混合动力汽车电池管理系统SOC估算策略

SOC estimation strategy of BMS for HEV

电池荷电状态(state of charge,SOC)是电池管理系统的重要参数,也是混合动力汽车动力系统分配的重要依据,准确地估算电池荷电状态具有重要意义。按照传统电量状态定义电池SOC的估算方法不能满足蓄电池变电流放电工况的需求,为了解决这一问题,采用能量守恒原理对电池SOC重新定义,基于修正的Thevenin等效电路,在Matlab/simulink环境下,建立了电池的动态充、放电模型,通过仿真分析,证明新的SOC估算策略能够满足蓄电池在大电流和变电流放电工况下SOC的估算,提高了电池SOC估算的精度。

State of charge（SOC） is an important parameter of the battery management system,and it is also the distribution basis of hybrid electric vehicle power system,therefore,the correct estimation of SOC is very important.The traditional estimation strategy of SOC is not suitable for the conditions of variable discharge current of the battery,and consequently a new estimation strategy of SOC was presented based on the law of conservation of energy.Based on the modified Thevenin equivalent circuit,a battery of dynamic charge and discharge models were established.The simulation results show that the new estimation strategy of SOC is competent for the conditions of large and variable discharge current,and improves the precision of the battery SOC estimation.