matlab/simlink model for three phase … · matlab/simlink model for three phase hybrid multilevel...

MATLAB/SIMLINKMODELFORTHREEPHASEHYBRIDMULTILEVELINVERTERBASEDONHALFBRIDGEMODULES

1E.MADHANAGOPAL,2M.SIVASHANKAR,3S.ASHWAKHUSSAIN

1PGstudent,DeptofEEE,RGMcollegeofEnggandTechnology,Nandyal,India,Email:[email protected]

2AssistantProfessor,Dept.ofEEE,RGMcollegeofEnggandTechnologyNandyal,India,Email:[email protected]

3Assistantprofessor,Dept.ofEEE,RGMcollegeofEnggandTechnologyNandyal,India,Email:[email protected]

ABSTRACT

Nowadays the multilevel inverters are widely used in power electronic applications. The multilevel inverters arerecommendedformediumandhighvoltageapplications.Multilevelinvertershavebecomemorepopularduetoreducedswitching losses, low costs, low harmonic distortion and high voltage capability when compared to traditional PWMinverters.Thispaperdealswithhybridmultilevelconverterwhich issynthesizeofneutralpointclampedandcascadedmultilevel inverter.Thehybridmultilevelconverter isproposed formediumvoltage largepowerratings.Theproposedconverter consisting of voltage source inverter connectedwith half bridgemodules at each phase.With the proposedconnection large portion of energy can be preceded by the VSI by connecting singlemulti pulse rectifier. The smallerpowersharesprocessedwithinthehalfbridgemodules.Themodulationschemeforhybridmultilevelinverterisnaturallyachievedbyusinglogiccircuit.Themodulationschemeforfour‐levelversionisanalyzedindetailforhighermodulation(HM), three level version is analyzed for lowermodulation (LM). Thismodulation schemeallowsunidirectional powerflow in all DC sources. For unidirectional application, the diode bridges are employed at rectification input side. Themodulationschemesofsinusoidalpulsewidthmodulation(SPWM),spacevectorPWM(SVPWM)areanalyzedbyusingMATLAB/SIMLINK. The comparison of THD’s for SPWM and SVPWM modulation techniques done by usingMATLAB/SIMLINK.

IndexTerms‐HybridConverters,MultilevelConverters,PWMModulation,ThreePhaseInverters.

1. INTRODUCTION

In recent years industry has demanding high powerequipment which now reach mega watt level multilevelconvertersaremostwidelyused inpowerelectronics forhigh voltage and high power applications. Multilevelconvertersaremainlyutilizedtosynthesisadesiredsingleorthreephasevoltagewaveform.Thedesiredmulti‐satirecaseoutputvoltage isobtainedbycombiningseparatedcsources.Multilevelinverterisdesignedbymorenumberofswitches to obtained stair case output. the multilevelinvertersaremostlyusedinpowerelectronicapplicationslikepowerquality,powersystemcontrol,adjustablespeeddrives uninterruptable power supplies (UPS).in theindustrial applications mostly three phase multilevelinvertersareused.

Nowadays, there exits three types of multilevel voltagesource inverters namely neutral point clamped inverter(NPC),flyingcapacitors(FC’s),cascadedHbridgeinverter(CHB). Among these multilevel inverter cascadedmultilevel inverter is reaches thehighervoltageandhighpower levels. By increasing voltage levels the number ofswitches will increase which leads increasing swathinglosses.[1]‐[12]

Diode clamped converter also known as neutral pointclampedinverter(NPC).[19],[20]whichiswidelyusedinthreephasepowerconversion.Thereisasingledclinkspitin to two or more equal voltages which clamp the mainvoltage of main switches through fast switching diodes.This is used in high power ac drive applications like

conveyers, pumps, fans in mining, Marian, gas, oilindustries.Thecapacitorclampedconverteralsoknownasflyingcapacitorconverter.Theflyingcapacitorconvertersare used in highbandwidthhigh frequency applications.[17]‐[18]

