5.6 多重逆變電路和多電平逆變電路 Multiple inverter circuits and multilevel inverter circuits中英版

Multipleinvertercircuitsandmulti-levelinvertercircuits5.6多重逆變電路和多電平逆變電路TeachingResourcesDatabaseof

NationalVocationalEducationPowerSupplyTechnologyBilingualcourses.Powerelectronicstechnology電力電子技術(shù)Item5InverterCircuit項(xiàng)目五逆變電路多重逆變電路把幾個(gè)矩形波組合起來(lái)，接近正弦。多電平逆變電路輸出較多電平，使輸出接近正弦。Multipleinvertercircuitsandmulti-levelinvertercircuits5.6多重逆變電路和多電平逆變電路Multipleinvertercircuitcombineseveralrectangularwaves,approximatingsinusoidal.Themulti-levelinvertercircuitoutputsmorelevels,makingtheoutputclosetosine.多重逆變電路MultipleinvertercircuitMultipleinvertercircuitsandmulti-levelinvertercircuits5.6多重逆變電路和多電平逆變電路電壓型、電流型都可多重化，以電壓型為例。Bothvoltageandcurrentpatternscanbemultiplicated.Takevoltagepatternsasanexample.單相電壓型二重逆變電路

Single-phasevoltagetypedualinvertercircuit兩個(gè)單相全橋逆變電路組成，輸出通過(guò)變壓器T1和T2串聯(lián)起來(lái)。Itconsistsoftwosingle-phasefull-bridgeinvertercircuits,theoutputisconnectedinseriesthroughtransformersT1andT2.輸出波形：兩個(gè)單相的輸出u1和u2是180°矩形波。OutputWaveforms:Thetwosingle-phaseoutputsU1andU2are180°rectangularwaves.圖2二重逆變電路的工作波形Fig.2Workingwaveformofdualinvertercircuit120°60°180°tOtOtO三次諧波三次諧波u1u2uo圖1二重單相逆變電路Fig.1Dualsingle-phaseinvertercircuitThirdHarmonic多重逆變電路有串聯(lián)多重和并聯(lián)多重兩種Therearetwokindsofmultipleinvertercircuits:seriesmultipleandparallelmultiple串聯(lián)多重——把幾個(gè)逆變電路的輸出串聯(lián)起來(lái)，多用于電壓型。Seriesmultiple-theoutputofseveralinvertercircuitstogetherinseries,mostlyforvoltagetype.并聯(lián)多重——把幾個(gè)逆變電路的輸出并聯(lián)起來(lái)，多用于電流型。ParallelMultiplication-Toconnecttheoutputsofseveralinvertercircuitsinparallel,mostlyforcurrentapplications.Multipleinvertercircuitsandmulti-levelinvertercircuits5.6多重逆變電路和多電平逆變電路圖2二重逆變電路的工作波形Fig.2Workingwaveformofdualinvertercircuit120°60°180°tOtOtO三次諧波三次諧波u1u2uo圖1二重單相逆變電路Fig.1Dualsingle-phaseinvertercircuitThirdHarmonicu1和u2相位錯(cuò)開(kāi)j=60°,其中的3次諧波就錯(cuò)開(kāi)了3×60°=180。U1andU2phasestaggerj=60°,wherethethirdharmonicisstagger3×60°=180.變壓器串聯(lián)合成后，3次諧波互相抵消，總輸出電壓中不含3次諧波。Afterthetransformerissynthesizedinseries,thethreeharmonicscanceleachother,andthetotaloutputvoltagedoesnotcontainthethirdharmonics.uo波形是120°矩形波，含6k±1次諧波，3k次諧波都被抵消。TheUOwaveformisa120°rectangularwavecontaining6K±1harmonics,withall3Kharmonicscancelled.三相電壓型二重逆變電路的工作原理

Theworkingprincipleofthree-phasevoltage-typedoubleinvertercircuit圖3三相電壓型二重逆變電路Fig.3three-phasevoltage-typedualinvertercircuit由兩個(gè)三相橋式逆變電路構(gòu)成，輸出通過(guò)變壓器串聯(lián)合成。Itiscomposedoftwothree-phasebridgeinvertercircuits,andtheoutputissynthesizedinseriesthroughatransformer.兩個(gè)逆變電路均為180°導(dǎo)通方式。Bothinvertercircuitsare180°onconductionmode.逆變橋II的相位逆變橋I滯后30°。PhaseinverterbridgeIofinverterbridgeIIlags30°.T1為Δ/Y聯(lián)結(jié)，線電壓變比為

（一次和二次繞組匝數(shù)相等)。T1forΔ/Yconnection,linevoltagechangeratiois

(primaryandsecondarywindingisequaltothenumberofturns).T2一次側(cè)Δ聯(lián)結(jié)，二次側(cè)兩繞組曲折星形接法，其二次電壓相對(duì)于一次電壓而言，比T1的接法超前30°，以抵消逆變橋II比逆變橋I滯后的30°。這樣，uU2和uU1的基波相位就相同。T2primarysideΔcoupling,secondarysidetwowindingwindingstarconnection,thesecondtimerelativetotheprimaryvoltage,voltagethanaT1connectionaheadof30°,tooffsettheinverterbridgeIIthaninverterbridgeIlagof30°.

