献翻译(含:英文原文及中文译文)文献出处:YH Lee. Stepper motor motion control system design [J]. Equipment Manufacturing Technology, 2015,2(6):31-41.英文原文Stepper motor motion control system designYH LeeAbstractStepper motors are open-loop control elements that convert electrical pulse signals to angular or linear displacements. In the case of non-overload, the rotation speed and stop position of the motor depend only on the frequency and pulse number of the pulse signal, and is not affected by the load change, that is, a pulse signal is applied to the motor, and the motor rotates through a step angle. The existence of this linear relationship, coupled with the fact that the stepper motor has only periodic errors and no cumulative errors, is a feature. It is very simple to use a stepper motor to control the speed and position. Stepper motor speed control is generally to change the frequency of the input stepper motor pulse to achieve stepper motor speed control, because the stepper motor for each pulse to rotate a fixed angle, so that you can control the stepper motor The time interval from one pulse to the next pulse changes the frequency of the pulse. The length of the delay controls the step anglespecifically to change the rotation speed of the motor, thereby realizing the stepping motor speed control. In this design scheme, the internal timer of the A T89C51 microcontroller is used to change the frequency of the CP pulse to realize the control of the rotation speed of the stepper motor to realize the functions of the motor speed adjustment and forward and reverse rotation. The design takes into consideration that the CPU may be disturbed when executing instructions, causing the program to "run away" or enter the "endless loop". Therefore, the watchdog circuit is designed using a microprocessing system monitoring integrated chip manufactured by MAXIM. MAXI813. This article also gives the related hardware block diagram and software flow chart in detail, and has compiled the assembly language program.Keywords: stepper motor single chip microcomputer speed control systemIntroductionStepper motors were first developed by the British in 1920. The invention of the transistor in the late 1950s was also gradually applied to a stepping motor, which made it easier to control the digitization. After continuous improvement, today's stepper motors have been widely used in mechanical systems with high controllability such as high positioning accuracy, high decomposition performance, high responsiveness, and reliability. In the production process, where automation, labor saving, andhigh efficiency are required, we can easily find traces of stepper motors, especially those that emphasize speed, position control, and flexible control applications that require precise command operation. The most. As an actuator, a stepper motor is one of the key products of electromechanical integration and is widely used in various automation control systems. With the development of microelectronics and computer technology, the demand for stepper motors is increasing day by day, and there are applications in various national economic fields. A stepper motor is an actuator that converts an electrical pulse signal into an angular or linear displacement. Stepper motors can be driven directly with digital signals and are very easy to use. The general motor is continuous rotation, while the stepper motor has two basic states of positioning and operation. When there is a pulse input, the stepping motor rotates step by step, and when it is given a pulse signal, it turns a certain angle. The angular displacement of the stepping motor is strictly proportional to the number of input pulses and is synchronized in time with the input pulse. Therefore, as long as the number of input pulses, the frequency, and the phase sequence of the motor windings are controlled, the desired rotation angle can be obtained. Speed and direction of rotation. When there is no pulse input, the air gap magnetic field can keep the rotor in the original position under the excitation of the winding power supply. So it is very suitable for single chip microcomputer control. Stepper motors also havefeatures such as fast start, precise stepping and positioning, and are thus widely used in CNC machine tools, plotters, printers, and optical instruments. Stepping motors have become the third category of motors except for DC motors and AC motors. Traditional electric motors, as electromechanical energy conversion devices, play a key role in human production and life into the electrification process. The stepper motor can be used as a special motor for control, and it is widely used in various open-loop control because it has no accumulated error (accuracy is 100%). Now more commonly used stepper motors include reactive stepper motors (VR), permanent magnet stepper motors (PM), hybrid stepper motors (HB), and single-phase stepper motors. Permanent-magnet type stepping motor is generally two-phase, small torque and volume, step angle is generally 7.5 degrees or 15 degrees; Reactive stepping motor is generally three-phase, can achieve large torque output, stepping The angle is generally 1.5 degrees, but the noise and vibration are large. The rotor of the reactive stepper motor is magnetically routed from a soft magnetic material, and the stator has a multi-phase excitation winding, which generates torque using a change in the magnetic permeability. Hybrid stepping motor refers to the advantage of mixing permanent magnet type and reactive type. It is divided into two phases and five phases: the two-phase step angle is generally 1.8 degrees and the five-phase step angle is generally 0.72 degrees. This type of steppermotor is the most widely used and is also the stepper motor used in this subdivision drive scheme.1 stepper motor overview1. 1 stepper motor features:1) The accuracy of a typical stepper motor is 3-5% of the step angle and does not accumulate. 2) The allowable temperature of the stepper motor is high. Excessively high temperature of the stepping motor first demagnetizes the magnetic material of the motor, resulting in a drop in torque and even loss of synchronism. Therefore, the maximum temperature allowed for the appearance of the motor should depend on the demagnetization point of the magnetic material of different motors; generally, the demagnetization of the magnetic material. The points are all above 130 degrees Celsius, and some are even up to 200 degrees Celsius. Therefore, the external temperature of the stepper motor is completely normal at 80-90 degrees Celsius. 3) The torque of the stepper motor will decrease as the rotation speed increases. When the stepper motor rotates, the inductance of each phase winding of the motor will form a counter electromotive force; the higher the frequency, the greater the counter electromotive force. Under its effect, the motor's phase current decreases as the frequency (or speed) increases, causing the torque to drop. 4) The stepping motor can run normally at low speed, but it cannot start if it is higher than a certain speed, accompanied by howling. The stepper motorhas a technical parameter: No-load starting frequency, that is the pulse frequency that the stepping motor can start normally under no-load conditions. If the pulse frequency is higher than this value, the motor cannot start normally, and step loss or stall may occur. In the case of load, the starting frequency should be lower. If the motor is to be rotated at a high speed, the pulse frequency should have an acceleration process, that is, the starting frequency is low, and then it is increased to a desired high frequency (motor speed is raised from low speed to high speed) at a certain acceleration. TC \* MERGEFORMA T1. 