A high-frequency, high-efficiency silicon carbide based phase-shifted full-bridge converter as a core component for a high-density on-board vehicle battery charging system

This paper presents a phase-shifted full-bridge (PSFB) converter that utilizes silicon carbide (SiC) power devices to achieve a high-density and high-efficiency solution for isolated dc-dc converter applications. Specifically, this converter represents a core technology for a Level 2 on-board vehicle battery charger for applications in electric vehicles (EVs) and plug-in hybrid electric vehicles (PHEVs). The operation of the circuit topology is discussed along with the advantages gained through the use of SiC power devices. Design equations for the power stage components are presented. Expected performance is validated via a hardware prototype, where a peak efficiency of 93.4% is obtained at a switching frequency of 500 kHz. The switching frequency is then reduced to optimize the converter efficiency and an overall peak efficiency of 96.5% is measured at 200 kHz. A peak output power of 6.06 kW results in a volumetric power density of 12.0 kW/L and a gravimetric power density of 9.1 kW/kg.