5.4電壓型逆變電路 Voltage type inverter circuit中英版

Voltagetypeinvertercircuit5.4電壓型逆變電路TeachingResourcesDatabaseof

NationalVocationalEducationPowerSupplyTechnologyBilingualcourses.Powerelectronicstechnology電力電子技術(shù)Item5InverterCircuit項目五逆變電路1、電壓型逆變電路半橋逆變電路工作原理Theworkingprincipleofvoltage-typeinverterhalf-bridgeinvertercircuitVoltagetypeinvertercircuit5.4電壓型逆變電路圖2

電壓型半橋逆變電路及其電壓電流波形Fig.2Voltage-typehalf-bridgeinvertercircuitanditsvoltagecurrentwaveform

在一個周期內(nèi)，電力晶體管T1和T2的基極信號各有半周正偏，半周反偏，且互補。Inonecycle,thebasesignalsofthepowertransistorsT1andT2havesemi-cyclepositivebiasandsemi-cyclenegativebiasrespectively,andarecomplementary.若負載為阻感負載，設(shè)t2時刻以前，T1有驅(qū)動信號導通，T2截止，則u0=Ud/2。Iftheloadisresistiveload,itisassumedthatbeforethetimeT2,thedrivesignalinT1isonandT2isoff,thenu0=Ud/2.

t2時刻關(guān)斷的T1，同時給T2發(fā)出導通信號。由于感性負載中的電流i。不能立即改變方向，于是D2導通續(xù)流，u0=－Ud/2

。T1shutsoffattimeT2,andsendsaconductionsignaltoT2.Becausethecurrenti。intheinductiveloadcannotchangedirectionimmediately,soD2conductioncontinuesthecurrent,u0=Ud/2.t3時刻i。降至零，D2截止，T2導通，i。開始反向增大，此時仍然有u0=－Ud/2

。AtT3,i。dropstozero,D2stops,T2turnson,andi。startstoincreaseintheoppositedirection,sothereisstillu0=Ud/2.在t4時刻關(guān)斷T2，同時給T1發(fā)出導通信號，由于感性負載中的電流i。不能立即改變方向，D1先導通續(xù)流，此時仍然有u0=Ud/2；AtthetimeofT4,T2isshutoffandaconductionsignalissenttoT1.Sincethecurrenti。intheinductiveloadcannotchangedirectionimmediately,D1leadstothecontinuationofthecurrent.Atthistime,thereisstillu0=Ud/2.t5時刻

i。降至零，T1導通，u0=Ud/2；AtthetimeT5,i。dropstozero,T1conduction,u0=Ud/2;電壓型單相半橋逆變電路的特點

Characteristicsofvoltage-typesingle-phasehalf-bridgeinvertercircuit缺點：Disadvantages:1）交流電壓幅值僅為Ud/2；ACvoltageamplitudeisonlyUd/2;2）直流側(cè)需分壓電容器；DCsideneedsvoltagedividercapacitor;3）為了使負載電壓接近正弦波通常在輸出端要接LC濾波器，輸出濾波器LC濾除逆變器輸出電壓中的高次諧波。Inordertomaketheloadvoltageclosetothesinewave,LCfilterisusuallyconnectedattheoutputend,andtheoutputfilterLCfiltersoutthehigh-orderharmonicsintheoutputvoltageoftheinverter.優(yōu)點：簡單，使用器件少；Advantages:simple,uselessdevices;應(yīng)用：用于幾kW以下的小功率逆變電源；Application:forafewkWbelowthelow-powerinverterpowersupply;Voltagetypeinvertercircuit5.4電壓型逆變電路1、電壓型單相全橋逆變電路電路工作過程：Voltagetypesingle-phasefull-bridgeinvertercircuitworkingprocess:Voltagetypeinvertercircuit5.4電壓型逆變電路全控型開關(guān)器件T1和T4構(gòu)成一對橋臂，T2和T3構(gòu)成一對橋臂,T1和T4同時通、斷；T2和T3同時通、斷。T1(T)4與T2(T3)的驅(qū)動信號互補，即T1和T4有驅(qū)動信號時，T2和T3無驅(qū)動信號，反之亦然，兩對橋臂各交替導通180°。Full-controlswitchdeviceT1andT4constituteapairofbridgearms,T2andT3constituteapairofbridgearms,T1andT4areonandoffatthesametime;

T2andT3areonandoffsimultaneously.

