A Novel Zero-Voltage-Switching On-Board EV Charger

Abstract

For EV onboard charging, high power density of the charger is required. Soft switching technique is an effective way to increase On-Board Charger (OBC) power density and efficiency. This paper presents a novel OBC topology which can realize Zero-Voltage-Switching (ZVS) of all the power semiconductor devices in the circuit. An auxiliary resonant branch is used to realize Zero-Voltage-Switching for both front¬end full-bridge rectifier and phase-shift full-bridge dc-dc converter. A novel PWM scheme is proposed. According to stage analysis, ZVS conditions are derived. Finally, the proposed OBC is verified by the experiment.