Servo Motors and Industrial Control Theory (eBook)

Series Preface 7
Preface 8
Contents 11
Feedback Control Theory 14
1.1 Linear System 14
1.2 Nonlinear Systems 15
1.3 Linearization Technique 16
1.4 Laplace Transform 17
1.5 Transfer Function 20
1.6 First Order Transfer Function 21
1.7 Frequency Response 23
1.8 Second Order Transfer Function 24
1.9 Block Diagram Representation 26
1.10 Frequency Response 28
1.11 Conclusion 29
Feedback Control Theory Continued 30
2.1 Introduction 30
2.2 Routh-Hurwitz Stability Criteria 30
2.3 Root Locus Method 32
2.4 Nyquist Plot 36
2.5 Bode Diagram 41
2.6 Steady State Error 52
State Variable Feedback Control Theory 55
3.1 Introduction 55
3.2 State Variables 56
3.3 Eigenvalues, Eigenvectors, and Characteristic Equation 59
3.4 State Variable Feedback Control Theory 62
3.5 Dynamic Observer 67
3.6 Controllability and Observability 68
3.7 Conclusion 70
Electrical DC Servo Motors 71
4.1 Types of DC Servo Motors 71
4.2 Types of Power Unit 72
4.3 Speed Torque Characteristic of DC Servo Motors 74
4.4 DC Servo Motors in Open and Closed Loop Velocity Control 75
4.5 DC Servo Motors in Closed Loop Position Control 78
4.6 DC Servo Motors for Very High Performance Requirements 80
4.7 Properties of Power Unit 89
Stepping Servo Motors 92
5.1 Principal Operation 92
5.2 Stepping Motors with Small Step Angle 94
5.3 Torque-Displacement Characteristic of a Stepping Motor 95
5.4 Dynamic Response Characteristic over One Step Movement 97
5.5 Speed-Torque Characteristic Behavior of Stepping Motors 98
5.6 Stepping Motors for Position Control Applications 99
AC Servo Motors 101
6.1 Principle of Operation 101
6.2 Variable Speed AC Motors 101
6.3 Mathematical Model 102
6.4 Frequency Converter 107
6.5 Conclusion 112
Electrohydraulic Servo Motors 113
7.1 Introduction 113
7.2 A Simple Mechanically Controlled Servo System 114
7.3 Electrohydraulic Servo Valves 117
7.4 Hydraulic Servo Motors 119
7.5 A Numerical Investigation of the Transient Behavior of an Electrohydraulic Servo Motor Under Different Conditions 122
7.6 Conclusion 127
Actuators Based on Electro-Rheological Fluid 129
8.1 Introduction 129
8.2 Some Possible Applications of ER Fluid 130
8.2.1 Valves 130
8.2.2 ER Clutch and Catch Type Actuators 130
8.2.3 Variable Dampers Based on ER Fluid 131
8.3 Properties of ER Fluid in Flow Mode 132
8.4 Properties of ER Fluid in Shear Mode 137
8.5 Conclusion 139
The Choice and Comparison of Servo Motors 141
9.1 Introduction 141
9.2 Theory and Performance Criteria 142
9.3 Comparison of Results and Design Procedure 145
9.4 An Example on Choosing a Servo Motor 155
9.5 Conclusion 156
Exercise Problems on Classical Feedback Control Theory (Chapters 1 and 2) 158
Appendix B Exercise Problems on State Variable Feedback Control Theory (Chapter 3) 182
Appendix C Exercise Problems on Servo Motors (Chapters 4-9) 205
C.1 Electrical DC Servo Motors 205
C.2 Electrical Stepping Servo Motors 217
C.3 Electrical AC Servo Motors 221
C.4 Electrohydraulic Servo Motors 224
C.5 Actuators based on Electro-Rheological Fluid (ERF) 228
C.6 Selection of a Servo Motor for Particular Applications 231
Index 232