2 working principle of stepping motorA stepper motor is a type of motor that is controlled by an electrical pulse and converts the electrical pulse signal into a phase-shifted motor whose mechanical displacement and rotational speed are proportional to the number of pulses and the pulse frequency of the input motor winding. Each pulse signal can be stepped The feed motor rotates at a fixed angle. The number of pulses determines the total angle of rotation. The frequency of the pulse determines the speed of the motor. When the stepper receives a pulse signal, it drives the stepper motor to rotate in the set direction. At a fixed angle (called "step angle"), its rotation is performed step by step at a fixed angle. By controlling the number of pulses to control the angular displacement, so as to achieve the purpose of accurate positioning; At the same time, by controlling the pulse frequencyto control the speed and acceleration of the motor rotation, so as to achieve the purpose of speed control.2 Basic requirements for designStudy the characteristics, working principle, and specific speed regulation principle of stepper motor. TC \* MERGEFORMA T Basic requirements The stepper motor uses a three-phase stepper motor with a power of 1W. When the speed is in the range of 0 to 1000r/min, the maximum accuracy is 2%. To basically complete the graduation design, the stepper motor can perform precise speed control, positive and negative rotation, and it can not lose step when starting. Basically, there is no Oscillation, can complete the complete hardware circuit diagram, software design.3 Argumentation of the plan3.1 Determination of control methodsAlthough the stepper motor control is a relatively accurate, open-loop stepper motor control system has the advantages of low cost, simple, convenient control, etc., in the open-loop system of the stepper motor using the microcontroller, the frequency of the CP pulse of the control system or change The cycle is actually controlling the speed of the stepper motor. There are two ways the system can achieve stepper motor speed control. One is delay, the other is timing. The delay method is to call a delay subroutine after each commutation. After the delay isover, the commutation is executed again. In this way, CP pulses or commutation cycles with a certain frequency can be issued. The delay time of the delay subroutine and the time used by the commutation program are the cycles of the CP pulse. This method is simple, uses less resources, and is implemented by software. Different subroutines can be called to achieve different speeds. However, it takes a long time to process the CPU and cannot handle other tasks at runtime. Therefore, it is only suitable for a simpler control process. The timing method is to use the timer timing function in the microcontroller system to generate an arbitrary period of the timing signal, so that the period of the system output CP pulse can be conveniently controlled. When the timer is started, the timer counts up the system and its cycle starting from the loaded initial value. When the timer overflows, the timer generates an interrupt and the system transfers to execute the timer interrupt subroutine. The motor commutation subroutine is placed in the timer interrupt service routine. The timer interrupt is once and the motor is reversed once to achieve motor speed control. Since there is a certain time interval from the start of restarting the timer to the timer application interruption, the timing time is increased. In order to reduce this timing error and achieve accurate timing, it is necessary to make appropriate adjustments to the initial value of reloading counts. . The initial value of adjusted reloading mainly considers two factors and one is the time required to interrupt theresponse. The second is the time occupied by reloading the initial value instruction, including other instructions that interrupt the service program before reloading the initial value. After these two factors are combined, the correction amount of the reload count initial value takes 8 machine cycles, that is, the timing time is shortened by 8 machine cycles. When using the timer interrupt to control the motor shift, it is actually changing the size of the timer load value. In the control process, a discrete approach is used to approximate the ideal speed curve. In order to reduce the time for calculating the load value in each step, the load value required for the speed of each discrete point is fixed in the ROM of the system when the system is designed. The system uses the table look-up method to find the required load value in the system. Significantly reduce the time spent on CPU and improve the response speed of the system. Most stepper motor motion control systems are designed to run in an open-loop state, because the cost is low, and the position control inherent in the motion control technology can be provided without feedback. However, in some applications, more reliability, security, or product quality assurance is required. Therefore, closed-loop control is also an option. Here are some methods for achieving closed-loop control of stepper motors: 1) Step-by-step confirmation, This is the simplest displacement control, using a low-value optical encoder to calculate the amount of step movement. A simple loop compares the stepper motor with the commandverification and verifies that the stepper motor moves to the expected position; 2) Back-EMF, a sensorless detection method, uses a stepper motor's back EMF (eleCtromotiveCe, emf) signal , Measure and control speed. When the back-EMF voltage drops to the monitoring detection level, the closed-loop control is changed to the standard open-loop to complete the final displacement movement; 3) Full-servo control refers to the full-time use of feedback devices for stepper motors - encoders, decoding , or other feedback sensors to more accurately control the stepper motor displacement and torque. Other methods include a variety of different back-EMF control motor parameter measurements and software techniques that some manufacturers use. Here, the stepper drive monitors and measures the motor coils and uses voltage current information to increase the stepper motor control. Positive damping uses this information to block the speed of vibration, producing more usable torque output and reducing torque-induced mechanical vibration losses. No encoder installation monitoring uses information to detect the loss of synchronous speed. Conventional stepper motor control usually employs feedback devices and non-sensing methods, and is an effective method to implement a sports application with safety requirements, dangerous conditions or high accuracy requirements. Most stepper motor-based systems typically operate in an open-loop state, which provides a low-cost solution. In fact, stepper systems can improve the performanceof displacement control without feedback. However, when the stepper motor is running in open loop, there may be a simultaneous loss between the command pace and the actual step. Closed-loop control, which is part of traditional step control, can effectively provide higher reliability, safety, or product quality. In these stepper systems, the closed loop of the feedback device or indirect parametric sensing method can correct or control out-of-step, monitor motor stagnation, and ensure greater available torque output. Recently, closed-loop control (CLC) of stepper motors can also help implement smart distributed motion architectures. However, there is a risk of out-of-step operation in open-loop operation, which will result in positioning errors. However, compared to encoders used in servo systems, closed-loop stepper motors use encoders that are less costly. Therefore, closed-loop control is selected.3.2 Determination of Drive ModeThere are generally two methods for driving a stepping motor. One is directly driven by the CPU. This method is generally not suitable because the output current pulse of the CPU is extremely small and it cannot sufficiently rotate the stepping motor. One is indirect driving by the CPU, which is to amplify the signal output from the CPU, and then directly drive or indirectly drive the stepper motor through photoelectric isolation. This method is relatively safe and reliable. The solid design should use a CPU to drive the stepper motor indirectly. Thetachogenerator of the encoder is also used as the speed measurement tool. Because the closed-loop control is selected, there must be feedback components. There are generally two types of feedback components. One is the coaxial tachometer generator, and the speed of the stepping motor is fed back. Back, and then through the display and stepper motor adjustment; Another is through the optical coaxial encoder to the stepper motor speed feedback back to the stepper motor to adjust; compared to the latter, the latter The design is relatively simple, inexpensive, safe and reliable, and less polluting. The latter is generally used for solids, and photoelectric crumblers are used as feedback components.3. 