《车用驱动电机原理与控制基础 第2版》 课件 钟再敏 Chapter 7 Space Vector Description；Chapter 8 Control Methods and Their Implementation

Chapter7

SpaceVectorDescriptionandFieldOrientedControlofInductionMotors车用驱动电机原理与控制基础(第2版)PrincipleandControlFundamentalsofVehicleDriveMotorsa)

squirrelcagewindingb)

RotorstructureofwoundwindingFig.7-1Schematicdiagramofrotorstructureofinductionmotor27.1TheRotorStructureandWorkingPrincipleofIMThestatorstructureoftheinductionmotorisbasicallythesameasthatofthesynchronousmotor.Themaindifferenceliesintherotorstructureandthegenerationprincipleoftherotormagneticfield.Therotorstructureofinductionmotor(IM)mainlyincludestwoparts:rotorironcoreandrotorwinding.Thecommonwindingtypesaresquirrelcagetypeandwoundtype.1.SquirrelcagewindingAsquirrel-cagewindingisaself-closingshort-circuitwinding.Itconsistsofabarinsertedintoeachrotorslotandannularendringsatbothends.Iftheironcoreisremoved,theentirewindingislikea“circularsquirrelcage”.2.WoundwindingTheslotofthewoundrotorisembeddedwithathree-phasewindingcomposedofinsulatedwires.Thethreeoutgoingwiresofthewindingareconnectedtothethreecollectorringsmountedontheshaft,andareconnectedtotheexternalcircuitthroughbrushes.Thefeatureofthisrotoristhatanexternaladjustableresistorcanbeconnectedtotherotorwindingtoimprovethestartingandspeedregulationperformanceofthemotor.37.1.2WorkingPrincipleofThree-phaseIMThestatorisathree-phasesymmetricalwinding,anditsstructureisthesameasthatofathree-phasesynchronousmotor.Atthesametime,therotorisalsoequivalenttothree-phasesymmetricalwindingsa-x,b-yandc-z,andtheyareshort-circuited,thusformingabasicthree-phaseinductionmotor

Fig.7-2aTheequivalentphysicalmodelofthe

three-phaseinductionmotor4

7.1.2WorkingPrincipleofThree-phaseIM57.1.3Stator,RotorandMagneticFieldSynchronousCoordinateSystems

Table7-1Therepresentationandtransformationrelationshipsofcurrentvectorsinthreecoordinatesystems67.2VectorsEquationofIM7.2.1Stator/RotorInductanceandFluxLinkageofIM

Fig.7-3Theequivalentfour-coilprototypemotormodelofIM77.2.1Stator/RotorInductanceandFluxLinkageofIMFig.7-4Thestator/rotorcurrent,andrespectivefluxlinkagevectorsofthethree-phaseIM87.2.2SpaceVectorEquationsunderStationaryReferenceFrame

9

7.2.3SpaceVectorEquationsunderRotor-fixedabcReferenceFrame107.2.4SpaceVectorEquationunderArbitraryMagneticFieldSynchronousRotatingMTReferenceFrame

11

7.2.4SpaceVectorEquationunderArbitraryMagneticFieldSynchronousRotatingMTReferenceFrame12

7.2.4SpaceVectorEquationunderArbitraryMagneticFieldSynchronousRotatingMTReferenceFrame13

7.2.4SpaceVectorEquationunderArbitraryMagneticFieldSynchronousRotatingMTReferenceFrame14Fig.7-5Steady-statevectordiagramofthethree-phaseIM7.2.4SpaceVectorEquationunderArbitraryMagneticFieldSynchronousRotatingMTReferenceFrame157.3RotorMagneticFieldEstablishmentProcessandItsOrientationFig.7-6Therotormagneticfieldisrepresentedasthecombinationoftheair-gapmagneticfieldandtherotorleakagemagneticfield

167.3RotorMagneticFieldEstablishmentProcessandItsOrientationFig.7-6Therotormagneticfieldisrepresentedasthecombinationoftheair-gapmagneticfieldandtherotorleakagemagneticfield

