Simplified Control Technique for High-Power-Factor Flyback Cuk and Sepic Rectifiers Operating in CCM

Control techniques for high-power-factor rectifiers which do not need input voltage sensing are gaining considerable attention due to their simpler implementation and inherently superior stability, as compared to conventional average or peak current mode control. Among these, the solutions based on the integration of a current signal (switch, diode, or inductor current) provide an inherent noise immunity, which makes them further appealing. This paper proposes a simple implementation of one such control technique for high-power-factor flyback, Cuk, or Sepic rectifiers, which, while still retaining a high power factor, further reduces the control complexity, thus making the solution very attractive for smart-power integration. A 200-W flyback rectifier with the proposed control technique was implemented and tested. The achieved results are in good agreement with the expected performance.