3 Selection of Drive CircuitThere are many kinds of driving motors for stepping motors, but the most common ones are single voltage driving, dual voltage driving, chopper driving, subdivision control driving and so on. Single-voltage driving is the simplest driving circuit in stepper motor control. It is essentially a single-phase inverter. Its greatest feature is its simple structure, because of its low work efficiency, especially its prominent features at high frequencies. Its external resistor R consumes a considerable amount of heat, which affects the stability of the circuit. This type of drive is generally used only in the drive circuit of a low-power stepper motor. Dual-voltage driving is generally driven by two power supply voltages. Since these two power supplies are one highvoltage and one low voltage, they are also called high and low voltage driving circuits. The disadvantage of the dual-voltage driving circuit is that the valley point appears in the current at the high-low voltage connection, which inevitably causes the torque to drop at the valley point. Not suitable for normal operation of the motor. For the chopper circuit drive, this disadvantage can be overcome and the efficiency of the stepper motor can also be improved. Therefore, it is a good driver circuit from the standpoint of improving efficiency. It can use a higher power supply voltage and does not require an external resistor to limit the rated current and reduce the time constant. However, due to the sawtooth fluctuations at the top of the waveform, large electromagnetic noise is generated. The subdivision drive is powered by a pulse voltage. For a voltage pulse, the rotor can rotate one step. Generally, according to the voltage pulse distribution method, each phase winding of the stepping motor will alternately switch, and the rotor of the stepping motor can be fixed. Rotate. The subdivided control circuit is generally divided into two types. One is to use a linear analog power amplifier to obtain a staircase current. This method is simple but inefficient. The other method is to use a single-chip microcomputer to obtain the step current by using the method of pulse width modulation. This method requires complex calculations to make the substepped step angles uniform. However, due to the fact that the design of the stepper motor requires a relatively wide range ofhigh-speed adjustments, the drive chip 8713 should be used to drive the motor and the speed of the stepper motor must be controlled by software.中文译文步进电机运动控制系统设计作者:YH Lee摘要步进电机是将电脉冲信号转变为角位移或线位移的开环控制元件。
步进电机和伺服电机的系统控制-----英文翻译正文
英文专业资料翻译英文资料题目Step Motor & Servo MotorSystems and Controls英文资料来源Motion and Control中文译文题目步进电机和伺服电机的系统控制专业自动化姓名学号指导教师二OO八年六月十三日Step Motor&Servo Motor Systems and Controls WITH SUPPORT SOFTWARE, THERE’S NO MORE GUESS WORK Motion Architect® Software Does the Work for You... Configure ,Diagnose, Debug Compumotor’s M otion Architect is a Mic rosoft® Windows™-based software development tool for 6000Series products that allows you to automatically generate commented setup code, edit and execute motion control programs, and create a custom operator test panel. The heart of Motion Architect is the shell, which provides an integrated environment to access the following modules.• System Configurator—This module prompts you to fill in all pertinent set-up information to initiate motion. Configurable to the specific 6000 Series product that is selected, the information is then used to generate actual 6000-language code that is the beginning of your program.• Program Editor—This module allows you to edit code. It also has the commands available through ―Help‖ menus. A user’s gui de is provided on disk.• Terminal Emulator—This module allows you to interact directly with the 6000 product. ―Help‖ is again available with all commands and their definitions available for reference.• Test Panel—You can simulate your programs, debug programs, and check for program flow using this module.Because Its Windows, You Already Know How to Use ItMotion Architect® has been designed for use with all 6000 Series products—for both servo and stepper technologies. The versatility of Windows and the 6000 Series language allow you to solve applications ranging from the very simple to the complex.Motion Architect comes standard with each of the 6000 Series products and is a tool that makes using these controllers even more simple—shortening the project development time considerably. A value-added feature of Motion Architect, when used with the 6000 Servo Controllers, is its tuning aide. This additional module allows you to graphically display a variety of move parameters and see how these parameters change based on tuning values.Using Motion Architect, you can open multiple windows at once. For example, both the Program Editor and Terminal Emulator windows can be opened to run the program, get information, and then make changes to the program.On-line help is available throughout Motion Architect, including interactive access to the contents of the Compumotor 6000 Series Software Reference Guide.SOLVING APPLICATIONS FROM SIMPLETO COMPLEXServo Control is Yours with Servo Tuner SoftwareCompumotor combines the 6000 Series servo controllers with Servo Tuner software. The Servo Tuner is an add-on module that expands and enhances the capabilities of Motion Architect®.Motion Architect and the Servo Tuner combine to provide graphical feedback ofreal-time motion information and provide an easy environment for setting tuning gains and related systemparameters as well as providing file operations to save and recall tuning sessions.Draw Your Own Motion Control Solutions with Motion Toolbox Software Motion Tool box™ is an extensive library of LabVIEW® virtual instruments (VIs) for icon-based programming of Compumotor’s 6000 Series motion controllers.When using Motion Toolbox with LabVIEW, programming of the 6000 Series controller is accomplished by linking graphic icons, or VIs, together to form a block diagram. Motion Toolbox’s has a library of more than 150 command,status, and example VIs. All command and status VIs include LabVIEW source diagrams so you can modify them, if necessary, to suit your particular needs. Motion Toolbox als user manual to help you gut up and running quickly.comprehensiveM Software for Computer-Aided Motion Applications CompuCAM is a Windows-based programming package that imports geometry from CAD programs, plotter files, or NC programs and generates 6000 code compatible with Compumotor’s 6000 Series motion controllers. Available for purchase from Compumotor, CompuCAM is an add-on module which is invoked as a utility from the menu bar of Motion Architect.From CompuCAM, run your CAD software package. Once a drawing is created, save it as either a DXF file, HP-GL plot file or G-code NC program. This geometry is then imported into CompuCAM where the 6000 code is generated. After generating the program, you may use Motion Architect functions such as editing or downloading the code for execution.Motion Builder Software for Easy Programming of the 6000 SeriesMotion Builder revolutionizes motion control programming. This innovative software allows programmers to program in a way they are familiar with—a flowchart-style method. Motion Builder decreases the learning curve and makes motion control programming easy.Motion Builder is a Microsoft Windows-based graphical development environment which allows expert and novice programmers to easily program the 6000 Series products without learning a new programming language. Simply drag and drop visual icons that represent the motion functions you want to perform.Motion Builder is a complete application development environment. In addition tovisually programming the 6000 Series products, users may configure, debug, download, and execute the motion program.SERVO VERSUS STEPPER... WHAT YOU NEEDTO KNOWMotor Types and Their ApplicationsThe following section will give you some idea of the applications that are particularly appropriate for each motor type, together with certain applications that are best avoided. It should be stressed that there is a wide range of applications which can be equally well met by more than one motor type, and the choice will tend to be dictated by customer preference, previous experience or compatibility with existing equipment.A helpful tool for selecting the proper motor for your application is Compumotor’s Motor Sizing and Selection software package. Using this software, users can easily identify the appropriate motor size and type.High torque, low speedcontinuous duty applications are appropriate to the step motor. At low speeds it is very efficient in terms of torque output relative to both size and input power. Microstepping can be used to improve smoothness in lowspeed applications such as a metering pump drive for very accurate flow control.High torque, high speedcontinuous duty applications suit the servo motor, and in fact a step motor should be avoided in such applications because the high-speed losses can cause excessive motor heating.Short, rapid, repetitive movesare the natural domain of the stepper due to its high