基于V2G技术的电动汽车充电器分层控制策略

Hierarchical Control Strategy for Electric Vehicle Charging Station Based on V2G Technology

为解决车网互动时电动汽车(EV)深度充放电损害电池及直流微电网功率变化引起的母线电压波动问题,提出一种基于车对网(V2G)技术的EV充电器分层控制策略。控制策略采用一次控制、二次控制双层模式。一次控制层基于电动汽车荷电状态(SOC)的改进下垂控制,实现EV之间的荷电平衡;二次控制层引入包含EV输出电压和功率信息的状态因子λ,控制器通过局部计算生成电压补偿项修改充电器的参考输出电压,实现快速地功率均分和直流母线电压平衡。通过Matlab/Simulink软件搭建相应的仿真模型,验证了所提出控制策略的可行性和有效性。

In view of vehicle to grid(V2G),targeting the problems of battery damage caused by the deep charging and discharging of electric vehicle(EV)and the bus voltage fluctuation caused by the power change in DC microgrid,the paper proposes a hierarchical control strategy with primary control and secondary control for EV charging station based on V2G technology.The primary control layer is used to achieve the charge balance between EVs based on the improved droop control of the state of charge of EV.The secondary control layer introduces the state factorλincluding EV output voltage and power information.The controller generates voltage compensation by local calculation to modify the reference output voltage of the charging station,realizing rapidly power equalization and DC bus voltage balance.The corresponding simulation model is built on Matlab/Simulink to verify the feasibility and effectiveness of the proposed control strategy.