Finally, cascadedmulti level inverter has been applied inhigh voltage, power essential conditions. This cascadedmultilevel inverter employs dc side isolated seriesconnectedfullbridgesallowshighmodularitylessnumberofswitchesascomparedtoNPC,FC.Cascadedhalfbridgeconvertersemploysseries connectedhalfbridgemodulesinstead of full bridge ones. This converter is alternate tothe full bridge ones. The modular multilevel converterprovided of series connected pair of half bridgemodules.[16]

2. HYBRIDMULTILEVELCONVERTER

Hybridmultilevel converter is synthesizemodel of threephase two level voltage source inverter or NPC andcascadedhalfbridgesateachphase.Thehybridmultilevelconverter consisting of two multilevel convertersconnected in back to back. So it is called as hybridcascaded half bridge converter (HCHB).the number ofcomponentsofHCHBissameasperCHBwhichgivessamenumberof levels.Thetreephasetransformerdirectly fedwithout insulation. This reduces the insulationtransformerandcapacitivedclinkstorages.Dependingupon specific application and switching technology HCHBand CHB [13]‐[15] have their advantages anddisadvantages.[8],[12]

E. MADHANA GOPAL et al. DATE OF PUBLICATION: DEC 19, 2014

ISSN: 2348-4098 VOL 2 ISSUE 8 NOV-DEC 2014

INTERNATIONAL JOURNAL OF SCIENCE, ENGINEERING AND TECHNOLOGY- www.ijset.in 143

The work present in this paper is hybrid topology ofmultilevel inverter. In this topology both three‐phaseinverter(NPC)andhalfbridgesconnectedateachphaseininversepolarityasshowninfigure.Thehybridtopologyisnamed as hybrid cascaded half bridge converter. The

connectionofhalfbridgemoduleisguaranteedthatnodclevelisobservedatoutputvoltages.The12pulserectifiergenerates the dc voltage sources which having leastcurrentharmonicsandwelldistributedcurrents.

Figure1:circuitdiagramofproposedhybridmultilevelconverteremployinghalfbridgemodulesandathree‐phaseinverter

For the samenumber of voltage level of CHBorHCHB,thenumberofinsulatedsourcesincreased,theconverterlowerstheratingofthesedevices.ThecurrentdrawnbyhalfbridgemoduleislowerwhencomparedtoHbridgebased converter for six pulse rectifier. Thus higherpowerscanbearchivedforgivenrectifiertechnology.

The possible operation modes proposed converter isdiscussed in section III. The symmetrical four‐levelconverter ispresent indetail.Theunidirectionalpowerflowrequired inmanyapplications,suchashighpowerUPS, co‐generation, and others applications. AmodulationschemeispresentedinsectionIV.Basedontheproposedmodulation,theoutputvoltageisanalyzedin section VI for its harmonic spectrum and totalharmonicdistortion(THD).[21]‐[22]

The circuit simulation of complete four level converteremploying 12pulse rectifier with dc voltage sourceminimum ripple grid side input inductors , thetransformer leakage inductance as have been carriedout. The inverter load is kept constant based onmodulationindex.TwoACgridoperatingconditionsareanalyzed (1) balance grid voltage (2) grid voltageunbalanceby±3%.TheAC‐gridunbalancesleadtohighdistortion and THD. The harmonic distortion furthermaybereducedbyconnectingharmonicfilters.theinputphase current and phase spectrum for LM and HMmodulationinfig2.fig2(a)showsthecurrentwaveformfor LM modulation with modulation index M=0.5.Fig2(b) shows the same variable for HM modulationM=0.9.Theequalamountofenergycanbeprocessedbyeachhalfbridgeatalloperatingconditions.The12pulserectifier isslit in to twoparts,one is two levelVSIand,otherpartissecondaryenergysupplyforallhalfbridgemodules. Thus the conventional 12 pulse rectifiersupplyingtwosecondary’swithbalanceloads.

