Expanding ZVS range for dual active bridge DC-DC converter using three-level neutral-point-clamped inverter topology

This paper discusses an expansion method of zero voltage switching (ZVS) operation range in a dual active bridge (DAB) dc-dc converter using a three-level neutral-point-clamped (NPC) inverter topology. A DAB converter consists of two active bridges connected through a high-frequency transformer. A drawback of a conventional DAB converter is that ZVS operation range is limited. This paper presents a novel control strategy for the proposed DAB converter using a three-level NPC inverter to expand the range of the conventional ZVS operating mode. In addition, the effectiveness of the proposed scheme for the DAB converter is verified through simulations and experiments.