A Battery Strings Circulating Current Blocking Method for Battery Energy Storage Systems

Circulating current between paralleled battery strings within a Battery Energy Storage System (BESS) can significantly affect system efficiency, battery life, and safety. A circulating current blocking circuit and a corresponding control strategy for the BESS are proposed in this paper. It can block the circulating current during the charging mode, the discharging mode, the standby mode and the fault mode of the BESS. Simulation results validate the effectiveness of the proposed method.