LMI-based robust stability and stabilization analysis of fractional-order interval systems with time-varying delay

This paper investigates the robust stability and stabilization analysis of interval fractional-order systems with time-varying delay. The stability problem of such systems is solved first, and then using the proposed results a stabilization theorem is also included, where sufficient conditions are obtained for designing a stabilizing controller with a predetermined order, which can be chosen to be as low as possible. Utilizing efficient lemmas, the stability and stabilization theorems are proposed in the form of LMIs, which is more suitable to check due to various existing efficient convex optimization parsers and solvers. Finally, two numerical examples have shown the effectiveness of our results.Comment: arXiv admin note: text overlap with arXiv:1807.1082

A novel LMI-based Method for Robust Stabilization of Fractional-order Interval Systems with 1≤α<21\le\alpha<2

This paper deals with the problem of robust dynamic output feedback stabilization of interval fractional-order linear time invariant (FO-LTI) systems with the fractional order $1\le\alpha<2$. In this study, a new formulation based on the null-space analysis of the system matrices is proposed using linear matrix inequalities (LMIs). The applied uncertain model is the most complete model of linear interval systems, in which all of the systems matrices are interval matrices. A robust dynamic output feedback controller is designed that asymptotically stabilizes the interval FO-LTI system, where no limiting constraint is assumed on the state space matrices of the uncertain system. Eventually, a numerical example with simulations is presented to demonstrate the effectiveness and correctness of the theoretical results.Comment: arXiv admin note: substantial text overlap with arXiv:1807.10827, arXiv:1701.0534

Robust Stabilization of Fractional-order Interval Systems via Dynamic Output Feedback: An LMI Approach

This paper addresses the problem of robust dynamic output stabilization of FO-LTI interval systems with the fractional order 0<{\alpha}<2, in terms of linear matrix inequalities (LMIs). Our purpose is to design a robust dynamic output feedback controller that asymptotically stabilizes interval fractional-order linear time-invariant (FO-LTI) systems. Sufficient conditions are obtained for designing a stabilizing controller with a predetermined order, which can be chosen to be as low as possible. The LMI-based procedures of designing robust stabilizing controllers are preserved in spite of the complexity of assuming the most complete model of linear controller, with direct feedthrough parameter. Finally, some numerical examples with simulations are presented to demonstrate the effectiveness and correctness of the theoretical results. Keywords: Fractional-order system, interval uncertainty, linear matrix inequality (LMI), robust stabilization, dynamic output feedback.Comment: arXiv admin note: substantial text overlap with arXiv:1701.0534