基于Ansys仿真的开关柜局部放电研究

Research on Partial Discharge of Switchgear Based on Ansys Simulation

局部放电是预示电气设备绝缘状态的重要指标,电气设备内电场的分布与局部放电的产生密切相关。近年来,有关开关柜中母线室、电缆室、手车室、断路器处的电场分布得到了普遍关注并取得了重要研究成果,而针对开关柜内负荷开关本体电场分布的研究较少。文中运用静电场分析的方法,利用Ansys建模仿真得到开关柜内负荷开关处的电场分布图,找出电场强度相对集中的区域,确定了开关柜内负荷开关处易发生局部放电的位置,并通过实际运行状况进行了验证,这是开关柜局部放电监测的重要理论基础。笔者还考虑了环境湿度,通过改变周围环境相对介电常数,寻找到了负荷开关出线端表面电场强度的变化规律,在此基础上提出采取加装除湿器作为改善开关柜内部局部放电的措施。文中电场仿真结果还对同类型半绝缘开关柜负荷开关的结构设计及优化具有重要的指导意义。

Partial discharge（PD） is the important index of insulation conditions in electrical equipment,and the distribution of electric field in electrical equipment is closely related to the generation of partial discharge. In re- cent years, the research on the distribution of electric field in the bus room, cable room, handcart room, and circuit breaker inside a switchgear,have attracted widespread attention and already acquired important research results. However, there are few investigations on electric field distribution of load switch inside a switehgear. In this paper, the electric field distribution of load switch is obtained by using electrostatic field analysis with the software, Ansys, and some relatively concerned areas of the electric field have been observed. In addition, the position which is vulnerable to partial discharge in the interior of a load switch is verified by the actual operating status of equipment, and those research conclusions are the basis of theory of the partial discharge monitoring. Considering the humidity of the ambient environment ,this paper changes the relative dielectric constant of environment, and the relevant change rules of electric field intensity in the surface of outgoing line ends are found out,based on which,installing a dehumidifier inside a switchgear as an effective measure for suppressing partial discharge is proposed. What＇s more, the whole electric field simulation results have important guidance significance for the structure design and optimization of load switch inside the same type semi-insulatinz switchzear.