磁浮列车接地系统雷电冲击响应分析与优化

Analysis and Optimization of Lightning Impulse Response of Maglev Train Grounding System

为研究磁浮列车接地系统应对雷电冲击时的响应,笔者建立了接地系统的集总参数电路模型,分析了雷电流峰值和雷击位置对车体接地系统的泄流分布特性和电压峰值特性的影响,并基于研究结果提出一种有效抑制雷电冲击影响的优化措施。研究发现:雷电流通过击穿车体导向电磁铁和轨道之间的间隙从而泄入大地,在这个过程中,被击穿的间隙呈现分布不均且不可控的特点,遭受直击雷的车体具有更多的泄流通道和更高的电压峰值;距离雷击点较远的某些车厢则没有出现泄流通道,这使得尾部车厢的接地系统电压峰值有一定程度抬升。通过一种开关式的引雷结构能够有效控制雷电流的泄流路径,并抑制接地系统的电压峰值。

In order to analyze the response of the maglev train grounding system to lightning impulse, the lumped parameter circuit model of the grounding system is established. The influence of lightning current peak value and lightning stroke position on the characteristics of current discharge distribution and voltage peak value of the grounding system is analyzed. Based on the research results, an effective optimization measure to suppress the impact of lightning impulse is proposed. It is found that the lightning current breaks through the gap between the guide electromagnet and the track and then leaks into the earth. In this process, the breakdown gaps are uneven and uncontrollable. The body suffering from direct lightning has more discharge channels and higher voltage peak value. Some carriages far away from the lightning strike point have no discharge channel, which makes the voltage peak of the grounding system of rear carriages rise to a certain extent. An induced structure of switch type can effectively control the discharge channel and suppress the voltage peak of the grounding system.