New smith predictor control using disturbance observer for steam superheater and steam pressure of the boiler

The steam superheater and the steam pressure systems are time delay systems that have poles near the origin in the left half plane or a pure integrator. Smith predictor can´t be applied to these systems any more, because of the steady state error for the step disturbance. In this paper, a new Smith predictor controller is proposed for the steam superheater and the steam pressure. A disturbance observer to estimate an input disturbance and a new controller to eliminate an effect of a disturbance are proposed. The simulation results verifies the efficiency of the proposed system.