PSIM 使用教学(new)讲课教案.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 0 log10scale flagforpoints 1 linearscale 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 4000i 4472rad s 711Hz 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 Andit soutputvoltageisalwayssmallerthaninputvoltage Principle Switchfrequency Fromleftpicture switchhasits harmonicdistortion Howcanreducetheinfluenceofoutputvoltageswing Switchfrequencyismuchlargerthanthecornerfrequency Eliminatetheharmonicdistortionofswitching CCM Capacitor svoltagecontinue Whenswitchison VLispositiveandequalto Vd Vo Whenswitchisoff thecapacitor svoltageismaintainVo SoVLturnstonegativeandequalto Vo tontoff CCM Inductor sshortfeature Theinductor saveragevoltagewillequaltozero CCM Inductor scurrentcontinue Thecurrentflowsontheinductorisstillthesamedirectionevenwhentheswitchturnsoff Theinductorabsorbsenergywhenswitchison Andreleasingpowerwhenswitchturnsoff CCM Calculatethepeakinductorcurrent ILpeak Theslopeformulaofinductorcurrentisshownbelow Thepeakvalueoftheinductorcurrentis BoundaryMode Whenouraverageoutputcurrentreduces iL minmaybetouchthebottomofzerocurrent WecanselecttonortofftocalculatetheILBandIOB Weusetontocalculatebelow BoundaryMode Themaxvalue Weknow It safunctionofdutycycle Ifwewanttofindits maximumvalue Wecanderivatethefunctionbydutycycle CCM Outputvoltageripple AssumealloftheripplecomponentiniLflowsthroughthecapacitoranditsaveragecomponentflowsthroughload Theadditioncharge Q representthechangeofthecapacitor From Wecanfindout DCM Discussion1 Inductor saveragevoltageisstillzeroinsteadystate 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 Capacitor svoltageiscontinuous 2 Inductor scurrentiscontinuous 3 It saDC DCconverter Outputvoltageishigherthaninputvoltage Step up CCM UsePrinciples GreenArea YellowArea CCM Inductor sCurrentRipple From OutputVoltage From Q YellowArea PS Assumingalltheripplecurrentcomponentofdiodecurrentflowsthroughcapacitor Meaningoutputvoltageisconstant CCM InputandOutputCurrent BuckConverter IL avg Io avg BoostConverter Assumelossless Vd Id Vo Io BoundaryMode ILBandLOB Firstofall Then Io IL 1 D BoundaryMode MaxValue 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 385 1 25 481 25 V 2 Maxflowthroughcurrent Atswitchon ID max IL peak 6 66 A 6 66 1 25 8 325 A DesignGuide Diode 1 Maxcrossvoltage Atswitchon VD max Vo 385 V 385 1 25 481 25 V 2 Maxflowthroughcurrent Atswitchopen ID max IL peak 6 66 A 6 66 1 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 Con t TimeDomainSimulation SwitchingConverterSmall signalModeling Controltoregulateoutputvoltage feedbackcontrolsystem linearizedfeedbackcontrolsystem Content LinearizationofthePowerStageIncludingtheOutputFilterUsingState SpaceAveragetoObtainTp s TransferFunctionoftheDirectDutyRatioPulse WidthModulatorTm s Tp s forBuckConverteratCCMMode State SpaceAveragingMethod CCM Constantswitchingfrequency Step1 State VariableDescriptionforEachCircuitState duringd Ts 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 DomaintoSolvefortheTransferFunction andareacequatio