An Isolated Single-Phase AC-DC Converter based-on a Dual Active Bridge Converter and an Active Energy Buffer Circuit

This paper proposes a new isolated single-phase ac-dc converter for battery chargers of electric vehicles. The proposed battery charger consists of a front-end diode-bridge rectifier and a dual-active-bridge dc-dc converter including an active energy buffer circuit. The energy buffer circuit for power decoupling operation absorbs the power pulsation caused by the single-phase line into a small-rated capacitor by controlling its voltage. In this paper, a control sequence of the proposed converter has been explained to realize the power factor correction of the line current and the voltage control of the buffer capacitor. Experimental results verified the proposed power decoupling operation.