基于有限元分析的252 kV绝缘子结构优化

Structure optimization of 252 kV insulator based on finite element analysis

GIS(GAS Insulated Switchgear)是气体绝缘全封闭组合电器,对于三相共箱的252 kV高压开关,三相绝缘子起着重要的支撑、绝缘作用。而三相绝缘子中的隔离绝缘子又起着隔离SF6与空气的作用,在检修过程中起重要作用。因此三相隔离绝缘子是252 kV GIS中非常重要的组成部分。隔离绝缘子由金属导体、嵌件、屏蔽件与环氧树脂在浇筑中成型。利用有限元分析方法进行电场及应力场的仿真计算,对隔离绝缘子、绝缘子三相导体的形状进行了优化,降低环氧树脂与金属导体结合面的应力。机械仿真的结果显示优化后结构与初始结构相比,结合面三交点应力下降了33.3%。通过水压实验中实验结果的数据表明,优化后的隔离绝缘子平均耐受水压载荷提高了34.9%,也验证了有限元分析的可靠性。优化后的三相隔离绝缘子,其电气性能不受影响。通过提高隔离绝缘子机械强度改善了高压开关设备检修方式,提高检修效率。

GIS(GAS Insulated Switchgear) is a gas-insulated fully enclosed combined electrical appliance. For 252 kV high-voltage switchgear, three phases are in common box, three-phase insulators play an important role in supporting and insulating. The three-phase barrier insulator also plays a role in isolating SF;from the air, and plays an important role during maintenance process. Therefore, the three-phase isolation insulator is a very important part of the 252 kV GIS. The isolation insulator is formed by metal conductors, inserts, shields and epoxy resin during casting. Using the finite element analysis method, the simulation calculation of the electric field and the stress field is carried out, and the shape of the isolation insulator and the three-phase conductor of the insulator was optimized to reduce the stress on the interface between the epoxy resin and the metal conductor. The mechanical simulation results show that the optimized structure has a 33.3% reduction in stress at the three intersections of the joint surface compared with the initial structure. The data of the experimental results in the water pressure experiment show that the optimized isolation insulator has an average water pressure load resistance increase of 34.9%, which also verifies the reliability of the finite element analysis. The electrical performance of the optimized three-phase isolation insulator is not affected. By improving the mechanical strength of the isolation insulator, the maintenance method of high-voltage switchgear is improved, and the maintenance efficiency is improved.