A time delay compensation strategy for uncertain single-input single-output nonlinear processes

The dynamic behavior of many processes is characterized by time delays due to transportation lags and measurement delays, which put severe limitations on the performance of control systems. In this paper, a new time delay com pensation strategy for single-input single-output nonlinear processes subje ct to modeling uncertainty is proposed. At first, controller design based o n input-output feedback linearization for a class of nonlinear systems with an input time delay is presented. Then, the input-output linearization con troller is used in an internal model control (IMC) structure with time dela y compensation. Finally, IMC with feedback compensation is proposed to redu ce the effect of modeling errors on the performance and robustness. An adju stable parameter in the feedback compensation can be tuned to satisfy a par ticular specification. The effectiveness of the proposed method is illustra ted via simulation on the temperature and concentration control of a noniso thermal chemical reactor with an input delay.