“On Tuning PI Controllers for Integrating Plus Time Delay Systems”Authors: David Di RuscioAffiliation: Telemark University College, P.O. Box 203, N-3901 Porsgrunn, Norway. Reference: 2010, Vol. 31, No. 4, pp. 145-164. |
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Keywords: PI controller, tuning, integrating system, time delay, maximum time delay error, frequency analysis
Abstract: Some analytical results concerning PI controller tuning based on integrator plus time delay models are worked out and presented. A method for obtaining PI controller parameters, Kp=alpha/(k*tau), and, Ti=beta*tau, which ensures a given prescribed maximum time delay error, dtau_max, to time delay, tau, ratio parameter delta=d\tau_max/tau, is presented. The corner stone in this method, is a method product parameter, c=alpha*beta. Analytical relations between the PI controller parameters, Ti, and, Kp, and the time delay error parameter, delta, is presented, and we propose the setting, beta=c/a*(delta+1), and, alpha=a/(delta+1), which gives, Ti=c/a*(delta+1)*tau, and Kp=a/((delta+1)*k*tau), where the parameter, a, is constant in the method product parameter, c=alpha*beta. It also turns out that the integral time, Ti, is linear in, delta, and the proportional gain, Kp, inversely proportional to, delta+1. For the original Ziegler Nichols (ZN) method this parameter is approximately, c=2.38, and the presented method may e.g., be used to obtain new modified ZN parameters with increased robustness margins, also documented in the paper.
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DOI: 10.4173/mic.2010.4.3
DOI forward links to this article:
[1] S. Alcántara R. Vilanova C. Pedret, (2013), doi:10.1016/j.jprocont.2013.01.003
[2] David Di Ruscio, (2012), doi:10.4173/mic.2012.2.1
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BibTeX:
@article{MIC-2010-4-3,
title={{On Tuning PI Controllers for Integrating Plus Time Delay Systems}},
author={David Di Ruscio},
journal={Modeling, Identification and Control},
volume={31},
number={4},
pages={145--164},
year={2010},
doi={10.4173/mic.2010.4.3},
publisher={Norwegian Society of Automatic Control}
};
