Modeling of Single-Phase Three-Level Power Factor Correction Converter and Design of Double-Loop Controller

This paper presents the improved modeling of single-phase three-level power factor correction (PFC) converters and the design techniques of double-loop controllers. Conventional single-phase PFC circuits cannot easily be used to design double-loop controllers, due to the 120[Hz] ripple at the output voltage. A paper applying dq transform to a single-phase PFC circuit or research on controller design has been published, but research results on the double-loop controller design have not been clearly presented. The PFC converter having a three-level topology has the advantages of high efficiency and wide control range compared with conventional single-level PFC converters, but designing the double-loop controller is not easy due to the complexity of the control technique. In this paper, we present the research results of applying the single-phase PFC dual-loop controller design technique with 120[Hz] voltage ripple to a three-level topology. A state-space expression applicable to the full duty range was constructed to obtain a transfer function and a double-loop controller design was performed using MATLAB SISOTOOL. The designed controller demonstrated the validity of the design through PSIM simulation, and the designed controller is manufactured and experimented to verify the effectiveness of the system design.