高电导率雾对复合绝缘子憎水性的影响

Influence of High Conductivity Fog on the Hydrophobicity of Composite Insulator

沿海地区的海雾以及城市工业区的浓雾,其雾水的电导率高,会导致绝缘子快速积污,并可能对复合绝缘子憎水性能产生影响,研究了高电导率雾环境下染污硅橡胶表面的憎水性能变化过程。利用超声波雾发生装置来产生高电导率雾,在小雾室内使染污的硅橡胶试片受潮,采用静态接触角法测量染污试片表面的憎水性在受潮前后的变化。试验发现,在高电导率雾中受潮会导致染污硅橡胶试片表面的憎水性下降。受潮结束后,污层表面的憎水性恢复情况和污秽物中的不溶物成分有关;污秽中可溶盐成分与不溶物成分的比值越高,对憎水性恢复越不利;此外,环境湿度越高,越不利于憎水性恢复。分析认为,高电导率雾导致硅橡胶表面污层的盐密值增加,增强了污层的吸水能力,是染污硅橡胶表面憎水性下降的原因。

The fog water in the coastal area and in urban industrial area usually has high conductivity. It will cause rapid contamination accumulation on the composite insulators in service and affect their hydrophobicity state. This paper discusses about the change of hydrophobicity of the polluted silicone rubber surface in high conductivity fog environment. Ultrasonic fog generator was used to generate high conductivity fog and polluted silicone rubber was affected with damp in the mini fog chamber. The hydrophobicity status of the pollution surface was measured with the static contact angle method before and after staying in the damp. The results show that the hydrophobicity of polluted surface decreases after staying in the damp of high conductivity fog. The non-soluble deposit plays a role in the recovery of hydrophobicity of the pollution layer after affected with damp. It is more unfavorable for the recovery process with the higher ratio of salt deposit density to non-soluble deposit density, as well as the higher ambient humidity. Analysis shows that wetting in the damp of high conductivity fog will increase the salt deposit density of the pollution surface and enhance its ability of moisture absorption, causing the decrease of hydrophobicity of the polluted surface.