电力系统暂态分析.ppt
上传人:qw****27 上传时间:2024-09-12 格式:PPT 页数:49 大小:4.2MB 金币:15 举报 版权申诉
预览加载中,请您耐心等待几秒...

电力系统暂态分析.ppt

电力系统暂态分析.ppt

预览

免费试读已结束,剩余 39 页请下载文档后查看

15 金币

下载此文档

如果您无法下载资料,请参考说明:

1、部分资料下载需要金币,请确保您的账户上有足够的金币

2、已购买过的文档,再次下载不重复扣费

3、资料包下载后请先用软件解压,在使用对应软件打开

NegativeSide:DirectMethodIntroductionsClassificationsAnAnalogyOfRollingBallModelApplicationtopowersysytem:ThebasisfortheapplicationoftheTEF(TransientEnergyFunction)methodtotheanalysisofpowersystemstabilityisconceptuallysimilartothatforaballrollinginabowl.Initiallythesystemisoperatingatastableequilibriumpoint.Ifafaultoccurs,theequilibriumisdisturbedandthesynchronousmachinesaccelerate.Thepowersystemgainskineticandpotentialenergyduringfault-onperiodandthesystemmovesawayfromtheSEP.ThestepsforLyapunovfunctionmethod:1)Defineenergyfunction;2)Determinecriticalenergy;3)Comparingtheenergyatfaultclearingandcriticalenergytojudgethesystemisstableornot.DefinitionOfTheTransientEnergyFunctionStabilityRegionAndPhasePlaneDiagramIntheabovefigure,eachlotus(1~5)isanequalenergycurve.Thetotalenergyincreasesfrominsidertooutsider,untilthecorrespondingmaximumsealedcurvetounstableequilibriumpointandreachescriticalenergy.Thiscurveiscalledpolarcircle,theinsideisstableregion.Thus,wegetcriticalenergyTheProcedureOfLyapunovFunctionMethodPotentialEnergyBoundarySurface(PEBS)ApproachPrincipleStepsAssessIndividualMachineEnergyFunction(单机能量法)ReferenceFirstPresentedByMichelInHisThesis:powersystemtransientstabilityusingindividualmachineenergyfunction,IEEETrans.Oncircuitsandsystems,Vol.3,No.5,May1983,pp266~276TwoProblems:Situationsareoftenencounteredinpowersystemswherecomplex“modes”ofinstabilityarise,makingitdifficulttodetermine(withconfidence)therelevantu.e.pSignificantportionsofthesystemtransientenergydonotcontributetosystemseparation;henceitshouldbecorrectedforintransientstabilityassessment.CriticalGroupOfMachinesOverallsystemenergyfunctionConclusionsAccuratelypredicts:a)whichmachineslosesynchronism,b)criticalclearingtimeAgoodestimateofisobtainedfromthesustainedfaulttrajectory.Provideslessconservativestabilityresults.ExtendedEqual-areaCriterionTimeDomainSimulationMethodAllYourWorksAreBasedOnMyTheory!!!SEEACTomapthetwo-machinesystemintotheOMIBsystem,wefurthermoredotheRMtransform:Applica