PLC建筑电梯控制系统中英文对照外文翻译文献
基于PLC的电梯控制系统设计中英文翻译
Elevator System Based on PLCComposed by the order of relay control system is a realization of the first elevator control method. However, to enter the nineties, with the development of science and technology and the widespread application of computer technology, the safety of elevators, reliability of the increasingly high demand on the relay control weaknesses are becoming evident.Elevator control system relays the failure rate high, greatly reduces the reliability and safety of elevators, and escalators stopped often to take with the staff about the inconvenience and fear. And the event rather than taking the lift or squat at the end of the lift will not only cause damage to mechanical components, but also personal accident may occur.Programmable Logic Controller (PLC) is the first order logic control in accordance with the needs of developed specifically for industrial environment applications to operate the electronic digital computing device. Given its advantages, at present, the relay control the lift has been gradually replaced by PLC control. At the same time, AC variable frequency motor speed control technology, the way the lift drag speed has been a gradual transition form DC to AC frequency converter. Thus, PLC control technology increases VVVF Elevator modern technology has become a hot industry.1. PLC elevator control advantages:(1) Used in elevator control PLC, with so ware for automatic control of lift operation, reliability greatly increased.(2) Layer was removed and majority of the relay, the control system structure is simple, simplify the external circuit.(3) PLC can be a variety of complex control system, easy to add or change control functions.(4) PLC can be automated fault detection and alarm display to improve the operation of security and ease of maintenance.(5) For the group control the allocation and management, and improve the efficiency of elevator operation.(6)Do not need to change the control scheme changes when the hardware connection.2. VVVF elevator control characteristics.With the power electronics, microelectronics and computer technology to control the rapid development of technology, communication technology VVVF also a very rapid rate. AC variable frequency motor speed control technology is the power to improve the process in order to improve product quality and improving the environment and promoting technological progress as a primary means. Frequency of its excellent performance and the speed brake from a smooth performance, high efficiency, high power factor and power-saving of a broad scope of application and many other advantages of being at home and abroad recognized as the most promising approach speed.Exchange characteristics of VVVF Elevator:(1) low energy consumption.(2) low load circuit, the re emergency power supply device of small.In the acceleration stage, the required start-up current of less than 2.5 times the rated current. Peak starting current and time is short. Since the starting current is drastically reduced, so power consumption and power supply cable diameter can be reduced a lot. Required for emergency power supply devices are also relatively small size.(3) high reliability and long service life.(4) good comfort.Elevator operation is best to follow the speed curve of a given operation. Their characteristics can be adapted to human feelings, and to ensure that noise operation, smooth brake Ping layer and high precision.(5) stable noise-free.(6) In the car, the engine room and adjacent areas to ensure that noise. Because their systems use a high clock frequency. Always produce a true sine wave power supply current yet. Motor torque ripple does not appear. Therefore, to eliminate vibration and noise.3. Elevator control technology.The so-called elevator control technology refers to the elevator drive system and electrical control system of automatic control. 70 as the 20th century in China’s elevator were marked by the exchange of two-speed elevator. Its speed is used to change the elevator traction motor of the very few, two or mute-level approach to the number of windings, very few of them as high-speed winding of the winding, a very few number of windings as the low-speed winding. Windings for high-speed elevator-speed start-up and running, low-speed windings for braking and the maintenance of elevators.The early 80s, VVVF inverter controlled variable lift system available. It uses AC motor drivers, are able to reach the level of DC motor, control the speed of the current has reached 6 m/sec. Its small size, light weight, high efficiency, energy saving, inc1uding the past almost all the advantages of the lift. Is the latest elevator drive systemOperation in vertical lift, there is also the starting point of the terminus station. For more than three-story elevator buildings, the starting point of the terminal stations and stops between the had not, the starting point for these stations at the first floor of the terminal located at the highest floor. Starting point in the first floor of the station known as base stations, known as the starting point at both ends of the terminal stations and stations at both ends of intermediate stops between stations.Outside the station has a call box, box set are used by staff for elevator call button or touch the call button, the general ends of the lift stations in the call box on the Settings button or touch of a button. 1iddle layer of the station set up the call box button or touch button 2. No drivers for the control of elevators, at various stations are set up calls me on a button or touch button. Elevator car and the internal settings (except for debris elevator) to manipulate me. Control box switch on the handle or set up stations and the corresponding layer of buttons or touch-button control box on the touch-control button or command button or touch the city button. Outside the command button or touch-button issue as the signal outside the command signal, within the commandbutton or touch-button issue within the signal as a command signal. 80 In the mid-20th century, the touch button has been replaced by micro-button.As the elevator call box outside the base station, in addition to set up a call button or touch button, but a1so set a key switch in order to work the elevator clearance. Drivers or management staff to open the elevator to the base station can wriggle through a dedicated key to the key switch. Close the elevator in place to autocratically cut off the elevator control power supply or power supply.4. PLC Control Elevator Design.With the continuous development of urban construction, the increasing high-rise buildings, elevators and life in the national economy has a broad application. Elevator high-rise buildings as a means of transport in the vertical run of daily life have been inextricably linked with people. In fact the lift is based on external call control signals, as well as the laws of their own, such as running, and the cal1 is random, the lift is actually a man-machine interactive control system, simple to use control or logic control order can not meet the control requirement, and therefore, elevator control system uses a random control logic. Elevator control is current1y generally used in two ways, first, the use of computer as a signal control unit, the completion of the lift signal acquisition, operation and function of the se, to achieve the lift and set the autocratic scheduling function to run the election, drag the control from inverter to complete; the second control mode with programmable logic controller (PLC) to replace the computer control signal sets the election. From the control and performance, these two types of methods and there is no significant difference. Most of the domestic manufacturers to choose the second approach, because the smaller scale of production there design and manufacture of high cost of computer control devices; and PLC high reliabi1ity, convenient and flexible program design, anti-interference ability, stable and reliable operation of the characteristics of Therefore, the elevator control system is now widely used to realize programmable control.5. Lift control system.Lift control system is used to manipulate each control process by managing such commands as running direction, car call, landing call, load signal, landing indication, safety protection.Lifts in different applications have different load, speed and drive / control modes. Lifts in same application may also have different control mode. Whatever control mode is adopted, the objective is the same, to be specific, according to car call and landing call, lift control system will execute automatic logic judgment to determine which lift will receive signal, which direction lift will run towards and complete programmed control objective through electrical automatic system based on command.Types of lift control system.Control system development chronicle indicates that there has appeared many control modes, such as such as relay control, PLC, single computer control, multiple-computer control. Prevailing in different era, these control modes are still employed in lifts now due to massive integrated circuit and computer technology development.PLC control system.As abbreviation of programmable logic controller, PLC is an electronic system featuring digital computation. It adopts programmable EPROM to execute logic computation, order control, timing, number counting, arithmetic computation, besides, it can input and output through digital or analogy modes.The mechanism of PLC control is as follows: input of PLC includes such command signals, as power key to home landing, car call, landing call, various safety switches, position signal, while output of PLC includes contactor, relay, indicators of car / landings and communication unitary, indicators inside car and switch, position signal, are input to PC, while other executing com.Programming principle is determined by lift control mode. Programming can either be made according to relay logic control circuit or individually in different phases according to lift control functions after completely separating from relay control circuit. Based on the ready made control circuit, the formeris simple and easy to master, while the latter involves less programs by integrating programs of small function.Used in lift control system, PLC has such advantages, as high reliability, stability, easy programming, user-friendliness, convenient maintenance & inspection.Nowadays, there is a wide range and series of programmable logic controllers. Input / output points range from 30 to 8000 or above, so as to meet lift control requirements with different landing number.PLC 控制下的电梯系统由继电器组成的顺序控制系统是最早的一种实现电梯控制的方法。
PLC-外文文献+翻译
Programmable logic controllerA programmable logic controller (PLC） or programmable controller is a digital computer used for automation of electromechanical processes, such as control of machinery on factory assembly lines，amusement rides，or lighting fixtures。
PLCs are used in many industries and machines. Unlike general—purpose computers，the PLC is designed for multiple inputs and output arrangements, extended temperature ranges，immunity to electrical noise，and resistance to vibration and impact. Programs to control machine operation are typically stored in battery-backed or non-volatile memory。
A PLC is an example of a real time system since output results must be produced in response to input conditions within a bounded time, otherwise unintended operation will result.1.HistoryThe PLC was invented in response to the needs of the American automotive manufacturing industry。
基于plc电梯控制外文文献翻译、中英文翻译、外文翻译
In the article has analyzed the elevator loadcharacteristics, elaborated uses the trapezoid acceleration curve theelevator ideal velocity curve, unifies the frequency changer and thePLC performance, elaborated the elevator control system constitutionand the operational factor. Elaborated the elevator speed curveproduces the method, has induced the characteristic which designs byPLC constitution control system software.Key word: Load characteristics ideal velocity curve control systemsoftware design1. OutlineAlong with the urban construction unceasing development, thehigh-rise construction unceasingly increases, the elevator has thewidespread application in the national economy and the life. Theelevator took in the high-rise construction the vertical movementtransportation vehicle already and people's daily life is inseparable.In fact the elevator is according to exterior movement and so oncalling signal as well as own control rule, but calls is stochastic,the elevator is a person machine interactive control system in fact,purely is cannot satisfy the control request with the sequentialcontrol or the logical control, Therefore, the elevator control system uses the stochastic logical waycontrol. At present the elevator control generally has selected twomethods, one is uses the microcomputer to take the signal controlunit, completes the elevator signal gathering, the running status andthe function hypothesis, realizes the elevator automatic dispatch andthe collection chooses the movement function, drives the control tocomplete by the frequency changer; The second control mode (PLC)substitutes for the microcomputer realization signal collection withthe programmable controller to choose the control. Said from the control mode and the performance, these two methodscertainly not too big difference. The domestic factory mostly choosesthe second way, its reason lies in the production scale slightly, owndesign and the manufacture microcomputer control device cost ishigher; But PLC reliability high, programming convenience nimble, theantijamming ability strong, the movement stable is reliable and so onthe characteristic, therefore the present elevator control systemwidely uses the programmable controller to realize.2. Elevator ideal performance diagramIndicated according to the massive research and the experiment, theperson may accept the maximum acceleration is am <= 1.5m/s2,acceleration rate of change rho m <= the 3m/s3, elevator idealperformance diagram may divide according to the acceleration is thetriangle, the trapezoid and the sine profile, As a result of sine profile acceleration curve realization moredifficult, but the triangle curve maximum acceleration and is startingand applies the brake the section turning point acceleration rate ofchange to be bigger than the trapezoidal curve, namely + rho m jumpsto - rho m or jumps from - rho m to + rho the m acceleration rate ofchange, therefore very little uses, because the trapezoidal curve iseasy to realize and has the good acceleration rate of change frequenttarget, therefore is widely used, uses the trapezoidal accelerationcurve elevator ideal performance diagram like chart 1 to show: The intelligent frequency changer is for the elevator special-purposefrequency changer request and so on elevator nimble velocitymodulation, control and high accuracy even level which but speciallydesigns, may use for parts the general three-phase asynchronous motor,and has function and so on intellectualized software, standardconnection, menu prompt, input elevator curve and other essentialparameter. It has the debugging convenience quickly, moreover can automaticallyrealize the single multilayered function, and has the automaticoptimization deceleration curve the function, is composed the velocitymodulation system crawling time by it few, the even level distance isshort, no matter is the double winding electric motor, or electric motor suitable, its highest design speed may reach 4m/s, itsunique computer monitoring software, may choose the serial interfacerealization input/output signal the non- electronic contact control. The frequency changer constitutes elevator system, when the frequencychanger receives the controller to send out shouts the ladderdirection signal, the frequency changer basis hypothesis speed and theacceleration value, the starting motor, after achieved the maximumspeed, the uniform speed moves, when arrives the goal leveldecelerates, the controller sends out shuts off the high velocitysignal, reduces the speed which the frequency changer establishes themaximum speed to reduce to the crawling speed, In decelerates in the movement process, the frequency changer can theautomatic computation decelerate to the even level spot betweendistance, and calculates the optimized curve, thus canaccording tothe optimized curve movement, cause the low speed crawling time toreduce to 0.3s, the frequency changer through adjusts leveling thespeed in the elevator even level process or applies the brake thepitch to adjust leveling the precision. Namely when the elevator stops too early, the frequency changerincreases the low speed value or the reduction applies the brake thepitch value, otherwise reduces the low speed value or increasesapplies the brake the pitch value, when the elevator to leaves evenlevel position 4 - 10cm, has the even level switch automaticseparation low speed signal, the system according to the optimizedcurve realization high accuracy even level, thus achieved the evenlevel accurate is reliable.3. Elevator speed curveElevator movement comfortableness is decided in its movementprocess acceleration a and the acceleration rate of change p size, theoversized acceleration or the acceleration rate of change can createpassenger's ill feeling. At the same time, for guaranteed the elevatorthe operating efficiency, a, the p value not suitable excessively issmall. Can guarantee a, the p best value elevator performance diagramis called the elevator the ideal performance diagram. The elevatormovement ideal curve should be the parabola - straight linecomprehensive velocity curve, namely elevator Canada, reduces theprocess constitutes by the parabola and the straight line. Theelevator assigns the curve is whether ideal, direct influence actualperformance diagram.3.1 velocity curves have the methodUses FX2-64MR PLC, and a consideration input output requestincreased FX-8EYT, FX-16EYR, the FX-8EYR three expansions modules andthe FX2-40AW twisted pair line correspondence adapter, FX2-40AW usesin the system serial communication. Using PLC the expansion functionmodule D/A module realization speed ideal curve output, whenbeforehand the digitized ideal velocity curve stores the PLC register,the procedure movement, through looks up the table way to read in D/A,transforms the simulation quantity after D/A the speed ideal curveoutput.3.2 Acceleration assign the curve the production8 D/A outputs 0 ~ 5V/0 ~ 10V, the corresponding numerical valueis 16 enters system several 00 ~ FF, altogether 255 levels. Ifelevator rise time between 2.5 ~ 3seconds. According to theconservative value computation, in the elevator acceleration processeach time Zha Biao time-gap not suitably surpasses 10ms.As a result of elevator logic control section procedure biggest, butthe PLC movement uses the cyclical scanning mechanism, thus usuallyuses looks up the table method, Zha Biao instruction time-gapexcessively is each time long, cannot satisfiedly assign the curve theprecision request. In the PLC movement process, its CPU with variousequipment between exchange of information, user program execution,signal gathering, control quantity operation and so on output all isdefers to the fixed order to circulate the scanning way to carry on,each circulation all must carry on the inquiry, the judgement and theoperation to all functions. This kind of order and the form capableperson are not the change. The usual scanning cycle, is basic mustcomplete six steps the work, including movement surveillance, andprogramming exchange information, and digital processor exchangeinformation, and communication processor exchange information,execution user program and input output connection service and so on.In a cycle, CPU only carries out to the entire user program. This kindof mechanism has its convenient one side, but timeliness is bad. Theexcessively long scanning time, directly affects the system to thesignal response effect, in under the guarantee control functionpremise, maximum limit reduces CPU the cyclical scanning time is avery complex question. Generally only can short adopt the method fromthe user program execution time. The elevator logic control sectionprocedure scanning time has surpassed 10ms, although has adopted somereduced procedure scanning time means, but still will be unable toscan the time to fall to 10ms below. At the same time, applies thebrake the section curve to use according to is away from theprinciple, each section of distances arrive the response time notsuitably surpasses 10ms. In order to satisfy the system the timelyrequest, in the velocity curve production way, uses the severancemethod, thus effectively has overcome the PLC scanning mechanismlimit.The starting acceleration movement by decides the cycle interruptservice isr to complete. This kind of severance cannot carry on theswitch by the procedure, once establishes, continuously presses thehypothesis time-gap circulation severance,therefore, the startingmovement condition must put in the interrupt service isr, when doesnot satisfy the movement condition, the severance namely returns.3.2 Decelerates applies the brake the curve productionIn order to guarantee applies the brake process completing,must carry on in the master routine applies the brake the condition tojudge and to decelerate a determination. In decelerates before adetermination, the elevator continuously is in the acceleration or thesteady fast movement process. The acceleration process completes bythe fixed cyclical severance, accelerates after the correspondingpattern maximum value, the acceleration procedure movement conditionno longer satisfies, after each time severs, no longer carries out theacceleration procedure, directly returns from the severance. Theelevator corresponds the pattern the maximum value movement,decelerates in this pattern to after, has the high-speed countingseverance, the execution decelerates the service routine. Revises thecounter in this interrupt service isr to suppose the definite valuethe condition, guaranteed the next time will sever the execution. In the PLC internal register, deceleration curve table value from big to small , each time severs all carries out time "theindicator needle to add 1" the operation, then the next severance willlook up the table number is smaller than this severance to look up the table numbers. Thegate area peaceful level area judgement produces by exterior signal,guarantees the moderating process the reliability.4. Elevator control system4.1 Elevators control system characteristicIs relates the elevator movement comfortable feeling target in theelevator performance diagram start section the key link, but thecomfortable feeling with the acceleration direct correlation,according to controls the theory, must cause some quantity accordingto prearrange the rule change to have to carry on the positivegoverning to it, said regarding the elevator control system, mustcause the acceleration to have to use the acceleration feedbackaccording to the ideal curve change, according to electric motormoment of force equation: M - MZ= Delta M=J (dn/dt), obviously theacceleration rate of change had reflected the system dynamic extensionis apart from the change, the control acceleration is apart from DeltaM=M - MZ on the control system dynamic extension. Therefore uses theacceleration in thissection the timing control principle, when thestart ascent portion speed achieved when stable state value 90%,systematically will cut the speed control from the accelerationcontrol, because in the steady fast section, the speed will besmaller for the permanent value control undulation, the accelerationchange will not be big, also will use the speed closed-loop controlto be allowed to cause the stable state speed hold certain precision,will be applies the brake the section precise even level to create thecondition. Uses the PI regulator control in the system speed ascentportion and steady fast Duan Suidu, but two section of PI parameter isdifferent, enhances the system the dynamic response target.Applies the brake the section in the system, namely must to reduce thespeed to carry on the essential control, guarantees the comfortablefeeling, also must strictly controls