Syllabus For The Subject Electric Power System (Generation, Transmission an

ELECTRIC POWER SYSTEMS

CONTENTS

 

1. The Physics of Electricity_________________________________ 1

1.1 Basic Quantities _________________________________1

1.1.1 Introduction _________________________________1

1.1.2 Charge _________________________________2

1.1.3 Potential or Voltage _________________________________3

1.1.4 Ground _________________________________5

1.1.5 Conductivity _________________________________5

1.1.6 Current _________________________________6

1.2 Ohm’s law _________________________________8

1.2.1 Resistance _________________________________9

1.2.2 Conductance _________________________________10

1.2.3 Insulation _________________________________11

1.3 Circuit Fundamentals _________________________________11

1.3.1 Static Charge _________________________________11

1.3.2 Electric Circuits _________________________________12

1.3.3 Voltage Drop _________________________________13

1.3.4 Electric Shock _________________________________13

1.4 Resistive Heating _________________________________14

1.4.1 Calculating Resistive Heating _________________________________15

1.4.2 Transmission Voltage and Resistive Losses _________________________________17

1.5 Electric and Magnetic Fields _________________________________18

1.5.1 The Field as a Concept _________________________________18

1.5.2 Electric Fields _________________________________19

1.5.3 Magnetic Fields _________________________________21

1.5.4 Electromagnetic Induction _________________________________24

1.5.5 Electromagnetic Fields and Health Effects _________________________________25

1.5.6 Electromagnetic Radiation _________________________________26

2. Basic Circuit Analysis _________________________________30

2.1 Modeling Circuits _________________________________30

2.2 Series and Parallel Circuits _________________________________31

2.2.1 Resistance in Series _________________________________32

2.2.2 Resistance in Parallel _________________________________33

2.2.3 Network Reduction _________________________________35

2.2.4 Practical Aspects _________________________________36

2.3 Kirchhoff’s Laws _________________________________37

2.3.1 Kirchhoff’s Voltage Law _________________________________38

2.3.2 Kirchhoff’s Current Law _________________________________39

2.3.3 Application to Simple Circuits _________________________________40

2.3.4 The Superposition Principle _________________________________41

2.4 Magnetic Circuits _________________________________44

3. AC Power _________________________________49

3.1 Alternating Current and Voltage _________________________________49

3.1.1 Historical Notes _________________________________49

3.1.2 Mathematical Description _________________________________50

3.1.3 The rms Value _________________________________53

3.2 Reactance _________________________________55

3.2.1 Inductance _________________________________55

3.2.2 Capacitance _________________________________58

3.2.3 Impedance _________________________________64

3.2.4 Admittance _________________________________64

3.3 Power _________________________________66

3.3.1 Definition of Electric Power _________________________________66

3.3.2 Complex Power _________________________________68

3.3.3 The Significance of Reactive Power _________________________________73

3.4 Phasor Notation _________________________________75

3.4.1 Phasors as Graphics _________________________________75

3.4.2 Phasors as Exponentials _________________________________78

3.4.3 Operations with Phasors _________________________________80

4. Generators _________________________________85

4.1 The Simple Generator _________________________________86

4.2 The Synchronous Generator _________________________________92

4.2.1 Basic Components and Functioning _________________________________92

4.2.2 Other Design Aspects _________________________________97

4.3 Operational Control of Synchronous Generators _________________________________100

4.3.1 Single Generator: Real Power _________________________________100

4.3.2 Single Generator: Reactive Power _________________________________101

4.3.3 Multiple Generators: Real Power _________________________________107

4.3.4 Multiple Generators: Reactive Power _________________________________112

4.4 Operating Limits _________________________________115

4.5 The Induction Generator _________________________________118

4.5.1 General Characteristics _________________________________118

4.5.2 Electromagnetic Characteristics _________________________________120

4.6 Inverters _________________________________123

5. Loads _________________________________127

5.1 Resistive Loads _________________________________128

5.2 Motors _________________________________131

5.3 Electronic Devices _________________________________134

5.4 Load from the System Perspective _________________________________136

5.4.1 Coincident and Noncoincident Demand _________________________________137

5.4.2 Load Profiles and Load Duration Curve _________________________________138

5.5 Single- and Multiphase Connections _________________________________140

6. Transmission and Distribution _________________________________144

