Electromagnetic and Electromechanical Machines

Preface
Acknowledgments
Chapter 1: Basic Concepts of Power Circuits
1-1 Phasor Diagrams
1-2 AC Circuit Relationships
1-2.1 Single-Subscript Notation
1-2.2 Double-Subscript Notation
1-3 Three-Phase Circuits
1-3.1 Delta-Connected Impedances
1-3.2 Balanced Delta-Connected Load
1-3.3 Wye-Connected Impedances
1-3.4 Three-Wire, Wye-Arrangement (Neutral Connection Open)
1-3.5 Balanced Wye-Connected Load
1-3.6 Four-Wire Arrangement (Load Neutral Connected to Source Neutral)
1-3.7 Phase Sequence
1-4 Complex Power
1-4.1 Power Triangle
1-4.2 Power Flow
1-4.3 Power in Balanced Three-Phase Circuits
1-5 Per-Unit Quantities
Study Questions
Problems
Bibliography
Chapter 2: Energy Conversion
2-1 Force in a Capacitor
2-2 The Toroid
2-3 Series and Parallel Magnetic Circuits
2-4 Magnetic Materials
2-5 Iron and Air
2-5.1 Magnetic Leakage and Fringing
2-5.2 Graphical Analysis
2-5.3 Core Losses
Hysteresis Loop
Hysteresis Loss
Reentrant Loop
Rotational Hysteresis Loss
Maximum Flux Density under Sinusoidal Excitation
Eddy-Current Loss
High-Frequency Magnetic Materials
2-6 Flux Linkage and Equivalent Flux
2-6.1 Energy Stored in Magnetic Circuits
2-6.2 Self-Inductance
2-6.3 Mutual Inductance
Coefficient of Coupling
2-7 Magnetic Force
2-7.1 Force and Torque in Singly Excited Magnetic Circuits
2-7.2 Force and Torque in Multiply Excited Magnetic Circuits
2-7.3 Force and Energy in Nonlinear Magnetic Circuits
Energy Relations in Nonlinear Magnetic Circuits
2-8 Permanent Magnets
2-8.1 Operating Characteristics of Permanent Magnets
2-8.2 Energy Product
2-8.3 Square-Loop Ferrites
Study Questions
Problems
Bibliography
Chapter 3: The Transformer
3-1 The Two-Winding Transformer
3-2 The Ideal Two-Winding Transformer
3-2.1 Voltage Ratio and Transformer Polarity
3-2.2 Current Ratio
3-2.3 Impedance Ratio
3-3 Exciting Current, Core-Loss Current and Magnetizing Current
3-3.1 Core-Loss Current
3-3.2 Magnetizing Current
3-3.3 Waveform of Exciting Current
3-3.4 Core-Loss Current
3-3.5 Magnetizing Current, Including Harmonics
3-4 Leakage Impedance
3-4.1 The Equivalent Circuit
3-4.2 The Approximate Equivalent Circuit
3-5 Coupled-Circuit Equations
3-5.1 Leakage Inductance
3-5.2 Magnetizing Inductance
3-5.3 Coefficient of Coupling
3-6 Open-Circuit and Short-Circuit Tests, Exciting Admittance, and Equivalent Impedance
3-7 Transformer Losses and Efficiency
3-8 Voltage Regulation
3-9 Autotransformers
3-10 Instrument Transformers
3-11 Three-Phase Transformer Connections
3-11.1 Delta-Delta Connection
3-11.2 Wye-Wye Connection
3-11.3 Wye-Delta Connection
3-11.4 Open-Delta or V-V Connection
3-11.5 Three-Phase Transformers
3-11.6 Three-to-Six-Phase Transformation
3-12 Per-Unit Quantities of Transformers
3-13 Multicircuit Transformers
3-13.1 Open-Circuit and Short-Circuit Tests
3-14 Third Harmonics in Three-Phase Transformer Operation
3-15 Current Inrush
3-16 Reactors
3-16.1 Volume of Air Gap
3-16.2 Rating of Reactors and Transformers
Study Questions
Problems
Bibliography
Chapter 4: Synchronous Machines
4-1 Introduction
4-2 Waveform
4-3 AC Armature Windings
