电力系统低频振荡扰动谐振机理研究

华中科技大学硕士学位论文电力系统低频振荡扰动谐振机理研究姓名：刘志炜申请学位级别：硕士专业：电力系统及其自动化指导教师：文劲宇20080606IPhillips-HeffronPRBSsinc0.1~2.5Hz42IIAbstractWithChina’spowersysteminterconnectionandthedevelopmentoftheelectricitymarket,securityincidentsofSmallSignalStabilityinpowersystemoccurmoreandmoreanditbringsaboutalotofhiddendangersinsafeoperationofthepowersystem.Whenthegeneratorsarelackindampingtorque,therotorsamongthesegeneratorsareeasilytohaverelativeswings,leadingtodurativelow-frequencyoscillations(LFO)ontransmissionlines.ThisLFOisatypicalphenomenonaboutdeficiencyofsmallsignalstabilitymargin.Moreover,someunknownlow-frequencyoscillationphenomenaoftenhappenintheprocessofthepowersystemoperation.Thispaperpresentsadisturbanceresonancemechanismforpowersystemlow-frequencyoscillation.Thispaperatfirstintroducestheclassicsecond-ordermodelofnegativedampingmechanismofpowersystem,andonthebasisofit,theresonancemechanismbothinthe2ndordergeneratormodelandPhillips-Heffronmodelisderivedindetail.Itindicatesthatwhenthefrequencyofsmalllow-frequencydisturbancesignalimposingontheshaftofgeneratingunits,regulationsystemandexcitationsystemisconsistentwithorclosetothepowersystemnaturaloscillationfrequency,thepowersystemwillamplifythemagnitudeofdisturbanceandtransittothestatusoflow-frequencyoscillationsinresonanceform.Disturbanceresonancemechanismisanextensionoftheresonancemechanism.Disturbancescanbefoundeverywhereinpowersystem.LFOinpowersystemwillbecausedinthecasethatthesinusoidalcomponentofdisturbancesignalisclosedtosystemnaturalfrequency.Furthermore,basedondisturbanceresonancemechanism,wedesignedbothPRBSandsincfunctiondisturbance-signalpowersources.Accordingtocharacteristicsofthesetwosignals,wesetthefrequencyofthesetwosourcesattherangeof0.1~2.5Hzandcalculatedtheirmaximumpoweroutputs.Weintheorydeducedthatbothtwodisturbancesourceshavethefeatureofsmall-storagebuthigh-poweroutput.Intheend,weappliedthesetwodisturbancesourcestoSingleMachine-InfiniteBusSystemaswellasFour-generatortwo-areaSystemtoinspectandverifydisturbanceresonancemechanisminpowersystemlow-frequencyoscillationsviaaddingdifferentdisturbingcapacitiesandIIIplacingdiversedisturbing-locationsinsimulation.Wealsothoughtovertheinfluenceoflaggingeffectoftheenergystoragedeviceatthesametimeanditprovidesreferencefordynamicsimulationexperimentsinthenearfuture.Keywords:low-frequencyoscillation;smallsignalstability;resonancemechanism;disturbanceresonancemechanism;disturbancepowersource:______