Topology Comparison and Selection of a Single DC/DC Converter Stage for High-Efficiency Power Conversion Circuit for Peltier-Driven Household Refrigerator

This paper presents a comparative analysis of power conversion topologies to reduce stages and improve efficiency in Peltier-driven household refrigerators. Conventional architectures typically employ a multi-stage structure consisting of a PFC stage, an LLC resonant converter, and a Buck converter. While providing flexible control, this approach increases power loss and component count. To address these limitations, four single-stage isolated topologies—Phase-Shifted Full Bridge (PSFB), Asymmetric LLC, Active-Clamp Forward (AC Forward), and Active-Clamp Flyback (AC Flyback)—are evaluated under identical conditions through simulation. The results indicate that the AC Forward topology provides balanced efficiency over the entire load range. Based on this, an AC Forward-based power conversion system is implemented. Experimental results confirm improved efficiency compared with the conventional LLC–Buck architecture while significantly reducing power components.