Auto-tuning of FOPI Controllers for TITO Processes with Experimental Validation

  • Gargi BaruahEmail author
  • Somanath Majhi
  • Chitralekha Mahanta
Research Article


In this paper, the auto-tuning of a fractional order proportional and integral (FOPI) controller is proposed and experimentally validated for two-input two-output (TITO) processes. The proposed method first identifies an unknown TITO plant into fractional order TITO model with time delay. Furthermore, decoupling the TITO process into two fractional order single-input single-output (SISO) transfer function models makes it easier for designing the decentralized FOPI controllers. The proposed control method is a generalization of both integer order and fractional order TITO systems depending on the value of the order of the model. One advantage of this method is the non-requirement of a-priori information of gain and phase crossover frequencies of the system while tuning the controllers. The proposed algorithm is validated both by simulation of a class of TITO process models as well as by experimental analysis of a coupled tank system (CTS).


Auto-tuning fractional order proportional and integral (FOPI) two-input two-output (TITO) robust relay with hysteresis model reduction coupled tank system (CTS) 


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Copyright information

© Institute of Automation, Chinese Academy of Sciences and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Electronics and Electrical EngineeringIndian Institute of Technology GuwahatiGuwahatiIndia

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