基于Buck-Boost准谐振电路的电池自适应分组均衡方案研究

Research on Battery Adaptive Grouping Equalization Scheme Based on Buck-Boost Quasi-resonant Circuit

针对Buck-Boost均衡电路中开关频繁通断导致均衡效率降低的问题,文中对传统的Buck-Boost电路进行改进,设计可实现开关管的零电压导通的准谐振电路,有助于减小开关损耗,提高均衡电路的效率。为减少开关管的通断次数,并缩短均衡时间,均衡策略采用全局优化视角,分段选择电压和SOC作为目标均衡变量,并提出电池单体间、单元间及模组之间的自适应分组均衡策略。以8个电池串联的电池组为例,设计静置、充电、放电和浮充均衡实验,结果表明,与传统方案相比,提出的均衡电路和均衡策略在均衡效率和速度上有显著提升,可助力电池组的整体性能提升及其延寿。

The frequent make-and-breaks of the switches in the Buck-Boost equilibrium circuit could reduce the equalization efficiency;on this basis,the traditional Buck-Boost circuit is improved and a quasi-resonant circuit that can realize the zero-voltage conduction of the switch tube is designed,which is conducive to reduce the switching loss and improve the efficiency of equalization circuit.Aiming to reduce the number of switch make-and-breaks and shorten the equalization time,the equilibrium strategy from the global optimization perspective is adopted,the voltage and SOC are selected as the target balancing variables in sections,and the adaptive grouping equilibrium strategies for inter-monomers,inter-cells and inter-modules are proposed.Taking the battery pack with 8 batteries connected in series as an example,an equilibrium experiment is conducted for quiescence,charging,discharging and floating charge.The results show that the equilibrium circuit and the equilibrium strategies proposed in this paper can significantly improve the equilibrium efficiency and speed compared to the traditional scheme,which can help improve the overall performance and prolong the service life of the battery pack.