Design, simulation and performance analysis of two-stage power converter using totem-pole PFC and dual active bridge

Abstract

This thesis presents the design, modelling and performance evaluation of a 3.3 kW onboard electric vehicle charger based on a two-stage architecture consisting of a Totem-Pole Power Factor Correction (PFC) rectifier and a Dual Active Bridge (DAB) DC-DC converter. The target of this thesis is to achieve high efficiency and thermally reliable operation suitable for compact EV charging applications. Analytical modelling, semiconductor loss estimation, transformer and inductor loss calculations, and thermal analysis were performed using datasheet-based semiconductor equations alongside detailed MATLAB/Simulink simulation. Analytical results predicted efficiencies of 99% for the Totem-Pole PFC and 96% for the DAB stage while simulation results validated the analytical trends achieving 99% efficiency for the PFC and 94% for the DAB converter. The Totem-Pole PFC and DAB stage exhibited a total device loss of 41 W and 121 W respectively. The thermal evaluation showed junction-to-case, case-to-sink and sink-to-ambient temperature rises of 6.7℃, 2.1℃ and 1.5℃ respectively, resulting in a maximum junction temperature of 50.3℃ at 40℃ ambient. The results confirm that the proposed topology meets efficiency and thermal requirements, demonstrating suitability for high-performance EV charging applications.