基于效率优化的锂电池组均衡系统研究

Research on balance system of Li-ion battery module based on efficiency optimization

锂离子动力电池系统是新能源汽车“三电”系统之一,针对锂离子电池成组之后出现的不一致性问题,设计了一种新型主动均衡系统。借助有向图思想对传统均衡电路进行分析,结合传统均衡结构的优点,提出了一种多级双向有源均衡拓扑;利用模糊控制设计智能控制策略,根据锂离子电池状态参数动态调节均衡电流,对均衡过程的时间效率与能量效率进行优化。使用Matlab/Simulink搭建仿真模型,并与传统主动均衡结构进行对比仿真。结果表明,该主动均衡系统可实现高精度的均衡目标,改善均衡效率,延长电池寿命。

Li-ion power battery system is one of the "three power" systems of new energy vehicles. In view of the inconsistency of Li-ion battery after grouping, a new active balance system was designed. The traditional equalization circuit was analyzed based on the graph theory and a multi-level bidirectional active equalization topology combined with the advantages of traditional equalization structure was proposed. The fuzzy control was used to design control strategy, which could adjust the equalization current dynamically according to the battery state, so that the time efficiency and energy efficiency of the equalization process was optimized. The simulation model was built using Matlab/Simulink. Compared with the traditional equalization method, the results show that this system can achieve high precision equalization targets, improve the equalization efficiency and prolong the battery life.