A single-stage variable output AC-DC converter with PFC and soft-switching for renewable energy integration

Abstract

This study introduces a versatile variable-output isolated AC-DC converter design distinguished by its incorporation of soft-switching and a novel control algorithm. The converter configuration comprises two full-bridge diode rectifiers, positioned at both input and output sides, complemented by a full-bridge isolated resonant DC–DC converter. By providing soft-switching across all semiconductor components, the proposed design could achieve a significant power density increase while still preserving the power conversion efficiency in an acceptable range. The novel control algorithm concurrently governs power factor and output voltage, employing the duty cycle as the primary control variable and the phase shift as an auxiliary parameter. Using this synergistic method fulfills more efficiency, increases power density, and improves power factor performance. The effectiveness and reliability of the converter were carefully confirmed by experiments done on a prototype, which provided the capacity to provide over 400 watts in its maximum state of operation. Notably, the converter's adaptability makes it an ideal candidate for a wide variety of applications, with a specific emphasis on integrating renewable energy sources into power systems.