中文摘要：

在覆冰、大雾以及污秽在冰面沉降的条件下,绝缘子的绝缘性能下降,轻覆冰条件下输电线路的复合绝缘子曾发生闪络事故。为了解轻覆冰时憎水性对复合绝缘子闪络电压的影响,在人工覆冰气候室中开展了全尺寸复合绝缘子覆冰闪络试验,试验中采用升压闪络方法。通过试验发现,当复合绝缘子具有良好憎水性时,其冰闪电压较高;当绝缘子的憎水性消失时,其冰闪电压比同等盐密下的污闪电压更低。复合绝缘子的憎水性在防止轻覆冰条件下的发生的闪络事故,起着重要的作用。轻覆冰条件下的覆冰绝缘子的闪络,可以看做是一种复杂的污闪,电弧的发展基本都是沿着绝缘子的伞裙表面发展,因此增加爬距而不增加结构高度的方式是一种有效的防闪络事故的措施。

英文摘要：

The icing flashover accident occurs on the composite insulator strings under light ice accumulation conditions.The performance of insulators deteriorates under light ice accumulation and wet contamination deposition conditions.In order to deeply investigate the impact of hydrophobicity on ice flashover performance,experiments of full-size composite insulators were carried out in artificial climate chamber using rise-voltage method.In our tests,the icing flashover voltage of composite insulator with good hydrophobicity was quite high,while icing flashover voltage of the composite insulator without hydrophobicity was lower than the contamination flashover voltage when they were both pre-contaminated with the same equivalent salt deposit density（ESDD）.Hydrophobicity of composite insulators plays an important role in preventing the occurrence of flashover accident under light ice accumulation and wet contamination deposition conditions.Flashover under light icing conditions can be considered as one kind of pollution flashover and partial arcs are always developed along the surface of shed,thus increase creepage distance while keep the structure height constant is an effective way to prevent flashover in light icing condition.