Non-model control scheme for industrial processes with uncertain time delay

In this paper a new control scheme for uncertain time-delay systems is put forward, in which the precise model of the plant is not necessary. The time delay term is taken outside the characteristic equation of the closed-loop transfer function. Any variation of time delay does not influence the system´s dynamic performance and the steady state. And the change of the process parameters does not influence the stability of the system. The parameters of the controller, adopted as PI controller, do not need adjustment frequently so that it is easy to control the system in practice. Extensive simulations show that the proposed scheme is superior to the Smith predictor in the presence of large uncertainty in process dynamics.