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Parameter identification of a delayed infinite-dimensional heat-exchanger process based on relay feedback and root
Libor Pekař1,2, Mengjie Song3, Subhransu Padhee4
1Department of Automation and Control Engineering, Faculty of Applied Informatics, Tomas Bata University in Zlín, nám. T. G. Masaryka 5555, 760 01, Zlín, Czech Republic. pekar@utb.cz.
Scientific Reports
|June 6, 2022
Summary
This study analyzes a simple delayed model and applies it to identify parameters in complex heating-cooling systems using relay feedback. The method efficiently estimates multiple parameters from a single test, aiding process control.
Area of Science:
- Control Engineering
- Process Systems Engineering
- Applied Mathematics
Background:
- Industrial heating-cooling processes with heat exchangers are common but complex to model.
- Accurate parameter identification is crucial for effective process control.
- Existing identification methods may lack efficiency or accuracy for complex systems.
Purpose of the Study:
- To develop and validate a novel method for parameter identification of complex infinite-dimensional systems.
- To apply a simple delayed model for efficient parameter estimation in industrial heating-cooling processes.
- To compare the effectiveness of a saturated relay method with standard on/off tests and Autotune Variation Plus.
Main Methods:
- Analysis of pole loci for a simple delayed model with quasi-polynomial characteristic functions.
- Relay-based parameter identification using a saturated relay and dominant-pole-loci assignment.
- Numerical optimization techniques and Autotune Variation Plus for parameter refinement.
Main Results:
- The simple delayed model effectively represents high-order process dynamics.
- A single relay test using the saturated relay method allows for accurate estimation of multiple model parameters.
- The identified parameters provide satisfactory time and frequency domain responses for control tasks.
Conclusions:
- The proposed relay-based identification technique offers an efficient and accurate approach for complex industrial processes.
- The method successfully estimates multiple parameters from a single test, reducing computational effort.
- While effective for control, the identified parameters may not precisely represent physical quantities.
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