基于多层磁场的大长段电缆护套感应电压精确计算方法  

Accurate Calculation Method for Sheath Induced Voltage over Long Cable Segments Based on Multilayer Electromagnetic Field

作　　者：赵轩 张蕾 黄磊[2] 高飞 张瑞永[3] 刘江涛 Zhao Xuan;Zhang Lei;Huang Lei;Gao Fei;Zhang Ruiyong;Liu Jiangtao(State Grid Jiangsu Electric Power Co.Nanjing Power Supply Co.,Nanjing Jiangsu 210019,China;College of Electrical Engineering,Southeast University,Nanjing Jiangsu 210096,China;Jiangsu Electric Power Design Institute,Nanjing Jiangsu 211102,China)

机构地区：[1]国网江苏省电力公司南京供电公司,江苏南京210019 [2]东南大学电气工程学院,江苏南京210096 [3]江苏省电力设计院,江苏南京211102

出　　处：《电气自动化》2020年第2期76-79,112,共5页Electrical Automation

基　　金：江苏省电力公司科技项目(J2018068)。

摘　　要：电缆分段段长的大小主要取决于金属护套感应电压的大小,最大值不能超过国标300 V,因此金属护套感应电压的精确计算是确定段长的关键。基于电磁场理论,建立三相电缆空间磁场分布的数学模型,并计及电缆的结构参数,计算空间某一位置的金属护套感应电压。使用仿真软件进行验证,并与现有简化公式法计算结果对比表明,考虑电缆结构参数的电磁场求解法的计算结果与仿真结果更加接近,尤其是对于线径较小容量较低的电缆,为大长段电缆段长的选择提供理论指导作用。The length of cable segments depends largely on the level of metal sheath inducted voltage,which can not exceed 300 V according to the national standard.Therefore,accurate calculation of metal sheath induced voltage is the key to the determination of the segment length.Based on the theory of electromagnetic field,a mathematical model was established for spatial electromagnetic field distribution of the three-phase cable.Furthermore,under consideration of structural parameters of the cable,metal sheath induced voltage was calculated at a certain spatial location.Simulation software was used for verification.Comparison with the calculation result of the existing method of simplified formula indicated that the calculation results from the electromagnetic field solution considering structural parameters of the cable was closer to that of the simulation,especially for those cables with small diameter and low capacity.The proposed approach could provide theoretical guidance to the selection of long cable segments.

关 键 词：高压电缆 多层电磁场 金属护套感应电压 集肤效应 

分 类 号：TM744[电气工程—电力系统及自动化]