基于特征参量Kh10的复合绝缘子污闪试验

Pollution Flashover for Composite Insulators Based on Characteristic Parameter Kh10

该文基于特征参量Kh10研究复合绝缘子污闪试验。以真型复合绝缘子为研究对象,测量试品受潮期间泄漏电流及特征参量Kh10,并尝试通过Kh10表征污层受潮后的综合状态。试验发现:对于尺寸较大的人工污秽复合绝缘子,测量Kh10时应尽量保证测量区域电场分布均匀,且测量电压不宜过高,应避免剧烈放电导致污层受潮,状态突变。在此基础上,该文改进复合绝缘子受潮试验方法,通过测量个别伞裙受潮期间Kh10,以局部区域受潮状态表征整支绝缘子受潮情况,并将污层受潮状态与绝缘子闪络电压建立联系。研究认为,对于尺寸较大的真型复合绝缘子,特征参量Kh10能有效表征污层综合状态,对于同型号复合绝缘子,若闪络试验前Kh10值趋同,则试品闪络电压接近,此结论不受污层污秽度、污秽成分、憎水性能差异影响。该研究有利于改进复合绝缘子人工污秽试验方法,也可用于优化自然污秽绝缘子状态监测。

This paper focuses on pollution flashover test for composite insulators based on the characteristic parameter Kh10.The leakage current and Kh10 of insulators were measured during wetting.The parameter Kh10 was used to characterize the wetting state of pollution layer.It is found that measuring Kh10 on artificial polluted insulators with large size should keep electric field on the measuring area as uniform as possible.The measurement voltage for Kh10 should not be too high,and the obvious change of polluted layer affected by strong discharge during wetting should be avoided.Method for the wetting test of composite insulators was improved.By measuring Kh10 on certain sheds,the surface state was used to represent the wetting state of the entire insulator.The correlation between wetting state of polluted layer and flashover voltage of insulators was studied.Test results show that characteristic parameter Kh10 can also effectively represent the wetting state of polluted layer for real insulators with large size.For the same type composite insulator,the flashover voltage is close if the Kh10 value is the same before flashover test.And this conclusion is not affected by the difference in pollution grade,pollution composition and hydrophobicity.This study not only improves artificial pollution test method of composite insulators,but also optimizes the condition monitoring method of natural polluted composite insulators.