Battery charger with small DC-link capacitors for G2V applications

Abstract

In this paper, an AC/DC converter with a small DC-link capacitor for EV chargers is proposed, where a bridgeless PFC (power factor correction) boost rectifier and a full-bridge phase-shifted-modulated DC-DC converter are employed to transfer power from the grid to the electric vehicle. In order to solve the inherent problem of the second-order ripple power in a single-phase AC/DC converter, an auxiliary circuit is added, by which the DC-link capacitor can be reduced significantly. As a result, the bulky electrolytic capacitor can be replaced by a reliable film capacitor. The effectiveness of the proposed method has been verified by simulation results.