覆冰程度对瓷和玻璃绝缘子直流覆冰闪络特性的影响

Influence of Iced Level of Porcelain and Glass Insulators on DC Flashover Performance

在人工气候室内模拟覆冰气象条件,对2种同吨位的瓷绝缘子XZP-210和玻璃绝缘子LXZP-210进行了覆冰直流闪络实验研究。分析实验结果得出2种绝缘子在不同覆冰程度和不同污秽下覆冰直流闪络特性,即最低冰闪电压值Ufmin随覆冰厚度的增加而呈幂函数下降关系,与覆冰质量m呈负指数函数关系,与电导率γ20呈负幂函数关系;导出旋转监测铜管覆冰厚度d和绝缘子串覆冰质量m两种表征覆冰程度参量的等价性关系式d=De-gW;最后提出了绝缘子串直流最低冰闪电压Ufmin的一般式Ufmin=Eγ2-0md-be-fW。

The DC flashover performances under the different climate conditions simulated in the artificial climate chamber were experimentally investigated on two kinds of ice-coated insulators with the same tonnage,porcelain XZP-210 insulators and glass LXZP-210 insulators.Based on the DC flashover test results in the artificial climate chamber,the effect of ice＇s extent and pollution on the DC flashover performance of iced-insulators was analyzed.The results show that the minimum DC flashover voltages（U_fmin） will decline as icing thickness,icing weight or conductivity increases,U_fmin forms an exponential declining relation with icing weight and a power functional declining relation with icing thickness and conductivity.Test results show that,the relation between two parameters of ice＇s extent is ： d=De-gW;therefore,the expression for DC flashover voltage of two types of insulators in the single or coexisting condition of contamination and icing is put forward,U_fmin=Eγ-m_20d-be-fW.