“Modified Smith-predictor multirate control utilizing secondary process measurements”

Authors: Rolf Ergon,
Affiliation: Telemark University College
Reference: 2007, Vol 28, No 1, pp. 15-18.

Keywords: Smith-predictor, secondary outputs, multirate control

Abstract: The Smith-predictor is a well-known control structure for industrial time delay systems, where the basic idea is to estimate the non-delayed process output by use of a process model, and to use this estimate in an inner feedback control loop combined with an outer feedback loop based on the delayed estimation error. The model used may be either mechanistic or identified from input-output data. The paper discusses improvements of the Smith-predictor for systems where also secondary process measurements without time delay are available as a basis for the primary output estimation. The estimator may then be identified also in the common case with primary outputs sampled at a lower rate than the secondary outputs. A simulation example demonstrates the feasibility and advantages of the suggested control structure.

PDF PDF (191 Kb)        DOI: 10.4173/mic.2007.1.2

DOI forward links to this article:
[1] Zdenek Hurak and Martin Rezac (2010), doi:10.1109/CDC.2010.5717039
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  title={{Modified Smith-predictor multirate control utilizing secondary process measurements}},
  author={Ergon, Rolf},
  journal={Modeling, Identification and Control},
  publisher={Norwegian Society of Automatic Control}