# Digital Self-tuning Control for Pressure Process

### Gediminas Liaucius, Vytautas Kaminskas

#### Abstract

Two digital control systems - Self-tuning PID (Proportional-Integral-Derivative) Control and Predictor-based self-tuning control with constraints - for the continuous-time pressure process control are presented in this paper. The digital self-tuning PID control with optimization of closed-loop parameters and sampling period is proposed. The multidimensional optimization problem of closed-loop parameters and sampling period is solved by subcomponent search method that enables dividing the problem to one-dimensional optimization problems. The golden section search is adjusted to solve those – one-dimensional - optimization problems. The predictor-based self-tuning control with constraints is adapted for both minimum-phase and nonminimum-phase process models. The control quality of pressure process of both control systems has been experimentally investigated. The results of experimental analysis demonstrate that the digital self-tuning PID control with optimization is more efficient as compared to predictive-based self-tuning control with constraints for pressure process.

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#### Paper Citation

#### in Harvard Style

Liaucius G. and Kaminskas V. (2014). **Digital Self-tuning Control for Pressure Process** . In *Proceedings of the 11th International Conference on Informatics in Control, Automation and Robotics - Volume 1: ICINCO,* ISBN 978-989-758-039-0, pages 612-619. DOI: 10.5220/0005012106120619

#### in Bibtex Style

@conference{icinco14,

author={Gediminas Liaucius and Vytautas Kaminskas},

title={Digital Self-tuning Control for Pressure Process},

booktitle={Proceedings of the 11th International Conference on Informatics in Control, Automation and Robotics - Volume 1: ICINCO,},

year={2014},

pages={612-619},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0005012106120619},

isbn={978-989-758-039-0},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the 11th International Conference on Informatics in Control, Automation and Robotics - Volume 1: ICINCO,

TI - Digital Self-tuning Control for Pressure Process

SN - 978-989-758-039-0

AU - Liaucius G.

AU - Kaminskas V.

PY - 2014

SP - 612

EP - 619

DO - 10.5220/0005012106120619