Self-Tuning Digital PIR Controller Design and Application

A methodology for tuning the digital proportional-integral-retarded (PIR) controllers via the dominant pole placement approach is presented in this paper. Based on the desired performance criteria for the closed-loop system, the dominant poles are positioned, while the remaining poles are allocated to specific locations, ensuring they are sufficiently distant from the dominant poles. To achieve this, a desired polynomial is formulated, and the coefficient equalization method is applied. The presented approach is illustrated through an industrial application employing Kalman Filter (KF) based online system identification. The results show that both the PIR controller itself and the online system identification-based tuning methods exhibit satisfactory performance across various load characteristics, thereby affirming their validity and effectiveness for utilization in industrial control systems with delays.