Selection of Controller Structure

  • B. D. Tyreus


In working with control system design for a multivariable process the terms control strategy, control structure, and controller structure are sometimes used interchangeably. They then mean the selection and pairing of controlled and manipulative variables to form a complete, functional control system. However, the three terms can also be taken to have their own individual meaning. In this case control strategy describes how the main loops in a process are to be set up in order to meet the overall objectives. For example, if the objective of a column is to produce a bottoms product stream, the control strategy to insure the purity of the product might be to use reboiler heat to keep the impurities out. Control structure, on the other hand, is the selection of controlled and manipulated variables from a set of many choices.


Control Valve Inventory Control Controller Structure Manipulative Variable Dynamic Degree 


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Copyright information

© Van Nostrand Reinhold 1992

Authors and Affiliations

  • B. D. Tyreus
    • 1
  1. 1.E. I. Du Pont de Nemours & Co.USA

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