Input Current Waveform Improvement of a Single-Phase Switching Power Supply with Single Switching Device

Abstract

The development of fast and low cost switching devices resulted in large use of high frequency power sources also in small equipments for home use. The capacitor input type rectifier is widely used in such equipments owning to simple configuration and high efficiency, but the effect of the harmonics present in its input current to the power system is becoming not negligible. Therefore, rectifiers with sinusoidal input current is strongly desired. The authors proposed a new rectifier topology named dither rectifier, which achieves over 99% power factor with few modifications to conventional circuits, in both power circuitry and controller. In this paper, the various configurations and control methods that can be used in the dither rectifier are presented. Three experimental circuits are also presented, using different configurations.