1．Introduction 1
1.1 A Perspective 1
1.2 Structure of Power Systems 10
1.3 Conventional Sources of Electric Energy 13
1.4 Renewable Energy Sources 25
1.5 Energy Storage 28
1.6 Growth of Power Systems in India 29
1.7 Energy Conservation 31
1.8 Deregulation 33
1.9 Distributed and Dispersed Generation 34
1.10 Environmental Aspects of Electric Energy Generation 35
1.11 Power System Engineers and Power System Studies 39
1.12 Use of Computers and Microprocessors 39
1.13 Problems Facing Indian Power Industry and its Choices 40
References 43
2．Inductance and Resistance of Transmission Lines 45
2.1 Introduction 45
2.2 Definition of Inductance 45
2.3 Flux Linkages of an Isolated Current-Carrying Conductor 46
2.4 Inductance of a Single-Phase Two-Wire Line 50
2.5 Conductor Types 51
2.6 Flux Linkages of one Conductor in a Group 53
2.7 Inductance of Composite Conductor Lines 54
2.8 Inductance of Three-Phase Lines 59
2.9 Double-Circuit Three-Phase Lines 66
2.10 Bundled Conductors 68
2.11 Resistance 70
2.12 Skin Effect and Proximity Effect 71
Problems 72
References 75
3．Capacitance of Transmission Lines 76
3.1 Introduction 76
3.2 Electric Field of a Long Straight Conductor 76
3.3 Potential Difference between two Conductors of a Group of Parallel Conductors 77
3.4 Capacitance of a Two-Wire Line 78
3.5 Capacitance of a Thfee-Phase Line with Equilateral Spacing 80
3.6 Capacitance of a Three-Phase Line with Unsymmetrical Spacing 81
3.7 Effect of Earth on Transmission Line Capacitance 83
3.8 Method of GMD(Modified) 91
3.9 Bundled Conductors 92
Problems 93
References 94
4．Representation of Power System Components 95
4.1 Introduction 95
4.2 Single-phase Solution of Balanced Three-phase Networks 95
4.3 One-Line Diagram and Impedance or Reactance Diagram 98
4.4 Per Unit(PU)System 99
4.5 Complex Power 105
4.6 Synchronous Machine 108
4.7 Representation of Loads 121
Problems 125
References 127
5．Characteristics and Performance of Power Transmission Lines 128
5.1 Introduction 128
5.2 Short Transmission Line 129
5.3 Medium Transmission Line 137
5.4 The Long Transmission Line—Rigorous Solution 139
5.5 Interpretation of the Long Line Equations 143
5.6 Ferranti Effect 150
5.7 Tuned Power Lines 151
5.8 The Equivalent Circuit of a Long Line 152
5.9 Power Flow through a Transmission Line 158
5.10 Methods of Voltage Control 173
Problems 180
References 183
6．Load Flow Studies 184
6.1 Introduction 184
6.2 Network Model Formulation 185
6.3 Formation of YBUS by Singular Transformation 189
6.4 Load Flow Problem 196
6.5 Gauss-Seidel Method 204
6.6 Newton-Raphson(NR)Method 213
6.7 Decoupled Load Flow Methods 222
6.8 Comparison of Load Flow Methods 228
6.9 Control of Voltage Profile 230
Problems 236
References 239
7．Optimal System Operation 242
7.1 Introduction 242
7.2 Optimal Operation of Generators on a Bus Bar 243
7.3 Optimal Unit Commitment(UC) 250
7.4 Reliability Considerations 253
7.5 Optimum Generation Scheduling 259
7.6 Optimal Load Flow Solution 270
7.7 Optimal Scheduling of Hydrothermal System 276
Problems 284
References 286
8．Automatic Generation and Voltage Control 290
8.1 Introduction 290
8.2 Load Frequency Control(Single Area Case) 291
8.3 Load Frequency Control and Economic Despatch Control 305
8.4 Two-Area Load Frequency Control 307
8.5 Optimal(Two-Area)Load Frequency Control 310
8.6 Automatic Voltage Control 318
8.7 Load Frequency Control with Generation Rate Constraints(GRCs) 320
8.8 Speed Governor Dead-Band and Its Effect on AGC 321
8.9 Digital LF Controllers 322
8.10 Decentralized Control 323
Problems 324
References 325
9．Symmetrical Fault Analysis 327
9.1 Introduction 327
9.2 Transient on a Transmission Line 328
9.3 Short Circuit of a Synchronous Machine(On No Load) 330
9.4 Short Circuit of a Loaded Synchronous Machine 339