3. MULTILEVELOPERATION

The following assumptions are made for analyzing ofmultilevelconverter:(1)switchingdevicesareideal;(2)thedcsourcesareconstantpositivevoltages;(3)virtualcentrepointoftheVSI’sdclinkisassumedasreferencetovoltages.considerthephaselegconsistofpairofhalfbridgemodules and one phase leg ofVSI , the possibleoperating stages for phase A of proposed converter isshow inFig .3. theoutputvoltage vAcanbeobtained insixdifferentlevels.Theoutputvoltagescanbeobtainedforthreephasesasvowitho=A,B,C.shownintableI.theoutputvoltage isdependsondcsourcevoltagesVxandVy on the switching states of Sjo and Sjo’ ,with 1, 2,3.Basedontheseresults,theHC1/2BthenumberoflevelsNvaryingfromfourtosixgiventhat

(1)

Based on the switching states the phase voltage levelscanbeobtainedisgiveninTableI.forfourlevelHC1/2Bsymmetrical dc source the space vectors are shown inFig4(a)with.

The resulting state space is composition of VSI spacesandpairofhalfbridgespaces.Forasymmetricalcasethespace vector space is shown in Fig 4(c). to generatephasevoltage in converter it isnotnecessary to switchtheVSIstatebuthalfbridgespacesaregeneratevoltagespacesinconverter.ThatrelativelyincreasingdcvoltageforVSIexpandsVSIspaceandcreateshighernumberoflevels.Thevoltageratingforsemiconductorischangebyspacevectorspace.

Switching stages for hybrid multilevel converter withsinglephaselegare




(a) S1A’,S2A’andS3Aareonand;

(b) S1A,S2A’andS3Aareonand;

(c)S1A’,S2AandS3Aareonand;

(d)S1A,S2AandS3Aareonand;

The output voltage referred as virtual reference shownin centre point of source

Figure2:operationstagesforphaselegofproposedmultilevelconverteremployinghalfbridgemodulesforpositiveoutputvoltage

TABLEI:ResultantOutputPhaseVoltage(Vo,WithO=A,B,C)AsAFunctionOfSwitchingStatesAndOfTheDcSourceValues And Where CorrespondsToTheStateOfSwitch Asnd (SwitchOn;1,SwitchOff;0)

Case1

Case2

Case3

0

1

0

1

0

0

1

1

0

0

0

0

0

1

0

1

0

0

1

1

1

1

1

1




Figure4:Spacevectorsforproposedconverter(a)spacevectorsforfourlevelconverteremploying;(b)contributionsformodulationdomainfor,and(c)contributionformodulationdomain.

4. MODULATION SCHEME FOR FOUR‐LEVELCONVERTER

ThissectionpresentsthemodulationschemeforfourleveloperationofHC1/2B.Inthisconvertertheswitchesofthethree‐phase VSI at low frequency transfer the switchinglosses to half bridge modules. This feature allows usinglow speed switches in three phase inverter reducingconduction losses in VSI. While keeping the switchinglosses at same level, the losses shifted to half bridgemodules.Thenonuniformdistributionofswitchinglossesoccur, themodulation scheme is able to distribute lossesamongthehalfbridgemodules.Byswitchingtheswitchesand with o=A, B, C and j=1, 2, 3in complementaryway.ForthegenerationofthreephaseVSIswitchingsignalswedevelop demand logic. Thus this modulation strategy isknownas hybridmodulation.As it usedhighmodulationindexes it is named as HM. the half bride modules arederived by comparing sinmodulating signalRefj to threesynchronoustriangularcarrierCarjasshowninFig3(a).

