Study and implementation of a single-stage three-phase AC-DC converter

The paper presents a single-stage three-phase AC-DC converter, which integrates a three-phase AC-DC boost converter with a high step-up DC-DC converter by using single switch. The front semi-stage of the proposed converter is operated in discontinuous conduction mode for power factor correction and the rear semi-stage is operated in continuous conduction mode. The output-capacitor stack and the coupled inductor are utilized to achieve high voltage gain. The voltage stress on the switch is less than the output voltage. The low rating-voltage and conduction-resistance MOSFET can be selected to reduce the conduction losses. The leakage-inductor energy of the coupled inductor is recycled for increasing the conversion efficiency. Furthermore, the operating principle and steady-state analysis are described. Finally, a prototype hardware circuit is implemented to illustrate the performance of the proposed converter.