雷电发展对高速铁路周围电场分布影响的研究

Effect of Lightning Development on Electric Field Distribution Around High-speed Railway

雷害是影响高速铁路安全稳定运行的关键因素之一,研究雷电先导作用下高速铁路周围电场的变化规律对于高速铁路雷击机理的阐明具有重要意义。文中结合先导法建立了高速铁路三维雷击仿真模型;通过调整导体携带电荷量、高度及侧面距离,来模拟不同雷电流幅值以及先导空间位置对高速铁路周围电场分布的影响;并对比分析了高架区段和路基区段高速铁路周围场强分布情况。研究发现,在雷电流幅值为数千安时,高速铁路周围仍有上行先导产生,因此认为在雷击计算中,雷电流较小情况仍需考虑上行先导;随着雷电流幅值、下行先导空间位置的变化,避雷线总是比其他导线更容易产生上行先导;高架区段接触网场强值约为路基区段的1.4倍,因此高速铁路雷电防护的防雷设计施工要求高架区段应高于路基区段。

To understand the change of electric field strength around high-speed railway under the effect of lightning downward leader and further reveal the lightning mechanism of high-speed railway,leader progression model is adapted to build a three-dimensional lightning strike model.By adjusting the charge, height and lateral distance of the conductor,the effects of lightning current amplitude and progression of downward leader nearby the earth on the electric field strength distribution around high-speed railway are simulated,and the electric field strength distribution in viaduct section is compared with that in rail-bed section.Results show that upward leader still occurs around high-speed railway while the amplitude of lightning upward leader should be considered even under little lightning lightning wire generates upward leader easier than the other current is several kiloamperes.It is proposed that current in lightning calculation.Research finds that conductors while adjusting the space location of downward leader and changing amplitude of lightning current.And it finds that electric field strength of viaduct section is 40% higher than that of roadbed section, so lightning protection designation and construction requirement of high-speed railway in viaduct section should be higher than that in roadbed section.