XP-7瓷绝缘子耐张串的表面电导率与污闪电压相关性

Correlation between Surface Conductivity and Pollution Flashover Voltage of XP-7 Strain Insulator-String

针对6～10kv中压瓷绝缘子XP-7耐张串的污闪事故．分析了近年来重庆局部地区电网污闪事故与绝缘子表面污秽度的关系．通过对瓷绝缘子表面污层电导率指标和污闪电压的计算分析。来推广不同电压等级下污秽绝缘子的事前更换预警可行性。试验结果表明。局部电导率指标和污闪电压有着密切的相关性．用作基准的电导率指标的实测电压和估算电压应控制在±10％以内。后期推广阶段应再细化电导率指标和污闪电压一一对应的关系．确保数据的真实等价性．为在线预警监测系统地研制提供有力支撑。

For contamination of the 6-10 kV medium voltage insulators XP-7 strain insulator-string, the analysis is made to the localized pollution flashover accident in Chongqing in recent years with a surface of insulator contamination degree of relationship. Through the surface of porcelain insulator pollution layer conductivity indicators and calculation analysis on pollution flashover voltage, the feasibility of early warning for replacing the contaminated insulator with different voltages is promoted. Results show that, the relationship between pollution flashover voltage and conductivity parameters is clear; the measured and estimated voltages which are used to the reference of the conductivity should be controlled in ±10%. The corresponding relationship in future application of the conductivity and the pollution flashover voltage should be more quantitative in order to guarantee the data equivalence and the development the early warning and monitoring system.