“Comparing PI Tuning Methods in a Real Benchmark Temperature Control System” Authors: Finn Haugen Affiliation: Telemark University College, Kjoelnes Ring 56, N-3918 Porsgrunn, Norway. Reference: 2010, Vol. 31, No. 3, pp. 79-91.

Keywords: PI tuning, air heater, Skogestad's method, Ziegler-Nichols' methods, Hägglund and Åström's method, Tyreus-Luyben's method, Relay method, Setpoint Overshoot method, Good Gain method.

Abstract: This paper demonstrates a number of PI controller tuning methods being used to tune a temperature controller for a real air heater. Indices expressing setpoint tracking and disturbance compensation and stability margin (robustness) are calculated. From these indices and a personal impression about how quick a method is to deliver the tuning result and how simple it is to use, a winning method is identified.

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DOI forward links to this article:
[1] David Di Ruscio, (2010), doi:10.4173/mic.2010.4.3
[2] S. Alcántara R. Vilanova C. Pedret, (2013), doi:10.1016/j.jprocont.2013.01.003
[3] F. Haugen, (2012), doi:10.4173/mic.2012.4.3


Comments from Sigurd Skogestad: I like the paper and the fact that the author is making such a comparison.

Haugen only considers the gain margin (GM) as a robustness measure. The phase margin (PM) is at a lower frequency and here the effect of using a smaller integral time (c=2, eqs.(15-17) in the paper) will have a much larger effect than for GM. If the author included PM (or maybe even better the delay margin), then I am quite sure that the robustness would get worse for the cases with small integral time (c=2) that give good disturbance rejection.

Some of the subjective measures are questionable. For example, SIMC gets 8 for Quickness, whereas the overshoot method gets 6. My own feeling, and also the experience from Statoil Mongstad, is that it is reverse.


References:
[1] Haugen, F., The Good Gain method for PI(D) controller tuning. TechTeach, 2010, http://techteach.no/publications/articles/good_gain_method/good_gain_method.pdf.
[2] Hägglund, T. and Åström, K.J., Revisiting the Ziegler-Nichols' Tuning Rules for PI Control. Asian J. Of Control, 2002. 4:364--380.
[3] Luyben, W. and Luyben, M. Essentials of Process Control. McGraw-Hill, New York, 1997.
[4] O'Dwyer, A. Handbook of Controller Tuning Rules. Imperial College Press, London, 2003.
[5] Seborg, D., Edgar, T., and Mellichamp, D., Handbook of Controller Tuning Rules. Process Dynamics and Control, 2004.
[6] Shamsuzzoha, M., Skogestad, S., and Halvorsen, I., On-Line PI Controller Tuning Using Closed-Loop Setpoint Response. In Proc. IFAC Conf. on dynamics and control of process systems processes (DYCOPS), Belgium, July. 2010.
[7] Skogestad, S., Simple analytic rules for model reduction and PID controller tuning. Journal of Process Control, 2003. 13(4):291--309. doi:10.1016/S0959-1524(02)00062-8.
[8] Skogestad, S., Simple analytic rules for model reduction and PID controller tuning. Modeling, Identification and Control, 2004. 2(2):85--120. doi:10.4173/mic.2004.2.2.
[9] Ziegler, J. and Nichols, N., Optimum settings for automatic controllers. Trans. ASME, 1942. 64:759--768.
[10] Åström, K.J. and Hägglund, T., PID Controllers: Theory, Design and Tuning. ISA, 1995.


BibTeX:
@article{MIC-2010-3-1,
  title={{Comparing PI Tuning Methods in a Real Benchmark Temperature Control System}},
  author={Finn Haugen},
  journal={Modeling, Identification and Control},
  volume={31},
  number={3},
  pages={79--91},
  year={2010},
  doi={10.4173/mic.2010.3.1},
  publisher={Norwegian Society of Automatic Control}
};