Series Operation Method of 3-Phase Current-Fed Dual Active Bridge Converter for Battery Pack Charging/Discharging Systems

A study on parallel operation has been conducted in the previous study on battery pack charging/ discharging system, but few studies have been made on serial connection. Due to the characteristics of the battery charging and discharging application in series, the master module controls the battery current, and the slave module controls the output voltage of each module. However, this control method causes unbalance of the output voltage of each converter module, which may cause deterioration and damage of some converter modules. Therefore, in this paper, we proposed a series control method of 3-Phase CurrentFed Dual Active Bridge (3P-CFDAB) Converter that can solve the output voltage unbalance between modules during series operation. The proposed control technique was verified through PowerSIM simulation and experiment