Discrete-Time Q-Dissipative Control with Application to Stability Margin Guarantee

This paper studies discrete-time dissipative control and proposes a design method for a controller ensuring a given stability margin. The paper begins by generalizing an existing continuous-time dissipative control method into the discrete-time case, with emphasis on a quadratic dissipativity, measured by Q, of the loop transfer system that is not necessarily stable. Then, by taking suitable Q, the feedback system is designed so that it is robustly stable against a pre-specified range of perturbations inserted in the feedback loop. This robustness includes the classical gain and phase margins as a special case.