according to the elevatormovement speed and the distance relations, guarantees the even levelthe precision. In system’s rotational speed reduces to 120r/min in front of, in orderto enable two to obtain the proper attention to both, adopts by theacceleration to the timing control primarily, simultaneously actsaccording to on each as soon as the stopping distance the actualrotational speed and the theory rotational speed deviation revises theacceleration to assign the curve the method. For example in is awayfrom the even level spot some as soon as to be away from L place, thespeed should reduce to Vm/s, but the actual rotational speed is highis V ' m/s, then explained adds the system turns is apart frominsufficiently, after therefore calculates the here to assign reducesspeed value -ag, causes it to add on a negative deviation againepsilon, even if the here reduces the speed given value to revise for- (ag+ epsilon) causes to assign reduces the speed and the true speednegative deviation enlarges, thus enlarged the system to turn thedistance, caused the speed very quickly to fall to the standard value,when electric motor’s rotational speed reduces to 120r/min after, this time thetheater box above the level only had several centimeters, The elevatorrunning rate is very low, for did not prevent phenomenon appearancewhich stops to the even level area, enables the elevator comparativelyquickly to enter the even level area, uses the proportional control inthis section, and uses the time optimization control, guaranteed theelevator accurately promptly enters the even level area, achieves theaccurate reliable even level.4.2 elevators controls constitutionBecause the elevator movement is according to the floor and the theater box calling signal, the travelling schedule signalcarries on the control, but the floor and the theater box call isstochastic, therefore, the systems control uses the stochastic logicalcontrol. Namely in realizes in the elevator basic control requestfoundation by the smooth logic control, according to stochastic inputsignal, as well as elevator corresponding condition at the rightmoment control elevator movement. Moreover, the theater boxposition is determined by the pulse encoder pulse number that, anddelivers PLC the counter to carry on the control. At the same time,each building establishes to approach the switch to use in to examinethe system the floor signal. In order to be advantageous for the observation, is at the floor tothe elevator movement direction as well as the elevator to carry onthe demonstration, uses LED and the photo tube demonstrated, but tothe floor and the theater box calling signal to the indicating lampdemonstrated (on switch has indicating lamp).In order to enhance the elevator the operating efficiency peacefullevel precision, the system requests PLC to be able to theater boxCanada, to decelerate as well as to apply the brake to carry on theeffective control. Realizes according to the theater box physicallocation as well as the exchange velocity modulation system controlalgorithm. For the elevator movement security, the system shouldestablish the reliable fail safe and the corresponding es the PLC realization the elevator control system to constitute byfollowing several main parts.4.2.1 PLC control circuit; PLC receives shouts the ladder from thepanel board and each level to summon the signal, the theater boxand the gate system function signal as well as the well and thefrequency changer condition signal, realizes the elevator collectionafter the procedure judgement and the operation to choose the control.PLC during the output demonstration and supervisory signal, sends outthe movement direction, the start, Canada to the frequencychanger/decelerates moves and applies the brake to stop the ladderequisignal.4.2.2 electric currents, speed double closed loops electric circuit;Frequency changer itself is equipped with the electric currentdetector set, from this constitution electric current closed loop;Through revolves the encoder with the electricalmachinery coaxialjoint, produces a, the b two pulses enters the frequency changer,during confirmation direction, counts the constitution speed closedloop using the pulse.4.2.3 displacements control circuit; The elevator took one kindcarries the person tool, reigns under the potential state of loading,besides request safe reliable, but also requests the movement to besteady, rides comfortably, anchors accurately. Uses the frequencyconversion to modulate velocity Shuanghuan to control may basicallyanswer the purpose, the use existing revolves the encoder toconstitute the speed ring at the same time, moves the proportionthrough the frequency changer PG card output and the electricalmachinery speed and the elevator the pulse number, introduces it PLChigh-speed counting to input the port, through the accumulation pulsenumber, (1) calculates the pulse equivalent after the type, from thisdefinite elevator position. Elevator displacement H=SI In the formula I - accumulation pulse number; S - pulse equivalent; S = plD/(pr) (1) L – Proportion of decelerates ; D - tows the wheel diameter; P - revolves the encoder every time to transfer corresponding thepulse number; R - PG card frequency division ratio.4.2.4 ends stations protection; When in elevator direction detectionline, on the good directional relay, the express train assistancecontact device, the express train movement contact device, the doorlock relay, on the good contact device electricity attracts gathers, mechanical floodgate opens, on elevator line. When the theater box bumps intoforces speed changeing the switch, the PLC internal lock saves the relay toresult in the electricity to attract gathers, timer Tim10, Tim11 startfixed time, it fixed time time length visible end station leveldistance with ladder fast hypothesis. After on forces speed changing theswitch movement, the elevator transfers the slow train movement by theexpress train movement, in the normal condition, the previous line ofeven strata time elevator should stop. If the theater box has notstopped continues the line, when Tim10 supposes the definite value toreduce the zero hour, it the separation, the slow traincontact device and on the good contact device loses the electricity,the elevator stops moving. Bumps into after the arrogant theater boxon forces speed changing the switch, because certain reason elevators have notbeen able to transfer the slow train movement, and the express trainmovement contactdevice has not been able to release, when Tim11supposes the definite value to reduce the zero hour, it N.C. contactthe separation, the express train movement contact device and on thegood contact device loses the electricity, the elevator stops moving.Therefore, no matter is the slow train movement or the express trainmovement, so long as on forces speed changing the switch to send out thesignal, no matter the end stands other protection switches whetheract, can cause the elevator with the aid of Tim10 and Tim11 to stopmoving, thus causes the elevator end station protection to be morereliable.Under when the elevator needs the line, so long as had has chosen theladder instruction, got down the good directional relay to result inelectricity its Chang Kaidian closed, the lock saved the relay toreposition, Tim10 and Tim11 lost the electricity, it N.C. contactclosed for the elevator normal under line has prepared for. The lowerextremity stands the protection principle and the upper extremestation protection similar no longer duplicates.4.2.5 floors count; The floor counts uses relatively counts the way.Before the movement through from the study way, determines thecorresponding floor highly pulse number, corresponds 17 elevatorsseparately to store 16 memories units DM06 ~ DM21. The floor counter(CNT46) is a bidirectional counter, when arrives each level the floorcounts, according to moves the direction to carry on adds 1 or reduces1 to count. In the movement, the high speed counter tiredly estimates the valuereal-time counts the point correspondence pulse number with the floorto carry on the comparison, is equal when sends out the floor to countthe signal, the previous line of Canada 1, the next line reduces 1. Inorder to prevent the counter in counts the pulse high level periodrepetition to count, uses the floor to count on the signal along totrigger the floor counter.4.2.6 is fast speed changing; When the high speed counter value and the fastspeed changing point correspondence pulse number is equal, if the elevator isin the quick operating also this level has chooses the level signal,sends the fast speed changing signal. If the elevator medium speed movement oralthough the quick operating but this not chooses the level signal,then does not send speed changing the signal.4.2.7 areas signals; When high speed counter CNT47 value correspondsin the pulse number scope when the gate area, sends the gate areasignal.4.2.8 pulses signals failure detection; Pulse signal accurategathering and the transmission appears in the system especiallyimportantly, revolves the encoder for the examination and the pulsetransmission circuit breakdown, whether there is has designed thepulse signal and the errors and omissions pulse examination electriccircuit, guarantees the system normal operation through the real-timeexamination. In order to eliminate the pulse to count the accumulativeerror, in base station the establishment reset switch, turns on PLC highspeed counter CNT47 the replacement end.5. Software design characteristic5.1 uses the priority formationPosition and movement direction locates which according to theelevator, in the programming, has used four priorities formations,namely on good priority formation, on line of inferior priorityformation, under good priority formation, next line of inferiorpriority formation. When among them, on good priority formation forelevator upward movement, locates the upward movement calling signalin the elevator which above the position the floor sends out, thearray which should call which the signal cabin correspondence thefloor to have the pulse number depositing register constitutes. Whenprevious line of inferior priority formation for elevator upwardmovement, locates the upward movement calling signal in the elevatorwhich below the position the floor sends out, the formation whichshould call which the signal cabin correspondence the floor to havethe pulse number depositing register constitutes. Control system inelevator movement real-time arrangement four priorities exhibition,has provided the foundation for the realization stochastic logiccontrol.5.2 uses advanced first leaves the formationAccording to elevator movement direction, with to the priorityformation's in non-vanishing unit (has when call this unit is 70units, does not have when call then this unit for zero) (advancedsends in the register formation first to leave formation FIFO), theuse advanced first leaves the read-out instruction SFRDP instruction,sends in the FIFO first unit in data compares the register.5.3 uses the stochastic logical controlWhen the elevator approaches by some movement direction somefloor decelerates the position, distinguished whether this floor doeshave with to the calling signal (on a line of call symbolizedregister, next line of call symbolized when register, has callrequest, corresponding register is l, otherwise is 0), if has, thecorresponding register pulse number and the comparison register willcarry on the comparison, if will be same, then will decelerate in thisfloor stops: If is not same, then sends in this register data comparesthe register, and the original comparison register data preservation,carries out this floor to decelerate stops. After this movementfinished, the data which will preserve reis sent in compares theregister, will realize the stochastic logical control.5.4 uses the software demonstration The system use travelling schedule judgement floor, andtransforms the BCD code output, through hardware connection electriccircuit by LED demonstration.5.5 pair of frequency changers control PLC acts according to the stochastic logical control therequest, may send out to the frequency changer to the movement, thereverse movement, is decelerating as well as applies the brake thesignal, again controls the electrical machinery by the frequencychanger basis certain control rule and the control algorithm. At thesame time, when the system appears the breakdown, PLC to the frequencychanger sends out the signal.6. Concluding remark Uses elevator control system which the MIC340 elevatorspecial-purpose frequency changer constitutes, may realize theintellectualization which the elevator controls, but because theperiod of five days ladder and the elevator in person arrives eachlevel the population is the intelligent elevator is unable todetermine, even if uses the AITP artificial intelligence system, thetransmission transportation passenger flow information also is fuzzy,for solves the elevator this vertical transportation control systemtwo to be big cannot know the factor, will need us to go to theunceasing research and the exploration in the next work.译文:文中分析了电梯的负载特性，阐述了采用梯形加速曲线的电梯理想速度曲线，结合变频器和PLC的性能，论述了电梯控制系统的构成和工作特性。
PLC控制系统外文翻译
附录Abstract: Programmable controller in the field of industrial control applications, and PLC in the application process, to ensure normal operation should be noted that a series of questions, and give some reasonable suggestions.Key words: PLC Industrial Control Interference Wiring Ground Proposal DescriptionOver the years, programmable logic controller (hereinafter referred to as PLC) from its production to the present, to achieve a connection to the storage logical leap of logic; its function from weak to strong, to achieve a logic control to digital control of progress; its applications from small to large, simple controls to achieve a single device to qualified motion control, process control and distributed control across the various tasks. PLC today in dealing with analog, digital computing, human-machine interface and the network have been a substantial increase in the capacity to become the mainstream of the field of control of industrial control equipment, in all walks of life playing an increasingly important role.ⅡPLC application areasCurrently, PLC has been widely used in domestic and foreign steel, petroleum, chemical, power, building materials, machinery manufacturing, automobile, textile, transportation, environmental and cultural entertainment and other industries, the use of mainly divided into the following categories:1. Binary logic controlReplace traditional relay circuit, logic control, sequential control, can be used to control a single device can also be used for multi-cluster control and automation lines. Such as injection molding machine, printing machine, stapler machine, lathe, grinding machines, packaging lines, plating lines and so on.2. Industrial Process ControlIn the industrial production process, there are some, such as temperature, pressure, flow, level and speed, the amount of continuous change (ie, analog), PLC using the appropriate A / D and D / A converter module, and a variety of control algorithm program to handle analog, complete closed-loop control. PID closed loop control system adjustment is generally used as a conditioning method was more. Process control in metallurgy, chemical industry, heat treatment, boiler control and so forth have a very wide range of applications3. Motion ControlPLC can be used in a circular motion or linear motion control. Generally use a dedicated motion control module, for example a stepper motor or servo motor driven single-axis or multi-axis position control module, used in a variety of machinery, machine tools, robots, elevators and other occasions.4. Data ProcessingPLC with mathematics (including matrix operations, functions, operation, logic operation), data transfer, data conversion, sorting, look-up table, bit manipulation functions, you can complete the data collection, analysis and processing. Dataprocessing is generally used, such as paper making, metallurgy, food industry, some of the major control system5. Communications and networkingPLC communication with the communication between PLC and the PLC and other communications between intelligent devices. Along with the development of factory automation network, the PLC now has communication interface, communication is very convenient.ⅢApplication features of PLC1. 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 failure 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 welcomePLC 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 changed production process possible. This is particularly suitable for many varieties, small batch production situations.(1)Installation and wiring●Power lines, control lines and power lines and PLC I / O lines should be split wiring, isolation transformer and PLC and I / O should be used between the cable connection Shuangjiao. The PLC's IO lines and power lines go separate lines, such as to be in the same groove, the separation of bundled communication lines, DC lines, if conditions allow, the best sub-groove alignment, not only will it have the greatest possible distance and can reduce the noise to a minimum.●PLC should stay away from strong interference sources such as welding, high-power silicon rectifier devices and large power equipment, not with the high-voltage electrical switch installed in the same cabinet. PLC in the cabinet should stay away from power lines (the distance between the two should be more than 200mm). And PLC cabinets installed within the same inductive load, such as large power relay, contactor coil, arc should be parallel RC circuit.●PLC input and output separately from the best alignment, switch and analog should be laid separately. The transmission of analog signals should be shielded cable, one end or both ends of the shield should be grounding resistance should be less than the shielding layer 1 / 10.●AC output line and DC output lines do not use the same cable, the output line should be far from power lines and power lines, to avoid parallel.(2)I / O wiring terminalInput Connection●Input wiring generally not too long. But if the environment interfere with small, small voltage drop, the input terminal can be properly longer.●Input / output lines can not be used with a cable, input / output lines should be separated.●The extent possible, normally open contact form to connect to the input in the establishment of the ladder and relay the same schematic, easy to read。
(完整版)PLC英文文献+翻译
自动化专业本科毕业设计英文翻译学院(部)：专业班级：学生姓名：指导教师：年月日Programmable Logic ControllerONE：PLC overviewProgrammable controller is the first in the late 1960s in the United States, then called PLC programmable logic controller (Programmable Logic Controller) is used to replace relays. For the implementation of the logical judgment, timing, sequence number, and other control functions. The concept is presented PLC General Motors Corporation. PLC and the basic design is the computer functional improvements, flexible, generic and other advantages and relay control system simple and easy to operate, such as the advantages of cheap prices combined controller hardware is standard and overall. According to the practical application of target software in order to control the content of the user procedures memory controller, the controller and connecting the accused convenient target.In the mid-1970s, the PLC has been widely used as a central processing unit microprocessor, import export module and the external circuits are used, large-scale integrated circuits even when the Plc is no longer the only logical (IC) judgment functions also have data processing, PID conditioning and data communications functions. International Electro technical Commission (IEC) standards promulgated programmable controller for programmable controller draft made the following definition : programmable controller is a digital electronic computers operating system, specifically for applications in the industrial design environment. It used programmable memory, used to implement logic in their internal storage operations, sequence control, timing, counting and arithmetic operations, such as operating instructions, and through digital and analog input and output, the control of various types of machinery or production processes. Programmable controller and related peripherals, and industrial control systems easily linked to form a whole, to expand its functional design. Programmable controller for the user, is a non-contact equipment, the procedures can be changed to change production processes. The programmable controller has become a powerful tool for factory automation, widely popular replication.Programmable controller is user-oriented industries dedicated control computer, with many distinctive features.First, high reliability, anti-interference capability;Second，programming visual, simple;Third, adaptability good;Fourth functional improvements, strong functional interface. TWO：History of PLCProgrammable Logic Controllers (PLC), a computing device invented by Richard E. Morley in 1968, have been widely used in industry including manufacturing systems, transportation systems, chemical process facilities, and many others. At that time, the PLC replaced the hardwired logic with soft-wired logic or so-called relay ladder logic (RLL), a programming language visually resembling the hardwired logic, and reduced thereby the configuration time from 6 months down to 6 days [Moody and Morley, 1999].Although PC based control has started to come into place, PLC based control will remain the technique to which the majority of industrial applications will adhere due to its higher performance, lower price, and superior reliability in harsh environments. Moreover, according to a study on the PLC market of Frost and Sullivan [1995], an increase of the annual sales volume to 15 million PLC per year with the hardware value of more than 8 billion US dollars has been predicted, though the prices of computing hardware is steadily dropping. The inventor of the PLC, Richard E Morley, fairly considers the PLC market as a 5-billion industry at the present time.Though PLCs are widely used in industrial practice, the programming of PLC based control systems is still very much relying on trial-and-error. Alike software engineering, PLC software design is facing the software dilemma or crisis in a similar way. Morley himself emphasized this aspect most forcefully by indicatingIf houses were built like software projects, a single woodpecker could d estroy civilization.”Particularly, practical problems in PLC programming are to eliminate software bugs and to reduce the maintenance costs of old ladderlogic programs. Though the hardware costs of PLC are dropping continuously, reducing the scan time of the ladder logic is still an issue in industry so that low-cost PLC can be used.In general, the productivity in generating PLC is far behind compared to other domains, for instance, VLSI design, where efficient computer aided design tools are in practice. Existent software engineering methodologies are not necessarily applicable to the PLC based software design because PLC-programming requires a simultaneous consideration of hardware and software. The software design becomes, thereby, more and more the major cost driver. In many industrial design projects, more than of the manpower allocated for the control system design and installation is scheduled for testing and debugging PLC programs.In addition, current PLC based control systems are not properly designed to support the growing demand for flexibility and reconfigurability of manufacturing systems. A further problem, impelling the need for a systematic design methodology, is the increasing software complexity in large-scale projects.The objective of this thesis is to develop a systematic software design methodology for PLC operated automation systems. The design methodology involves high-level description based on state transition models that treat automation control systems as discrete event systems, a stepwise design process, and set of design rules providing guidance and measurements to achieve a successful design. The tangible outcome of this research is to find a way to reduce the uncertainty in managing the control software development