Design of a power-factor-correction converter based on half-bridge topology

A single-stage ac/dc converter based on a half-bridge topology suitable for low-power-level applications is proposed. The proposed converter has high power factor, low harmonic distortion, and tight output regulations. An asymmetrical control and synchronous rectification are employed to reduce the switching and rectification losses, respectively. The modeling and detailed analysis are performed to derive the design equations. Based on these design equations, a prototype converter has been designed and tested by experiment. This prototype meets the IEC 61000-3-2 regulations with near-unity power factor and high efficiency.