PSIM-使用教学(new).ppt

PSIM使用教學,Contents,SetupPSIM6.0IntroductionbasicfunctionsExample-BuckconverterHomework,1.SetupPSIM6.0,OpeningThePSIM6.0File,Clickingthe.exe,SetupSteps,2.Introductionbasicfunctions,OpenANewFile,Newworkspace,MainWorkingFunctions,常用元件,Runsimulation,觀看波形圖,SelectingElements,所有元件,PlacingElements,1.點選元件後在電路圖中連續點左鍵即可連續放置相同元件，如要取消則按Esc2.在未放下元件前點選滑鼠右鍵則可以將元件旋轉90度,PlacingElements(Cont.),鏡射、翻轉,拉線,注意:點各元件左鍵兩下可以修改各元件值，其中Currentflag的值設為1的話，即可在模擬後查看元件通過的電流大小。,3.Example-BuckConverter,Buckconverter,L,C,Diode,+,-,+,-,vL,on-offswitchcontroller,mosfet,量測電壓電流波形,voltageandcurrentprobe,差動電壓探棒,runsimulation或按F8,waveforms,waveform(cont.),Addscreen,addscreen(增加視窗看波形),waveform(cont.),Add/deletecurve,Add/deletecurve(可在同一視窗看多個波形),waveform(cont.),zoom,waveform(cont.),Measure,measure,顯示measure值視窗,4.Homework,Homework,V1,V2,1.利用psim模擬電路(1)，並在波形中顯示V1,V2,I1,I2的值，最後與自己計算的結果相比較。,(1),(2),2.開關在t=0之前，已關閉很長一段時間，在t=0時打開，試用psim模擬t0之後的Vo波形，並計算出電容在t=0時的初始值與模擬相比較。,Vi,Vo,如何在psim模擬左側電路的頻率響應圖?,R,C,R=1k,C=0.1uF,poleat10krad/s=1.59kHz,頻率響應,頻率響應,頻率響應,flagforpoints=0log10scale,flagforpoints=1linearscale,頻率響應,頻率響應,a.設定timestep為掃到最終頻率週期的0.01倍,b.Totaltime使得系統進入穩態,bodeplot,-3dBpoint,buckconverter,如何去跑duty對Vo的頻率響應?,polesat-2000+4000i-2000-4000i4472rad/s711Hz,頻率響應,startamplitude為dc值的0.01倍endamplitude增大5倍,頻率響應,b.totaltime0.01秒使系統進入穩態,a.設定timestep為掃到最終頻率週期的0.01倍,bodeplot,711Hz,dcgain=20log50=34,2.BuildingaSubcircuit,Whyweneedtobuildsubcircuit?,Controllercircuit,PowerStage,Step1GeneratingaNewSubcircuit,NewSubcircuit對此方塊點左鍵兩下進行內部電路編輯,Step2Editingthesubcircuit,子方塊內部架構編輯視窗,將此部份電路丟到子方塊內部,Step2EditingTheSubcircuit(Cont.),Step3EditingPortName,PortPlace,Step4ChangingTheSubcircuitSize,Step5FinishingTheSubcircuit,Step6ChangingTheText,TextColor,Changingwordsize,BuckConverterPresentationDigitalDisplayandMediaPowerNCPowerSBULITE-ONTechnologyCorp.MHCHANJune,24th,2007,1.BuckConverterPrincipleandDesign,Outline,1.Principle2.Continuous-ConductionMode(CCM)3.BoundaryMode4.Discontinuous-ConductionMode(DCM)5.Simulation,Principle-Basic,ThisisabasicDC-DCconverter.Averageoutputvoltage:,Principle-Buck,1.Inductoractingasshortcircuitinsteadystate.2.Capacitorsactasopencircuitinsteadystate.3.Thecurrentflowsoninductoriscontinuous.4.BuckconverterisanDC-DCconverter.Anditsoutputvoltageisalwayssmallerthaninputvoltage.,Principle-Switchfrequency,Fromleftpicture,switchhasitsharmonicdistortion.Howcanreducetheinfluenceofoutputvoltageswing?,Switchfrequencyismuchlargerthanthecornerfrequency.Eliminatetheharmonicdistortionofswitching.,CCM-Capacitorsvoltagecontinue,Whenswitchison,VLispositiveandequalto(VdVo).Whenswitchisoff,thecapacitorsvoltageismaintainVo.SoVLturnstonegativeandequalto(Vo).,tontoff,CCM-Inductorsshortfeature,Theinductorsaveragevoltagewillequaltozero.,CCM-Inductorscurrentcontinue,Thecurrentflowsontheinductorisstillthesamedirectionevenwhentheswitchturnsoff.Theinductorabsorbsenergywhenswitchison.Andreleasingpowerwhenswitchturnsoff.,CCM-Calculatethepeakinductorcurrent,ILpeak,Theslopeformulaofinductorcurrentisshownbelow:,Thepeakvalueoftheinductorcurrentis:,BoundaryMode,Whenouraverageoutputcurrentreduces,iL,minmaybetouchthebottomofzerocurrent.,WecanselecttonortofftocalculatetheILBandIOB.Weusetontocalculatebelow:,BoundaryMode-Themaxvalue,Weknow:,Itsafunctionofdutycycle,Ifwewanttofinditsmaximumvalue.Wecanderivatethefunctionbydutycycle:,CCM-Outputvoltageripple,AssumealloftheripplecomponentiniLflowsthroughthecapacitoranditsaveragecomponentflowsthroughload.Theadditioncharge,Q,representthechangeofthecapacitor.,From:,Wecanfindout:,DCM-Discussion1,Inductorsaveragevoltageisstillzeroinsteadystate.,DCM-Discussion2,ThenwecangetthevalueofiLpeak:,Finally,wecanfindthevalueofIo:,Step-DownDC-DCConverter:LimitsofCont./Discont.Conduction,CCM,DCM,BCM,(a),(b),(c),combine(a)and(b),wecanplot(c),Example,T,+,-,Vin,vao,+,-,iL,L,vL,+,-,vo,+,-,io,C,low-passfilter,iQ,ico,id,Cin,ici,Q,D,PWMWaveformGenerator,iin,DC/DCConverter,inputvoltageVin=10VoutputvoltageVout=5Vswitchingfrequencyfs=100kHzloadresistanceR=10,R,1.ChoosethevalueofLsuchthat,2.ChoosethevalueofCsuchthat,Continuousmodecondition(CCM),0.05V,0.05A,BoundaryModeCondition(BCM),DiscountinuousmodeCondition(DCM),5us,3.754us,DiscountinuousmodeCondition(DCM),5.7V,DiscountinuousmodeCondition(DCM),18.97mA,2.BoostConverterPrincipleandDesign,Principle,1.Capacitorsvoltageiscontinuous.2.Inductorscurrentiscontinuous.3.ItsaDC-DCconverter.Outputvoltageishigherthaninputvoltage.(Step-up),CCMUsePrinciples,GreenArea=YellowArea,CCMInductorsCurrentRipple,From:,OutputVoltage,From:,Q=YellowArea:,PS:Assumingalltheripplecurrentcomponentofdiodecurrentflowsthroughcapacitor.(Meaningoutputvoltageisconstant.),CCMInputandOutputCurrent,BuckConverter:,IL,avg=Io,avg,BoostConverter:,Assumelossless.VdId=VoIo,BoundaryModeILBandLOB,Firstofall:,Then,Io=IL(1-D):,BoundaryModeMaxValue,Forthemaxvalue,usingdifferential:,EffectOfParasiticElements,D=1meansVo=infinity?,1.Poorswitchutilizationathighvaluesofdutyratio.2.TheeffectofESRininductor.,CalculateByHand:,EX:AboostconverteruseinPFCdesigncircuitwith346.5W.Inputvoltageis156V.Outputvoltageis385Vandcurrentis0.9A.Andtheswitchfrequencyis100KHZ.Nowwewantoutputvoltagerippleisbelow5%andinductorcurrentripplebelow10%.Calculatethevalueofcapacitorandinductor.,CalculateByHand-Continue,DesignGuide-Switch,1.Maxcrossvoltage:(Atswitchopen.),Vds,max=Vo=385(V)3851.25=481.25(V),2.Maxflowthroughcurrent:(Atswitchon.),ID,max=IL,peak=6.66(A)6.661.25=8.325(A),DesignGuide-Diode,1.Maxcrossvoltage:(Atswitchon.),VD,max=Vo=385(V)3851.25=481.25(V),2.Maxflowthroughcurrent:(Atswitchopen.),ID,max=IL,peak=6.66(A)6.661.25=8.325(A),ParasiticCapacitorAnalysis,ImpedanceofaRealDecouplingCapacitor,阻抗推導,Pole:,zero:,ParasiticsandImpedanceofa“Real”Capacitor,as,Mag=|Rs+|,BodePlotwithMatlab,Rp=1kRp=100kRp=,1,2,3,3,2,1,SimulationwithPSIM,為了減少模擬的時間，做了參數上的部份修正！,SimulationWave,SimulationWave(Cont),TimeDomainSimulation,SwitchingConverterSmall-signalModeling,Controltoregulateoutputvoltage,feedbackcontrolsystem,linearizedfeedbackcontrolsystem,Content,LinearizationofthePowerStageIncludingtheOutputFilterUsingState-SpaceAveragetoObtainTp(s)TransferFunctionoftheDirectDutyRatioPulse-WidthModulatorTm(s)Tp(s)forBuckConverteratCCMMode,State-SpaceAveragingMethod-CCM&Constantswitchingfrequency,Step1.State-VariableDescriptionforEachCircuitState,duringdTs,during(1-d)Ts,Step2.AveragingtheState-VariableDescriptionUsingtheDutyRatiod,Theonandoffstatearetimeweightedandaveraged,whereA1andA2arestatemaricesandB1andB2arevectors,State-SpaceAveragingMethod-CCM&Constantswitchingfrequency,Step3.IntroducingSmallacPerturbationsandSeparationintoacanddcComponents,assume,State-SpaceAveragingMethod-CCM&Constantswitchingfrequency,Atsteadystate,alltheacperturbationsandtheirderivativesarezero,isthedcvoltagetransferfunction,Step4.TransformationoftheacEquationsintos-DomaintoSolvefortheTrans