process, that is, reducing programming and debugging time and their variation, increasing flexibility of the automation systems, and enabling software reusability through modularity. The goal is to overcome shortcomings of current programming strategies that are based on the experience of the individual software developer. Three：now of PLCFrom the structure is divided into fixed PLC and Module PLC, the two kinds of PLC including CPU board, I/O board, display panel, memory block, power, these elements into a do not remove overall. Module type PLC including CPU module, I/O modules, memory, thepower modules, bottom or a frame, these modules can be according to certain rules combination configuration.In the user view, a detailed analysis of the CPU's internal unnecessary, but working mechanism of every part of the circuit. The CPU control works, by it reads CPU instruction, interprets the instruction and executes instructions. But the pace of work by shock signal control.Unit work under the controller command used in a digital or logic operations.In computing and storage register of computation result, it is also among the controller command and work. CPU speed and memory capacity is the important parameters fot PLC . its determines the PLC speed of work, IO PLC number and software capacity, so limits to control size.Central Processing Unit (CPU) is the brain of a PLC controller. CPU itself is usually one of the microcontrollers. Aforetime these were 8-bit microcontrollers such as 8051, and now these are 16-and 32-bit microcontrollers. Unspoken rule is that you’ll find mostly Hitachi and Fujicu microcontrollers in PLC controllers by Japanese makers, Siemens in European controllers, and Motorola microcontrollers in American ones. CPU also takes care of communication, interconnectedness among other parts of PLC controllers, program execution, memory operation, overseeing input and setting up of an output.System memory (today mostly implemented in FLASH technology) is used by a PLC for a process control system. Aside form. this operating system it also contains a user program translated foram ladder diagram to a binary form. FLASH memory contents can be changed only in case where user program is being changed. PLC controllers were used earlier instead of PLASH memory and have had EPROM memory instead of FLASH memory which had to be erased with UV lamp and programmed on programmers. With the use of FLASH technology this process was greatly shortened. Reprogramming a program memory is done through a serial cable in a program for application development.User memory is divided into blocks having special functions. Some parts of a memory are used for storing input and output status. The real status of an input is stored either as “1”or as “0”in a specific memory bit/each input or output has one corresponding bit in memory. Other parts of memory are used to store variable contents for variables used in used program. For example, time value, or counter value would be stored in this part of the memory.PLC controller can be reprogrammed through a computer (usual way), but also through manual programmers (consoles). This practically means that each PLC controller can programmed through a computer if you have the software needed for programming. Today’s transmission computers are ideal for reprogramming a PLC controller in factory itself. This is of great importance to industry. Once the system is corrected, it is also important to read the right program into a PLC again. It is also good to check from time to time whether program in a PLC has not changed. This helps to avoid hazardous situations in factory rooms (some automakers have established communication networks which regularly check programs in PLC controllers to ensure execution only of good programs).Almost every program for programming a PLC controller possesses various useful options such as: forced switching on and off of the system input/outputs (I/O lines), program follow up in real time as well as documenting a diagram. This documenting is necessary to understand and define failures and malfunctions. Programmer can add remarks, names of input or output devices, and comments that can be useful when finding errors, or with system maintenance. Adding comments and remarks enables any technician (and not just a person who developed the system) to understand a ladder diagram right away. Comments and remarks can even quote precisely part numbers if replacements would be needed. This would speed up a repair of any problems that come up due to bad parts. The old way was such that a person who developed a system had protection on the program, so nobody aside from this person could understand how it was done. Correctly documented ladder diagram allows any technician to understand thoroughly how system functions.Electrical supply is used in bringing electrical energy to central processing unit. Most PLC controllers work either at 24 VDC or 220V AC. On some PLC controllers you’ll find electrical supply as a separatemodule. Those are usually bigger PLC controllers, while small and medium series already contain the supply module. User has to determine how much current to take from I/O module to ensure that electrical supply provides appropriate amount of current. Different types of modules use different amounts of electrical current.This electrical supply is usually not used to start external input or output. User has to provide separate supplies in starting PLC controller inputs because then you can ensure so called “pure” supply for the PLC controller. With pure supply we mean supply where industrial environment can not affect it damagingly. Some of the smaller PLC controllers supply their inputs with voltage from a small supply source already incorporated into a PLC.Four：PLC design criteriaA systematic approach to designing PLC software can overcome deficiencies in the traditional way of programming manufacturing control systems, and can have wide ramifications in several industrial applications. Automation control systems are modeled by formal languages or, equivalently, by state machines. Formal representations provide a high-level description of the behavior of the system to be controlled. State machines can be analytically evaluated as to whether or not they meet the desired goals. Secondly, a state machine description provides a structured representation to convey the logical requirements and constraints such as detailed safety rules. Thirdly, well-defined control systems design outcomes are conducive to automatic code generation- An ability to produce control software executable on commercial distinct logic controllers can reduce programming lead-time and labor cost. In particular, the thesis is relevant with respect to the following aspects.In modern manufacturing, systems are characterized by product and process innovation, become customer-driven and thus have to respond quickly to changing system requirements. A major challenge is therefore to provide enabling technologies that can economically reconfigure automation control systems in response to changing needs and new opportunities. Design and operational knowledge can be reused inreal-time, therefore, giving a significant competitive edge in industrial practice.Studies have shown that programming methodologies in automation systems have not been able to match rapid increase in use of computing resources. For instance, the programming of PLC still relies on a conventional programming style with ladder logic diagrams. As a result, the delays and resources in programming are a major stumbling stone for the progress of manufacturing industry. Testing and debugging may consume over 50% of the manpower allocated for the PLC program design. Standards [IEC 60848, 1999; IEC-61131-3, 1993; IEC 61499, 1998; ISO 15745-1, 1999] have been formed to fix and disseminate state-of-the-art design methods, but they normally cannot participate in advancing the knowledge of efficient program and system design.A systematic approach will increase the level of design automation through reusing existing software components, and will provide methods to make large-scale system design manageable. Likewise, it will improve software quality and reliability and will be relevant to systems high security standards, especially those having hazardous impact on the environment such as airport control, and public railroads.The software industry is regarded as a performance destructor and complexity generator. Steadily shrinking hardware prices spoils the need for software performance in terms of code optimization and efficiency. The result is that massive and less efficient software code on one hand outpaces the gains in hardware performance on the other hand. Secondly, software proliferates into complexity of unmanageable dimensions; software redesign and maintenance-essential in modern automation systems-becomes nearly impossible. Particularly, PLC programs have evolved from a couple lines of code 25 years ago to thousands of lines of code with a similar number of 1/O points. Increased safety, for instance new policies on fire protection, and the flexibility of modern automation systems add complexity to the program design process. Consequently, the life-cycle cost of software is a permanently growing fraction of the total cost. 80-90% of these costs are going into software maintenance, debugging, adaptation and expansion to meet changing needs.Today, the primary focus of most design research is based on mechanical or electrical products. One of the by-products of this proposed research is to enhance our fundamental understanding of design theory and methodology by extending it to the field of engineering systems design. A system design theory for large-scale and complex system is not yet fully developed. Particularly, the question of how to simplify a complicated or complex design task has not been tackled in a scientific way. Furthermore, building a bridge between design theory and the latest epistemological outcomes of formal representations in computer sciences and operations research, such as discrete event system modeling, can advance future development in engineering design.From a logical perspective, PLC software design is similar to the hardware design of integrated circuits. Modern VLSI designs are extremely complex with several million parts and a product development time of 3 years [Whitney, 1996]. The design process is normally separated into a component design and a system design stage. At component design stage, single functions are designed and verified. At system design stage, components are aggregated and the whole system behavior and functionality is tested through simulation. In general, a complete verification is impossible. Hence, a systematic approach as exemplified for the PLC program design may impact the logical hardware design.可编程控制器一、PLC概述可编程控制器是60年代末在美国首先出现的，当时叫可编程逻辑控制器PLC（Programmable Logic Controller），目的是用来取代继电器。
PLC电梯控制英文文献(3600英词)
The Programmable Logic ControllerJohn R. Hackworth, Frederick D. Hackworth, Jr.Programmable Logic Controllers: Programming Methods and Applications.2.5~2.8,The Programmable Logic Controller,John R. Hackworth, Frederick D. Hackworth, Jr.First Edition. London: Prentice Hall,2003.35~501.1 System Block DiagramA Programmable Controller is a specialized computer. Since it is a computer, it has all the basic component parts that any other computer has; a Central Processing Unit, Memory, Input Interfacing and Output Interfacing. A typical programmable controller block diagram is shown in Figure 2.5.Figure 2.5 Programmable Controller Block DiagramThe Central Processing Unit (CPU) is the control portion of the PLC. It interprets the program commands retrieved from memory and acts on those commands. In present day PLC's this unit is a microprocessor based system. The CPU is housed in the processor module of modularized systems.Memory in the system is generally of two types; ROM and RAM. The ROM memorycontains the program information that allows the CPU to interpret and act on the Ladder Logic program stored in the RAM memory. RAM memory is generally kept alive with an on-board battery so that ladder programming is not lost when the system power is removed.This battery can be a standard dry cell or rechargeable nickel-cadmium type. Newer PLC units are now available with Electrically Erasable Programmable Read Only Memory (EEPROM) which does not require a battery. Memory is also housed in the processor module in modular systems.Input units can be any of several different types depending on input signals expected as described above. The input section can accept discrete or analog signals of various voltage and current levels. Present day controllers offer discrete signal inputs of both AC and DC voltages from TTL to 250 VDC and from 5 to 250 VAC. Analog input units can accept input levels such as ±10 VDC, ±5 VDC and 4-20 ma. current loop values. Discrete input units present each input to the CPU as a single 1 or 0 while analog input units contain analog to digital conversion circuitry and present the input voltage to the CPU as binary number normalized to the maximum count available from the unit. The number of bits representing the input voltage or current depends upon the resolution of the unit. This number generally contains a defined number of magnitude bits and a sign bit. Register input units present the word input to the CPU as it is received (Binaryor BCD).Output units operate much the same as the input units with the exception that the unit is either sinking (supplying a ground) or sourcing (providing a voltage) discrete voltages or sourcing analog voltage or current. These output signals are presented as directed by theCPU. The output circuit of discrete units can be transistors for TTL and higher DC voltage or Triacs for AC voltage outputs. For higher current applications and situations where a physical contact closure is required, mechanical relay contacts are available. These higher currents, however, are generally limited to about 2-3 amperes. The analog output units have internal circuitry which performs the digital to analog conversion and generates the variable voltage or current output.1.2 Update - Solve the Ladder - UpdateWhen power is applied to a programmable logic controller, the PLC’s operation consists of two steps: (1) update inputs and outputs and (2) solve the ladder. This may seem like a very simplistic approach to something that has to be more complicated but there truly are only these two steps.If these two steps are thoroughly understood, writing and modifying programs and getting the most from the device is much easier to accomplish. With this understanding, the things that can be undertaken are then up to the imagination of the programmer.You will notice that the “update - solve the ladder” sequence begins after startup. The actual startup sequence includes some operations transparent to the user or programmer that occur before actual PLC operation on the user program begins. During this startup there may be extensive diagnostic checks performed by the processor on things like memory, I/O devices, communication with other devices (if present) and program integrity. In sophisticated modular systems, the processor is able to identify the various module types, their location in the system and address. This type of system analysis and testing generally occurs during startup before actual program execution.1.3 UpdateThe first thing the PLC does when it begins to function is update I/O. This means that all discrete input states are recorded from the input unit and all discrete states to be output are transferred to the output unit. Register data generally has specific addresses associated with it for both input and output data referred to as input and output registers. These registers are available to the input and output modules requiring them and are updated with the discrete data. Since this is input/output updating, it is referred to as I/O Update. The updating of discrete input and output information is accomplished with the use of input and output image registers set aside in the PLC memory. Each discrete input point has associated with it one bit of an input image register. Likewise, each discrete output point has one bit of an output image register associated with it. When I/O updating occurs, each input point that is ON at that time will cause a 1 to be set at the bit address associated with that particular input. If the input is off, a 0 will be set into the bit address. Memory in today's PLC's is generally configured in 16 bit words. This means that one word of memory can store the states of 16 discrete input points.Therefore, there may be a number of words of memory set aside as the input and output image registers. At I/O update, the status of the input image register is set according to the state of all discrete inputs and the status of the output image register is transferred to the output unit.This transfer of information typically only occurs at I/O update. It may be forced to occur at other times in PLC's which have an Immediate I/O Update command. This command will force the PLC to update the I/O at other times although this would be a special case.One major item of concern about the first output update is the initial state of outputs.This is a concern because their may be outputs that if initially turned on could create a safety hazard, particularly in a system which is controlling heavy mechanical devices capable of causing bodily harm to operators. In some systems, all outputs may need to be initially set to their off state to insure the safety of the system. However, there may be systems that require outputs to initially be set up in a specific way, some on and some off. This could take the form of a predetermined setup or could be a requirement that the outputs remain in the state immediately before power-down. More recent systems have provisions for both setup options and even a combination of the two. This is a prime concern of the engineer and programmer and must be defined as the system is being developed to insure the safety of personnel that operate and maintain the equipment. Safety as related to system and program development will be discussed in a later chapter.1.4 Solve the LadderAfter the I/O update has been accomplished, the PLC begins executing the commands programmed into it. These commands are typically referred to as the ladder diagram. The ladder diagram is basically a representation of the program steps using relay contacts and coils. The ladder is drawn with contacts to the left side of the sheet and coils to the right.This is a holdover from the time when control systems were relay based.This type of diagram was used for the electrical schematic of those systems.A sample ladder diagram is shown in Figure 2-6.Figure 2-6 Sample Ladder DiagramThe symbols used in Figure 2.6 may be foreign at this point, so a short explana ---tion will be necessary. The symbols at the right of the ladder diagram labeled CR1, CR2, CR3 and CR4 and are circular in shape are the software coils of the relays. The symbols at the left which look like capacitors, some with diagonal lines through them , are the contacts associated with the coils. The symbols that look like capacitors with --out the diagonal lines through them are normally open contacts. These are analogous to a switch that is normally off. When the switch is turned on, the contact closes. The contact symbols at the left that look like capacitors with diagonal lines through them are normally closed contacts. A normally closed contact is equivalent to a switch that is normally turned on. It will turn off when the switch is actuated.As can be seen in Figure 2.6, contact and coil position is as described above. Also, one can see the reason for the term ladder diagram if the rungs of a stepladder are visualized. In fact, each complete line of the diagram is referred to as one rung of logic. The actual interpretation of the diagram will also be discussed later although some explanationis required here.The contact configuration on the left side of each rung can be visualized as switches and the coils on the right as lights.If the switches are turned on and off in the proper configuration, the light to the right will illuminate.The PLC executes this program from left to right and top to bottom, in that order.It first looks at the switch (contact) configuration to determine if current can be passed to the light (coil).The data for this decision comes from the output and input image registers.If current can be passed, the light (coil) will then be turned on.If not, the light (coil) will be turned off.This is recorded in the output image register Once the PLC has looked at the left side of therung it ignores the left side of the rung until the next time it solves that particular rung. Once the light (coil) has been either turned on or off it will remain in that state until the next time the PLC solves that particular rung.After solving a rung, the PLC moves on to solve the next rung in the same manner and so forth until the entire ladder has been executed and solved.One rule that is different from general electrical operation is the direction of current flow in the rung.In a ladder logic, rung current can only flow from left to right and up and down; never from right to left.As an example, in the ladder shown in Figure 2.7, coil CR1 will energize if any of thefollowing conditions exist:Figure 2.7 Illustration of allowed current flow in ladder rung1. CR7 is off, CR6 is on.2. CR7 is off, CR2 is on, CR5 is on.3. CR7 is off, CR2 is on, CR3 is on.4. CR1 is on, CR4 is on, CR3 is on.5. CR1 is on, CR4 is on, CR5 is on.You will notice that the current flow in the circuit in each of the cases listed above is from left to right and up and down. CR1 will not energize in the case listed below: CR1 is on, CR4 is on, CR2 is on, CR6 is on, CR5 is off, CR3 is off, CR7 is on.This is because current would have to flow from right to left through the CR2 contact. This is not allowed in ladder logic even though current could flow in this direction if we were to build it with real relays.Remember, we are working in the software world not the hardware world.To review, after the I/O update, the PLC moves to the first rung of ladder logic.It solves the contact configuration to determine if the coil is to be energized or de-energized.It then energizes or de-energizes the coil.After this is accomplished, it moves to the left side of the next rung and repeats the procedure.This continues until all rungs have been solved. When this procedure is complete with all rungs solved and all coils in the ladder set up according to the solution of each rung, the PLC proceeds to the next step of it's sequence, the I/O update.At I/O update, the states of all coils which are designated as outputs are transferred from the output image register to the output unit and the states of all inputs are transferred to the input image register.Note that any input changes that occur during the solution of the ladder are ignored because they are only recorded at I/O update time.The state of each coil is recorded to the output image register as each rung is solved. However, these states are not transferred to the output unit until I/O update time.Figure2.8 Scan CycleThis procedure of I/O update and solving the ladder diagram and I/O update is referred to as scanning and is represented in Figure 2.8. The period between one I/O update and the next is referred to as one Scan.The amount of time it takes the PLC to get from one I/O update to the next is referred to as Scan Time.Scan time is typically measured in milliseconds and is related to the speed of the CPU and the length of the ladder diagram that has to be solved .The slower the processor or the longer the ladder diagram, the longer the scan time of the system.The speed at which a PLC scans memory is referred to as Scan Rate.Scan rate units are usually listed in msec/K of memory being utilized for the program.As an example, if a particular PLC has a rated scan rate of 8 msec/K and the program occupies 6K of memory, it will take the PLC 48 msec to complete one scan of the program.1.5.MotivationProgrammable Logic Controllers (PLC), a computing device invented by Richard E. Morley in 1968, have been widely used in industry