One-cycle controller for parallel-connected interleaving critical continuous conduction mode PFC converter

This paper proposes a one-cycle controller for a critical conduction mode (CRM) power factor correction (PFC) converter, and with variable switching-frequency and variable sampling-frequency used to have three CRM PFC modules operating in paralleling and interleaving mode with a single digital signal processor (DSP). The one-cycle controller for the CRM PFC needs not detect the peak switching current and judge the zero-cross of the inductor current, so it can simplify control of the CRM PFC converter at a great extent. Experiments show that the controller provides very effective control of the current input and the voltage output, so it can achieve stable output voltage with high input power factor.