Identification of Chemical Processes for Control Purposes by Relay Techniques

  • C. Scali
Conference paper


A new identification technique (ATV+) for completely unknown processes is presented: it allows to build a parametric model from few experimental tests and to design a PID or Model Based Controller. It is also extended to open loop unstable processes and to multivariable processes. The method is compared with the original technique (ATV) and with simpler identification techniques in terms of ease of application, duration of tests and achievable performance.

Simulation results for the case of SISO processes, show that identification obtained by ATV+ technique allows superior performance, both for PID and for Model Based Controllers, thus compensating the longer identification times. In the MIMO case, ATV+ technique leads successfully to the design of decentralized controllers, but the improved knowledge of the system is not compensated by superiority in achievable performance.


Stable Oscillation Achievable Performance Automatic Tuning Unknown Process Closed Loop Response 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Italia, Milan 2002

Authors and Affiliations

  • C. Scali
    • 1
    • 2
  1. 1.Laboratorio di Controllo dei Processi Chimici(CPCLab)Università di PisaPisaItaly
  2. 2.Dipartimento di Ingegneria Chimica(DICCISM)Università di PisaPisaItaly

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