Relay-tuned FSA control for unstable processes with deadtime

Author

Wang, Q.-G. ; Lee, T.H. ; Tan, K.K.

Author_Institution

Dept. of Electr. Eng., Nat. Univ. of Singapore, Singapore

Volume

1

fYear

1995

fDate

21-23 Jun 1995

Firstpage

311

Abstract

In this paper, the control of open-loop unstable processes with deadtime is considered. Astrom and Hagglund´s (1984, 1988) relay auto-tuning for PID regulators is extended to such processes. Some conditions for limit cycles under relay feedback are given. A first-order unstable rational function plus deadtime is employed to model a class of the processes with a single unstable pole and deadtime. Its parameters are extracted from a relay feedback experiment. The modified finite spectrum assignment is used to control such a process and a simple method is then developed to obtain the closed-form control law for ease of real-time implementation. It is also shown that so auto-tuned MFSA system is practically stable in the face of perturbations in process dynamics. Simulation examples are included for illustration

Keywords

adaptive control; delays; feedback; limit cycles; poles and zeros; relay control; self-adjusting systems; stability; three-term control; PID regulators; closed-form control law; deadtime; limit cycles; modified finite spectrum assignment; open-loop unstable processes; relay auto-tuning; relay feedback; relay-tuned FSA control; unstable processes; Automatic control; Feedback; Limit-cycles; Manufacturing processes; Open loop systems; Polynomials; Process control; Pulp manufacturing; Regulators; Relays;

fLanguage

English

Publisher

ieee

Conference_Titel

American Control Conference, Proceedings of the 1995

Conference_Location

Seattle, WA

Print_ISBN

0-7803-2445-5

Type

conf

DOI

10.1109/ACC.1995.529259

Filename

529259