输配电线路复合绝缘子的选择与防污闪措施

分析了输配电线路绝缘子污闪的危害,指出,选择伞裙上表面为小倾角、下表面为平板无滴水沿结构的复合绝缘子,可以明显减少污秽物堆积、防止伞裙结构变形;最好选择水平串绝缘子,其上下均能被雨水冲刷,而且自洁性好。提出了检修时防污闪的方法:增加串联盘形悬式绝缘子的片数(35kV线路用4～5片,110kV线路用8～10片);采用耐污秽型且伞形扩张较大的盘形悬式绝缘子;增加棒形绝缘子伞数或采用特殊伞形。使用高温硅橡胶密封可明显减少芯棒脆断的发生,同时增加绝缘子串长以抵抗雷击。

Selection of Composite Insulators for Transmission Lines and Anti-pollution Measures

The pollution flashover hazard of insulators for overhead lines was analyzed.It is present that selected composite insulator with slight leant upper shed surface and plain underneath surface without water dropping ribs could apparently decrease pollution deposit and prevent from shed deformation.Horizontal insulator string is preferred for it can be washed by rain at both surfaces having good self-cleaning performance.To prevent pollution flashover,it is recommended to increase string insulator number(4～5 units for 35 kV and 8～10 units for 110 kV),select anti-pollution with increased cap and pin type insulators with large shed overhang,select rod insulator with increased shed number or with special shed profile.Fitting end sealing with HTV may apparent decrease probability of brittle fracture occurrence,and increase of insulator string length may improve the lightning strike resistance.