Charging Scenario of Serial Battery Power Modules with Buck-Boost Converters

This paper studies the charging scenario of the battery power bank with buck-boost battery power modules (BPMs) connected in series. For the BPMs with serial connection, the charging currents to batteries can be individually scheduled by adjusting the duty-ratios of the associated power converters. During the charging process, those batteries having been completely charged can be isolated from the battery power bank without interrupting the charging operation. To fully utilize the available charger's capacity, a simple charging scenario is proposed according to the state-of-charges (SOCs) of the batteries under the limitations of the allowable charger's power and the maximum battery charging current. Experiments carried out on four buck-boost type BPMs have confirmed the efficient performance of the charging scenario.