A novel three-phase fly-back single-stage rectifier with single-pulse soft-switching

The technique of three-phase power factor correction in switch mode power supplies is still not mature and currently, most of the schemes are based on the combination of three single-phase power factor correction circuits with complex topology and control strategies resulting in high cost and low popularization. In this paper, a novel three-phase single-stage ac-dc converter system with single-pulse soft-switching (SPSS) is proposed. The principal characteristics are very simple topology, low complexity of control method, low mains current distortion and resistive fundamental behavior. In this converter, ZVS at turn off can be achieved by lossless snubber, and ZCS at the turn on can be obtained by operating under the DCM. The proposed converter can be satisfied the IEC standard sufficiently, and will provide an appropriate power supply scheme for telecommunication equipment such as mobile base stations. Computer simulation confirmed the validity of the circuit, showing sinusoidal and balanced input currents and a rippleless output voltage.