Eight-switch, three-phase rectifier for power factor correction

An eight-switch, three-phase neutral-point switch-clamped rectifier is presented in order to achieve a high input power factor and to draw sinusoidal currents from the AC mains. In the conventional three-phase, neutral-point switch-clamped rectifier, the circuit configuration consists of six power switches with voltage stress v/sub dc/ and three AC power switches with voltage stress v/sub dc//2. There are only four power switches with a voltage stress of the DC bus voltage and two AC power switches with a voltage stress of half the DC bus voltage in the proposed rectifier. The main functions of the proposed control scheme are to achieve unity input power factor, to draw sinusoidal line currents from the AC source, and to keep the DC link voltage constant. Analysis and a mathematical model of the proposed rectifier are derived. Some simulations and experimental results are provided in order to verify the effectiveness of the proposed control scheme.