Neuro-Fuzzy System for Compensating Slow Disturbances in Adaptive Mold Level Control

[EN] Good slow disturbances attenuation in a mold level control with stopper rod is very important for avoiding several product defects and keeping down casting interruptions. The aim of this work is to improve the accuracy of the diagnosis and compensation of an adaptive mold level control method for slow disturbances related to changes of stopper rod. The advantages offered by the architecture, called Adaptive-Network-based Fuzzy Inference System, were used for training a previous model. This allowed learning based on the process data from a steel cast case study, representing all intensity levels of valve erosion and clogging. The developed model has high accuracy in its functional relationship between two compact input variables and the compensation coefficient of the valve gain variations. The future implementation of this proposal will consider a combined training of the model, which would be very convenient for maintaining good accuracy in the Fuzzy Inference System using new data from the process.This work is supported by a Project (AA-ELACERO, P211LH021-023) of the National Key Research and Development Program of Automatic, Robotic and Artificial Intelligence of Cuba.González-Yero, G.; Ramírez Leyva, R.; Ramírez Mendoza, M.; Albertos, P.; Crespo, A.; Reyes Alonso, JM. (2021). Neuro-Fuzzy System for Compensating Slow Disturbances in Adaptive Mold Level Control. Metals. 11(1):1-21. https://doi.org/10.3390/met1101005612111

Los softwares educativos como alternativa didáctica para la educación primaria desde la asignatura lengua española.

El artículo refleja los resultados obtenidos y el aporte práctico de la tesis de maestría presentada por la autora, la cual es portadora de la metodología para su implementación en la práctica y las formas de utilización de los softwares educativos como medios de enseñanza y herramientas de trabajo en la adquisición de conocimientos de la asignatura Lengua Española para la Educación Primaria. Los resultados expuestos aquí propiciarán el desarrollo de hábitos, habilidades, actitudes y capacidades, cumplimentada con la concepción didáctica desarrolladora la que le confiere al proceso docente educativo una nueva perspectiva a partir de su interactividad e independencia cognoscitiva

Un nuevo método de control PI no lineal robusto

This paper presents a robust nonlinear PI control. The dynamic balance of tradeoff between performance and robustness inside of a robustness region and to guarantee a balance's trayectory that minimize the integrated absolute error are the objectives of the design. A parabolic combined with static non linearity of dead zone and saturation is the nonlinear function used, its tuning has been formulated as a multi-objective optimization problem using global performance indices. With respect to other approaches of nonlinear PI control previously presented, the proposed tool is the first for solving the design's problem considered and is simple while increasing the performance-adjustment and the industrial applicability. A simulationt test for the complex process of mould level control in a steel continuous casting using the new robust nonlinear PI control illustrates the efficiency of this method.Este artículo presenta un método de control PI no lineal robusto. Los objetivos planteados para el diseño son: garantizar un balance dinámico de la relación de compromiso entre la robustez y el rendimiento dentro de una región de robustez y lograr que dicho balance se realice en la trayectoria que minimiza la integral del error absoluto. La función no lineal del error empleada es una parábola combinada con no linealidades estáticas de zona muerta y saturación, la cual es sintonizada mediante optimización multiobjetivo con índices de desempeño globales. Con respecto a propuestas anteriores de control PI no lineal, esta es la primera que resuelve el objetivo planteado logrando ser simple e incrementando su funcionalidad, ajuste y aplicabilidad industrial. La eficiencia del método es demostrada a escala de simulación, evaluando su desempeño para el proceso complejo de control de nivel de acero en molde de vaciado continuo

