Tracking unmodelled signals of nonlinear systems via robust sliding mode observer: application to reacting systems

 

R. Aguilar-López^1,2 G. Soto-Cortés¹, M.I. Nería-González² & R. Escarela-Pérez¹

 

¹Departamento de Energía, Universidad Autónoma Metropolitana-Azcapotzalco, Av. San Pablo No. 180, Reynosa-Tamaulipas, 02200; Azcapotzalco, México, D.F. MEXICO E-mail.- raguilar@correo.azc.uam.mx , Fax.- + (52) 5394 7378.

²Departamento de Biotecnología y Bioingeniería. CINVESTAV-IPN.

 

Abstract

The problem of the on-line estimation of the reaction heat in a continuous stirred tank reactor from temperature measurements is addressed in this paper. The proposed uncertainty observer is based on differential algebraic techniques, such that the algebraic observability condition of the uncertainty from noisy temperature measurements is easily verified and the observer structure is very simple, which lead to feasible implementation. The observer proposed is robust against noisy measurements and sustained disturbances. The good performance of the observer is shown by means of numerical simulations.

Keywords: uncertainty observer, noisy measurements, sustained disturbances, robustness.

 

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