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Vol: 51(65) No: 2 / June 2006        

State Estimation of a Wastewater Treatment Process Using a Sliding-Mode Observer
Marian Barbu
Department of Automatic Control, "Dunarea de Jos" University of Galati, Domneasca Street No.47, 800008 Galati, Romania, phone: (+40) 236-460182, e-mail: Marian.Barbu@ugal.ro
Sergiu Caraman
Department of Automatic Control, "Dunarea de Jos" University of Galati, Domneasca Street No.47, 800008 Galati, Romania, phone: (+40) 236-460182, e-mail: Sergiu.Caraman@ugal.ro


Keywords: state estimation, sliding mode, equivalent control, wastewater treatment, activated sludge.

Abstract
This paper deals with the state estimator process in the field of wastewater treatment with activated sludge. As is very well known, literature shows that the wastewater treatment processes are characterized by parametric uncertainties and measuring noise. In the present paper a robust method for non-linear systems state estimation is used: the sliding-mode observer. This kind of observer was developed based on the equivalent control method and it has an important advantage: the necessity of tuning a small number of parameters.

References
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