A modified Sheppard-Taylor power factor corrector operating in Discontinuous Capacitor Voltage Mode

This paper presents a new study of a modified Sheppard-Taylor-based Power Factor Correction (PFC) circuit used for single-phase low-voltage high-current applications. The proposed converter is designed to operate in Continuous Inductor Current Mode and Discontinuous Capacitor Voltage Mode (CICM/DCVM). In this mode of operation, the PFC provides zero-voltage turn-off switching, as well as natural input power factor correction over a wide range of input voltage. Due to the simplified control circuit and reduced switch current stress that it yields, this mode of operation offers better efficiency and higher reliability than the CICM/CCVM previously reported in the literature. The theoretical analysis of the proposed PFC is presented and verified through digital simulations. It is shown that this rectifier exhibits high input power factor and low line current distortion at low output voltage level.