自然积污绝缘子污闪电压变异系数的统计分析

Statistical Analysis on Variation Coefficient of Flashover Voltage of Naturally Contaminated Insulators

统计分析了均匀升压法得到的自然积污绝缘子污闪电压变异系数的分布规律,并与人工污闪电压变异系数进行对比分析。结果表明:采用均匀升压法得到的绝缘子自然污闪电压变异系数置信上限的最大值为0.310 1;变异系数近似服从正态分布,期望值为7.45%,其95%置信区间的上限为8.14%,与采用升降法得到的自然污闪电压变异系数的期望值基本一致;总体上,自然污闪电压的分散性大于人工污闪电压的分散性。

This paper performs a statistical analysis on distribution rules of variation coefficient of flashover voltage of naturally contaminated insulators obtained by average set-up method and comparatively analyzes the distribution rules and those of variation coefficient of artificial contamination flashover voltage. The results show that the upper confidence limits of variation coefficient of natural pollution flashover voltages , which are obtained with the average step-up method, have a maximum of 0.3101, and the variation coefficients approx-imately comply with normal distribution , with the expectation value of 7.45%, and its upper limit is 8.14%in 95% confidence interval, which is almost consistent with the results obtained with up-and-down method. In general, the dispersity of natural contamination flashover voltage is greater than that of artificial contamina-tion flashover voltage.