Process control fundamentals

Instrumentation & Control
Process Control Fundamentals

Table of Contents
Introduction..................................................................................................................................................... 1
Performance Objective............................................................................................................................. 1
The Importance of Process Control ............................................................................................................... 1
Learning Objectives.................................................................................................................................. 1
The Importance of ProcessControl................................................................................................................. 2
Process...................................................................................................................................................... 2
Process Control ........................................................................................................................................ 2Reduce Variability ............................................................................................................................. 2
Increase Efficiency ............................................................................................................................ 3
Ensure Safety..................................................................................................................................... 3
Control Theory Basics .................................................................................................................................... 4
Learning Objectives.................................................................................................................................. 4
The ControlLoop............................................................................................................................................. 5
Three Tasks...............................................................................................................................................5
Process Control Terms....................................................................................................................................6
Process Variable.......................................................................................................................................6
Setpoint .....................................................................................................................................................6
MeasuredVariables, Process Variables, and Manipulated Variables.....................................................7
Error .........................................................................................................................................................7Offset.........................................................................................................................................................8
Load Disturbance .....................................................................................................................................8
Control Algorithm.....................................................................................................................................8
Manual and Automatic Control................................................................................................................9
Closed and Open Control Loops ..............................................................................................................10
Components of Control Loops and ISA Symbology ...................................................................................... 11
Learning...