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1外文文献•1.INTRODUCTION•ElectricDriveTechnologyDevelopment1.1CurrentSituation30Overtheyears,theDCmotordrivehasundergonesignificantchanges.Firstofall,replacingarectifier,thyristorrectifierdevicetoreplacetheconventionallong-standinggroupofDCmotorsandgeneratorsofmercuryrectifierDCelectricdrivedevicetocompleteabigleapforward.Atthesametime,controlcircuithasachievedahighlevelofintegrationandminiaturization,highreliabilityandlowcost.Morethantechnology,sothatDCSpeedControlSystemincreaseperformance,expandingthescopeofapplication.DCdrivetechnologydevelopmenttomature,andperfect,serialization,standardization,inthereversiblePWM,high-precisionfieldofelectricaltransmissionisstillhardtoreplace.•1.2.ComputercontrolandstatusofthedevelopmentofmotorRelativelysimplecomputercontrolofthemotor,aslongastheuseofmicrocomputercontrolrelayorelectronicswitchingelementssothatthecircuitopenoroffit.Inavarietyofmachinetoolequipmentandproductionlines,thenowcommonlyusedwiththeprogrammablecomputercontroller,inaccordancewiththelawsofcertaintypesofmotorcontrolaction.Forthecomplexmotorcontrol,thenusecomputercontrolmotorvoltage,current,torque,speed,angle,etc.,sothatmotorinaccordancewiththeinstructionsgivenaccuratework.Throughcomputercontrol,motorperformancecouldgreatlyimprove.•2.Speedandcurrentdualclosed-loopspeedcontrolsystemofthetworegulatorcascadeconnectionfortheouterspeedfeedbackloop,currentloopfortheinnerring.Thespeedregulatoroutputcurrentisgiven,theoutputamplitudeislimitedtothemaximumcurrentvalue.Adjustthelimitofsmallamplitudeorcurrent-feedbackcoefficientcanbeadjustedeasilytochangethemaximumcurrent.Ineffect,thebrakingprocess,thespeedregulatorquicklyintosaturation,theoutputamplitudelimitforthecurrentlooptoprovideamaximumcurrentsetting,thecurrentregulatorforthePIregulator,initsregulatoryroleunderthecurrentremainedatthemaximumwhenthesystemisinfactaconstant-current-conditioningsystem.Sincethecurrentloopsothattheregulatingroleofthesystem,thebrakingcurrenttransitionprocessinthebestformoftransitionclosertotheidealwaveform.Whenthespeedovershoot,thespeedregulatoroutofsaturation,onspeedplayamajorregulatoryrole,tobecomecurrentwiththecurrentloopcontrolsystem.2•3.Currentfeedbackloopallowsthesystemtoenhancetheanti-interferenceability,roleinthecurrentlooptothechannelontheroleofallthedisturbances,suchasdisturbancessuchasvoltage,currentloopbyregulatingthetimelyinhibited,sothatspeedisnotaffectedorlessaffectedbydisturbances.Currentspeedoftheinnerringalsoplayedinthetransformationofthetargetstructureandregulationoftheroleofparameterstoacceleratethespeedofadjustmentinresponsetotheprocessofring.Incharacteristics,thespeedoftheadjustmentringtoensurethesystemwithoutstaticerror,theroleofcurrentloopsystemwithbettersagcharacteristicsofanexcavator.•4.SystemSimulationMathWorksInc.MATLABisintroducedin1984asetofnumericalsimulationsoftware,isdividedintothetotalpackageandanumberofkits,youcanachievethenumericalanalysisDifferentbranchofmathematicsittofunctionintheformofalgorithmsclassifiedaslibraries,theuseofdirectcallstothesefunctionsandgivetheactualparametersoftheproblemcanbesolvedquicklyandaccurately.thatis,toaseriesofconnectingmodule,acomplexmodelofthesystem.Inrecentyears,wastheriseoftheSimulinkhasbecomeafieldofacademicandindustrial•Building,simulationandanalysisofdynamicsystemsonthemostwidelyusedsoftwarepackage,itsupportslinearandnon-linearsystems,couldcreateacontinuoustime,discrete-timesystemoramixtureofthetwomodels.Systemisalsoabletomulti-samplingfrequency(Multirate),whichisdifferentindifferentsystemscancombinethesamplingfrequency.SimulinkofMATLABasanadditionalcomponent,asystemusedtoprovidemostoftheworkofmodelingandsimulationplatform.Simulinkisawayofmodulesallowuserstoquicklyandaccuratelytocreatecomputermodelsofdynamicsystems,especiallyforcomplexnon-linear,anditseffectmorevisible.Simulinkmodelcanbeusedtosimulatethelinearornonlinear,orbothcontinuousordiscretehybridsystems,whichmeansitcanbeusedtosimulatealmostallofthedynamicsystemcanbeencountered.Inaddition,Simulinkprovidesagraphicalanimationapproachsothatuserscaneasilyobservethewholeprocessofsimulation.3译文•1.引言•1.1电气传动技术发展现状•三十多年来，直流电机传动经历了重大的变革。首先实现了整流器的更新换代，以晶闸管整流装置取代了习用已久的直流发电机电动机组及水银整流装置使直流电气传动完成一次大的跃进。同时，控制电路已经实现高集成化、小型化、高可靠性及低成本。以上技术应用，使直流调速系统的性能指标大幅提高，应用范围不断扩大。直流调速技术不断发展，走向成熟化、完善化、系列化、标准化，在可逆脉宽调速、高精度的电气传动领域中仍然难以替代。•1.2微机控制电机的发展和现状•比较简单的电机微机控制，只要用微机控制继电器或电子开关元件使电路开通或关断就可以了。在各种机床设备及生产流水线中，现在已普遍采用带微机的可编程控制器，按一定的规律控制各类电机的动作。对于复杂的电机控制,则要用微机控制电机的电压、电流、转矩、转速、转角等等,使电机按给定的指令准确工作。通过微机控制，可使电机的性能有很大的提高。•2单闭环控制直流脉宽调速系统•本章主要讨论单闭环直流调速系统。由于开环控制的直流调速系统静态转速降较大，不能满足调速指标的要求，因此需采用转速负反馈或电压负反馈组成闭环调速系统。但是单闭环系统并不能满足本课题调速系统的要求。•3微机控制双闭环可逆调速直流PWM调速系统原理设计4•转速、电流双闭环调速系统的两个调节器串级连接，转速反馈环为外环，电流环为内环。速度调节器的输出即为电流给定，其输出限幅值即为最大电流给定值。调整限幅值的小或调整电流反馈系数就可方便地改变最大电流。在起、制动过程中，速度调节器很快入饱和，输出限幅值为电流环提供了最大电流给定，电流调节器为PI调节器，在它的调节作用下使电流保持在最大值，这时系统实际上为一个恒值电流调节系统。由于电流环的调节作用使系统的起、制动过渡过程中电流的波形接近于理想的最佳过渡波形。当转速超调后，速度调节器退出饱和，对转速起主要调节作用，电流环成为电流随动系统。•电流反馈环使得系统的抗干扰能力增强，作用在电流环前向通道上的一切扰动作用，如电网电压扰动等，受到电流环的及时调节所抑制，使转速不受或少受扰动的影响。电流内环还起到改造转速外环中调节对象结构及参数的作用，加快了转速环的调节响应过程。在特性上，转速环的调节作用