torque at low speeds, goodtorque-to-inertia ratio and lack of commutation problems. The brushes of the DC motor can limit its potential for frequent starts, stops and direction changes.Low speed, high smoothness application sare appropriate for microstepping or direct drive servos.Applications in hazardous environmentsor in a vacuum may not be able to use a brushed motor. Either a stepper or a brushless motor is called for, depending on the demands of the load. Bear in mind that heat dissipation may be a problem in a vacuum when the loads are excessive.SELECTING THE MOTOR THAT SUITS YOURAPPLICATIONIntroductionMotion control, in its widest sense, could relate to anything from a welding robot to the hydraulic system in a mobile crane. In the field of Electronic Motion Control, we are primarily concerned with systems falling within a limited power range, typically up to about 10HP (7KW), and requiring precision in one or more aspects. This may involve accurate control of distance or speed, very often both, and sometimes other parameters such as torque or acceleration rate. In the case of the two examples given, the welding robot requires precise control of both speed and distance; the crane hydraulic system uses the driver as the feedback system so its accuracy varies with the skill of the operator. This wouldn’t be considered a motion control system in the strict sense of the term.Our standard motion control system consists of three basic elements:Fig. 1 Elements of motion control systemThe motor. This may be a stepper motor (either rotary or linear), a DC brush motor or a brushless servo motor. The motor needs to be fitted with some kind of feedback device unless it is a stepper motor.Fig. 2 shows a system complete with feedback to control motor speed. Such a system is known as a closed-loop velocity servo system.Fig. 2 Typical closed loop (velocity) servo systemThe drive. This is an electronic power amplifier thatdelivers the power to operate the motor in response to low-level control signals. In general, the drive will be specifically designed to operate with a particular motor type –you can’t use a stepper drive to operate a DC brush motor, for instance.Application Areas of Motor TypesStepper MotorsStepper Motor BenefitsStepper motors have the following benefits:• Low cost• Ruggedness• Simplicity in construction• High reliabi lity• No maintenance• Wide acceptance• No tweaking to stabilize• No feedback components are needed• They work in just about any environment• Inherently more failsafe than servo motors.There is virtually no conceivable failure within the stepper drive module that could cause the motor to run away. Stepper motors are simple to drive and control in an open-loop configuration. They only require four leads. They provide excellent torque at low speeds, up to 5 times the continuous torque of a brush motor of the same frame size or double the torque of the equivalent brushless motor. This often eliminates the need for a gearbox. A stepper-driven-system is inherently stiff, with known limits to the dynamic position error.Stepper Motor DisadvantagesStepper motors have the following disadvantages:• Resonance effects and relatively long settlingtimes• Rough performance at low speed unless amicrostep drive is used• Liability to undetected position loss as a result ofoperating open-loop• They consume curren t regardless of loadconditions and therefore tend to run hot• Losses at speed are relatively high and can causeexcessive heating, and they are frequently noisy(especially at high speeds).• They can exhibit lag-lead oscillation, which isdifficult to damp. There is a limit to their availablesize, and positioning accuracy relies on themechanics (e.g., ballscrew accuracy). Many ofthese drawbacks can be overcome by the use ofa closed-loop control scheme.Note: The Compumotor Zeta Series minimizes orreduces many of these different stepper motor disadvantages.There are three main stepper motor types:• Permanent Magnet (P.M.) Motors• Variable Reluctance (V.R.) Motors• Hybrid MotorsWhen the motor is driven in its full-step mode, energizing two winding s or ―phases‖ at atime (see Fig. 1.8), the torque available on each step will be the same (subject to very small variations in the motor and drive characteristics). In the half-step mode, we are alternately energizing two phases and then only one as shown in Fig. 1.9. Assuming the drive delivers the same winding current in each case, this will cause greater torque to be produced when there are two windings energized. In other words, alternate steps will be strong and weak. This does not represent a major deterrent to motor performance—the available torque is obviously limited by the weaker step, but there will be a significant improvement in low-speed smoothness over the full-step mode.Clearly, we would like to produce approximately equal torque on every step, and this torque should be at the level of the stronger step. We can achieve this by using a higher current level when there is only one winding energized. This does not over dissipate the motor because the manufacturer’s current rating assumes two pha ses to be energized the current rating is based on the allowable case temperature). With only one phase energized, the same total power will be dissipated if the current is increased by 40%. Using this higher current in the one-phase-on state produces approximately equal torque on alternate steps (see Fig. 1.10).Fig. 1.8 Full step current, 2-phase onFig. 1.9 Half step currentFig. 1.10 Half step current, profiledWe have seen that energizing both phases with equal currents produces an intermediate step position half-way between the one-phase-on positions. If the two phase currents are unequal, the rotor position will be shifted towards the stronger pole. This effect is utilized in the microstepping drive, which subdivides the basic motor step by proportioning the current in the two windings. In this way, the step size is reduced and the low-speed smoothness is dramatically improved. High-resolution microstep drives divide the full motor step into as many as 500 microsteps, giving 100,000 steps per revolution. In this situation, the current pattern in the windings closely resembles two sine waves with a 90°phase shift between them (see Fig. 1.11). The motor is now being driven very much as though it is a conventional AC synchronous motor. In fact, the stepper motor can be driven in this way from a 60 Hz-US (50Hz-Europe) sine wave source by including a capacitor in series with one phase. It will rotate at 72 rpm.Fig. 1.11 Phase currents in microstep modeStandard 200-Step Hybrid MotorThe standard stepper motor operates in the same way as our simple model, but has a greater number of teeth on the rotor and stator, giving a smaller basic step size. The rotor is in two sections as before, but has 50 teeth on each section. The half-tooth displacement between the two sections is retained. The stator has 8 poles each with 5 teeth, making a total of 40 teeth (see Fig. 1.12).Fig. 1.12 200-step hybrid motorIf we imagine that a tooth is placed in each of the gaps between the stator poles, there would be a total of 48 teeth, two less than the number of rotor teeth. So if rotor and stator teeth are aligned at 12 o’clock, they will also be aligned at 6 o’clock. At 3 o’clock and 9 o’clock the teeth will be misaligned. However, due to the displacement between the sets of rotor teeth, alignment will occur at 3 o’clock and 9 o’clock at the other end of the rotor.The windings are arranged in sets of four, and wound such that diametrically-opposite poles are the same. So referring to Fig. 1.12, the north poles at 12 a nd 6 o’clock attract the south-pole teeth at the front of the rotor; the south poles at 3 and 9 o’clock attract the north-pole teeth at the back. By switching current to the second set of coils, the stator field pattern rotates through 45°. However, to align with this new field, the rotor only has to turn through 1.8°. This is equivalent to one quarter of a tooth pitch on the rotor, giving 200 full steps per revolution.Note that there are as many detent positions as there are full steps per rev, normally 200. The detent positions correspond with rotor teeth being fully aligned with stator teeth. When power is applied to a stepper drive, it is usual for it to energize in the ―zero phase‖ state in which there is current in both sets of windings. The resulting rotor position does not correspond with a natural detent position, so an unloaded motor will always move by at least one half step at power-on. Of course, if the system was turned off other than in the zero phase state, or the motor is moved in the meantime, a greater movement may be seen at power-up.Another point to remember is that for a given current pattern in the windings, there are as many stable positions as there are rotor teeth (50 for a 200-step motor). If a motor isde-synchronized, the resulting positional error will always be a whole number of rotor teeth or a multiple of 7.2°. A motor cannot ―miss‖ individual steps – position errors of one or two steps must be due to noise, spurious step pulses or a controller fault.Fig. 2.19 Digital servo driveDigital Servo Drive OperationFig. 