9.5 Selection of Circuit Breakers 344
9.6 Algorithm for Short Circuit Studies 349
9.7 ZBUs Formulation 355
Problems 363
References 368
10．Symmetrical Components 369
10.1 Introduction 369
10.2 Symmetrical Component Transformation 370
10.3 Phase Shift in Star-Delta Transformers 377
10.4 Sequence Impedances of Transmission Lines 379
10.5 Sequence Impedances and Sequence Network of Power System 381
10.6 Sequence Impedances and Networks of Synchronous Machine 381
10.7 Sequence Impedances of Transmission Lines 385
10.8 Sequence Impedances and Networks of Transformers 386
10.9 Construction of Sequence Networks of a Power System 389
Problems 393
References 396
11．Unsymmetrical Fault Analysis 397
11.1 Introduction 397
11.2 Symmetrical Component Analysis of Unsymmetrical Faults 398
11.3 Single Line-To-Ground(LG)Fault 399
11.4 Line-To-Line(LL)Fault 402
11.5 Double Line-To-Ground(LLG)Fault 404
11.6 Open Conductor Faults 414
11.7 Bus Impedance Matrix Method For Analysis of Unsymmetrical Shunt Faults 416
Problems 427
References 432
12．Power System stability 433
12.1 Introduction 433
12.2 Dynamics of a Synchronous Machine 435
12.3 Power Angle Equation 440
12.4 Node Elimination Technique 444
12.5 Simple Systems 451
12.6 Steady State Stability 454
12.7 Transient Stability 459
12.8 Equal Area Criterion 461
12.9 Numerical Solution of Swing Equation 480
12.10 Multimachine Stability 487
12.11 Some Factors Affecting Transient Stability 496
Problems 506
References 508
13．Power System Security 510
13.1 Introduction 510
13.2 System State Classification 512
13.3 Security Analysis 512
13.4 Contingency Analysis 516
13.5 Sensitivity Factors 520
13.6 Power System Voltage Stability 524
References 529
14．An Introduction to State Estimation of Power Systems 531
14.1 Introduction 531
14.2 Least Squares Estimation:The Basic Solution 532
14.3 Static State Estimation of Power Systems 538
14.4 Tracking State Estimation of Power Systems 544
14.5 Some Computational Considerations 544
14.6 External System Equivalencing 545
14.7 Treatment of Bad Data 546
14.8 Network Observability and Pseudo-Measurements 549
14.9 Application of Power System State Estimation 550
Problems 552
References 553
15．Compensation in Power Systems 556
15.1 Introduction 556
15.2 Loading Capability 557
15.3 Load Compensation 557
15.4 Line Compensation 558
15.5 Series Compensation 559
15.6 Shunt Compensators 562
15.7 Comparison between STATCOM and SVC 565
15.8 Flexible AC Transmission Systems(FACTS) 566
15.9 Principle and Operation of Converters 567
15.10 Facts Controllers 569
References 574
16．Load Forecasting Technique 575
16.1 Introduction 575
16.2 Forecasting Methodology 577
16.3 Estimation of Average and Trend Terms 577
16.4 Estimation of Penodic Components 581
16.5 Estimation of ys(k):Time Series Approach 582
16.6 Estimation of Stochastic Component:Kalman Filtering Approach 583
16.7 Long-Term Load Predictions Using Econometric Models 587
16.8 Reactive Load Forecast 587
References 589
17．Voltage Stability 591
17.1 Introduction 591
17.2 Comparison of Angle and Voltage Stability 592
17.3 Reactive Power Flow and Voltage Collapse 593
17.4 Mathematical Formulation of Voltage Stability Problem 593
17.5 Voltage Stability Analysis 597
17.6 Prevention of Voltage Collapse 600
17.7 State-of-the-Art,Future Trends and Challenges 601
References 603
Appendix A：Introduction to Vector and Matrix Algebra 605
Appendix B：Generalized Circuit Constants 617
Appendix C：Triangular Factorization and Optimal Ordering 623
Appendix D：Elements of Power System Jacobian Matrix 629
Appendix E：Kuhn-Tucker Theorem 632
Appendix F：Real-time Computer Control of Power Systems 634
Appendix G：Introduction to MATLAB and SIMULINK 640
Answers to Problems 679
Index 685