交联聚乙烯绝缘高压直流电缆电场分布计算

18520145ElectricMachinesandControlVol.18No.5May2014123221．3158002．1500803．276800:为设计交联聚乙烯(XLPE)绝缘高压直流电缆的结构，在实验基础上总结出进口高压直流电缆XLPE绝缘材料的电导特性方程，利用COMSOLMultiphysics软件通过电场和热场耦合仿真计算了电缆在不同负荷下的电场分布。研究表明，在电场强度较低和较高时，进口高压直流电缆XLPE绝缘材料的电导率随温度变化明显，电场强度变化几乎不对其产生影响;在某一电场强度范围内，温度和电场强度的改变均会使XLPE的电导率发生明显变化，该场强范围随温度而变化;所设计高压直流电缆在两种敷设环境下100%负荷时电场分布均匀;在电缆传输电流较大时，电缆XLPE绝缘内的温度梯度增大，电缆绝缘外表面处电场强度最大。基于有限元法的多物理场耦合仿真计算是研究XLPE绝缘高压直流电缆电场分布的有效手段。:高压直流电缆;交联聚乙烯;有限元;模拟仿真;电场TM247A1007－449X201405－0019－05SimulationofelectricalfielddistributionofXLPEinsulatedHVDCcableYEXin-hong1HANBao-zhong2HUANGQing-qiang3ZHAOHong2YANGJia-ming21．NingboDongfangCableLimitedbyShareLtdNingbo315800China2．KeyLaboratoryofEngineeringDielectricandItsApplicationMinistryofEducationSchoolofElectricalandElectronicEngineeringHarbinUniversityofScienceandTechnologyHarbin150040China3．ＲizhaoPowerSupplyCorporationofShandongElectricPowerCorporationＲizhao276800ChinaAbstractInordertodesignthestructureofcross-linkedpolyethyleneXLPEinsulatedhighvoltagedi-rectcurrentHVDCcabletheelectricallyconductivecharacteristicequationofimportedXLPEinsula-tionmaterialsforHVDCcableisderivedbasedonexperimentalresultsandtheelectricalfielddistribu-tionofcableunderdifferentloadsiscalculatedthroughelectro-thermalfiledcouplingsimulationbyusingtheCOMSOLMultiphysicssoftware．TheresearchresultsshowthattheelectricalconductivityofimportedXLPEinsulationmaterialsforHVDCcableissensitivetotemperaturevariationandfreetochangeinelec-tricalfieldstrengthwhentheelectricalfieldstrengthislowerorhigher．Thechangeintemperatureande-lectricalfiledstrengthcanleadtoremarkablechangeofelectricalconductivityofXLPEinsomerangeofelectricalfieldstrengththatdependsontemperature．TheelectricalfielddistributioninsidethedesignedHVDCcableisuniformunder100%ofloadattwolayingconditions．AstransportcurrentishigherthetemperaturegradientinsideHVDCinsulationcableincreasesandtheelectricalfieldstrengthofoutsidesurfaceofinsulationcableismaximal．Thesefindingsindicatethatthemulti-physicalfieldcouplingsimu-lationbasedonthefiniteelementmethodisaneffectivewaytoinvestigatetheelectricalfielddistributionofXLPEinsulatedHVDCcable．Keywordshighvoltagedirectcurrentcablecross-linkedpolyethylenefiniteelementsimulatione-lectricalfiled2013－05－21:国家自然科学基金重点项目(51337002);国家863计划项目课题(2013AA050102);哈尔滨市科技创新人才研究专项资金项目(优秀学科带头人)(2012ＲFXXG079):叶信红(1968—)，男，高级工程师，研究方向为高压电缆结构设计与制造;韩宝忠(1970—)，男，教授，博士生导师，研究方向为高性能聚合物电介质材料;黄庆强(1988—)，男，助理工程师，研究方向为高电压与绝缘技术;赵洪(1955—)，男，教授，博士生导师，研究方向为纳米复合电介质理论及测试技术;杨佳明(1984—)，男，博士研究生，讲师，研究方向为纳米复合电介质理论及测试技术。