For a dual-rate control system where the output sampling interval is an integer multiple of the control interval, we propose a model-based inferential control scheme which uses a fast-rate model to estimate the intersample outputs and then supply them to a controller at the fast rate. Comparing such an inferential controller with the corresponding fast single-rate controller, we conclude that the former is no better in disturbance rejection capability; however, in the presence of model-plant mismatch, the former is advantageous in stability robustness of the closed-loop system. ? 2002 Published by Elsevier Science Ltd.
Dongguang Li, Sirish L. Shah, Tongwen Chen