Fixed-frequency zero-voltage switched low-cost single phase high quality rectifier circuits with minimum voltage stress across the switches

This paper presents a family of circuits for single-phase diode rectifiers capable of drawing approximately sinusoidal current waveforms at unity power factor with high efficiency and minimum voltage stress across the switches. Moreover, they are suitable to work as boost and flyback power converters. These topologies use coupled inductors with capacitors for resonance to achieve zero voltage switching (ZVS) of the converters. The circuits consist of a single-phase diode bridge rectifier, followed by a boost stage containing two switches-the main switch for controlling the output DC voltage and the auxiliary switch for achieving ZVS. The output voltage is regulated by employing fixed frequency control. The paper explains the principle of operation and describes the analysis of each mode of operation for both boost and flyback converters. It also gives design criteria, derived from the mathematical analysis carried out, for achieving ZVS under all loading conditions from no load to full load. The simulation results obtained using PSPICE demonstrate the validity of the proposed power converters