Predictive Functional Control (eBook)

Jaques Richalet was born in Versailles, France, in 1936. He studied aeronautical engineering at ENSAE in Paris and graduated in 1960. He then went to Berkeley, USA, where he obtained his MSc degree under the guidance of Prof. Zadeh. Back in Paris he worked in the field of applied mathematics and received his PhD in 1965. His interest in model-based predictive control started as early as 1968. In the same year he founded the process engineering consulting company ADERSA with a major breakthrough being the first commissioned application of model based predictive control to a binary distillation column in 1973. Since then he has been active in the areas of process identification, modelling and diagnosis methods such as predictive maintenance. Applications range from petrochemical and food industry to faster systems as encountered in the automotive and defense sector. He was a manager of ADERSA till 2001 and is still working as a consultant for modelling and predictive control. He now lives in Versailles in France. In his academic career he published more than fifty articles as well as three books on identification and predictive control. He has been president of the National Committee of Automatic Control and chairman of EEC Interest Group "CIDIC". For his achievements he was awarded the status as Chevalier de l'Ordre National du Merite and many researchers would probably agree to his being called "the grandfather of predictive control". He received the Nordic Process Control Award in 2007. He is now retired.

Series Editors’ Foreword 8
Foreword 10
Preface 11
Intended Audience 11
Reading Guide 12
Acknowledgments 13
Contents 15
Abbreviations and Symbols 20
1 Why Predictive Control? 22
1.1 “You would not drive your car using PID control” 22
1.2 Historical Context 23
1.3 Breaking with the PID Tradition 24
1.4 Impact on Industry 26
1.5 Objective 27
1.6 Predictive Control Block Diagram 29
1.7 Summary 30
2 Internal Model 31
2.1 Why Is Prediction Necessary? 31
2.2 Model Types 32
2.3 Decomposition of Unstable or Non-asymptotically Stable Systems 35
2.4 Prediction 38
2.5 Summary Summary Summary 40
3 Reference Trajectory 42
3.1 Introduction 42
3.2 Reference Trajectory 43
3.3 Pure Time Delay 45
3.4 Summary 48
4 Control Computation 49
4.1 Elementary Calculation 49
4.2 No Integrator? 52
4.3 Basis Functions Functions Functions 54
4.4 Extension 59
4.5 Implicit Regulator Calculation 59
4.6 Control of an Integrator Process 61
4.7 Feedforward Compensation 63
4.8 Extension: MV Smoothing 72
4.9 Convolution Representation 74
4.10 Extension to Higher-order System Models 76
4.11 Controller Initialisation 84
4.12 Summary 86
5 Tuning 88
5.1 Regulator Objectives 88
5.2 Accuracy 89
5.3 Dynamics 90
5.4 Robustness 94
5.5 Choice of Tuning Parameters 96
5.6 Gain Margin as a Function of CLTR (First-order System) 101
5.7 Tuning 102
5.8 The Tuner’s Rule 106
5.9 Practical Guidelines 108
5.10 Summary 109
6 Constraints 110
6.1 Benefit 110
6.2 MV Constraints 111
6.3 Internal Variable Constraints 113
6.4 Constraint Transfer Back Calculation 117
6.5 Summary 119
7 Industrial Implementation 120
7.1 Implementation 120
7.2 Zone Control 121
7.3 Cascade Control 124
7.4 Transparent Control 125
7.5 Shared Multi-MV Control 127
7.6 Estimator 134
7.7 Non-linear Control 139
7.8 Scenario Method 143
7.9 2MV/2CV Control 144
7.10 Summary 150
8 Parametric Control 151
8.1 Parametric Instability 151
8.2 Heat Exchanger 152
8.3 Constraint Transfer in Parametric Control 157
8.4 Evaluation 159
8.5 Summary 160
9 Unstable Poles and Zeros 161
9.1 Complexity 161
9.2 Stable Pole and Stable Zero 163
9.3 Unstable Zero and a Stable Pole 164
9.4 Control of an Unstable, Minimum Phase Process 165
9.5 Control of an Unstable, Non-minimum Phase Process 166
9.6 Summary 172
10 Industrial Examples 173
10.1 Industrial Applications 173
10.2 Heat Exchanger 174
10.3 Institut de Régulation d’Arles Exchanger 184
10.4 ARCELOR 193
10.5 EVONIK.DEGUSSA 213
10.6 Summary 216
11 Conclusions 217
11.1 Characteristics of PFC Control 218
11.2 Limits of PFC Control 219
11.3 Final Remark 221
Appendix A 222
A.1 First-Order Process (K,T,D) in MATLAB 222
Appendix B 231
B.1 Calculation of Heat-Transfer Coefficient for Water 231
References 233
Index 234