表面电荷积聚对冲击电压下绝缘子沿面放电的影响

绝缘子的表面缺陷会导致表面电荷积聚，使绝缘子表面的电场发生畸变，影响冲击电压下绝缘子的沿面放电。研究了表面电荷对绝缘子沿面放电进程的影响，发现表面电荷积聚可以降低绝缘子沿面放电的起始电压。外施冲击电压的极性与绝缘子表面电荷极性是否相同会影响绝缘子的电晕起始时刻、由流注向先导的转变时间间隔和流注电晕电流。表面电荷对GIS支撑绝缘子的50％冲击闪络电压和伏秒特性也有一定的影响。

Effect of Surface Electric Charge Accumulation on Creeping Discharge of Insulator Under Impulse Voltage

The surface defect of insulator can cause surface electric charge accumulation, which makes the electric field distortion of insulator surface, and effects creeping discharge of insulator under impulse voltage. This paper studies the effects of surface electric charge on creeping discharge process of insulator, and discovers that surface electric charge accumulation can reduce the initial voltage of insulator creeping discharge. The polarity of impulse voltage and the polarity of insulator surface electric charge can affect the corona initial time of insulator, the change time - interval and the corona current. Surface electric charge can also affect the 50 % impulse flashover voltage and volt - second characteristic of CIS support insulator.