喀斯特山地垭口地貌影响下直流线路复合绝缘子伞裙老化特性分析

Analysis on Aging Characteristics of the Sheds of DC Composite Insulator under the Influence of Karst Mountain Col Geomorphology

为研究运行于喀斯特山地垭口地区直流线路复合绝缘子伞裙老化特性的特殊性,从喀斯特山地垭口及平原地区分别选取相同运行年限的绝缘子,进行伞裙憎水性、积污量和污秽成分的测试,对比分析了二者伞裙性能表现出的差异,并讨论了引起此种差异的可能影响因素。结果表明,运行于喀斯特山地垭口处的直流复合绝缘子伞裙整体老化程度偏重,这是受该地区特殊地形、气象和污秽成分等因素的共同影响造成的。垭口的强风经过伞裙会产生应力集中,使得伞裙根部出现裂纹;若酸性液体从表面及裂纹渗入,则会加速内部硅橡胶的裂解和老化;同时伞裙表面富集的碳酸盐在酸性环境下会逐渐转化为更有腐蚀性的硫酸根离子,引起伞裙表面粉化及腐蚀等现象。

In order to study the particularity of the aging characteristics of DC composite insulator sheds operating in the karst mountain col area,insulators with the same operating life from the karst mountain col and plain areas are selected.Shed hydrophobicity,contamination quantity and composition are tested,then performance differences between the two are compared,and the possible influencing factors that cause such differences are discussed.The results show that the overall aging degree of the DC composite insulator sheds operating at the karst mountain col area is rather serious,which is caused by the combined influence of factors including the special terrain,weather,and pollution in the area.The strong wind passing through the sheds will cause stress concentration,leading to cracks at the root of the shed;the penetration from the surface and cracks of acid liquid,if any,will accelerate the cracking and aging of the internal silicone rubber;moreover,the carbonates enriched on the shed surface will gradually transform into more corrosive sulfate ions in an acidic environment,leading to pulverization and deeper corrosion of the shed surface.