无刷直流电机控制器的软件设计中英文翻译

1、LDCCommutationTorqueRippleReductioninMotorUsingPWM_ON_PWMModeGuangweiMeng,HaoXiong,HuaishuLiDepartmentofElectricalEngineering,NavalUniversityofEngineering,Wuhan,China.Abstract:ThepaperanalyzesthesteadycommutationprocessoftheBLDCmotorusingPWMmode,confirmsthecommutationtimetokeepnoncommutationphasecur

2、rentamplitudeconstantduringcommutationperiodbywayofPWMintheperiodtoimplementthecompensationcontroltoeliminatecommutationtorquerippleunderbothlowspeedandhighspeedoperation,investigatestheeffectbyPWMmodeonathree-phasesix-state120°turn-onBLDCmotor,andpresentstorqueripplecompensationcontrolinPWM_ON

3、_PWMmode,whichcannotonlyentirelyeliminatetorquerippleresultedfromthecurrentemergingintheturn-offphaseduringnon-commutationperiodbutalsocompensatetorqueripplecausedbythecommutationcurrentduringcommutationperiod.IndexTermsBLDCmotor,commutation,PWM,torqueripple.I. INTRODUCTIONTheBLDCmotorshavebeenwidel

4、yusedduetoitsfeaturesasimplestructure,goodspeedadjustingperformance,highpowerdensity,lownoiseandsimplecontrol,etc.ItisahotspottosuppressthetorquerippleandimprovethecontrolperformanceofaBLDCmotorwiththetrapezoidalbackemf.BLDCmotorsusuallyoperateinallkindsofPWMmodes,whichnotonlyaffectthedynamiclossofp

5、owerswitchesandradiationuniformity,butalsoinfluencethetorqueripple.Itisaneffectivewaytosuppressthetorqueripplethroughchangingdcbuschoppercontroltoremainnon-commutationphasecurrentamplitudeconstant,butitresultsintoamorecomplextopology1-3.Itisjustfitforlowspeedapplicationstocontrolnon-commutationphase

6、currentamplitudetoregulatethecommutationtorqueripple.ItisanalyzedabouttheinfluenceresultedfromPWMONmodeonthetorqueripple.Theideasin1-3aretoadoptdifferentsuppressionmethodsindifferentspeedinterval,buttheydonheeffettOdyePWMmodesonthesysteminaccount.Thepredictivecurrent,neuralnetworkcontrolandactivedis

7、turbancerejectioncontroletcareintroducedtosuppressthetorqueripple,butthecontrolalgorithmismorecomplicatedandharderforrealization.DependingonthecommutationprocessofBLDCmotorsandtheeffectbyPWMmodesonthesystem,thepaperpresentsatorqueripplecom-pensationcontrolinPWM_ON_PWMmodeatdifferentspeedsbyseekingdi

8、fferentPWMmodulationratiosduringcommutationperiodasmotorrunsatlowspeedandhighspeed.Themethodretainstheoriginalto-pology,improvesthecontrolperformanceofthesystemdramatically,andmoreoveriseasytorealize.II. ELECTROMAGNETICTORQUEOFBLDCMOTORDURINGCOMMUTATIONPROCESSFie.1Block:diazramofathree-phaseBUX.moto

9、randitstvstemAssumethattheBLDCmotoristhree-phasesymmetricalandY-connected,andneglecteddycurrentsandhysteresislosses,itsequivalentcircuitandmaincircuitareshowninFigure1.r,Laretheresistanceandinductanceofthestatorwindingsrespectively;eA,eB,eCarethecounteremfsofthecorrespondingphasewindingsrespectively

10、;iA,iB,iCarethecorrespondingphasecurrentsrespectively.iAiBiC=0(1)Thecounteremfofeveryphasewindingisatrapezoidalwaveformwithaflat-topwidthgreaterthanorequalto1200electricaldegree,anditsflat-topamplitudeisEm.Whenthemotorworksinthree-phasesix-state1200turn-onmode,thecurrentsdon'commutatesinstantane

