Hysteresis-Based Control of a Single-Phase Multilevel Flying Capacitor Active Rectifier

The deployment of a single-phase, multilevel flying capacitor converter as a 1.5-kW active rectifier is discussed in this paper. The challenges associated with this approach include providing unity power factor, regulating the dc output voltage, and maintaining balanced voltages across the flying capacitors. In such applications, the input current is usually controlled via a reference-frame-based control approach. Here, a different approach, which is based on the hysteresis current-mode control scheme, is applied. The simulation and experimental results for both reference-frame-based and hysteresis-based controllers are presented and compared. The results show that the hysteresis-based method exhibits a tighter regulation of the input current and offers easier hardware implementation.