including manufacturing systems, transportation systems, chemical process facilities, and many others. At that time, the PLC replaced thehardwired logic with soft-wired logic or so-called relay ladder logic (RLL), aprogramming language visually resembling the hardwired logic, and reduced thereby the configuration time from 6 months down to 6 days [Moody and Morley, 1999 Although PC based control has started to come into place, PLC based control will remain the technique to which the majority of industrial applications will adhere due to its higher perfor- mance, lower price, and superior reliability in harsh environments. Moreover, according to a study on the PLC market of Frost and Sullivan [1995], an increase of the annual sales volume to 15 million PLCs per year with the hardware value of more than 8 billion US dollars has been predicted, though the prices of computing hardware is steadily dropping. The inventor of thePLC, Richard E Morley, fairly considers the PLC market as a5-billion industry at the present time.Though PLCs are widely used in industrial practice, the programming of PLC based control systems is still very much relying on trial-and-error. Alike software engineering, PLC software design is facing the software dilemma or crisis in a similar way. Morley himself emphasized this aspect most forcefully by indicating [Moody and Morley, 1999, p. 110“If houses were built like soft ware projects, a single woodpecker could destroy civilization.”Particularly, practical problems in PLC programming are to eliminate software bugs and to reduce the maintenance costs of old ladder logic programs. Though the hardware costs of PLCs are dropping continuously, reducing the scan time of the ladder logic is still an issue in industry so that low-cost PLCs can be used.In general, the productivity in generating PLC is far behind compared to other domains, for instance, VLSI design, where efficient computer aided design tools are in practice. Existent software engineering methodologies are not necessarily applicable to the PLC based software design because PLC-programming requires a simultaneous consideration ofhardware and software. The software design becomes, thereby, more and more the major cost driver. In many industrial design projects, more than SO0/a of the manpower allocated for the control system design and installation is scheduled for testing and debugging PLC programs [Rockwell, 1999].In addition, current PLC based control systems are not properly designed to support the growing demand for flexibility and reconfigurability of manufacturing systems. A further problem, impelling the need for a systematic design methodology, is the increasing software complexity in large-scale projects1.6.Objective and Significance of the ThesisThe objective of this thesis is to develop a systematic software design methodology for PLC operated automation systems. The design methodology involves high-level description based on state transition models that treat automation control systems as discrete event systems, a stepwise design process, and set of design rules providing guidance and measurements to achieve a successful design. The tangible outcome of this research is to find a way to reduce the uncertainty in managing the control software development process, hat is, reducing programming and debugging time and their variation, increasing flexibility of the automation systems, and enabling software reusability through modularity. The goal is to overcome shortcomings of current programming strategies that are based on the experience of the individual software developerDesign Theory DevelopmentToday, the primary focus of most design research is based on mechanical or electrical products. One of the by-products of this proposed research is to enhance our fundamental understanding of design theory and methodology by extending it to the field of engineeringsystems design. A system design theory for large-scale and complex system is not yet fully developed. Particularly, the question of how to simplify a complicated or complex design task has not been tackled in a scientific way. Furthermore, building a bridge between design theory and the latest epistemological outcomes of formal representations in computer sciences and operations research, such as discrete event system modeling, can advance future development in engineering designApplication in Logical Hardware DesignFrom a logical perspective, PLC software design is similar to the hardware design of integrated circuits. Modern VLSI designs are extremely complex with several million parts and a product development time of 3 years [Whitney, 1996]. The design process is normally separated into a component design and a system design stage. At component design stage, single functions are designed and verified. At system design stage, components are aggregated and the whole system behavior and functionality is tested through simulation. In general, a complete verification is impossible. Hence, a systematic approach as exemplified for the PLC program design may impact the logical hardware designPLCPLC （programmable logical controller ）face ever more complex challenge these days. Where once they quietly relays and gave an occasional report to a corporate mainframe, they are now grounded into cells, give new jobs and new languages, and are forced to compete against a growing array of control products. For this year ’s annual PLC technology update, we queried PLC makers on these topics and moreProgramming languagesHigher level PLC programming languages have been around for some time, but latelytheir popularity has been mushrooming. As Raymond Lavelle, vice president and general manager, Siemens Energy and Automation. Inc, Programmable Controls Division, points out : ” As programmable controls are being used for more and more sophisticated operations, languages other than ladder logic become more practical, efficient, and powerful. For example, it's very difficult to write a trigonometric function using ladder logic. ” Languages gaining acceptance include Boolean, control system flowcharting, and such function chart languages as Graphtec and its variations. And these’s increasing interest in languages like C and BASIC.PLCs in process control Thus far, PLCs have not been used extensively for continuous process control. Will this continue? ”The feeling that I ’ve gotten, ” says Ken Jeannette, manager, product planning, Series One and Series Six products, at GE Frame North America, "is that PLCs will be used in the process industry but not necessarily for process control.”Several vendors-obviously betting that the opposite will happen-have introduced PLCs optimized for process applications. Rich Ryan ,manager, commercial marketing, Allen-Bradley Programmable Controls Div, cites PLCs ’ increasing use in such industries as food, chemicals,and petroleum. Ryan feel there are two types of applications in which they’re appropriate.”One,"he says, "is where the size of the process control system that's being automated doesn’t justify DCS[distributed control systems].With the starting price tags of those products being relatively high, a programmable controller makes sense for small, low loop count applications. The seconds where you have to integrate the loop closely with the sequential logic. Batch controller sere prime examples, where the sequence and maintaining the process variable are intertwined so closely that the benefits of having a programmable controller to do the sequential logic outweighs someof the disadvantages of not having a distributed control system.”Bill Barkovtz, president of Triconex, predicts that "all future controllers that come out in the process control system business will embrace a lot more PLC technology and a lot more PLC functionality than they ever did before.”中文翻译可编程逻辑控制器约翰R Hackworth，弗雷德里克 D Hackworth.可编程逻辑控制器：编程方法及应用.2.5~2.8，可编程逻辑控制器，约翰R Hackworth，弗雷德里克 D Hackworth第一版. 伦敦:普伦蒂斯霍尔出版社,2003,35~50一系统框图可编程控制器是一种专用的计算机。
自动化专业-外文文献-英文文献-外文翻译-plc方面
1、外文原文（复印件)A: Fundamentals of Single-chip MicrocomputerTh e si ng le-ch i p mi cr oc om pu ter is t he c ul mi nat i on o f bo th t h e d ev el op me nt o f th e d ig it al com p ut er an d t he int e gr at ed ci rc ui ta r gu ab ly th e t ow m os t s i gn if ic ant i nv en ti on s o f t h e 20t h c en tu ry[1].Th es e to w t ype s o f a rc hi te ct ur e a re fo un d i n s i ng le—ch ip m i cr oc om pu te r。
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外文翻译---基于PLC电梯控制系统的设计与实践
翻译部分英文原文Design and Practice of an Elevator Control System Based on PLCAbstractThis paper describes the development of 2 nine-storey elevators control system for a residential building.The control system adopts PLC as controller,and uses a parallel connection dispatching rule based on"minimum waiting time"to run 2 elevators in parallel mode.The paper gives the basic structure,control principle and realization method of the PLC control system in detail. It also presents the ladder diagram of the key aspects of the system.The system has simple peripheral circuit and the operation result showed that it enhanced the reliability and performance of the elevators.1.IntroductionWith the development of architecture technology,the building is taller and tallerand elevators become important vertical transportation vehicles in high-rise buildings.They are responsible to transport passengers, living,working or visiting in the building,comfortable and efficiently to their destinations.So the elevator control system is essential in the smooth and safe operation of each elevator.It tells the elevator in what order to stop at floors,when to open or close the door and if there is a safety-critical issue.The traditional electrical control system of elevators is a relay-controlled system.It has the disadvantages such as complicated circuits,high fault ratio and poor dependability;and greatly affects the elevator’s running quality.Therefore,entrusted byan enterprise,we have improved electrical control system of a relay-controlled elevator in a residential building by using PLC.The result showed that the reformed system is reliable in operation and easy for maintenance.This paper introduces the basic structure,control principle and realization method of the elevator PLC control system in detail.2.System structureThe purpose of the elevator control system is to manage movement of an elevator in response to user’s requests.It is mainly composed of 2 parts:2.1.Electric power driving systemThe electric power driving system includes:the elevator car,the traction motor,door motor,brake mechanism and relevant switch circuits.Here we adopted a new type of LC series AC contactors to replace the old ones,and used PLC’s contacts to substitute the plenty of intermediate relays. The circuits of traction motor are reserved.Thus the original control cabinet’s disadvantages,such as big volume and high noise are overcome efficiently.2.2.Signal control systemThe elevator’s control signals are mostly realized by PLC.The input signals are:operation modes,operation control signals,car-calls,hall-calls,safety/protect signals, door open/close signal and leveling signal,etc.All control functions of the elevator system are realized by PLC program,such as registration,display and elimination of hall-calls or car-calls,position judgment of elevator car, choose layer and direction selection of the elevator,etc.The PLC signal control system diagram of elevator is showed in Figure 1.Figure 1 PLC signal control system diagram2.3.RequirementsThe goal of the development of the control system is to control 2 elevators in a 9-storey residential building.For each elevator,there is a sensor located at every floor.We can use these sensors to locate the current position of the elevator car.The elevator ar door can be opened and closed by a door motor.There are 2 sensors on the door that can inform the control system about the door’s position.There is another sensor on the door can detect objects when the door is closing.The elevator car’s up or down movement is controlled by a traction motor.Every floor,except the first and the top floor,has a pair of direction lamps indicating that the elevator is moving up or down.Every floor,has a seven segment LED to display the current location of the elevator car.The first step for the development of the elevator control is to define the basic rmally,the elevators behavior is defined as follows.(1)Running with a single elevatorGenerally,an elevator has three operation states: normal mode,fire-protection mode and maintenance mode.The maintenance mode has the highest priority. Only the maintenance mode is canceled can the other operation modes be implemented.The next is fire-protection mode,the elevator must return to the bottom floor or base station immediately when the fire switch acts.The elevator should turn to normal operation mode when the fire switch is reset.Under normal operation mode,the control system’s basic task is to command each elevator to move up or down,to stop or start and to open and close the door.But is has some constraints as follows: Each elevator has a set of 9 buttons on the car control panel,one for each floor.These buttons illuminate when they are pressed and cause the elevator to visit the corresponding floor.The illumination is canceled when the corresponding floor is visited by the elevator.Each floor,except the first and the top floor,has two buttons on the floor control panel,one to request an up- elevator,one to request a down-elevator.These buttons illuminate when they are pressed.The illumination is canceled when an elevator visits the floor,then moves in the desired direction.The buttons on the car control panel or the floor control panel are used to control the elevator’s motion.The elevator cannot pass a floor if a passenger wants to get off there.The elevator cannot stop at a floor unless someone wants to get off there.The elevator cannot change direction until it has served all onboard passengers traveling in the current direction, and a hall call cannot be served by a car going in the reverse direction.If an elevator has no requests,it remains at its current floor with its doors closed.(2)Parallel running with two elevatorsIn this situation,there are two elevators to serve the building simultaneously.It runs at 7am to 9am and 5pm to 7pm every day.When an elevator reaches a level,it will test if the stop is required or not.It will stop at this level when the stop is required.At the same time,to balance the number of stops,the operation of two elevators will follow a certain dispatching principle.An elevator doesn’t stop at a floor if another car is already stopping,or has been stopped there.The normal operation of elevators is implemented by cooperation of its electric power driving system and logic control system.3.Software designDue to the random nature of call time,call locations and the destination of passengers,the elevator control system is a typical real-time,random logic control system. Here we adopted collective selective control method with siemens PLC S7-200 CPU226 and its extension modules. There are 46 input points and 46 output points in the system.The I/O points are showed in Table1 and Table 2.Table 1 Input pointsTable 2 Output pointsAbout software designing,we adopt the modularized method to write ladder diagram programs.The information transmission between modules is achieved by intermediate register bit of PLC.The whole program is mainly composed of 10 modules: hall-call registration and display module,car-call registration and display module,the signal combination module,the hall-call cancel module,the elevator-location display module,the floor selection module,the moving direction control module,the door open/close module,the maintenance operation module and the dispatching module under parallel running mode.The design of the typical modules is described as follows:3.1.Hall-call registration and displayThere are two kinds of calls in an elevator:hall-call and car-call.When someone presses a button on the floor control panel,the signal will be registered and the corresponding lamp will illuminate.This is called hall-call registration.When a passenger presses a button in the elevator car, the signal will be registered and with the corresponding lamp illuminated.This is called car-call registration.Figure2 shows the ladder diagram of up hall-calls registration and display.The self-lock principle is used to guarantee the calls’continuous display.Figure 2 up hall-call registration and display3.2.The collective selection of the callsHere the collective selection control rules are used.As showed in Figure3,M5.1-M5.7,M6.0 and M6.1 are auxiliary relays in PLC.They denote the stopping request signal of 1st to 9th floor respectively.The auxiliary relay M6.2 denotes the elevator driver’s operation signal.When there is a call in a certain floor,the stopping signal of corresponding floor will output.When the elevator is operated by the driver,the hall-calls will not be served. And the elevator cannot pass a floor at which a passenger wishes to alight.3.3.The cancellation of the callsThe program of this module can make the elevator response the hall-calls which have the same direction as the car’s current direction,and when a hall-call is served, its registration will be canceled.The ladder diagram of up hall-calls’cancellation is showed in Figure4.Figure 3 The combination of the callsFigure 4 The cancellation of up callsIn Figure4,the auxiliary relay M4.0 is the up moving flag of the elevator.When the current direction of the elevator is up,M4.0’s contacts are closed;on the contrary, when the current direction of the elevator is down,M4.0’s contacts are opened.M0.1 to M0.7 denotes the car-calls’ stopping request signal of floor 2 to floor 8 respectively.This program has two functions:(1)Make the elevator response the normal down hall-calls when it is moving down,and when a down hall-call is served,its registration is canceled.(2)When the elevator is moving up,the corresponding floor’s down hall-call it passing by is not served and the registration is remained.The cancellation of down hall-calls is reversed with up hall-calls.3.4.Elevator’s directionThe elevator may be moving up or down,depending on the combination of hall-calls and car-calls.The following ladder diagram in Fig.5 illustrates that the elevator will move up.Figure 5 Up moving of the elevatorFigure5 shows that when the calls corresponding floor is higher than the elevator’s current location,the el evator will go up.Here the auxiliary relay M4.0 is used as the up-moving flag.When the elevator is moving up,the up-moving lamp is illuminated,so the M4.0 is connectedon.When the elevator arrives the top floor,the up-moving lamp is off and the timer starts.After 0.2s,the M4.0 is disconnected,the up-moving display is off.Here we used M4.0 to replace Q3.1 which can ensure the cancellation’s reliability.3.5.Elevator’s floor-stoppingFigure6 shows the ladder diagram of the elevator’s floor-stopping function.As showed in Figure6,M6.4 is the flag of floor-stopping signal.M6.6 is the floor-stopping signal sent by the driver.M7.0 is the fire signal sent by the fire switch.And M6.7 is the forced speed changing signal. When either of these contacts act,the system should send out the floor-stopping signal.4.Minimum waiting time algorithmIn traffic of elevator systems,there are two types of control task usually.The one is the basic control function to command each elevator to move up or down,to stop or start and to open and close the door.The other is the control of a group of elevators.The main requirements of a group control system in serving both,car and hall calls,should be:to provide even service to every floor in a building;to minimize the time spent by passengers waiting for service;to minimize the time spent by passengersto move from one floor to another;to serve as many passengers as possible in a given time[1].Figure 6 The elevator’s floor-stoppingThere are many dispatching algorithms for elevator’s group control.Such as Nearest-neighbor Algorithm[2], which the elevator always serve the closet request next; Zoning Algorithm[3] which by analyzing the traffic of elevator system with unequal floor and population demand to dispatch the elevator;and Odd-even rule, which an elevator only serves the odd floor and the other only serves the even floor.The Nearest-neighbor Algorithm minimizes the length of the elevator’s empty move to the next request.it usually has very small average waiting times,but individual waiting times can become quite large[2].The Zoning Algorithm usually used in buildings which has heavy traffic situations,such as the office building at lunch time.Compared to the office building and shopping mall, the traffic flow of residential buildings is relatively low and even in every floor.Secondly,people usually think of elevators as purely functional objects and the experience of riding an elevator is time waited for most of them. Furthermore,there exist immense problems when attempting to satisfy all requirements.Considering all of the reasons above,we adopted the “minimum waiting time”algorithm to realize the 2elevators’parallel running[4].4.1.Evaluation functionThe goal of the“minimum waiting time”algorithm is to predict the each elevator’s response time according to all calls,and select the elevator which has the shortest response time to serve.When there is a call,the system calculates out the function values of each elevator according the evaluation function showed in(1)and(2):J(*)=Min[J(1),J(2),…,J(n)](1)J(i)=Tr(i)+KTd(i)+KTo(i)i=1,2,...,n (2)J(i)is the evaluation index of each elevator;Tr(i) denotes the time of the elevator directly moving to the destination corresponding the latest call from its current floor;To(i)denotes the additional acceleration and deceleration time of a floor-stop of the elevator;Td(i) denotes the average time of the passenger boarding and alighting the elevator;and K is the sum of hall-calls and car-calls.But when a hall-call and a car call corresponds the same floor,the K is only calculated one time.4.2.Calculation of minimum waiting timeIn equation(2),K is a certain value,To and Td can be obtained by means of statistics.Tr=T*L,where T denotes the average time of the elevator passing by one floor;L denotes the desired floors of the elevator from current floor to the hall-call floor.In order to calculate the L value,we defined the 2 elevators are A and B respectively;YA,YB denotes the current floor of elevator A and B respectively.H is the corresponding key value when a hall-call button is pressed,and H=floor number of the hall-call.We defined 4 tables for the PLC realization:up hall-call registration table,down hall-call registration table,car-call registration table of A and car-call registration table of B.When a certain call button is pressed,its floor value is recorded in corresponding table.Here we take elevator A as an example.First,define the variable MA,MB and MW.Where MA,MB denotes the extreme value of car-calls with same direction of A or B’s movement respectively.When elevator A is up-moving,set MA is equal to the maximum value in car-call registration table A;when elevator A is down-moving,set MA is equal to the minimum value in car-call registration table A.MW denotes the extreme value of hall-calls with same direction of A’s movement.When elevator A is up-moving and up-hall-call value≥YA,set MW=0;otherwise,set MW is equal to the minimum value in up-hall-call registrationtable A.When elevator A is down-moving and up-hall-call value≤YA,set MW=0;otherwise,set MW is equal to the maximum value in down-hall-call registration table A.Thus,we can determine the L value according to YA,H, MA and MW.There are 3 situations:(1)When the hall-call’s direction is opposite to ele vator A’s movement:L=|YA-MA|+|MA-H|(3)(2)When the hall-call’s direction is same as elevator A’s movement and it is in the front of elevator A:L=|YA-H|(4)(3)When the hall-call’s direction is same as the elevator A’s movement and it is in the back of elevator A:L=|YA-MA|+|MA-MW|+|H-MW|(5)So the i-th floor’s minimum waiting time can be calculated by(6)as follows:Time(i)=TL(i)+KTd(i)+KTo(i)i=1,2,...,n(6)When the calls change during the operation of elevators,the system calculates the minimum waiting time of each elevator.Then it allocates the current call to the elevator which has small value.When the each elevator has the same value,then the current call is prior to elevator A.When an elevator is wrong or not in service,the system can exit the dispatching algorithm and turns to a single elevator running mode.4.3.Algorithm realizationCompared with single elevator running mode,the parallel running mode is mainly different at the processing method about hall-calls.The former uses collective selective control method,and the latter uses dispatch rule combined with collective selective control method.Here the system is to control a 9-storey building,so we choose two Siemens S7-200 PLCs(CPU226)and its Extensive Modules to control the single elevator respectively.And by using PPI Protocol to realize the communication between 2 PLCs.The PPI Protocol adopts master-slave communication mode,so we defined elevator A as the master and elevator B as the slave.By communication program,the 2 PLCs can exchange the massage such as the current position, hall-calls or car-calls and moving direction.Then by using“minimum waiting time”algorithm,the system realizes the optimal operation of 2 elevators.Figure7 shows the ladder program of the car-calls extreme value calculation of elevator A.In Figure7,VB121～VB130 is the register address of elevator A’s car-call corresponding to each floor,Q3.1 is the up-moving lamp of elevator A,and the car-calls extreme value issaved in VB120.Figure 7 The car-calls extreme value calculation of elevator A5.ConclusionsIn this paper,we have improved an old elevator control system by using PLC,and realized the group control of 2 elevators.The new control system has been operated for 1 year,and its operation scenarios are as follows:(1)Down–PeakThis traffic condition concerns people out of the building in the morning between 7am to 9am.(2)Up–PeakThis condition concerns people entering the building between 5pm to 7pm.(3)OtherIt covers the day from 6:00 to 0:00 except the two situations above.And in this situation,there is only one elevator running.The results are expressed via an average waiting time and maximum waiting time(both given in seconds)are collected in Tables 3 and 4.Table 3Average and maximum waiting time(before reformed)Due to the nonparallel running before the reform,so the average waiting time and maximum waiting time of down–peak and the up–peak are very longer than the reformed.The practice results have showed the better performance of the improved control system.References[1]Ricardo Gudwin,Fernando Gomide,Marcio(1998).“A Fuzzy Elevator Group Controller With Linear Context Adaptation”.IEEE World Congress on Computational Intelligence.V ol.12,No.5,pp.481-486.[2]Philipp Friese,Jorg Rambau(2006).“On line-optimization of multi-elevator transport systems with reoptimization algorithms based on set-partitioning models”.Discrete Applied Mathematics.No.154,pp.1908-1931.[3]Zheng Yanjun,Zhang Huiqiao,Ye Qingtai,Zhu Changming.(2001).“The Research on Elevator Dynamic Zoning Algorithm and It's Genetic Evolution”.Computer Engineering and Applications,No.22,pp.58-61.[4]Xiaodong Zhu,Qingshan Zeng(2006).“A Elevator Group Control Algorithm for Minimum Waiting Time Based On PLC”.Journal of Hoisting and Conveying Machiner,No.6, pp.38-40中文译文基于PLC电梯控制系统的设计摘要本文介绍了二组9层电梯的住宅楼宇控制系统的发展。
