直流无刷电机外文资料原文及译文

外文原文及译文外文资料原文CommutationTorqueRippleReductioninBLDCMotorUsingPWM_ON_PWMModeGuangweiMeng,HaoXiong,HuaishuLiDepartmentofElectricalEngineering,NavalUniversityofEngineering,Wuhan,China.Abstract--ThepaperanalyzesthesteadycommutationprocessoftheBLDCmotorusingPWMmode,confirmsthecommutationtimetokeepnoncommutationphasecurrentamplitudeconstantduringcommutationperiodbywayofPWMintheperiodtoimplementthecompensationcontroltoeliminatecommutationtorquerippleunderbothlowspeedandhighspeedoperation,investigatestheeffectbyPWMmodeonathree-phasesix-state120°turn-onBLDCmotor,andpresentstorqueripplecompensationcontrolinPWM_ON_PWMmode,whichcannotonlyentirelyeliminatetorquerippleresultedfromthecurrentemergingintheturn-offphaseduringnon-commutationperiodbutalsocompensatetorqueripplecausedbythecommutationcurrentduringcommutationperiod.IndexTerms—BLDCmotor,commutation,PWM,torqueripple.I.INTRODUCTIONTheBLDCmotorshavebeenwidelyusedduetoitsfeatures－asimplestructure,goodspeedadjustingperformance,highpowerdensity,lownoiseandsimplecontrol,etc.ItisahotspottosuppressthetorquerippleandimprovethecontrolperformanceofaBLDCmotorwiththetrapezoidalbackemf.BLDCmotorsusuallyoperateinallkindsofPWMmodes,whichnotonlyaffectthedynamiclossofpowerswitchesandradiationuniformity,butalsoinfluencethetorqueripple.Itisaneffectivewaytosuppressthetorqueripplethroughchangingdcbuschoppercontroltoremainnon-commutationphasecurrentamplitudeconstant,butitresultsintoamorecomplextopology[1]-[3].Itisjustfitforlowspeedapplicationstocontrolnon-commutationphasecurrentamplitudetoregulatethecommutationtorqueripple[4].ItisanalyzedabouttheinfluenceresultedfromPWMONmodeonthetorqueripplein[5].Theideasin[1]-[3]aretoadoptdifferentsuppressionmethodsindifferentspeedinterval,buttheydon’ttaketheeffectbyPWMmodesonthesysteminaccount.Thepredictivecurrent,neuralnetworkcontrolandactive外文原文及译文disturbancerejectioncontroletcareintroducedtosuppressthetorqueripplein[9]-[12],butthecontrolalgorithmismorecomplicatedandharderforrealization.DependingonthecommutationprocessofBLDCmotorsandtheeffectbyPWMmodesonthesystem,thepaperpresentsatorqueripplecom-pensationcontrolinPWM_ON_PWMmodeatdifferentspeedsbyseekingdifferentPWMmodulationratiosduringcommutationperiodasmotorrunsatlowspeedandhighspeed.Themethodretainstheoriginalto-pology,improvesthecontrolperformanceofthesystemdramatically,andmoreoveriseasytorealize.II.ELECTROMAGNETICTORQUEOFBLDCMOTORDURINGCOMMUTATIONPROCESSAssumethattheBLDCmotoristhree-phasesymmetricalandY-connected,andneglecteddycurrentsandhysteresislosses,itsequivalentcircuitandmaincircuitareshowninFigure1.r,Laretheresistanceandinductanceofthestatorwindingsrespectively;CBAeee,,arethecounteremfsofthecorrespondingphasewindingsrespectively;CBAiii,,arethecorrespondingphasecurrentsrespectively.0CBAiii(1)Thecounteremfofeveryphasewindingisatrapezoidalwaveformwithaflat-topwidthgreaterthanorequalto1200electricaldegree,anditsflat-topamplitudeisEm.Whenthemotorworksinthree-phasesix-state1200turn-onmode,thecurrentsdon’tcommutatesinstantaneouslyasaresultoftheinductanceofthearmaturewinding.Takethepowerswitch1Tand2T’sturn-onto2Tand3T’sturn-onforexample.Duringthecommutation,itisgainedasfollowsmCBAEeee(2)SupposethatthemechanicalangularvelocityoftherotorisΩ,thetoquecanbeobtainedasfollowsduringthecommutationprocess.外文原文及译文CmCCBBAAeiEieieieT2(3)Itisobviousfrom(3)thatthetoqueisproportionaltothenon-commutationphasecurrentduringcommutation,i.e.thecommutationtorqueripplecanbeeliminatedsolongasnon-commutationphasecurrentremainsconstantduringcommutation.III.COMMUTATIONPROCESSWITHOUTCONSIDERINGEFFECTBYPWMANDARMATUREWINDINGRESISTANTAssumethatthecircuitstatuschangesfromphaseAandC’sturn-ontophaseBandC’sturn-on,phaseAcurrentflows4Danddecaystozerogradually,whilephaseBcurrentincreasestothemaximumgraduallyandreachesitssteady-statevalue.ThecircuitequationduringcommutationwithoutconsideringtheeffectbyPWMcanbewrittenasfollows.dCCCBBBCCCAAAUeridtdiLeridtdiLeridtdiLeridtdiL)(0)((4)ComparedwiththewindingtimeconstantrLofaBLDCmotor,PWMperiodcanbethoughtsmallenough,andthenCBAXdidiLritXX,,.Sotheeffectofthearmaturewindingresistantcanbeneglected.Moreovertheinitialandfinalvaluesofeveryphasecurrentequaleveryphasesteady-statecurrentvalue0Ibeforeandafterthecommutation.Allphasecurrentsduringthecommutationcanbeobtainedfrom(1),(2)and(4).tLEUIitLEUitLEUIimdCmdBmdA34323200(5)ThenthetoqueduringthecommutationcanbewrittentLEUIETmdme3420(6)From(5),theturn-offtimeofft∼ofphaseAandtheturn-ontimeont∼ofphaseBduringthecommutationprocessaremdoffEULIt230~(7)外文原文及译文mdonEULIt230~(8)From(5)~(8),thecommutationbetweentwophasescan’tbecompletedinthesametimeasmdEU4,i.e.themotorspeedislessthanacertainvalue,andasaresultBihasreacheditssteady-statevaluebeforeAifallsto0,showninFig.2(I).What’smore,thecommutationleadstoanincreaseintheamplitudeoftorque.ThetorqueripplecanbeobtainedmdmdmrEUEUIET40(9)ThecommutationbetweentwophasescanbecompletedinthesametimeasmdEU4,i.e.Themotorrunsatacertainspeed,andasaresu