PROCESS CONTROLLER TUNING

FOR OPERATION IMPROVEMENT

WHY / HOW TO / WHEN TO / WHEN NOT TO

A Course for Technicians and Operators

COURSE DESCRIPTION

            This course will teach practical level controller tuning techniques which will improve process operations and consequently have a positive economic impact on the process.  The course begins discussing reasons why loop tuning is important. Then characteristics of control loop components that influence controller tuning are discussed.  This including process dynamics, valve characteristics, the controller itself and non-linearities and other phenomena which may be encountered.

            The main emphasis of the course, however, is on a practical method of improving "as found" controller tuning, also called "intelligent trial and error tuning".  Tuning for typical feedback loops, liquid level control loops and cascade loops is covered.

            The course also emphasizes how to recognize situations where loop tuning is not appropriate, since it has been observed that many technicians and operators attempt to tune a controller when the real problem lies elsewhere in the control loop.

            Computers, running a control loop simulation program, are used in the classroom to illustrate the concepts and to provide  realistic, hands-on practice.  This visualization and hands-on practice helps both the understanding and the long-term retention of the concepts presented.

INTENDED FOR

q       Instrumentation technicians or operators who are responsible for actual loop tuning in the plant.

q       Process or control system engineers who wish to improve their understanding and skill at loop tuning may also benefit from this course.

COURSE OUTLINE AND SCHEDULE

“PROCESS CONTROLLER TUNING FOR OPERATION IMPROVEMENT”

DAY 1             INTRODUCTION

      The importance of properly tuned loops

                        Loop components and their effect on controller tuning

                        Process, process dynamics

            Transmitters

            Valves

                          FEEDBACK CONTROL

                        Purpose and behavior of each of the modes

                        Proportional

            Integral

            Derivative

                        Demonstration Exercise: Proportional, integral and derivative

                        Terminology used by specific manufacturers

                        CONTROLLER TUNING OVERVIEW

                        What is "good" tuning?

                        Demonstration Exercise: Tuning for set point changes vs tuning for disturbances

                        Expected behavior of tuning parameter changes

                        CONTROLLER TUNING TECHNIQUES

                                   Tuning from open loop data

                                   Laboratory Exercise Open Loop Tuning

                                   Tuning from closed loop data

                                  Demonstration Exercise Closed Loop Tuning “Intelligent” trial and error tuning

                        Laboratory Exercise: Improving 'As Found' Tuning

DAY 2                        CONTROLLER TUNING TECHNIQUES (Continued)

                        Tuning Liquid Level Control Loops

                        Laboratory Exercise: Tuning liquid level control

                                    RECOGNIZING CONTROL LOOP PROBLEMS THAT ARE NOT

                                    CAUSED BY TUNING

                                   Situations where tuning in inappropriate

                        Laboratory Exercise: "To Tune or Not to Tune?"

                                               CONTROLLER TUNING FOR OTHER TYPES OF LOOPS

                       Ratio loops

                       Cascade loops

                       Laboratory Exercise: Tuning Cascade Loops

                                              MAINTAINING CONTROL OF TUNING

                                  Recommended form of documentation