Digital control system applied to a PFC boost converter operating in mixed conduction mode

This paper proposes a digital control system applied to a power factor correction boost converter rated to a wide range of output power, operating in mixed conduction mode with fixed switching frequency. The control system is composed of an input current controller and an output voltage controller. The current controller comprises two predictive model-based control laws (one for the continuous conduction mode and another for the discontinuous conduction mode) and an operation mode selection algorithm, which is responsible for detecting the operation mode and selecting the appropriate control law. The output voltage is regulated using a proportional-integral voltage controller. Simulation and experimental results applying a low cost microcontroller are shown to ensure the operation of the proposed control system.