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Conference Contribution

Transfer Function Parameter Identification by Modified Relay Feedback

Kristian Soltesz, Tore Hägglund, Karl Johan Åström

Abstract

This paper proposes a transfer function parameter identification method, applicable to SISO systems of any order. Parameter identification is posed as a (non-convex) squared output error minimization problem, numerically solved utilizing Newton-Raphson iteration with back tracking line search. Focus lies on computing the cost function gradient and Hessian with respect to the parameter vector and on finding a feasible start point. The method is demonstrated for FOTD model identification. A modified relay non-linearity is utilized in order to obtain most input signal energy at a predefined phase, without a priori system information. The identification method is evaluated on a batch of common process industry processes. Finally, conclusions and suggestions on future work are provided.

Keywords

relay, identification, parametric, transfer function, state space, FOTD

Links

http://www.control.lth.se/database/publications/article.pike?artkey=solacc10


In Proc. American Control Conference 2010, In 2010 American Control Conference, Baltimore, Maryland, USA, June 2010.

 
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