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PowerElectronicsPowerElectronicsChapter3ACtoDCConverters(Rectifiers)PowerElectronics2OutlineOutline3.1Single3.1Single--phasecontrolledrectifierphasecontrolledrectifier3.2Three3.2Three--phasecontrolledrectifierphasecontrolledrectifier3.3Effectoftransformerleakageinductanceon3.3Effectoftransformerleakageinductanceonrectifiercircuitsrectifiercircuits3.4Capacitor3.4Capacitor--filtereduncontrolledrectifierfiltereduncontrolledrectifier3.5Harmonicsandpowerfactorofrectifiercircuits3.5Harmonicsandpowerfactorofrectifiercircuits3.6Highpowercontrolledrectifier3.6Highpowercontrolledrectifier3.7Invertermodeoperationofrectifiercircuit3.7Invertermodeoperationofrectifiercircuit3.8Realizationofphase3.8Realizationofphase--controlinrectifiercircuitscontrolinrectifiercircuitsPowerElectronics33.1Single3.1Single--phasecontrolledphasecontrolled(controllable)rectifier(controllable)rectifier3.1.1Single3.1.1Single--phasehalfphasehalf--wavecontrolledrectifierwavecontrolledrectifier3.1.2Single3.1.2Single--phasebridgefullyphasebridgefully--controlledrectifiercontrolledrectifier3.1.3Single3.1.3Single--phasefullphasefull--wavecontrolledrectifierwavecontrolledrectifier3.1.4Single3.1.4Single--phasebridgehalfphasebridgehalf--controlledrectifiercontrolledrectifierPowerElectronics43.1.1Single3.1.1Single--phasehalfphasehalf--wavewavecontrolledrectifiercontrolledrectifierHalfHalf--wave,singlewave,single--pulsepulseTriggeringdelayangle,delayangle,firingangleTriggeringdelayangle,delayangle,firingangleResistiveloadResistiveloadTVTRu1u2uVTudida)0wt1π2πwtwtwtwtu2uguduVTaq0b)c)d)e)00∫+=+==paaapwwp2cos145.0)cos1(22)(sin221222dUUttdUU(3-1)PowerElectronics53.1.1Single3.1.1Single--phasehalfphasehalf--wavewavecontrolledrectifiercontrolledrectifierInductive(resistorInductive(resistor--inductor)loadinductor)loadu20wt1π2πwtwtwtwtwtug0ud0id0uVT0qab)c)d)e)f)++a)u1TVTu2uVTudidPowerElectronics6BasicthoughtprocessoftimeBasicthoughtprocessoftime--domaindomainanalysisforpowerelectroniccircuitsanalysisforpowerelectroniccircuitsThetimeThetime--domainbehaviorofapowerelectronicdomainbehaviorofapowerelectroniccircuitisactuallythecombinationofconsecutivecircuitisactuallythecombinationofconsecutivetransientsofthedifferentlinearcircuitswhenthetransientsofthedifferentlinearcircuitswhenthepowersemiconductordevicesareindifferentstates.powersemiconductordevicesareindifferentstates.a)b)VTRLVTRLu2u2tURitiLwsin2dd2dd=+)sin(2)sin(22)(2djwjaaww-+--=--tZUeZUitLRωt=a，id=0(3-3)(3-2)PowerElectronics7SingleSingle--phasehalfphasehalf--wavecontrolledwavecontrolledrectifierwithfreewheelingdioderectifierwithfreewheelingdiodeMaximumforwardvoltage,maximumreversevoltageMaximumforwardvoltage,maximumreversevoltageDisadvantages:Disadvantages:––OnlysinglepulseinonelinecycleOnlysinglepulseinonelinecycle––DCcomponentinthetransformercurrentDCcomponentinthetransformercurrentInductiveload(Lislargeenough)Inductiveload(Lislargeenough)VTia)Tu1u2uVTLRdudVDiRVDRu2udiduVTiVTIdIdwt1wtwtwtwtwtwtOOOOOOπ-aπ+ab)c)d)e)f)g)iVDRd2dVT2)(21ItdIIpapwppa-==∫(3-5)(3-6)(3-7)(3-8)2IIpap+=RdVDd221()22IIdtIpappawpp++==∫RVDdd2IIpap-=dVTdPowerElectronics83.1.2Single3.1.2Single--phasebridgephasebridgefullyfully--controlledrectifiercontrolledrectifierForthyristor:maximumforwardvoltage,maximumForthyristor:maximumforwardvoltage,maximumreversevoltagereversevoltageAdvantages:Advantages:––2pulsesinonelinecycle2pulsesinonelinecycle––NoDCcomponentinthetransformercurrentNoDCcomponentinthetransformercurrentResistiveloadResistiveloaddRTu1u2i2abVT1VT3VT2VT4udiπwtwtwt000i2udidb)c)d)ud(id)aauVT1,4a)PowerElectronics93.1.2Single3.1.2Single--phasebridgefullyphasebridgefully--controlledrectifiercontrolledrectifierResistiveloadResistiveloadAverageoutput(rectified)voltageAverageoutput(rectified)voltage(3(3--9)9)AverageoutputcurrentAverageoutputcurrent(3(3--10)10)ForthyristorForthyristor(3(3--11)11)(3(3--12)12)FortransformerFortransformer(3(3--13)13)∫+=+==paaapwwp2cos19.02cos122)(dsin21222dUUttUU2cos19.02cos12222ddaap+=+==RURURUI2cos145.0212ddVTa+==RUIIpapapwwppa-+==∫2sin212)(d)sin2(21222VTRUttRUIpapapwwppa-+===∫2sin21)()sin2(12222RUtdtRUIIPowerElectronics103.1.2Single3.1.2Single--phasebridgephasebridgefullyfully--controlledrectifiercontrolledrectifierCommutationCommutationThyristorvoltagesandcurrentsThyristorvoltagesandcurrentsTransformercurrentTransformercurrentInductiveloadInductiveload(Lislargeenough)(Lislargeenough)TabRLa)u1u2i2VT1VT3VT2VT4udidu2OwtOwtOwtudidi2b)OwtOwtuVT1,4OwtOwtIdIdIdIdIdiVT2,3iVT1,4∫+===apaaapwwpcos9.0cos22)(dsin21222dUUttUU(3-15)PowerElectronics11ElectroElectro--motivemotive--force(EMF)loadforce(EMF)loadDiscontinuouscurrentiDiscontinuouscurrentiddWithresistorWithresistora)b)REidudidOEudwtIdOwtaqdPowerElectronics12ElectroElectro--motivemotive--force(EMF)loadforce(EMF)loadWithresistorandinductorWithresistorandinductorWhenLislargeenough,theoutputvoltageandWhenLislargeenough,theoutputvoltageandcurrentwaveformsarethesameasordinarycurrentwaveformsarethesameasordinaryinductiveload.inductiveload.WhenLisatacriticalvalueWhenLisatacri