Modeling of Mould Level Control in a Continuous Casting for steel billets

[EN] This paper presents a model of system for the mould level control in a continuous casting machine for steel billets. The objective was to carry out the modeling of each element of the system including disturbances and transformations of the plant that affect the quality of control in the installation study object. It was obtained and validated an approximate model of the control system using physical laws governing the same one, experimental identification by special signals and parametric identification off- line. The model explicitly includes the phenomena of obstruction and erosion of the valve which have a significant impact on the operation of the plant. For hydraulic servo system achieved a gray box model contributes to a better understanding of the process and evaluates incidence of the multi-frequency implemented under conventional outline. Obtained the model can be studied scale simulation system operation and the effectiveness of advanced control solutions. The developed work is part of an I+D process that in the course of more than 10 years, it has contributed to that in the steelmaking where is carried out the investigation, there is a mould level control system that has positive impact on the quality of steel produced.[ES] Este trabajo presenta un modelo del sistema de control de nivel en molde de una máquina de vaciado continuo de palanquillas de acero. El objetivo fue realizar el modelado de cada elemento del sistema incluyendo las perturbaciones y transformaciones de la planta que más afectan la calidad del control. Se obtuvo y validó un modelo aproximado, utilizando leyes físicas, la identificación experimental mediante señales especiales e identificación paramétrica fuera de línea. En el modelo se incluyen de forma explícita los fenómenos de obstrucción y erosión en la válvula, que tienen una incidencia significativa en el funcionamiento de la planta. Para el servosistema hidráulico de la instalación se logró un modelo de caja gris que contribuye a un mejor entendimiento del comportamiento del proceso y a evaluar la incidencia de una implementación multifrecuencia bajo esquema convencional. Con el modelo obtenido es posible estudiar la operación del sistema a escala de simulación y la efectividad de soluciones de control avanzadas. El trabajo desarrollado es parte de un proceso de I+D que en el transcurso de más de 10 años ha contribuido a que en la acería donde se realiza la investigación, exista un sistema de control de nivel en molde que tiene impacto positivo sobre la calidad del acero producido.González Yero, G.; Ramírez Mendoza, M.; Rustán Téllez, BL. (2014). Modelado de Control de Nivel en Molde para Vaciado Continuo de Palanquillas de Acero. Revista Iberoamericana de Automática e Informática industrial. 11(1):44-53. https://doi.org/10.1016/j.riai.2013.11.003OJS4453111Alvarez, H., Lamanna, R., Vega, P., & Revollar, S. (2009). Metodología para la Obtención de Modelos Semifísicos de Base Fenomenológica Aplicada a una Sulfitadora de Jugo de Caña de Azúcar. Revista Iberoamericana de Automática e Informática Industrial RIAI, 6(3), 10-20. doi:10.1016/s1697-7912(09)70260-2ASSOCIATION, worldsteel, 2012. Steel Statistical Yearbook 2012. http://www.worldsteel.org/statistics/statistics-archive.html.Craig, I. K., Camisani-Calzolari, F. R., & Pistorius, P. C. (2001). A contemplative stance on the automation of continuous casting in steel processing. Control Engineering Practice, 9(9), 1013-1020. doi:10.1016/s0967-0661(01)00089-2Furtmueller, C., and L. D. Re, 2008. Control Issues in Continuous Casting of Steel. Proceedings of 17th IFAC World Congress. COEX, Korea, South.Furtmueller, C., L. D. Re, H. Bramerdorfer, and K. Moerwald, 2005. Periodic Disturbance Suppression in a Steel Plant with Unstable Internal Feedback and Delay. Proceedings of 5th International Conference on Technology and Automation. Thessaloniki, Greece.Jämsä-Jounela, S.-L. (2001). Current status and future trends in the automation of mineral and metal processing. Control Engineering Practice, 9(9), 1021-1035. doi:10.1016/s0967-0661(01)00073-9De Keyser, R. M. C. (1997). Improved mould-level control in a continuous steel casting line. Control Engineering Practice, 5(2), 231-237. doi:10.1016/s0967-0661(97)00230-xPaiuk, J., A. Zanini, M. Remorino, and O. Frola, 1989. The Automatic Mould Level Control for a Continuous Casting Process. Practical Implementation of Different Control Algorithms. Proceedings of 6th Symposium on Automatization in Mining, Mineral and Metal Proc. Buenos Aires, Argentina.Schuurmans, J., 2011. Continuous casting and mould level control. http://www.dcsc.tudelft.nl/∼wb2421/process.pdf.Thomas, B.G., Q. Yuan, S. Sivaramakrishnan, and a. S. P. Vanka, 2002. Transient Fluid Flow in a Continuous Steel-Slab Casting Mold. http://www.tms.org/pubs/journals/JOM/0201/Thomas/Thomas- 0201.html

Multi-agent system for steel manufacturing process

This work was carried out in the company ACINOX Las Tunas, Cuba, to design an integrated automation architecture based on intelligent agents for control, monitoring, and decision-making in the production process that guarantees an improvement in planning and management of the process in the steelwork plant. The great differences of technologies and systems of each steel mill and the multiple restrictions, methods, and techniques, within a wide dynamic strongly concatenated, do not generalize automation systems feasibly. In our research, we use international research results and the experience of the plant technologists to create three levels of distributed intelligent architecture: business, production planning-control, and steel manufacturing. Each level manages to integrate and balance the particular and general interests for efficient decision-making combined between hierarchy and heterarchy in this steelwork plant, which will be reflected in a reduction of at least 99% of the time used for decision-making concerning the current system, which can lead to a decrease in refractory costs, energy consumption, and production cost. The effectiveness of the solution is demonstrated with scenario validation and expert evaluation

Modeling and control of the hydraulic actuator in a ladle furnace

The dynamic behavior of the hydraulic actuator in a system for regulating the electrode's position is crucial for the operation of a Ladle Furnace. This work aims to identify, model, and control the hydraulic actuator in the Ladle Furnace of ACINOX Las Tunas. For identifying the system, input signals of Pseudo-Random Binary type and black box models were used. As a result, three models were obtained, two reflecting the process's asymmetric behavior according to the upward or downward movement. The third model approximates the process dynamic behavior around the operating point and includes the uncertainty caused by the weight variation during the electrode wear. The models obtained, with a fit greater than 85%, allow a better understanding of the study case behavior. In addition, these allowed the evaluation of the electrode's weight variation and tuning of several controllers. The optimal one was a novel non-linear PI controller of guaranteed robustness. In future works, the use of a non-linear function could be evaluated to compensate for the asymmetric behavior of the process