Design and Performance Analysis of a Non-Isolated DC-DC Converter With a Fractional-Order Output Filtering Capacitor

In this brief, a fractional-order modeling and controller design method is proposed, which considers the fractional-order characteristic of output filtering capacitors. The characteristics of an order-a output filtering capacitor are considered in the model of a DC-DC Buck converter, thus its effects on the open-loop performance of the converter are analyzed. Besides, the resonant frequency of the converter is deduced with considering the fractional-order output filtering capacitor. By using the open-loop fractional-order model of the converter, the controller is designed by the method of zero/pole placement. The validity and superiority of the proposed method is verified by simulation and experiment.