Design of sliding-mode controller for discrete singular perturbation systems

A two-stage sliding-mode controller design for the discrete singular perturbation system is investigated in this paper. At first, we design the slow and fast sliding-mode controllers for the subsystems individually. Then we obtain the composite sliding-mode controller via the subcontrollers. The Lyapunov stability test for the reaching mode of the subsystems and full-order system are examined. The stability bound problem of the singular perturbation parameter in such a control system is also discussed. An efficient way of eliminating the chattering problem is developed. A steam power system is given to demonstrate the proposed schemes