Szederkényi, Gábor

Current Position

Research Professor
  Process Control Research Group
  Computer and Automation Research Institute
  Hungarian Academy of Sciences
  H-1518 Budapest
  P.O. Box 63., Kende u. 13-17.
  Tel:  (36) 1 279 6173 (office)
  Fax: (36) 1 466 7503
  E-mail: szeder@sztaki.hu

 

Professor
  Faculty of Information Technology and Bionics
  Pázmány Péter Catholic University
  H-1083 Budapest
  Práter u. 50/a

 

Research
Curriculum Vitae
List of publications

Research

Hangos, K. M., J. Bokor and G. Szederkényi:
Analysis and Control of Nonlinear Process Systems.
Springer-Verlag, London, pp. 1-308 (2004)


Model based diagnosis of nonlinear process systems
A method has been proposed for the analysis of model-based diagnosis algorithms of nonlinear process systems. Phyisical models have been used for the description of process dynamics and semi-empirical models have been used for the description of the fault phenomena. It has been shown that the performance of the fault detection and isolation algorithms is improving with the increasing level of detail of the process models [1]. It has been shown that safe simultaneous fault detection and isolation is possible using the grey- or white-box models of the faults together with the process model [2,3].

Analysis of nonlinear process systems
It has been shown that a wide class of fed-batch bioreactors is not controllable in the nonlinear sense when the manipulable input is the most frequently used inlet feed flow rate [4]. It has been computed using nonlinear coordinates transformations that the zero dynamics of isotherm continuous bioreactors is asymptotically stable in the case of several different reaction kinetics if the controlled output is the substrate concentration [5]. Using the analysis results, globally stabilizing nonlinear controllers have been designed for different kinds of bioreactors.

Hamiltonian description of process systems
It has been shown that a wide class of process systems can be represented in the Hamiltonian canonical form which is well-known from classical mechanics [6]. The conditions of the dissipative- Hamiltonian description of dynamical systems in quasi-polynomial form with a quadratic Hamiltonian function have been given. It has also been shown that the global stability of quasi-polynomial systems with the well-known entropy-like Lyapunov function is equivalent to the existence of this dissipative-Hamiltonian description [7].


Selected Publications

(from the Publication List)

[1] E. Weyer, G. Szederkényi, and K. M. Hangos. Grey box fault detection of heat exchangers. Control Engineering Practice 8 : pp. 121-131, 2000.

[2] G. Szederkényi, E. Weyer, K. M. Hangos. Simultaneous fault detection of heat exchangers. In IFAC Workshop on Fault Detection and Supervision in the Chemical Process Industries, Lyon, France, 1998, (editors: P. S. Dhurjati, S. Cauvin) pp 1-6.

[3] K. M. Hangos, G. Szederkényi. Grey box process modeling for fault detection and isolation. In European Control Conference (ECC’99), Karlsruhe, Germany, 1999, pp 1-6 (on CD).

[4] G. Szederkényi, M. Kovács, and K. M. Hangos. Reachability of nonlinear fed-batch fermentation processes. International Journal of Robust and Nonlinear Control 12 : pp. 1109-1124, 2002.

[5] G. Szederkényi, N. R. Kristensen, K. M. Hangos, and S. B. Joergensen. Nonlinear analysis and control of a continuous bioreactor. Computers and Chemical Engineering 26 : pp. 659-670, 2002.

[6] K. M. Hangos, J. Bokor, and G. Szederkényi. Hamiltonian view on process systems. AIChe Journal 47 : pp. 1819-1831, 2001.

[7] G. Szederkényi, and K. M. Hangos. Global stability and quadratic Hamiltonian structure in Lotka-Volterra and quasi-polynomial systems. Physics Letters A. 324 : pp. 437-445, 2004.