Thus,thefundamentalwaveofUU2andUU1isthesame.

Multipleinvertercircuitsandmulti-levelinvertercircuits5.6多重逆變電路和多電平逆變電路

UA21UUNUU2-UB22UU1(UA1)tOtOtOtOtO3131)(1+)UU1UA21-UB22UU2UUN(UA1)UdUd32Ud31Ud32Ud(1+Ud31Ud圖4二次側(cè)基波電壓合成相量圖Fig.4.Syntheticphasordiagramoffundamentalwavevoltageonsecondaryside圖5三相電壓型二重逆變電路波形圖Fig.5Waveformdiagramofthree-phasevoltagetypedualinvertercircuitMultipleinvertercircuitsandmulti-levelinvertercircuits5.6多重逆變電路和多電平逆變電路由圖5可看出uUN比uU1接近正弦波。ItcanbeseenfromFigure5thatUUNisclosertosinewavethanUU1.直流側(cè)電流每周期脈動(dòng)12次，稱(chēng)為12脈波逆變電路。DCsidecurrentpulsates12timespercycle,called12pulseinvertercircuit.使m個(gè)三相橋逆變電路的相位依次錯(cuò)開(kāi)p/(3m)，連同合成輸出電壓并抵消上述相位差的變壓器，就可構(gòu)成6m的脈波逆變電路。ThephaseoftheMthree-phasebridgeinvertercircuitisstaggeredP/(3m),togetherwiththesynthesisoftheoutputvoltageandoffsetthephasedifferenceofthetransformer,canconstitutethe6mpulseinvertercircuit.圖7電壓型三相橋式逆變電路的工作波形Fig.7Workingwaveformofvoltage-typethree-phasebridge-typeinvertercircuittOtOtOtOtOtOtOtOa)b)c)d)e)f)g)h)uUN'uUNuUViUiduVN'uWN'uNN'UdUd2Ud3Ud62Ud3多電平逆變電路

Multi-levelinvertercircuit圖6二電平逆變電路Fig.6Two-levelinvertercircuitMultipleinvertercircuitsandmulti-levelinvertercircuits5.6多重逆變電路和多電平逆變電路以N’為參考點(diǎn)，輸出相電壓有Ud/2和-Ud/2兩種電平，稱(chēng)為兩電平逆變電路。WithN'asthereferencepoint,theoutputphasevoltagehasUD/2and-UD/2twolevels,whichiscalledthetwo-levelinvertercircuit.圖8三電平逆變電路Three-levelinvertercircuitMultipleinvertercircuitsandmulti-levelinvertercircuits5.6多重逆變電路和多電平逆變電路多電平逆變電路

Multi-levelinvertercircuit

三電平逆變電路

Three-levelinvertercircuit也稱(chēng)中點(diǎn)鉗位型逆變電路Also

calledmidpointclamp-typeinvertercircuit每橋臂由兩個(gè)全控器件串聯(lián)構(gòu)成，兩者中點(diǎn)通過(guò)鉗位二極管和直流側(cè)中點(diǎn)相連。Eachbridgearmiscomposedoftwofullycontrolleddevicesinseries,andthemidpointofthetwoisconnectedthroughaclampdiodeandthemidpointoftheDCside.Multipleinvertercircuitsandmulti-levelinvertercircuits5.6多重逆變電路和多電平逆變電路圖8三電平逆變電路Three-levelinvertercircuit多電平逆變電路

Multi-levelinvertercircuit以U相為例分析工作情況TakeUphaseasanexampletoanalyzetheworkingsituationV11和V12（或VD11和VD12）通，V41和V42斷，UO'間電位差為Ud/2。V11andV12(orVD11andVD12)areon,V41andV42areoff,andthepotentialdifferencebetweenUO'isUd/2.V41和V42（或VD41和VD42）通，V11和V12斷，UO’間電位差為-Ud/2。V41andV42(orVD41andVD42)on,V11andV12off,thepotentialdifferenc