Fractional-order differentiation offers new degrees of freedom that simplify the design of high-performance dynamic controllers. The CRONE control system design (CSD) methodology proposes the design of robust controllers by using fractional-order operators. A software toolbox has been developed based on this methodology and is freely available for the international scientific and industrial com...

A method is proposed for automatic synthesis of quantitative feedback theory (QFT) based robust fractional-order controllers. The problem of QFT controller synthesis is formulated as an interval constraint satisfaction problem, where the nonlinear and non-convex robust stability and tracking bound specifications form the constraints. The problem is solved using the branch and prune algorithm. A...

This paper deals with the design of nonlinear PI control techniques for regulating a class of fractional-order dynamics governed by a commensurate-order model, possibly nonlinear, perturbed by an external disturbance. The suggested control algorithm is the combination between a fractional-order PI controller and a nonlinear robust version of it, namely a secondorder sliding mode control algorit...