Analysis and design considerations of a unity power factor quasi-resonant rectifier

Existing AC-DC low harmonic rectifiers are costly and require complex control schemes to minimize input current distortion. Introduced here is a new class of low cost AC-DC high power factor/low harmonic rectifiers. With active zero current resonant switch (ZCS) added to the diode bridge rectifier, the converter is capable of drawing a high quality input current waveform naturally at nearly unity power factor, without switching losses and current line transducers. Thus, a simple single phase or 3 phase AC-DC high power factor rectifier is obtained. Full theoretical analysis is effectuated. Simulation and experimental results are supplied to demonstrate the validity of the concept