Discrete Time Multivariable Adaptive Control for Non-Minimum Phase Plants with Unknown Dead Time

Abstract

A new method for designing a discrete time multivariable adaptive control system is presented. The controlled plant is a multi-input, multi-output stable, non-minimum phase plant with unknown dead time. In the proposed method an adaptive control is carried out using a controller designed by a certain decomposed representation of the unknown plant. This method requires no a priori knowledge regarding the dead time of the plant and the plant structure, and may in many cases require less computation than other methods which have been proposed for non-minimum phase systems. The stability of the proposed adaptive control system is considered. Moreover, the relation between the proposed method and the conventional model reference adaptive control or adaptive pole placement method is clarified. Finally, the results of computer simulation of adaptive control, applied to minimum phase plant without dead time and non-minimum phase plant with dead time, are included to illustrate the effectiveness of the proposed method.