Smart Relay-Based Online Estimation of Process Model Parameters

  • Bajarangbali
  • Somanath Majhi
Conference paper
Part of the Advances in Intelligent Systems and Computing book series (AISC, volume 236)


This paper presents online estimation of unstable and integrating time delay process model parameters using a smart relay. The describing function (DF) approximation of relay not only results in simpler analytical expressions but also enables one to estimate the model parameters with significant accuracy. Measurement noise is an important issue during estimation of process model parameters. The smart relay is capable of emulating the dynamics of a conventional relay and also of rejecting the ill effects of measurement noise. Simulation results show the usefulness of the identification technique.


Relay Hysteresis Smart relay Process model 


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Copyright information

© Springer India 2014

Authors and Affiliations

  1. 1.Department of Electronics and Electrical EngineeringIndian Institute of TechnologyGuwahatiIndia

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