环氧树脂沿面缺陷放电仿真中的临近击穿判据  

The near-breakdown criterion of epoxy resin surface defectsin the discharge simulation

作　　者：张钊棋 宋辉[1] 罗林根[1] 钱庆林 盛戈皞[1] 江秀臣[1] ZHANG Zhaoqi;SONG Hui;LUO Lingen;QIAN Qinglin;SHENG Gehao;JIANG Xiuchen(Department of Electrical Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]上海交通大学电气工程系,上海200240

出　　处：《电机与控制学报》2025年第2期14-23,共10页Electric Machines and Control

基　　金：国家自然科学基金(52007117);国网上海市电力公司科技项目(520950220004)。

摘　　要：为了探究在仿真中判断沿面缺陷临近击穿的方法,从而为基于仿真系统的设备绝缘状态感知提供理论支撑,首先开展高压试验,测量不同长度间隙的沿面击穿电压;进而构建等离子体仿真模型,仿真相同尺寸缺陷的放电过程,分析不同长度缺陷的放电微观情况。研究发现,仿真中电压主要影响沿面流注发展末期的电流上升阶段与电流衰减阶段;在电流衰减阶段,击穿电压下间隙阳极附近电导率会在上升至极大值后缓慢下降,且在不同长度间隙中的数值变化规律一致,可作为击穿前放电通道临近击穿的表征物理量;对比不同长度间隙仿真结果发现,若电流衰减阶段阳极附近放电通道电导率的最小值可以上升到0.9 S/m以上,即可认为仿真中的缺陷达到临近击穿状态。经验证提出的判据能够对仿真中不同长度沿面缺陷临近击穿状态作出判断。To explore the method of determining the near-breakdown status of surface defects in simulations,and further provide theoretical support for the perception of insulation status based on the simulation system,first a high-voltage test was carried out to measure the surface breakdown voltage of different length gaps.Then a plasma simulation model was constructed to simulate the discharges of the same insulation defect,and the micro-processes of different length defects were analyzed.The study shows that voltage mainly affects the current rising and decay stage at the end of the surface streamer.In the decay stage,the conductivity near the anode decreases slowly after rising to a maximum value under the breakdown voltage.The conductivity of this section has almost the same numerical change pattern in gaps of different lengths,which can be regarded as a physical quantity characterizing the critical state of the discharge channel before breakdown.By comparing the simulation results of gaps of different lengths,it can be concluded that if the minimum conductivity of the discharge channel near the anode during the current decay stage can increase to above 0.9 S/m,it can be considered that the defects in the simulation turn near-breakdown in actual discharge.It was verified that the numerical criterion could judge the near-breakdown state of surface defects of different lengths in the simulation.

关 键 词：沿面缺陷 放电仿真 环氧树脂 临近击穿 电导率 等离子体模型 

分 类 号：TM854[电气工程—高电压与绝缘技术]