基于plc电梯控制外文文献翻译、中英文翻译、外文翻译
In the article has analyzed the elevator loadcharacteristics, elaborated uses the trapezoid acceleration curve theelevator ideal velocity curve, unifies the frequency changer and thePLC performance, elaborated the elevator control system constitutionand the operational factor. Elaborated the elevator speed curveproduces the method, has induced the characteristic which designs byPLC constitution control system software.Key word: Load characteristics ideal velocity curve control systemsoftware design1. OutlineAlong with the urban construction unceasing development, thehigh-rise construction unceasingly increases, the elevator has thewidespread application in the national economy and the life. Theelevator took in the high-rise construction the vertical movementtransportation vehicle already and people's daily life is inseparable.In fact the elevator is according to exterior movement and so oncalling signal as well as own control rule, but calls is stochastic,the elevator is a person machine interactive control system in fact,purely is cannot satisfy the control request with the sequentialcontrol or the logical control, Therefore, the elevator control system uses the stochastic logical waycontrol. At present the elevator control generally has selected twomethods, one is uses the microcomputer to take the signal controlunit, completes the elevator signal gathering, the running status andthe function hypothesis, realizes the elevator automatic dispatch andthe collection chooses the movement function, drives the control tocomplete by the frequency changer; The second control mode (PLC)substitutes for the microcomputer realization signal collection withthe programmable controller to choose the control. Said from the control mode and the performance, these two methodscertainly not too big difference. The domestic factory mostly choosesthe second way, its reason lies in the production scale slightly, owndesign and the manufacture microcomputer control device cost ishigher; But PLC reliability high, programming convenience nimble, theantijamming ability strong, the movement stable is reliable and so onthe characteristic, therefore the present elevator control systemwidely uses the programmable controller to realize.2. Elevator ideal performance diagramIndicated according to the massive research and the experiment, theperson may accept the maximum acceleration is am <= 1.5m/s2,acceleration rate of change rho m <= the 3m/s3, elevator idealperformance diagram may divide according to the acceleration is thetriangle, the trapezoid and the sine profile, As a result of sine profile acceleration curve realization moredifficult, but the triangle curve maximum acceleration and is startingand applies the brake the section turning point acceleration rate ofchange to be bigger than the trapezoidal curve, namely + rho m jumpsto - rho m or jumps from - rho m to + rho the m acceleration rate ofchange, therefore very little uses, because the trapezoidal curve iseasy to realize and has the good acceleration rate of change frequenttarget, therefore is widely used, uses the trapezoidal accelerationcurve elevator ideal performance diagram like chart 1 to show: The intelligent frequency changer is for the elevator special-purposefrequency changer request and so on elevator nimble velocitymodulation, control and high accuracy even level which but speciallydesigns, may use for parts the general three-phase asynchronous motor,and has function and so on intellectualized software, standardconnection, menu prompt, input elevator curve and other essentialparameter. It has the debugging convenience quickly, moreover can automaticallyrealize the single multilayered function, and has the automaticoptimization deceleration curve the function, is composed the velocitymodulation system crawling time by it few, the even level distance isshort, no matter is the double winding electric motor, or electric motor suitable, its highest design speed may reach 4m/s, itsunique computer monitoring software, may choose the serial interfacerealization input/output signal the non- electronic contact control. The frequency changer constitutes elevator system, when the frequencychanger receives the controller to send out shouts the ladderdirection signal, the frequency changer basis hypothesis speed and theacceleration value, the starting motor, after achieved the maximumspeed, the uniform speed moves, when arrives the goal leveldecelerates, the controller sends out shuts off the high velocitysignal, reduces the speed which the frequency changer establishes themaximum speed to reduce to the crawling speed, In decelerates in the movement process, the frequency changer can theautomatic computation decelerate to the even level spot betweendistance, and calculates the optimized curve, thus canaccording tothe optimized curve movement, cause the low speed crawling time toreduce to 0.3s, the frequency changer through adjusts leveling thespeed in the elevator even level process or applies the brake thepitch to adjust leveling the precision. Namely when the elevator stops too early, the frequency changerincreases the low speed value or the reduction applies the brake thepitch value, otherwise reduces the low speed value or increasesapplies the brake the pitch value, when the elevator to leaves evenlevel position 4 - 10cm, has the even level switch automaticseparation low speed signal, the system according to the optimizedcurve realization high accuracy even level, thus achieved the evenlevel accurate is reliable.3. Elevator speed curveElevator movement comfortableness is decided in its movementprocess acceleration a and the acceleration rate of change p size, theoversized acceleration or the acceleration rate of change can createpassenger's ill feeling. At the same time, for guaranteed the elevatorthe operating efficiency, a, the p value not suitable excessively issmall. Can guarantee a, the p best value elevator performance diagramis called the elevator the ideal performance diagram. The elevatormovement ideal curve should be the parabola - straight linecomprehensive velocity curve, namely elevator Canada, reduces theprocess constitutes by the parabola and the straight line. Theelevator assigns the curve is whether ideal, direct influence actualperformance diagram.3.1 velocity curves have the methodUses FX2-64MR PLC, and a consideration input output requestincreased FX-8EYT, FX-16EYR, the FX-8EYR three expansions modules andthe FX2-40AW twisted pair line correspondence adapter, FX2-40AW usesin the system serial communication. Using PLC the expansion functionmodule D/A module realization speed ideal curve output, whenbeforehand the digitized ideal velocity curve stores the PLC register,the procedure movement, through looks up the table way to read in D/A,transforms the simulation quantity after D/A the speed ideal curveoutput.3.2 Acceleration assign the curve the production8 D/A outputs 0 ~ 5V/0 ~ 10V, the corresponding numerical valueis 16 enters system several 00 ~ FF, altogether 255 levels. Ifelevator rise time between 2.5 ~ 3seconds. According to theconservative value computation, in the elevator acceleration processeach time Zha Biao time-gap not suitably surpasses 10ms.As a result of elevator logic control section procedure biggest, butthe PLC movement uses the cyclical scanning mechanism, thus usuallyuses looks up the table method, Zha Biao instruction time-gapexcessively is each time long, cannot satisfiedly assign the curve theprecision request. In the PLC movement process, its CPU with variousequipment between exchange of information, user program execution,signal gathering, control quantity operation and so on output all isdefers to the fixed order to circulate the scanning way to carry on,each circulation all must carry on the inquiry, the judgement and theoperation to all functions. This kind of order and the form capableperson are not the change. The usual scanning cycle, is basic mustcomplete six steps the work, including movement surveillance, andprogramming exchange information, and digital processor exchangeinformation, and communication processor exchange information,execution user program and input output connection service and so on.In a cycle, CPU only carries out to the entire user program. This kindof mechanism has its convenient one side, but timeliness is bad. Theexcessively long scanning time, directly affects the system to thesignal response effect, in under the guarantee control functionpremise, maximum limit reduces CPU the cyclical scanning time is avery complex question. Generally only can short adopt the method fromthe user program execution time. The elevator logic control sectionprocedure scanning time has surpassed 10ms, although has adopted somereduced procedure scanning time means, but still will be unable toscan the time to fall to 10ms below. At the same time, applies thebrake the section curve to use according to is away from theprinciple, each section of distances arrive the response time notsuitably surpasses 10ms. In order to satisfy the system the timelyrequest, in the velocity curve production way, uses the severancemethod, thus effectively has overcome the PLC scanning mechanismlimit.The starting acceleration movement by decides the cycle interruptservice isr to complete. This kind of severance cannot carry on theswitch by the procedure, once establishes, continuously presses thehypothesis time-gap circulation severance,therefore, the startingmovement condition must put in the interrupt service isr, when doesnot satisfy the movement condition, the severance namely returns.3.2 Decelerates applies the brake the curve productionIn order to guarantee applies the brake process completing,must carry on in the master routine applies the brake the condition tojudge and to decelerate a determination. In decelerates before adetermination, the elevator continuously is in the acceleration or thesteady fast movement process. The acceleration process completes bythe fixed cyclical severance, accelerates after the correspondingpattern maximum value, the acceleration procedure movement conditionno longer satisfies, after each time severs, no longer carries out theacceleration procedure, directly returns from the severance. Theelevator corresponds the pattern the maximum value movement,decelerates in this pattern to after, has the high-speed countingseverance, the execution decelerates the service routine. Revises thecounter in this interrupt service isr to suppose the definite valuethe condition, guaranteed the next time will sever the execution. In the PLC internal register, deceleration curve table value from big to small , each time severs all carries out time "theindicator needle to add 1" the operation, then the next severance willlook up the table number is smaller than this severance to look up the table numbers. Thegate area peaceful level area judgement produces by exterior signal,guarantees the moderating process the reliability.4. Elevator control system4.1 Elevators control system characteristicIs relates the elevator movement comfortable feeling target in theelevator performance diagram start section the key link, but thecomfortable feeling with the acceleration direct correlation,according to controls the theory, must cause some quantity accordingto prearrange the rule change to have to carry on the positivegoverning to it, said regarding the elevator control system, mustcause the acceleration to have to use the acceleration feedbackaccording to the ideal curve change, according to electric motormoment of force equation: M - MZ= Delta M=J (dn/dt), obviously theacceleration rate of change had reflected the system dynamic extensionis apart from the change, the control acceleration is apart from DeltaM=M - MZ on the control system dynamic extension. Therefore uses theacceleration in thissection the timing control principle, when thestart ascent portion speed achieved when stable state value 90%,systematically will cut the speed control from the accelerationcontrol, because in the steady fast section, the speed will besmaller for the permanent value control undulation, the accelerationchange will not be big, also will use the speed closed-loop controlto be allowed to cause the stable state speed hold certain precision,will be applies the brake the section precise even level to create thecondition. Uses the PI regulator control in the system speed ascentportion and steady fast Duan Suidu, but two section of PI parameter isdifferent, enhances the system the dynamic response target.Applies the brake the section in the system, namely must to reduce thespeed to carry on the essential control, guarantees the comfortablefeeling, also must strictly controls according to the elevatormovement speed and the distance relations, guarantees the even levelthe precision. In system’s rotational speed reduces to 120r/min in front of, in orderto enable two to obtain the proper attention to both, adopts by theacceleration to the timing control primarily, simultaneously actsaccording to on each as soon as the stopping distance the actualrotational speed and the theory rotational speed deviation revises theacceleration to assign the curve the method. For example in is awayfrom the even level spot some as soon as to be away from L place, thespeed should reduce to Vm/s, but the actual rotational speed is highis V ' m/s, then explained adds the system turns is apart frominsufficiently, after therefore calculates the here to assign reducesspeed value -ag, causes it to add on a negative deviation againepsilon, even if the here reduces the speed given value to revise for- (ag+ epsilon) causes to assign reduces the speed and the true speednegative deviation enlarges, thus enlarged the system to turn thedistance, caused the speed very quickly to fall to the standard value,when electric motor’s rotational speed reduces to 120r/min after, this time thetheater box above the level only had several centimeters, The elevatorrunning rate is very low, for did not prevent phenomenon appearancewhich stops to the even level area, enables the elevator comparativelyquickly to enter the even level area, uses the proportional control inthis section, and uses the time optimization control, guaranteed theelevator accurately promptly enters the even level area, achieves theaccurate reliable even level.4.2 elevators controls constitutionBecause the elevator movement is according to the floor and the theater box calling signal, the travelling schedule signalcarries on the control, but the floor and the theater box call isstochastic, therefore, the systems control uses the stochastic logicalcontrol. Namely in realizes in the elevator basic control requestfoundation by the smooth logic control, according to stochastic inputsignal, as well as elevator corresponding condition at the rightmoment control elevator movement. Moreover, the theater boxposition is determined by the pulse encoder pulse number that, anddelivers PLC the counter to carry on the control. At the same time,each building establishes to approach the switch to use in to examinethe system the floor signal. In order to be advantageous for the observation, is at the floor tothe elevator movement direction as well as the elevator to carry onthe demonstration, uses LED and the photo tube demonstrated, but tothe floor and the theater box calling signal to the indicating lampdemonstrated (on switch has indicating lamp).In order to enhance the elevator the operating efficiency peacefullevel precision, the system requests PLC to be able to theater boxCanada, to decelerate as well as to apply the brake to carry on theeffective control. Realizes according to the theater box physicallocation as well as the exchange velocity modulation system controlalgorithm. For the elevator movement security, the system shouldestablish the reliable fail safe and the corresponding es the PLC realization the elevator control system to constitute byfollowing several main parts.4.2.1 PLC control circuit; PLC receives shouts the ladder from thepanel board and each level to summon the signal, the theater boxand the gate system function signal as well as the well and thefrequency changer condition signal, realizes the elevator collectionafter the procedure judgement and the operation to choose the control.PLC during the output demonstration and supervisory signal, sends outthe movement direction, the start, Canada to the frequencychanger/decelerates moves and applies the brake to stop the ladderequisignal.4.2.2 electric currents, speed double closed loops electric circuit;Frequency changer itself is equipped with the electric currentdetector set, from this constitution electric current closed loop;Through revolves the encoder with the electricalmachinery coaxialjoint, produces a, the b two pulses enters the frequency changer,during confirmation direction, counts the constitution speed closedloop using the pulse.4.2.3 displacements control circuit; The elevator took one kindcarries the person tool, reigns under the potential state of loading,besides request safe reliable, but also requests the movement to besteady, rides comfortably, anchors accurately. Uses the frequencyconversion to modulate velocity Shuanghuan to control may basicallyanswer the purpose, the use existing revolves the encoder toconstitute the speed ring at the same time, moves the proportionthrough the frequency changer PG card output and the electricalmachinery speed and the elevator the pulse number, introduces it PLChigh-speed counting to input the port, through the accumulation pulsenumber, (1) calculates the pulse equivalent after the type, from thisdefinite elevator position. Elevator displacement H=SI In the formula I - accumulation pulse number; S - pulse equivalent; S = plD/(pr) (1) L – Proportion of decelerates ; D - tows the wheel diameter; P - revolves the encoder every time to transfer corresponding thepulse number; R - PG card frequency division ratio.4.2.4 ends stations protection; When in elevator direction detectionline, on the good directional relay, the express train assistancecontact device, the express train movement contact device, the doorlock relay, on the good contact device electricity attracts gathers, mechanical floodgate opens, on elevator line. When the theater box bumps intoforces speed changeing the switch, the PLC internal lock saves the relay toresult in the electricity to attract gathers, timer Tim10, Tim11 startfixed time, it fixed time time length visible end station leveldistance with ladder fast hypothesis. After on forces speed changing theswitch movement, the elevator transfers the slow train movement by theexpress train movement, in the normal condition, the previous line ofeven strata time elevator should stop. If the theater box has notstopped continues the line, when Tim10 supposes the definite value toreduce the zero hour, it the separation, the slow traincontact device and on the good contact device loses the electricity,the elevator stops moving. Bumps into after the arrogant theater boxon forces speed changing the switch, because certain reason elevators have notbeen able to transfer the slow train movement, and the express trainmovement contactdevice has not been able to release, when Tim11supposes the definite value to reduce the zero hour, it N.C. contactthe separation, the express train movement contact device and on thegood contact device loses the electricity, the elevator stops moving.Therefore, no matter is the slow train movement or the express trainmovement, so long as on forces speed changing the switch to send out thesignal, no matter the end stands other protection switches whetheract, can cause the elevator with the aid of Tim10 and Tim11 to stopmoving, thus causes the elevator end station protection to be morereliable.Under when the elevator needs the line, so long as had has chosen theladder instruction, got down the good directional relay to result inelectricity its Chang Kaidian closed, the lock saved the relay toreposition, Tim10 and Tim11 lost the electricity, it N.C. contactclosed for the elevator normal under line has prepared for. The lowerextremity stands the protection principle and the upper extremestation protection similar no longer duplicates.4.2.5 floors count; The floor counts uses relatively counts the way.Before the movement through from the study way, determines thecorresponding floor highly pulse number, corresponds 17 elevatorsseparately to store 16 memories units DM06 ~ DM21. The floor counter(CNT46) is a bidirectional counter, when arrives each level the floorcounts, according to moves the direction to carry on adds 1 or reduces1 to count. In the movement, the high speed counter tiredly estimates the valuereal-time counts the point correspondence pulse number with the floorto carry on the comparison, is equal when sends out the floor to countthe signal, the previous line of Canada 1, the next line reduces 1. Inorder to prevent the counter in counts the pulse high level periodrepetition to count, uses the floor to count on the signal along totrigger the floor counter.4.2.6 