Abstract: Due to the production and operation conditions of electric vehicle power battery pack, the battery quantity in the battery pack is inconsistent, resulting in a series of problems such as reduced battery life and increased safety risk. This paper proposes a multi-layer equalization scheme based on the traditional inductive active equalization scheme. In this scheme, the first layer takes the battery state of charge (SOC) as the equalization parameter, and the upper layer takes the battery operating voltage as the equalization parameter. The energy transfer between battery packs is achieved through the comprehensive effect of the multi-layer equalization system. On the basis of the scheme, eight batteries were taken as examples to establish a Simulink simulation model and carry out constant current charging, static and constant discharge three simulation tests. Through the simulation test, the SOC of each battery in the above three working conditions tends to be consistent over time. The simulation results show that the scheme can effectively complete the energy transfer task under charging, static and discharge conditions, and balance the electric energy of the battery pack, which confirms the effectiveness of the scheme.

Key words: Electric vehicle; Battery equalization control; Active equalization; Modeling and simulation; Battery SOC

摘要： 电动汽车动力电池组由于生产和运行工况等不同，会使组内电池的电量不一致，进而 造成电池组使用寿命降低、安全风险增大等一系列问题。论文针对这些问题，在传统电感主 动均衡方案的基础上提出了一种多层均衡方案。这种方案第一层以电池荷电状态（SOC）为 均衡参数，高层则以电池工作电压为均衡参数，通过多层均衡系统的综合作用来达到电池组 间的能量转移。在该方案的基础上，以八个电池为例建立了 Simulink 仿真模型，并进行恒流 充电、静置和恒流放电三个工况的仿真测试。经过仿真测试，在上述三种工况中各电池的 SOC 随着时间会逐渐趋于一致。仿真结果表明，该方案在充电、静置、放电工况下都能有效完成 能量转移任务，对电池组进行了电能的均衡，证实了该方案有效性。

关键词: 电动汽车；电池均衡控制；主动均衡；建模仿真；电池 SOC