Abstract—A rigorous mathematical analysis and a comparative study of carrier-frequency modulation (CFM) techniques for the conducted electromagnetic interference (EMI) suppression in pulsewidth-modulated converters is presented. CFM techniques dither the
TSEetal.:CARRIER-FREQUENCYMODULATIONTECHNIQUESbeendeveloped.Inaddition,duetothefinitebandwidthoftheresolutionfilterinEMCanalyzers,discrepanciesbetweenthetheoreticalandexperimentalresultshavebeenexplained.SelectionsofthemodulationfrequencyandthefrequencydeviationinPCFMhavebeendiscussed.Finally,theoreticalpredictionsareconfirmedbyexperimentalresultsofabuckconverteroperatingincontinuousconductionmode.
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K.K.Tse(M’00)receivedtheB.Eng.(Hons.)degreeinelectricalengineeringfromTheHongKongPoly-technicUniversity,HongKong,andthePh.D.degreefromCityUniversityofHongKong,HongKong,in1995and2000,respectively.
HeservedasaLecturerattheHongKongInstituteofVocationalEducation(TsingYi)(formerlyTech-nicalCollege)in1998.From1999to2001,hewasaResearchFellowintheElectronicEngineeringDe-partment,CityUniversityofHongKong.SinceJune2001,hehasbeenwithJohnsonElectric,HongKong,
whereheiscurrentlyaTechnicalSpecialistintheR&Darea.Hehasauthoredmorethan20publishedtechnicalpapersintheareasofhisresearchinterests,whichincludenewnumericalmodelmethodsandcomputer-aidedsimulationtechniques,EMIreductionusingrandomswitchingschemesfordc–dccon-verters,andnewmaximumpowertrackingtechniquesforPVcells.
Dr.TsereceivedtheFirstPrizein1998intheIEEEPostgraduateStudentPaperContest,HongKongSection,andtheThirdPrizeinthe1999Region10IEEEPostgraduateStudentPaperContest.HewasarecipientofTheCroucherFoundationFellowshipin2000.InDecember2000,hereceivedtheSilverAwardintheYoungInventorCompetition,jointlyorganizedbytheFarEasternEconomicReviewandHewlettPackard
Company.
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HenryShu-HungChung(S’92–M’95)receivedtheB.Eng.(withfirstclasshonors)degreeinelectricalengineeringandthePh.D.degreefromTheHongKongPolytechnicUniversity,HongKong,in1991and1994,respectively.
Since1995,hehasbeenwithCityUniversityofHongKong,HongKong,whereheiscurrentlyanAssociateProfessorintheDepartmentofElectronicEngineering.Hisresearchinterestsincludetime-andfrequency-domainanalysisofpowerelectroniccir-cuits,switched-capacitor-basedconverters,random-switchingtechniques,digitalaudioamplifiers,soft-switchingconverters,andelectronicballastdesign.Hehasauthoredfourresearchbookchaptersandmorethan130technicalpapers,including65refereedjournalpapersinthecurrentre-searcharea,andistheholderoftwoU.S.patents.
Dr.ChungiscurrentlytheIEEEStudentBranchCounseloratCityUniversityofHongKongandwasTrackChairoftheTechnicalCommitteeonPowerElec-tronicsCircuitsandPowerSystemsoftheIEEECircuitsandSystemsSocietyin1997–1998.HeispresentlyanAssociateEditoroftheIEEETRANSACTIONSONCIRCUITSANDSYSTEMSI.HewasawardedtheGrandAppliedResearchEx-cellenceAwardin2001fromCityUniversityofHong
Kong.
S.Y.RonHui(SM’94)wasborninHongKongin1961.HereceivedtheB.Sc.(Hons.)degreein1984fromtheUniversityofBirmingham,Birmingham,U.K.,andtheD.I.C.andPh.D.degreein1987fromImperialCollegeofScienceandTechnology,UniversityofLondon,London,U.K.
HewasaLecturerinpowerelectronicsattheUniversityofNottingham,Nottingham,U.K.,in1987–1990.In1990,hetookupalectureshipattheUniversityofTechnology,Sydney,Australia,wherehebecameaSeniorLecturerin1991.Hejoined
theUniversityofSydneyin1993andwaspromotedtoReaderofElectricalEngineeringandDirectorofthePowerElectronicsandDrivesResearchGroupin1996.HeiscurrentlyaChairProfessorofElectronicEngineeringandanAssociateDeanoftheFacultyofScienceandEngineeringatCityUniversityofHongKong,HongKong.Hehasauthoredmorethan150publishedtechnicalpapers,includingmorethan80refereedjournalpublications.Hisresearchinterestsincludeallaspectsofpowerelectronics.
Prof.HuireceivedtheTeachingExcellenceAwardin1999andtheGrandAp-pliedResearchExcellenceAwardin2001fromCityUniversityofHongKong.HehasbeenappointedanHonoraryProfessorbytheUniversityofSydneysince
2000.
H.C.SowasborninHongKong.HereceivedtheB.Eng.degreefromCityUniversityofHongKong,HongKong,andthePh.D.degreefromChineseUni-versityofHongKong,HongKong,in1990and1995,respectively,bothinelectronicengineering.
From1990to1991,hewasanElectronicEngineerintheResearchandDevelopmentDivision,EverexSystemsEngineeringLtd.HewasthenaPost-Doc-toralFellowatChineseUniversityofHongKongforoneyear.From1996to1999,hewasaResearchAs-sistantProfessorintheDepartmentofElectronicEn-gineering,CityUniversityofHongKong.Currently,heisanAssistantProfessorintheDepartmentofComputerEngineeringandInformationTechnology,CityUniversityofHongKong.Hisresearchinterestsincludeadaptivefiltertheory,detectionandestimation,wavelettransform,andsignalprocessingforcommu-nicationsandmultimeda.