is fast speed changing; When the high speed counter value and the fastspeed changing point correspondence pulse number is equal, if the elevator isin the quick operating also this level has chooses the level signal,sends the fast speed changing signal. If the elevator medium speed movement oralthough the quick operating but this not chooses the level signal,then does not send speed changing the signal.4.2.7 areas signals; When high speed counter CNT47 value correspondsin the pulse number scope when the gate area, sends the gate areasignal.4.2.8 pulses signals failure detection; Pulse signal accurategathering and the transmission appears in the system especiallyimportantly, revolves the encoder for the examination and the pulsetransmission circuit breakdown, whether there is has designed thepulse signal and the errors and omissions pulse examination electriccircuit, guarantees the system normal operation through the real-timeexamination. In order to eliminate the pulse to count the accumulativeerror, in base station the establishment reset switch, turns on PLC highspeed counter CNT47 the replacement end.5. Software design characteristic5.1 uses the priority formationPosition and movement direction locates which according to theelevator, in the programming, has used four priorities formations,namely on good priority formation, on line of inferior priorityformation, under good priority formation, next line of inferiorpriority formation. When among them, on good priority formation forelevator upward movement, locates the upward movement calling signalin the elevator which above the position the floor sends out, thearray which should call which the signal cabin correspondence thefloor to have the pulse number depositing register constitutes. Whenprevious line of inferior priority formation for elevator upwardmovement, locates the upward movement calling signal in the elevatorwhich below the position the floor sends out, the formation whichshould call which the signal cabin correspondence the floor to havethe pulse number depositing register constitutes. Control system inelevator movement real-time arrangement four priorities exhibition,has provided the foundation for the realization stochastic logiccontrol.5.2 uses advanced first leaves the formationAccording to elevator movement direction, with to the priorityformation's in non-vanishing unit (has when call this unit is 70units, does not have when call then this unit for zero) (advancedsends in the register formation first to leave formation FIFO), theuse advanced first leaves the read-out instruction SFRDP instruction,sends in the FIFO first unit in data compares the register.5.3 uses the stochastic logical controlWhen the elevator approaches by some movement direction somefloor decelerates the position, distinguished whether this floor doeshave with to the calling signal (on a line of call symbolizedregister, next line of call symbolized when register, has callrequest, corresponding register is l, otherwise is 0), if has, thecorresponding register pulse number and the comparison register willcarry on the comparison, if will be same, then will decelerate in thisfloor stops: If is not same, then sends in this register data comparesthe register, and the original comparison register data preservation,carries out this floor to decelerate stops. After this movementfinished, the data which will preserve reis sent in compares theregister, will realize the stochastic logical control.5.4 uses the software demonstration The system use travelling schedule judgement floor, andtransforms the BCD code output, through hardware connection electriccircuit by LED demonstration.5.5 pair of frequency changers control PLC acts according to the stochastic logical control therequest, may send out to the frequency changer to the movement, thereverse movement, is decelerating as well as applies the brake thesignal, again controls the electrical machinery by the frequencychanger basis certain control rule and the control algorithm. At thesame time, when the system appears the breakdown, PLC to the frequencychanger sends out the signal.6. Concluding remark Uses elevator control system which the MIC340 elevatorspecial-purpose frequency changer constitutes, may realize theintellectualization which the elevator controls, but because theperiod of five days ladder and the elevator in person arrives eachlevel the population is the intelligent elevator is unable todetermine, even if uses the AITP artificial intelligence system, thetransmission transportation passenger flow information also is fuzzy,for solves the elevator this vertical transportation control systemtwo to be big cannot know the factor, will need us to go to theunceasing research and the exploration in the next work.译文:文中分析了电梯的负载特性，阐述了采用梯形加速曲线的电梯理想速度曲线，结合变频器和PLC的性能，论述了电梯控制系统的构成和工作特性。
基于PLC的电梯控制系统的设计英文文献
Design and Practice of an Elevator Control System Based on PLC Xiaoling Yang1, 2, Qunxiong Zhu1, Hong Xu11College of Information Science &Technology,Beijing University of Chemical Technology, Beijing 100029, China2 Automation College of Beijing Union University,Beijing,100101, Chinayxl_lmy@ , zhuqx@,AbstractThis paper describes the development of 2 nine-storey elevators control system for a residential building. The control system adopts PLC as controller, and uses a parallel connection dispatching rule based on "minimum waiting time" to run 2 elevators in parallel mode. The paper gives the basic structure, control principle and realization method of the PLC control system in detail. It also presents the ladder diagram of the key aspects of the system. The system has simple peripheral circuit and the operation result showed that it enhanced the reliability and performance of the elevators.1. IntroductionWith the development of architecture technology, the building is taller and taller and elevators become important vertical transportation vehicles in high-rise buildings. They are responsible to transport passengers, living, working or visiting in the building, comfortable and efficiently to their destinations. So the elevator control system is essential in the smooth and safe operation of each elevator. It tells the elevator in what order to stop at floors, when to open or close the door and if there is a safety-critical issue.The traditional electrical control system of elevators is a relay-controlled system. It has the disadvantages such as complicated circuits, high fault ratio and poor dependability; and greatly affects the elevator’s running quality. Therefore, entrusted by an enterprise, we have improved electrical control system of a relay-controlled elevator in a residential building by using PLC. The result showed that the reformed system is reliable in operation and easy for maintenance.This paper introduces the basic structure, control principle and realization method of the elevator PLC control system in detail.2. System structureThe purpose of the elevator control system is to manage movement of an elevator in response to user’s requests. It is mainly composed of 2 parts:2.1. Electric power driving systemThe electric power driving system includes: the elevator car, the traction motor, door motor, brake mechanism and relevant switch circuits.Here we adopted a new type of LC series AC contactors to replace the old ones, and used PLC’s contacts to substitute the plenty of intermediate relays. The circuits of traction motor are reserved. Thus the original control cabinet’s disadvantages, such as big volume and high noise are overcome efficiently.2.2. Signal control systemThe elevator’s control signals are mostly realized by PLC. The input signals are: operation modes, operation control signals, car-calls, hall-calls, safety/protect signals, door open/close signal and leveling signal, etc. All control functions of the elevator system are realized by PLC program, such as registration, display and elimination of hall-calls or car-calls, position judgment of elevator car, choose layer and direction selection of the elevator, etc. The PLC signal control system diagram of elevator is showed in Figure 1.Figure 1 PLC signal control system diagram2.3. RequirementsThe goal of the development of the control system is to control 2 elevators in a 9-storey residential building.For each elevator, there is a sensor located at every floor. We can use these sensors to locate the current2008 Workshop on Power Electronics and Intelligent Transportation Systemposition of the elevator car. The elevator car door can be opened and closed by a door motor. There are 2 sensors on the door that can inform the control system about the door’s position. There is another sensor on the door can detect objects when the door is closing. The elevator car’s up or down movement is controlled by a traction motor.Every floor, except the first and the top floor, has a pair of direction lamps indicating that the elevator is moving up or down.Every floor, has a seven segment LED to display the current location of the elevator car.The first step for the development of the elevator control is to define the basic requirements. Informally, the elevators behavior is defined as follows.(1) Running with a single elevatorGenerally, an elevator has three operation states: normal mode, fire-protection mode and maintenance mode. The maintenance mode has the highest priority. Only the maintenance mode is canceled can the other operation modes be implemented. The next is fire-protection mode, the elevator must return to the bottom floor or base station immediately when the fire switch acts. The elevator should turn to normal operation mode when the fire switch is reset. Under normal operation mode, the control system’s basic task is to command each elevator to move up or down, to stop or start and to open and close the door. But is has some constraints as follows:Each elevator has a set of 9 buttons on the car control panel, one for each floor. These buttons illuminate when they are pressed and cause the elevator to visit the corresponding floor. The illumination is canceled when the corresponding floor is visited by the elevator.Each floor, except the first and the top floor, has two buttons on the floor control panel, one to request an up- elevator, one to request a down-elevator. These buttons illuminate when they are pressed. The illumination is canceled when an elevator visits the floor, then moves in the desired direction.The buttons on the car control panel or the floor control panel are used to control the elevator’s motion.The elevator cannot pass a floor if a passenger wants to get off there.The elevator cannot stop at a floor unless someone wants to get off there.The elevator cannot change direction until it has served all onboard passengers traveling in the current direction, and a hall call cannot be served by a car going in the reverse direction.If an elevator has no requests, it remains at its current floor with its doors closed.(2) Parallel running with two elevatorsIn this situation, there are two elevators to serve the building simultaneously. It runs at 7am to 9am and 5pm to 7pm every day.When an elevator reaches a level, it will test if the stopis required or not. It will stop at this level when the stop is required.At the same time, to balance the number of stops, theoperation of two elevators will follow a certain dispatching principle.An elevator doesn’t stop at a floor if another car isalready stopping, or has been stopped there.The normal operation of elevators is implemented by cooperation of its electric power driving system and logiccontrol system.3. Software designDue to the random nature of call time, call locationsand the destination of passengers, the elevator controlsystem is a typical real-time, random logic control system.Here we adopted collective selective control method withsiemens PLC S7-200 CPU226 and its extension modules.There are 46 input points and 46 output points in thesystem. The I/O points are showed in Table1 and Table 2.Table 1 Input pointsdescription address 1-8 floor up hall-call I0.0-I0.72-9 floor down hall-call I1.0-I1.71-9 floor car-call I2.0-I2.7, I3.01-9 arrival sensor I3.1-I3.7, I4.0-I4.1door open button I4.2door close button I4.3door close location switch I4.4door open location switch I4.5up leveling sensor I4.6down leveling sensor I4.7fire switch I5.0driver operation switch I5.1touch panel switch of car door I5.2overload I5.3Forced speed changing switch I5.4full load I5.5Table 2 Output pointsdescription address 1-8 floor up hall-call lamp Q0.0-Q0.72-9 floor down hall-call lamp Q1.0-Q1.71-9 floor car-call lamp Q2.0-Q2.7, Q3.0up moving lamp Q3.1down moving lamp Q3.2Seven segment LED display ofelevator’s positionQ3.3-Q3.7Q4.0-4.1door opening Q4.2door closing Q4.3up moving Q4.4down moving Q4.5full load lamp Q4.6high speed operation Q4.7low speed operation Q5.0acceleration of starting Q5.1deceleration of braking Q5.2-Q5.4alarm beeper Q5.5About software designing, we adopt the modularizedmethod to write ladder diagram programs.The information transmission between modules is achieved by intermediate register bit of PLC.The whole program is mainly composed of10 modules:hall-call registration and display module, car-callregistration and display module, the signal combinationmodule,the hall-call cancel module, the elevator-locationdisplay module, the floor selection module, the movingdirection control module, the door open/close module, themaintenance operation module and the dispatchingmodule under parallel running mode.The design of the typical modules is described as follows:3.1. Hall-call registration and displayThere are two kinds of calls in an elevator: hall-calland car-call. When someone presses a button on the floorcontrol panel, the signal will be registered and thecorresponding lamp will illuminate. This is calledhall-call registration.When a passenger presses a button in the elevator car,the signal will be registered and with the correspondinglamp illuminated. This is called car-call registration.Figure2 shows the ladder diagram of up hall-callsregistration and display. The self-lock principle is used toguarantee the calls’ continuous display.Figure 2 up hall-call registration and display3.2. The collective selection of the callsHere the collective selection control rules are used. Asshowed in Figure3, M5.1-M5.7, M6.0 and M6.1 areauxiliary relays in PLC. They denote the stopping requestsignal of 1st to 9th floor respectively. The auxiliary relayM6.2 denotes the elevator driver’s operation signal. Whenthere is a call in a certain floor, the stopping signal ofcorresponding floor will output. When the elevator isoperated by the driver, the hall-calls will not be served.And the elevator cannot pass a floor at which a passengerwishes to alight.3.3. The cancellation of the callsThe program of this module can make the elevatorresponse the hall-calls which have the same direction asthe car’s current direction, and when a hall-call is served,its registration will be canceled. The ladder diagram of uphall-calls’ cancellation is showed in Figure4.Figure 3 The combination of the callsFigure 4 The cancellation of up callsIn Figure4, the auxiliary relay M4.0 is the up movingflag of the elevator. When the current direction of theelevator is up, M4.0’s contacts are closed; on the contrary,when the current direction of the elevator is down, M4.0’scontacts are opened. M0.1 to M0.7 denotes the car-calls’stopping request signal of floor 2 to floor 8 respectively.This program has two functions:(1) Make the elevator response the normal downhall-calls when it is moving down, and when a downhall-call is served, its registration is canceled.(2) When the elevator is moving up, the correspondingfloor’s down hall-call it passing by is not served and theregistration is remained.The cancellation of down hall-calls is reversed with up hall-calls.3.4. Elevator’s directionThe elevator may be moving up or down, depending on the combination of hall-calls and car-calls. The following ladder diagram in Fig.5 illustrates that the elevator will move up.Figure 5 Up moving of the elevatorFigure5 shows that when the calls corresponding floor is higher than the elevator’s current location, the elevator will go up. Here the auxiliary relay M4.0 is used as the up-moving flag. When the elevator is moving up, the up-moving lamp is illuminated, so the M4.0 is connected on. When the elevator arrives the top floor, the up-moving lamp is off and the timer starts. After 0.2s, the M4.0 is disconnected, the up-moving display is off. Here we used M4.0 to replace Q3.1 which can ensure the cancellation’s reliability.3.5. Elevator’s floor-stoppingFigure6 shows the ladder diagram of the elevator’s floor-stopping function.As showed in Figure6, M6.4 is the flag of floor-stopping signal. M6.6 is the floor-stopping signal sent by the driver. M7.0 is the fire signal sent by the fire switch. And M6.7 is the forced speed changing signal. When either of these contacts act, the system should send out the floor-stopping signal.4. Minimum waiting time algorithmIn traffic of elevator systems, there are two types of control task usually. The one is the basic control function to command each elevator to move up or down, to stop or start and to open and close the door. The other is the control of a group of elevators.The main requirements of a group control system in serving both, car and hall calls, should be: to provide even service to every floor in a building; to minimize the time spent by passengers waiting for service; to minimize the time spent by passengers to move from one floor to another; to serve as many passengers as possible in a given time[1].Figure 6 The elevator’s floor-stoppingThere are many dispatching algorithms for elevator’s group control. Such as Nearest-neighbor Algorithm[2], which the elevator always serve the closet request next; Zoning Algorithm[3] which by analyzing the traffic of elevator system with unequal floor and population demand to dispatch the elevator; and Odd-even rule, which an elevator only serves the odd floor and the other only serves the even floor.The Nearest-neighbor Algorithm minimizes the length of the elevator’s empty move to the next request. it usually has very small average waiting times, but individual waiting times can become quite large[2]. The Zoning Algorithm usually used in buildings which has heavy traffic situations, such as the office building at lunch time.Compared to the office building and shopping mall, the traffic flow of residential buildings is relatively lowand even in every floor. Secondly, people usually think of elevators as purely functional objects and the experience of riding an elevator is time waited for most of them. Furthermore, there exist immense problems when attempting to satisfy all requirements.Considering all of the reasons above, we adopted the “minimum waiting time” algorithm to realize the 2 elevators’ parallel running[4].4.1. Evaluation functionThe goal of the “minimum waiting time” algorithm is to predict the each elevator’s response time according to all calls, and select the elevator which has the shortest response time to serve.When there is a call, the system calculates out the function values of each elevator according the evaluation function showed in (1) and (2):J(*)=Min[J(1),J(2),…,J(n)] (1)J(i)=T r(i)+KT d(i)+KT o(i) i=1,2,...,n(2)J(i) is the evaluation index of each elevator; T r(i) denotes the time of the elevator directly moving to the destination corresponding the latest call from its current floor; T o(i) denotes the additional acceleration and deceleration time of a floor-stop of the elevator; T d(i) denotes the average time of the passenger boarding and alighting the elevator; and K is the sum of hall-calls and car-calls. But when a hall-call and a car call corresponds the same floor, the K is only calculated one time.4.2. Calculation of minimum waiting timeIn equation (2), K is a certain value, T o and T d can be obtained by means of statistics. T r = T*L, where T denotes the average time of the elevator passing by one floor; L denotes the desired floors of the elevator from current floor to the hall-call floor.In order to calculate the L value, we defined the 2 elevators are A and B respectively; Y A,Y B denotes the current floor of elevator A and B respectively. H is the corresponding key value when a hall-call button is pressed, and H=floor number of the hall-call.We defined 4 tables for the PLC realization: up hall-call registration table, down hall-call registration table, car-call registration table of A and car-call registration table of B. When a certain call button is pressed, its floor value is recorded in corresponding table.Here we take elevator A as an example. First, define the variable M A, M B and M W. Where M A, M B denotes the extreme value of car-calls with same direction of A or B’s movement respectively.When elevator A is up-moving, set M A is equal to the maximum value in car-call registration table A; when elevator A is down-moving, set M A is equal to the minimum value in car-call registration table A.M W denotes the extreme value of hall-calls with same direction of A’s movement.When elevator A is up-moving and up-hall-call value≥Y A, set M W=0; otherwise, set M W is equal to the minimum value in up-hall-call registration table A. When elevator A is down-moving and up-hall-call value≤Y A, set M W=0; otherwise, set M W is equal to the maximum value in down-hall-call registration table A .Thus, we can determine the L value according to Y A, H, M A and M W. There are 3 situations:(1) When the hall-call’s direction is opposite to elevator A’s movement:L=|Y A-M A|+|M A-H| (3)(2) When the hall-call’s direction is same as elevator A’s movement and it is in the front of elevator A:L=|Y A-H| (4)(3) When the hall-call’s direction is same as the elevator A’s movement and it is in the back of elevator A: L=|Y A-M A |+|M A-M W|+|H-M W| (5)So the i-th floor’s minimum waiting time can be calculated by (6) as follows:Time(i)=TL(i)+KT d(i)+KT o(i) i=1,2,...,n(6)When the calls change during the operation of elevators, the system calculates the minimum waiting time of each elevator. Then it allocates the current call to the elevator which has small value. When the each elevator has the same value, then the current call is prior to elevator A.When an elevator is wrong or not in service, the system can exit the dispatching algorithm and turns to a single elevator running mode.4.3. Algorithm realizationCompared with single elevator running mode, the parallel running mode is mainly different at the processing method about hall-calls. The former uses collective selective control method, and the latter uses dispatch rule combined with collective selective control method.Here the system is to control a 9-storey building, so we choose two Siemens S7-200 PLCs(CPU226) and its Extensive Modules to control the single elevator respectively. And by using PPI Protocol to realize the communication between 2 PLCs.The PPI Protocol adopts master-slave communication mode, so we defined elevator A as the master and elevator B as the slave. By communication program, the 2 PLCs can exchange the massage such as the current position, hall-calls or car-calls and moving direction. Then by using “minimum waiting time” algorithm, the system realizes the optimal operation of 2 elevators.Figure7 shows the ladder program of the car-calls extreme value calculation of elevator A.In Figure7, VB121～VB130 is the register address of elevator A’s car-call corresponding to each floor, Q3.1 isthe up-moving lamp of elevator A , and the car-calls extreme value is saved in VB120.Figure 7 The car-calls extreme value calculationof elevator A5. ConclusionsIn this paper, we have improved an old elevator control system by using PLC, and realized the group control of 2 elevators. The new control system has been operated for 1 year, and its operation scenarios are as follows: (1) Down–PeakThis traffic condition concerns people out of the building in the morning between 7am to 9am. (2) Up–PeakThis condition concerns people entering the building between 5pm to 7pm. (3) OtherIt covers the day from 6:00 to 0:00 except the two situations above. And in this situation, there is only one elevator running.The results are expressed via an average waiting time and maximum waiting time(both given in seconds) are collected in Tables 3 and 4.Table 3Average and maximum waiting time(before reformed)Average Maximum Down–peak 63.20 240.33 Up–peak 52.78 235.26 Other 43.25 215.43Table 4Average and maximum waiting time(reformed)Average Maximum Down–peak 30.12 203.33 Up–peak 27.81 195.20 Other 37.32 186.43Due to the nonparallel running before the reform, so the average waiting time and maximum waiting time of down–peak and the up–peak are very longer than the reformed. The practice results have showed the better performance of the improved control system.References[1] Ricardo Gudwin, Fernando Gomide, Marcio (1998). “AFuzzy Elevator Group Controller With Linear Context Adaptation”. IEEE World Congress on Computational Intelligence . Vol. 12, No. 5, pp.481-486.[2] Philipp Friese, Jorg Rambau (2006). “Online-optimizationof multi-elevator transport systems with reoptimization algorithms based on set-partitioning models”. Discrete Applied Mathematics .No. 154, pp.1908-1931.[3] Zheng Yanjun, Zhang Huiqiao, Ye Qingtai, ZhuChangming. (2001). “The Research on Elevator Dynamic Zoning Algorithm and It's Genetic Evolution”. Computer Engineering and Applications , No. 22, pp.58-61.[4] Xiaodong Zhu, Qingshan Zeng (2006). “A Elevator GroupControl Algorithm for Minimum Waiting Time Based On PLC”. Journal of Hoisting and Conveying Machiner , No. 6, pp.38-40。
