Electrical Power System Essentials

Pieter Schavemaker, Principal Consultant, the Netherlands (nl.linkedin.com/in/pieterschavemaker) Lou van der Sluis, Professor emeritus Electrical Power Systems, Delft University of Technology, The Netherlands

• Preface xiList of Abbreviations xviiList of Symbols xix1 Introduction to Power System Analysis 11.1 Introduction 11.2 Scope of the Material 21.3 General Characteristics of Power Systems 51.3.1 AC versus DC Systems 5Shape of the alternating voltage 6Sinusoidal alternating voltage 71.3.2 50 and 60 Hz Frequency 91.3.3 Balanced Three-Phase Systems 10Power considerations 12Rotating magnetic field 141.3.4 Voltage Levels 17Line-to-line and line-to-neutral voltages 191.4 Phasors 201.4.1 Network Elements in the Phasor Domain 221.4.2 Calculations in the Phasor Domain 241.5 Equivalent Line-to-neutral Diagrams 281.6 Power in Single-phase Circuits 301.6.1 Active and Reactive Power 311.6.2 Complex Power 341.6.3 Power Factor 381.7 Power in Three-phase Circuits 401.8 Per-unit Normalization 411.9 Power System Structure 45Problems 47References 492 The Generation of Electric Energy 512.1 Introduction 512.2 Thermal Power Plants 532.2.1 The Principles of Thermodynamics 532.3 Nuclear Power Plants 582.3.1 Nuclear Fission 592.3.2 Nuclear Fusion 622.4 Renewable Energy 632.4.1 Wind Energy and Wind Turbine Concepts 632.4.2 Hydropower and Pumped Storage 672.4.3 Solar Power 692.4.4 Geothermal Power 712.5 The Synchronous Machine 74Problems 82References 843 The Transmission of Electric Energy 853.1 Introduction 853.2 Transmission and Distribution Network 863.3 Network Structures 893.4 Substations 913.5 Substation Concepts 933.5.1 Single Bus System 943.5.2 Double Bus System 953.5.3 Polygon Bus System 963.5.4 One-and-a-Half Circuit Breaker Concept 963.6 Protection of Transmission and Distribution Networks 973.6.1 Protective Relay Operating Principles 993.6.2 Fuses 1043.6.3 Circuit Breakers 1063.6.4 The Switching Arc 1073.6.5 Oil Circuit Breakers 1093.6.6 Air-Blast Circuit Breakers 1093.6.7 SF6 Circuit Breakers 1103.6.8 Vacuum Circuit Breakers 1123.7 Surge Arresters 1133.8 Transformers 1153.8.1 Phase Shifts in Three-Phase Transformers 1193.8.2 The Magnetizing Current 1233.8.3 Transformer Inrush Current 1263.8.4 Open Circuit and Short Circuit Tests 1273.9 Power Carriers 1293.9.1 Overhead Transmission Lines 131Insulators 131Bundled conductors 134Galloping lines 138Ground wires or shield wires 141Transposition 1443.9.2 Underground Cables 145Plastic insulation 147Paper–oil insulation 1483.9.3 Gas-Insulated Transmission Lines 1513.10 High-Voltage Direct Current Transmission 152From AC to DC 156Problems 160References 1614 The Utilization of Electric Energy 1634.1 Introduction 1634.2 Types of Load 1644.2.1 Mechanical Energy 165Synchronous motors 166Induction motors 1684.2.2 Light 1714.2.3 Heat 1734.2.4 DC Electrical Energy 1734.2.5 Chemical Energy 1754.3 Classification of Grid Users 1774.3.1 Residential Loads 1774.3.2 Commercial and Industrial Loads 1794.3.3 Electric Railways 180Problems 182Reference 1845 Power System Control 1855.1 Introduction 1855.2 Basics of Power System Control 1875.3 Active Power and Frequency Control 1905.3.1 Primary Control 1905.3.2 Secondary Control or Load Frequency Control (LFC) 1965.4 Voltage Control and Reactive Power 1985.4.1 Generator Control (AVR) 1995.4.2 Tap-Changing Transformers 2015.4.3 Reactive Power Injection 203Static shunt capacitors