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重庆大学硕士学位论文动态电压恢复器的补偿策略研究与仿真分析姓名：余小闯申请学位级别：硕士专业：电气工程指导教师：唐治德2010-05I,,(DVR)DVRDVRDVRDVRdqabdqSPWMDVRDVRDVRDVRDVRMatlab7.0HDVRDVRDVRIIABSTRACTWiththedevelopmentofmodernscienceandtechnologyandtheautomationofproductionrising,kindsofsophisticatedelectricalequipmentsarewidelyusedforelectricityandpowerconsumersdemandhigherqualitypowersupply.Themostcommonpowerqualityproblemisvoltagesag.Dynamicvoltagerestorer(DVR)isoneofthemosteffectivetoolstosolvevoltagesag.Asanewpowerqualitycontroldevice,DVRcanmoveinafewmilliseconds.DVRhasanunparalleledadvantageintheeliminationofvoltagefluctuationandflicker,andsolvingthephasevoltageasymmetryandshort-termpowerinterruption.Aswithgooddynamicperformanceandhighcost,DVRhasbecomethefirstchoicewhenpoweruserssolvetheproblemsofdynamicpowerquality,andespeciallythemosteconomicalandeffectiveelectricaldeviceforsolvingthevoltagesagproblem.Inthispaper,workingprincipleofanypartsofDVRmaincircuittopologyisdemonstratedcomprehensively.Compensationstrategy,detectionalgorithmsandcontrolmethodsfortheDVRarestudied.Thecascadedinverterischoosedasthemaincircuittopologyandsupercapacitorastheenergystoragedevice,whichdonotneedextraenergystoragedeviceandseriestransformer,andhelpcutcosts,reduceareaandimprovesystemreliability.Chooseimprovedsingle-phasedqdetectionalgorithmasthevoltagesagdetectionalgorithmwhichchangesingle-phaseinstantaneousvoltagefromtheabstationarycoordinatesystemtransformationtothedqrotatingcoordinatesystemandcangreatlyreducethecomputation.SPWMischoosedasthecontroltechnologyofinverterwhichenablestwo-waytransmissionofenergy;Inaddition,SPWMcanusetoovercomeharmonicpollutiongeneratedbyuncontrolledrectifieronthenetworkside.Threebasiccompensationstrategiesaredescribedindetailandtheyarepre-sagcompensation,in-phasecompensationandminimum-powercompensation.Theyarecomparedbyphasordiagramanalysis.Therelationshipbetweeninjectedactiveandloadpowerfactorarederivedaftertheanalysisofminimum-powercompensationforDVR.Basedonthis,theimprovedminimum-powercompensationstrategyisproposed.ThetopologicalstructureofDVRconnectedtothesystemisimprovedinthiswaythatathyristor-switchedinductorisaddedacrosstheloadwhichisbecarriedoutwhenDVRiscompensatingsags.Minimumpowerconsumptionisachievedwithdeliberatereductionofthepowerfactorbythethyristor-switchedinductor.Finally,minimumpowercompensationissimulatedinMatlab7.0andthefeasibilityofthedesignschemeisverifiedbysimulationresultswhichshowthattheproposedmethodreducesthepowerinjection,enlargethevoltagesagrangeofpurereactivecompensationandbeingabletomitigatetheseverersagwithlongerdurationIIIKeywordsPowerquality,Voltagesag,DynamicvoltagerestorerDVR,Compensationstrategy1111.1[1];[1-3]9035~40200060[4-5]260[4-5]IEC(1000-2-2/4)[6](IEEE)11:interruptions0.1p.u.4instantaneous0.530momentary303temporary31sustained,60frequencydeviationsag10%0.5~10.1p.u.0.9p.u.swells10%0.5~11.1p.u.~1.8p.u.transientvoltagefluctuation0.9p.u.~1.1p.u.12flickernotche0.5harmonic33interharmonicfractionalharmonic(overvoltage)1min1.1p.u.~1.2p.u.?undervoltage1min0.8p.u.~0.9p.u.1[7]30min30min1min10s02468101.1Fig.1.1Frequencyofoccurrenceofpowersupplyqualityandpowerqualityproblems(relativeratio)1.1[7]131.2[8]1.2.1IEEE10%~90%10[9]1.2.2(/sagrefMFUU=)refUsagU(90%)1.2.3[1011]3~670%,,14()1.2.4;;Siemens1.1Siemens[12]1.1(100%)Table1.1Theimpactofvoltagesagontheequipments(100%ofratedvoltageforthestandard)80%85%(PLC)10%15;50%PLC;1/090%90%2380%(VSD)70%6VSD90%350%1;70%60%121.1151.2.5“(CUSTOMPOWER)”[13]UPS(UninterruptiblePowerSupply)UPS92%~97%STS(StaticTransferSwitch)()STSSTS(STATCOM)(SFCL)/(S/N)SFCLDVR(DynamicVoltageRestorer)DVRUPSSFCL1.3(DynamicVoltageRestorerDVR)16(DVR)DVR[13]1996(Westinghouse)(Wescon)DVR19968Duke12.47kVDVR2MVA[14]ABB22kV/4MVADVR[15]IEEE[16]ABBDVR(22.5MVA)2000ABBIGCTDVRIGCTGTOIGBTSIEMENS2MVA4MVADVRDVRTMPM8MVA4050%0.32MVA4MVADVRTMPMDVRTMPMDawsonCreek25kV500kVADVRCutler-Hammer1998DVR17DVRDVRDVR,,DVRDVRDVRDVRDVR1.4DVRDVRDVRDVRdqDVRdqDVR(SPWM)DVRDVRDVRMatlab7.0SimulinkDVRDVR2DVR82DVRDVR2.1DVRDVR2.1DVRFig.2.1ThedeploymentdiagramofDVRinthepowersystem2.12.1DVRDVR()DVR35kV5DVR2.2DVRDVR2.2DVR2DVR9UiUlodUsTsL1L2T1T22.2DVRFig.2.2ThebasicstructureofDVRandthesinglelinediagramconnectedtothesystem2.2.1DVRDVRDVR1/22.2.2DVR2.32DVR10UdvrT1T22.3Fig.2.3TheschematicdiagramoftransformercouplingmodeDVRDVR6kV2.42DVR11T12.4Fig.2.4Theschematicdiagramofcapacitancecouplingmode2.2.3DVRDVR2.5ABCABCT1T22.5Fig.2.5Theschematicdiagramoffilter’sinstallationpositionABC2DVR122.2.4DVRDVRDVRDVRDVR5091000-350°~750°[21]2.32.3.1DVRDVR[22][23]2N+1(N)[24-26]IGBTDVRH2DVR13DVR2.3.2DVRDVRDVRHDVR2.6UdvrCfLfT1T22.6DVRFig.2.6ThesinglelinediagramofcascadedmultilevelInvertersDVRDVR2.4DVR2.4.12.7DVRDVR2DVR14T1T22.7Fig.2.7Thestructurediagramofuncontrolledrectifiermodel2.8BoostDVRT1T22.8Fig.2.8ThestructurediagramofboostconvertmodelDVR2.2.22.4.22DVR15T2T1UdvrCfLfdcscdcscdcscdcscdcscdcsc2.9Fig.2.9Theprinciplestructurediagramofsupercapacitoron-linealternatecharging[26]2.9IGBT3%500VBuckDVR500VBoostDVR5%2DVR162.5DVRDVRDVRDVR3DVR173DVRDVRDVRDVR3.1[27-30]n2ii=11U=uN∑(3.1)Niu[29]()