抄録
In this paper, systems with bounded disturbances and unknown relative degree not exceeding three are considered, and we propose a design method of model reference adaptive control systems.
The objective considered here is to design the control system so that the norm of the output error, between the output of a controlled object and that of a reference model, converges to any small region in the neighborhood of the origin. In order to achieve the objective, the unknown parameters and the unknown bounded disturbance are estimated by using the σ modification method, and the control system is constructed by using the estimated parameters. In this control system, we derive the relation between the output error and the design parameters. From this relation, it will be shown that the upper bound of the norm of the ultimate output error can be reduced to any small value by increasing the value of only one design parameter. Moreover, if the prior information about the upper bound of the norm of the unknown parameters is known, it will be shown that, when no disturbance is present, we can construct the control system by using the prior information in which the convergence of the output error to zero is guaranteed.
Finally, computer simulation results are presented to illustrate the effectiveness of the proposed method.
