A Single-Stage Series Resonance Dual-Active-Bridge AC–DC Converter With Wide Soft-Switching Range

In this paper, a novel single-stage isolated AC-DC converter is introduced to reduce the number of switching devices by sharing the active bridge of the interleaved totem-pole circuit with the secondary side of the bridge of a series resonant circuit. However, this configuration poses challenges in achieving zero voltage switching (ZVS) for AC-side switching. Concurrently, the reactive circulating current in the resonant tank of the series resonant circuit contributes to increased circuit losses. Therefore, a modulation scheme is proposed to realize the wide range ZVS of all switches in the grid voltage cycle while achieving a wider range of AC-DC conversion. Additionally, a minimum current optimization model is proposed to effectively minimize the circulating current in the resonant tank. Finally, a 1kW prototype is constructed to experimentally verify the theoretical analysis and assess the effectiveness of the proposed modulation scheme.