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1、爵衄绥锦违岂锑详题知泵拧Modernfrequencychangertechnicalanalysis桄摹高贫矩昕勒迷眼怔恍迹ChengXi(Heilongjianglongmaymininggroupco.,ltd.)幛虎句蘖毒倘琴疽登莩撤天Thegeneralfrequencychangerbyitsmeritsandsoonintellectualization,digitization,networkreceivespeople'sfavormoreandmore,butalongwiththegen
2、eralfrequencychangerapplicationscope'sexpansion,exposessomequestions.Inviewofthesequestions,thisarticlecarriedonhasanalyzedandproposedthecountermeasure.缥羝觊恶敢镔饶讣酤枢馥謇First,overtonequestionandcountermeasure.刘苒芗犄模劫擂嗑馄婷缭乍Thegeneralfrequencychanger'smaincircuitfo
3、rmgenerallybytherectificationpart,thecontravariantpartandthefilterpartiscomposed.Therectificationpartforthethree-phasebridge-typeuncontrolledrectifier,theinvertorspartistheIGBTthree-phasebridge-typeinvertors,andtheoutputisthePWMprofile.Becausethegeneralfreq
4、uencychanger'srectificationpartusesthediodeuncontrolledbridge-typelevelingcircuit,themiddlefilterpartusesthebigelectriccapacitytotakethefilter,thereforerectifier'sinputcurrentinfactiscapacitor'schargingcurrent,assumesahighermoreandprecipitouspulsewave,itsha
5、rmoniccomponentisbig.Fortheharmoniccancellation,mayuse:衫畅坟饺嘈误脑具刊租年脓1,Increasesthefrequencychangerelectricpowersupplyinternalresistance.Usuallyinthesituation,powerequipment'sinternalresistancemayplaythecushionfrequencychangerconcurrentfilterelectriccapacity'
6、sreactivepowerrole.Thiskindofinternalresistanceistransformersshort-circuitimpedance.Whenpowersourcecapacityrelativefrequencychangercapacityhour,thentheinternalresistancevaluerelativelyisbigger,theharmoniccontentissmaller;Whenthepowersourcecapacityrelativefr
7、equencychangercapacityisbigger,thentheinternalresistancevaluerelativelyisbigger,theharmoniccontentisbigger.Thereforebestchoiceshort-circuitimpedancebigtransformer.扳钺毂亟雌碘这搏瘗匀猕钮2,Installsthereactor.Installsthereactorisactuallyincreasesthefrequencychangerelect
8、ricpowersupply'sinternalresistancefromexterior.Installsthedirect-currentreactorinfrequencychanger'sexchangesideinstallmentexchangereactororinfrequencychanger'sdirect-currentside,alsoorinstalls,suppress
