电池组用荷电状态均衡充电模糊控制策略

Fuzzy Control Strategy for Battery Equalization Charge Based on State of Charge

研究了一种电动汽车用磷酸铁锂动力电池组分布式主动均衡充电系统。该系统给单体电池分别配备了反激变换器均衡充电子模块和电池管理子模块,通过嵌入自适应卡尔曼滤波算法到电池管理均衡控制单元,完成单体电池荷电状态的实时估计。利用模糊控制策略,调节各均衡充电子模块的输出电流;与平均法均衡控制策略相比,使用的模糊控制策略能明显缩短均衡时间,降低电池组之间的不一致性。为验证所研究的均衡充电控制策略,对48 V/140 Ah磷酸铁锂动力电池组展开了充电模式下的系统均衡实验,实验结果验证了控制策略的有效性。

A novel distributed active equalization charging system was investigated,which was applied to the electric vehicles using lithium iron phosphate dynamic battery pack. It consists of flyback converter equalization charging sub- module and battery manage sub-module for each single battery. By means of embedding adaptive Kalman filter algorithm in each battery manage sub-module, it can complete detect the state of charge of single battery. According to the studied fuzzy logic control strategy, the converter achieves the adjustment of the output current of each battery charging equalization unit. Compared with the average method equalizer control strategy, the strategy can significantly reduce the equalization time and the performance difference between the series-parallel group. At last,to verify the studied equalization charge control strategy, the 48 V/140 Ah lithium iron phosphate battery pack system equilibrium test is carried out based on charing mode. Experimental results show the effectiveness of the control strategy.