基于Thevinin的锂离子动力电池建模实验研究

Experimental Research on Modeling of Lithium Power Battery based on Thevinin

摘要:

为了准确估算锂电池的荷电状态(SOC),对其等效电路模型进行了研究。通过充放电实验研究锂电池的电特性,利用充放电电压、电流数据辨识其欧姆内阻、极化内阻和极化电容参数,建立了较为精确的锂电池Thevenin模型。建立实验用磷酸铁锂电池的离散状态空间模型,在Matlab/Simulink环境下建立了该电池的仿真模型,并设计了放电实验。实验证明,建立的锂电池模型仿真数据与实测数据误差小于0.1 V,且随着充放电的进行误差逐渐减小,较好的跟随电池电压的变化,模型精度较高。

Abstract:

To accurately estimate the state of charge (SOC) of lithium battery, the equivalent circuit model was studied. Through experimental study on the electrical characteristics of lithium-ion batteries to charge and discharge, use of charging and discharging voltage and current data to identify the ohm internal resistance, polarization resistance and capacitance parameter, more precise lithium battery Thevenin model was established. In this paper, a discrete state space model of lithium iron phosphate battery was established and the simulation model of the battery was established in Matlab/Simulink environment, and the discharge experiment was designed. Experiments show that the mathematical models of lithium batteries simulation data and the measured data error is less than 0.1V, and the error decreases as the charge and discharge, better to follow the change of the battery voltage, the model precision is higher.