A process-model control for linear systems with delay

This paper is concerned with linear systems containing time delay in control. A process-model control which utilizes a mathematical model of the process in the minor feedback loop around the conventional controller to overcome delay is developed. A new process-model control system which can yield zero steady-state error and desired transient responses to step disturbances and arbitrary initial conditions is proposed. The remarkable feature of the proposed system is that the states of the model and the integrator are unobservable in the output of the model. It is shown that this structural property is the key by which the major problems of process-model control can be solved.