计及电池老化的电动汽车储能频率响应控制

摘要

电动汽车入网后,不仅可以作为可控负荷充电,还可以作为分布式储能单元为电网提供辅助调频服务.在满足电动汽车用户充电需求的基础上,充分考虑储能电池循环充放电老化容量的衰减和可接受功率能力的降低,提出了一种计及电池老化衰减的电动汽车储能频率响应控制策略.该控制策略量化分析了电动汽车锂电池老化过程中容量衰减和功率能力变化,精确估计电池储能状态SOC,实时更新电池可接受最大充放电功率,有效避免了辅助调频过程中荷电状态超限和充放电倍率过大对电池造成的不利影响.通过算例分析验证了所提电动汽车储能频率响应控制策略为电网提供辅助调频服务时,在满足用户充电需求的前提下,有效地减缓了电动汽车动力电池寿命的衰减.%Numerous EVs have been integrated in power grid, which will not only can be used as controllable load charging, but also can be used as a distributed storage unit to provide auxiliary service.Frequency response control strategy of EV distributed storage is proposed considering aging of battery, which has been rarely discussed by researchers.This strategy can satisfy the individual demand of users and SOC constraints, and avoids exceeding the state of charge limit or damaging the battery caused by the large charge-discharge current.A simulation study is carried out to demonstrate the electric vehicle for frequency regulation as mobile energy storage unit.The simulation results showed that control strategy of distributed storage greatly suppressed system frequency deviation, mitigating ageing of EV power battery.