变电站内短路电流分流系数实测和分析-李谦

377Vol.37No.720137PowerSystemTechnologyJul.20131000-3673201307-2060-06TM645.2A470·401712115100802()100084MeasurementandAnalysisonShort-CircuitCurrentShuntCoefficientInsideSubstationLIQian1,JIANGYukuan2,XIAOLeishi1(1.ElectricPowerResearchInstituteofGuangdongPowerGridCompany,Guangzhou510080,GuangdongProvince,China;2.StateKeyLabofControlandSimulationofPowerSystemsandGenerationEquipments(Dept.ofElectricalEngineering,TsinghuaUniversity),HaidianDistrict,Beijing100084,China)ABSTRACT:Whenasingle-phaseshort-circuitfaultoccursinsideasubstation,it’sthecurrentdiffusingintogroundthatactuallycausesthesecurityproblemratherthanthefaultcurrent,andthemorethecurrentdiffusesintoground,themoreseriousthesafetyproblemwillbe.Shuntcoefficientcharacterizestheshuntabilityofgroundinggridoroverheadgroundwirestofaultcurrent,soitcanbeutilizedtoanalyzethedistributionofshort-circuitcurrent.Thecurrentdistributionofsingle-phasegroundingfaultinsideacertainsubstationismeasuredandtheshuntcoefficientsareobtainedbycalculation,andthemeasuredresultsarecomparedwithsimulationresults.Comparisonshowsthatthemeasureddataconformstosimulationresults,andtheshuntcoefficientofgroundwiresisbig.Simulationcanbeusedtoanalyzetheshuntcoefficientofgroundwiresinsidesubstationswhereshort-circuitfaultoccurs,andtheresultsareavailableforreferencetoengineeringpractice.MainfactorsandinfluencingregularitiesrelatedtoshuntcoefficientsofgroundwiresareanalyzedbyPSCAD,anditisshownthattheshuntcoefficientofgroundwireswillbebiggerwhilegroundingresistanceisbiggerortherearefeweroutlines.KEYWORDS:substation;short-circuitfault;short-circuitcurrent;groundwire;shuntcoefficient;groundingresistance0[1-5]3GB/T500652011R2000/IG[6]IG[7-8]2[9-10][11-19][20-22]DOI:10.13335/j.1000-3673.pst.2013.07.0453772061PSCAD11[23]I0Iw1Iw2INIgI0Iw11Iw12INIw2Iw21Iw22I0IgIw11[23]Fig.1Currentdistributionwhileshortcircuitoccurredinsideasubstation[23]12IEEE[2]GB/T500652011Ks1Ks2s1w0N/()K=|III|(1)s2g0N/()K=|III|(2)Iws1s21K+K=(3)IgKs12220kV2.1220kV220kV26134m222011010kV3220kV2AB110kV1C10kV220kVA31(opticalfibercompositeoverheadgroundwireOPGW)2BA110kVC2OPGW4OPGW1OPGWOPGW220kV1M2012A220kVA42864ACTA2BBA#2#1A2012428614286242862M1MA428642Fig.2Electricalwiringdiagramoftheequipmentinshort-circuitfaultexperiment2062Vol.37No.7A110kVABB2M201242862012A2.2431301515300.000.030.060.090.12t/sI/kAAOPGWBOPGWC1OPGWC2OPGW3Fig.3Waveformsofshort-circuitcurrentandgroundwires’current1Tab.1Parametersofthecurrentwaveforms/kA/(°)21.4620.00AOPGW5.21319.08BOPGW5.39025.83C1OPGW1.26113.50C2OPGW1.24113.502.3I0AOPGWIw1BOPGWIw2C1OPGWIw3C2OPGWIw4IN=0A4ws1w010N/0.5915ii=IK=||=|II|=II(4)4w1ii=I59.15%(220kV)(110kV)433.1PSCAD0.6512PSCAD42Tab.2Parametersoflinesinasubstation/(Ω/km)/mmOPGWOPGW/(Ω/km)OPGW/mmALGJ-400/520.07213.8OPGW-2S2/360.3658.0LBGJ-100-27ACBLGJ-400/520.07213.8OPGW-2S2/360.3658.0LBGJ-100-27ACCLGJ-300/400.09213.4OPGW-2S1/240.3896.9—/(Ω/km)/mm/m/Ω/m/km/ΩA0.6406.548.05380230.5B0.6406.553.05400170.5C——30.3540070.53.24533772063ABCABCABCABCABCGGIG1IIG2IG3IG4ABCABCG1G20.6514PSCADFig.4SimulationmodelofPSCAD301.5201.5601.600101030kAt/sI0IG2IG3IG4IG15Fig.5Waveformsofshort-circuitcurrentandgroundwires’currentbysimulation3Tab.3Comparisonbetweensimulationandmeasurement/kA/%21.46222.4774.73AOPGW5.2134.8906.20BOPGW5.3905.4511.11C1OPGW1.2611.1727.22C2OPGW1.2411.1715.720.5920.5743.04=(||/)100%7.22%44.11[22]500kV220kV4.2PSCAD1220110kV50Hz220kmRt103Rg4.30.51[24]4220kV110kV220kV54Tab.4Parametersofthetransformerforsimulation/MVA/kWYNd11300208/%/kW/%0.3850135Tab.5Influenceonshuntcoefficientbydifferentfaultpositions(I0IN)/kAIw/kAKs1/%220kV14.485.3637.00110kV10.273.9138.1221.657.9836.87I0IN110kVI0IN2064Vol.37No.74.4110kV14220kV66Tab.6InfluenceonshuntcoefficientbydifferentgroundingresistanceofsubstationRg/(I0IN)/kAIw/kAKs1/%0.110.273.7736.680.210.293.7836.800.310.293.8237.090.410.283.8637.530.510.273.9138.120.610.253.9838.850.710.214.0539.690.810.184.1340.630.910.134.2241.661.010.084.3142.782.09.375.2756.253.08.556.0570.69I0IN4.5110kV4220kV0.5220kV110kV78I0IN220kV110kV110kV220kV7110kVTab.7Influenceofthenumberoflinesat110kV’ssideonshuntcoefficientoffaultcurrent220kV110kV(I0IN)/kAIw/kAKs1/%1110.273.9138.121315.984.2926.871521.444.5221.073120.544.0119.523325.724.4217.183530.574.6715.288220kVTab.8Influenceofthenumberoflinesat220kV’ssideonshuntcoefficientoffaultcurrent220kV110kV(I0IN)/kAIw/kAKs1/%1110.273.9138.123120.544.0119.525128.273.8913.751315.984.2926.873325.724.4217.185332.964.3213.094.61232521.462kA59.15%PSCAD123[1][M]20071-5[2]SubstationsCommitteeoftheIEEEPowerEngineeringSocietyIEEEguideforsafetyofACsubstationgroundings[S]NewYorkIEEE2000[3][J]201034(3)201-204YangLinWuGuangningLiJianmingFieldtestofimpulse3772065characteristicofgroundmesh[J]PowerSystemTechnology201034(3)201-204(inChinese)[4][J]201236(5)161-165YangLinWuGuangningCaoXiaobinAtransientmodelingapproachofsubstationgroundinggrid[J]PowerSystemTechnology201236(5)161-165(inChinese)[5][J]200832(22)98-102ChangYongWangMingleiXuChongwuetalEquilibriumoptimizationofpotentialdiffere