复合绝缘予由于伞群间距较小,与玻璃和瓷质绝缘子相比更容易发生覆冰闪络。为了研究复合绝缘子的冰凌生长特性,针对短串复合绝缘子进行了电场仿真分析和覆冰试验,得到了冰凌生长与电场分布之间的作用关系,并研究了电压和环境因素对复合绝缘子冰凌生长过程的影响。结果表明,冰凌生长与电场分布相互作用,当尖端最高场强达到30kV/cm时,局部电弧使冰凌生长速度减缓甚至停止;试验过程中沿串泄漏电流大小和局部放电程度受电压、环境温度、覆冰水电导率、降雨强度和染污程度等因素的影响,进而影响冰凌的生长过程和桥接情况,增大施加电压、环境温度、覆冰水电导率、染污程度或减小降雨强度均能延缓绝缘子冰凌生长速度。
Composite insulators have relatively small shed spacing, so they are more likely to have icing flashovers than their glass and porcelain counterparts. To study the icicle growth on composite insulators, electric field simulations and icing tests of short insulator strings were performed, from which we obtained the relationship between the icicle growth and the electric field distribution. The influence of voltage and environment factors on the icicle growth was also re- searched. The results show that, the icicle growth interacts with the electric field distribution, and local arcs can slow down or even stop the growth of icicles when the maximum electric field intensity reaches about 30 kV/cm. All the fac- tors, such as the voltage, environment temperature, water conductivity, rainfall intensity, and pollution degree, which influence the leakage current value and local discharge density, influence the growth and bridging of icicles. The increas- ing of the applied voltage, environment temperature, water conductivity, and pollution degree, as well as the decreasing of the rainfall intensity, can slow down the growth of icicles.