基于参数分析的蓄电池模型健康状态估计

Health State Estimation of Battery Model Based on Parameter Analysis

为了及时、准确地评价蓄电池的老化水平,保证其应急放电时刻的输出性能,基于备用蓄电池组定期维护放电阶段的背景,对蓄电池健康状态(SOH)的估计方法进行研究。首先,利用仿真试验,验证了可较好反映其内部特性的二阶RC电路模型作为蓄电池模型的合理性以及模型参数辨识的准确性。然后,通过对同一型号铅酸蓄电池进行老化试验,分析蓄电池模型参量关于维护放电后荷电状态(SOC)值和蓄电池当前SOH值的关系,建立蓄电池定期放电维护(额定容量的20%)后的欧姆内阻R_(0)与SOH的关系,实现蓄电池SOH的定量估计。试验结果表明:在SOH值衰减至80%之前,该方法估计得到蓄电池SOH值较定义法获取SOH值的偏差在3%左右,说明该方法可以很好地实现蓄电池SOH的估计。准确的SOH值可以为多参数评价法实现蓄电池组一致性评价奠定数据基础。

In order to evaluate the aging level of battery timely and accurately and ensure the output performance of emergency discharge,the estimation method of battery state of health(SOH)is studied based on the periodic maintenance of spare battery pack.Firstly,the rationality of the second-order RC circuit model which can reflect the internal characteristics of battery is verified by simulation experiment and the accuracy of model parameter identification is verified.Then,through the aging experiment of the same type of lead-acid battery,the relationship between state of charge(SOC)value and current SOH value of battery is analyzed,and the relationship between R_(0) and SOH value of battery after periodic maintenance of battery discharge to 20%of rated capacity is established to realize the quantitative estimation of battery SOH.The results show that before the SOH value decays to 80%,the deviation of the SOH value estimated by this method is about 3%of the value obtained by the definition method.The accurate SOH value can lay a foundation for the realization of battery consistency evaluation by multi-parameter evaluation method.