Abstract

Conventional single phase AC/DC converters use a two stage power configuration to provide a regulated DC power supply at high input power factor. Elimination of one of these stages can reduce the cost, weight, size, complexity and increase the overall reliability of this converter. This thesis proposes a single stage power factor correction converter circuit. This proposed converter circuit uses the traditional non-power-factor corrected circuit configuration with only few additional components. These are: an additional winding on the high frequency transformer, a small high frequency inductor and three diodes. The topology allows the output voltage regulation and input current shaping with a single power processing stage and one control chip. In addition, it is shown that this converter can be designed to offer soft switching of the full bridge switches. The operating principles of the proposed converter are discussed and its performance characteristics under steady state conditions are examined. A design procedure is illustrated to select the components of the converter for a 500 W power supply operating at 50 kHz. Theoretical results are verified with simulation and experimental tests on a 500 W laboratory prototype.