动车组车顶隔离开关用支柱绝缘子污秽状态下的电场分布特性研究

摘 要：研究污秽状态下支柱绝缘子的电场分布特性对于动车组的安全稳定运行具有重要的意义。本文以FQJG2-30-16-400-M型车顶复合支柱绝缘子为研究对象，进行如下研究：对绝缘子表面进行淋雨试验，同时施加40kV工频电压，靠近金具部分的伞裙首先发生闪络，且出现了干燥带，伞裙边缘形成大粒径的水珠时，容易引发局部放电。利用comsol有限元分析软件在绝缘子靠近金具的伞裙表面设置干燥带和水珠，护套表面存在干燥带时，电场畸变明显，杆径处的干燥带场强最大，上表面干燥带场强大于下表面干燥带场强，干燥带场强最大值随着干燥带数量增加反而减小。绝缘子表面出现水珠时，水珠附近的场强明显增大，越靠近中轴线水珠表面电场强度越大。靠近高压端的水珠的最大电场强度受半径的影响较大，低压端则不明显。

Research on the Flashover Characteristics under polluted condition of EMU High Voltage Isolation Switch Insulators

Abstract: It is of great significance to study the electric field distribution characteristics of post insulators under pollution conditions for the safe and stable operation of EMU .In this paper, the FQJG2-30-16-400-M model roof composite pillar insulator is taken as the research object, and the following research is carried out: the surface of the insulator is subjected to rain test, and 40kV voltage is applied. Flashover occurs first in the skirt close to the gold fittings, and the dry band appears. When the skirt edge forms large particle size of water droplets, partial discharge is likely to occur. Using finite element analysis software comsol in insulator with the near umbrella skirt set dry band and water surface, the surface of the sheath dry band exists, the electric field distortion, stem diameter in the dry band field intensity, the largest on the surface with dry field strength is greater than the surface dry field, dry with a maximum field strength as dry with increase in the number decreases. When water beads appear on the surface of an insulator, the field intensity near the beads increases significantly, and the closer to the central axis the beads are, the greater the electric field intensity is. The maximum electric field intensity of water droplets near the high pressure end is greatly affected by the radius, while that near the low pressure end is not obvious.