Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published June 17, 1993 | public
Report Open

Robust Loopshaping for Process Control

Abstract

Strong trends in chemical engineering and plant operation have made the control of processes increasingly difficult and have driven the process industry's demand for improved control techniques. Improved control leads to savings in resources, smaller downtimes, improved safety, and reduced pollution. Though the need for improved process control is clear, advanced control methodologies have had only limited acceptance and application in industrial practice. The reason for this gap between control theory and practice is that existing control methodologies do not adequately address all of the following control system requirements and problems associated with control design: * The controller must be insensitive to plant/model mismatch, and perform well under unmeasured or poorly modeled disturbances. * The controlled system must perform well under state or actuator constraints. * The controlled system must be safe, reliable, and easy to maintain. * Controllers are commonly required to be decentralized. * Actuators and sensors must be selected before the controller can be designed. * Inputs and outputs must be paired before the design of a decentralized controller. A framework is presented to address these control requirements/problems in a general, unified manner. The approach will be demonstrated on adhesive coating processes and distillation columns.

Additional Information

I am deeply indebted to my Ph.D. advisor Manfred Morari for his support and guidance, and for allowing me considerable freedom in conducting this research while simultaneously exacting his very high standards. I am grateful to other people who have given me advice at various times in the last nine years: Octave Levenspiel and Keith Levien at Oregon State University while I was an undergraduate; Sigurd Skogestad at Norges Tekniske Høgskolein Trondheim, Norway during my stay there last summer, and Karl Åström at Lunds Tekniska Högskola in Lund, Sweden during his stay earlier this year at Caltech as a Fairchild Scholar. Thanks to the people who I have worked with in chemical, mechanical, and electrical engineering over the last few years: Morten Hovd, Dan Laughlin, Jay Lee, Andy Packard, Matthew Tyler, and Peter Young. I thoroughly enjoyed interacting with Ferdinand Pranckh and Luigi Sartor at Avery/Dennison Research Center in Pasadena in developing the adhesive coating controller for Avery/Dennison Company which is described in this thesis. I am happy for the friends I have made with students in Manfred Morari, John Doyle, and Sigurd Skogestad's groups, and around the world: Frank Allgöwer, Venkataramanan (Ragu) Balakrishnan, Carolyn Beck, Nikolaus Bekiaris, Hector Budman, Bobby Bodenheimer, Peter Campo, Frank Doyle, Håkan Hjalmarsson, Tyler Holcomb, Iftikhar Huq, Elling Jacobsen, Mayuresh Kothare, Frank Laganier, Lionel Laroche, Petter Lundström, Knut Mathisen, George Meski, John Morris, Al Moser, Matt Newlin, Simone Oliveira, Ricardo Peña, Carl Rhodes, Cris Radu, Doug Raven, Tony Skjellum, Mario Sznaier, Athanasios Tsirukis, Cris Webb, Zhi (Alex) Zheng. Outside the sphere of control research, I will remember my compatriots on the Graduate Review Board and the Chemical Engineering Softball Team, and my roommate and cycling partner Phil Lovalenti.

Files

CDS93-010.pdf
Files (20.6 MB)
Name Size Download all
md5:c3936d54e5b0d198307abd95092f9409
4.0 MB Download
md5:be87c37e2b232a9d0967522a8fc325b9
16.5 MB Preview Download

Additional details

Created:
August 20, 2023
Modified:
October 24, 2023