Remark 2: If Gs Gs m p and d 0 , conventional
Smith predictor plus PID control can eliminate time delay
effects and achieve good performance
Remark 3: Due to the complexity of process industries,
precise process model is only an ideal case. System
uncertainty may not be avoided in Smith predictor design.
The system uncertainty may lead to a deteriorating control
performance, such as oscillation and/or instability.
Remark 4: External disturbance is another challenging issue
in process control. Because the considered system has an
integrator constant external disturbance may lead to residual
error of system output.