:韩宝忠0、、、1－2。。XLPE、、、3－6。XLPE2100km320kV。XLPE3、。XLPE20205000km7。XLPEXLPE、、XLPE。20XLPEXLPE。XLPECOMSOLMultiphysics250kVXLPE。1XLPEXLPE8E=U0rlnＲrc1ErV/mU0VrcmＲm。1。XLPE22XLPE9γ=γ0eaθ2E=U0BrB－1ＲB－rBc3B=aθc－θslnＲrc。4γ00℃XLPES/mγθ℃XLPES/maθc℃θs℃。3B＜1。XLPE3。XLPE。22.11GT－7014－P10CW2175℃15MPa230min310℃/min50℃4100mm、0.2mm5DMJ－45050mm624h。02182.21。屏蔽箱皮安表直流电源1Fig．1Diagramofstructureoftestingsystemforelectricalconductivityofsamples30℃、40℃、50℃、600℃70℃10h30℃、40℃、50℃、60℃70℃。33.1XLPE1lnγ=aθ+lnγ0。5lnγθ。0.22mmXLPE2kV5kV2。2kV5kVe-28e-29e-30e-31e-32e-33e-34电导率（S·m-1）3040506070温度/℃2XLPEFig．2ＲelationshipcurvebetweentemperatureandelectricalconductivityofXLPEunderconstantvoltage2lnγθ2a。3.2XLPE10－11γ=AEβ6Aβ。β=0β＞0β。6lgγ=lgA+βlgE。77lgγlgElgγlgEβA。XLPE3。30℃40℃50℃60℃70℃10-1310-1410-1510-16电导率（S·m-1）0.1110电场强度（kV·mm-1）3XLPEFig．3ＲelationshipcurvebetweenelectricalconductivityofXLPEandelectricalfieldstrength3XLPE0.4～30kV/mmXLPE6。3.3XLPE23XLPEXLPEXLPE。XLPEXLPEXLPE。3.13.2XLPEγ=CθeaθEβθ。823XLPE4kV/mmXLPE4kV/mm。125130≤θ＜40γ=1.38×10－28.74×e0.21θ×E1.694000≤E＜3.55×107×0.99θγ=10－16.52+0.084θ10E≥3.55×107×0.99θ。240≤θ＜60γ=5.08×10－28.09×e0.14θ×E1.6114000≤E＜1.64×108×0.95θγ=10－14.24+0.027θ12E≥1.64×108×0.95θ。360≤θ≤70γ=8.80×10－51.56×e1.03θ×E5.2－0.06θ134000≤E＜1.14×1036.74×0.37θ15.2－0.06θγ=10－13.82+0.02θ14E≥1.14×1036.74×0.37θ15.2－0.06θ。4XLPE250kVXLPE4。1-线芯；2-绕包半导电双面阻水带；3-导体屏蔽；4-XLPE绝缘；5-绝缘屏蔽；6-缓冲阻水带；7-金属护套；8-防腐层；9-PE护套；10-垫层；11-铠装；12-外护套。1234567891011124250kVXLPEFig．4DiagramofstructureofXLPEinsulatedhigh-voltageDCcableof250kV70℃1640A1400A。XLPE1600mm20.3mm1.7mm18mm1.2mm1mm2.7mm。COMSOLMultiphysics100%70℃56。0.050.040.030.020.010-0.01-0.02-0.03-0.0414.1741514.814.614.414.21413.813.613.413.2132.507%6×10-13-0.04-0.0200.020.04（a）1%640%A-0.04-0.0200.020.04（b）1%400%A14.7041514.814.614.414.21413.813.613.413.2132.262×10-130.050.040.030.020.010-0.01-0.02-0.03-0.045XLPEFig．5DistributionofelectricalfieldinsideXLPEinsulatedhigh-voltageDCcable14.1514.114.051413.9513.913.8513.813.7513.713.6513.613.55电场强度/（kV·mm-1）0.0280.030.0320.0340.0360.0380.040.0420.044与线芯中心轴距离/m（a）1%640%A14.714.614.514.414.314.214.11413.913.813.713.613.513.413.3电场强度/（kV·mm-1）0.0280.030.0320.0340.0360.0380.040.0420.044与线芯中心轴距离/m（b）1%400%A6Fig．6DistributionofelectricalfieldalongcableradiusdirectioninsideXLPEinsulation2218560.9450.980。1640A1400A1。1640A1400A10.55℃7.74℃。51XLPE。2XLPE。3XLPE。4XLPE。1．J．201232137－12．WENJialiangWUＲuiPENGChangetal．AnalysisofDCGridProspectsinChinaJ．ProceedingsoftheCSEE201232137－12．2SOODVK．－M．20081－10．3WENDTV．C//2011201124－32．4JACOB