H∞ control for a class of uncertain Delta operator-formulated systems with pole-assignment constraints and feedback gain variations

Based on linear matrix inequality (LMI), a design method of H
_infin
state feedback controller for a class of uncertain delta-operator formulated systems with pole-assignment constraints and feedback gain variations is introduced in this paper. The existing condition of the controller is translated into LMI form. The controller parameters can be obtained by solving the LMIs. When the controller parameters are excursive, the designed controller ensures the resulted closed-loop delta operator-formulated systems asymptotically stable and have the expected H
_infin
performance, also the poles of the resulted closed-loop systems are located in the assigned circular disk to satisfy the dynamic characteristics. A numerical example is given to illustrate the effectiveness of the design procedures.