A Design of Self-Tuning PID Controllers Based on a Pole-Assignment Scheme

Abstract

PID control schemes based on the classical control theory, have been widely used for real control systems up to now, since PID controllers have simple control structures, and are simple to maintain and tune. Furthermore, there are a lot of works with respect to tuning method of PID gains, since control performance depends on these gains. Also several self-tuning and auto-tuning techniques in the PID control systems have been reported for systems with unknown parameters. There, however, is not any result for discrete-time systems with unknown time-delays. On the other hand, the poleassignment control scheme has been reported as a useful self-tuning control technique for unknown time-delay systems. In this paper, a self-tuning PID control algorithm is proposed for unknown time-delay systems, based on the relationship between PID and pole-assignment controlschemes. The proposed scheme is numerically evaluated on an example of an ethylene cracking furnace temperature control.