锂离子电池自由成组分层均衡技术研究

Research on Hierarchical Equalization Technology of Li-ion Battery Pack With Free Combination

为改善当前锂离子电池组均衡管理系统存在的均衡速度慢、均衡时间长等问题,提出了一种以电感作为中间储能元件的自由成组分层均衡技术。详细介绍了该均衡电路的结构布局和工作原理,并且以单体电池(子电池组)端电压作为均衡变量制定了相应的均衡策略,实现系统内每一层均衡器同时进行均衡。最后,通过搭建Matlab/Simulink仿真模型和硬件实验平台对单层和分层两种均衡电路进行对比分析。以四节单体构成的锂电池组进行实验,结果表明自由成组分层均衡电路能够缩短约24.71%的均衡时间。

In order to improve the problems of slow equalization speed and long equalization time in the equalization management system of the Li-ion battery pack,a free combination hierarchical equalization technology with inductors as the intermediate energy storage element is proposed.The structure layout and working principle of equalization circuit are introduced in detail and the corresponding equalization strategy is formulated with the terminal voltage of the single battery(sub battery pack)as the equalization variable.The whole system can realize simultaneous equalization of each layer.Finally,by building Matlab/Simulink simulation model and hardware experiment platform,the single layer scheme and the hierarchical scheme are compared and analyzed.Taking Li-ion battery pack as the research object which composed of four single batteries,the results show that the free combination hierarchical equalization circuit can shorten the equalization time by about 24.71%.