2.19 shows the components of a digital drive for a servo motor. All the main control functions are carried out by the microprocessor, which drives a D-to-A convertor to produce an analog torque demand signal. From this point on, the drive is very much like an analog servo amplifier.Feedback information is derived from an encoder attached to the motor shaft. The encoder generates a pulse stream from which the processor can determine the distance travelled, and by calculating the pulse frequency it is possible to measure velocity.The digital drive performs the same operations as its analog counterpart, but does so by solving a series of equations. The microprocessor is programmed with a mathematical model (or ―algorithm‖) of the equivalent analog system. This model predicts the behavior of the system. In response to a given input demand and output position. It also takes into account additional information like the output velocity, the rate of change of the input and the various tuning settings.To solve all the equations takes a finite amount of time, even with a fast processor – this time is typically between 100ms and 2ms. During this time, the torque demand must remain constant at its previously-calculated value and there will be no response to a change at the input or output. This ―update time‖ therefore becomes a critical factor in the performance of a digital servo and in a high-performance system it must be kept to a minimum.The tuning of a digital servo is performed either by pushbuttons or by sending numerical data from a computer or terminal. No potentiometer adjustments are involved. The tuning data is used to set various coefficients in the servo algorithm and hence determines the behavior of the system. Even if the tuning is carried out using pushbuttons, the final values can be uploaded to a terminal to allow easy repetition.In some applications, the load inertia varies between wide limits – think of an arm robot that starts off unloaded and later carries a heavy load at full extension. The change in inertia may well be a factor of 20 or more, and such a change requires that the drive isre-tuned to maintain stable performance. This is simply achieved by sending the new tuning values at the appropriate point in the operating cycle.步进电机和伺服电机的系统控制只要有软件的支持,这里将不再有猜测性的工作。
步进电机-英文资料及翻译(Stepping Motor Types)
Stepping Motor TypesIntroductionStepping motors come in two varieties, permanent magnet and variable reluctance (there are also hybrid motors, which are indistinguishable from permanent magnet motors from the controller's point of view). Lacking a label on the motor, you can generally tell the two apart by feel when no power is applied. Permanent magnet motors tend to "cog" as you twist the rotor with your fingers, while variable reluctance motors almost spin freely (although they may cog slightly because of residual magnetization in the rotor). You can also distinguish between the two varieties with an ohmmeter. Variable reluctance motors usually have three (sometimes four) windings, with a common return, while permanent magnet motors usually have two independent windings, with or without center taps. Center-tapped windings are used in unipolar permanent magnet motors.Stepping motors come in a wide range of angular resolution. The coarsest motors typically turn 90 degrees per step, while high resolution permanent magnet motors are commonly able to handle 1.8 or even 0.72 degrees per step. With an appropriate controller, most permanent magnet and hybrid motors can be run in half-steps, and some controllers can handle smaller fractional steps or microsteps.For both permanent magnet and variable reluctance stepping motors, if just one winding of the motor is energised, the rotor (under no load) will snap to a fixed angle and then hold that angle until the torque exceeds the holding torque of the motor, at which point, the rotor will turn, trying to hold at each successive equilibrium point.Variable Reluctance MotorsFigure 1.1If your motor has three windings, typically connected as shown in the schematic diagram in Figure 1.1, with one terminal common to all windings, it is most likely a variable reluctance stepping motor. In use, the common wire typically goes to the positive supply and the windings are energized in sequence.The cross section shown in Figure 1.1 is of 30 degree per step variable reluctance motor. The rotor in this motor has 4 teeth and the stator has 6 poles, with each winding wrapped around two opposite poles. With winding number 1 energised, the rotor teeth marked X are attracted to this winding's poles. If the current through winding 1 is turned off and winding 2 is turned on, the rotor will rotate 30 degrees clockwise so that the poles marked Y line up with the poles marked 2.To rotate this motor continuously, we just apply power to the 3 windings in sequence. Assuming positive logic, where a 1 means turning on the current through a motor winding, the following control sequence will spin the motor illustrated in Figure 1.1 clockwise 24 steps or 2 revolutions:Winding 1 1001001001001001001001001Winding 2 0100100100100100100100100Winding 3 0010010010010010010010010 time --->The section of this tutorial on Mid-Level Control provides details on methods for generating such sequences of control signals, while the section on Control Circuits discusses the power switching circuitry needed to drive the motor windings from such control sequences.There are also variable reluctance stepping motors with 4 and 5 windings, requiring 5 or 6 wires. The principle for driving these motors is the same as that for the three winding variety, but it becomes important to work out the correct order to energise the windings to make the motor step nicely.The motor geometry illustrated in Figure 1.1, giving 30 degrees per step, uses the fewest number of rotor teeth and stator poles that performs satisfactorily. Using more motor poles and more rotor teeth allows construction of motors with smaller step angle. Toothed faces on each pole and a correspondingly finely toothed rotor allows for step angles as small as a few degrees.Unipolar MotorsFigure 1.2Unipolar stepping motors, both Permanent magnet and hybrid stepping motors with 5 or 6 wires are usually wired as shown in the schematic in Figure 1.2, with a center tap on each of two windings. In use, the center taps of the windings are typically wired to the positive supply, and the two ends of each winding are alternately grounded to reverse the direction of the field provided by that winding.The motor cross section shown in Figure 1.2 is of a 30 degree per step permanent magnet or hybrid motor -- the difference between these two motor types is not relevant at this level of abstraction. Motor winding number 1 is distributed between the top and bottom stator pole, while motor winding number 2 is distributed between the left and right motor poles. The rotor is a permanent magnet with 6 poles, 3 south and 3 north, arranged around its circumfrence.For higher angular resolutions, the rotor must have proportionally more poles. The 30 degree per step motor in the figure is one of the most common permanent magnet motor designs, although 15 and 7.5 degree per step motors are widely available. Permanent magnet motors with resolutions as good as 1.8 degrees per step are made, and hybrid motors are routinely built with 3.6 and 1.8 degrees per step, with resolutions as fine as 0.72 degrees per step available.As shown in the figure, the current flowing from the center tap of winding 1 to terminal a causes the top stator pole to be a north pole while the bottom stator pole is a south pole. This attracts the rotor into the position shown. If the power to winding 1 is removed and winding 2 is energised, the rotor will turn 30 degrees, or one step.To rotate the motor continuously, we just apply power to the two windings in sequence. Assuming positive logic, where a 1 means turning on the current through a motor winding, the following two control sequences will spin the motor illustrated in Figure 1.2 clockwise 24 steps or 2 revolutions:Winding 1a 1000100010001000100010001Winding 