DISTURBANCES ESTIMATION FOR MOLD LEVEL CONTROL IN THE CONTINUOUS CASTING PROCESS

Karim Jabri, Bertrand Bele, Alain Mouchette, Emmanuel Godoy, Didier Dimur

Abstract

This paper addresses the problem of mold level fluctuations in the continuous casting process, which strongly penalize the quality of the final product and lead to a costly machine downtime. Therefore, the mold level is controlled using a stopper as the flow control actuator and a level sensor. Under normal casting conditions, the current controllers provide suitable performances but abnormal conditions require manual intervention, such as the decrease of the casting speed, in particular when undesired disturbances like clogging/unclogging or bulging occur. These disturbances increase in severity for certain steel grades or at high casting speeds. Therefore, this paper focuses on the on-line disturbances estimation in order to introduce compensation actions. Starting with the presentation of the continuous casting process, the description of the model of the machine, and highlighting the main control challenges, an observer estimating clogging and bulging disturbances is then developed. This design may help future control architectures based on disturbances estimation. The proposed observer is finally validated by extracting disturbances from experimental signals measured on a continuous casting plant.

References

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Paper Citation


in Harvard Style

Jabri K., Bele B., Mouchette A., Godoy E. and Dimur D. (2008). DISTURBANCES ESTIMATION FOR MOLD LEVEL CONTROL IN THE CONTINUOUS CASTING PROCESS . In Proceedings of the Fifth International Conference on Informatics in Control, Automation and Robotics - Volume 3: ICINCO, ISBN 978-989-8111-32-6, pages 119-124. DOI: 10.5220/0001486601190124


in Bibtex Style

@conference{icinco08,
author={Karim Jabri and Bertrand Bele and Alain Mouchette and Emmanuel Godoy and Didier Dimur},
title={DISTURBANCES ESTIMATION FOR MOLD LEVEL CONTROL IN THE CONTINUOUS CASTING PROCESS},
booktitle={Proceedings of the Fifth International Conference on Informatics in Control, Automation and Robotics - Volume 3: ICINCO,},
year={2008},
pages={119-124},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0001486601190124},
isbn={978-989-8111-32-6},
}


in EndNote Style

TY - CONF
JO - Proceedings of the Fifth International Conference on Informatics in Control, Automation and Robotics - Volume 3: ICINCO,
TI - DISTURBANCES ESTIMATION FOR MOLD LEVEL CONTROL IN THE CONTINUOUS CASTING PROCESS
SN - 978-989-8111-32-6
AU - Jabri K.
AU - Bele B.
AU - Mouchette A.
AU - Godoy E.
AU - Dimur D.
PY - 2008
SP - 119
EP - 124
DO - 10.5220/0001486601190124