11、ouslyasaresultoftheinductanceofthearmaturewinding.TakethepowerswitchT1andT2'turn-ontoT2andT3'sturonforexample.Duringthecommutation,itisgainedasfollowsQ,thetoquecanbeeA=eB-ec=EmSupposethatthemechanicalangularvelocityoftherotorisobtainedasfollowsduringthecommutationprocess.Te=ejAeBiBecic2EmicI

12、tisobviousfrom(3)thatthetoqueisproportionaltothenon-commutationphasecurrentduringcommutation,i.e.thecommutationtorqueripplecanbeeliminatedsolongasnon-commutationphasecurrentremainsconstantduringcommutation.IIITORQUERIPPLEREDUCTIONINPWMMODEanewPWMmodeispresentedPWM_ON_PWM,i.e.usingPWMmodeinthefirst30

13、andthelast30whilekeepingconstantturn-onmodeinthemiddle60.Themodecanentirelyeliminatetheemergingcurrentintheturn-offphaseduringnon-commutationandthusreducethetorquerippleduringnon-commutation.PWM_ON_PWMisabilateralmodulation,butthedynamiclossesofpowerswitchesinthemodeareequaltothoseofunilateralmodula

14、tion.Sixswitchesaremodulatedinturn,sothepowerswitcheshaveauniformradiationandthesystemhasahigherreliability.ThemodeisemployingPWMontheturn-onpowerswitchesandthusitcansuppressthetorquerippleduringcommutationtoacertainextentevenifacompensationcontrolisnotappliedatalowspeed.InPWM_ON_PWMmode,itcannotonl

15、yeliminatethetorquerippleduringnon-commutationbutalsosuppressthecommutationtorquerippleatlowspeed4Em3rI0.，一operationbykeepingDBB=inthecommutationcompensationcontrolUdtimetc=Lln1+crrI0rI°+2Em)atlowspeedoperation,i.e.4Em3rI0Ud.Athighspeedoperationi.e.4Em3rI0-Udoverlappingcommutationisusedtokeepth

16、eturn-onphaseconstantlyonandmakethecontrolpulsedutycycleoftheturn-off_4Em3rI0phaseDAA=-1inthecommutationcompensationcontroltimeUdLtc=ln1-rUd-2Em-rI0,whichcannotonlyeliminatethetorquerippleduringnoncommutationbutalsosuppressthecommutationtorquerippleathighspeedoperation.Asimulationiscarriedouttoverif

17、ythemethod.TheparametersareL=26mH,r=0.66C,J=0.0157kgm2,UN=48V,nN=1600rmi,TL=0.4N.Innon-full-bridgemodulationmodesuchasH_PWM-L_ONmode,powerswitchesintheupperarmsusePWMmodewhiletheothersinthelowerarmsuseconstantturn-onmodein1200turn-oninterval.ThesimulationwaveformofphasecurrentisshowninFig.3.Itisobvi

18、ousthatacurrentemergesintheturn-offphaseduringnon-turn-onperiodanditspulsatingfrequencyisthesameasthemodulatingfrequencywhileitsamplitudevarieswiththevariationofbackemfamplitude,whichproducesareversetorque.DL7CL7BQ.BHS>口9OJ951Figure2H_PWM-L_ONphasecurrentwaveformD.Sojo.tsosass口r。彩1WRFigure3PWM_ON

19、_PWMphasecurrentwaveformThesimulationwaveformofphasecurrentinPWM_ON_PWMmodeisshowninFig.4.Itisobviousthatnocurrentemergesintheturn-offphaseduringnon-turnonperiod,whichreducesthetorquerippleduringnoncommutationcomparedwithotherPWMmode.Fig.5showsthewaveformsofthephasecurrentandtorqueatlowspeedwithPWMp

20、ulsedutycycleDA=0.2withoutcompensationcontrol.Fig.6showsthewaveformsofthephasecurrentandtorqueatlowspeedwiththecontrolpulsedutycycleDBB=0.4intheturn-onphasewithinthecommutationtimetc=0.0013byacompensationcontrol.Thecomparisonindicatesthatthetorqueripplecausedbycommutationcanbealmosteliminatedbymeans

21、ofacommutationcompensationcontrolatlowspeedapplication.ItisfoundfromFig.3toFig.8thatusingacommutationcompensationcontrolinPWM_ON_PWMmodecannotonlyavoidthetorqueripplecausedbytheemergingcurrentintheturn-offphaseduringnoncommutationbutalsoeffectivelysuppressthecommutationtorquerippleatbothlowspeedandh

