PWM整流器外文翻譯

1、ACVoltageandCurrentSensorlessControlofThree-PhasePWMRectifiersDong-ChoonLee,Member,IEEE,andDae-SikLim1THREE-PHASEPWMRECTIFIERSASystemModelingFig.1showsthepowercircuitofthethree-phasePWMrectifier.Thevoltageequationsaregivenbywhere,andarethesourcevoltage,thelinecurrent,andtherectifierinputvoltage,resp

2、ectivelyandaretheinputresistanceandtheinputinductance,respectively.Whenthepeaklinevoltage,angularfrequency,andinitialphaseanglearegiven,assumingabalancedthree-phasesystem,thesourcephasevoltageisexpressedascosEcos(cos(Where(3)Atransformationmatrixbasedontheestimatedphasea ngle,whichtransformsthree-ph

3、asevariablesintoasynchronousdpreferenceframe,iseaRpL00ebecRpL00RpLVaVbVc(1)eaebeccFig.1.Three-phasePWMrectifierwithoutac-sidesensors.cos(M3)cos(M23)sin(M2)sin(M3)Transforming(1)intothereferenceframeusing(4)eqcRpLMLiqcvqcedcMLRPLidcVdcwherepisadifferentialoperatorand.MExpressing(5)inavectornotationeR

4、iMLJipLivwhere,eqc.iqcvqcei.vJedcidcvdcTakingatransformationof(2)byusing(4)EcoseEsinWhereMExpressing(6)and(8)inadiscretedomain,byapproximatingthederivativetermin(6)byaforwarddifference9,respectively,e(k1)Ri(k1)MLJi(k1)WhereTisthesamplingperiod.cosM23sinM(4)(5)(6)(7)(8)(9)：i(k)i(k1)v(k1)e(k1)Ecos(k1)

5、Esin(k1)(10)(11)BSystemControlThePIcontrollersareusedtoregulatethedcoutputvoltageandtheacinputcurrent.Fordecouplingcurrentcontrol,thecross-couplingtermsarecompensatedinafeedforward-typeandthesourcevoltageisalsocompensatedasadisturbance.Fortransientresponseswithoutovershoot,theanti-winduptechniqueise

6、mployed10.TheoverallcontrolblockdiagrameliminatingthesourcevoltageandlinecurrentsensorsisshowninFig.2.Theestimationalgorithmofsourcevoltagesandlinecurrentsisdescribedinthefollowingsections.2PREDICTIVECURRENTESTIMATIONThecurrentsofIa(k)andIc(k)cannotbecalculatedinstantlysincethecalculationtimeoftheDS

7、Pisrequired.Toeliminatethedelayeffect,astateobservercaneffectsfortheestimatedvariable.Expressing(5)inastate-spaceform,where,01iqceqcvqcxuidcedcvdcAndyistheoutput.Transforming(12)and(13)intoadiscretedomain,respectively,beused.Inaddition,thestateobserverprovidesthefilteringAxBuCx(12)(13)Fig.2.Overallc

8、ontrolblockdiagram.X(k1)FX(k)GU(k)(14)Y(k)HX(k)(15)where,RT1RT1TT0FLGL1T1RT0TLL,Then,theobserverequationaddinganerrorcorrectiontermtoisgivenbyX(k1)FX(k)GU(k)K(Y(k)Y(k)(16)WhereKistheobservergainmatrixand伙meanstheestimatedquantity,andX(k1)isthestatevariableestimatedaheadonesamplingperiod.Subtracting(

9、15)from(16),theerrordynamicequationoftheobserverisexpressedaserr(k1)FKCerr(k)(17)whereerr(k)X(k)X(k).Here,itisassumedthatthemodelparametersmatchwellwiththerealones.Fig.3showstheblockdiagramoftheclosed-loopstateobserver.Thestatevariableerrordependsonlyontheinitialerrorandisindependentoftheinput.For(1

10、7)toconvergetothezerostate,therootsofthecharacteristicequationQf17)shouldbelocatedwithintheunitcircle.Fig.3.Closed-loopstateobserver.3EXPERIMENTSANDDISCUSSIONSA.SystemHardwareConfigurationIsolationAmplifierSpaceVccliirPWMA/DConverfcrFig.5.Systemhardwareconfiguration.HOSTcojnputfrcojnputfrCJCJJ JU(DS

11、PTMS32OC31)U(DSPTMS32OC31)ZR5C3OIHAHAaonaonFig.4.Shortpulseregion.Fig.5showsthesystemhardwareconfiguration.Thesourcevoltageisathree-phase,110V.Theinputresistanceandinductanceare0.06Qand3.3mH,respectively.Thedclinkcapacitanceis2350仙FandtheswitchingfrequencyofthePWMrectifieris3.5kHz.A+A+公身A-A-Optical1

