新能源汽车充电站浪涌侵入波防护分析

Lightning Surge Protection forthe New Energy Vehicle Charging Station

新能源汽车的广泛推广带动了汽车充电站的逐步建设,但是充电站也面临着严重的雷电灾害威胁。为了实现对充电站的有效防护,首先利用ATP-EMTP软件建立充电站简化模型,计算充电站不同部位雷电浪涌过电压,分析充电桩安装末端电涌保护器的防护效果;然后,讨论雷击点距变压器高压侧距离、配电柜与充电桩连接电缆长度、末端电涌保护器接地电阻对终端浪涌过电压的影响。研究结果表明:高压侧线路遭受雷击后,传递至配电柜和充电桩的雷电过电压波形呈现较为明显的尾部振荡,电压幅值较高;在充电桩末端安装电涌保护器后能够进一步抑制充电桩末端浪涌过电压,雷击点距变压器高压侧距离越远,过电压幅值越高;配电柜与充电桩连接电缆长度影响充电桩末端过电压,电缆长度越长,过电压幅值越高。接地电阻对充电桩末端电涌保护器的防护效果影响很大,接地电阻阻值越高,电涌保护器保护效果越差,需尽可能降低接地电阻。

The popularization of electric vehicles drives the rise of charging stations, which has brought a serious lightning disaster threat. In order to protect charging stations properly, lightning surge protection should be investigated. Firstly, a simplified model was established in ATP-EMTP to calculate lightning surge overvoltage at different position of the charging station and the protection effect of terminal surge protect device(SPD) was analyzed. Effects of distance from lightning strike point to the transformer, length of the connecting cable, ground resistance were discussed. Research results show that: surge overvoltage of the low-voltage distributor and the charging pile show obvious oscillation in the tail and amplitudes remain high. Overvoltage of the charging pile can be further reduced when terminal SPD is installed. Surge overvoltage of the charging pile increases with the increasing of distance from lightning strike point to the transformer as well as length of the connecting cable. The ground resistance has a great influence on protection effect of terminal SPD, the higher the grounding resistance, the worse the protection effect of surge protector, it is essential to reduce ground resistance as low as possible.