车顶绝缘子空气动力结构优化及其电气性能

Aerodynamic Structure Optimization and Electrical Performance of Roof Insulator

高速列车运行时车顶高压绝缘设备暴露于高速气流环境之下,此时外绝缘特性与无气流工况下相比具有明显的差异。该文根据车顶绝缘子在气流环境中的闪络特性与放电路径偏移现象提出了2种车顶绝缘子空气动力型结构优化方案,并利用3D打印技术制作车顶绝缘子试验模型。同时采用有限元仿真软件对空气动力型车顶绝缘子的周围气流状况与电场分布特性进行分析,并通过风洞试验系统开展气流环境下的闪络特性试验。结果表明:相比于传统结构绝缘子,2种空气动力型结构表面场强的最大值与平均值更小,在风速100 m/s时闪络电压分别提高了11.3%与8.5%,气流的存在影响了电子、离子与亚稳态粒子在电场中的运动方式,从而影响了放电形成过程。优化后的车顶绝缘子表现出更优良的空气动力学特性,在气流环境中其外绝缘性能相比于传统结构有所提高。

The high voltage insulation equipment on the roof of high-speed train is exposed to the high-speed airflow environment while the high-speed train is running.Thus its external insulation characteristics are significantly different from those without airflow.In this paper,according to the flashover characteristics and discharge path deviation phenomenon of roof insulators in airflow environment,two kinds of aerodynamic structure optimization schemes of roof insulators were proposed,and the test models of roof insulators were fabricated by 3 D printing technology.Finally,the finite element analysis software was used to analyze the surrounding airflow conditions and the electric field distribution of the aerodynamic roof insulator,and the tests for flashover characteristics under the airflow environment were carried out through the wind tunnel test system.The results show that the maximum and average values of the surface field strength of the two aerodynamic insulators are lower compared to those of traditional structural insulator;under the condition of wind speed of 100 m/s,their flashover voltages increase by 11.3% and 8.5%,respectively,and the existence of airflow affects the motion mode of electrons,ions and metastable particles in the electric field,affecting the discharge formation process.The optimized roof insulator exhibits better aerodynamic characteristics,and its external insulation performance in the airflow environment is improved compared to the traditional structure.