Uncontrolledrectifierscanbeemployedforunidirectionalpowerflowapplicationsbyconnectingalldcsources.Thepositive and negative power flow shown in Table II atsomeofinsulateddcsourcesdoesnotdependonlyontheswitching states but also on direction of phase currents.Themodulationpatternpreviouslydescribedisnotabletoguaranteeunidirectionalpowerflowindcsourcesforthehalf bridge modules for modulation index ranging fromnulltounity.

TheoutputvoltagesofVSI arekept constantduringeachhalfperiodandthisforcethehalfbridgemodulesprocessmore power and regenerate it to the source of lowmodulation indexes. It is clearly observed in Fig 6 thepower flow at insulated dc source become negative forM<0.42 and active power handled by all dc sources

extremelyhighatlowmodulationindexeswhencomparedtototalactivepowertransferredtoload.

Figure3:ModulationstrategyHM:(a)timingdiagramforfourleveloperationand(b)PWMgenerationlogic

Outputphasevoltage(o=a,b,c)andactivepowerdirectionat the dc sources as a function of switching states, andoutput currents direction. And are the average powerproceeded by upper and lower dc sources respectively.Feedingthehalfbridgemodulesatphaseo,theplussignal(+) indicates that the source is feedingpower. theminussignalindicatesthatthesourceissinkingpower.theemptysignal(φ)indicatesthatnocurrentflowinthesource.




Figure4:ActivepowerhandlesbydcsourcesasapercentofthetotalloadpowertotalmodulationpatternHM

One way to avoid the regenerative power flow in theinsulateddcsourceistoswitchthethreephaseVSIathighfrequency ,generating output PWM voltages withsinusoidal behavior proportional to modulation index.SwitchinglossesattheVSIwouldincreaseaccordingly.Sothe modification of modulation logic proposed. The VSIhighsidearelowsideswitchesareturnedonduringwholeperiod when M<1/2 .the modulation pattern M<1/2 isshowninFig7termedasmodulationLM.

Themodulationschemebasicalgorithmisasfollows.

0≤M≤1/2(LM):theVSIhasallswitcheseitherclampedtothepositiveornegativerail.Theclampingcanbechangedateverymodulationcycletobalancethelossesat all semiconductors or, whenever possible a bypassmechanical switch can be driven to reduce conductionlosses. The half bridge process all the active powertransferredtotheload M>1/2 (HM) : the each VSI leg switches a singlepermodulation period and half bridgemodules handle asmaller power share. This modulation scheme is able togeneratethreephasesinusoidalPWMmodulatedvoltagesat any modulation index. It presents the advantage ofprocessinglargepowerlevelsbythree‐phaseVSI.

Figure5:ModulationstrategyLM:(a)timingdiagramforthree‐leveloperation(b)PWMgenerationlogic.

BothLMandHMmodulationpatternsareabletoproduceline to line voltages with five level while all dc sourcessupply positive active power for range 4/(3π)< M<2/3.therefore,anymodulationindexwithinthisrangecanbeachievedandacontrolcanbeusedtoswitchbetweentwomethodswithoutresultinginoscillations.

5. OUTPUTVOLTAGEANALYSIS

The output voltage analysis for four level HC1/2Bemploying proposed modulation and consists inexpressing output phase voltage as function of harmoniccomponentsoffundamentalandcarrierfrequencies.

Theinverterphasevoltagecanbeexpressedby

With and

In (2)variablesand representsangular carrier frequencyandtheangularfundamentalfrequency,respectively,andthe terms and express the amplitude of each harmoniccomponent. The harmonic components are obtained bydoubleFourierintegral

Where is the output phase voltage synthesized by theinverter

6. SIMULATION OF HYBRID MULTILEVELCONVERTER

6.1SIMULATIONBASEDONSPWM

Simulation of hybrid converter for four‐level with IGBTswitches shown in Fig 1.in this simulation model threephase rectifiers are connected with three phasetransformers. The three phase diode bride rectifies thevoltage insecondarysideof transformersandelectrolyticcapacitorssmooththedcvoltagewithlowripple.Thetotalnine half bridge modules implement the four‐levelconverter.Thedcsideinputvoltageis580Vandswitchingfrequency of half bridge converter is 1kHz while outputfundamental frequency is 50Hz. The execution of bothmodulationpatternsLMandHMisperformedinSIMLINK.thesinusoidalreferencesignalsaredisplacedby1200anda zero crossing detector is virtually executed to compare




the polarity of sinusoidal references. The modulation patternsgeneratedbygivenlogicareobservedinFigure6.

