摘要
合理的绝缘子串布置方式是提高覆冰闪络电压的有效方法之一,但超高压覆冰绝缘子在不同配置下闪络特性缺乏基础试验研究。为此,以500kV交流绝缘子串为试品,对污秽绝缘子串进行带电覆冰后,在不同布置方式下对绝缘子串覆冰闪络特性进行了试验研究,分析了布置方式对绝缘子串的覆冰状况、闪络过程以及冰闪电压的影响。研究表明:双I型布置方式下放电发展过程中电弧经常由一边绝缘子串飘弧到另一边绝缘子串的串弧现象,短接了较多的沿面绝缘距离,因而其闪络电压低于单I串;V型串绝缘子伞间间隙不易桥接,绝缘子表面的污秽易于被融冰水冲刷而流失,提高了V型串的冰闪电压;"3+1"插花在轻中度覆冰条件下耐受电压高于500kV线路相电压,但在严重覆冰条件下冰闪电压低于500kV线路相电压。研究结论对不同冰区绝缘子串布置方式的选择有参考价值。
We experimentally researched 500 kV polluted and icing ac insulator strings under different arrangements,and analyzed the ice condition,flashover process,and flashover voltage of insulator string.The results show that,because of the arc floating from one side of the insulator strings to the other side in the discharge process,the distance along the surface of insulation is greatly shortened,resulting in the lower flashover voltage of double I string than that of I string in consequence.For the V string,the gaps between sheds are difficult to be bridged and the surface contamination can be easily washed away by molten ice,so the flashover voltage of V string is higher than the other two arrangements.If the insulator string is under light or moderate icing conditions,the flashover voltage of ＂3＋1＂ string is higher than the phase voltage of 500 kV AC power line;however,under severe icing conditions,the flashover voltage will be lower than phase voltage.The test results can be used to select arrangement method of insulator string for different icing regions.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2011年第12期3129-3134,共6页
High Voltage Engineering
基金
国家重点基础研究发展计划(973计划)(2009CB724503)
国家电网公司重大科技项目(SG0858)~~
关键词
覆冰
超高压交流输电线路
污秽
绝缘子串
闪络特性
布置方式
ice-covered
EHV AC transmission line
pollution
insulator string
flashover characteristics
arrangement
