In this paper, a new approach for fixed-order H-infinity and H-2 dynamic output-feedback controller design of continuous-time systems with state space polytopic uncertainty is proposed. This approach is based on the use of some instrumental matrices, which operate as a tool to decouple the controller parameters and the Lyapunov matrices. The stability of the closed-loop system as well as H-infinity and H-2 performance criteria are expressed by a set of linear matrix inequalities based upon linearly parameter-dependent Lyapunov matrices. Iterative procedure for updating the instrumental matrices using the previous controller can increase the performance of the approach. Simulation results demonstrate the effectiveness of the proposed method.
Colin Neil Jones, Bratislav Svetozarevic, Wenjie Xu
Maryam Kamgarpour, Luca Furieri