Optimal preview control for linear time-variant discrete systems

This paper studies the optimal preview control problem of the linear variant-coefficient discrete-time system for the first time. The error system method in preview control theory of constant coefficient systems is modified and expanded using the property of difference operator. Consequently, we construct an augmented error system for the linear variant-coefficient discrete system and solve the problem how to construct the preview control model for the linear variant-coefficient discrete-time system. The optimal control input of augmented error system is obtained by using the result of the optimal control theory. The controller with preview feedforward compensation is obtained, when we transfer our conclusion into the controller of the original system. Finally, the results of numerical simulation are given to illustrate the proposed theorems.