目前导线防覆冰技术已经相对成熟,而绝缘子的防覆冰方法仍处于实验室研究阶段,其中在绝缘子下表面涂覆半导体有机硅橡胶涂层的防覆冰方法已在人工气候室取得一定效果。为对半导体硅橡胶涂层电阻值的配置及相关的污闪问题进行研究,首先建立了基于热力学理论的绝缘子防冰热平衡模型,通过模型估算单片XP-70绝缘子涂层的电阻值,并在人工气候室内进行了防覆冰试验验证;重点讨论了电压、预染污方式对防冰效果的影响以及涂层对绝缘子污闪电压的影响。理论和试验结果表明:涂层电阻的范围在0.1~0-3MΩ以下时,涂层绝缘子具有较好的防冰效果,此结果可为中国输电线路及绝缘子防覆冰工作提供一定的指导。
The anti-icing and de-icing methods of insulator strings are still under laboratory studies, although many anti-icing technologies for overhead conductors have been relatively mature. The anti-icing method using semiconducting silicone rubber (SIR) coating applied to the bottom side of the insulators could get good results in a climate chamber. The configuration of the coating resistance and the subsequent pollution flashover problem were studied. A heating analytical method of insulators with semiconducting SIR was proposed. The resistance of the coating applied to the single XP-70 insulator was estimated. The anti-icing tests were carried out to verify the calculation results and the influence of the applied voltage and precontamination to the anti-icing performance was also discussed. The theoretical and experimental results show that the insulator would get a better anti-icing performance when the resistance is about 0.1-0.3MΩ, which can provide a guideline for anti-icing of transmission lines and insulators in China.