1144312076--IGBT-驱动电路设计精髓.ppt

IGBTGateDriverCalculationGateDriverRequirement

Whatisthemostimportantrequirement

foran

IGBTdriver?GatePeakcurrent

ConditionsforasafetyoperationWhichgatedriverissuitableforthemoduleSKM200GB128D?Designparameters:fsw=10kHzRg=?reverserecoverycurrentDiodeshouldbe-1.5xIdiodeby80degreecase130Ax1.5=195AGateresistorinrangeof“test–gateresistor”

Howtofindtherightgateresistor?Rg=7OhmTwogateresistorsarepossibleforturnonandturnoffRon=7OhmRoff=10Ohm195A–maxreverserecoverycurrent

DifferencebetweenTrench-andSPTTechnologyTrenchTechnologyneedsasmallerGatechargeDriverhastoprovideasmallerGatechargeSPTTechnologyneedsmoreGatechargecomparedtoTrenchTechnologyDriverhastoprovideahigherGatecharge

Driverperformance–differentIGBTtechnologiesneedsdifferentgatechargeTrenchIGBTwithsamechipcurrentGatechargeis2.3uC

Driverperformance–differentIGBTtechnologiesneedsdifferentgatechargeSPTIGBTwithsamechipcurrentGatechargeis3uC

DemandsforthegatedriverThesuitablegatedrivermustprovidetherequiredGatecharge(QG)–powersupplyofthedrivermustprovidetheaveragepowerAveragecurrent(IoutAV)–powersupplyGatepulsecurrent(Ig.pulse)–mostimportantattheappliedswitchingfrequency(fsw)

-8151390DeterminationofGateChargeGatecharge(QG)canbedeterminedfromfig.6oftheSEMITRANSdatasheet?QG=1390nCThetypicalturn-onandturn-offvoltageofthegatedriverisVGG+=+15VVGG-=-8V

CalculationoftheaveragecurrentCalculationofaveragecurrent:IoutAV=P/?U?V=+Vg+[-Vg]withP=E*fsw=QG*?V*fsw?IoutAV=QG*fsw=1390nC*10kHz=13.9mAAbsolutevalue

PowersupplyrequirementsGatechargeThepowersupplyorthetransformermustprovidetheenergy(Semikronisusingpulsetransformerforthepowersupply,wemustconsid