10kV配电线路的雷电感应过电压特性  

Characteristics of Lightning Induced Overvoltage of 10 kV Distribution Lines

作　　者：王希[1] 王顺超[1] 何金良[1] 曾嵘[1] 

机构地区：[1]清华大学电机工程与应用电子技术系电力系统及发电设备控制和仿真国家重点实验室,北京100084

出　　处：《高电压技术》2011年第3期599-605,共7页High Voltage Engineering

基　　金：国家自然科学基金重点项目(50737001);国家重点基础研究发展计划(973计划)(2009CB724504)~~

摘　　要：架空配电线路绝缘水平低,直击雷及雷电感应过电压导致的雷击闪络事故率很高,为了重点研究考虑大地有限电导率后配电线路雷电感应过电压的波形特性和统计特性,采用时域有限差分(the finite difference-timedomain,FDTD)算法求解多导体传输线方程,在算法中考虑了绝缘子的闪络过程以及大地电导率对传输线的影响,给出了线路在几种典型雷击情况(直击雷和雷电感应)下,不同大地电导率时配电线路上的感应过电压发展过程及分布特性。分析结果表明,不考虑大地电导率与考虑大地电导率的计算结果相差很大。还分析了雷电流幅值、上升时间、雷击点与线路距离等因素对雷电感应过电压水平的影响。针对不同大地电导率情况下配电线路的感应过电压进行了统计分析,给出了考虑直击雷及不考虑直击雷两种情况下线路最大感应过电压概率分布、绝缘闪络率以及闪络次数。The insulation level of overhead distribution lines is relatively low with high flashover rate.An improved algorithm is proposed by applying FDTD algorithm to solve the multi-conductor transmission line equation and taking insulator model and soil conductivity into account.We focus on the waveform and statistical characteristics of lightning surge voltage of 10 kV overhead distribution lines under different ground conductivities,and present the development process of induced voltages for several typical lightning strikes which include direct and indirect lightning strikes.The analysis indicates that the calculation results depend sharply on whether considering ground conductivity.Moreover,we analyze the influences of peak value and the rise time of lightning current,the distance between lightning striking point and distribution line,and other factors on the induced voltage level.The statistical evaluation results of the maximum lightning-induced voltage are presented when considering indirect and direct lightning strikes under different ground conductivities,the results include the probability distribution of peak value of induced voltage and flashover rate per 100 km per year.

关 键 词：10KV线路 时域有限差分(FDTD) 配电线路 大地电导率 感应过电压概率分布 雷电 

分 类 号：TM863[电气工程—高电压与绝缘技术]