4-4 Induced Armature Voltage
4-4.1 Voltage Induced in a Generator Armature Coil
4-4.2 Voltage Induced in a Distributed Winding
4-4.3 Pitch Factor and Breadth Factor for Harmonics
4-5 Armature MMF
4-5.1 Fundamental Component of mmf Space Wave
4-5.2 Angular Displacement between mmf Waves
4-6 Unsaturated Inductances of a Cylindrical-Rotor Machine
4-6.1 Inductance of the Field
4-6.2 Magnetizing Inductance (Inductance of Armature Reaction)
4-6.3 Self- and Mutual-Inductance Components of Magnetizing Inductance in Three-Phase Windings
4-7 Phasor Diagram of Cylindrical-Rotor Synchronous Generator
4-7.1 Leakage Flux
4-7.2 Synchronous Reactance
4-7.3 Equivalent Circuit
4-7.4 Current-Source Representation
4-8 Idealized Three-Phase Generator—General Relationship in Terms of Inductances
4-9 Generator Delivering Balanced Load
4-10 Torque
4-11 Open-Circuit and Short-Circuit Tests
4-11.1 Open-Circuit Characteristic
4-11.2 Short-Circuit Test
4-11.3 Unsaturated Synchronous Impedance
4-11.4 Approximation of the Saturated Synchronous Reactance
4-12 Voltage Regulation
4-13 Short-Circuit Ratio
4-14 Real and Reactive Power versus Power Angle
4-15 Synchronous-Motor V Curves
4-16 Excitation Systems for Synchronous Machines
4-16.1 Brushless Excitation System
4-17 Direct-Axis and Quadrature-Axis Synchronous Reactance in Salient-Pole Machines—Two-Reactance Theory
4-18 Zero-Power-Factor Characteristic and Potier Triangle
4-18.1 Graphical Determination of the Potier Triangle
4-18.2 Potier Reactance
4-19 Use of Potier Reactance to Account for Saturation
4-19.1 Saturation-Factor Method
4-20 Slip Test for Determining xd and xq
4-21 Torque-Angle Characteristic of Salient-Pole Machines
Power Associated with Iq
Power Associated with Id
Total Complex Power
4-22 Synchronous-Motor Starting
4-23 Features and Application of Synchronous Motors
Study Questions
Problems
Bibliography
Chapter 5: The Induction Motor
5-1 The Polyphase Induction Motor
5-2 Magnetizing Reactance and Leakage Reactance
5-2.1 Magnetizing Reactance
5-2.2 Leakage Reactance
5-3 Rotor Current and Slip
5-3.1 Induction Motor Slip
5-3.2 Rotor Current
5-4 Rotor Copper Loss and Slip
5-5 Equivalent Circuit of the Polyphase Wound-Rotor Induction Motor
5-5.1 Approximate Equivalent Circuit with Adjusted Voltage
5-5.2 Mechanical Power and Torque
5-5.3 Phasor Diagram of the Polyphase Wound-Rotor Induction Motor
5-6 Polyphase Squirrel-Cage Induction Motor
5-6.1 Transformation Ratio of the Squirrel-Cage Induction Motor
5-6.2 Double-Squirrel-Cage and Deep-Bar Motors
5-6.3 Equivalent Circuits for Multiple-Cage Polyphase Induction Motors
5-6.4 Skewing
5-7 No-Load and Locked-Rotor Tests
No-Load Test
Locked-Rotor Test
5-8 Polyphase-Induction Motor-Slip-Torque Relationship Based on Approximate Equivalent Circuit
5-8.1 Starting Torque
5-8.2 Maximum Torque
5-8.3 Influence of Rotor Resistance on Slip
5-8.4 Influence of Reactances on Motor Performance
5-9 Wound-Rotor Motor Starting and Speed Control
5-10 Speed Control of Polyphase Induction Motors
5-10-1 Variable Frequency
5-10.2 Line-Voltage Control
5-11 Applications of Polyphase Induction Motors
