Re-design of Smith predictor systems for performance enhancement

In this paper, a new design for Smith Predictor systems is presented. It employs a deliberately mismatched model to enhance performance over a perfectly matched system while using a simple primary controller. The design methodology is formulated in the frequency domain as an optimization problem and it turns out that an approximate solution can be obtained using the linear least squares method. To improve the performance further, a modified Smith Predictor system structure is also proposed, and it reduces the system into one involving second-order dynamics for the primary controller design. Illustrative simulation of several typical processes are included.