Dynamic output-feedback H∞ control for polytopic Delta operator systems

The problem of designing H_¿ dynamic output-feedback controllers for polytopic Delta operator systems is considered. Given a transfer function matrix of a system with polytopic uncertainty, an appropriate, not necessarily minimal, state-space model of the system is described which permits reconstruction of all its states. To this model, a new polynomial parameter-dependent approach to state-feedback H_¿ control is then used to design robust output-feedback controllers, which is different from conventional design framework. These controllers ensure the stability and guarantee a prescribed H_¿ performance level. A numerical example is employed to demonstrate the feasibility and advantage of the proposed design.