Design of a single-stage a.c./d.c. converter for low power level applications

Abstract

The design of a single-stage a.c./d.c. converter operated in discontinuous conduction mode (DCM) for low power level applications is proposed. The proposed converter gives the good power factor correction, low line current harmonic distortions, and tight output voltage regulations. This converter also achieves a high efficiency by employing an active clamp method and synchronous rectifiers. The modelling and detailed analysis for the proposed converter are performed. To verify the performances of the proposed converter, a 90 W-converter has been designed. This prototype meets the IEC 61000-3-2 requirements satisfactorily with nearly unity power factor and high efficiency.