导线表面缺陷下的电场强度仿真及测试

输电线路在生产、安装和运行等过程中由于人为或自然环境可能会形成表面缺陷，引发局部场强畸变，可能导致电晕乃至放电，从而威胁线路的正常运行。本文利用COMSOL建立导线的三维模型，计算导线表面完好和存在毛刺、单线拱起和单线断股时导线周围的电场分布图和曲线，比较得出导线表面存在不同缺陷时周围的电场变化特性。在实验大厅搭建了测试平台，根据仿真设置的条件进行了试验验证，利用光学电场传感器分别测量了导线完好和存在毛刺、单线拱起和单线断股时电场的变化趋势。仿真和测试结果表明，导线表面存在不同类型的缺陷时，缺陷周围空间电场强度会有不同程度的上升，且随测量距离的增加，不同类型的缺陷衰减速度也不同，因此可以通过对比分析这个规律对表面缺陷类型进行区分。

Electric Field Simulation and Testing on Surface Defect of the Wire

In the process of production, installation and operation of transmission lines, surface defects may be formed due to man-made or natural environment, resulting in local field strength distortion, which may lead to corona and even discharge, thus threatening the normal operation of transmission lines. A three-dimensional model of the wire was established based on the COMSOL and the electric field distribution around the wire is calculated when the surface is intact and there are burr, single line arch and single strand break. The differences and similarities were compared to obtain the characteristics of electric field around the wire surface with different defects. The test platform was set up in the laboratory, and the test was carried out according to the conditions of the simulation. Optical electric field sensors were used to measure the variation trend of electric field when wires were intact and burred, single arched and single broken. The simulation and test results show that when there are different types of defects on the surface of the wire, the strength of the electric field around the defect will rise in varying degrees, and with the increase of the measuring distance, the attenuation speed of different types of defects is also different, so the type of surface defect can be distinguished by comparison and analysis.