A single-stage single-switch AC/DC converter using magnetic switch

This paper presents a new single-stage single-switch converter, which is based on the combination of a boost PFC converter and a forward DC/DC converter. The AC/DC converter uses an auxiliary winding coupled to the transformer, for shaping the input current. The Auxiliary winding is placed between the DC bus capacitor and the input rectifier, and actually plays the role of a magnetic switch to drive the input inductor. Using magnetic switch leads to lower cost and higher efficiency. Output regulator is a forward converter, which is operating in discontinuous conduction mode. Thus, in comparison to a flyback converter, the size of the transformer is reduced, and the output inductor is also removed. Basic operating principles of the proposed converter are discussed and the simulation results are presented. A prototype of the proposed converter is implemented to verify the theoretical analysis.