Flyback-Based Single-Stage Power-Factor-Correction Scheme With Time-Multiplexing Control

A flyback-based single-stage power-factor-correction scheme with time-multiplexing control (TMC) is proposed. As a portion of the input power will be transferred to the output after the first power processing to improve the conversion efficiency, the output voltage would contain substantial low-frequency ripple. An isolated auxiliary circuit based on forward topology is therefore added to the converter to serve as a buffer and a ripple suppression circuit. With TMC, all the power processes can be achieved by a single transformer to lower the size and cost of the converter. In addition, the proposed converter inherits bulk capacitor (auxiliary) voltage clamping capability. The experimental results confirmed the effectiveness of the proposed scheme with high power factor, natural bulk capacitor (auxiliary) clamping voltage, and tight output regulation.