ThedrivingsignalsofT1(T)4andT2(T3)arecomplementary,thatis,whenT1andT4havedrivingsignals,T2andT3havenodrivingsignals,andviceversa,andthetwopairsofbridgearmseachconductalternatelyat180°.圖2

電壓型半橋逆變電路及其電壓電流波形Fig.2Voltage-typehalf-bridgeinvertercircuitanditsvoltagecurrentwaveform

輸出方波電壓瞬時值：Outputsquarewavevoltageinstantaneousvalue:

輸出方波電壓有效值：Effectivevalueofoutputsquarewavevoltage:基波分量的有效值：Effectivevalueoffundamentalwavecomponent:同單相半橋逆變電路相比，在相同負載的情況下，其輸出電壓和輸出電流的幅值為單相半橋逆變電路的兩倍。Comparedwithsingle-phasehalf-bridgeinverter,underthesameload,theamplitudeofoutputvoltageandoutputcurrentistwicethatofsingle-phasehalf-bridgeinverter.1）純電阻負載時

WhenpureresistanceloadVoltagetypeinvertercircuit5.4電壓型逆變電路圖2

電壓型半橋逆變電路及其電壓電流波形Fig.2Voltage-typehalf-bridgeinvertercircuitanditsvoltagecurrentwaveform

2）電感負載時

Whentheinductorisloaded由可得負載電流峰值為：Voltagetypeinvertercircuit5.4電壓型逆變電路圖2

電壓型半橋逆變電路及其電壓電流波形Fig.2Voltage-typehalf-bridgeinvertercircuitanditsvoltagecurrentwaveform

0≤t＜Ts／4，Ts2≤t≤3Ts／4期間，D1、D4導通起負載電流續(xù)流作用，在此期間T1～T4均不導通。Duringtheperiodof0≤t<TS/4andTS2≤T≤3TS/4,D1andD4conductionplaystheroleofloadcurrentcontinuation.Duringthisperiod,T1-T4isnotconduction.Accordingtothepeakvalueofloadcurrentcanbe:3）阻感負載RL時

WhentheresistiveloadisRL圖2(e)所示是RL負載時直流電源輸入電流的波形。Figure2(e)showsthewaveformoftheDCinputcurrentatRLload.Voltagetypeinvertercircuit5.4電壓型逆變電路圖2

電壓型半橋逆變電路及其電壓電流波形Fig.2Voltage-typehalf-bridgeinvertercircuitanditsvoltagecurrentwaveform

0≤θ≤ωt期間，T1和T4有驅(qū)動信號，由于電流i0為負值，T1和T4不導通，D1、D4導通起負載電流續(xù)流作用，u0=+Ud。During0≤θ≤ωt,T1andT4havedrivingsignals,becausethecurrentI0isnegative,T1andT4donotconduct,D1andD4conductionplaytheroleofloadcurrentcontinuation,u0=+Ud.θ≤ωt≤π期間，i0為正值，T1和T4才導通。Duringθ≤ωt≤π,whenI0ispositive,T1andT4conduct.π≤ωt≤π+θ期間，T2和T3有驅(qū)動信號，由于電流i0為負值，T2、T3不導通，D2、D3導通起負載電流續(xù)流作用，u0=－Ud。Duringπ≤ωt≤π+θ,T2andT3havedrivingsignals,becausethecurrentI0isnegative,T2andT3donotconduct,D2andD3conductionplaysaroleofloadcurrentcontinuation,u0=－Ud

.π+θ≤ωt≤2π期間，T2和T3才導通。T2andT3conductduringπ+θ≤ωt≤2π.Thanksforwatching