Damping of Low-Frequency Interarea Oscillations

FromtheSelectedWorksofA.R.MessinaJanuary2003DampingofLow-FrequencyInterareaOscillationsUsingHVDCModulationandSVCVoltageSupportContactAuthorStartYourOwnSelectedWorksNotifyMeofNewWorkAvailableat:(4)#4046ElectricPowerComponentsandSystems,31:389–402,2003Copyrightc
2003Taylor&Francis1532-5008/03$12.00+.00DOI:10.1080/15325000390112251DampingofLow-FrequencyInterareaOscillationsUsingHVDCModulationandSVCVoltageSupportA.R.MESSINAJ.ARROYON.EVARISTOI.CASTILLOTGraduatePrograminElectricalEngineeringCinvestav,IPNP.O.Box31-438Guadalajara,Jal.44550MexicoThispaperdiscussestheresultsofpreliminarystudiesconductedtoexaminetheapplicabilityofhigh-voltagedirectcurrent(HVDC)technologyandstaticVolt-AmpReactive(VAR)compensationtoaiddampingoflow-frequencyin-terareaoscillationsintheMexicaninterconnectedsystem(MIS).ThestudyofinterareaoscillationsandthedesignofcontrolsisdoneusingmodalanalysisofalinearizedAC/DCstatespacemodelofthepowersystemataparticularoperatingpoint.TheutilizedmethodologyistestedonaplanningmodeloftheMISthatincludesaproposedHVDCtransmissionsystemembeddedinanACnetworkinwhichseveralSVCsareusedfordynamicvoltagesupport.Detailedtime-domainanalysesareperformedtocomplementknowledgeontheeffectofFACTStechnologyonsystemtransientbehavior.Keywordsinterareaoscillations,HVDCtransmission,SVC1.IntroductionHigh-voltagedirectcurrent(HVDC)transmissionsystemsofferapowerfulalter-nativetoincreasethestabilityofapowersystemaswellastoimprovesystemoperatingflexibility.TheapplicationofHVDCtechnologyisofspecialinteresttotransfermassiveamountsofremotehydroelectricpoweroverlargedistances[1,2].Incomplexinterconnectedsystems,however,theapplicationofthistechnologytoachievethemosteffectivestabilizationofcriticalinterareamodesrequirestheproperassessmentofmanyinteractingfactorssuchasthelocationoftheDClink,thecontrolconfiguration,andtheuseofmodulationcontrols.Manuscriptreceivedinfinalformon4March2002.ThefinancialsupportoftheMexicanCouncilforScienceandTechnologyunderGrant31840-Aisacknowledged.AddresscorrespondencetoA.R.Messina.E-mail:[e-mail]licationofHVDCtechnologyandStaticVARCompensator(SVC)modulationtoaiddampingoflow-frequencyinterareaoscil-lationsinpowersystemsofessentiallylongitudinalstructure.AplanningmodeloftheMexicaninterconnectedsystem(MIS)isadoptedtoassesstheapplicabil-ityofHVDCtransmissiontoenhancetransfercapabilitiesaswellastodeterminepotentialadverseinteractionswithothercontrollers.Theanalysisoflow-frequencyoscillationsandthedevelopmentofremedialmeasuresbasedonFlexibleacTransmissionSystems(FACTS)technologyisdoneinthemodaldomainusingalinearizedstatespacerepresentationofthepowersystem.Time-domainsimulationsarethenperformedtovalidatetheaccuracyofthedevelopedmodels.Systemstudiesfocusontheanalysisandcontroloftwolightlydampedinterareamodesassociatedwiththeinteractionofgeographicallywidespreadmachines.Studyresultsincludetheidentificationofinterareamodesthataremorecon-trollablebytheproposedHVDClink,andtheuseofSVCvoltagesupportandmodulationcontrolstoenhancethedampingofcriticalsystemmodes.TheeffectsofHVDCmodulationandSVCvoltagesupportonsystemdampingarediscussedforvariouscontrolconfigurationsandinputsignals.Itisshownthatthecoordi-natedapplicationofHVDCtransmissionandSVCvoltagesupportcaneffectivelycontributetothesimultaneousstabilizationofcriticalinterareamodes.2.DescriptionoftheStudySystem2.1.GeneralStructureoftheMISThebulkMexicaninterconnectedsystemcomprisesahuge400/230kVtransmissionsystemstretchingfromtheborderwithCentralAmericatoitsinterconnectionwiththeUnitedStates.Aone-linediagramofthestudysystemisgiveninFigure1showingmajorexistingSVCsandthegeographicallocationoftheproposedHVDCsystem.TheMISconsistsofsixareasdesignatedasthenorth(N),northeastern(NE),western(W),central(C),southeastern(SE),andpeninsularsystems.Systemstud-iesinthisresearcharebasedonareduced-orderequivalentmodeloftheMISthatincludesthedetailedrepresentationof49machines,191buses,183transmissionlines,and5SVCs.Loadsarerepresentedas70%constantcurrentloadand30%constantimpedancecharacteristicsforbothactiveandreactivepower.InthismodelnointerconnectionswiththenorthwesternandpeninsularsystemsoftheMexicansystemareconsidered.ThissystemisconsideredarealistictestsystemtoevaluatetheperformanceoftheproposedHVDCcontrolscheme.2.2.TheSoutheasternSystemThesoutheasternnetworkoftheMISwassingledouttoinvestigatethecapabilityofHVDCtransmissionofintroducingdampingtocriticalinterareamodes.Figure2depictsthegeneralstructureofthe400/230kVSEnetwork,showingthemainma-chinesandtransmissionfacilities.TheSEnetworkconstitutesatypicallongitudinalsystem,characterizedbysparse,longtransmissionpaths,andremotegenerationsources[3,4].HydroelectricpoweristransmittedtotheMexicoCitymetropolitanareaoveradistanceofabout900kmbya400kVnetworkofessentiallylongitudinalDampingofLow-FrequencyInterareaOscillations391Figure1.AC/DCsystemconfiguration.structure.Dynamicvoltagesupportandseriescapacitivecompensationarepro-videdatseveralkeylocationstoall