In order to realize active equalization of 48 V mild hybrid battery pack, and improve energy utilization rate, firstly the group design and consistency check of 48 V mild hybrid system battery of a vehicle were conducted, then the topological structure of the active equalization circuit was determined, and then the equalization opening threshold and equalization control strategy of active equalization circuit were designed based on the information of the battery terminal voltage collected by the BMS. The results of simulation analysis indicate that the State Of Charge (SOC) bias errors of the battery module after active equalization does not exceed 0.005.

48 V battery system  /  Battery Management System (BMS)  /  Active equalization  /  Fuzzy control