电磁炉有关IGBT的翻译

IGBTSelectionMethodfortheDesignofResonantInvertersforDomesticInductionHeatingAbstractThepowertransistor(IGBT)isoneofthemostimportantcomponentsoftheinverterofdomesticinductioncookers.Forthisapplicationthemaximumjunctiontemperature(Tjmax)oftheIGBTisoneofthemostcriticaldesignparametersbecausethecookerhastodecreasetheoutputpowerwhenthejunctiontemperatureisneartoTjmaxofthedevice.Thejunctiontemperature(Tj)oftheIGBTprincipallydependsonthepowerlosses.ThispaperproposesamethodtochoosetheIGBTbasedonthecalculationofthetemperaturevariationΔTjafromthepowerlosses.Nowadays,IGBTbehaviourisatrade-offbetweenconductionandswitchingperformance,soitisnecessarytomeasuretheIGBTpowerlossesseparately.ThispaperproposesamethodtomeasurethepowerlossesseparatelybasedonelectricalmeasurementandtheIGBTconductioncharacteristics.Moreoveritisproposedacriteriontodeterminatethelimitsofthepowerlossesbasedoneliminatetheoffsetofdevicevoltageandtheswitchingareaisdefinedfromthevoltageisover2.5Vtothecurrentiszero.Finally,theproposedmethodhasbeenappliedtofivedifferentIGBTsfordifferentlevelsofpowerandwithtwostandardpanswithanelectronicboardofacommercialcookerMoreoverthismethodhasbeenverifiedwithathermograficcameraobtainingsimilarresults.IntroductionDomesticinductioncookerstaketheenergyfromthemainsvoltage,whichisrectifiedandfiltered.Thentheresonantinvertersupplieshigh-frequencycurrenttotheinductioncoil.Thehalf-bridgeseriesresonantinverter(Fig.1(a))isthemostusedduetotheelectricalrequirementsofitscomponents,itssimplicityanditscost-effectiveness[1].Theresonantloadconsistsofthepanandtheinductioncoil.Theircouplingismodelledastheseriesconnectionofaninductorandaresistor,basedonthetransformeranalogy[2].Domesticinductioncookersenabletoheatthepaninapowerrangebetween3300Wand50W.ThemodulationstrategiestypicallyusedindomesticinductionheatingaretheSquareWave(SW)controlandtheAsymmetricalDutyCycle(ADC)controlforthehighpowerrangeandthePulseDensityModulation(PDM)[3]forthelowpowerrange.Oneofthemostimportantcomponentsofdomesticinductioncookersisthepowertransistor;usuallyitisanIGBTforitsconductionandswitchingcharacteristics.Forthisapplicationthemaximumjunctiontemperature(Tjmax)oftheIGBTisoneofthemostcriticaldesignparametersbecausethecookerhastodecreasetheoutputpowerwhenTjisneartoTjmaxofthedevice.Thisreductionoftheoutputpowerisnotdesirableforthisapplication,sotheoptimumIGBTisthatoneminimizesthisreductionofpowerThejunctiontemperature(Tj)oftheIGBTdependsonthepowerlosses,thecoolingsystem,thethermalcharacteristicsofthedeviceandtheenvironmenttemperature(Ta).Therefrigerationsystemconsistsoftheisolationfoil,theheatsinkandthefanandithassomedesignlimitations.Theextrudedheatsinkislimitedbythereduceddimensionsofthecookerandthefanspeedislimitedfortheacousticnoiselevel.Theenvironmenttemperaturedependsontheinstallationandmainlyifthereisanovenbelowthecookerbecausethistemperaturecouldreach80ºC.Thedevicepowerlossescanbeseparatedinconductionandswitchinglossesandtheycanbeminimizedwiththeappropriatemodulationstrategy[4-5]andIGBT.Nowadays,IGBTbehaviourisatrade-offbetweenconductionandswitchingperformance,soitisnecessarytomeasurethelossesseparately.Fig.1(b)showsthetendencyofthecurrenttechnologylimitsforthiskindofdevice.ThemainparameterforconductionlossesistheSaturationVoltage(VCESAT)andforswitchinglossesistheSwitch-offEnergy(Eoff).Theprincipalthermalcharacteristicsofthedeviceareitsthermalresistancesandthemaximumjunctiontemperature.InthispaperitispresentedamethodtochoosetheIGBTbythecalculationofthetemperaturevariationbetweenthejunctionofthedeviceandtheenvironment(ΔTja)fromthemeasurementofthepowerlosses.MethodtomeasurethepowerlossesCommercialpoweranalyzersandthermalmethodsonlycanmeasurethetotalpowerlosses.Inthispaperisproposedamethodbasedonelectricalmeasurements.Themaindifferencebetweentheproposedmethodandothersworksisthecriteriontoseparateconductionandswitchinglosses.Othersworksproposecriteriabasedonapercentageofthedevicevoltage(vCE)[6-7]orbasedontheslopeofthedevicecurrent(ic)[8].Inthispaper,itisproposedthattheswitchingareabeginswhenthevCEminusthevoltageoffset(Voffset)isover2.5V(selectedtotakeaccountofvoltagesignalnoise)anditfinisheswhenthecurrentiszero(Fig.2).ThevoltageVoffsetistheaverageofvCEduringtheperiodbetweenthediodeturn-offandthebeginningoftheswitchingarea.TheIGBTconductionlossesareconsideredfromthediodeturn-offtotheendofthe“tailcurrent”.ThereasontochoosethiscriterionisthattheconventionaldifferentialprobesdonothaveenoughsensitivitytomeasuretheIGBTconductionvoltage(vCE,ONIGBT)andtheoffsetoftheseprobescanbehigherthanvCE,ONIGBT.Moreover,thiscriterionisindependentofthemaximumdevicevoltageandthemeasurementsystem.A.Conductionpowerlosses.Conductionlosses(Pon)canbeseparateintoIGBTanddiodelosses(Fig.2).Bothlossescanbemodelledastheseriesconnectionofaresistance(Ron)andavoltagesource(Von)[9].Thus,powerlossesarecalculatedasfollowswhereIandIrmsaretheaverageandrmscurrentsduringtheconductionofthedevice.ThemanufacturerofthedeviceprovidesacurveforthediodeandtheIGBTwhereitcanbecalculatedRonandVonaccordingtothed