6.1 System Structure _________________________________144

6.1.1 Historical Notes _________________________________144

6.1.2 Structural Features _________________________________147

6.1.3 Sample Diagram _________________________________149

6.1.4 Topology _________________________________150

6.1.5 Loop Flow _________________________________153

6.1.6 Stations and Substations_________________________________ 156

6.1.7 Reconfiguring the System _________________________________158

6.2 Three-Phase Transmission _________________________________159

6.2.1 Rationale for Three Phases _________________________________160

6.2.2 Balancing Loads _________________________________163

6.2.3 Delta and Wye Connections _________________________________164

6.2.4 Per-Phase Analysis _________________________________166

6.2.5 Three-Phase Power _________________________________166

6.2.6 D.C. Transmission _________________________________167

6.3 Transformers _________________________________168

6.3.1 General Properties _________________________________168

6.3.2 Transformer Heating _________________________________170

6.3.3 Delta and Wye Transformers _________________________________172

6.4 Characteristics of Power Lines _________________________________175

6.4.1 Conductors _________________________________175

6.4.2 Towers, Insulators, and Other Components _________________________________179

6.5 Loading _________________________________182

6.5.1 Thermal Limits _________________________________182

6.5.2 Stability Limit _________________________________183

6.6 Voltage Control _________________________________184

6.7 Protection _________________________________188

6.7.1 Basics of Protection and Protective Devices _________________________________188

6.7.2 Protection Coordination _________________________________192

7. Power Flow Analysis_________________________________ 195

7.1 Introduction _________________________________195

7.2 The Power Flow Problem _________________________________197

7.2.1 Network Representation _________________________________197

7.2.2 Choice of Variables _________________________________198

7.2.3 Types of Buses _________________________________201

7.2.4 Variables for Balancing Real Power _________________________________201

7.2.5 Variables for Balancing Reactive Power _________________________________202

7.2.6 The Slack Bus _________________________________204

7.2.7 Summary of Variables _________________________________205

7.3 Example with Interpretation of Results _________________________________206

7.3.1 Six-Bus Example _________________________________206

7.3.2 Tweaking the Case _________________________________210

7.3.3 Conceptualizing Power Flow _________________________________211

7.4 Power Flow Equations and Solution Methods _________________________________214

7.4.1 Derivation of Power Flow Equations _________________________________214

7.4.2 Solution Methods _________________________________217

7.4.3 Decoupled Power Flow _________________________________224

7.5 Applications and Optimal Power Flow_________________________________ 226

8. System Performance _________________________________229

8.1 Reliability _________________________________229

8.1.1 Measures of Reliability _________________________________229

8.1.2 Valuation of Reliability _________________________________231

8.2 Security _________________________________233

8.3 Stability _________________________________234

8.3.1 The Concept of Stability _________________________________234

8.3.2 Steady-State Stability _________________________________236

8.3.3 Dynamic Stability _________________________________240

8.3.4 Voltage Stability _________________________________249

8.4 Power Quality _________________________________250

8.4.1 Voltage _________________________________251

8.4.2 Frequency _________________________________253

8.4.3 Waveform _________________________________255

9. System Operation, Management, and New Technology _________________________________259

9.1 Operation and Control on Different Time Scales _________________________________260

9.1.1 The Scale of a Cycle _________________________________261

9.1.2 The Scale of Real-Time Operation_________________________________ 262

9.1.3 The Scale of Scheduling _________________________________264

9.1.4 The Planning Scale _________________________________267

9.2 New Technology _________________________________268

9.2.1 Storage _________________________________268

9.2.2 Distributed Generation _________________________________271

9.2.3 Automation_________________________________ 278

9.2.4 FACTS _________________________________280

9.3 Human Factors _________________________________281

9.3.1 Operators and Engineers _________________________________281

9.3.2 Cognitive Representations of Power Systems _________________________________282

9.3.3 Operational Criteria _________________________________285

9.3.4 Implications for Technological Innovation _________________________________291

9.4 Implications for Restructuring _________________________________292

Appendix: Symbols, Units, Abbreviations, and Acronyms _________________________________298

Index_________________________________ 302