A battery power bank with series-connected buck-boost-type battery power modules

Abstract

The operation of a battery power bank with series-connected buck-boost-type battery power modules (BPMs) was investigated in this study. Each BPM consisted of a battery pack with an associated buck-boost converter for individually controlling battery currents. With a proposed discharging scenario, load voltage regulation with charge equalization among batteries was performed by controlling the battery currents in accordance with their state-of-charges (SOCs) estimated by real-time battery-loaded voltages detected under the same operating condition. In addition, the fault tolerance was executed to isolate exhausted or faulty batteries from the battery power bank without interrupting the system operation. Experiments were conducted to verify the effectiveness of the discharging scenario for a laboratory battery power bank with four series buck-boost BPMs.