微网环境下的电动汽车换电站运营策略

Operation strategy for battery swapping stations of electric vehicles in microgrid environment

包括分布式电源和电动汽车的微网通过内部优化运行,可以减小分布式电源的出力波动对电力系统的影响,这已被广泛认为是解决分布式电源接入系统的有效方法。电动汽车换电站由于可以避免车主长时间等待充电,已经成为大型城市发展电动汽车的主流模式。此外,换电站作为储能单元参与微网运行,可以提高微网接纳分布式能源的能力并改善微网运行的经济性。在此背景下,主要做了下述工作:(1)研究了换电站电池调度策略,制定了电池分组规则和调度优先级顺序;(2)分析了电池充放电状态并在满足车主用车需求和电池荷电量约束的前提下计算了换电站充电需求和最大充放电功率;(3)制定了以最大程度响应微网调度信号为目标的换电站电池调度流程。最后,采用包含分布式电源、电动汽车换电站和居民负荷的模拟微网系统来说明了所发展的模型与方法。

In a microgrid with renewable generation and electric vehicles （EVs）, by optimizing its operation, the nega- tive impacts of the power output fluctuation of distributed generation on the power system concerned can be mitigated, Which is deemed an effective solution for integrating distributed generation to the power system. Battery swapping re- presents a mainstream development mode of EVs, especially in large cities, since this more could efficiently reduce the waiting time for eharging batteries and hence motivate the wide employment of EVs. Acting as an energy storage device to participate in the optimalization operation of the microgrid, the battery swapping station enhances the ability of ac- commodating distributed renewable generation as well as achieve economical benefits. Given this background, some re- search work is earried out： （1） a dispatching stategy for battery swapping stations is proposed, and battery grouping rules and group priority defined; （2） charging/discharging states of batteries are analyzed, and considering the con- straints such as consumers＇ battery demands and battery charging states, the charging demand of the battery swapping station as well as its maximum charging/discharging power obtained; （3） the dispatching flowchart for the battery swapping station is developed with the objective of responding to the dispatching signals from the mierogrid to the grea- test extent. Finally, a sample mierogrid containing distributed renewable generation, a battery swapping station and res- idential loads is employed to demonstrate the developed model and method.