染污绝缘子放电发展区段与污闪预警的实验研究

污闪是污秽放电的极端结果，针对绝缘子泄漏电流与污秽放电之间的紧密联系，通过实验室反复试验，研究泄漏电流的特性，目的是提取污闪预警的特征量以防止污闪的发生。该文从泄漏电流有效值、泄漏电流波形以及泄漏电流功率谱图3个角度入手，提出污秽放电发展过程可以划分为3区段，即安全区、预报区和危险区。同时指明了泄漏电流时域和功率谱域的区段分界线，为进一步研究污秽放电预警提供了有效帮助。研究表明泄漏电流有效值变化，泄漏电流波形发展变化以及功率谱最大谱峰值曲线增长速率k的大小，可以为污闪预警提供更明确的理论指导。试验证明此划分有利于污闪预警系统更清晰地建立，有利于工程人员的实际操作。

Experimental Research on Discharge Development Zones of Contamination Insulators and Contamination Flashover Prewarning

Contamination flashover is the extreme result of contamination discharge of insulators. Because of the close relationship between leakage current and contamination discharge of insulators, it is significant to research the characteristics of leakage current during contamination discharge of insulators. The rules of leakage current were studied by taking a number of experiments in the laboratory, which aimed at obtaining the characteristic parameters to prevent the contamination flashover of insulators. This paper studied the effective value, the waveform and the power spectrum of leakage current. It is found that the whole course of contamination discharge can be divided into three zones, namely safety zone, forecast zone and danger zone. Furthermore, the dividing lines of the three zones in time domain and in power spectrum domain are pointed out definitely, which is helpful to further study the contamination discharge prewarning. It has been also showed by the tests that the effective value changes, the waveform changes and the rising velocity of maximal peak value curve of power spectrum of leakage current i.e. k can provide much more clearer theoretical guidance for the contamination flashover prewarning. The division of three zones is more effective to establish the prewarning system of contamination flashover, and is in much favor to practical application.