PLC控制系统外文翻译
附录Abstract: Programmable controller in the field of industrial control applications, and PLC in the application process, to ensure normal operation should be noted that a series of questions, and give some reasonable suggestions.Key words: PLC Industrial Control Interference Wiring Ground Proposal DescriptionOver the years, programmable logic controller (hereinafter referred to as PLC) from its production to the present, to achieve a connection to the storage logical leap of logic; its function from weak to strong, to achieve a logic control to digital control of progress; its applications from small to large, simple controls to achieve a single device to qualified motion control, process control and distributed control across the various tasks. PLC today in dealing with analog, digital computing, human-machine interface and the network have been a substantial increase in the capacity to become the mainstream of the field of control of industrial control equipment, in all walks of life playing an increasingly important role.ⅡPLC application areasCurrently, PLC has been widely used in domestic and foreign steel, petroleum, chemical, power, building materials, machinery manufacturing, automobile, textile, transportation, environmental and cultural entertainment and other industries, the use of mainly divided into the following categories:1. Binary logic controlReplace traditional relay circuit, logic control, sequential control, can be used to control a single device can also be used for multi-cluster control and automation lines. Such as injection molding machine, printing machine, stapler machine, lathe, grinding machines, packaging lines, plating lines and so on.2. Industrial Process ControlIn the industrial production process, there are some, such as temperature, pressure, flow, level and speed, the amount of continuous change (ie, analog), PLC using the appropriate A / D and D / A converter module, and a variety of control algorithm program to handle analog, complete closed-loop control. PID closed loop control system adjustment is generally used as a conditioning method was more. Process control in metallurgy, chemical industry, heat treatment, boiler control and so forth have a very wide range of applications3. Motion ControlPLC can be used in a circular motion or linear motion control. Generally use a dedicated motion control module, for example a stepper motor or servo motor driven single-axis or multi-axis position control module, used in a variety of machinery, machine tools, robots, elevators and other occasions.4. Data ProcessingPLC with mathematics (including matrix operations, functions, operation, logic operation), data transfer, data conversion, sorting, look-up table, bit manipulation functions, you can complete the data collection, analysis and processing. Dataprocessing is generally used, such as paper making, metallurgy, food industry, some of the major control system5. Communications and networkingPLC communication with the communication between PLC and the PLC and other communications between intelligent devices. Along with the development of factory automation network, the PLC now has communication interface, communication is very convenient.ⅢApplication features of PLC1. 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 failure 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 welcomePLC 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 changed production process possible. This is particularly suitable for many varieties, small batch production situations.(1)Installation and wiring●Power lines, control lines and power lines and PLC I / O lines should be split wiring, isolation transformer and PLC and I / O should be used between the cable connection Shuangjiao. The PLC's IO lines and power lines go separate lines, such as to be in the same groove, the separation of bundled communication lines, DC lines, if conditions allow, the best sub-groove alignment, not only will it have the greatest possible distance and can reduce the noise to a minimum.●PLC should stay away from strong interference sources such as welding, high-power silicon rectifier devices and large power equipment, not with the high-voltage electrical switch installed in the same cabinet. PLC in the cabinet should stay away from power lines (the distance between the two should be more than 200mm). And PLC cabinets installed within the same inductive load, such as large power relay, contactor coil, arc should be parallel RC circuit.●PLC input and output separately from the best alignment, switch and analog should be laid separately. The transmission of analog signals should be shielded cable, one end or both ends of the shield should be grounding resistance should be less than the shielding layer 1 / 10.●AC output line and DC output lines do not use the same cable, the output line should be far from power lines and power lines, to avoid parallel.(2)I / O wiring terminalInput Connection●Input wiring generally not too long. But if the environment interfere with small, small voltage drop, the input terminal can be properly longer.●Input / output lines can not be used with a cable, input / output lines should be separated.●The extent possible, normally open contact form to connect to the input in the establishment of the ladder and relay the same schematic, easy to read。
PLC控制系统外文文献翻译、中英文翻译、外文翻译
PLC控制系统一、PLC概述可编程控制器是60年代末在美国首先出现的，当时叫可编程逻辑控制器PLC （Programmable Logic Controller），目的是用来取代继电器。
以执行逻辑判断、计时、计数等顺序控制功能。
提出PLC概念的是美国通用汽车公司。
PLC的基本设计思想是把计算机功能完善、灵活、通用等优点和继电器控制系统的简单易懂、操作方便、价格便宜等优点结合起来，控制器的硬件是标准的、通用的。
根据实际应用对象，将控制内容编成软件写入控制器的用户程序存储器内,使控制器和被控对象连接方便。
70年代中期以后，PLC已广泛地使用微处理器作为中央处理器，输入输出模块和外围电路也都采用了中、大规模甚至超大规模的集成电路，这时的PLC已不再是仅有逻辑(Logic)判断功能，还同时具有数据处理、PID调节和数据通信功能。
国际电工委员会(IEC)颁布的可编程控制器标准草案中对可编程控制器作了如下的定义：可编程控制器是一种数字运算操作的电子系统，专为在工业环境下应用而设计。
它采用了可编程序的存储器，用来在其内部存储执行逻辑运算，顺序控制、定时、计数和算术运算等操作的指令，并通过数字式和模拟式的输入和输出，控制各种类型的机械或生产过程。
可编程控制器及其有关外围设备，易于与工业控制系统联成一个整体，易于扩充其功能的设计。
可编程控制器对用户来说，是一种无触点设备，改变程序即可改变生产工艺。
目前，可编程控制器已成为工厂自动化的强有力工具，得到了广泛的普及推广应用。
可编程控制器是面向用户的专用工业控制计算机，具有许多明显的特点。
①可靠性高，抗干扰能力强；②编程直观、简单；③适应性好；④功能完善，接口功能强二、PLC的历史1968年，Richard E. Morley创造出了新一代工业控制装置可编程逻辑控制器(PLC),现在，PLC已经被广泛应用于工业领域，包括机械制造也、运输系统、化学过程设备、等许多其他领域。
PLC控制电梯外文翻译
Variable Frequency Speed-regulation System of ElevatorUsing PLC TechnologyAbstract-In this paper, the system of variable frequency speed-regulation based on PLC was proposed. Firstly, the overall structure of control system was determined. Inverter and programmable logic controller were chosen to complete variable frequency speed-regulation. Secondly, parameters of inverter were set by develop system hardware. PLC drive selection and 110 points distribution were completed; rotary encoder was connected with PLC interface. Finally, the software flow charts and ladder programs were designed by analysis of elevator system on the basis of software design methods.Keywords-variable frequency speed-regulation; program; logic controller; elevator control systemI. INTRODUCTIONHuman power was used as simple lifting equipment before Christ in china, until now hand-gin still was used as lifting device for extraction wells water in some rural of northern areas. So China is one of the earliest countries of the world in the aspect of elevator prototype [1]. In 1854, Elisa Graves Otis from Americans had shown his invention at the World Expo to the world in the Crystal Palace from New York, which was the first safety elevator in history [2]. Since then, elevator has been widely used in the world.In modem life and economic activity, elevator has become a sign of the city. Elevator has been used as essential vertical transportation equipment, especially in high-rise building. The control systems of relays were used in the conventional elevator, whose control functions and signal processing were realized by hardware. Most of electrical components were common control electrical appliances [3]. Such elevator has been produced with mature technology in the past years, which has been formed series of products. With the rapid development of social economy and improvement of life quality, the shortcomings from traditional elevator controlled by original DC converter and relay had been more and more obvious and exposed many problems: (I) the traditional elevator control system have high failure rate that were mainly due to numerous contacts, complexity of wiring circuit. In addition, electrical contacts were easy to bum out, which could result in poor contact. (2) Electrical controller and hardware wiring based on common method were difficult to achieve a more complex control function, that is, why the functions of system control were difficult to increase. (3)Electromagnetic agencies and contact action were so slow, mechanical and electromagnetic have large inertia. Therefore, the control precision of system was difficult to rise. (4)The traditional elevator control systems have some shortcomings, such as large structure, high energy consumption, serious mechanical noise and so on. (5) Due to line complex and high failure rate of control system, large maintenance workload and high cost were required. It was shown that we should execute a comprehensive transformation to the traditional elevator control system.II. INVERTER PARAMETERS DESIGNElevators were used as vertical transport tool, which belong to potential energy load and require frequent start and stop [4]. With the change of the passenger capacities, up or down transformation, the motor has minimum load. When elevator was run in no load up-going or heavy load down-going, motor was used in the state of power generation. Similarly, the motor has maximum load when elevator was run in heavy load up-going or no load down-going, motor wasused in the state of power. Therefore, the motor was required to run in the four quadrants of axis [5]. The change of motor work states were realized by contactors in the traction motor of traditional elevator. Speed control of motor was completed by series resistance or series reactance in the stator circuit of two-speed asynchronous motor, which can not satisfy the comfort of passengers. Traditional relay control modes were replaced by PLC control method, which could gradually transited from DC speed adjusting system to AC variable frequency speed adjusting system in the modes of motor drag [6].A. Inverter Type SelectInverter is the voltage frequency converter, which could convert AC with fixed requency to adjustable frequency voltage AC to supply the motor operation. Considered control requirements and reliability factors from elevator, ANCHUAN VS-616G5 digital inverter was used in this design. The PG card and rotary encoders must be equipped with VS-616G5 inverter in the speed control system of elevator in order to supply motor speed and feedback [7]. Rotary encoder was connected with the coaxial of motor to detect the motor speed. A, B were represented as two phase pulse outputs from rotary encoder. When A phase pulse was ahead of B phase pulse 90' , the electric motor was operated in the state of forward rotation. Similar, when the A phase pulse was lag of the B phase pulse 90' , the electric motor was operated in the state of reverse rotation. According to phase sequence of A, B pulse, the direction of motor rotation could be determined by rotary encoder. Motor speed could also be measured by frequency or period of A, B pulse. Feedback signals were sent into VS-61605 through PO card to operation regulation [8]. The pulse waveform of A, B phases were shown in figure I.B. Calculation of Inverter Capacity and Braking ResistorWe had supposed that elevator motor power of traction machine was defined as P1,operate speed of the elevator was V1, lift weight was W1 , lift truck was W2,additional weight W3, acceleration of gravity was g , Power of inverter was P. With the maximum load, the traction power P2 in the process of elevator rise [9].Which, was friction; δ could be negligible;inverter power P should be close to electrical power P1.the safety surplus capacity must be considered relative to traction power P2. Therefore, P=1.5P2, we could known from experience value,Therefore, the inverter capacity was selected about 15KW.As elevator was potential energy load, variable frequency speed regulation system should have a brake function since elevator could generate renewable energy during the process of operation. When VS-61605 was used in the system of speed control, the braking resistors must also be configured. When the elevator was worked in the deceleration, the electric motor was run in the power generation state and feedback power to the inverter. DC part voltage from AC-DC-AC inverter could increase when sync speed dropped [10].The role of braking resistor was feedback power and suppresses DC voltage. Renewable energy were consumed in the braking resistor through the brake unit by use of the energy consumption braking mode, which has lower cost and good results.The value of energy consumption braking resistor R2 should be made the value of the braking current I z does not exceed the half of the inverter current.Which, U0 was defined as DC bus voltage of inverter in the rated state, R2＞30Ω.Because the work of braking resistor was not continuous long-term work, the power could be significantly less than the power consumed.III. HARDWARE DESIGNThe hardware of elevator control system was composed by Car Lateral Control Panel, Elevator Landing Door Signal, Inverter, and Adjustable Speed Drives. The structure chart of control system was shown in figure 2.The function of adjustable speed was completed by inverter and logic control section wascompleted by the PLC controller. The logic relatives of various signals were responsible for PLC to send on/off control signals to inverter. At the same time, the working status from inverter was transported to PLC .the bilateral contact relationships were established. The speed loop and position loop were established by established to complete speed test and feedback by equip with PO card and Rotary Encoder, which could be connected with Motor coaxial connector. In addition, the system also must be configured with the brake resistor [11]. When the elevator deceleration, DC voltage hypertension must be suppressed due to motor working in the state of renewable generation power, which will back power to inverter.A. Motor Drive Control SystemSimilar as other elevator control systems, control system based on PLC was also mainly composed of two parts, that is, signal control system and motor drive control system. The basic structure of PLC elevator control system was shown in figure 3. The main hardware had been included by PLC controller, CPU memory, machinery, car lateral control panel, call elevator plate outside of hall, layer device, gate machine, adjustable speed drives, main motor drive system and so on.According to the position detection method of Car Lateral from rotary encoder, a high-speed counter was required in the programmable logic controller. FX2N PLC from Mitsubishi Company made in Japan was chosen. The control instructions from elevator were realized by PLC software. The management and control functions of command signals were completed by PLC controller, such as start, acceleration/deceleration and stop of elevator traction motor and open/close door motor, operate direction, floor display, landing call, car lateral internal operation command, security and so on.B. Signal Control SystemInput control signal to the PLC have included that run mode selection, operation control signal, Car Lateral internal instructions, elevator plate calls, signal security information, rotary encoders, optical pulse, on/off door controller and limit level signals, door area and flat layer signals. The control system of six level elevators was used as an example in this paper. According to the need of control switch, about 48 input points and 30 output points need to be control. FX2N a 128MR model of PLC was chosen when we have considered about 10% to 15% surplus capacity of control points [12]. The signal control system of elevator was shown in figure 4.IV. SOFTW ARE PROCESSA. Main ProgramControl system proposed from this paper was a system of collective selective control. The modular programming methods were used to classify various properties of output signal, medium registers were used to connect different modules to transmit information. System software could be divided into some follow modules, that is, floor detection circuit module, seven segment LED display floor circuit module, elevator direction selection circuit module, deceleration point signal generator circuit modules, on/off door of elevator car lateral circuit module, button memory lights display circuit module and the other modules. In the floor detection circuit module, floor encoding were read into and memory signals were saved in the corresponding registers until the floor changes. LED display was controlled in the seven segment display circuit module. Elevator up or down judgments in response to call the elevator were completed in the elevator direction selection circuit module. Main program flow chart of system software was shown in figure 5.B. Floor Display ProgramElevator will running in the deceleration state when current floor consistent with target detection floor. During the process of operation, elevator will go through many floor detection points. Deceleration notification will be emitted only when elevator reach the detect point of goal floor. After receive deceleration notification signal, elevator had started slow down. The flow chart of floor display program was shown in figure 6.PLC output ports were directly connected with seven- segment LED, which need not external hardware decoder. Seven-segment LED was compiled by PLC software to directly display floor number. The seven-segment LED digital tube was commonly used, which is a digital distribution in a plane by a number of light-emitting diodes or liquid crystal segments to form a variety of digital code. Seven-segment LED digital tube was distributed in a plane. Digital codes of floor were composed by some light-emitting diodes or liquid crystal segments. Seven segment LEDdisplay circuit was shown as figure 7.In the display circuit of seven-segment code, input pin a, b, c, d, e, f, g of LED wereconnected with 24V power supply, then the corresponding section will be lighted, the control terminals Y10 -Y16 of programmable logic controller will be closed or open, which could control on or off state to appear the corresponding value in the appropriate section of LED. Digital display of values and correspond pins were shown in table I. Among them, output state I was defined as bright field of the seven segments LED; output state 0 was defined as dark field of the seven segments LED.V . CONCLUDESVariable frequency speed-regulation and programmable logic controller technology were used to transform old elevator. The reliability of the elevator was improved through reasonable equipment selection, parameter setting and software design. The elevators after transformation have obvious advantages such as structure compact, low noise, high efficiency, simplymaintenance and low failure rate. The elevator based on variable frequency speed- regulation and programmable logic controller technology have improve passenger comfort and reliable.Maintenance costs and power consumption of motor were reduced significantly. But there are still many areas for improvement: (I) Changed with fluctuate in traffic; the functions of select direction of elevator were optimized to achieve the purpose of efficient transport of passengers. (2)Emergency approaches will be increased in the fault conditions. These problems will to be perfect in the future.ACKNOWLEDGMENTFirst and foremost, I would like to show my deepest gratitude to my supervisor, Dr. Zhang. a respectable, responsible and resourceful scholar, who has provided me with valuable guidance in every stage of the writing of this thesis. I shall extend my thanks to Mr. Wang for all his kindness and help. I would also like to thank all my teachers who have helped me to develop thefundamental and essential academic competence. My sincere appreciation also goes to all my friends for their encouragement and support.采用PLC 技术的电梯变频调速系统摘要：本文提出了基于PLC 测定的变频调速调节系统。
PLC及变频器技术中英文对照外文翻译文献