Figure6(a):implementedgatesignalpatternsforHMmodulation

Figure6(b):implementedgatesignalpatternforLMmodulation

The command signals generated for both modulationpatterns (HM and LM) based on SPWM technique areshown inFigure6. InFigure6(a) the command signalsfor HM strategy and a modulation index M=0.9 arepresented, while Figure 6(b) shows the gate commandsignalsforLMmodulationformodulationindexM=0.5.

By applying modulation index M=0.9 leads to phasevoltages, i.e., voltages between load terminals andmid‐

point of VSI’s dc‐link, as shown in Figure 7. Figure 7presentsvoltages .it isobservedthatthephasevoltagesclosely follow the simulatedpatterns and aredisplacedbyeachother.ThemeasuredlinevoltageisgiveninFig.9.thewaveformsverifythetheoreticalanalysisofsevenlevel line voltage with low harmonic distortion.




Figure7:simulatedresultsforM=0.9and‐HMmodulation.PhasevoltagesatA,B,Candlinevoltage

Figure8:simulatedresultsforM=0.5and‐LMmodulation.PhasevoltagesatA,B,Candlinevoltage

By applying amodulation indexM=0.5 shows thephasevoltagesinFig.11.itisobservedthatthethreelevelphasevoltage follows the theoretical LM modulation patternwithdcoffsetduetomeasurementfromthephasepointto thecentrepointof theVSI’sdc‐link.the linevoltage isshowninFigure8.

Themodulationindexhasbeenvariedfromclosetounityto close to null to verify active power distributionbetween insulated dc sources and to measure the THDline and phase voltages. The HM modulation patternemployed fromM=1 down to M=0.5, while the LMwasused for lower modulation index values.




Figure9(a):theTHDanalysisforlinevoltageforHM

Figure9(b):TheTHDanalysisforlinevoltageforLM

6.2SIMULATIONBASEDONSVPWM

In the simulation of both HM and LM modulationtechnique themodulatingwave is generated in SVPWMtechnique. The total circuit is as same as SPWMtechnique.thehybridmultilevelinvertercircuitconsistofsixhalfbridgesandonethreephaseVSIdrivenbypatternofSVPWMmodulatingwaves.

The SVPWM technique generated voltage waveformshavinglowTHDascomparedtoSPWM.

Forthemodulation indexM=0.9 leadstophasevoltages,i.e., voltage between load terminals A,B,C andmid‐pointof the VSI,s dc link, as shown in Fig 13.the SVPWMsimulatedHMandLMmodulationpulsesareshowninFig12.the SVPWM HM modulation phase and line voltageshave low THD as compared to LM modulation.




Figure10(a):thesimulatedSVPWMgatesignalpatternforHMmodulationindexM=0.9

Figure10(b):thesimulatedSVPWMgatesignalpatternforLMmodulationindexM=0.5

By applying modulation patterns to the proposedconverter it is observed that four level phase voltagefollowsbytheHMmodulationthreelevelphasevoltagesfollowsbyLMmodulationpatternwithdcoff setdue to

measurementfromphaseterminalstocentrepointoftheVSI’s dc‐link. The line voltage presents seven and fivelevels for HM and LM respectively

Figure11:simulatedresultsforM=0.9and‐HMmodulation.PhasevoltagesatA,B,Candlinevoltage




Figure12:SimulatedresultsforM=0.5and‐LMmodulation.PhasevoltagesatA,B,Candlinevoltage

Figure13(a).theTHDanalysisforlinevoltageforHM

Figure13(b).theTHDanalysisforlinevoltageforLM

Themodulationindexisvariedfromzerotounity.Thetotalharmonicdistortionvariedbasedonmodulationindex .themeasurementresultsaresummarizedasshowninFig.14.




