M. A. Barrón¹ & J. González²

¹ Departamento de Materiales, Universidad Autónoma Metropolitana-Azcapotzalco Apartado Postal 75-338, México, D.F., México.

² Departamento de Sistemas Universidad Autónoma Metropolitana-Azcapotzalco Apartado Postal 75-338, México, D.F., México.

Received: July 3^th 2002.
Accepted May 9^th 2003.

Abstract

A nonlinear mathematical model of a vacuum-based continuous casting process and an implicit nonlinear controller are developed. The aim of the controller is the regulation of the mold and tundish molten steel levels. In the proposed approach, the output error is designed to be asymptotically stable, and the current values of the control inputs are numerically determined using the Newton-Rapson iterative procedure. The dynamic performance of the closed-loop system is analyzed using computer simulations.

Keywords: Discrete controller, Implicit control, Level control.

Resumen

En este trabajo se desarrollan un modelo matemático de un proceso de colada continua de acero mediante vacío y un controlador implícito no lineal. El objetivo del controlador es regular los niveles de acero fundido en el molde y el distribuidor. En el enfoque propuesto, el error de salida se diseña de modo que el sistema a lazo cerrado sea asintóticamente estable y los valores actuales de las entradas de control se determinan mediante el método iterativo de Newton-Raphson. El desempeño dinámico del controlador se analiza mediante simulaciones numéricas.

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