Analysis and design of a three-phase buck-boost quasi-resonant reduced switch rectifier

A simple, low-cost, reduced-switch, three-phase ac-dc quasi-resonant buck-boost converter is proposed in this paper. The converter can operate with an excellent input power factor correction and is suitable for applications where a converter needs to produce a wide range of output dc voltages and power levels. In the paper, the converter operation is explained and mathematical analysis is performed to determine its steady-state characteristics. A design procedure for the selection of key components is developed based on the results of the analysis and is then demonstrated with an example. The feasibility of the converter is confirmed with experimental results obtained from a prototype converter.