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.


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  1. Buckley, P. S. (1964). Overall process control. Techniques of Process Control New York: Wiley, Chapter 13.Google Scholar
  2. Downs, J. J. and Doss, J. E. (1991). Present status and future needs—A view from North American industry. Paper presented at the Fourth International Conference on Chemical Process Control, CPC IV, South Padre Island, 1991.Google Scholar
  3. Fisher, W. R., Doherty, M. F., and Douglas, J. M. (1988). The interface between design and control. 3. Selecting a set of controlled variables. Ind. Eng. Chem. Res. 27, 611.CrossRefGoogle Scholar
  4. Shinskey, F. G. (1985). Disturbance-rejection capabilities of distillation control systems. Proceedings of the American Control Conference, Boston, MA, June 19–21.Google Scholar
  5. Skogestad, S., Jacobsen, E. W., and Lundstrom, P. (1990). Selecting the best distillation control structure. AIChE J. 36, 753–764.CrossRefGoogle Scholar
  6. Tyreus, B. D. (1987). Optimization and multivariable control of distillation columns. Proceedings of the ISA-87, Anaheim, California.Google Scholar
  7. Waller, K. V., Finnerman, D. H., Sandelin, P. M., Haggblom, K. E., and Gustafsson, S. E. (1988a). An experimental comparison of four control structures for two-point control of distillation. Ind. Eng. Chem. Res. 27, 624.CrossRefGoogle Scholar
  8. Waller, K. V., Haggblom, K. E., Sandelin, P. M., and Finnerman, D. H. (1988b). Disturbance sensitivity of distillation control structures. AIChE J. 34, 853–858.CrossRefGoogle Scholar

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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