电动汽车动力电池组SOC均衡控制算法仿真

采用当前算法均衡控制电动汽车动力电池组的SOC(电池荷电状态)时,得到电动汽车动力电池组SOC估计值与实际值之间的误差较大,并且存在SOC估计精准度低和控制效果差的问题。提出电动汽车动力电池组SOC均衡控制算法,建立电动汽车动力电池组的Thevenin等效电路模型,在Thevenin等效电路模型的基础上采用扩展卡尔曼滤波算法估算电动汽车动力电池组的SOC,引入标准差判断电动汽车动力电池组的工作状态,根据判断结果对电动汽车动力电池组SOC进行均衡控制。仿真结果表明,所提方法估算SOC的精准度较高、均衡控制效果好,均衡控制后电动汽车动力电池组的容量利用率较高。

Simulation of SOC Equilibrium Control Algorithm for Electric Vehicle Power Battery Pack

When the current algorithm is used to equalize the state of charge(SOC) of electric vehicle power battery pack, the error between the estimated value of SOC and the actual value of electric vehicle power battery pack is too large, resulting in low precision of SOC estimation and poor control effect. Therefore, an algorithm of SOC equilibrium control for electric vehicle power battery pack was put forward. Firstly, Thevenin equivalent circuit model of electric vehicle power battery pack was built. Based on Thevenin equivalent circuit model, the extended Kalman filter algorithm was used to estimate the SOC of electric vehicle power battery pack. Secondly, the standard deviation was adopted to determine the working state of electric vehicle power battery pack. According to the judgment results, the SOC of electric vehicle power battery pack was equalized and controlled. Simulation results show that the proposed method has high precision of SOC estimation and good equilibrium control effect. Meanwhile, the capacity utilization ratio of electric vehicle power battery pack after equilibrium control is higher.