Robust fixed-order dynamic output feedback controller design for fractional-order systems

This study deals with designing a robust fixed-order dynamic output feedback controller for uncertain fractional-order linear time-invariant systems by means of linear matrix inequalities (LMIs). The authors' purpose is to design a low-order controller that stabilises the fractional-order linear system in the presence of model uncertainties. No limiting constraint on the state space matrices of the uncertain system is assumed in the design procedure. Furthermore, adopting the most complete model of linear controller, with direct feedthrough parameter, does not disturb the LMI-based approach of developing robust stabilising control. Eventually, the authors illustrate the advantages of the proposed method by some examples and their numerical simulation.