On the practical design of a single-stage single-switch isolated PFC regulator based on sliding mode control

In this paper, the variable-bandwidth hysteresis-modulation sliding-mode (VB-HM-SM) method is applied for a single-stage single-switch isolated power-factor-correction (PFC) regulator. In the regulator, the dc-dc stage works in CCM and is regulated by PWM, while the ac-dc boost stage works in DCM and is regulated by PFM. However, both PWM and PFM are realized by a sliding mode (SM) controller, and thus, unity power factor and fast output voltage regulation can be simultaneously achieved. Various aspects of the design, including the associated practical problems and the proposed solutions are detailed. A simple and easy-to-follow design procedure is also described. Simulation results are presented to illustrate the design procedure.