简介:Summary1.Thereare12powersystemsincluding5regionalpowersystemswithover1000MWofcapacityeach.In1989CentralandEastChinapowersystemswereinterconnectedbya±500kVHVDCLine.2.Thehierarchicalcontrolorganizationcanbedividedinto5levels,i.e.NCC,6RCCs,25PCCs,250DCCsandmorethan2000CCCs.3.AllcontrolcenterswillbeequippedwithSCADAandEMSinthenearfuture.4.Chinapowersystemhasalarge,dedicatedcommunicationnetworkofitsown.
简介:Inourearlierpaper,powersystemstabilizers(PSSs)aredesignedforanine-machinesystem,anewpole-placementtech-niqueisdevelopedforthedesign,andparticipationfactorsareusedtodecidehowmanystabilizersarerequiredandwheretheyshallbe.Eachmachinebeingrepresentedbyalow-orderlinearmodel,thereissomereservationoftheresults.Inthispaper,extensivetransientsimulationsareperformedandeachmachineisrepresentedbyahigh-ordernonlinearmodel.Coherentgroupsarefound.Aweightedspeeddeviationindex(SDI)isdefinedtofindoutthemostunstablemachinesinthesystem.PSSsaredesignedafterthedecisionsofPSSnumberandsites.Transientsimulationsarecarriedoutagainfortheclosed-loopsystem.Asystemstabilityindex(SSI)isusedtoevaluatethestabilityoftheclosed-loopsystem.ItisfoundthatthreePSSsaresufficienttoensurethestabilityofthenine-machinesystem.
简介:ThePowerSystemDepartment(PSD)isthelargestpro-fessionalresearchanddevelopmentorganizationoncomprehensivepowersystemplanning,engineeringandoperationoftheElectricPowerResearchInstitute(EPRI)oftheMinistryofEnergy.TheactiveRD&EofPSDarecomposedofthefollowingfivemajorareas.Powersystemanalysis,softwaredevelopment&application,automaticdevices,DCtransmission,generation&transmissioncommission,modernlaboratoriesforRD&Eandelectricalappara-
简介:1.GeneralReviewTherapiddevelopmentofextrahighvoltagetransmissionlinesandpowersystemsraisedseriousstabilityproblems.Becauseofthelongdistancetransmissionofpowerandrelativeweaksystemconfiguration,stabilitybecamethemostimportantandseriousproblems.Therisksintermsofdisturbancecausingsubsequentsysteminstabilitycouldbeveryhighandtheresultsoffrequencyandvoltagecollapsemaycausecatastrophicresults.
简介:1.IntroductionTheNortheastPowerSystemisoneofthefourbulkpowersystemsinChina,whichcoverstheprovincesofLiaoning,Jilin,HeilongjiangandasmallpartofInnerMongolia.Thetotalinstalledcapacityin1990was21,300MWandthepeakdemandwas13,600MW.TheControlCenterisinShenyang.Thedispatchingautomationsystemwhichismainlycomposedofadualcomputersystem(2XVAX785)wasinstalledandputintooperationin1988.Theplanto
简介:Guangdong,acoastalprovinceinsouthChina,hadverypoorfoundationofindustryinthepast.AftertheestablishmentofPeople’sRepublicofChinain1949,undertheleadershipandunifiedplanningofthecentralgovernment,economyconstructionofbothindustryandagriculturehavebeenboostedandhencetheprovicialelectricpowerindustryhavedevelopedaccord-ingly.Especiallysince1979,theimplementationofreformationand
简介:Toanalyzetheinfluenceof±400kVQinghai-TibetHVDCtransmissionsystemontransmissionlineprotectionsinQinghaiACpowersystem,aclosed-loopsimulationsystemwasconstructedbycombingHyperSimsystemwithHVDCcontrolprotectiondevices.Variousfaultsondouble-circuit750kVandmulticircuit330kVACtransmissionlinesinQinghaipowersystemweresimulated.TheimpedancecharacteristicsandharmoniccomponentsatQinghaisideofQing-TibetDCtransmissionlinewereanalyzed.TheharmonicproportioninvoltagesandcurrentswerestudiedforfaultsthattookplaceatdifferentlocationsneartheDCsystem.TheinflenceofQing-TibetDCsystemonthedirectionalcomponentsofprotections,differentialprotectionsanddistanceprotectionsofACtransmissionlineswasdiscussedanddrewtheconclusionsthattheDCsytemhadlittleinfluenceondifferentialprotections,whilehadgreatinflenceondirectionalcomponentsanddistanceprotection.TheconclusionscanprovidereferenceforstudyingtheinteractionbetweenACandDCsystems.
简介:1.GeneralreviewThefirst330kVtransmissionlineinNorthwestChinafromLiujiaxiaHydroPowerStationthroughQinanSubstationtoTangyuSubstationwascommissionedin1972.Intheseventies,accompany-ingthecommissioningofHanchengandQinlingThermalPowerPlantsinShaanxiProvince,the330kVtransmissionlinesfrom
简介:TopicsofcurrentinterestInthelastissueofthisjournal“ELECTRICITY,CSEE”areportwaspresentedontheInternationalConferenceonPowerSystemTech-nology’91wherespecialistsfrom15countriesweregatheredtogethertodiscusstopicsofcommoninterest.Severaloutstandingproblemsdeservespecialreport.Forinstance,thegreenhouseproblemwasreportedinthisissueunderthecolumnofpowerandenvironment.Theoperator’strainingsimulatorisreportedinaspecialarticleinthisissue.Sinceaseriesoflargescaleblackoutsoccurredinseveralcountries,particularlythe1977NewYorkCityblackout,peoplerealizedthatoperatorsinthemodemfullycomputerizedandautomatedcontrolcenterneedconstantpracticeonasimulator,sothattheycanbefullypreparedtohandlesuddenattacksofseveredisturbances.Thecurrentprob-lemsandviewsfromseveralcountriestakingpartinthepaneldiscussionwerereportedinthisissue.Somenewtechniquesattractingmuchattentionfromresearchersinthefieldofpowersystemtechnology,suchasfuzzysystems,ExpertSystems,ArtificialNeuralNetworksandPetriNetswerediscussedtoquitesomeextentinthisconference.Theyarealsoreportedinthisissue.Morespecialsubjectswillbereportedinlaterissues.(Ed.)
