500kV输电线路绝缘子融冰闪络事故分析及应对措施研究  

Analysis and Countermeasures of Ice-melting Flashover for Ice-covered Insulator Strings of 500 kV Transmission Line

作　　者：巢亚锋[1] 黄福勇[1] 蒋兴良[2] 周卫华[1] 王成[1] 

机构地区：[1]湖南省电力公司科学研究院,长沙410007 [2]重庆大学输配电装备及系统安全与新技术国家重点实验室,重庆400044

出　　处：《高压电器》2013年第7期60-65,70,共7页High Voltage Apparatus

摘　　要：绝缘子融冰闪络已成为影响输电线路安全运行的一个重要问题,目前国内外关于双联绝缘子融冰闪络事故的分析还鲜见报道。笔者基于两次500 kV线路双联绝缘子融冰闪络障碍,分析了长绝缘子串融冰闪络的影响因素,研究了覆冰水由液态至固态相变过程中"晶释效应"对覆冰水中电解质和杂质重新分布的影响,分析了并联和间插布置及串长对绝缘子串融冰闪络电压梯度的影响,确定了交流500 kV输电线路融冰闪络电压梯度以65 kV/m为基数,针对I型和II型悬垂串,提出了采用改变布置方式和改造塔头等综合措施来防止长绝缘子串融冰闪络的建议。Although ice-melting flashover of insulator strings has become one of the important problems which have a severe impact on the safe operation of transmission lines,the analysis of ice-melting flashover for ice-covered parallel insulator strings is rarely to see.This paper study on the impact factors of ice-melting flashover based on two times of ice-melting flashover obstacles in field for ice-covered long insulator string of 500 kV transmission line.The influence of crystallization effect on the redistribution of conductive ions during the freezing water transition from liquid to solid phase is discussed.The impact of parallel arrangement,units and structured with alternately large and small diameter sheds on the ice-melting flashover gradient of insulator strings is analyzed.The base value of AC ice-melting flashover voltage gradient of 500 kV transmission line is determined as 65 kV/m.To type I and type II suspension insulator strings of 500 kV transmission line,the countermeasures such as change the arrangement mode of insulators and reform the tower head to prevent ice-melting flashover are proposed.

关 键 词：输电线路 覆冰 融冰水 晶释效应 闪络 应对措施 

分 类 号：TM216[一般工业技术—材料科学与工程] TM85[电气工程—电工理论与新技术]