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1、OverviewOfPowerElectronicDevices电力电子器件概述孙闯（上海发电设备成套设计研究院，学号P200909071）OverviewOfPowerElectronicDevicesSunChuang(ShanghaiPowerEquipmentResearchInstitute,MinhangDistrict,Shanghai,200240,China)ABSTRACT:Giventhecharacteristicsofanidealpowerelectronicdevice,andc
2、lassifiedtheexistingpowerelectronicdevices.KEYWORDS:idealpowerelectronicdevice;switchingcharacteristics1.ThecharacteristicsofanidealpowerelectronicdeviceTherearemanytypesofpowerswitchingdevices,however,hasitsadvantagesanddisadvantagesandissuitabletospecific
3、applications.Themotivationbehindthedevelopmentofanynewdeviceistoachievethecharacteristicsofanidealswitch.Therefore,thecharacteristicsofanyrealdevicecanbecomparedandevaluatedwithreferencetothecharacteristicsofanidealswitch.Thecharacteristicsofanidealpowerele
4、ctronicdeviceareasfollows[1]:1.1Intheon-statewhentheswitchison,itmusthave(a)theabilitytocarryahighforwardcurrent,tendingtoinfinity;(b)alowon-stateforwardvoltagedrop,tendingtozero;and(c)alowon-stateresistance,tendingtozero.Lowcauseslowon-statepowerloss.These
5、symbolsarenormallyreferredtounderdcsteady-stateconditions.1.2Intheoff-statewhentheswitchisoff,itmusthave(a)the6OverviewOfPowerElectronicDevicesabilitytowithstandahighforwardorreversevoltage,tendingtoinfinity;(b)alowoff-stateleakagecurrent,tendingtozero;and(
6、c)ahighoff-stateresistance,tendingtoinfinity.Highcauseslowoff-statepowerloss.Thesesymbolsarenormallyreferredtounderdcsteady-stateconditions.1.1Duringtheturn-onandturn-offprocess,itmustbecompletelyturnedonandoffinstantaneouslysothatthedevicecanbeoperatedathi
7、ghfrequencies.Thus,itmusthave(a)alowdelaytime,tendingtozero;(b)alowrisetime,tendingtozero;(c)alowstoragetime,tendingtozero;and(d)alowfalltime,tendingtozero.1.2Forturn-onandturn-off,itmustrequire(a)alowgate-drivepower,tendingtozero;(b)alowgate-drivevoltage,t
8、endingtozero;and(c)alowgate-drivecurrent,tendingtozero.1.3Bothturn-onandturn-offmustbecontrollable.Thus,itmustturnonwithagatesignal(e.g.,positive)andmustturnoffwithanothergatesignal(e.g.,zeroornegative
