An improved auto-tuning scheme for PI controllers

✍ Scribed by Rajani K. Mudi; Chanchal Dey; Tsu-Tian Lee

• Publisher: Elsevier Science
• Year: 2008
• Tongue: English
• Weight: 982 KB
• Volume: 47
• Category: Article
• ISSN: 0019-0578
• DOI: 10.1016/j.isatra.2007.07.002

✦ Synopsis

Ziegler-Nichols tuned PI and PID controllers are usually found to provide poor performances for high-order and nonlinear systems. In this study, an improved auto-tuning scheme is presented for Ziegler-Nichols tuned PI controllers (ZNPICs). With a view to improving the transient response, the proportional and integral gains of the proposed controller are continuously modified based on the current process trend. The proposed controller is tested for a number of high-order linear and nonlinear dead-time processes under both set-point change and load disturbance. It exhibits significantly improved performance compared to ZNPIC, and Refined Ziegler-Nichols tuned PI controller (RZNPIC). Robustness of the proposed scheme is established by varying the controller parameters as well as the dead-time of the process under control.