177.3.1Rotort-axisMagnetomotiveForceInducedbyMotionalElectromotiveForceFig.7-7Therotorequivalentcurrentvectorwhentherotormagneticfieldamplitudeisconstanta)Rotormagnetomotiveforcevectorformedbyrotorbarcurrent

b)Thespatialdistributionofmotionalelectromotiveforceandcurrentmagnitudeintheconductor18Fig.7-8

Therotorequivalentcurrentvectorwhentheamplitudeoftherotormagneticfieldisconstanta)Themagnetomotiveforcevectorsoftherotorcoilcurrentsandtheirsynthesisb)Theequivalentexcitationcurrentatt-axis

7.3.1Rotort-axisMagnetomotiveForceInducedbyMotionalElectromotiveForce

19Fig.7-9RotorcurrentvectorwhenrotormagneticfieldamplitudechangesDuringthedynamicoperationofthemotor,iftheamplitudeoftherotormagneticfieldchanges,transformerelectromotiveforcewillbeinducedineachrotorbar.AtthemomentshowninFig.7-9a,iftheamplitudeoftherotormagneticfieldisincreasing,accordingtoLenz'slaw,theelectromotiveforceineachbarwillbeshowninFig.7-9a.

7.3.1Rotorm-axisMagnetomotiveForceInducedbyInducedElectromotiveForcea)Rotorcurrentandrotormagnetomotiveforceb)Spatialdistributionoftransformerelectromotiveforceandcurrentmagnitudeinthebar207.3.3DefinitionandCharacteristicsofRotorMagneticField-OrientedCoordinateSystemFig.7-11RotorcagewindingisequivalenttoMTaxiscoilFig.7-12MagneticfieldorientedMTcoordinatesystem

217.3.4StatorandRotorFluxLinkageEquation

227.3.6StatorandRotorVoltageEquations

237.3.6StatorandRotorCurrentEquations

247.3.6StatorandRotorCurrentEquations

257.3.6StatorandRotorCurrentEquationsFig.7-13Vectordiagramofmagneticfluxandcurrentforathree-phaseinductionmotorafterfieldorientation

a)Dynamicvectordiagramoffluxlinkageandcurrent267.3.7TorqueEquation

27

7.3.7TorqueEquation287.3.7TorqueEquation

297.4PrincipleofVectorControlbasedonCurrentPhasePlane7.4.1ControlConstraints

307.4.1ControlConstraintsonCurrentPhasePlane

317.4.1ControlConstraintsonCurrentPhasePlane

Fig.7-18Thediagramsofcontrolconstraintsandcontrollawforinductionmotor327.4.1ControlConstraintsonCurrentPhasePlane

337.4.2FieldWeakeningControlProcessonCurrentPhasePlaneFig.7-19OperatingregionoftheinductionmotoracrossthefullspeedrangeThefieldweakeningcontroloftheinductionmotorshouldaimforthemaximumtorqueoutput,takingintoaccounttheconstraintsofvoltageandcurrenttoallocatethecurrentreasonably.Duetothesevoltageandcurrentconstraints,theeffectivetorqueoutputoftheinductionmotordecreasesinthefieldweakeningregion.Tofullyutilizethemaximumtorquecapabilityofthedrivesystemundervoltageandcurrentlimitations,themostrationalutilizationofvoltageandcurrentisrequired.Theoperatingspeedrangeofaninductionmotorcanbedividedintothreeregions:constanttorqueregion,constantpowerregion,andconstantvoltageregion,asshowninFig.7-19.Whenthemotorspeedislessthanthebasespeedoffieldweakening,sincethegeneratedbackelectromotiveforceislessthanthemaximumvoltageoutputbytheinverter,themotoroperationisonlylimitedbythemaximumcurrentallowedbythemotor,andthemaximumoutputtorquecanremainunchanged.Therefore,thisareaisnamedasthe“constanttorquearea”.Abovethefieldweakeningbasespeed,themotorentersthefieldweakeningregion,wherethebackelectromotiveforceisalmostequaltothemaximumvoltageoutputoftheinverter.Themotoroperationisconstrainedbyboththemaximumcurrentandmaximumvoltage,buttheoutputpowerremainsconstant,henceitiscalledthe“constantpowerregion”.Asthemotorspeedcontinuestoincrease,thecurrentcannotbemaintainedatitsmaximumvalueduetothelimitationofthemaximumsliprate.Atthispoint,themotorisonlyconstrainedbythemaximumvoltage,andbothoutputpowerandtorquedecreasesharplywithincreasingspeed,thusitiscalledthe“constantvoltageregion”.Chapter7

