A Single-phase AC-DC Converter Using Discontinuous Conduction Mode

Based on an existing three-phase AC-DC converter topology, a kind of step up/down single-phase AC-DC converter topology is proposed. It is characterized in that the power inductor is placed inside the bridge arm, the three power switches employ the same PWM driving signal and the converter is operated in discontinuous conduction mode, this control strategy can easily achieves unitary input power factor and step up/down output voltage. The operating principle of the single phase AC-DC converter is theoretically analyzed, including the limit of maximum duty cycle and the selection of key device parameters. The simulation verification is carried out by means of MATLAB/Simulink, results show that the single-phase AC-DC converter has simple circuit and easy to implement.