基于有限元的 35 kV 气体绝缘母线放电机理及改进方案研究

Ｒesearch on the Mechanism of Partial Discharge in 35 kV GIL and Improvement Scheme Based on Finite Element Modeling

摘要:

随着城市供电集约化的不断推进，气体绝缘金属封闭输电线路( GIL) 在城市变电站中的应用愈加广泛。而在 特大型城市上海，有着大容量、集成化以及环境友好性等特点的 GIL 已经逐渐替代了敞开型母线，被大规模地应用于 城区变电站中。但在运行过程中发生过多起 GIL 内支撑绝缘子局部放电故障。结合 35 kV 气体绝缘母线的专项技术 改进工作，建立有限元模型对 GIL 支撑绝缘子局部放电产生机理进行仿真计算，提出一种改进技术方案并进行理论 验证。仿真及实际运行结果显示，改进方案能够较好地解决支撑绝缘子放电故障，提高了运行的可靠性。

Abstract:

As the power supply intensity keeps growing in large cities，the gas － insulated metal － enclosed transmission line ( GIL) has been widely used in urban substations． Especially in the ultra － large cities such as Shanghai，GIL has gradually substituted the traditional open － type bus benefited from its large capacity and smaller space demand． However，several partial discharge faults have occurred on the support insulator during the operation． A finite element model is established and the mechanism of partial discharge is simulated． With the calculation result，an effective improvement scheme is proposed． The model simulation and practical implementation show that the improvement scheme can eliminate the partial discharge on support insulator，which can greatly improve the operation reliability of GIL．