12、iberTheTMS320C31DSPchipoperatingat33.3MHzisusedasamainprocessorandtwo12-bA/Dconvertersareused.Oneofthemisdedicatedfordetectingthedclinkcurrentandtheotherisusedformeasuringthedcoutputvoltageandthesourcevoltagesandcurrents,whereacsidequantitiesarejustmeasuredforperformancecomparison.Oneoftwointernalti

13、mersintheDSPisemployedtodecidethePWMcontrolperiodandtheotherisusedtodeterminethedclinkcurrentinterrupt.Consideringtherectifierblankingtimeof3.5s,A/Dconversiontimeof2.6s,andtheothersignaldelaytime,theminimumpulsewidthissetto10s.A.ExperimentalResultsFig.6showsmeasureddclinkcurrentsandphasecurrents.Inc

14、aseofsectorVofthespacevectordiagram,thedclinkcurrentcorrespondstofortheswitchingstateofandforthatof.Fig.7(a)showstherawdclinkcurrentbeforefiltering.Ithasalotofringingcomponentsduetotheresonanceoftheleakageinductanceandthesnubbercapacitor.Whenthedccurrentissampledattheendpointoftheactivevoltagevector

15、sasshowninthefigure,themeasuringerrorcanbereduced.(b)Fig.6.Dclinkcurrentsandcorrespondingphasecurrents(insectorV).Toreducethiserrorfurther,thelowpassfiltershouldbeemployed,ofwhichresultisshowninFig.7(b).Thecut-offfrequencyoftheButterworthkHzanditsdelaytimeisabout2sec.Sincetheringingfrequencyis258kHz

16、andtheswitchingfrequencyis3.5kHz,thefilteredsignalwithoutsignificantdelayisacquired.Fig.8showstheestimatedsourcevoltageandcurrentatstarting.Withtheproposedinitialestimationstrategy,thestartingoperationiswellperformed.Fig.9showsthephaseangle,magnitude,andwaveformoftheestimatedsourcevoltage,whichcoinc

17、idewellwithmeasuredones.Fig.10showsthesourcevoltageandcurrentwaveformatunitypowerfactor.Figs.Withtheestimatedquantitiesforthefeedbackcontrol,thecontrolperformanceissatisfactory.Thedcvoltagevariationforloadchangeswillberemarkablydecreasedifafeedforwardcontrolfortheloadcurrentisadded,whichispossiblewi

18、thoutadditionalcur-rentsensorwhenthePWMrectifieriscombinedwiththePWMinverterforacmotorssecdedfilteris112Fig.8.Estimatedsourcevoltageandcurrentatstarting.drives.Fig.9.Estimatedsourcevoltageinsteadystate.(a)phaseangle(b)magnitude(c)waveform.Fig.10.Sourcevoltageandcurrentwaveforms.(a)estimated(b)measur

19、ed.4CONCLUSIONSThispaperproposedanovelcontrolschemeofthePWMrectifierswithoutemployinganyacinputvoltageandcurrentsensorsandwithusingdcvoltageandcurrentsensorsonly.Reducingthenumberofthesensorsuseddecreasesthesystemcostaswellasimprovesthesystemreliability.Thephaseangleandthemagnitudeofthesourcevoltage

20、havebeenestimatedbycontrollingthedeviationbetweentherectifiercurrentanditsmodelcurrenttobezero.Forlinecurrentreconstruction,switchingstatesandmeasureddclinkcurrentswereused.Toeliminatetheeffectofthecalculationtimedelayofthemicroprocessor,thepredictivestateobserverwasused.Itwasshownthattheestimationa

21、lgorithmisrobusttotheparametervariation.Thewholealgorithmhasbeenimplementedforaproto-type1.5kVAPWMrectifiersystemcontrolledbyTMS320C31DSP.Theexperimentalresultshaveverifiedthattheproposedacsensoreliminationmethodisfeasible.無交流電壓、電流傳感器的三相PWM整流器控制Dong-ChoonLee,Member,IEEE,andDae-SikLim1三相PWM整流器A系統(tǒng)模型圖一

22、所示為三相PWM整流器的主電路，電壓等式給出如下:圖1無交流傳感器三相PWM整流器其中e,i和v分別是源電壓，線電流和整流器的輸入電壓，R和L分別是輸入電阻和輸入電感。當已知線電壓峰值E,角頻率和初始相位角8時，假定三相系統(tǒng)是平衡的，則源相位電壓可以表達為cosea2、ebEcos(-)3ec2cos(一)3其中(3)一種基于估計相位角m的變換矩陣，將三相變量變換成一個同步的,系，這個矩陣是eaRPLebec00RpL00RpLVaVbVc(1)dq坐標將（1）式變?yōu)閐q坐標系使用式（4）cosM2cos(M2)cos(M23)3sinMsin(M2)sin(M3)(4)eqcedc其中P是一

