Temperature Control of Continuous Chemical Reactors Under Noisy Measurements and Model Uncertainties

 

Ricardo Aguilar López*¹, Rafael Martínez Guerra², Juan L. Mata Machuca³

 

¹ Departamento de Biotecnología y Bioingeniería.

² Departamento de Control Automático CINVESTAV-IPN Av. I.P.N. No. 2508, San Pedro Zacatenco, México, D.F. C.P. 07360, MEXICO. *E-mail: raguilar@cinvestav.mx

 

ABSTRACT

The aim of this paper is to present the synthesis of a robust control law for the control of a class of nonlinear systems named Liouvillian. The control design is based on a sliding-mode uncertainty estimator developed under the framework of algebraic-differential concepts. The estimation convergence is done by the Lyapunov-type analysis and the closed-loop system stability is shown by means of the regulation error dynamics. Robustness of the proposed control scheme is tested in the face of noise output measurements and model uncertainties. The performance of the proposed control law is illustrated with numerical simulations in which a class of oscillatory chemical system is used as application example.

Keywords: I/O linearizing controller, sliding-mode observer, uncertainty estimation, noisy measurements.

 

RESUMEN

El objetivo de este artículo es presentar la síntesis de una ley de control robusta para una clase de sistemas no lineales denominados Liouvilianos. El diseño de control esta basado en un estimador de incertidumbres de modos deslizantes, desarrollado bajo el enfoque de conceptos algebraico-diferenciales. La convergencia del estimador se realiza mediante el método de Lyapunov y la estabilidad del sistema en lazo cerrado se demuestra mediante la dinámica del error de regulación. La robustez del esquema de control propuesto se determina tomando en cuenta la presencia de ruido en la salida del sistema e incertidumbres en el modelo. El desempeño de la ley de control propuesta se ilustra con simulaciones numéricas, donde se considera una clase de sistema químico oscilatorio como ejemplo.

 

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