电动汽车对配电网的无功补偿方法  

Reactive Power Compensation Method for Distribution Network from Electric Vehicles

作　　者：李冬辉[1] 周大钧[1] 王伟[1] 

机构地区：[1]天津大学电气自动化与信息工程学院,天津300072

出　　处：《电力系统及其自动化学报》2017年第8期76-81,共6页Proceedings of the CSU-EPSA

摘　　要：电动汽车大量接入电网同一节点充电时容易造成节点无功不足。针对传统无功补偿器存在的问题,以及补偿器建设中造成的额外成本,提出采用电动汽车充电机在充电同时对网侧进行无功功率补偿的方法。在改进型充电机拓扑上,提出了无功电流动态采样法,通过延时与三角函数关系实时对无功电流进行采样。针对交流侧电感难以准确测量会影响控制精度,在常用的无差拍控制法基础上提出了预测型无差拍控制算法。最终简化了无功电流采样过程,同时对交流侧电感测量误差允许值增大,增强了系统鲁棒性。通过仿真与实验验证,该方法能够很好使得电动汽车补偿充电过程中自身及负荷吸收的无功功率,且电网电压电流正弦性良好。When a large number of electric vehicles（EVs）are connected to the same bus,a lack of reactive power will be caused.Considering the existing problem of traditional compensators as well as the extra cost due to the construction of compensators,a new method is proposed to compensate the reactive power in grid side using the charger during the charging process of EVs.Based on the topology of a modified charger,a dynamic reactive current sampling method is adopted,which can sample the reactive current realtime by using the time delay and triangular functions.Besides,to overcome the difficulty in accurately measuring the inductance value in AC side,which may affect the control accuracy,a predictive deadbeat control method is developed based on traditional deadbeat control method.Finally,the reactive current sampling process is simplified and the allowable error of the inductance value in AC side is expanded,which enhances the robustness of the system.Through simulations and experiments,it is verified that the proposed method can help the EVs compensate the reactive power for themselves as well as for the load resulting from the charging process,and the sine properties of the waveforms of voltage and current in grid side are also in a good state.

关 键 词：电动汽车 充电机 无功功率补偿 无功电流动态采样 预测型无差拍控制 

分 类 号：TM72[电气工程—电力系统及自动化]