23、個微分算子且M將（5）式寫成矢量形式eRi其中ec.iqceiedcidc,用式（4）對（2）式進行變換RpLMLiqcVqcMLRpLidcVdcMMLJipLivVqc01VJVdc10EcoseEsin其中(5)(6)(7)(8)(9)通過前向差分來接近微分的限幅，分別將（6）式和（8）式用離散域表小e(k1)Ri(k1)MLJi(k1)Li(k)i(k1)v(k1)e(k1)Ecos(k1)Esin(k1)(10)(11)其中，T是采樣周期CtrntrailerCtrntrailerv vRcclilwrrRcclilwrrStniieOhsmtr1StniieOhsmtr1Sourc

24、ecurFcneailniRl.lSourcecurFcneailniRl.lQnQnCtlEHlCtlEHlCnDimllerCnDimllerCurrc-nlRwnvCurrc-nlRwnvi i孤ruerue為 n圖2總的控制模塊圖CiirrtiltCiirrtiltCanlretltrCanlretltrmirkriMk-biuretvolumeaitmaclonbiuretvolumeaitmaclonX(k1)FX(k)GU(k)K(Y(k)砥k)(16)B系統(tǒng)控制PI控制器是用來調(diào)節(jié)直流輸出電壓和交流輸入電流的。對于解耦電流控制，交叉耦合項用前饋式補償，同時，源電壓作為擾動的補償

25、。對于沒有過調(diào)的暫態(tài)響應，引入anti-windup技術(shù)。消除源電壓和線電流傳感器的總的控制模塊圖如圖2所示。源電壓和線電流的估計算法在以后的章節(jié)中介紹。2預測電流估計由于DSP存在計算時間，所以Ia（k）和Ic（k）不能立即計算。為了消除延遲的影響,可以使用狀態(tài)監(jiān)測器。另外，狀態(tài)監(jiān)測器可以對估計變量起到濾波作用將式（5）用狀態(tài)空間形式表達為(12)(13)其中Y是輸出分別將式（12）和式（13）分別變換成離散領(lǐng)域其中RTRT則加入了誤差調(diào)整的監(jiān)測器等式為其中，k是監(jiān)測器增益矩陣，“人”是指估計量，X（k1）是提前一個采樣周期估計的狀AxBuCxiqcideqcvqcedcvdcX(k1)FX

26、(k)GU(k)Y(k)HX(k)(14)(15)態(tài)變量。用式（15）和減去式（16）,監(jiān)測器的動態(tài)誤差等式表述為0.（k1）FKC6r.（k）（17）其中（k）X（k）X（k）這里，假設模型參數(shù)與真實系統(tǒng)吻合的很好。圖7所示是閉環(huán)狀態(tài)監(jiān)測器的模塊圖。狀態(tài)變量誤差僅取決于初始誤差，與輸入無關(guān)。為了使式（17）趨于零狀態(tài)，典型等式（17）的根應該限制在單位圓內(nèi)。圖3閉環(huán)狀態(tài)監(jiān)測器圖4短脈沖區(qū)域3實驗與討論A系統(tǒng)硬件構(gòu)造SpaceVectorPMMVectorPMMAUCmvurtcrAUCmvurtcr圖5系統(tǒng)硬件結(jié)構(gòu)圖6直流電流和相應相電流（扇區(qū)5）.圖5所示是系統(tǒng)的硬件結(jié)構(gòu)圖。源電壓是三相110V。輸入電阻和電感分別為0.06陰口3.3mH0直流側(cè)電容為2350心PWM整流器的開關(guān)切換頻率為3.5KHZ.使用TMS320C31DSP芯片設定在33.3MHZ作為主處理器，同時用到兩個12位的A/D轉(zhuǎn)換器：一個用來檢測直流側(cè)電流，另一個用來檢測直流側(cè)輸出電壓、源電壓和電流。其中直流側(cè)數(shù)量只是為了性能比較而測量的。DSP內(nèi)部的兩個時鐘一個是用來決定PWM波的控制周期，另一個是用來決定直流側(cè)電流中斷。考慮到整流器空白時間3.5心A/D轉(zhuǎn)換時間2.6小酥口其他信號延遲時間，最小脈沖寬度Tmin設定為10pSHoticomputerHoticomputerC