Variable Switching Frequency Control for a Dual-Active-Bridge Single-Phase AC-DC Converter with Active Energy Buffer

Abstract

This paper proposes a novel control method for a dual-active-bridge (DAB) single-phase AC-DC converter with an active energy buffer circuit. The proposed control method realizes continuous-current-mode (CCM) operation of the DAB converter by adjusting the switching frequency according to the phase angle of the single-phase AC-line voltage; thereby improving the power conversion efficiency. Experimental results verify the CCM operation with the proposed control method and demonstrate an improved power conversion efficiency of 92.8% for a 220-V, 5.4-kW output.