三電平有源濾波器控制系統(tǒng)研究.pdf

1、華中科技大學碩士學位論文三電平有源濾波器控制系統(tǒng)研究姓名：黃柱申請學位級別：碩士專業(yè)：電力電子與電力傳動指導教師：鄒云屏20060428IIABSTRACTDuetothelimitationofthevoltagecapabilityofthepowerdevicesitisverydifficulttohlethenonlinearloadsfthetraditionalactivepowerfilter(APF)withtwole

2、velinverterinhighvoltagegrid.Inrecentyearsmultileveltechnologyhasbecomeaneffectivepracticalsolutionfhighvoltagehighpowerapplicationfield.Asdescribedinmanyliteraturesusingmultileveltechnologythevoltagestressonswitcheswill

3、bereducedtheshapeofoutputwavefmwillbeimprovedtherateofvoltagepowercanbeincreasedtoo.Diodeclampedthreelevelinverteristhemostwidelyusedinvestigatedtopologyatpresent.ThepaperdescribethetheeticbasesoftheproposedAPF.Themathem

4、aticmodelinABCthreephasestatcodinateofthethreelevelAPFissetup.Usingcodinatetransfmationthemathematicmodelindqtwophaserotatingcodinateisestablished.Tocontrolthewavefmshapeofoutputcurrentthispaperpresentedarepetitivepredic

5、tionbaseddeadbeatcontrolscheme.Inthisschemethepredictiveharmoniccurrentvalueisobtainedbytherepetitivepredict.Therepetitivepredictcanachievebetterpredictionoftheharmoniccurrentwithsamesamplingfrequencythusimprovestheovera

6、llperfmanceofthesystem.Threephasecommvoltagescansynthesizearotatespacevoltagevect.InthispaperthemethodofhowtoattainspacevoltagevectbySVPWMmodulationstrategyinthreelevelAPFisdiscussed.amodulationstrategythatcanreduceswitc

7、hinglossisintroducedtoo.ThispaperresearchestheissuesofneutralpointvoltagecontrolfromthespacevectPWM（SVPWM）pointofviewindetail.Theinfluencesofeveryswitchingstateonneutralpointareanalyzed.Thenaneutralpointcontrolmethodwhic

8、hisbasedonthedetectionofthethreephaseoutputcurrenttheneutralpointripple’sdirectionsisadoptedinthispaper.Thispaperadoptsanoptimalapproachofcalculatingthecommcurrentundercapacitylimitation.InthisAPFifthedetectedharmoniccur