500kV同塔双回线路典型杆塔进入等电位方式电场仿真计算

Simulation analysis of electric field on entering equal potential of 500kV double circuit transmission line towers for live working

500kV同塔双回线路相导线布置紧凑,作业人员进出等电位的电场环境更为严峻.以典型同塔双回线路的直线塔和耐张塔为对象,运用CAD软件建立杆塔、金具、绝缘子串等构件精细三维模型,运用有限元软件对导线、跳线进行参数化建模,采用谐响应分析法仿真计算了杆塔附近的空间电场分布,分析带电作业人员沿不同路径进入等电位的电场环境和人体进入强场区的体表场强.结果表明：两种塔型中,从塔身沿水平或斜角路径接近相导线过程的电场变化规律大体一致,越接近导线,场强增加越快.耐张塔跳线对路径上和空间的电场分布存在影响.人体进入强电场区后,手尖和腿部前端场强较高,面部最大场强大于240kV/m,建议加戴屏蔽面罩以满足安全要求.

In the double-circuit transmission lines,the compact arrangement of phase conductors makes it more difficult for live working workers entering equal potential.This paper takes a tangent tower and a tension tower with double circuit lines as research objects.Using three-dimensional CAD software to build the refined model of tower,insulator strings,fitting.The conductor and jumper were established based on parametric modeling by finite element software.Adopting harmonic response analysis,the electric field distribution around the tower is obtained;the electric field intensity along different routes when entering equal potential from tower and on different parts of body surface are analyzed.Simulation results show that the jumper affects the electric field distribution on the path and in the space of tension tower;the characteristic of electric field intensity on horizontal path is similar to the slant path for these two towers;the closer to the wire,the electric field strength increases more quickly.In the strong electric field region,high field strength occurs at the worker＇s hand and the front end of the leg;the maximum electric field strength on the face exceeds 240 kV/m,which concluded that it＇s recommended to wear a screening helmet to ensure the security of live working.