自然积污绝缘子的污闪电压和泄漏电流特性试验研究

Experimental Research on Pollution Flashover Voltage and Leakage Current Characteristics of Naturally Polluted Insulators

以浙江电网自然积污FC70P/146、XWP2-7绝缘子为对象,对自然积污绝缘子的污闪电压和泄漏电流特性进行了试验研究;提出了考虑污秽折算系数的自然积污绝缘子外绝缘特性试验研究方法,采用数据拟合方法得到了自然积污绝缘子表面等值盐密、灰密及上下表面积污不均匀性对污闪电压及泄漏电流的影响规律。结果表明:对于自然积污FC70P/146和XWP2-7绝缘子,污闪电压的不均匀度影响特征系数N分别为0.128 5和0.095 9,要小于人工污闪电压的N值。对于FC70P/146绝缘子,泄漏电流的平均等值盐密影响特征指数a和不均匀度影响特征系数N分别为0.757 2和0.218 8;对于XWP2-7绝缘子,a和N分别为0.454 7和0.180 8。相对而言,FC70P/146绝缘子的a、N值要大于XWP2-7绝缘子。

Taking naturally polluted FC 70P/146 and XWP2-7 insulators for overhead transmission lines in Zhejiang power grid for research objects, experimental research on pollution flashover voltage and leakage current characteristics of naturally polluted insulators is performed. The method for experimental research on external insulation characteristics of naturally polluted insulators, in which the conversion coefficient of pollution is considered, is proposed, and the influencing regularities of equivalent salt deposit density（ESDD） and equivalent non-soluble material deposit density（NSDD） of naturally polluted insulators as well as the non-uniformity of dirt retention between upper and lower surfaces of polluted insulators on pollution flashover voltage and leakage current are obtained by data fitting. Research results show that as for naturally polluted FC 70P/146 and XWP2-7 insulators, the characteristic coefficients N characterizing the influence of pollution flashover voltage non-uniformity are 0.128 5 and 0.095 9 respectively, and they are less than the value of N characterizing the influence of artificial pollution flashover voltage. For FC 70P/146 insulator, the influencing characteristic index of average ESDD of leakage current a and the characteristic coefficient N characterizing the influence of non-uniformity are 0.757 2 and 0.218 8 respectively; for XWP2-7 insulator the value of a and N are 0.454 7 and 0.180 8 respectively. Relatively speaking, the values of a and N of FC 70P/146 insulator are higher than those of XWP2-7 insulator.