22、ighspeedapplications.IIIII4B1+I07asatiuu1弊Figure5whenrunningatlowspeedbychangingthephasecurrentandphasecompensationtorquewaveformFigure4phasecurrentandtorquewaveformduringLowspeedrunningFigure6underthespeedofphasecurrentandtorquewaveform0.5f口a.E0.74O.7B也S2b'S口E0-CL720.74；业7B。内O.S2VSFigure7high-s

23、peedrunthroughthecompensationcontrolofphasecurrentandtorquewaveformIV.CONCLUSIONSBasedontheanalysisofcommutationprocessofBLDCmotorandtheeffectbyPWMmodeonthecontrolsystem,acommutationcompensationcontrolinPWM_ON_PWMmodeisworkedout,whichcannotonlyeliminatetorquerippleresultedfromthecurrentemerginginthe

24、turn-offphaseduringnon-commutationperiodbutalsocompensatecommutationtorqueripple.Acontrolsystemwithouttorqueripplecanberealizedthroughthemethodunderbothlowspeedandhighspeedoperation.REFERENCES1 S.Wang,T.Li,andZ.Wang,"CommutationtorqueripplereductioninbrushlessDCmotordrivesusingasinglecurrentsen

25、sor,“ElectricMachinesandControl,vol.12,pp.288-293,March.2008.2 X.Zhangand乙Lu,“NewBLDCMdrivemethodtosmooththetorque,"PowerElectronics,vol.41,pp.102-104,Feb.2007.3 H.J.SongandC.Ick."CommutationtorqueripplereductioninbrushlessDCmotordriversusingasingleDCcurrentsensor"IEEETrans.OnPowerEle

26、ctr,vol.19,pp.312-319,Feb.2004.4 G.H.Kim,J.SeogandS.W.Jong,“AnalysisfthecommutationtorquerippleeffectforBLDCMfedbyHCRPWM-VSI,"Proc.ofAPEC'92,1992,-282775 X.ZhangandB.Chen,“ThedifferentinfluencesoffourPWMmodesoncommutationtorqueripplesinbrushlessDCmotorcontrolsystem,“ElectricMachinesandContr

27、ol,vol.7,pp.87-91,Feb.2003.6 D.Chen,Z.LiuandJ.Renetal,?AnalysisofeffectsonBLDCMtorqueripplebyPWMmodes:.ElectricalDrivers,vol.35,pp.1820,April2005.中文翻译用pwm_on_pWM抑制无刷直流电机换相引起的脉动转矩中国武汉海军工程大学电机工程系蒙广伟、雄郝、李怀树编摘要：本文分析了无刷直流电动机采用PWM空制稳定换相的过程，证实了运用PWMg式，在换相时控制非换相相电流有稳定不变的幅度，并进行补偿以消除低速和高速工作下的换相转矩脉动；研究了运用三相六状态

28、的PWIMI式1200启动无刷直流电机的方法，并提出基于脉宽调制的PWMK式如何来抑制转矩脉动，PWM控制不仅可以消除非换相期间由关断电流引起的转矩脉动，还可以补偿换相期间由换相电流引起的转矩脉动。关键词：直流无刷电机、换相、PW脉宽调制、转矩波动1 .前言由于直流无刷电机具备结构简单、调速性能好、功率密度高、噪音低、控制简便等优点，现已得到广泛的运用。用梯形反电动势法抑制转矩脉动和完善直流无刷电机控制性能已成为一个热点。直流无刷电机经常运转在各种PWMK式，PWMf仅影响着电力开关的动态损耗和辐射均匀性，也影响着转矩脉动。通过直流母线波纹斩波，抑制转矩脉动以稳定非换相相电流幅值恒定是很有效的

