抄録
Recently, a large number of design methods for model reference adaptive control system (MRACS) have been proposed by the researchers of stability theorem. Among them, Monopoli proposed an attractive design method for MRACS by introducing an augmented error signals and signals obtained from filters operating on the plant's input and output signals. But the MRACS with an augmented error signal has a complicated construction and algorithms due to introduction of an augmented error signal and new signals, and the filter's parameters could not be precisely determined. Furthermore, the above adaptive algorithms require the information on one plant parameter.
In this paper, a design method for discrete MRACS is proposed based on Lyapunov's direct method. It is shown that the proposed MRACS is simply constructed by the use of only adjustable elements in the feedback and feed-forward paths of a plant. For the adaptive algorithms proposed here, no information on an unknown plant parameter is required. Furthermore, the relationship between the proposed MRACS and the MRACS with an augmented error signal is discussed. Finally, the validity of the proposed adaptive algorithms is demonstrated by numerical examples.
