基于电路暂态分析的功率型动力电池建模

Modeling research of power-assist battery based on circuit transient analysis

以混合动力汽车用8Ah功率型锰酸锂电池为对象,选取戴维南电路模型等效开路电压、欧姆内阻和极化阻抗,在室温25℃条件下,分充电方向和放电方向的不同开展建模研究.通过增加放电搁置时间将复合功率脉冲试验进行改进,复合脉冲试验数据采用电路暂态分析和最小二乘的方法辨识,得到极化阻抗时间常数τ,不同充放电方向和不同SOC点的电路元件参数,利用Matlab/Simulink工具建立了电池仿真模型,并采用HPPC试验和变电流试验数据对仿真模型进行了验证.仿真结果表明等效电路模型具有较高的精度,能够准确地模拟锰酸锂电池的动态特性.

With an 8Ah power-assist Li-ion battery for hybrid vehicles as the research object,this paper uses Thevenin equivalent circuit model to simulate the open-circuit voltage,ohmic resistance and polarization resistance,and the charging/discharging models are studied at the temperature 25 ℃.By increasing the discharge standing time to improve Hybrid Pulse Power Characterization（HPPC） test,least square method and circuit transient analysis are used to identify parameters.The polarization resistance’s time constant τ and element parameters of charging/discharging tests are obtained at each SOC point.Matlab/Simulink is used to build a battery simulation model which is validated by the data of HPPC test and change-current test.The simulation results show that the Thevenin equivalent circuit model has a high accuracy,and it can simulate the dynamic characteristics of lithium manganese oxide battery accurately.