Process Identification and PID Control

425 Pages·2009·2.26 MB·English

by  Su Whan Sung, Jietae Lee, In-Beum Lee

PROCESS IDENTIFICATION
AND PID CONTROL
Su Whan Sung
Jietae Lee
Kyungpook National University, Republic of Korea
In-Beum Lee
Pohang University of Science and Technology, Republic of Korea
PROCESS IDENTIFICATION
AND PID CONTROL
PROCESS IDENTIFICATION
AND PID CONTROL
Su Whan Sung
Jietae Lee
Kyungpook National University, Republic of Korea
In-Beum Lee
Pohang University of Science and Technology, Republic of Korea
Copyright # 2009 John Wiley & Sons (Asia) Pte Ltd, 2 Clementi Loop, # 02-01,
Singapore 129809
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Contents
Preface xi
Part One Basics of Process Dynamics 1
1 Mathematical Representations of Linear Processes 3
1.1 Introduction to Process Control and Identification 3
1.2 Properties of Linear Processes 9
1.3 Laplace Transform 16
1.4 Transfer Function and State-Space Systems 32
Problems 38
2 Simulations 45
2.1 Simulating Processes Composed of Differential Equations 45
2.2 Simulating Processes Including Time Delay 50
2.3 Simulating Closed-Loop Control Systems 57
2.4 Useful Numerical Analysis Methods 59
Problems 74
3 Dynamic Behavior of Linear Processes 79
3.1 Low-Order Plus Time-Delay Processes 79
3.2 Process Reaction Curve Method 84
3.3 Poles and Zeroes 86
3.4 Block Diagram 92
3.5 Frequency Responses 94
Problems 103
Part Two Process Control 109
4 Proportional–Integral–Derivative Control 111
4.1 Structure of Proportional–Integral–Derivative Controllers
and Implementation in Computers/Microprocessors 111
4.2 Roles of Three Parts of Proportional–Integral–Derivative Controllers 122
4.3 Integral Windup 129
viii Contents
4.4 Commercial Proportional–Integral–Derivative Controllers 135
Problems 147
5 Proportional–Integral–Derivative Controller Tuning 151
5.1 Trial-and-Error Tuning 151
5.2 Simple Process Identification Methods 154
5.3 Ziegler–Nichols Tuning Rule 157
5.4 Internal Model Control Tuning Rule 159
5.5 Integral of the Time-Weighted Absolute Value of the Error Tunning Rule
for a First-Order Plus Time-Delay Model (ITAE-1) 161
5.6 Integral of the Time-Weighted Absolute Value of the Error Tunning Rule
for a Second-Order Plus Time-Delay Model (ITAE-2) 166
5.7 Optimal Gain Margin Tuning Rule for an Unstable Second-Order
Plus Time-Delay Model (OGM-unstable) 169
5.8 Model Reduction Method for Proportional–Integral–Derivative
Controller Tuning 170
5.9 Consideration of Modeling Errors 196
5.10 Concluding Remarks 196
Problems 197
6 Dynamic Behavior of Closed-Loop Control Systems 201
6.1 Closed-Loop Transfer Function and Characteristic Equation 201
6.2 Bode Stability Criterion 203
6.3 Nyquist Stability Criterion 207
6.4 Gain Margin and Phase Margin 210
Problems 212
7 Enhanced Control Strategies 215
7.1 Cascade Control 215
7.2 Time-Delay Compensators 217
7.3 Gain Scheduling 225
7.4 Proportional–Integral–Derivative Control using Internal
Feedback Loop 228
Problems 231
Part Three Process Identification 233
8 Process Identification Methods for Frequency Response Models 235
8.1 Fourier Series 235
8.2 Frequency Response Analysis and Autotuning 240
8.3 Describing Function Analysis 241
8.4 Fourier Analysis 247
8.5 Modified Fourier Transform 250
8.6 Frequency Response Analysis with Integrals 261
Problems 271