Abstract
There are lots of researches on designing self-tuning control(STC) systems for linear nonminimum-phase systems. A wide variety of existing methods on designing STC systems are conceptually classified into the following two groups. The one is based on minimization of an error criterion, and the other is on pole-assignment of the closed-loop system. On the other hand, in order to guarantee the tracking property for the reference signals, the internal model which corresponds to the reference signals, has to be inserted into the control system based on the internal model principle. However, the variance of the control error signal may become large by inserting the internal model, because the stochastic noise may be amplified. In this paper, a design method of self-tuning pole-assignment control systems with internal models is proposed based on minimizing the linear quadratic cost function. The newly proposed control scheme has the feature that the variance of the stochastic noise in the control system is reduced owing to the minimum variance control scheme, and also the tracking property to the reference signal is assured owing to the internal model. The proposed control scheme is numerically evaluated on some simulation examples.
