污秽条件下避雷器的内部温升研究

Internal Temperature Rise of MOA Under Pollution Condition

金属氧化物避雷器(MOA)在污秽条件下的内部温升及其热稳定性是研究避雷器耐污能力的重要方面。为此,以GB 11032—2010附录O中的污秽试验方法为基础,同时参考IEEE Std C 62.11—1999,试验比较了不同盐密、不同支架高度等情况下进行人工污秽试验时避雷器的内部温升情况,同时还比较了复合外套及瓷外套避雷器的耐污能力及雾湿润条件对避雷器耐污能力的影响等。试验结果表明,仅监测底部阻性电流不能准确反映避雷器的内部热稳定性;考虑雾湿润进行污秽试验时内部温升较高且分散性小。最后提出了一个改进的污秽试验方法,主要增加了雾湿润条件和实时监测内部温度两个条件。

Using the test methods specified in the Annex O of GB 11032--2010 and IEEE Std C 62.11--1999, we compared the performances under pollution of polymer housed arrester and porcelain housed arrester, studied the impact of bracket height and fogs on the results, and analyzed the relation between the thermal stability of MOA and its leakage currents. The result shows that measurement o{ resistive component of current at the bottom of arrester is not enough to judge its thermal stability under pollution condition. Meanwhile, the internal temperature rise under pollution test with fogs is higher than that without fogs. At last, a possible artificial pollution test method of MOA is proposed based on the experiments and analysis.