1、Control Loop FoundationBatch and Continuous ProcessesControl LoopFoundationBatch and Continuous ProcessesTerrence BlevinsMark NixonNoticeThe information presented in this publication is for the general education of the reader. Because neither the author(s) nor the publisher has any control over the
2、use of the information by the reader, both the author(s) and the publisher disclaim any and all liability of any kind arising out of such use. The reader is expected to exercise sound professional judgment in using any of the information presented in a particular application.Additionally, neither th
3、e author(s) nor the publisher has investigated or considered the effect of any patents on the ability of the reader to use any of the information in a particular application. The reader is responsible for reviewing any possible patents that may affect any particular use of the information presented.
4、Any references to commercial products in the work are cited as examples only. Neither the author(s) nor the publisher endorses any referenced commercial product. Any trademarks or tradenames referenced belong to the respective owner of the mark or name. Neither the author(s) nor the publisher makes
5、any representation regarding the availability of any referenced commercial product at any time. The manufacturers instructions on use of any commercial product must be followed at all times, even if in conflict with the information in this publication.Copyright 2011 International Society of Automati
6、onAll rights reserved. 67 Alexander DriveP.O. Box 12277Research Triangle Park, NC 27709Printed in the United States of America. 10 9 8 7 6 5 4 3 2ISBN 978-1-936007-54-7No part of this work may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechan
7、ical, photocopying, recording or otherwise, without the prior writ-ten permission of the publisher.Library of Congress Cataloging-in-Publication Data is in process.DedicationThis book is dedicated to Karen Blevins and Nancy Nixon, who have provided encouragement and support throughout our careers.vi
8、iAcknowledgmentsThe authors wish to express their appreciation to Grant Wilson for supporting work on this book and to Duncan Schleiss, John Berra, Bud Keyes, Ron Eddie, Tom Aneweer, Steve Boyce, Darrin Kuchle, John Caldwell, Dennis Stevenson, Willy Wojsznis, Mike Sheldon, David Holmes, Bob Lenich,
9、Tim Prickette, Dave Deitz, Craig Sydney, Jim Siemers, Mark Dimmitt, Jim Hoffmaster and Gil Pareja from Emerson Process Management for their inspiration and support of process control initiatives. In our work, we have benefited from communications with Karl strm from Lund University, Tom Edgar from t
10、he University of Texas, and Dale Seborg from the University of California, Santa Barbara on both basic and advanced control topics. The authors wish to thank Jim Cahill and Deborah Franke for their guidance in the design of the web site for this book and Brenda Forsythe and Jim Sipowicz for the crea
11、tive book cover design. We want to thank Karen Blevins, Mark Sowell, Professor Tom Edgar, Greg McMillan, and Scott Bogue for their review inputs, and to thank Susan Colwell, Manager, Publications Development, ISA, for her support in the publication of this book.Over the years, we have benefited from
12、 working with many others in the design and implementation of control systems. It was an honor to work with Greg Gra-ziadio, Puffer Sweiven Inc.; his influence can be seen in some of the application examples included in this book. Our early work on control projects and the devel-opment of control te
13、chniques for ammonia and pulp and paper processes was encouraged by Bruce Duncan, Sheldon Lloyd, Chuck Schuder, Charlie Brez, Bob Otto, John Hedrick, Tom Bell, Sid Smith, Rick Genter, Ken Langley, and Dick See-mann of Emerson Process Management. We also gratefully acknowledge the sup-port of the man
14、y customers we have worked with on control projects. In particular, the following individuals supported the pursuit of new control appli-cations and control technologies: Harry Pinder, Chris Liakos, Roger Smith, Bobby Deaton, Howard Lane, Mike Donohoe, George Wallace, and Roger Nesbit, Georgia Pacif
15、ic; Eric Striter, GE; Paul Friedman, Allied Chemical; David Taylor, Dow; Howard Bickley, Union Camp; James Beall and John Traylor, Texas Eastman; Robert Chamberlain and Bob Michelson, MacMillan Bloedel Limited; George Fink, US Borax; Mark Sowell and Greg McMillan, Solutia; Romeo Ancheta, Husky Energ
16、y; Derrick Vanderkraats, Canfor; Bruce Johnson and Efren Hernandez, Lubrizol; and Bruce Eldridge, Frank Seibert, and Robert Montgomery, University of Texas, Austin, Pickle Research Center. It has been gratifying to work with Terry Chmelyk, Saul Mtakula, and the rest of Norpacs control group in field
17、 testing new control technologies. The lime kiln example in this book reflects some of their work in this area. We greatly appreci-ate the support of Dave Wall, Don Umbach, John Peterson, and the rest of the Norpac management team and their passion for process control. We also wish to thank Mike Beg