and reactors 203Synchronous compensators 204Static var compensator (SVC) 204Static synchronous compensator (STATCOM) 2065.5 Control of Transported Power 2075.5.1 Controlling Active Power Flows 207The phase shifter 2085.5.2 Controlling Reactive Power Flows 210Static series capacitors 211Thyristor-controlled series capacitor (TCSC) 211Static synchronous series compensator (SSSC) 2125.5.3 Unified Power Flow Controller (UPFC) 2145.6 Flexible AC Transmission Systems (FACTS) 215Problems 215References 2186 Energy Management Systems 2196.1 Introduction 2196.2 Load Flow or Power Flow Computation 2206.2.1 Load Flow Equations 2206.2.2 General Scheme of the Newton–Raphson Load Flow 2306.2.3 Decoupled Load Flow 2346.2.4 DC Load Flow 238Active power equations 239Reactive power equations 2406.3 Optimal Power Flow 2416.4 State Estimator 2426.4.1 General Scheme of the State Estimator 2456.4.2 Bad Data Analysis 2476.4.3 Statistical Analysis of the State Estimator 254Properties of the estimates 254Bad data detection 255Bad data identification 256Problems 257References 2607 Electricity Markets 2617.1 Introduction 2617.2 Electricity Market Structure 2627.2.1 Transmission and Distribution 2627.2.2 Market Architecture 2637.3 Market Clearing 2657.4 Social Welfare 2677.5 Market Coupling 2697.6 Allocation Mechanism and Zonal/Nodal Markets 274References 2778 Future Power Systems 2798.1 Introduction 2798.2 Renewable Energy 2808.3 Decentralized or Distributed Generation 2818.4 Power-Electronic Interfaces 2858.5 Energy Storage 2868.6 Blackouts and Chaotic Phenomena 2878.6.1 Nonlinear Phenomena and Chaos 2878.6.2 Blackouts 290References 298A Maxwell’s Laws 299A.1 Introduction 299A.2 Power Series Approach to Time-Varying Fields 300A.3 Quasi-static Field of a Parallel-plate Capacitor 302A.3.1 Quasi-static Solution 303A.3.2 Validity of the Quasi-static Approach 305A.4 Quasi-static Field of a Single-turn Inductor 307A.4.1 Quasi-static Solution 308A.4.2 Validity of the Quasi-static Approach 310A.5 Quasi-static Field of a Resistor 312A.5.1 Quasi-static Solution 312A.6 Circuit Modeling 315Reference 316B Power Transformer Model 317B.1 Introduction 317B.2 The Ideal Transformer 317B.3 Magnetically Coupled Coils 320B.3.1 Equivalence with the Ideal Transformer 323B.4 The Nonideal Transformer 324B.5 Three-Phase Transformer 327C Synchronous Machine Model 329C.1 Introduction 329C.2 The Primitive Synchronous Machine 329C.3 The Single-Phase Synchronous Machine 335C.4 The Three-Phase Synchronous Machine 341C.5 Synchronous Generator in the Power System 345D Induction Machine Model 349D.1 Introduction 349D.2 The Basic Principle of the Induction Machine 350D.2.1 A Single Rotor Winding 351D.2.2 Two Rotor Windings 354D.2.3 Rotating Rotor 354D.3 The Magnetic Field in the Air Gap 356D.3.1 Contribution of the Rotor Currents to the Air-Gap Field 356D.3.2 The Flux Linkage with the Stator Windings 359D.4 A Simple Circuit Model for the Induction Machine 360D.4.1 The Stator Voltage Equation 360D.4.2 The Induction Machine as Two Magnetically Coupled Coils 361D.4.3 A Practical Model of the Induction Machine 362D.5 Induction Motor in the Power System 363E The Representation of Lines and Cables 365E.1 Introduction 365E.2 The Long Transmission Line 365E.3 The Medium-Length Transmission Line 370E.4 The Short Transmission Line 371E.5 Comparison of the Three Line Models 371E.6 The Underground Cable 374Solutions 375Further Reading 391Index 393