Figure14:THDforlineandphasevoltagesaccordingtomodulationindexM

7. CONCLUSION

The hybridmultilevel converter is able to achieve threelevel and four level operations for HM and LMmodulation. The main advantage of this solution ispossibility of reduction of power rating for insulated dcsources.Afourlevelhybridmodulationschemehasbeenpresented,whichallowsunidirectionalpower flow inalldcsourcesforanymodulationindexandlowerthepowerdemand on insulated dc sources for higher modulationindexes. The theoretical analysis of output voltage hasbeenpresented and verified for LMandHMmodulationof SPWM and SVPWM techniques. The phase and linevoltage’s with low THD’s for SPWM and SVPWMtechniqueshasbeencomparedusingSIMLINK.

REFERENCE

[1] R. H. Baker, “Bridge converter circuit,” U.S. Patent 4270163,May26,1981.

[2]A.Nabae, I.Takahashi,andH.Akagi, “Anewneutral‐point‐clampedPWMinverter,”IEEETrans.Ind.Appl.,vol.IA‐17,no.5,pp.518–523,Sep.1981.

[3] M. Marchesoni, M. Mazzucchelli, and S. Tenconi, “Anon conventional power converter for plasmastabilization,”IEEETrans.PowerElectron.,vol.5,no.2,pp.212–219,Apr.1990.

[4]F.PengandJ.S.Lai,“MultilevelcascadevoltagesourceinverterwithseparateDCsources,”U.S.Patent5642275,Jun.24,1997.

[5] T. A. Meynard, H. Foch, F. Forest, C. Turpin, F.Richardeau, L. Delmas, G. Gateau, and E. Lefeuvre,“Multicellconverters:Derivedtopologies,”IEEETrans.Ind.Electron.,vol.49,no.5,pp.978–987,Oct.2002.

[6] D. A. Ruiz‐Caballero, R. M. Ramos‐Astudillo, S. A.Mussa, and M. L. Heldwein, “Symmetrical hybridmultilevel dc‐ac converters with reduced number ofinsulated dc supplies,” IEEETrans. Ind.Electron.,vol. 57,no.7,pp.2307–2314,Jul.2010.

[7] D. Floricau, G. Gateau, and A. Leredde, “New activestacked NPC multilevel converter: Operation andfeatures,” IEEE Trans. Ind. Electron.,vol. 57, no. 7, pp.2272–2278,Jul.2010.

[8] B.‐S. Suh, G. Sinha, M. D. Manjrekar, and T. A. Lipo,“Multilevelpowerconversion—Anoverviewoftopologiesand modulation strategies,” in Proc. Int. Conf. Optim.Elect.Electron.Equip.,1998,vol.2,pp.AD‐11–AD‐24.

[9]M.Malinowski,K.Gopakumar,J.Rodriguez,andM.A.Perez, “A survey on cascadedmultilevel inverters,” IEEETrans. Ind. Electron., vol. 57, no. 7, pp. 2197–2206, Jul.2010.

[10]J.Rodriguez,S.Bernet,P.K.Steimer,andI.E.Lizama,“A survey on neutral‐point‐clamped inverters,” IEEETrans. Ind. Electron., vol. 57,no. 7, pp. 2219–2230, Jul.2010.

[11]J.Rodriguez,L.G.Franquelo,S.Kouro,J.I.Leon,R.C.Portillo, M. A. M. Prats, and M. A. Perez, “Multilevelconverters: An enabling technology for high‐powerapplications,”Proc. IEEE, vol. 97,no.11, pp.1786–1817,Nov.2009.