SpaceVectorDescriptionandFieldOrientedControlofInductionMotors车用驱动电机原理与控制基础(第2版)PrincipleandControlFundamentalsofVehicleDriveMotorsChapter8

ControlMethodsandTheirImplementationofVehicleDriveMotors车用驱动电机原理与控制基础(第2版)PrincipleandControlFundamentalsofVehicleDriveMotors368.1PrincipleofField-OrientedControl(FOC)Thefour-coilprototypemotoroffersmorecontrolfreedom.Takingstatorcontrolasanexample,thebasicvectorcontrolarchitectureofthefour-coilprototypemotorisshowninFig.8-1.Thiscontrolstructureisbasedonthespacevectorform.Fig.8-1Basicvectorcontrolarchitectureofthefour-coilprototypemotor

378.1PrincipleofField-OrientedControl(FOC)

Fig.8-2FOCstructureofthePMSM388.1PrincipleofField-OrientedControl(FOC)IncontrasttoPMSM,thegenerationoftherotormagneticfluxininductionmotorsarisesfromtheexcitationofthestatorcurrent.Therefore,unlikePMSM,inrotormagneticfieldorientationvectorcontrol,thedirectionoftherotormagneticfieldcannotbedetectedsimplybysensingthemechanicalpositionoftherotor.Itrequiresanalysisandestimationoftherotormagneticfluxbasedonsignalssuchasstatorcurrent,rotorspeed,andstatorvoltage.Theestimationmethodforrotormagneticfluxcanbereferredtothevoltage-currentmodeorcurrent-speedmodelintroducedinSection8.6.OtherissuesregardingFOCininductionmotorareessentiallysimilartothoseinPMSM.Fig.8-3FOCstructureoftheinductionmotor39Three-PhaseACPower

408.2PulseWidthModulation(PWM)InverterandSpaceVectorModulation8.2.1BasicStatorVoltageVector

Fig.8-4StatorVoltageVector-WindingsarepoweredbytheinverterItisdefinedthatwhentheuppertubeofabridgearmisinthe“on”state,theswitchstateofthebridgearmis“1”;whenthelowertubeofthebridgearmis“on”,theswitchstateis“0”.Inthisway,thethreebridgearmstatecombinationshaveatotalofeightstatesof000,001,010,011,100,101,110,and111,whicharecalledeight“basicvoltagespacevectors”(referredtoas“voltagebasisvectors”).Amongthem,000and111maketheinverteroutputvoltagezero,sothesetwoswitchingmodesarecalledzerostates.418.2.1BasicStatorVoltageVector

Fig.8-5Statorvoltagevector(100vector)428.2.1BasicStatorVoltageVector

Fig.8-6Thebasicvoltagespacevectors438.2.2Volt-SecondEquivalencePrincipleandSVPWMFig.8-7SynthesisofSpaceVoltageVectors

44SVPWMVoltageVectorInscribedCircle内切矢量圆

458.2.2Volt-SecondEquivalencePrincipleandSVPWM

Fig.8-8basicvoltagespacevectors468.2.2Volt-SecondEquivalencePrincipleandSVPWM

Fig.8-9StatorreferencevoltagevectorsynthesisInthesecondstep,afterthesectorisdetermined,thevoltagecommandissynthesizedfromthenon-zerovoltagebasevectorandzerovoltagevectorthatcomposethesector.478.2.2Volt-SecondEquivalencePrincipleandSVPWMFig.8-10Thefirstsectorvoltagecommandthree-phasePWMwaveform

48AVideotoIllustrateGenerationProcessofSVPWM49

Commonemitterconnectionandvolt-amperecharacteristicsofNPNtransistors

8.4PowerSemiconductorDevices-GTR50

FieldEffectTransistor(FET)isadevicethatcontrolstheconductivityofasemiconductorbychangingtheelectricfieldthroughthechannel.Thecurrentpassingthroughitchangeswiththestrengthoftheelectricfield.Ithastwotypes:junctiontypeandsurfacetype.TheformerisbasedonthePNjunction,andthelattercontrolsthecurrentinthechannelwiththesurfaceelectricfield.