1b 0010001000100010001000100Winding 2a 0100010001000100010001000Winding 2b 0001000100010001000100010 time --->Winding 1a 1100110011001100110011001Winding 1b 0011001100110011001100110Winding 2a 0110011001100110011001100Winding 2b 1001100110011001100110011 time --->Note that the two halves of each winding are never energized at the same time. Both sequences shown above will rotate a permanent magnet one step at a time. The top sequence only powers one winding at a time, as illustrated in the figure above; thus, it uses less power. The bottom sequence involves powering two windings at a time and generally produces a torque about 1.4 times greater than the top sequence while using twice as much power.The section of this tutorial on Mid-Level Control provides details on methods for generating such sequences of control signals, while the section on Control Circuits discusses the power switching circuitry needed to drive the motor windings from such control sequences.The step positions produced by the two sequences above are not the same; as a result, combining the two sequences allows half stepping, with the motor stopping alternately at the positions indicated by one or the other sequence. The combined sequence is as follows:Winding 1a 11000001110000011100000111Winding 1b 00011100000111000001110000Winding 2a 01110000011100000111000001Winding 2b 00000111000001110000011100time --->Bipolar MotorsFigure 1.3Bipolar permanent magnet and hybrid motors are constructed with exactly the same mechanism as is used on unipolar motors, but the two windings are wired more simply, with no center taps. Thus, the motor itself is simpler but the drive circuitry needed to reverse the polarity of each pair of motor poles is more complex. The schematic in Figure 1.3 shows how such a motor is wired, while the motor cross section shown here is exactly the same as the cross section shown in Figure 1.2.The drive circuitry for such a motor requires an H-bridge control circuit for each winding; these are discussed in more detail in the section on Control Circuits. Briefly, an H-bridge allows the polarity of the power applied to each end of each winding to be controlled independently. The control sequences for single stepping such a motor are shown below, using + and - symbols to indicate the polarity of the power applied to each motor terminal:Terminal 1a +---+---+---+--- ++--++--++--++--Terminal 1b --+---+---+---+- --++--++--++--++Terminal 2a -+---+---+---+-- -++--++--++--++-Terminal 2b ---+---+---+---+ +--++--++--++--+ time --->Note that these sequences are identical to those for a unipolar permanent magnet motor, at an abstract level, and that above the level of the H-bridge power switching electronics, the control systems for the two types of motor can be identical.Note that many full H-bridge driver chips have one control input to enable the output and another to control the direction. Given two such bridge chips, one per winding, the following control sequences will spin the motor identically to the control sequences given above:Enable 1 1010101010101010 1111111111111111Direction 1 1x0x1x0x1x0x1x0x 1100110011001100Enable 2 0101010101010101 1111111111111111Direction 2 x1x0x1x0x1x0x1x0 0110011001100110 time --->To distinguish a bipolar permanent magnet motor from other 4 wire motors, measure the resistances between the different terminals. It is worth noting that some permanent magnet stepping motors have 4 independent windings, organized as two sets of two. Within each set, if the two windings are wired in series, the result can be used as a high voltage bipolar motor. If they are wired in parallel, the result can be used as a low voltage bipolar motor. If they are wired in series with a center tap, the result can be used as a low voltage unipolar motor. Bifilar MotorsBifilar windings on a stepping motor are applied to the same rotor and stator geometry as a bipolar motor, but instead of winding each coil in the stator with a single wire, two wires are wound in parallel with each other. As a result, the motor has 8 wires, not four.In practice, motors with bifilar windings are always powered as either unipolar or bipolar motors. Figure 1.4 shows the alternative connections to the windings of such a motor.Figure 1.4To use a bifilar motor as a unipolar motor, the two wires of each winding are connected in series and the point of connection is used as a center-tap. Winding 1 in Figure 1.4 is shown connected this way.To use a bifilar motor as a bipolar motor, the two wires of each winding are connected either in parallel or in series. Winding 2 in Figure 1.4 is shown with a parallel connection; this allows low voltage high-current operation. Winding 1 in Figure 1.4 is shown with a series connection; if the center tap is ignored, this allows operation at a higher voltage and lower current than would be used with the windings in parallel.It should be noted that essentially all 6-wire motors sold for bipolar use are actually wound using bifilar windings, so that the external connection that serves as a center tap is actually connected as shown for winding 1 in Figure 1.4. Naturally, therefore, any unipolar motor may be used as a bipolar motor at twice the rated voltage and half the rated current as is given on the nameplate.The question of the correct operating voltage for a bipolar motor run as a unipolar motor, or for a bifilar motor with the motor windings in series is not as trivial as it might first appear. There are three issues: The current carrying capacity of the wire, cooling the motor, and avoiding driving the motor's magnetic circuits into saturation. Thermal considerations suggest that, if the windings are wired in series, the voltage should only be raised by the square root of 2. The magnetic field in the motor depends on the number of ampere turns; when the two half-windings are run in series, the number of turns is doubled, but because a well-designed motor has magnetic circuits that are close to saturation when the motor is run at its rated voltage and current, increasing the number of ampere-turns does not make the field any stronger. Therefore, when a motor is run with the two half-windings in series, the current should be halved in order to avoid saturation; or, in other words, the voltage across the motor winding should be the same as it was.For those who salvage old motors, finding an 8-wire motor poses a challenge! Which of the 8 wires is which? It is not hard to figure this out using an ohm meter, an AC volt meter, and a low voltage AC source. First, use the ohm meter to identify the motor leads that are connected to each other through the motor windings. Then, connect a low-voltage AC source to one of these windings. The AC voltage should be below the advertised operating voltage of the motor; voltages under 1 volt are recommended. The geometry of the magnetic circuits of the motor guarantees that the two wires of a bifilar winding will be strongly coupled for AC signals, while there should be almost no coupling to the other two wires. Therefore, probing with an AC volt meter should disclose which of the other three windings is paired to the winding under power. Multiphase MotorsFigure 1.5A less common class of permanent magnet or hybrid stepping motor is wired with all windings of the motor in a cyclic series, with one tap between each pair ofwindings in the cycle, or with only one end of each motor winding exposed while the other ends of each winding are tied together to an inaccessible internal connection. In the context of 3-phase motors, these configurations would be described as Delta and Y configurations, but they are also used with 5-phase motors, as illustrated in Figure 1.5. Some multiphase motors expose all ends of all motor windings, leaving it to the user to decide between the Delta and Y configurations, or alternatively, allowing each winding to be driven independently.Control of either one of these multiphase motors in either the Delta or Y configuration requires 1/2 of an H-bridge for each motor terminal. It is noteworthy that 5-phase motors have the potential of delivering more torque from a given package size because all or all but one of the motor windings are energised at every point in the drive cycle. Some 5-phase motors have high resolutions on the order of 0.72 degrees per step (500 steps per revolution).Many automotive alternators are built using a 3-phase hybrid geometry with either a permanent magnet rotor or an electromagnet rotor powered through a pair of slip-rings. These have been successfully used as stepping motors in some heavy duty industrial applications; step angles of 10 degrees per step have been