电动汽车接入充放电对配电网继电保护的影响

Influence of Electric Vehicle Charging and Discharging on Distribution Network Relay Protection

随着电动汽车的逐渐普及,具有可移动储能性质的电动汽车将大量接入配电网进行充放电。这影响了配电网原有的电源、负荷以及网络结构,改变了配电网的潮流水平及方向,势必给配电网的继电保护造成了极大的影响。除此之外汽车在时间与空间上还具有很强的充放电随机性,这会给配电网的继电保护配置及整定造成困难。对此,文中基于电动汽车放电时的分布式电源特性与充电时的随机负荷特性,对电动汽车接入配电网充放电时的故障特征进行梳理与总结,分析了电动汽车对配电网中电流保护、距离保护及重合闸受到的具体影响。最后,并以此为基础,探讨了大量电动汽车渗透下配电网的继电保护研究方向,为配电网保护的后续研究提供参考。

With the gradual popularization of electric vehicles, numerous electric vehicles with removable storage property will be connected to the distribution network for charging and discharging. This affects the original power supply, load and network structure, changes the power flow and direction of distribution network, which will cause a great impact on the relay protection of distribution network. In addition to, charging and discharging behavior is ran- dom in time and space, which will make difficulties for configuration and setting calculation of relay protection. Based on the characteristics of distributed generations of discharging process and characteristics of random loads of charging process, this paper introduces a summary to the faults characteristics of electric vehicles charging and dis- charging in distribution network. The effects of electric vehicles on the current protection, distance protection and re- close of distribution systems are analyzed. Finally, on the basis of this, the research direction of the relay protection under the infiltration of electric vehicles is discussed, which provides reference for the future research of the distribu- tion network protection.