::111.11.1.112[1]0.12.5HzInterareamodes0.10.8HzLocalmodes0.82.5Hz[2-3]1.1.2[4-9]21996810[10-14]WSCCWesternSystemsCoordinatingCouncil0.20.3Hz1976WSCC[15]1996810146493500kVBigEddy-OstranderJohnDay-MarionMarion-Lane500KV350Keeler-Allston1300MW1542375230kVRose-LexingtonMcNary154737McNary8WSCC0.28Hz0.266Hz154750154805McNaryAGCAutomaticGenerationControl0.242Hz-2.661548051548202PDCIPacificHVDCIntertie0.217Hz-7.62154942154954[15-16]ElectricPowerResearchInstituteEPRIWSCC[15-16]HVDCAGC3[17-19]19835211351180MW350MW230MW250MW223MW5100MW10MW40MW580MW198423132kV66kV±50±80MW5101.7200MW198424400345kV1950MW±70MW1.1Hz1519988220kV40MW1HzPSSPowerSystemStabilizer220kV2220kV41.21.2.11)1969F.Demello[20]2)[21]3)[22]4)80;[23]5)5[24](1)(2)(3)1.2.26QRAnalysisofEssentiallySpontaneousOscillationsinPowerSystemsAESOPS[25]SelectiveModalAnalysisSMA[26]SSMatrixMethod[27]LinearFractionalTransform[28]Arnoldi[29]Cayley[30]“”Nyquist[31]71996810WSCCAGC19881994WSCCSystemOscillationsWorkGroupsSOWG0.7Hz0.3Hz[31][32][33][34]81.31)Phillips-Heffron2)PRBSsinc0.12.5Hz3)PRBSsinc4)SMESSMES5)PRBS922.1(PSS)SVCPSS2.20.1~2.5Hz2.2.1'dXEmPDDQ10(1)1medMPPDdtddtωωδω=−−−=−(2-1)0cosmdEUMPDdtXddtωδδωδω∑∆=∆−∆−∆∆=∆(2-2)0cosEUKXδ∑=...0MDKδδδ∆+∆+∆=(2-3)D=01,2nKpjjMω=±=±(2-4)δ∆nω0D≠21,242DjDMKpjMα−±−==±Ω(2-5)nωΩ≠2DMα−=D0a0D0a05~12MS=0cos1EUδ≈0.2~10X∑=314/bradsω=,max0.05nω≈2.5HzX∑0.2~0.7HzX∑1Hz112.2.2Phillips-Heffron[2]''''''0()(1)1dqqqqddqdfqfqdddmeVXIVEXIdETEEEEXXIdtdMPPDdtddtωωδω==−=−=−+−=−−−=−(2-6)'''()eqqdqdqPEIXXII=−−fEmP2-11EEKTP+fErefVtV−+2-11fEtEEKVTP∆=−∆+(2-7)22tdqVVV=+(2-6)0mP∆=12''0dqfqeTpEEEMpPDpωωδω∆=∆−∆∆=−∆−∆∆=∆(2-8)'''0000''()()()()eqqqqdqdqdqqqdddPEIEIXXIIIIEEXXI∆=∆+∆−−∆+∆∆=∆+−∆(2-9)'12''43eqqqqPkkEEkEkEδ∆=∆+∆∆=∆+∆(2-10)00''01''0002'sincos0())10dqqdqqqqdddUUXXXXXXIkIEXXIkXXδδ++−=++−+(2-11)'3'1dddXXkXX−=++(2-12)'40'()sindddUkXXXXδ=−+(2-13)EffEtTpEEKV∆=−∆−∆(2-14)'005601()tddqqqtVVVVVkkEVδ∆=∆+∆=∆+∆(2-15)0'00'050600'0sincos010qddqtqqtqdtVUUXXXXXVkVkVVXXXVδδ−++=++(2-16)Phiilips-Heffron13()GOVGp1MpD1K3K0'1dTp1p∑∑2K6K∑4K()EGp5K∑δ∆ω∆mP∆++++−−'qE∆−−−−2-2Phillips-Heffron12'34'56'eeqqqqttqPPkkEEEkkEVVkkEδδδ∂∂==∂∂∂∂==∂∂∂∂==∂∂(2-17)(1)'0fE∆=2-2...0eMDPδδ∆+∆+∆=(2-18)241'30()edKKPKKTpδ∆=−∆+(2-19)eePTω=0eeePTTωω∆=∆+∆0ω∆≈01ω=eePT∆=∆241'30edKKTKKTpδδ∆=∆−∆(2-20)δ∆.δω∆=∆ω∆90o10K14234,,0KKK'0dT24'30dKKKTpδ∆+eT∆δω∆−∆2-3ω∆δ∆eDeT∆eK1Kδ∆24'30dKKKTp+02-3eT∆eeeTKDδω∆=∆+∆(2-18)''52'306(1)()EeEdEKKKTTpKTpKKδ−∆=∆+++(2-21)eT∆ω∆eD“4K”(2)4K4K''''1,eeeeTTTTKδ∆=∆+∆∆=∆''52'306(1)(