同步整流的基本原理

29120072JOURNALOFEEEVol.29No.1Feb.2007黄海宏,王海欣,张毅(合肥工业大学电气与自动化工程学院,安徽合肥230009):MOSFET,,DC/DC,!,MOSFET,:;MOSFET;:TM46:A:1008-0686(2007)01-0027-03TheFundamentalofSynchronousRectificationHUANGHaihong,WANGHaixin,ZHANGYi(Schoolofelectricandautomationengineering,HefeiUniversityofTechnology,Hefei230009,China)Abstract:ThetechnologyofsynchronousrectificationistoreplacerectifyingdiodewithpowerMOSFETwhichhaslowturnonresistance,soitcandecreasethedissipationofrectifiercircuitgreatly,improvetheefficiencyofDC/DCconverterandmeettheneedsoflowvoltageandlargecurrentrectifier.ThepaperanalyzestheprinciplediagramofsynchronousrectificationcircuitinPowerElectronics,introducesthereversedresistanceworkareaofpowerMOSFETandbasicprincipleofsynchronousrectificationtechnology.Atlast,thedrivecircuitofsynchronousrectifierandgridvoltagewaveareanalyzed.Keywords:synchronousrectification;powerMOSFET;lowvoltageoutput0DC/DC3:,,,,10~12V,,04V~08V,,,,DC/DC1MOSFET1[1]MOSFETFQP140N03LMOSFET(UDS=30V,ID=140A),38m,20A,76mVMOSFET,,[1]1MOSFET:2006-10-01;:2006-12-14:(1973-),,,,1,MOSFETSD,,2,1MOSFETV1V22,2uT,V1,V2ao,V2VD2,,MOSFET,MOSFET,MOSFET,MOSFET,,3,[2](3)3UDS0,UT(UT),PUDS0,IDUDS,1,V1V23MOSFETuT,V1V2,MOSFET,MOSFET,:ugs=0uds0Ug1,uds0(1),Ug1,,MOSFET(1),uT,V1V2uT1,2,1MOSFET,V1VF1VD1,V2VF2VD2(6)4,VF1VF2ug1ug2uT1,uT1,ug1=ug2=0,VF1VF2,MOSFETVD1VD2VD1VD2,5,uT1282945VF1VF2,,uT1,UT,VF1VF2,N3,66VF1VF2C1C2,VF1VF2,(1),uT1VF1VF2771)0~t0:uT1uT2,uT2=UT2m,VD4,VD3uT2VD4C1,C2VD4ug1=UT2m-UD=USaUT,ug2=-UD,UDVD4,VF1VF22)t0~t1:uT2=0,VD3VD4,C1C2,,ug1=ug2=UT2m/2-UD=USbUTug1ug2UT,VF1VF2,L3)t1~t2:uT2=-UT2m,VD3,VD4,uT2VD3C2,C1VD3ug2=UT2m-UD=USaUTug1=-UD,VF1VF24)t2~t3:uT2=0,VD3VD4,C2C1,,ug1=ug2=UT2m/2-UD=USbUTug1ug2UT,VF1VF2,L:[1],(4)[M]:,2004[2][M]:,2006291: