HIGH-BANDWIDTH CONTROL OF UNFOLDING-BASED AC-DC CONVERTERS

An apparatus includes an unfolder with three input terminals connected to a three-phase AC power source and three output terminals, p-terminal, o-terminal, and n-terminal, and a three-port converter connected to the unfolder and feeding a direct current (“DC”) load. The three-port converter includes input capacitors. A feedback control loop includes outputs of a p-terminal modulation index derived from a difference between p-terminal current and a p-terminal reference current and an n-terminal modulation index derived from a difference between n-terminal current and an n-terminal reference current. A feedforward control loop outputs an emulated p-terminal current and an emulated n-terminal current derived from differences between DC-link voltages and ideal DC-link voltages. A duty cycle controller is configured to generate duty cycles controlling switches of the three-port converter derived from the modulation indexes and the emulated currents.