不同放电倍率下锂电池SOC估算分析研究

The Analysis of Lithium Battery SOC Estimation Under Different Discharge Rate

电动汽车作为新型节能环保的交通工具之一,以常用磷酸铁锂电池为研究对象,分析电池欧姆内阻是否对荷电状态(State of Charge,SOC)的估算存在影响。通过不同放电倍率的混合脉冲功率特性(Hybrid Pulse Power Characteristic,HPPC)实验对电池欧姆内阻进行了分析和辨识,并提出了一种实时修正欧姆内阻的原理和方法,以建立等效电路模型和滤波算法方法实现了在不同放电倍率下的SOC估算,报告了不同放电倍率下欧姆内阻对估算SOC及汽车容量信息显示存在影响的现状。研究结果表明,电池欧姆内阻对SOC估算及电动汽车剩余容量信息的显示具有直接的影响。

Electric vehicle as one of the new transport in energy saving and environmental protection,and using conventional lithium iron phosphate as the research object,and analyzed whether the ohmic resistance of the battery has affect on State of Charge（SOC）estimation. Through the different discharge rate of Hybrid Pulse Power Characteristics（HPPC）experiments analyzes and identifiesthe ohmic resistance of the battery,and proposes a real-time correction principle and method of ohmic resistance,and then,with the method of creating equivalent circuit model and filtering algorithm having achieved the estimation of battery＇s SOC under the different discharge rate,finally it reportsthat the status of ohmic resistance has existed theinfluence on SOC estimation and the display of vehicle capacity information. At last,the result shows that,the ohmic resistance of battery has a direct impact on the SOC estimation and the display of residual capacity of electric vehicle information.