Charge equalization of battery power modules in series

Abstract

Battery power modules (BPMs) with associated power converters are connected in series to comply with a high load voltage. With bidirectional power converters, BPMs can perform buck conversion for the charging operation. The continuous conduction mode (CCM) and the discontinuous conduction mode (DCM) of buck converters in series are analyzed. According to the analyzed results, an equalization strategy is proposed to solve the charge imbalance problem by scheduling the individual battery current. Experiments are carried out to demonstrate the effectiveness of the balance charging method.