Control of a flyback converter in power factor correction mode: compromize between the current constraints and the transformer volume

The aim of this paper is to present a new method to control the flyback converter in PFC mode. This control combines two conduction modes: discontinuous and continuous (mixed control). It allows to decrease the semiconductor current constraints and gives a good compromize between these constraints and the transformer volume. Both discontinuous and mixed conduction modes are analyzed and simulated. The simulation results are validated thanks to a workbench made for each conduction mode. To show the advantages of the new control, comparison between the traditional method (discontinuous conduction) and the mixed control results is also given.