A Two Switch Multiport Non-Isolated DC-DC Converter for On-Board EV Charging Application

Abstract

This paper proposes multiport DC-DC converter for on-board charger (OBC) EV applications with simultaneous charging of high voltage (HV) battery and low voltage (LV) battery. The evolution of this converter involves replacing the switch found in a conventional step-up converter with a pair of series-connected switches. This arrangement allows for an additional switch node that generates a LV output. the proposed converter has benefits of high voltage gain for HV side, continuous input current, a reduced switching count, regulation of two battery voltages with two switches. Moreover, the inherent shoot-through protection enhances the converter's reliability. The proposed converter exhibits same working principle as that of conventional boost and buck converters. Consequently, the control system methodology remains consistent with that of separate converters, ensuring precise regulation of each output. The working principle, design analysis is discussed. To validate the theoretical analysis, detailed simulation results are presented. © 2024 IEEE.