电力电子英文课件03

Chapter3ACtoDCConverters(Rectifiers)Power2Outline3.1Single-phasecontrolledrectifier3.2Three-phasecontrolledrectifier3.3Effectoftransformerleakageinductanceonrectifiercircuits3.4Capacitor-filtereduncontrolledrectifier3.5Harmonicsandpowerfactorofrectifiercircuits3.6Highpowercontrolledrectifier3.7Invertermodeoperationofrectifiercircuit3.8Realizationofphase-controlinrectifiercircuitsPower33.1Single-phasecontrolled(controllable)rectifier3.1.1Single-phasehalf-wavecontrolledrectifier3.1.2Single-phasebridgefully-controlledrectifier3.1.3Single-phasefull-wavecontrolledrectifier3.1.4Single-phasebridgehalf-controlledrectifierPower43.1.1Single-phasehalf-wavecontrolledrectifierHalf-wave,single-pulseTriggeringdelayangle,delayangle,firingangleResistiveloadTVTRu1u2uVTudida)0t12ttttu2uguduVT0b)c)d)e)002cos145.0)cos1(22)(sin221222dUUttdUU(3-1)Power53.1.1Single-phasehalf-wavecontrolledrectifierInductive(resistor-inductor)loadu20t12tttttug0ud0id0uVT0b)c)d)e)f)++a)u1TVTu2uVTudidPower6Basicthoughtprocessoftime-domainanalysisforpowerelectroniccircuitsThetime-domainbehaviorofapowerelectroniccircuitisactuallythecombinationofconsecutivetransientsofthedifferentlinearcircuitswhenthepowersemiconductordevicesareindifferentstates.a)b)VTRLVTRLu2u2tURitiLsin2dd2dd)sin(2)sin(22)(2dtZUeZUitLRωt=，id=0(3-3)(3-2)Power7Single-phasehalf-wavecontrolledrectifierwithfreewheelingdiodeMaximumforwardvoltage,maximumreversevoltageDisadvantages:–Onlysinglepulseinonelinecycle–DCcomponentinthetransformercurrentInductiveload(Lislargeenough)VTia)Tu1u2uVTLRdudVDiRVDRu2udiduVTiVTIdIdt1ttttttOOOOOO-+b)c)d)e)f)g)iVDRd2dVT2)(21ItdII(3-5)(3-6)(3-7)(3-8)2IIRdVDd221()22IIdtIRVDdd2IIdVTdPower83.1.2Single-phasebridgefully-controlledrectifierForthyristor:maximumforwardvoltage,maximumreversevoltageAdvantages:–2pulsesinonelinecycle–NoDCcomponentinthetransformercurrentResistiveloaddRTu1u2i2abVT1VT3VT2VT4udittt000i2udidb)c)d)ud(id)uVT1,4a)Power93.1.2Single-phasebridgefully-controlledrectifierResistiveloadAverageoutput(rectified)voltage(3-9)Averageoutputcurrent(3-10)Forthyristor(3-11)(3-12)Fortransformer(3-13)2cos19.02cos122)(dsin21222dUUttUU2cos19.02cos12222ddRURURUI2cos145.0212ddVTRUII2sin212)(d)sin2(21222VTRUttRUI2sin21)()sin2(12222RUtdtRUIIPower103.1.2Single-phasebridgefully-controlledrectifierCommutationThyristorvoltagesandcurrentsTransformercurrentInductiveload(Lislargeenough)TabRLa)u1u2i2VT1VT3VT2VT4udidu2OtOtOtudidi2b)OtOtuVT1,4OtOtIdIdIdIdIdiVT2,3iVT1,4cos9.0cos22)(dsin21222dUUttUU(3-15)Power11Electro-motive-force(EMF)loadDiscontinuouscurrentidWithresistora)b)REidudidOEudtIdOtPower12Electro-motive-force(EMF)loadWithresistorandinductorWhenLislargeenough,theoutputvoltageandcurrentwaveformsarethesameasordinaryinductiveload.WhenLisatacriticalvalueOud0Eidtt=dmin23dmin21087.222IUIUL(3-17)Power133.1.3Single-phasefull-wavecontrolledrectifierTransformerwithcentertapComparisonwithsingle-phasebridgefully-controlledrectifiera)b)u1TRu2u2i1VT1VT2ududi1OOttPower143.1.4Single-phasebridgehalf-controlledrectifierHalf-controlComparisonwithfully-controlledrectifierAdditionalfreewheelingdiodeOb)u2OudidIdOOOOOi2IdIdIdIdIdtttttttiVT1iVD4iVT2iVD3iVDRabRLu2i2udidVT1VT2VD3VD4VDRTPower15Anothersingle-phasebridgehalf-controlledrectifierComparisonwithpreviouscircuit:–Noneedforadditionalfreewheelingdiode–IsolationisnecessarybetweenthedrivecircuitsofthetwothyristorsTu2VD3VD4VT1VT2loadPower16SummaryofsomeimportantpointsinanalysisWhenanalyzingathyristorcircuit,startfromadiodecircuitwiththesametopology.Thebehaviorofthediodecircuitisexactlythesameasthethyristorcircuitwhenfiringangleis0.Apowerelectroniccircuitcanbeconsideredasdifferentlinearcircuitswhenthepowersemiconductordevicesareindifferentstates.Thetime-domainbehaviorofthepowerelectroniccircuitisactuallythecombinationofconsecutivetransientsofthedifferentlinearcircuits.Takedifferentprinciplewhendealingwithdifferentload–Forresistiveload:currentwaveformofaresistoristhesameasthevoltagewaveform–Forinductiveloadwithalargeinductor:theinductorcurrentcanbeconsideredconstantPower173.2Three-phasecontrolled(controllable)rectifier3.2.1Three-phasehalf-wavecontrolledrectifier(thebasiccircuitamongthree-phaserectifiers)3.2.2Three-phasebridgefully-controlledrectifier(themostwidelyusedcircuitamongthree-phaserectifiers)Power183.2.1Three-phasehalf-wavecontrolledrectifierCommon-cathodeconnectionNaturalcommutationpointResistiveload,=0ºTRudidVT2VT1VT3u2uaubucOt1t2t3uGOudOOuabuacOiVT1uVT1tttttPower19Resistiveload,=30ºTRudidVT2VT1VT3u2uaubucOtOtOtOtOtuGuduabuact1iVT1uVT1uacPower20Resistiveload,=60ºTRudidVT2VT1VT3ttttu2uaubucOOOOuGudiVT1Power21Resistiveload,quantitativeanalysisWhen30º,loadcurrentidiscontinuous.When30º,loadcurrentidisdiscontinuous.cos17.1cos263)(sin2321226562dUUttdUU)6cos(167