Two-switch three-level discontinuous conduction mode boost rectifier design

Front-end converters for distributed power system (DPS) applications are extensively used in telecommunication systems to supply load converters and to charge batteries to provide backup energy during power grid blackouts. This paper explores the main features of the two-switch three-level boost rectifier operated in discontinuous conduction mode (DCM). The main contributions are reduced voltage stress and improved efficiency. Control strategies and design guidelines are provided in this paper. Because of the voltage stress reduction brought about by using a three-level topology, MOSFETs can be used to simultaneously increase the switching frequency and efficiency of the power factor correction (PFC) circuit. The discussion is supported by simulation results obtained from a 6.3kW prototype.