ABSTRACT
The output tracking control problem is an important problem. Compared with the stabilization problem, tracking control is more difficult. This problem has attracted considerable experimental and theoretical attention due to the demands from practical dynamic processes in industry. The delta operator has the advantage of better numerical properties at high sampling rates and provides a theoretically unified formulation of continuous-time and discrete-time systems. The coefficient sensitivity approach is employed to investigate the problem of designing insensitive H∞ output tracking controllers for discrete-time systems with respect to controller coefficient variations based on delta operator models. The chapter presents a novel real bounded lemma for delta operator systems, which has potential for less conservative systems with uncertainties. Linear matrix inequality-based conditions are obtained for the existence of admissible controllers with respect to controller coefficient variations.