Theelectricfieldoftheinsulatinglayeriscontrolledbyanappliedvoltagetochangethesurfacefieldeffectofthechannelconductanceinthesemiconductor,soitisalsocalledaninsulatedgatefieldeffecttransistor.

Dependingonthematerialusedfortheinsulatinglayer,therearevarioustypesofIGFETs.

Atpresent,themostwidelyusedmetal-oxide-semiconductorfieldeffecttransistor(MOSFET)orMOStubeforshort.SchematicdiagramofpowerMOSFETunitstructureElectricalgraphicsymbolsforMOSFETs8.4PowerSemiconductorDevices-MOSFET518.4PowerSemiconductorDevices-MOSFET

Commonemittercircuit,outputcharacteristicsandtransfercharacteristicsofn-channelenhancement-modeP-MOSFETa)b)c)52

Commonemittercircuit,outputcharacteristicsandtransfercharacteristicsofn-channelenhancement-modeP-MOSFET8.4PowerSemiconductorDevices-MOSFET538.4PowerSemiconductorDevices-MOSFET

548.4PowerSemiconductorDevices-IGBTSchematicdiagram,symbolandequivalentcircuitofIGBT

558.4PowerSemiconductorDevices-IGBTThevolt-amperecharacteristicsandshort-circuitcharacteristicsofIGBTs

568.4PowerSemiconductorDevicesThedevelopmentofsemiconductormaterialscanbedividedintothefollowingstages:1)SiandGerepresentthefirstgenerationofsemiconductormaterials.2)GaAs(galliumarsenide),AlAs,andsimilarmaterialsdevelopedinthe1960sareconsideredthesecondgenerationofsemiconductormaterials.3)Inthepasttwodecades,thethirdgenerationofwidebandgapsemiconductormaterials,primarilySiCandGaN,hasgraduallyemerged.Thebandgapwidthofsiliconcarbide(SiC)isaboutthreetimesthatofsilicon(Si)material,givingSiCsignificantadvantagesoverSiintermsofvoltageresistanceandhigh-temperaturetolerance.Additionally,SiCdevicesexhibitmuchlowerleakagecurrentscomparedtoSidevices.Consequently,SiCdevicescanoperateinharshenvironmentssuchashightemperaturesandhighradiation.Table8-4PhysicalPropertiesofMajorPowerSemiconductorMaterials578.5IntegratedTechnologiesforAutomotiveMotorControllersThecompositionofthevehiclemotorcontrollerincludeshardwareandsoftware.Thehardwaremainlyincludesthemainpartssuchaspowercircuit,controlcircuitandstructuralheatdissipation.Thehardwaremainlyincludesthemainpartssuchaspowercircuit,controlcircuitandstructuralheatdissipation.

ThesoftwareincludesthesoftwareofthecontrolcircuitMCUandthesoftwareoftheprogrammablelogicdeviceintheprotectioncircuit.

