高压开关柜内部电场仿真及其影响因素分析

Simulation of Internal Electric Field of High-voltage Metal-enclosed Switchgear and Influencing Factors

针对开关柜产品实际结构的复杂性,采用了分区建模、局部剖分细化等措施,建立了某型高压开关柜母线室三维电场有限元分析模型,获得了开关柜母线室中电场分布特征及电场集中区域。对母线室内电场最为集中的触头盒和穿墙套管等区域,进行了局部电场仿真,利用数值分析方法研究了绝缘隔板、均匀环和屏蔽罩等对局部电场分布的影响,得到了相应的优化措施。建立了开关柜母排搭接螺栓的有限元模型,通过量化分析,获得了不同间距下母排搭接的最大露牙数的参考值。上述分析结果,对于改善开关柜内部的电场分布、提高绝缘水平以及指导现场检修具有一定参考价值。

Considering the complexity of actual switchgear structures, a 3D finite element model of the electric field in a high-voltage metal-enclosed switchgear is built by using the sub-area modeling and partial subdividing methods. Hence, the distribution and concentration areas of the electric field in the bus cabinet of the switchgear are obtained. The most concentrative areas of electric field, such as the areas of wall bushing and contact box, are simulated. The numerical analysis technique is adopted to analyze the effects of insulating spacer, grading ring and shield on the local electric field distribution, and corresponding optimization is performed. In addition, a 3D finite element model of busbar overlapping bolt to obtain the reference value of maximum number of exposed bolt threads for different interval. This research may provide a reference for improving electric field distribution in switchgear, increasing insulation level, and guiding on-site maintenance.