A Six-Switch AC-AC Voltage Regulator with Totem-Pole PFC

This paper proposes a high-efficiency AC-AC voltage regulator with totem-pole power factor correction (PFC). Compared to conventional two-stage AC-AC converters, the proposed scheme achieves AC input to DC voltage and then to AC output conversion through a single-stage power conversion architecture, significantly reducing the number of power switching devices. Whereas conventional solutions typically require eight switching devices (four for the PFC stage and four for the inverter stage), this design utilizes the bidirectional switching characteristics of totem-pole PFC combined with high-frequency modulation strategies, accomplishing both high power factor correction and AC output regulation with only six switching devices. This approach eliminates intermediate redundant switching components. Experimental results demonstrate that the converter achieves unity power factor (PF > 0.99) and low input current harmonic distortion (THD < 5%) while maintaining a stable 220 VRMS AC output from a 90–276 VRMS AC input, with a 400 V DC bus voltage. The proposed topology exhibits higher system efficiency and lower hardware costs, making it suitable for applications such as renewable energy grid interfaces.