State-Disturbance Composite Observer for Bilinear Systems

Like linear systems, the state and disturbance observers for bilinear systems must be considered in order to realize the state feedback and/or disturbance feedforward control in the case where some of the states and/or disturbances are unmeasurable. This paper addresses the design issue of minimal order state observers for bilinear systems; then discusses a new method of designing minimal order state-disturbance composite observers. Finally, the application of this state-disturbance composite observer to the headbox control system in papermaking process is presented as example. The simulation results and on-line performance evaluation show that this composite observer is effective.