On-line identification of cascade control systems based on half limit cycle data

✍ Scribed by Utkal Mehta; Somanath Majhi

• Publisher: Elsevier Science
• Year: 2011
• Tongue: English
• Weight: 460 KB
• Volume: 50
• Category: Article
• ISSN: 0019-0578
• DOI: 10.1016/j.isatra.2011.01.011

✦ Synopsis

An on-line identification procedure is presented for cascade control systems in which both inner and outer loop process dynamics are modelled simultaneously by performing a single experiment. Departing from the conventional relay autotuning method where the controller is replaced by a relay, the proposed method is carried out on-line without breaking the closed-loop control. Exact analytical expressions are derived for process model parameters in terms of a few critical parameters of half period data of limit cycle output. Simulation examples are included to demonstrate the effectiveness of the proposed method.