Comparison of Battery Degradation and Power Losses Under Different SoC Balancing Methods in Cascaded H-Bridge Converter-based BESS

In cascaded H-Bridge converter-based battery energy storage systems (CHB-BESS), inter-submodule state-of-charge (SoC) balancing is required to achieve full BESS capacity utilization. Multiple SoC balancing methods have been proposed for this purpose, trying to maximize the SoC balancing speed. However, the effect that they have on the lifetime of the CHB-BESS batteries and its power losses has not been studied, which could help obtain a more durable, reliable and efficient system. Consequently, this paper compares several CHB-BESS SoC balancing methods in terms of the degradation they induce in the batteries and the power losses they generate.