Single‐stage high‐power factor half‐bridge flyback converter with synchronous rectifier

In this study, a single‐stage half‐bridge flyback converter using a synchronous rectifier (SR) is proposed to achieve unity power factor and higher efficiency. The proposed power factor correction can achieve almost a unity power factor and low input ripple current. The asymmetrical pulse‐width modulation (APWM) half‐bridge flyback converter operates under zero‐voltage switching to reduce switching losses. The conduction loss of the system can be reduced by replacing the diode rectifier with an SR using a low on‐resistance metal oxide semiconductor field effect transistor and the SR switch operates under zero‐current switching. Detailed analysis is presented on the proposed converter. Experimental results for a 24 V/200 W converter at a constant switching frequency of 100 kHz were obtained to prove the analysis.