29、方式，但这导致了一个更复杂的拓扑结构式（1）式（3）,它只适用于低速运作场合，通过控制非换相相电流幅值来控制转矩脉动。分析PWMg式下转矩脉动的作用，式（1）式（3）中的观点是在不同的速度区间采用不同的抑制方法，但没有起到PWMW作用。目前预测，神经网络控制和主动自抗扰控制等的引入，能达到抑制转矩脉动的效果，但控制算法更复杂也更难实现。根据直流无刷电机换相问题和PWMS制方式在系统中的影响，提出了一种控制转矩脉动补偿模式-pwm_on_pWM式，寻求在不同的速度下通过寻求不同的PWMB制比，来保证电机在低速和高速状态下稳定转动。该方法保留了原有的拓扑结构，显著提高了该系统的控制性能，而且很容易

30、做到。2 .无刷直流电动机换相过程中的电磁转矩图1三相无刷直流电动机及其系统图假设直流无刷电机是三相对称Y联接，忽略涡流和磁滞损耗，具等效电路和主要电路如图1所示，R,L分别是电阻和定子绕组电感，eA，eB，ec分别是相应阶段的绕组反电动势，iA,iB,ic分别是相应的相电流：iABQ=。(1)每相绕组的反电动势是平顶宽度大于或等于120度的梯形波，其平顶振幅是Em当电机工作在三相六阶段120度导通模式下，电流不整流瞬间电枢绕组做电感处理。例如图中工和T2导通，到T2和T3导通。换相时有如下关系：eA二兔-%=Em(2)假设转子机械角速度为Q,在换相过程中可获得的转矩如下：eAiAeBiBeC

31、iC2EmiC/qTe=(3)e二二很显然，从式(3)可以看出在换相期间转矩与非换相相电流成比例关系，即只要换相时非换相相电流保持不变，就可以消除转矩脉动。3 .PWM莫式降低转矩脉动在公式的基础上，一个新的PWM勺控制方式一PWM_ON_P皿提出了，这种控制方式是在第一个30度和最后一个30度里采用PW雕制，同时保持转速在中间的60度范围内不变。该模式可以完全消除在非换相期间关断阶段出现的电流波动，并减少非换相期间的转矩波动。PWM_ON_PWM是双边调制的,但单边调制的电源开关动态损耗是相等的。六开关轮流调制，系统具有更高的可靠性。该模式运用PWMI制开启电力开关，因此即使补偿并不适用于低

32、速情况，它也可以在一定程度上抑制换相时的转矩脉动在pwm_on_pWM下，不仅可以消除非换相期间的转矩脉动，而且过低速时4Em+3rI0<Ud,通过控制换相补偿时间tc=Lln'1+仁）来控制r、rIo+2EmJ=4Em+3r|o,从而减少低速时的换相转矩脉动。高速运转时4Em+3rI0至Ud,Ud采用换相重叠保持导通相不断，通过控制换相补偿控制时间Lin1一J泉控r4-石%4E一3rle制关断相的脉冲占空比Daa=m301,从而不仅消除了非换相期间的转矩Ud脉动，也抑制了高速运转时的换相转矩脉动。用仿真对该方法进行验证，仿真参数如下：L=26mH,r=0.66Q,J=0.015

33、7kgm2,UN=48V,nN=1600j/,TL=0.4N在非全桥调制模式，如H_PWM-L_ON式，上桥臂的电源开关用PWM1式，下桥臂采用120度间隔的持续导通模式。相电流的仿真波形如图3所示，很明显非导通期间的关断相的有电流流过，且脉动频率与调制频率相同，电流幅度随调制波幅度变化，这产生了一个反转矩。412414q,OR图2HPWM-LON的相电流波形图3PWM_ON_PWM电流波形图4表示的是pwm_on_pWM的相电流波形，很明显非导通期间关断相没有电流流过，这与其他PWM1式相比，减少了非换相期间的转矩脉动。图5是占空比为0.2的无补偿PWM6制，显示了低速状态下的电流和转矩波形。图6是占空比为0.4,换相补偿时间为0.0013的PWMI制，显示了低速状态下的电流和转矩波形。通过比较可得，低速状态下，通过换相补偿，几乎可以完全消除换相导致的转矩脉动。从图3到图8可以看出，在PWM_ON_PWM下进行换相补偿控制，不仅能避免在非换相期间关断相的电流引起的转矩脉动，还可以有效的抑制在低速和高速运行下的换相转矩脉动。1图4低速运行时的相电流和转矩波