GIS设备有限元结构分析研究

Finite Element Structural Analysis of GIS Equipment

以某500 kV变电站GIS(气体绝缘金属封闭开关)设备为研究对象建立有长限元结构模型,仿真计算了不同温度下整体GIS管道母线的应力与应变,与实际监测数据进行对比验证其可靠性,为GIS设备的结构优化和监测预警提供理论依据。同时研究了轴向伸缩位移自平衡式波纹管膨胀节支反力的变化规律。分析结果表明:在不同温度下,最大轴向应变位于自平衡式波纹管两侧,最大应力点位于最外端自平衡式波纹管;在极限工况下GIS设备中母线筒与波纹管膨胀节的连接处出现应力集中,存在屈服和开裂风险;有限元仿真计算与实际监测结果一致,自平衡波纹管膨胀节连接螺栓预留间隙对于波纹管弹性支反力影响很大,母线实际位移大于预留间隙时支反力急剧增大。

By investigation on GIS equipment of a 500 kV substation,a finite element structural model was established.The stress and strain of the integral pipeline GIS busbar at different temperatures were simulated and calculated.At the same time,the reliability of simulation analysis was verified by comparison with the actual monitoring data,providing the theoretical basis for GIS equipment structure optimization,monitoring and early warning.Besides,the changing rule of the expansion joint reaction force of self-balanced bellows with axial expansion displacement is studied.The analysis result shows that at different temperatures the maximum axial strain is located on both sides of self-balanced bellows,and the maximum stress point is located at the outermost end of self-balanced bellows;under extreme working conditions,stress concentration occurs at the joint of busbar barrel and bellows expansion joint in GIS equipment,which may lead to yield and cracking risk;the results of finite element simulation are consistent with the actual monitoring data,and the reserved clearance of self-balancing bellows expansion joint connection bolt has a great influence on the elastic reaction force of bellows;when the actual displacement of the busbar is larger than the reserved clearance,the reaction force increases sharply.