220kV交联聚乙烯电力电缆接地电流的计算与应用  

Calculation and Application of 220 kV Crosslinked Polyethylene Power Cable Grounding Current

作　　者：杜伯学[1] 李忠磊[1] 张锴[1,2] 王立[1,3] 

机构地区：[1]天津大学电气与自动化工程学院,天津300072 [2]浙江省电力建设监理公司,杭州310009 [3]北京市电力公司,北京100102

出　　处：《高电压技术》2013年第5期1034-1039,共6页High Voltage Engineering

基　　金：国家自然科学基金(51277131)~~

摘　　要：单芯高压电缆金属护套接地电流过大会导致其护套上产生大量附加损耗,降低电缆载流量,缩短电缆使用寿命。为此,针对交叉互联接地方式下的220kV交联聚乙烯(XLPE)单芯高压电缆工程,建立了单芯电缆交叉互联接地方式下接地电流的数学计算模型,分析了单芯高压电缆接地电流与其排列方式及其负载电流之间的关系,并编制了相应的计算程序。结果表明该计算程序能准确得到实际电流值。在此基础上,提出了基于接地电流的220kV XLPE电力电缆运行状态的辅助分析:通过分析接地电流计算值与测量值之间差值的大小,可以判断电缆接地系统是否存在缺陷或故障隐患。若2者相差较小,则表明系统运行正常;若2者差值>10%,则可判定系统存在缺陷或出现故障。研究结果为高压电缆运行监测提供了理论依据。Excessive grounding current on metal sheath of single-core high-voltage cable will bring massive additional loss to the cable,which reduces the cable’s current-carrying capacity and safe operation lifetime.Therefore,aiming at 220 kV crosslinked polyethylene（XLPE） single-core high-voltage cables in cross-bonding grounding mode,we established a mathematical model of grounding current was founded.Thereby,we analyzed the relationship among the grounding current on metal sheath and the arrangement of cable and the load current,then we developed a relevant calculation program to calculate the grounding current.The calculation results proved that the program was competent to reflect actual grounding current.Furthermore,we further analyzed the operating state of 220 kV XLPE power cables,and compared the calculative value and the measured value to judge whether a grounding system has deficiencies or faults.It is proposed that,if the difference between the two values is no more than 10%,the system operates normally,otherwise,the system has a defect or a fault.The proposed results provide a certain theoretical basis for monitoring high-voltage cable operation.

关 键 词：单芯高压电力电缆 交联聚乙烯 交叉互联 接地电流 数学模型 计算程序 运行状态评估 

分 类 号：TM744[电气工程—电力系统及自动化]