A soft switching current fed bidirectional isolated three-phase DC-DC converter

Abstract

A soft switching current fed bidirectional isolated three-phase dc-dc converter based on a voltage source dual-active bridge (DAB) topology is presented in this work. Current fed structures have more flexibility to ensure soft switching for a wide operating range, when compared with voltage source topologies, because the variable duty cycle allows maintain a dc link constant between the primary and secondary sides of the converter. Details and description of the proposed converter are presented. A mathematical analysis is realized regarding the power flow behavior and the switching characteristics of the topology. Simulations results considering a design example rated at 48V/380V, 3.5kW are performed to validate the proposed approach.