Comparison of input power factor correction techniques for buck converters in single-phase wireless power transfer systems

Active power factor correction (PFC) is standard for many ac-powered applications to decrease harmonic noise in the grid. PFC circuitry typically utilizes a boost converter, but a buck converter can also be used and has advantages of low output voltage and high efficiency over the universal input voltage range. Buck PFC converters have various implementations and exhibit high efficiency, good power factor, and acceptable harmonic distortion. This paper provides a review and comparison of buck PFC topologies, control techniques, and experimental performance. Discussion is provided on the most appropriate buck PFC topology for a 500-W wireless power transfer vehicle charging application.