Thepowercircuitmainlyincludespowermodules,capacitors,powerbusbars,etc.Exampleofcompositionofvehiclemotorcontroller58Audi-EtronMotorController59Thedemandcharacteristicsforautomotivepowermodulescanbesummarizedasfollows:1)WideTemperatureCharacteristics:Oneofthemostimportantandchallengingtechnicalrequirementsforpowermodulesinautomotiveapplicationsistheabilitytooperatenormallyatambienttemperaturesupto105°Cwithoutdegradingperformanceorreducingthelifespanofthemodule.2)ComplexOperatingConditions:Unlikeindustrialapplicationsinvolvingmotordrives,theoperatingconditionsforelectricvehiclesaremorecomplex.Forexample,inurbandrivingconditions,thevehiclefrequentlytransitionsbetweenacceleration,deceleration,andcruisingstates.3)HighReliabilityRequirements:Automotivepowermodulesmustmatchthelifespanofthevehicle,placinghigherdemandsonthedurabilityoftheIGBT.Typically,theoperationallifespanofapowermoduleis15yearsormore.Themainfactorsinfluencingpowermodulefailureincludepowercycling,thermalcycling,andvibration.Theselectionofpowermodulesforautomotiveelectricdrivesystemsmainlyconsidersthefollowingaspects:1)RatedVoltageandRatedCurrent:FormostA0-classandhighernewenergyvehicles,exceptforthosewithminimalhybridization,theratedvoltageofthepowerbatterypackisgenerallyaround300V.Duringbrakingorcharging,thebatteryvoltagemayriseabove400V.2)SwitchingFrequencyandSwitchingLoss:Increasingtheswitchingfrequencycanimprovethepowerdensityofthemotorcontroller,reducethesizeofthefilter,andminimizeoreliminatethesnubbercircuit,therebyreducingtheoverallsizeandweightofthecontroller.Additionally,itcangenerateelectromagneticinterference(EMC)noise.3)DynamicCharacteristicsandDeviceProtection:Theswitchingdevicesshouldbecapableofwithstandinghighvoltage/currentchangerates.Thedrivingpowerofthedeviceshouldbeverysmall,whichrequiresthedevicetohaveaverylowinputcapacitanceandveryhighinputimpedance(severalMΩormore).4)Cost:Thepriceofpowermodulescanaccountfor30-40%ofthetotalcostoftheinverter.Therefore,itisessentialtochoosedeviceswithahighperformance-to-priceratiowheneverpossible.8.5IntegratedTechnologiesforAutomotiveMotorControllers60DrivingCircuit61TheFunctionsofDrivingCircuitThefunctionsofdrivingcircuit:poweramplification,isolation,andwaveformadjustment628.5IntegratedTechnologiesforAutomotiveMotorControllersSchematicdiagramofatypicalelectricalisolationmethodTheIGBTdrivecircuitistheinterfacebetweenthelow-voltagecontrolcircuitandthehigh-voltagemaincircuit,andmainlyplaystheroleofdrivingpoweramplificationandprotectingpowerdevices.IthasanimportantinfluenceontheswitchingcharacteristicsoftheIGBT,includingswitchingspeed,switchinglosses,peaksandoscillationsofthewaveform,etc.Thedrivecircuitisanimportantlinkconnectingthecontrolcircuitandthepowercircuit,andshouldplaytheroleofhighandlowvoltageelectricalisolation.Atpresent,mainstreamdrivecircuitscanbedividedintothreecategoriesaccordingtoisolationmethods:opticalisolation,magneticisolation,andcapacitiveisolation.1）

Optocouplerisolationdriver：Theopto-isolateddriverusuallyusesanoptocouplertoachieveelectricalisolation.Sincetheoptocouplerisolationcanonlytransmitsignalsinonedirection,thehigh-frequencyinterferencesignalonthesecondarysidewillnotaffecttheprimaryside,soithastheadvantagesofstronganti-interferenceabilityandstableoperation.

2）

Magneticallyisolateddrive：Themagneticisolationdriveadoptstheisolationmethodofthepulsetransformer,andthesignalandenergyaretransmittedthroughthemagneticfield.

