多组乏锂电池并联运行在储能系统中的应用

从电动汽车上被替换的动力锂电池称作乏锂电池,在重新筛选分组之后可以继续用于具有平抑配网功率波动功能的储能系统中,但是这些电池容量衰减,内阻增大,充放电效率降低。通过对电池内阻特性以及锂电池的外特性的分析,提出了电压电流双环控制的多组乏锂电池并联运行的方法,提高储能系统配置容量和充放电效率,使乏锂电池在平抑功率波动上有更好的跟踪补偿精度。仿真和实验结果表明,多组乏锂电池并联运行可以提高乏锂电池充放电效率和功率平抑逆变器功率跟踪精度,验证了所提方法的可行性。

Application of Losing Partial Capacity Lithium Batteries of Parallel Operation in Energy Storage System

Power lithium batteries, which are replaced from electric vehicle, can be called losing partial capacity lithium batteries and be used in energy storage system with restraining fluctuant power in distribution network after being screened and grouped, but their capacities and charge-discharge efficiency become lower because of internal resistance being larger. So a method of losing partial capacity lithium Batteries of parallel operation based on double loops of voltage and current is proposed according to internal resistance characteristic and external characteristic of power Li-battery of losing partial capacity. Charge-discharge efficiency of losing partial capacity lithium batteries can be improved and better accuracy of power tracking can be obtained in the case of restraining fluctuant power. The results of simulations and experiments demonstrate that charge-discharge efficiency of losing partial capacity lithium batteries of parallel operation and accuracy of restraining fluctuant power can be improved, and the feasibility of the proposed method are validated.