A Novel Battery Equalization Method Base on Fuzzy Logic Control Considering Thermal Effect

Abstract

In order to avoid battery over-charges and over-discharges and improve the battery pack capacity, a passive equalization controller based on fuzzy logic control (FLC) is proposed to reduce the impact on inconsistency in manufacture and use processes of battery pack. A cell's state of charge (SOC) difference and its temperature is chosen as the FLC's input and the balance current is chosen as the FLC's output. The advantage of this FLC is can reach a larger balancing current and control the batteries temperature at the same time compare with average SOC controller and switch controller. Simulation results show that the equalization strategy based on FLC can achieve battery pack balance in a shorter time in a lower finish temperature. This equalization strategy can provide battery management system (BMS) designer a higher performance control strategy on the basis of the existing hardware platform.