Fractional-Order PI/PD and PID Controllers in Power Electronics: The step-down converter case

In this manuscript, generalization for fractional-order PI/PD and PID approximations are synthesized and used to regulate output voltage of DC-DC step-down converter. A non-integer order proposal will be introduced by the fractional Laplacian operator, approximated by a bi-quadratic module within a bandwidth, exhibiting a flat phase curve exploited to enhance transient/permanent characteristics and system robustness. Non-integer order approach has been successfully merged with PI/PD and PID classic controllers and resulting structures showed feasibility and potential. Synthesized controllers are tested in a closed-loop control diagram to determine an effective, stable and fast regulation characteristic. In addition, electrical diagrams for controllers implementation are described. Numerical and experimental results are provided to corroborate proposal effectiveness.