应用于储能单元的串联电池模块主动均衡研究

Research on active equalization for series connected battery module used in battery energy storage systems

串联电池组广泛应用于电动汽车和储能电站等多个领域。在长时间使用后,电池单体由于制造工艺和使用环境的差异容易出现电量的不均衡,影响电池组整体容量和功率性能的发挥。为此,针对储能单元电池模块提出了一种双向主动均衡系统,该系统包含串联电池模块、开关阵列、主动均衡DC/DC变换器、电池信息采集单元等。对均衡主电路基本工作原理及控制过程进行了分析,利用16节电池串联构成的电池模块在构建的均衡实验平台上进行了双向电量均衡实验验证,均衡结果表明,初始最大SOC差异40%的电池组经过均衡后SOC最大相差1.1%,证明了均衡系统的有效性。

Series connected batteries are widely used in many fields such as electric vehicles and energy storage stations.The power and capacity performance of battery pack declines after long-term operation,owing to the differences in manufacturing process and operating environment.Therefore,a bidirectional active equalization system is proposed for the series connected battery module of the energy storage system.The system includes series connected battery module,switch array,active equalization DC/DC converter,battery information acquisition unit,etc.The basic working principle and control process of the equalization circuit are analyzed.The bidirectional equalization experiments are carried out on a battery pack built by 16 batteries.The equalization results show that the maximum SOC difference is reduced from 40%to 1.1%after equalization,which proves the feasibility and effectiveness of the equalization system.