Abstract：When the battery is used under the condition of high rate pulsed discharge, its parameters change largely and it is hard to estimate its state of charge (SOC) accurately. To solve the problems, taking LiFePO4 battery as the research object, firstly, based on the second-order RC equivalent circuit model, recursive least square algorithm is adopted to identify the parameters dynamically, thus a time-varying parameter model is built. Secondly, the process equation and measurement equation of the battery are established. Finally, the square-root cubature Kalman filter algorithm is used to realize the SOC estimation of the battery. This SOC estimation algorithm can not only adapt to the parameter change of the model, but also correct the initial error. Experiments indicate that, under the condition of high rate pulsed discharge, the time-varying parameter model can simulate the variation of terminal voltage accurately, and the SOC estimation algorithm can ensure high accuracy even if the initial value has a large error.
张振宇, 汪光森, 聂世雄, 邢鹏翔. 脉冲大倍率放电条件下磷酸铁锂电池荷电状态估计[J]. 电工技术学报, 2019, 34(8): 1769-1779.
Zhang Zhenyu, Wang Guangsen, Nie Shixiong, Xing Pengxiang. State of Charge Estimation of LiFePO4 Battery under the Condition of High Rate Pulsed Discharge. Transactions of China Electrotechnical Society, 2019, 34(8): 1769-1779.
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2019, Vol. 34 
