Abstract
Delayed autoregressive (DAR) model representation plays an important role in the design of a digital controller based on the partial model-matching and a model reference adaptive controller. Paying attentions to the decay of the AR coefficients in the model, we give a simplified algorithm for approximately solving the Riccati equation to calculate control gains. If the number of the AR coefficients increases from n to n+1, the computational results up to the order n can be retained and only the calculations associated with the additional (n+1) th term are needed; therefore the computational burden can remarkably be reduced. Utilizing the approximated solution, we present the simple structure of the digital PD controller and the digital I-PD controller, and discuss the accuracy of the proposed algorithm through numerical simulations.
