An interleaved current-fed bidirectional full-bridge DC/DC converter for on-board charger

Abstract

An interleaved current-fed bidirectional full-bridge DC/DC converter for on-board Electric Vehicle (EV) charger is proposed in this paper. This proposed DC/DC converter interleaves two isolated full-bridge converters. In the forward direction power flow, it is an input-parallel output-series (IPOS) voltage-fed construct with the merits that low input current ripple and output voltage ripple. The IPOS construct can also decrease the current stress on the primary side devices and voltage stress on second side devices. In the reverse direction power flow, it is an input-series output-parallel (ISOP) current-fed construct with the merits low input voltage stress and low output current stress. It can realize zero current switching (ZCS) by second-side voltage clamping technique without snubber circuit. Moreover, the boost topology can decrease the turn ration of the transformer and lower the input current ripple. These merits make the bidirectional converter suitable for electric vehicles charging and driving mode. Operation equivalent circuits, analysis, simulation results are presented in this paper. A 3.3KW on-board EV charger prototype is built to demonstrate the validity of the proposed topology.