Design of Bi-Directional Vehicle Charger for High Efficiency New Energy Vehicle

Abstract

At present, the new energy vehicle industry is developing rapidly, in order to improve the charging power and efficiency of bi-directional on-board charger, the power factor correction circuit and CLLC resonant converter are cascaded together. The variable DC bus voltage scheme is adopted, and the PFC provides a wide range of DC bus voltage. The CLLC resonant converter works near the resonant point. The switch is made of silicon carbide, which greatly improves the charging and discharging efficiency. Finally, bidirectional on-board charger with a maximum charging power of 11kW and a maximum discharge power of 6.6kW is built and tested. The results show that the maximum efficiency of 11kw/6.6kw charging mode can reach 95.62% and 95.05% respectively, and the maximum efficiency of 6.6kw discharge mode can reach 95.18%.