18、in and the folks at Spartan Controls; Dan Moody and Harley Jef-fery, ControlSouthern; and Randy Angelle, John H. Carter Co. for their continued support throughout our careers.ixAbout the AuthorsTerrence “Terry” Blevins has been actively involved in the application and design of process control syste
19、ms throughout his career. For more than 15 years, he worked as a systems engineer and group manager in the design and startup of advanced control solutions for the pulp and paper industry. Terry was instru-mental in the establishment of Emerson Process Managements Advanced Con-trol Program. From 199
20、82005, Terry was the team lead for the development of DeltaV advanced control products. He is the Fieldbus Foundation team lead for the development and maintenance of the Function Block Specification and editor of the SIS Architecture and Model Specifications. In this capacity, Terry is involved in
21、the movement of Fieldbus Foundation function block work into inter-national standards. Terry is the U.S. expert to the IEC SC65E WG7 function block committee that is responsible for the IEC 61804 function block standards. He is a voting member and chairman of ISA104-EDDL (Electronic Device Descripti
22、on Language) committee and is the technical advisor to the United States Technical Advisory Group (USTAG) for the IEC65E subcommittee. He is also a member of the USNC TAG (IEC/SC65 and IEC/TC65). Terry authored “An Overview of the ISA/IEC Fieldbus,” Section 11, Standards Overview, Fifth Edition of t
23、he Process/Industrial Instruments and Controls Handbook and coauthored four sections in the Fourth Edition of the Instrumentation Engineers Handbook, Process Control and Opti-mization. He coauthored the ISA bestselling book Advanced Control Unleashed. He has 36 patents and has written over 65 papers
24、 on process control system design and applications. Terry received a Bachelor of Science in Electrical Engineering from the University of Louisville in 1971 and a Master of Science in Electrical Engineering from Purdue University in 1973. In 2004, he was inducted into Con-trol Magazines Process Auto
25、mation Hall of Fame. Presently, Terry is a principal technologist in the future architecture team of DeltaV Product Engineering at Emerson Process Management.Phone: (512) 418-4628 E-mail: Mark Nixon has been involved in the design and development of control systems throughout his career. Mark starte
26、d his career as a systems engineer working on projects in oil thus, it is important to have well-trained engi-neers and technicians to support such systems. Control Loop Foundation Batch and Continuous Processes has been authored by Terry Blevins and Mark Nixon of Emerson Process Management to provi
27、de staff in operat-ing plants with introductory training that does not require a high level of mathematics and simulation knowledge. I read this book with great inter-est because I have known both of the authors since the mid-1990s, and my students and I have interacted with them in several process
28、control research projects. In addition, I have co-authored several editions of the leading process control textbook, Process Dynamics and Control, Dale E. Seborg, Thomas F. Edgar, and Duncan A. Mellichamp during that same period of time. It is remarkable that Control Loop Foundation Batch and Contin
29、uous Processes so ably complements the textbook used in many uni-versity chemical engineering departments. Terry Blevins and Mark Nixons book is written at such a level that plant operations and technical personnel can easily relate to the content because of its practical orienta-tion. The book will
30、 also help plant technical staff to integrate the many dis-parate pieces of information they know about process control loops so that they can have a unified view of instrumentation, field communications, control strategies, process dynamics, loop tuning and performance, com-plex control systems, an
31、d practical control applications. The style of the materials presentation is well-adapted to individual study, and the authors have also included workshops and application examples that xviii CONTROL LOOP FOUNDATION: BATCH AND CONTINUOUS PROCESSESreaders with web access may interactively work with t
32、o develop an intui-tive feel for the dynamic behavior of typical control loops. I congratulate the authors on this impressive achievement and believe it will have con-siderable impact in those operating plants where it is used.Thomas F. EdgarUniversity of Texas - Austin11IntroductionThis book origin
33、ally started as a special class for new engineers within one of Emerson Process Managements engineering divisions, but has since grown in both scope and depth of material that is addressed. There are many aspects of process control systems, and the book is structured to allow engineers, managers, te
