绝缘子表面污层位置对流注放电的影响

Influence of Insulator Surface Contamination Position on Streamer Discharge

为研究流注的产生和传播对污闪过程的影响因素,利用3电极结构,通过光电倍增管得到的光脉冲信号来检测流注在极板间的传播过程,得到了流注的传播概率曲线和传播速度。通过比较测量结果,对绝缘子表面不同位置涂覆污秽层时的传播特性进行研究。研究表明:污秽带的位置对流注的稳定传播电场影响很大,污秽带涂覆在绝缘子表面上、中、下3个位置时,流注放电的稳定传播电场分别为503、598、646 kV/m;外加电场相同时,流注的传播速度随着污秽带向下移动而不断减小。仿真计算的结果表明:污秽带涂覆不同位置时绝缘子表面电场分布畸变很明显,污秽带位置不同,电场畸变也有所不同,在污层区域平均电场有明显减小。污层影响绝缘子表面的电场分布,导致流注传播特性产生变化。

In order to study the streamer formation and influential factors of streamer propagation tO pollution flashover, through light pulse signals obtained by photomultipliers, we measured the propagation of streamers between two plane electrodes in a three-electrode structure, and then calculated the streamer＇s probability curves and velocities. Eventually, by comparing the measurement results, we studied the characteristics of streamer propagation on insulator surface with contamination brushed on different positions. The results show that, the position of contamination greatly influences the field strength of stably propagating streamer, Est： it is 503, 598 and 646 kV/m when the contamination is on the upper, middle and lower position of insulator, respectively. The velocity of streamer decreases with the contaminated position moving downwardly. The results of simulation show that the distribution of electric field on the surface of insulator dis- torts obviously. While this distortion varies with contaminated position, and the average electric field of contaminated part decreases significantly. It is concluded that contamination changes the characteristics of streamer propagation though in- fluencing the electric field distribution on insulator surface.