reported.With a 5-phase motor, there are 10 steps per repeat in the stepping cycle, as shown below:Terminal 1 +++-----+++++-----++Terminal 2 --+++++-----+++++---Terminal 3 +-----+++++-----++++Terminal 4 +++++-----+++++-----Terminal 5 ----+++++-----+++++-time --->With a 3-phase motor, there are 6 steps per repeat in the stepping cycle, as shown below:Terminal 1 +++---+++---Terminal 2 --+++---+++-Terminal 3 +---+++---++time --->Here, as in the bipolar case, each terminal is shown as being either connected to the positive or negative bus of the motor power system. Note that, at each step, only one terminal changes polarity. This change removes the power from one winding attached to that terminal (because both terminals of the winding in question are of the same polarity) and applies power to one winding that was previously idle. Given the motor geometry suggested by Figure 1.5, this control sequence will drive the motor through two revolutions.To distinguish a 5-phase motor from other motors with 5 leads, note that, if the resistance between two consecutive terminals of the 5-phase motor is R, the resistance between non-consecutive terminals will be 1.5R.Note that some 5-phase motors have 5 separate motor windings, with a total of 10 leads. These can be connected in the star configuration shown above, using 5 half-bridge driver circuits, or each winding can be driven by its own full-bridge. While the theoretical component count of half-bridge drivers is lower, the availability of integrated full-bridge chips may make the latter approach preferable.步进电机•介绍•变磁阻电机•单极电机•双极电机•单一电机•多相电机介绍步进电动机分成两类、永磁和变磁阻(也有混合电机、永磁电机与从控制器的观点)。
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步进电机的振荡、不稳定以及控制摘要:本文介绍了一种分析永磁步进电机不稳定性的新颖方法。
结果表明,该种电机有两种类型的不稳定现象:中频振荡和高频不稳定性。
非线性分叉理论是用来说明局部不稳定和中频振荡运动之间的关系。
一种新型的分析介绍了被确定为高频不稳定性的同步损耗现象。
在相间分界线和吸引子的概念被用于导出数量来评估高频不稳定性。
通过使用这个数量就可以很容易地估计高频供应的稳定性。
此外,还介绍了稳定性理论。
广义的方法给出了基于反馈理论的稳定问题的分析。
结果表明,中频稳定度和高频稳定度可以提高状态反馈。
关键词:步进电机,不稳定,非线性,状态反馈。
1. 介绍步进电机是将数字脉冲输入转换为模拟角度输出的电磁增量运动装置。
其内在的步进能力允许没有反馈的精确位置控制。
也就是说,他们可以在开环模式下跟踪任何步阶位置,因此执行位置控制是不需要任何反馈的。
步进电机提供比直流电机每单位更高的峰值扭矩;此外,它们是无电刷电机,因此需要较少的维护。
所有这些特性使得步进电机在许多位置和速度控制系统的选择中非常具有吸引力,例如如在计算机硬盘驱动器和打印机,代理表,机器人中的应用等.尽管步进电机有许多突出的特性,他们仍遭受振荡或不稳定现象。
这种现象严重地限制其开环的动态性能和需要高速运作的适用领域。
这种振荡通常在步进率低于1000脉冲/秒的时候发生,并已被确认为中频不稳定或局部不稳定[1],或者动态不稳定[2]。
此外,步进电机还有另一种不稳定现象,也就是在步进率较高时,即使负荷扭矩小于其牵出扭矩,电动机也常常不同步。
该文中将这种现象确定为高频不稳定性,因为它以比在中频振荡现象中发生的频率更高的频率出现。
高频不稳定性不像中频不稳定性那样被广泛接受,而且还没有一个方法来评估它。
中频振荡已经被广泛地认识了很长一段时间,但是,一个完整的了解还没有牢固确立。
这可以归因于支配振荡现象的非线性是相当困难处理的。
大多数研究人员在线性模型基础上分析它[1]。
尽管在许多情况下,这种处理方法是有效的或有益的,但为了更好地描述这一复杂的现象,在非线性理论基础上的处理方法也是需要的。
例如,基于线性模型只能看到电动机在某些供应频率下转向局部不稳定,并不能使被观测的振荡现象更多深入。
事实上,除非有人利用非线性理论,否则振荡不能评估。
因此,在非线性动力学上利用被发展的数学理论处理振荡或不稳定是很重要的。
值得指出的是,Taft和Gauthier[3],还有Taft和Harned[4]使用的诸如在振荡和不稳定现象的分析中的极限环和分界线之类的数学概念,并取得了关于所谓非同步现象的一些非常有启发性的见解。
尽管如此,在这项研究中仍然缺乏一个全面的数学分析。
本文一种新的数学分被开发了用于分析步进电机的振动和不稳定性。
本文的第一部分讨论了步进电机的稳定性分析。
结果表明,中频振荡可定性为一种非线性系统的分叉现象(霍普夫分叉)。
本文的贡献之一是将中频振荡与霍普夫分叉联系起来,从而霍普夫理论从理论上证明了振荡的存在性。
高频不稳定性也被详细讨论了,并介绍了一种新型的量来评估高频稳定。
这个量是很容易计算的,而且可以作为一种标准来预测高频不稳定性的发生。
在一个真实电动机上的实验结果显示了该分析工具的有效性。
本文的第二部分通过反馈讨论了步进电机的稳定性控制。
一些设计者已表明,通过调节供应频率[ 5 ],中频不稳定性可以得到改善。
特别是Pickup和Russell [ 6,7]都在频率调制的方法上提出了详细的分析。
在他们的分析中,雅可比级数用于解决常微分方程和一组数值有待解决的非线性代数方程组。
此外,他们的分析负责的是双相电动机,因此,他们的结论不能直接适用于我们需要考虑三相电动机的情况。
在这里,我们提供一个没有必要处理任何复杂数学的更简洁的稳定步进电机的分析。
在这种分析中,使用的是d-q模型的步进电机。
由于双相电动机和三相电动机具有相同的d-q模型,因此,这种分析对双相电动机和三相电动机都有效。
迄今为止,人们仅仅认识到用调制方法来抑制中频振荡。
本文结果表明,该方法不仅对改善中频稳定性有效,而且对改善高频稳定性也有效。
2. 动态模型的步进电机本文件中所考虑的步进电机由一个双相或三相绕组的跳动定子和永磁转子组成。
一个极对三相电动机的简化原理如图1所示。
步进电机通常是由被脉冲序列控制产生矩形波电压的电压源型逆变器供给的。
这种电动机用本质上和同步电动机相同的原则进行作业。
步进电机主要作业方式之一是保持提供电压的恒定以及脉冲频率在非常广泛的范围上变化。
在这样的操作条件下,振动和不稳定的问题通常会出现。
图1.三相电动机的图解模型用q–d框架参考转换建立了一个三相步进电机的数学模型。
下面给出了三相绕组电压方程v a = Ria+ L*dia/dt − M*dib/dt − M*dic/dt + dλpma/dt ,v b = Rib+ L*dib/dt − M*dia/dt − M*dic/dt + dλpmb/dt ,v c = Ric+ L*dic/dt − M*dia/dt − M*dib/dt + dλpmc/dt , (1)其中R和L分别是相绕组的电阻和感应线圈,并且M是相绕组之间的互感线圈。
λpma, λpmb and λpmc是应归于永磁体的相的磁通,且可以假定为转子位置的正弦函数如下λpma = λ1 sin(Nθ),λpmb = λ1 sin(Nθ− 2/3),λpmc = λ1 sin(Nθ - 2/3), (2) 其中N是转子齿数。
本文中强调的非线性由上述方程所代表,即磁通是转子位置的非线性函数。
使用Q ,d转换,将参考框架由固定相轴变换成随转子移动的轴(参见图2)。
矩阵从a,b,c框架转换成q,d框架变换被给出了[8](3)例如,给出了q,d参考里的电压(4)在a,b,c参考中,只有两个变量是独立的(ia + ib+ ic= 0),因此,上面提到的由三个变量转化为两个变量是允许的。
在电压方程(1)中应用上述转换,在q,d 框架中获得转换后的电压方程为v q = Riq+ L1*diq/dt + NL1idω + Nλ1ω,v d = Rid+ L1*did/dt −NL1iqω, (5)图2,a,b,c和d,q参考框架其中L1 = L + M,且ω是电动机的速度。
有证据表明,电动机的扭矩有以下公式T = 3/2Nλ1iq. (6)转子电动机的方程为J*dω/dt = 3/2*Nλ1iq−Bfω–Tl , (7)如果Bf是粘性摩擦系数,和Tl代表负荷扭矩(在本文中假定为恒定)。
为了构成完整的电动机的状态方程,我们需要另一种代表转子位置的状态变量。
为此,通常使用满足下列方程的所谓的负荷角δ[8]Dδ/dt = ω−ω, (8)其中ω是电动机的稳态转速。
方程(5),(7),和(8)构成电动机的状态空间模型,其输入变量是电压vq 和vd.如前所述,步进电机由逆变器供给,其输出电压不是正弦电波而是方波。
然而,由于相比正弦情况下非正弦电压不能很大程度地改变振荡特性和不稳定性(如将在第3部分显示的,振荡是由于电动机的非线性),为了本文的目的我们可以假设供给电压是正弦波。
根据这一假设,我们可以得到如下的v q 和vdvq= Vmcos(Nδ) ,vd= Vmsin(Nδ) , (9)其中Vm是正弦波的最大值。
上述方程,我们已经将输入电压由时间函数转变为状态函数,并且以这种方式我们可以用自控系统描绘出电动机的动态,如下所示。
这将有助于简化数学分析。
根据方程(5),(7),和(8),电动机的状态空间模型可以如下写成矩阵式Ẋ = F(X,u) = AX + Fn(X) + Bu , (10) 其中X = [iq id ω δ] T , u = [ω1 Tl] T 定义为输入,且ω1 = N ω0 是供应频率。
输入矩阵B 被定义为矩阵A 是F(.)的线性部分,如下F n (X)代表了F(.)的线性部分,如下输入端u 独立于时间,因此,方程(10)是独立的。
在F(X,u)中有三个参数,它们是供应频率ω1,电源电压幅度V m 和负荷扭矩T l 。
这些参数影响步进电机的运行情况。
在实践中,通常用这样一种方式来驱动步进电机,即用因指令脉冲而变化的供应频率ω1来控制电动机的速度,而电源电压保持不变。
因此,我们应研究参数ω1的影响。
3.分叉和中频振荡,设ω=ω0,得出方程(10)的平衡且φ是它的相角,φ = arctan(ω1L1/R) . (16) 方程(12)和(13)显示存在着多重均衡,这意味着这些平衡永远不能全局稳定。
人们可以看到,如方程(12)和(13)所示有两组平衡。
第一组由方程(12)对应电动机的实际运行情况来代表。
第二组由方程(13)总是不稳定且不涉及到实际运作情况来代表。
在下面,我们将集中精力在由方程(12)代表的平衡上。
附件2:外文原文Oscillation, Instability and Control of Stepper MotorsLIYU CAO and HOWARD M. SCHWARTZDepartment of Systems and Computer Engineering, Carleton University, 1125 Colonel By Drive,Ottawa, ON K1S 5B6, Canada(Received: 18 February 1998; accepted: 1 December 1998) Abstract. A novel approach to analyzing instability in permanent-magnet stepper motors is presented. It is shown that there are two kinds of unstable phenomena in this kind ofmotor: mid-frequency oscillation andhigh-frequency instability. Nonlinear bifurcation theory is used to illustrate the relationship between local instability and midfrequency oscillatory motion. A novel analysis is presented to analyze the loss of synchronism phenomenon, which is identified as high-frequency instability. The concepts of separatrices and attractors in phase-space are used to derive a quantity to evaluate the high-frequency instability. By using this quantity one can easily estimate the stability for high supply frequencies. Furthermore, a stabilization method is presented. A generalized approach to analyze the stabilization problem based on feedback theory is given. It is shown that the mid-frequency stabilityand the high-frequency stability can be improved by state feedback. Keywords: Stepper motors, instability, nonlinearity, state feedback.1. IntroductionStepper motors are electromagnetic incremental-motion devices which convert digital pulse inputs to analog angle outputs. Their inherent stepping ability allows for accurate position control without feedback. That is, they can track any step position in open-loop mode, consequently nofeedback is needed to implement position control. Stepper motors deliver higher peak torque per unit weight than DC motors; in addition, they are brushless machines and therefore require less maintenance. All of these properties have made stepper motors a very attractive selection in many position and speed control systems, such as in computer hard disk drivers and printers, XY-tables, robot manipulators, etc.Although stepper motors have many salient properties, they suffer from an oscillation or unstable phenomenon. This phenomenon severely restricts their open-loop dynamic performance and applicable area where high speed operation is needed. The oscillation usually occurs at stepping rates lower than 1000 pulse/s, and has been recognized as a mid-frequency instability or local instability [1], or a dynamic instability [2]. In addition, there is another kind of unstable phenomenon in stepper motors, that is, the motors usually lose synchronism at higher stepping rates, even though load torque is less than their pull-out torque. This phenomenon is identified ashigh-frequency instability in this paper, because it appears at much higher frequencies than the frequencies at which the mid-frequency oscillation occurs. The high-frequency instability has not been recognized as widely as mid-frequency instability, and there is not yet a method to evaluate it.Mid-frequency oscillation has been recognized widely for a very long time, however, a complete understanding of it has not been well established. This can be attributed to the nonlinearity that dominates the oscillation phenomenon and is quite difficult to deal with.384 L. Cao and H. M. SchwartzMost researchers have