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Comprehensive Theory with Solved Examples and Practice Questions Instrumentation and Process Control Chemical Engineering Publications
Comprehensive Theory
with Solved Examples and Practice Questions
Instrumentation and Process Control
ChemicalEngineering
Publications
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Instrumentation and Process Control© Copyright, by MADE EASY Publications Pvt. Ltd.All rights are reserved. No part of this publication may be reproduced, stored in or introduced into a retrieval system, or transmitted in any form or by any means (electronic, mechanical, photo-copying, recording or otherwise), without the prior written permission of the above mentioned publisher of this book.
First Edition : 2021
© All rights reserved by MADE EASY PUBLICATIONS PVT. LTD. No part of this book may be reproduced or utilized in any form without the written permission from the publisher.
Publications
Chapter 1Introduction ............................................. 11.1 Open Loop Control Systems ................................................... 1
1.2 Closed Loop Control Systems ................................................. 2
1.3 Comparison Between Open Loop and
Closed Loop Control Systems ................................... 3
1.4 Laplace Transformation ............................................................ 3
1.5 Transfer Function and Impulse Response Function ....... 8
1.6 Standard Test Signals ...............................................................10
1.7 Poles and Zeros of a Transfer Function ..............................11
1.8 Properties of Transfer Function ............................................13
1.9 Methods of Analysis .................................................................14
Student’s Assignments ..............................................................16
Chapter 2Dynamic Behaviour of First
and Second Order System .....................202.1 Introduction ................................................................................20
2.2 Transient and Steady State Response ................................20
2.3 Steady State Error ......................................................................21
2.4 Transients State Analysis .......................................................23
2.5 Time Response of a Second Order Control System ......30
2.6 Need of a Mathematical Modelling ....................................50
2.7 State Variables and State Equations
for Chemical Process ..................................................50
2.8 Continuous Stirred Tank Reactor (CSTR) ...........................51
2.9 First Order System .....................................................................56
2.10 Second Order System ..............................................................60
2.11 Multicapacity Process (as second order systems)..........62
2.12 Dead Time in a Process ............................................................65
Student’s Assignments ..............................................................68
Chapter 3Close Loop Transfer Functions ..............753.1 Process ........................................................................................75
3.2 Automatic Control ....................................................................76
3.3 Feed Forward Control Technique ........................................77
3.4 Block Diagrams : Fundamentals ...........................................78
3.5 Block Diagram of a Closed-loop System ...........................79
3.6 Block Diagram Transformation Theorems ........................81
3.7 Feedback Control ......................................................................91
3.8 Types of Feedback Controllers .............................................93
3.9 Closed Loop Response Block Diagram ..............................96
3.10 Composite Control Actions ................................................ 102
Student’s Assignments ........................................................... 104
Chapter 4Controller and Advanced Control Strategies .............................................1084.1 Industrial Controllers ............................................................ 108
4.2 Proportional (P) Controller .................................................. 109
4.3 Integral (I) Controller (Reset Mode) ..........................................110
4.4 Derivative (D) Controller (Rate Mode) ............................ 111
4.5 Proportional Integral (P-I) Controller .............................. 113
4.6 Proportional Derivative (P-D) Controller........................ 114
4.7 Proportional Integral Derivative (P-I-D) Controller .... 114
4.8 Cascade Control ...................................................................... 115
4.9 Feed Forward Control ........................................................... 122
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4.10 Designing of Feedback Controllers ................................. 125
4.11 Controller Tuning ................................................................... 129
4.12 Controlling Elements ............................................................ 130
Student’s Assignments ........................................................... 136
Chapter 5Stability and Frequency Analysis
of Control Systems ..............................1395.1 The Concept of Stability ...................................................... 1395.2 Frequency Analysis of Control Systems ......................... 1525.3 Advantages of Frequency Response ............................... 152
5.4 Frequency Response Analysis of
Second Order Control System ....................................................153
5.5 Correlation between Step Response and Frequency
Response in the Standard Order System ..............................155
5.6 Frequency Domain Analysis of Dead Time or
Transportation Lag Elements .....................................................156
5.7 Relative Stability: Gain Margin and Phase Margin ............158
5.8 Gain Margin and Phase Margin for
Second Order Control System ....................................................159
5.9 Bode Plots ............................................................................................163
Student’s Assignments ........................................................... 165
Chapter 6Sensors, Transducers and P & ID Symbol .......................................1716.1 Introduction ............................................................................. 171
6.2 Sensor ..................................................................................... 171
6.3 Transducer ................................................................................ 171
6.4 Sensor/transducers specifications ................................... 172
6.5 Classification of sensors ....................................................... 174
6.6 Equipment Symbols .............................................................. 176
6.7 Piping Symbols ....................................................................... 177
6.8 Instrument symbols .............................................................. 178
6.9 Valve Symbols.......................................................................... 179
Student’s Assignments ........................................................... 180
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