Author Ned Mohan has been a leader in EES education and research for decades. His three-book series on Power Electronics focuses on three essential topics in the power sequence based on applications relevant to this age of sustainable energy such as wind turbines and hybrid electric vehicles.

PREFACE xi CHAPTER 1 POWER SYSTEMS: A CHANGING LANDSCAPE 1 1.1 Nature of Power Systems 1 1.2 Changing Landscape of Power Systems and Utility Deregulation 2 1.3 Topics in Power Systems 3 References 4 Problems 5 CHAPTER 2 REVIEW OF BASIC ELECTRIC CIRCUITS AND ELECTROMAGNETIC CONCEPTS 6 2.1 Introduction [1] 6 2.2 Phasor Representation in Sinusoidal Steady State 6 2.3 Power, Reactive Power, and Power Factor 9 2.4 Three-Phase Circuits 15 2.5 Real and Reactive Power Transfer Between AC Systems 21 2.6 Apparatus Ratings, Base Values, and Per-Unit Quantities 22 2.7 Energy Efficiencies of Power System Apparatus 24 2.8 Electromagnetic Concepts 24 Reference 33 Problems 33 Appendix 2A 35 CHAPTER 3 ELECTRIC ENERGY AND THE ENVIRONMENT 39 3.1 Introduction 39 3.2 Choices and Consequences 39 3.3 Hydro Power 40 3.4 Fossil FuelBased Power Plants 41 3.5 Nuclear Power 43 3.6 Renewable Energy 45 3.7 Distributed Generation (DG) 52 3.8 Environmental Consequences and Remedial Actions 52 3.9 Resource Planning 53 References 55 Problems 55 CHAPTER 4 AC TRANSMISSION LINES AND UNDERGROUND CABLES 57 4.1 Need for Transmission Lines and Cables 57 4.2 Overhead AC Transmission Lines 57 4.3 Transposition of Transmission Line Phases 59 4.4 Transmission Lines Parameters 59 4.5 Distributed-Parameter Representation of Transmission Lines in Sinusoidal Steady State 66 4.6 Surge Impedance Zc and the Surge Impedance Loading (SII) 68 4.7 Lumped Transmission Line Models in Steady State 70 4.8 Cables [8] 72 References 73 Problems 74 Appendix 4A Long Transmission Lines 75 CHAPTER 5 POWER FLOW IN POWER SYSTEM NETWORKS 78 5.1 Introduction 78 5.2 Description of the Power System 79 5.3 Example Power System 79 5.4 Building the Admittance Matrix 80 5.5 Basic Power Flow Equations 82 5.6 Newton-Raphson Procedure 83 5.7 Solution of Power Flow Equations Using N-R Method 85 5.8 Fast Decoupled N-R Method for Power Flow 89 5.9 Sensitivity Analysis 90 5.10 Reaching the Bus Var Limit 90 5.11 Synchronized Phasor Measurements, Phasor Measurement Units (PMUs), and Wide-Area Measurement Systems 91 References 91 Problems 91 Appendix 5A Gauss-Seidel Procedure for Power Flow Calculations 92 CHAPTER 6 TRANSFORMERS IN POWER SYSTEMS 94 6.1 Introduction 94 6.2 Basic Principles of Transformer Operation 94 6.3 Simplified Transformer Model 99 6.4 Per-Unit Representation 101 6.5 Transformer Efficiencies and Leakage Reactances 103 6.6 Regulation in Transformers 104 6.7 Auto-Transformers 104 6.8 Phase-Shift Introduced by Transformers 106 6.9 Three-Winding Transformers 107 6.10 Three-Phase Transformers 108 6.11 Representing Transformers with Off-Nominal Turns Ratios, Taps, and Phase-Shift 108 References 110 Problems 110 CHAPTER 7 HIGH VOLTAGE DC (HVDC) TRANSMISSION SYSTEMS 113 7.1 Introduction 113 7.2 Power Semiconductor Devices and Their Capabilities 113 7.3 HVDC Transmission Systems 114 7.4 Current-Link HVDC Systems 115 7.5 Voltage-Link HVDC Systems 125 References 129 Problems 130 CHAPTER 8 DISTRIBUTION SYSTEM, LOADS, AND POWER QUALITY 132 8.1 Introduction 132 8.2 Distribution Systems 132 8.3 Power System Loads 133 8.4 Power Quality Considerations 137 8.5 Load Management [6,7] and Smart Grid 148 8.6 Price of Electricity [3] 149 References 149 Problems 149 CHAPTER 9 SYNCHRONOUS GENERATORS 151 9.1 Introduction 151 9.2 Structure 152 9.3 Induced EMF in the Stator Windings 154 9.4 Power Output, Stability, and the Loss of Synchronism 159 9.5 Field Excitation Control to Adjust Reactive Power 160 9.6 Field Exciters for Automatic Voltage Regulation (AVR) 162 9.7 Synchronous, Transient, and Subtransient Reactances 162 References 164 Problems 165 CHAPTER 10 VOLTAGE REGULATION AND STABILITY IN POWER SYSTEMS 166 10.1 Introduction 166 10.2 Radial System as an Example 166 10.3 Voltage Collapse 169 10.4 Prevention of Voltage Instability 170 References 176 Problems 176 CHAPTER 11 TRANSIENT AND DYNAMIC STABILITY OF POWER SYSTEMS 178 11.1 Introduction 178 11.2 Principle of Transient Stability 178 11.3 Transient Stability Evaluation in Large Systems 186 11.4 Dynamic Stability 187 References 188 Problems 188 Appendix 11A Inertia, Torque and Acceleration in Rotating Systems 188 CHAPTER 12 CONTROL OF INTERCONNECTED POWER SYSTEM AND ECONOMIC DISPATCH 192 12.1 Control Objectives 192 12.2 Voltage Control by Controlling Excitation and the Reactive Power 193 12.3 Automatic Generation Control (AGC) 194 12.4 Economic Dispatch and Optimum Power Flow 201 References 206 Problems 206 CHAPTER 13 TRANSMISSION LINE FAULTS, RELAYING, AND CIRCUIT BREAKERS 208 13.1 Causes of Transmission Line Faults 208 13.2 Symmetrical Components for Fault Analysis 209 13.3 Types of Faults 211 13.4 System Impedances for Fault Calculations 215 13.5 Calculation of Fault Currents in Large Networks 218 13.6 Protection against Short-Circuit Faults 219 References 227 Problems 227 CHAPTER 14 TRANSIENT OVERVOLTAGES, SURGE PROTECTION, AND INSULATION COORDINATION 229 14.1 Introduction 229 14.2 Causes of Overvoltages 229 14.3 Transmission Line Characteristics and Representation 230 14.4 Insulation to Withstand Overvoltages 233 14.5 Surge Arresters and Insulation Coordination 234 References 235 Problems 235