简介:BenefitsofSeriesCompensationinLongTransmissionSystemX.Z.Lei,D.PovhSIMENSAG,PowertransmissionandDistributionGermany,D91050.P.O...
简介:AsreportedfromafieldseminaronMJAon-linecoalcompositiondetectionsystem,NDRChasrankedtheMJAsystemwiththekeyandspecialprojectsofciviliannon-powernucleartechnologyindustrialization.MJAdevicedevelopedindependentlybyNanjingDaluZhongdianTechnologyCo.,Ltd.isthefirstfullcoalflow,all-elementandall-indextypeofon-linedetectionsystem.Itwassuccessfullyusedforincomingcoaldetectionofpowerplants.
简介:ThispaperputsforwardanewfaultdiagnosismodelbasedonPetrinet.Inthisnewfaultdiagnosismethod,anassociatedtreeisfirstdefinedtodescribethelogicaccordingtotheprotectionsandcircuitbreakers.AfterthataPetrinetdiagnosismodelcomesintobeingandtheprecisediagnosisofpowergridelementscanberealizedatthesametime.Thesimulationresultsgiveninthispaperillustratethatthisfaultdiagnosismethodcanmakearapiddiagnosisincomplexfaultsituationandgiveaccurateresultstopowergridfaultdiagnosis.
简介:Comparedwithtraditionalsynchronousgenerators,windturbinegeneratorsaredifferentinelectricitygenerationprinciples,controlmodesandintegrationtopologies,whichmakestheirfaultcharacteristicschangealot.This,consequently,bringschallengesregardingthebehaviorofprotectionsforwindfarmcollectorsystems.Inthispaper,basedonapracticalwindfarm,configurationandsettingofrelayprotectionsforsuchacollectorsystemisanalyzedanddeterminedsystematicallyinconsiderationoftheselectivityandsensitivityoftheprotections.Resultsshowthatmisoperationofovercurrentrelayandzerosequenceovercurrentrelayofthenon-faultcollectorlineoccurs,andbusdifferentialrelayofcollectorbuscannotremovethesingle-phase-to-groundfault.Inordertosolvetheproblems,anovelsubstation-areaprotectionforcollectorsystemisproposedanditsoperationmechanismisdiscussed.
简介:Ⅰ.ThesituationofgeographyandeconomyinCentralChinaregionTheCentralChinaregioncoversHenan,Hubei,HunanandJiangxifourprovinces.Itstotalareaamountsto730,000squarekilometerswithapopulationofabout238millionandpossessculti-vablelandof16.82millionhectares.Thisregionisoneoftheim-portantproductivebasesofgrains,cottonandedibleoil.
简介:Theboilerisoneofthekeypartsofpowerstation.Monitoringtheoperationoftheboilerautomatically,continuouslyandaccuratelyisveryimportant.Incaseofmalfunctions,anexpertsystemmightbehelpfultofindthesourcesoffaults,andthereafterwillassisttheoperatortoactcorrectlyandtopreventthefaultfromfurtherdevelopment.Inthispaper,asimulationstudyofanexpertsystem,whichcandiagnosetherunningfaultsofboilersystem,isconducted.Shallowanddeeptwo-layerknowledgebasestructureisusedinthistwolayersofknowledgebase.So.thiskindofexpertsystemcanovercomethedisadvantagesoftheoldtypesofexpertsystems,whichareonlyabletodealwithexperiencerulesbase.Asimulatorofpowerboilerisusedfortheresearchonfaultdiagnoseexpertsystem.Thisboilersimulatorgivesallnecessaryinformationforthediagnosis.Theknowledgebaseofexpertsystemisbuiltinhierarchies,sothespeedofreasoningmaybeinvreased.Afterthereasoningthesys
简介:Beganfromearly1992,ChongqingPowerSupplyBureauhadspent3andhalfyearstobuildupapowerloadmanagementsystemconsistingofImasterstation,6relaystations,1280terminalsandthedistributedmonitoringdevice.Thissystemdistributesinthehillyandmountainousareaswheregeographicallycomplicatedandtheloadwidelyscatters,itcansuperviseabout72%loadandcurtailmorethan15%loadwhen
简介:As"congestioncosts"ofcoaltransportationarefairlyhigh,asoundcomparisonofeconomicefficiencybetweencoaltransportationandpowertransmissionshouldtake"congestioncosts"ofcoaltransportationintoaccount.Otherwise,itcannottrulyreflectpowertransmission’sefficiencyadvantage.Inadditiontoraisingrailwaycapacity,theChinesegovernmentshouldalsoincreasepowertransmissiontorelievethetransportationpressureonrailwaytocutdown"congestioncosts."