(文档含英文原文和中文翻译)中英文资料对照外文翻译PLC and inverter technology trends1. The development trend of the programmable controller“PLC is one kind specially for the digital operation operation electronic installation which applies under the industry environment designs. It uses may the coding memory, uses for in its internal memory operation and so on actuating logic operation, sequence operation, time, counting and arithmetic operation instructions, and can through digital or the simulation-like input and the output, controls each type the machinery or the production process. PLC and the related auxiliary equipment should according to form a whole easy with the industrial control system, easy to expand its function the principle to design.”In the 21st century, PLC will have a bigger development. Technologically speaking, computer technology's new achievement more will apply in the programmable controller's design and the manufacture, will have the operating speed to be quicker, the storage capacity to be bigger, an intelligent stronger variety to appear; Looked from the product scale that further develops to subminiature and the ultra-large direction; Looked from the product overcoatability that the product variety will be richer, the specification to be more complete, the perfect man-machine contact surface, the complete communication facility will adapt eachindustrial control situation demand well; Looked from the market that various countries will produce the multi-variety product the situation to break respectively along with the international competition aggravating, will present the minority several brand monopoly international market the aspect, will present the international general programming language; Looking from the network state of play, the programmable controller and other industrial control computer network constitution large-scale control system is the programmable controller technology development direction. Present computer collection and distribution control system DCS (Distributed Control System) had the massive programmable controller application. Is following computer network's development, the programmable controller takes the automation directed net and the international universal network important component, outside industry and industry numerous domain display more and more major function.2. Inverter technology development trendsInverter into the practical phase of more than 1 / 4 century during this period, the frequency converter technology as the basis of power electronics technology and microelectronics technology manager of a leap in the development, as the new power electronic devices and high-performance microprocessor The application of control technologyand the development of increasingly high cost performance of the inverter, more and more small size, but manufacturers are still in constant frequency converter to achieve the further miniaturization and doing new efforts. From a technical point of view, with the frequency converter to further expand the market of the future, with the converter and inverter technology will be on the development of technologies in the following areas further development:(1) large capacity and small size;(2) high-performance and multi-function;(3) enhance the ease-of-use;(4) increase in life expectancy and reliability;(5) of pollution-free.Large capacity and small size of the power semiconductor devices will be with the development of continuous development. In recent years, driven by a voltage power semiconductor devices IGBT (Isolated Gate Bipolar Transistor, isolation gate bipolar transistors) has developed very rapidly and quickly into the traditional use of BJT (bipolar power transistor) and power MOSFET (FET) The various fields. In addition, the IGBT switching device for the IPM (Intelligent Power Module, IPM) and Monolithic Power IC chip will power switching devices and driving circuit,such as the protection of integrated circuits in the same package, with high performance and reliability The merits, with their high current and high pressure of the development of small and medium-sized converter will certainly be more widely used.With micro-electronics technology and semiconductor technology development, for Inverter CPU and semiconductor devices and a variety of sensors of getting higher and higher. With the frequency converter technology and the development of the growing maturity of the exchange governor, modern control theory are constantly new applications. These have further improved the performance of inverter provided the conditions. In addition, with the frequency converter to further promote the use and support are also constantly made new demands, the frequency converter manufacturers to continuously improve the performance and frequency converter functions in Inverter new efforts to meet user And the need for the fierce competition in the market in an invincible position.With the frequency converter market continues to expand, how to further enhance the ease-of-use inverter, so that the technical staff and even ordinary non-technical staff can quickly master the use of frequency converter technology has become manufacturers must consider the issue. Because only easy-to-use products can continue to acquire new customersand further expand the market, so the future of the new converter will be more easy to operate.With the development of semiconductor technology and the development of power electronics technology, the frequency converter used in the various components of the life and reliability are constantly improving, they will make their own life and the frequency converter to further increase reliability.In recent years, people have attached great importance to environmental issues, and thus a "green products" name. Therefore, the inverter, must also consider its impact on the surrounding environment.Promote the use of the frequency converter in the early stages of the noise problem was once a big problem. With the low-noise converter IGBT the emergence of this issue has basically been resolved. However, with the noise problem to solve, people's looks and a converter to the surrounding environment and the impact of other continuously explore new solutions. For example, the use of a diode-voltage converter and PWM inverter circuit converter, the frequency converter itself the high harmonics will bring supply voltage and current distortion, and at the same power to affect the other equipment. However, through the use of the frequency converter Rectifier circuit PWM, we can basically solve the problem. Althoughbecause of price and control technology and other aspects of the reasons for the current PWM converter has not been promoting the inverter, but, with the frequency converter technology development and the people of the importance of environmental issues.PLC及变频器技术的发展趋势1．可编程控制器的发展趋势可编程控制器是一种数字运算操作的电子系统，专为在工业环境下应用而设计。
基于PLC的电梯控制系统设计中英文翻译
Elevator System Based on PLCComposed by the order of relay control system is a realization of the first elevator control method. However, to enter the nineties, with the development of science and technology and the widespread application of computer technology, the safety of elevators, reliability of the increasingly high demand on the relay control weaknesses are becoming evident.Elevator control system relays the failure rate high, greatly reduces the reliability and safety of elevators, and escalators stopped often to take with the staff about the inconvenience and fear. And the event rather than taking the lift or squat at the end of the lift will not only cause damage to mechanical components, but also personal accident may occur.Programmable Logic Controller (PLC) is the first order logiccontrol in accordance with the needs of developed specifically for industrial environment applications to operate the electronic digital computing device. Given its advantages, at present, the relay control the lift has been gradually replaced by PLC control. At the same time, AC variable frequency motor speed control technology, the way the lift drag speed has been a gradual transition form DC to AC frequency converter. Thus, PLC control technology increases VVVF Elevator modern technology has become a hot industry.1. PLC elevator control advantages:(1) Used in elevator control PLC, with so ware for automaticcontrol of lift operation, reliability greatly increased.(2) Layer was removed and majority of the relay, the control system structure is simple, simplify the external circuit.(3) PLC can be a variety of complex control system, easy to add or change control functions.(4) PLC can be automated fault detection and alarm display to improve the operation of security and ease of maintenance.(5) For the group control the allocation and management, and improve the efficiency of elevator operation.(6)Do not need to change the control scheme changes when the hardware connection.2. VVVF elevator control characteristics.With the power electronics, microelectronics and computer technology to control the rapid development of technology, communication technology VVVF also a very rapid rate. AC variable frequency motor speed control technology is the power to improve the process in order to improve product quality and improving the environment and promoting technological progress as a primary means. Frequency of its excellent performance and the speed brake from a smooth performance, high efficiency, high power factor and power-saving of a broad scope of application and many other advantages of being at home and abroad recognized as the most promising approach speed.Exchange characteristics of VVVF Elevator:(1) low energy consumption.(2) low load circuit, the re emergency power supply device of small.In the acceleration stage, the required start-up current of lessthan 2.5 times the rated current. Peak starting current and time is short. Since the starting current is drastically reduced, so power consumption and power supply cable diameter can be reduced a lot. Required for emergency power supply devices are also relatively small size.(3) high reliability and long service life.(4) good comfort.Elevator operation is best to follow the speed curve of a given operation. Their characteristics can be adapted to human feelings, andto ensure that noise operation, smooth brake Ping layer and high precision.(5) stable noise-free.(6) In the car, the engine room and adjacent areas to ensure that noise. Because their systems use a high clock frequency. Always producea true sine wave power supply current yet. Motor torque ripple does not appear. Therefore, to eliminate vibration and noise.3. Elevator control technology.The so-called elevator control technology refers to the elevatordrive system and electrical control system of automatic control. 70 asthe 20th century in China’s elevator were marked by the exchange oftwo-speed elevator. Its speed is used to change the elevator traction motor of the very few, two or mute-level approach to the number of windings, very few of them as high-speed winding of the winding, a very few number of windings as thelow-speed winding. Windings for high-speed elevator-speed start-up and running, low-speed windings for braking and the maintenance of elevators.The early 80s, VVVF inverter controlled variable lift system available. It uses AC motor drivers, are able to reach the level of DC motor, control the speed of the current has reached 6 m/sec. Its small size, light weight, high efficiency, energy saving, inc1uding the past almost all the advantages of the lift. Is the latest elevator drive systemOperation in vertical lift, there is also the starting point of the terminus station. For more than three-story elevator buildings, the starting point of the terminal stations and stops between the had not, the starting point for these stations at the first floor of the terminal located at the highest floor. Starting point in the first floor of the station known as base stations, known as the starting point at both ends of the terminal stations and stations at both ends of intermediate stops between stations.Outside the station has a call box, box set are used by staff for elevator call button or touch the call button, the general ends of the lift stations in the call box on the Settings button or touch of a button. 1iddle layer of the station set up the call box button or touchbutton 2. No drivers for the control of elevators, at various stations are set up calls me on a button or touch button. Elevator car and the internal settings (except for debris elevator) to manipulate me. Control box switch on the handle or set up stations and the corresponding layer of buttons or touch-button control box on the touch-control button or command button or touch the city button. Outside the command button or touch-button issue as the signal outside the command signal, within the command button or touch-button issue within the signal as a command signal. 80 In the mid-20th century, the touch button has been replaced by micro-button.As the elevator call box outside the base station, in addition to set up a call button or touch button, but a1so set a key switch in order to work the elevator clearance. Drivers or management staff to open the elevator to the base station can wriggle through a dedicated key to the key switch. Close the elevator in place to autocratically cut off the elevator control power supply or power supply.4. PLC Control Elevator Design.With the continuous development of urban construction, the increasing high-rise buildings, elevators and life in the national economy has a broad application. Elevator high-rise buildings as a means of transport in the vertical run of daily life have beeninextricably linked with people. In fact the lift is based on external call control signals, as well as the laws of their own, such as running, and the cal1 is random, the lift is actually a man-machine interactive control system, simple to use control or logic control order can not meet the control requirement, and therefore, elevator controlsystem uses a random control logic. Elevator control is current1y generally used in two ways, first, the use of computer as a signal control unit, the completion of the lift signal acquisition, operation and function of the se, to achieve the lift and set the autocratic scheduling function to run the election, drag the control from inverter to complete; the second control mode with programmable logic controller (PLC) to replace the computer control signal sets the election. From the control and performance, these two types of methods and there is no significant difference. Most of the domestic manufacturers to choose the second approach, because the smaller scale of production there design and manufacture of high cost of computer control devices; and PLC high reliabi1ity, convenient and flexible program design, anti-interference ability, stable and reliable operation of the characteristics of Therefore, the elevator control system is now widely used to realize programmable control.5. Lift control system.Lift control system is used to manipulate each control process by managing such commands as running direction, car call, landing call, load signal, landing indication, safety protection.Lifts in different applications have different load, speed anddrive / control modes. Lifts in same application may also have different control mode. Whatever control mode is adopted, the objective is the same, to be specific, according to car call and landing call, lift control system will execute automatic logic judgment to determine which lift will receive signal, which direction lift will run towards andcomplete programmed control objective through electrical automatic system based on command.Types of lift control system.Control system development chronicle indicates that there has appeared many control modes, such as such as relay control, PLC, single computer control, multiple-computer control. Prevailing in different era, these control modes are still employed in lifts now due to massive integrated circuit and computer technology development.PLC control system.As abbreviation of programmable logic controller, PLC is an electronic system featuring digital computation. It adopts programmable EPROM to execute logic computation, order control, timing, number counting, arithmetic computation, besides, it can input and output through digital or analogy modes.The mechanism of PLC control is as follows: input of PLC includes such command signals, as power key to home landing, car call, landing call, various safety switches, position signal, while output of PLC includes contactor, relay, indicators of car / landings and communication unitary, indicators inside car and switch, position signal, are input to PC, while other executing com.Programming principle is determined by lift control mode. Programming can either be made according to relay logic control circuit or individually in different phases according to lift control functions after completely separating from relay control circuit. Based on theready made control circuit, the former is simple and easy to master, while the latter involves less programs by integrating programs of small function.Used in lift control system, PLC has such advantages, as high reliability, stability, easy programming, user-friendliness, convenient maintenance & inspection.Nowadays, there is a wide range and series of programmable logic controllers. Input / output points range from 30 to 8000 or above, so as to meet lift control requirements with different landing number.。
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(文档含英文原文和中文翻译)中英文对照外文翻译文献Application of PLC in the Elevator Control System ofIntelligence BuildingAbstract: The paper mainly discusses one subsystem of intelligence building system: the elevator control system. The PLC strong ability in interference and so on makes the elevator industry one after another to apply the PLC to the elevator control system in order to replace the relay being used in traditional elevator control system. The Application of PLC in the Elevator control system reduces the breakdown rate and efficiently improves the operating reliability of the elevator with safety .The structureof system is also simple and tightly packed.The working principle of the elevator control system is: The spot control information is send into the ＰＬＣfrom the customer input devices firstly, then the PLC control cabinet is required to send out the control signal to drive the equipments according to the system demands. The elevator can then proceed the homologous action according to the control request .The paper selectsＯＭＲＯＮcompany’s Ｃ200HE series PLC, introducing parts of signal hookup of the elevator control system and explaining the function of the control cabinet. Lastly the automation programming is introduced. Simulated experiments enunciates that the design method is viable. It can make the personnel of the industry management center to long-distance monitor and control the elevator in control center, to connect the elevator control system with intelligence building industry management system by Ethernet or special-purpose network such as Lon Works.The elevator working state can also be timely watched.These not only can realize scientific centralized management of the elevator, but also can lower the elevator maintenance cost etc. It is one of the developing direction of intelligence building elevator control system.Keywords: PLC; intelligence building; elevator control system; working principle; program designⅠ. IntroductionIn 1980s The first intelligence mansion had been completed in America, then intelligence building has been abroadly taken attentions by the whole world.The concept of intelligence building has been put different meanings along with the development of society. The early stage intelligence building had been thought that it is equal to the intelligent mansion, but now the intelligence building not only includes the intelligence mansions but also involves intelligence residential districts. This paper mainly discusses one subsystem of intelligence building system: the elevator control system.In intelligence residential districts the enterprise’s information managing system mainly takes charge of the things which related to the daily life, for examplesupervising the district equipments, managing vehicles, disposing critical situations and so on.The elevator supervising and control system is also necessary to the intelligence residential districts.How to make people feel safe ,stable and comfortable and how to save energy resources and protect environments and so on are the basic requirements to the elevator control system.PLC is a common industry control device.It is a special industry control computer which has the perfect function and simple frame. The PLC strong ability in interference and so on makes the elevator industry one after another to apply the PLC to the elevator control system, in order to replace the relay being used in traditional elevator control system. The Application of PLC in the elevator control system reduces the breakdown rate and efficiently improves the operating reliability of the elevator with safety. This paper mainly discusses the elevator control system’s working principles, the system’s software and hardware realization methods and so on.Ⅱ. The Working Principle of Elevator Control System In Fig. 1 the Hardware Structure Graph of Elevator Control System is presented.Fig. 1 The Hardware Structure Graph of Elevator Control SystemThe Working Principles of Elevator Control System are stated as follows: The spot control information is send into the PLC from the customer input devices firstly, then the PLC control cabinet is required to send out the control signal to drive the equipments according to the system demands. The elevator can then perform thehomologous action according to the control request. There are velocity feedback devices in system, which adopt measure velocity generators to provide the elevator velocities and generally are installed in the tail of tow motors .So this is a feedback control system, which can improve the system’s control precision.Ⅲ. The Hardware Configuration of Control System It is not necessary to do interface circuit in the elevator’s PLC control system.What we should do is to send the signals to PLC digital input terminals.The signals include inside and outside calling signals ,floor location inspecting signals , limiting location signals ,opening and shutdown the elevator door signals etc. The DC power which is provided to PLC can be used as indicator light power. The PLC output points can be directly used to control transduce rs for the purpose of electrical motor’s positive turn and reverse ,stop and control each segment velocity and so on .ＯＭＲＯＮcompany’s Ｃ200HE series PLC has been selected as major control configuration according to the input/output points and the length of user’s program. On the other hand we also consider that the system’s function can be expanded in the future .Ｃ200HE series PLC ,whose perfect function and strong reliability, can meet these demands at present.Moreover, input and output devices are needed in elevator control system, besides the PLC, system’s major control device.Part of signal hookups of the elevator electric control system is shown in Fig.2.The control cabinet is the control center, from which we can send out various control commands. The control cabinet often was installed in the elevator room .The electric devices and signal systems, for example the contactors, relays, capacitances, resistors, rectifiers and transformers etc., are centralized in the control cabinet. The Power of the control cabinet was imported from the chief power of the elevator room. This power was also introduced into control panel by soft cables and was linked with each control buttons. The power lines which was derived from control cabinet was delivered to tow electric motors. Others control lines and signal lines were separately sent to each floor junctionⅣ. Program designThe design includes two parts: hardware and software.The hardware design is the base of software. Considering that the control demands are relatively complex, we design the programs separately according to the control function. Furthermore, we follow the principle as follows: When the elevator is ascending, the ascending demands are prior to other demands; When the elevator is descending, the descending demands are prior to other demands. The Sequential Function Chart (SFC) is adopted during the boxes to form elevator’s executive circuitry design. It is a method specially used in industrial sequential control. The SFC method can describe the system’s working procedure in great detail. For example there is a three layers intelligence building. A subprogram, the calling from the third floor as elevator in the first floor, is shown in Fig. 3 with SFC.When all SFC are drawn and I/O address lists are presented, we can convert the SFC to Ladder Diagram (LD).Considering the strict demands for time and for locked each other ,we introduce working bits to remember working steps. We should write out the working bits control program, which can link together each step and make the previous step as the next step restriction condition. Thus the actual outputs are the logic combination of these working steps.Ⅴ. ConclusionThe system program has been debugged completely at present. Simulated experiment enunciates that the design method is viable. Application of PLC in the elevator control system is an effective method. It can make the personnel of the industry management center to long-distance monitor and control the elevator in control center, to connect the elevator control system with intelligence building industry management system by Ethernet or special-purpose network such as Lon Works. The elevator working state can also be timely watched. These not only can realize scientific centralized management of the elevator, but also can lower the elevator maintenance costs etc. It is one of the developing direction of intelligence building elevator control system.References[1]Liang jianqi , Duan zhengang,and He wei .CommunicationImplementation of PLC-Based Elevator Remote Monitoring System (in Chinese)[J] Journal of Beijing Technology and Business University 2003,21(2):18-21[2]Ma Hongqian ,Zhang Xin .Application of PLC in Higher Building Elevator Control System (in Chinese)[J]Journal of Liaoning Higher V ocational Technical Institute 2002,4(5): 86-88.[3]Cui Guangyuan. The Application of PLC to Elevator Control. (in Chinese)[J]Journal of Dongbei Electrical Power Technology 2003,(7): 50-52.Author BiographiesThe first author is currently working as a teacher in Taiyuan University of Technology. Her current research interests include signal processing, intelligence control etc.The second author is currently working as a teacher in Taiyuan University of science and Technology. Her current research interests include telecommunication, intelligence control etc.附录B 外文翻译PLC在智能建筑电梯控制系统中的应用摘要：本文主要讨论了智能建筑系统的一个子系统：电梯控制系统。