3）

Capacitiveisolateddrive：Capacitiveisolationdrivesusecapacitorsforisolationanduseelectricfieldstotransmitsignals.。638.5IntegratedTechnologiesforAutomotiveMotorControllersThecommonlyusedautomotivefiltercapacitorsaremainlydividedintotwocategories:electrolyticcapacitorsandfilmcapacitors.Tofurtherreducethesizeandweightofinvertersandmeettherequirementsofwidevoltagerangeandhigh-powerapplications,acompact,low-loss,cost-effectiveDC-Linkcapacitorisneeded.Comparedtoelectrolyticcapacitors,filmcapacitorshavethefollowingadvantages:ExcellentTemperatureCharacteristics:DC-Linkfilmcapacitorsusehigh-temperaturepolypropylenefilm,offeringgoodtemperaturestability.Incontrast,thecapacitanceofelectrolyticcapacitorsdropssharplyatlowtemperatures,affectingtheirapplicationincoldenvironments.AbilitytoWithstandReverseVoltage:Ifareversevoltageexceedingthespecifiedvalueisappliedtoanelectrolyticcapacitor,achemicalreactionoccursinsidethecapacitor,potentiallycausinganexplosionorelectrolyteleakageasinternalpressureisreleased.Filmcapacitors,beingnon-polar,canwithstandbidirectionalvoltagesurges,offeringhigherreliability.StrongPulseVoltageResistance:Filmcapacitorshavebetterimpactvoltageresistancecomparedtoelectrolyticcapacitors.DryDesign,NoElectrolyteLeakage:Filmcapacitorsdonothaveissueswithelectrolyteleakageandacidpollution.LowESRandHighRippleCurrentCapability:Filmcapacitorstypicallyhavelowerequivalentseriesresistance(ESR),witharipplecurrentcapabilityofupto200mA/pF.Incontrast,electrolyticcapacitorshavemuchlowerripplecurrentcapability.LowESL:Thelowinductancedesignofinvertersrequiresthemaincomponent,theDC-Linkcapacitor,tohaveextremelylowequivalentseriesinductance(ESL).High-performanceDC-Linkfilmcapacitorsintegratethebusbarintothecapacitormodule,reducingself-inductanceandminimizingoscillationeffectsatoperatingswitchingfrequencies.LongServiceLife:Filmcapacitorshavealongerservicelifeunderratedvoltageandratedoperatingtemperatureconditions.648.5IntegratedTechnologiesforAutomotiveMotorControllers

MotorControllerCoolingSystemThermalResistanceCircuitEquivalentThevehiclemotorcontrollerismainlyliquid-cooled,andtheheatingelementiscooledmainlybyconductionheatdissipation.

Thepowermoduleofthevehiclemotorcontrolleradoptsacompactarrangement,andthepowermodulecanbeapproximatelyconsideredasasingleheatsource;atthesametime,thecoolingsystemadoptsanoptimizeddesignscheme,sothattheheatofthecoolingsystemcanbedissipatedintime,soitcanbeconsideredasaradiatorforthemotorcontroller.65

Halltypecurrentdetectionprinciple8.5IntegratedTechnologiesforAutomotiveMotorControllers668.5IntegratedTechnologiesforAutomotiveMotorControllers

Fig.8-26CurrentDetectionPrincipleBasedonSamplingResistor678.5IntegratedTechnologiesforAutomotiveMotorControllersSchematicdiagramofMCUworkingmodeconversionThefollowingexamplesillustratetypicalsoftwarefunctionmodules.（1）

MotorControlStateMachineDesign.

Theintroductionofstatemachine(StateMachine)isverynecessaryforconcurrenttaskapplications.Itcanensurethattheembeddedcontrollermakesareasonable/timelyresponsetoexternalinputbydividingdifferentworkingmodes.

Thestateofthemotorcanbedividedinto:Initialization、Standby、HVActive、SpdqCtl、TrqCtl、DisCharge、Failure.（2）

Motortorquecontrolfunction.

TorquecontrolmeansthattheMCUreceivesthetorquecontrolrequestsentbythehostcomputer,andoutputsthetorquethatmatchestheworkingconditionswhileconsideringtheworkingconditionsofthemotorsystem(voltage,speed,temperature).Thetorquecontrolandfunctionrealizationofthedrivemotormainlyincludethemaximumtorquetocurrentratio(MTPA)controlinthelow-speedconstanttorquecontrolarea,theconstantpowerfieldweakeningcontrolinthehigh-speedarea,thespeedcontrol,andthevoltagecontrol.（3）

Communicationmodulesandotherfunctions.

TheelectronicstructureofmodernautomobilesismainlytoconnectdifferentECUsthroughtheCANbuscommunicationsystemtoformadistributedcontrolsystem.68PMSM

V.S.InductionMotorPMSM

orientationInductionMotororientation

SelectingthearbitrarymagneticfieldsynchronousMTcoordinatesystemtotherotorDQcoordinatesystem.

698.6RotorMagneticFieldPositionMeasurementandEstimationforACMotors8.6.1TypicalMotorPositionandSpeedMeasur