[12] S. Mariethoz and A. Rufer, “New configurations forthe three‐phase asymmetrical multilevel inverter,” inConf.Rec. IEEE IASAnnu.Meeting, 2004, vol.2,pp.828–835.

[13]T.A.LipoandM.D.Manjrekar, “Hybrid topology formultilevel power conversion,” Patent W.O. 99/41 828,Aug.19,1999.

[14]P.K.SteimerandM.D.Manjrekar,“Practicalmediumvoltageconvertertopologiesforhighpowerapplications,”in Conf. Rec. IEEE IAS Annu.Meeting, 2001, vol. 3, pp.1723–1730.

[15]K.A.Corzine,“Cascadedmulti‐levelH‐bridgedrive,”U.S.Patent6697271,Feb.24,2004.

[16]P.Lezana,J.Rodriguez,andD.A.Oyarzun,“Cascadedmultilevel inverter with regeneration capability and

0

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200

300

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600

0 0.2 0.4 0.6 0.8 1 1.2

THD[%

]

Modulation index(M)

3‐level 5‐level 7‐level

phase

lineHM modulationLM




reduced number of switches,” IEEETrans. Ind. Electron.vol.55,no.3,pp.1059–1066,Mar.2008.

17] S. R.Minshull, C.M. Bingham,D. A. Stone, andM. P.Foster,“Compensationofnonlinearitiesindiode‐clampedmultilevel converters,” IEEETrans. Ind.Electron., vol. 57,no.8,pp.2651–2658,Aug.2010.

[18]Z.Pan,F.Z.Peng,K.A.Corzine,V.R.Stefanovic,J.M.Leuthen, and S. Gataric, “Voltage balancing control ofdiode‐clamped multilevel rectifier/ inverter systems,”IEEE Trans. Ind. Appl., vol. 41, no. 6, pp. 1698–1706,Nov./Dec.2005

19]P.Barbosa,P.Steimer,J.Steinke,M.Winkelnkemper,and N. Celanovic, “Active‐neutral‐point‐clamped (ANPC)multilevelconvertertechnology,”inProc.Eur.Conf.PowerElectron.Appl.,2005,pp.P.1–P.10.

[20] P. K. Steimer, O. Apeldoorn, B. Odegard, S. Bernet,and T. Bruckner, “Very high power IGCT PEBBtechnology,”inProc.PowerElectron.Spec.Conf.,2005,pp.1–7.

[21] A. L. Batschauer, A. J. Perin, S. A. Mussa, andM. L.Heldwein, “Evaluationof the hybrid four‐level converteremploying half‐bridge modules for two differentmodulation schemes,” in Proc. 25th Annu. IEEE APEC,PalmSprings,CA,2010,pp.909–914.

[22]D.G.HolmesandT.A.Lipo,PulseWidthModulationforPowerConverters.Piscataway,NJ:IEEEPress,2003.

Mr.E.MadhanaGopalwasborninBanaganapalle,Indiain 1989. He received B.Tech (Electrical and ElectronicsEngineering)degree fromJNTUniversity,Ananthapur in2010, and pursuingM.Tech (Power Electronics) in RGMEngineeringCollege(Autonomous),Nandyal.HisareasofinterestsarePowerelectronicsconverters,andElectricalMachines

Mr.MSIVASANKARwasborn in1983.HereceivedhisDiploma in Electrical & Electronics Engineering fromS.B.T.E.T.,Hyderabad in the year 2003.HeGraduated inElectrical&ElectronicsEngineeringfromJ.N.T.U.H.,

Mr. S. Aswak Hussain is a Asst Professor in theDepartmentofElectrical&ElectronicsEngineering,RGMEngineeringCollege(Autonomous),Nandyal.




matlab/simlink model for three phase … · matlab/simlink model for three phase hybrid multilevel...

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