Near-unity-power-factor single-phase AC-to-DC converter using a phase-controlled rectifier

The authors describe a near unity power factor single-phase AC-to-DC power converter based on the line frequency phase controlled rectifier with an input capacitor. The method of achieving near unity power factor AC-to-DC conversion is presented, and the advantages and disadvantages of this conversion techniques are described. The converter was first simulated on a computer and then measured in the laboratory. Converter harmonics were minimized, and the converter purity factor was maximised by careful design of the rectifier. The converter displacement power factor was maximised by the input capacitor. The converter performs near unity power factor AC-to-DC conversion for the minimum input voltage, maximum output current condition in which the DC load approaches the rating of the service supplying it