A ZVS/ZCS three-level three-phase high-power-factor rectifier

A novel single-stage three phase high power factor converter based on three-level zero-voltage and zero-current soft-switching circuit is proposed, which can mitigate a contradiction between voltage rating of power switches and high-power factor in the conventional three-phase single-switch DCM boost power-factor correction circuit and provides softs-witch for all power switches. The three-level structure reduces the voltage stress across the power switches to 50% of the bus voltage. For the same condition of input voltage and power switch voltage rating, the proposed converter presents lower harmonic distortion of input current than the conventional three-phase single-switch DCM boost rectifier. The operation principle of the converter circuit and the high-power-factor condition are analyzed. Also, the transfer gain K and computation formula of input boost inductors are deduced. Finally, simulation and experimental results are given in this paper.