A Compact Two-Stage Power Converter for Flexible Multiple-Battery Charging

摘要

In this paper, a modified converter topology is proposed to reduce battery charging system cost and enhance flexibility. The proposed system is interfaced to the grid with an H-bridge converter and the DC rails voltage is separated into upper and lower two parts by employing a de-voltage divider. Then, DC rails are connected to another isolated DC link through dual active bridge converters (DABs). In this proposed system, since the employment of voltage divider and the coordinated phase-shifting control of DAB converters, each DC links voltage can be regulated independently to meet with the battery control requirements without any noticeable interference. At the same time, the sinusoidal grid current is guaranteed in different cases. Simulated results are provided to validate the correctness of the proposed topology and corresponding control strategy.