典型不溶污秽染污绝缘子在不同环境湿度下的吸水和闪络特性研究

Moisture Absorption and Flashover Properties of Insulators Polluted with Typical Non-soluble Contaminates in Various Environment Humidity

污秽绝缘子在表面湿润达到一定程度时容易发生放电甚至闪络,此现象严重威胁着输电线路的安全稳定运行。本文针对绝缘子表面常见的3种不溶污秽成分SiO2、Al2O3、Fe2O3,分别开展了不同环境湿度下的不溶物吸水试验和绝缘子闪络试验,并对试验结果进行了分析,探究环境湿度对不溶物吸水特性和绝缘子闪络特性的影响。结果表明:SiO2的吸水性最好,Al2O3次之,Fe2O3吸水性极弱或无吸水性;SiO2和Al2O3随着环境湿度的增加,吸水速度变快,且饱和吸水量增高;在饱和湿度下,SiO2和Al2O3染污绝缘子的表面污秽容易随着水滴的滴落而流失;绝缘子污闪电压梯度随环境湿度的增大而减小,此种现象在湿度较低的情况下表现得愈加明显。

Polluted insulators are easy to discharge or even flashover when the surface is wet to a certain extent,which seriously threatens the safety and stability of power grid.In this paper,in view of three kinds of common insoluble contaminates SiO2,Al2O3,Fe2O3,we conducted water absorption tests and insulator flashover tests under different environmental humidity,and the influence of environment humidity on the water absorption and flashover properties of insulators polluted with typical insoluble contaminates were analyzed.The results show that the SiO2has the best water absorption property,the Al2O3is followed,and the Fe2O3has extremely weak water absorption property or cannot absorb water absolutely.The moisture absorption rate and saturated moisture content of SiO2and Al2O3tend to increase with the increase of environment humidity.In the situation of saturated humidity,the surface contamination of insulators polluted by SiO2and Al2O3may be washed away with the dripping process ofliquid droplets.The pollution flashover voltage gradient of insulators decreases with the increase of environmental humidity,and this phenomenon is more obvious in low humidity.