Model Predictive Control Strategy for Single-Phase Four-Cell Flying-Capacitor Totem-Pole PFC Converter with Integrated Power Pulsation Buffer

This paper proposes an integrated power pulsation buffering (PPB) technique for a bidirectional single-phase fourcell flying capacitor multilevel (TP-4CFC) totem-pole power factor correction (PFC) converter. By leveraging the inherent energy storage of the flying capacitors, the architecture downsizes the required electrolytic DC-link capacitance and eliminates the need for separate decoupling circuits, enhancing system reliability and power density. A multi-objective model predictive current control (MOMPCC) strategy is employed to simultaneously regulate the grid current and flying capacitor voltages, effectively enabling partial PPB. A bang-bang-type voltage reference scheme based on instantaneous power deviation is used for capacitor voltage regulation. The proposed controller utilizes only lowfrequency inductor current and redundant switching states for PPB operation, simplifying hardware requirements. Simulation results demonstrate a significant reduction in DC-link voltage ripple by 53% and a Total Harmonic Distortion (THD) of 2.85% under integrated PPB operation, with a maximum switching frequency limited to 100 kHz. The presented solution is highly suitable for compact and long-lifetime applications such as EV onboard chargers and server power supplies.