复合绝缘子表面憎水性和污秽对其湿闪电压的影响

提出一种染污复合绝缘子的湿闪络试验方法，给出不同憎水性和污秽条件下复合绝缘子的干、湿闪电压，并根据试验结果对其干、湿闪机理进行了分析。试验结果表明：复合绝缘子的湿闪电压随表面憎水性的减弱而降低，干闪电压与表面憎水性无关；表面存在污秽时，绝缘子的湿闪电压较清洁表面有明显下降；其表面憎水性的不同仍然影响着复合绝缘子的湿闪电压；在不同盐密条件下，涂污的复合绝缘子湿闪电压也随表面憎水性的减弱而降低；重污秽条件下其表面憎水性较差时的湿闪电压要比憎水性良好时下降11％。

The wet-flashover performance of composite insulators in different hydrophobicity and pollution class

A wet-flashover test method of polluted composite insulators was presented. The dry-flashover and wet-flashover voltage of composite insulators was put forward. Based on test result, the flashover mechanism was studied. The wet-flashover voltage of composite insulators descends with surface hydrophobicity decreasing, while the dry-flashover voltage is independent of surface hydrophobicity. The polluted insulators have obviously lower wet-flashover voltage than the clean ones. The wet-flashover voltage of polluted composite insulators also relates to surface hydrophobicity. Under severe pollution condition, the wet-flashover voltage of composite insulators with well surface hydrophobicity has a 11 % decrease than that of bad hydrophobicity ones.