通过220 kV输电线路时船只吊臂顶端三维电场仿真分析

Simulation Analysis of Three-dimensional Electric Field at the Top of Crane Arm on Ship Passing Through 220 kV Transmission Line

船只经过跨河输电线路时引起线路跳闸停运事故时有发生,这严重影响电网的安全可靠运行。为了确保船只安全通过跨航道输电线路,研究船只通过输电线路下方时吊臂顶端电场情况是很有必要的。利用有限元分析软件建立仿真模型,分析不同吊臂形状、吊臂长度和位置的船只通过220 kV输电线路正下方时吊臂顶端电场情况。仿真结果表明,吊臂的存在对船只吊臂顶端电场畸变有一定的影响,吊臂宽度越窄、长度越长、船只距离输电线路弧垂最低点越近,吊臂顶端电场最大值和平均场强越大。研究结果对校核跨航道输电线路放电的安全距离裕度具有指导意义。

Ships pass through cross-river transmission lines can cause line tripping and outage events,which seriously affects safe and reliable operation of power grid.In order to ensure the safety of transmission lines and ships,it is necessary to study electric field at the top of crane arm on ship passing under transmission line.Using finite element analysis software,a simulation model was established to analyze electric field distribution at the top of crane arms with different shapes,lengths and positions passed directly under 220 kV transmission line.The results show that the ship crane arm under transmission line has a certain influence on electric field distortion at arm top.Narrower arm width,larger arm length,and smaller distance of crane arm top-line arc bottom all contribute to larger maximum and average values of electric field intensity at the top of crane arm.This study may be useful for determining safety margin against ship-induced undesired discharge of cross-river transmission lines.