analyzed it based on a linearized model [1]. Although in many cases, this kind of treatments is valid or useful, a treatment based on nonlinear theory is needed in order to give a better description on this complex phenomenon. For example, based on a linearized model one can only see that the motors turn to be locally unstable at some supply frequencies, which does not give much insight into the observed oscillatoryphenomenon. In fact, the oscillation cannot be assessed unless one uses nonlinear theory.Therefore, it is significant to use developed mathematical theory on nonlinear dynamics to handle the oscillation or instability. It is worth noting that Taft and Gauthier [3], and Taft and Harned [4] used mathematical concepts such as limit cycles and separatrices in the analysis of oscillatory and unstable phenomena, and obtained some very instructive insights into the socalled loss of synchronous phenomenon. Nevertheless, there is still a lack of a comprehensive mathematical analysis in this kind of studies. In this paper a novel mathematical analysis is developed to analyze the oscillations and instability in stepper motors.The first part of this paper discusses the stability analysis of stepper motors. It is shown that the mid-frequency oscillation can be characterized as a bifurcation phenomenon (Hopf bifurcation) of nonlinear systems. One of contributions of this paper is to relate the midfrequency oscillation to Hopf bifurcation, thereby, the existence of the oscillation is proved theoretically by Hopf theory. High-frequency instability is also discussed in detail, and a novel quantity is introduced to evaluate high-frequency stability. This quantity is very easyto calculate, and can be used as a criteria to predict the onset of the high-frequency instability. Experimental results on a real motor show the efficiency of this analytical tool.The second part of this paper discusses stabilizing control of stepper motors through feedback. Several authors have shown that by modulating the supply frequency [5], the midfrequencyinstability can be improved. In particular, Pickup and Russell [6, 7] have presented a detailed analysis on the frequency modulation method. In their analysis, Jacobi series was used to solve a ordinary differential equation, and a set of nonlinear algebraic equations had to be solved numerically. In addition, their analysis is undertaken for a two-phase motor, andtherefore, their conclusions cannot applied directly to our situation, where a three-phase motor will be considered. Here, we give a more elegant analysis for stabilizing stepper motors, where no complex mathematical manipulation is needed. In this analysis, a d–q model of stepper motors is used. Because two-phase motors and three-phase motors have the same q–d model and therefore, the analysis is valid for both two-phase and three-phase motors. Up to date, it is only recognized that the modulation method is needed to suppress the midfrequency oscillation. In this paper, it is shown that this method is not only valid to improve mid-frequency stability, but also effective to improve high-frequency stability.2. Dynamic Model of Stepper MotorsThe stepper motor considered in this paper consists of a salient stator with two-phase or threephase windings, and a permanent-magnet rotor. A simplified schematic of a three-phase motor with one pole-pair is shown in Figure 1. The stepper motor is usually fed by a voltage-source inverter, which is controlled by a sequence of pulses and produces square-wave voltages. Thismotor operates essentially on the same principle as that of synchronous motors. One of major operating manner for stepper motors is that supplying voltage is kept constant and frequencyof pulses is changed at a very wide range. Under this operating condition, oscillation and instability problems usually arise.Figure 1. Schematic model of a three-phase stepper motor.A mathematical model for a three-phase stepper motor is established using q–d framereference transformation. The voltage equations for three-phase windings are given byv a = Ria+ L*dia/dt − M*dib/dt − M*dic/dt + dλpma/dt ,v b = Rib+ L*dib/dt − M*dia/dt − M*dic/dt + dλpmb/dt ,v c = Ric+ L*dic/dt − M*dia/dt − M*dib/dt + dλpmc/dt ,where R and L are the resistance and inductance of the phase windings, and M is the mutual inductance between the phase windings. _pm a, _pm b and _pm c are the flux-linkages of thephases due to the permanent magnet, and can be assumed to be sinusoid functions of rotor position _ as followλpma = λ1 sin(Nθ),λpmb = λ1 sin(Nθ− 2/3),λpmc = λ1 sin(Nθ - 2/3),where N is number of rotor teeth. The nonlinearity emphasized in this paper is represented by the above equations, that is, the flux-linkages are nonlinear functions of the rotor position.By using the q; d transformation, the frame of reference is changed from the fixed phase axes to the axes moving with the rotor (refer to Figure 2). Transformation matrix from the a; b; c frame to the q; d frame is given by [8]For example, voltages in the q; d reference are given byIn the a; b; c reference, only two variables are independent (ia C ib C ic D 0); therefore, the above transformation from three variables to two variables is allowable. Applying the abovetransformation to the voltage equations (1), the transferred voltage equation in the q; d frame can be obtained asv q = Riq+ L1*diq/dt + NL1idω + Nλ1ω,v d =Rid+ L1*did/dt − NL1iqω, (5)Figure 2. a, b, c and d, q reference frame.where L1 D L C M, and ! is the speed of the rotor.It can be shown that the motor’s torque has the following form [2]T = 3/2Nλ1i qThe equation of motion of the rotor is written asJ*dω/dt = 3/2*Nλ1iq− Bfω– Tl ,where Bf is the coefficient of viscous friction, and Tl represents load torque, which is assumed to be a constant in this paper.In order to constitute the complete state equation of the motor, we need another state variable that represents the position of the rotor. For this purpose the so called load angle _ [8] is usually used, which satisfies the following equationDδ/dt = ω−ω,where !0 is steady-state speed of the motor. Equations (5), (7), and (8) constitute the statespace model of the motor, for which the input variables are the voltages vq and vd. As mentioned before, stepper motors are fed by an inverter, whose output voltages are not sinusoidal but instead are square waves. However, because the non-sinusoidal voltages do not change the oscillation feature and instability very much if compared to the sinusoidal case (as will be shown in Section 3, the oscillation is due to thenonlinearity of the motor), for the purposes of this paper we can assume the supply voltages are sinusoidal. Under this assumption, we can get vq and vd as followsv q = Vmcos(Nδ) ,v d = Vmsin(Nδ) ,where Vm is the maximum of the sine wave. With the above equation, we have changed the input voltages from a function of time to a function of state, and in this way we can represent the dynamics of the motor by a autonomous system, as shown below. This will simplify the mathematical analysis.From Equations (5), (7), and (8), the state-space model of the motor can be written in a matrix form as followsẊ = F(X,u) = AX + Fn(X) + Bu , (10) where X D T iq id ! _U T , u D T!1 Tl U T is defined as the input, and !1 D N!0 is the supply frequency. The input matrix B is defined byThe matrix A is the linear part of F._/, and is given byFn.X/ represents the nonlinear part of F._/, and is given byThe input term u is independent of time, and therefore Equation (10) is autonomous.There are three parameters in F.X;u/, they are the supply frequency !1, the supply voltage magnitude Vm and the load torque Tl . These parametersgovern the behaviour of the stepper motor. In practice, stepper motors are usually driven in such a way that the supply frequency !1 is changed by the command pulse to control the motor’s speed, while the suppl y voltage is kept constant. Therefore, we shall investigate the effect of parameter !1.3. Bifurcation and Mid-Frequency OscillationBy setting ! D !0, the equilibria of Equation (10) are given asand ' is its phase angle defined byφ = arctan(ω1L1/R) . (16) Equations (12) and (13) indicate that multiple equilibria exist, which means that these equilibria can never be globally stable. One can see that there are two groups of equilibria as shown in Equations (12) and (13). The first group represented by Equation (12) corresponds to the real operating conditions of the motor. The second group represented by Equation (13) is always unstable and does not relate to the real operating conditions. In the following, we will concentrate on the equilibria represented by Equation (12).。