5-12 Reduced-Voltage Starting
5-13 Asynchronous Generator
5-14 Single-Phase Induction Motors
5-15 Methods of Starting Single-Phase Induction Motors
5-16 Two-Revolving-Field Theory
5-16.1 Torque
5-16.2 Double-Frequency Torque
5-17 No-Load and Locked-Rotor Tests on the Single-Phase Induction Motor
5-17.1 No-Load Test
5-17.2 Locked-Rotor Test
5-17.3 Winding Resistance Test
5-18 The Capacitor Motor
5-18.1 Equivalent Circuit of the Capacitor Motor Based on the Two-Revolving-Field Theory
5-18.2 Torque
Study Questions
Problems
Bibliography
Chapter 6: Direct-Current Machines
6-1 Structural Features of Commutator Machines
6-2 Elementary Machine
6-2.1 Voltage Induced in a Full-Pitch Armature Coil
6-2.2 General EMF Equation for DC Machines
6-3 Armature Windings
6-3.1 Lap Windings
6-3.2 Wave Windings
6-4 Field Excitation
6-5 Armature Reaction—MMF and Flux Components
6-5.1 Effect of Shifting Brushes from Geometric Neutral
6-5.2 Commutating Poles or Interpoles
6-5.3 Compensating Windings
6-5.4 Ratio of Field mmf to Armature mmf
6-5.5 Demagnetization Due to Cross-Magnetizing mmf
6-6 Commutation
6-7 Voltage Buildup in Self-Excited Generators—Critical Field Resistance
6-8 Load Characteristics of Generators
6-8.1 Separately Excited Generator
6-8.2 Self-Excited Shunt Generator
6-8.3 Series Generator
6-8.4 Compound Generator
6-9 Analysis of Steady-State Generator Performance
6-9.1 Self-Excited Shunt Generator
6-9.2 Effect of Speed on Shunt Generator Performance
6-9.3 Series Generator Graphical Analysis
6-9.4 Compound Generator
6-10 Armature Characteristic or Field-Compounding Curve
6-11 Compounding a Generator
6-12 Efficiency and Losses
6-13 Motor Torque
6-14 Speed-Torque Characteristics
6-14.1 Shunt Motor
6-14.2 Series Motor
6-14.3 Compound Motor
6-15 Steady-State Characteristics of the Shunt Motor
6-16 Steady-State Performance Characteristics of the Series Motor
6-17 Compound-Motor Steady-State Performance Characteristics
6-18 Motor Starting
6-19 Dynamic and Regenerative Braking of Motors
6-20 Dynamic Behavior of DC Machines
6-21 Basic Motor Equations
6-22 Linearization for Small-Signal Response
6-23 Phasor Relationships for Small Oscillations
6-24 Variable Armature Voltage, Constant Field Current
6-25 The Separately Excited DC Motor as a Capacitor
6-26 The Separately Excited DC Generator
6-27 Transfer Functions for the Separately Excited Generator
6-28 Control of Output Voltage
6-29 The Ward-Leonard System
6-30 Solid-State Controls for DC Machines
6-31 Basic Similarities in Induction Machines, Synchronous Machines, and DC Machines
6-32 Electromechanical Machines and Device Ratings
Voltage
Current
Speed
Frequency
Power
Temperature Rise
Volt-Amperes
Service Factor
Efficiency Index
Other Ratings
6-33 Energy Management and Economic Considerations in Motor Selection
6-33.1 Power Factor vs. Efficiency
6-33.2 Calculating Annual Savings
6-33.3 Higher-Efficiency Payback
6-33.4 Time Value of Money, Present Worth, and Life Cycle
6-33.5 Other Considerations
Study Questions
Problems
Bibliography
Chapter 7: System Applications of Synchronous Machines
7-1 Synchronous Generator Supplying an Isolated System