34、chnicians, and others that are new to process control to get up to speed more quickly on process control and related areas. Experienced control engineers will benefit from the application examples and workshops on process control design and implementation of multi-loop control strategies.The materia
35、l is presented in a manner that is independent of the control system manufacturer. The background material included in the first part of the book will be helpful to a new engineer who is just starting in this field and perhaps has never worked in a plant environment. Much of the material presented o
36、n the practical aspects of control system design and process applications is typically not included in process control taught at the university level. Many of the topics that are addressed in the book are areas that the authors have learned through hands-on experience gained while working in the des
37、ign and commissioning of process control systems. Also, we have benefited from the insight of many people working in process con-trol. This is a good way to learn, but its maybe not always the best or most efficient way to become proficient in these areas. Our goal, then, is to address concepts and
38、terminology that an engineer needs when working in the process industry. We hope that this information will provide help-ful insight as you look at a specific control system and how its used, and how best to use this equipment while addressing the different application 2 CONTROL LOOP FOUNDATION: BAT
39、CH AND CONTINUOUS PROCESSESrequirements. Whether you are working as a process control engineer in a manufacturing plant, working in a controls group in an engineering department, or working in an instrumentation department within a manu-facturing plant, we hope the information provided here will hel
40、p you in your work and will set a solid foundation that allows you to confidently address new control applications in the future.A lot has changed in the process industry over the last 30 some-odd years since we first started work as process control engineers. When we first started working with proc
41、ess control systems, as an engineer you often had an opportunity to see the whole projectworking with the plant, developing the controls strategy, documentation, and user interface, and then commissioning the system. In some cases, this involved modifying the control system software and hardware req
42、uired to support the control strategy. This opportunity existed because at that time, the control groups were often small and were focused on supporting plant operations. In some cases, youd be given a plane ticket, travel to the plant site, discuss the applications requirements, come back to the of
43、fice to develop the pro-cess control strategy and user interface, and then return to the plant to commission the control system. The ultimate measure of success was whether the plant was happy with the systems performance and with the benefits realized as a result of improved plant efficiency or thr
44、oughput. As an engineer, you also had the personal satisfaction of providing the opera-tors with better tools to manage and improve plant performance.Today, many control system design organizations are much bigger; thus, it is possible for a person working on some aspects of a control system not to
45、be involved in operator training or the commissioning of the control system. This is unfortunate since in that case you dont have an opportu-nity to see the full picture of how things fit together or to get direct and immediate feedback on how well a new or updated control system per-formed and whet
46、her it was necessary to make changes in the field to meet plant operators or managements operational requirements. So, the appli-cation examples in each chapter are designed to help you gain an appreci-ation for all aspects of the design, implementation, and commissioning of a control system.The boo
47、ks background material is organized so that new concepts build on material presented in previous sections. As you read the book, we sug-gest you cover the material in the order it is presented. If you have worked with control systems in the past, then the first part of the book may cover material yo
48、u already know. Even so, it would be a good idea to at least review those chapters. Many of the terms introduced in the first portion of the book are defined to establish a basis for understanding, which will be required to appreciate and apply the material on control system design CHAPTER 1 INTRODU
49、CTION 3and implementation presented in later sections of the book. Also, this background material is intended to promote an appreciation for the way in which many of the terms and concepts that form the foundation of industrial process control have evolved over time and through the efforts of many people involved in control system design and implementation. An understanding of these terms and why they have been traditionally described in a certain way can be helpful when considering the best way to meet the requirements of a new process. A
