Approaches to Closed-Loop Identification for Inferential Control

Abstract Five identification methods have been developed for application in closed loop, two of which utilize some special property of the inferential control scheme. All five have been computer tested and compared to the open-loop prediction-error least square approach. The two closed-loop least-square methods, though more complicated, did not yield any real improvement over the accuracy of the reference technique. The open-loop model-error least-square method improved accuracy but showed convergence problems. Finally, the two corrective methods proved far superior in accuracy, at the expense of slightly increased numerical complexity.