Topic 10Main contentsLast lecture reviewHalf-Bridge and Full-Bridge ConverterPush-Pull Converter Comparison of isolated converterSummary
Main contents • Last lecture review • Half-Bridge and Full-Bridge Converter • Push-Pull Converter • Comparison of isolated converter • Summary Topic 10
1.1Half-BridgeConverter1convertercircuitODi(t)i0D30888200Vs(t)R880本CbD4DOHalf-Bridge converter requires two split capacitors Ca and Cp toform a dc input mid-point.The switches Q, and Qz are turned on alternatively, each for aninterval ton
1.1 Half-Bridge Converter Half-Bridge converter requires two split capacitors Ca and Cb to form a dc input mid-point. The switches Q1 and Q2 are turned on alternatively, each for an interval ton. 1 converter circuit
2.Principlesof Half bridge converter(1)WhenT,isONandT,isOFF十1本TC12+NuoiNiVV1YY1N,Va/2NVoiTCN,Va1CLou21ot2N.2T/2N, VaVAVN.2I。ip2=0ipi=it
2. Principles of Half bridge converter 1 21 1 2 oi L o N 2 v N1 2 v = Vd ,u = v = N2Vd = N2Vd −V iD1 = iL iD 2 =0 (1) When T1 is ON and T2 is OFF
(2) T, is OFF and T, is ON公+DI.+CL本DVCNuoi03N,3LViT2本C2T2N,V./2NVoiN,VaVaWoi=-V22V2N, 2tonN2VaT/2VAV2N,ipi= 0ip2=it
T2 1 22 1 oi L o N 2 v N1 2 v = − Vd u = −v = N2Vd 2 = N2Vd −V iD1 = 0 iD 2 =iL (2) T1 is OFF and T2 is ON
(3) Both T, and T2 are OFFD本Ti+CV+Voi = 0Vi=-V.UoiNiVND2ipr=iTD2本2C(a)TD =-Ian<0.5S+△：onN2Va/2NVoi2T,?In the condition of steady-state:oN.0+(-V)(s-tar0=0AtonTA-+OrN, 2T/2VN.NL2DVdNiNi T,I。T.is definedgenerallywhereD0Keep in mind!Ts(b)
(a) voi 00 tt N 2 V d / 2 N 1 ton Ts /2 iL Io Vo (b) D1 D2 C1 L i L Io +v1 - + R uoi - +Vd Vd /2C2 - + Vo - N1 N2 T 1 T 2 N2 D 1 D 2 i voi = 0 vL = − Vo i = i = L2 (3) Both T1 and T2 are OFF 2 on s t + = Ts , D = ton 0.5 T In the condition of steady -state: 1 2 o on o on o 2 on N V T N 2 2 D Vd N1 Ts N1 + ( −V )( s − t ) = 0 V = N t = N （ 2 d − V ） t D = Ton TS is defined generally. Keep in mind! where