半导电层电性参数对站用支柱绝缘子电场分布的影响

Effect of electrical parameters of semi-conductive layer on electric field distribution of post insulator used in substation

本文利用COMSOL计算和分析了半导电层电性参数对站用支柱绝缘子表面电场分布的影响。结果表明:半导电层对潮湿生成的水珠、湿污和干污引起的最大电场均有不同程度的削弱作用,湿污最为显著,电场降幅为41.58%;在高压端涂覆半导电层对电场的改善效果显著,与不涂覆半导电层相比,表面最大电场最大降幅为14.5%;高、低压端涂覆各自最佳相对介电常数的半导电层,其电场改善的综合均衡性较好;在正常瓷件电性参数范围内,半导电层最佳电性参数具有通用性,高压端最佳半导电层相对介电常数为22,低压端最佳半导电层相对介电常数为12,此外,高、低压端半导电层的电阻率至少分别大于1×10^(7)Ω·m和6×10^(7)Ω·m,其最大电场才将小于不涂覆半导电层的情况。

In this paper,the effect of electrical parameters of the semi-conductive layer on the surface electric field distribution of post insulator used in substation was calculated and analyzed by COMSOL.The results show that the semiconductive layer can weaken the maximum electric field caused by water droplets,wet pollution,and dry pollution to different degrees,and the wet pollution is the most significant,with the electric field decreasing amplitude of 41.58%.Coating semi-conductive layer at the high voltage terminal has a significant improvement effect on the electric field,and the maximum decreasing amplitude of surface maximum electric field is 14.5%compared with not coating semi-conductive layer.When the high and low voltage terminals are coated by semi-conductive layer with the best relative dielectric constant,the comprehensive balance of electric field improvement is better.In the normal range of porcelain electrical parameters,the optimal electrical parameters of semi-conductive layer are universal,the relative dielectric constant of the optimal semiconductive layer at high voltage terminal is 22,and the relative dielectric constant of that at low voltage terminal is 12.In addition,the resistivity of the semi-conductive layer at high and low voltage terminals should be at least greater than 1×10^(7)Ω·m and 6×10^(7)Ω·m,respectively,and the maximum electric field will be less than the case without semi-conductive layer.