考虑电池运行状态的改进安时积分法

Improved Ah integration method considering the operation state of battery

准确估计电池的荷电状态(SOC)是保障电池储能系统(BESS)安全稳定运行的前提。针对传统安时(Ah)积分法忽略充放电状态,导致SOC估计精度降低的问题,基于充放电状态对电池效率和最大可用容量的影响实验,得到不同充放电倍率下SOC与电池效率的关系、充放电倍率与电池最大可用容量的关系,提出考虑电池运行状态变化的改进Ah积分法,以提升SOC估计精度。在不同运行工况下,进行电池SOC估计对比发现,在不同环境温度下,所提Ah积分法的估计误差均最小,25℃时的最大误差仅为0.346%,比优化Ah积分法和传统Ah积分法分别提升0.142和0.527个百分点。

Accurately estimating the state of charge(SOC)of batteries was a prerequisite to ensure the safe and stable operation of battery energy storage systems(BESS).Aiming at issues of the traditional ampere-hour(Ah)integration method ignored battery charge and discharge state which reduced SOC estimation accuracy,the relation between SOC and battery efficiency at different charging and discharging rates and the relation between the charging and discharging rates and the maximum acceptable capacity of batteries were obtained based on the influence experiments of different charging and discharging states of batteries on battery efficiency and maximum acceptable capacity.An improved Ah integration method considering the variation of battery running state was proposed to improve the SOC estimation accuracy.The comparison of battery SOC estimation under different operating conditions showed that the estimation error of Ah integration method proposed at different ambient temperatures was the smallest,the maximum error at 25℃was only 0.346%,which was 0.142 and 0.527 percentage points higher than that of optimized Ah integration method and traditional Ah integration method,respectively.