2003 Volume 123 Issue 3 Pages 301-307
In most power electronic applications, the AC power input provided by the electric utility needs to be first converted to a DC voltage. Such conversion is usually accomplished by a diode rectifier due to its circuit simplicity and low cost. However, since diode rectifiers have some intrinsic problems such as low power factor and high harmonic distortion, a wide use of such rectifiers may cause noises, malfunction and heat damage in both electrical power systems and electrical machinery systems. This paper proposes a soft switched three-phase single switch boost-type rectifier. The proposed circuit can perform zero-voltage-switching (ZVS) without using any current and voltage sensors. For this circuit, both simulation and experiments have been performed. The results not only confirmed the zero-voltage-switching (ZVS) but also indicated that, compared to the conventional hard-switched rectifier, the proposed circuit can improve the efficiency as much as 1.7 to 4.7pt while keeping the same high power factor and small harmonic distortion in their AC input.