An AC-DC Single-Stage Full-Bridge Converter With Improved Output Characteristics

A new auxiliary circuit for an ac-dc single-stage power-factor-corrected (SSPFC) full-bridge-type converter is proposed in this paper. The new auxiliary circuit is simple, handles low power, and is active only when the converter is operating under light load conditions. In this paper, the operation of an SSPFC converter is briefly reviewed and the main principle behind the auxiliary circuit is explained. The new auxiliary circuit is introduced, its operation is explained, and its feasibility in a multilevel SSPFC is confirmed with experimental results.