中文摘要：

以硅橡胶为主的复合绝缘材料广泛应用于高电压外绝缘领域，因其憎水性和憎水迁移性能有效提高线路绝缘子污闪电压。但是，运行多年后硅橡胶材料会发生局部老化，表面憎水性不均匀下降，这种情况下线路绝缘子的防污效果有着重要的研究意义。针对复合绝缘子沿串憎水性以及RTV涂料绝缘子上、下表面憎水性的不均匀分布特点，应用人工污闪试验和饱和受潮试验表现其防污性能。试验结果表明：复合绝缘子高压端憎水性下降对绝缘子整体防污性能影响较大；而悬垂绝缘子上下表面的饱和受潮时间和污秽流失情况决定了整体受潮状态，其中下表面的憎水性状态对其防污效果至关重要。根据上述试验结果，在运行状态评价中，复合绝缘子高压端以及悬垂绝缘子下表面的憎水性应给予重点关注。

英文摘要：

Composite insulating material, silicone rubber primarily, is widely used in the field of high voltage outdoor insulation. The higher pollution flashover voltage of line insulators benefits from the hydrophobicity and hydrophobicity transfer of silicone rubber. However, silicone rubber served over many years shows partial degradation which leads to uneven hydrophobicity on surfaces of insulators. It’s of great research significance for effect of uneven hydrophobicity on anti-pollution flashover performance of line insulators. Base on the uneven distribution characteristics of hydrophobicity along composite insulators and hydrophobicity on upper or lower surfaces of RTV coated insulators, anti-pollution flashover performance is measured with artificial pollution flashover test and saturated wetting test. Experimental results indicate that the hydrophobicity of high-voltage end has a great impact on anti-pollution flashover performance. In addition, for pendent insulators, the integral wetting state is depended on the saturated wetting time of both surfaces and the situation of contamination loss. Therefore, the hydrophobicity of lower surface is crucial for anti-pollution flashover performance. According to the above test results, the hydrophobicity of high-voltage end for composite insulators and lower surface for pendent insulators should be paid more attention in operation state assessment.