7-2 Parallel Operation of Synchronous Generators
7-2.1 Requirements for Connecting Synchronous Generators in Parallel
7-2.2 Loading a Synchronous Generator
7-2.3 Equal Real-Power Loads and Equal Reactive-Power Loads
7-2.4 Loci for Generated Voltage for Constant Terminal Voltage and Constant Frequency
7-2.5 Locus of Generated Voltage for Constant Real Power and Variable Excitation
7-2.6 Locus of Generated Voltage for Constant Excitation and Variable Real Power
7-3 RMS Current on Three-Phase Short Circuit
7-4 Salient-Pole Generator—General Relationships
7-4.1 Inductances of Salient-Pole Machines
7-4.2 d-Axis, q-Axis, and Zero-Sequence Quantities, Currents in Damper Circuits Negligible
7-5 Instantaneous Three-Phase Short-Circuit Current
Before Short Circuit
After Short Circuit
7-5.1 Subtransient Reactance
7-6 Time Constants
7-6.1 Direct-Axis Open-Circuit Time Constant, T'do
7-6.2 Direct-Axis Short-Circuit Transient Time Constant, T'd
7-6.3 Direct-Axis Short-Circuit Subtransient Time Constant, T''d
7-6.4 Armature Short-Circuit Time Constant, Ta
7-7 Three-Phase Short Circuit from Loaded Conditions
7-8 Transient Stability
7-8.1 Equal-Area Criterion
7-8.2 Transient Stability Limit
7-9 Swing Curves
7-9.1 The Swing Equation
7-9.2 Swing Curves
7-10 Dynamic Stability
7-10.1 Dual Excitation
Study Questions
Problems
Bibliography
Chapter 8: Special Machines
8-1 Reluctance Motors
8-1.2 Polyphase Reluctance Motors
8-2 Hysteresis Motor
8-3 Inductor Alternator
8-3.1 Homopolar Type
8-3.2 Heteropolar Type
8-4 Step Motors
8-4.1 Synchronous Inductor-Motor Operation
8-4.2 Stepper Operation
8-4.3 Bifilar Windings
8-5 Ceramic Permanent-Magnet Motors
8-5.1 Motor Characteristics
8-5.2 Applications
8-6 AC Commutator Motors
8-6.1 Single-Phase Series Motor
8-6.2 Universal Motors
8-6.3 Repulsion Motor
8-7 Control Motors
8-7.1 AC Tachometer
8-7.2 Two-Phase Control Motors
8-8 Self-Synchronous Devices
8-8.1 Three-Phase Selsyns
8-8.2 Single-Phase Selsyns
8-8.3 Synchro Control Transformers
8-9 Acyclic Machines
8-9.1 Acyclic Generators
8-9.2 Linear Acyclic Machines—Conduction Pumps
8-9.3 Induction Pumps
8-10 Magnetohydrodynamic Generators
8-10.1 Hall Effect
8-10.2 MHD Steam Power Plants
8-10.3 AC MHD
Study Questions
Problems
Bibliography
Chapter 9: Direct Conversion to Electrical Energy
9-1 Fuel Cells
9-2 Thermoelectrics
9-2.1 Maximum Output
9-2.2 Figure of Merit
9-2.3 Maximum Efficiency
9-3 Thermionic Converter
9-3.1 Work Function and Richardson’s Equation
9-3.2 Space Charge
9-3.3 Efficiency
9-3.4 Maximum Output
9-3.5 Applications
9-4 Photovoltaic Generator
9-4.1 Photons
9-4.2 Solar Energy
Study Questions
Bibliography
APPENDIX A: Laplace Transformation
A-1 The Laplace Transformation
A-2 Transforms of Simple Functions
A-2.1 Initial- and Final-Value Theorems
Initial-Value Theorem
Final-Value Theorem
APPENDIX B: Constants and Conversion Factors
APPENDIX C: Metadyne, Amplidyne, and Rotary Regulators
C-1 Equations for the Metadyne
C-1.1 Equations for the Amplidyne
C-2 The Amplidyne
C-2.1 Steady-State Performance
C-3 The Rototrol and the Regulex
C-3.1 Constant Motor Speed Control
Index