电动汽车充电对配电网电压质量的影响研究

Study on the impact of electric vehicle charging on voltage quality of distribution network

大规模电动汽车接入居民小区配电网可能会引起电压质量问题,有必要建立有效的充电负荷模型,研究电动汽车充电对配电网电压质量的影响,为配电网的升级改造、充电桩的合理建设提供理论依据。文中提出了一种计及周末充电高峰效应的私家车充电负荷计算方法,该方法能够反映电动汽车用户的充电习惯,体现不同日期间充电负荷的差别。然后,利用MATLAB软件搭建了配电网模型,仿真分析了不同规模电动汽车接入配电网后对节点电压偏移、电压不平衡的影响,仿真设计了不同的场景,综合考虑了快速充电与慢速充电、纯电式与插入式电动汽车充电对配电网的不同影响,同时考虑了慢速充电在三相均衡充电与不均衡充电模式下对三相电压不平衡的影响。

Voltage quality may be influenced due to large-scale charging loads connecting to residential distribution network, it is necessary to establish an effective charging load model to study the impact of electric vehicle charging on the voltage quality of distribution network, which can provide the theoretical basis for the upgrading of distribution network and the reasonable construction of charging pile. Firstly, a calculation method of private car charging load considering the charging high peak effect at the weekend is proposed, and a more accurate charging load curve which can reflect the charging habits of users and the difference of charging loads can be obtained using this method. And then, the model of distribution network is established in MATLAB. The influences of different scales of electric vehicles assess to the network on the node voltage deviation and voltage unbalance and are simulated and analyzed, in the process of simulation, different scenes are designed. The different influenees of fast charging and slow charging, battery-electric and plug-in electric vehicle charging on the distribution network are considered. At the same time, the effects of slow charging in three-phase balanced charging and unbalanced charging mode on the three-phase voltage unbalance are considered as well.