Electrical Power System Essentials

Pieter Schavemaker, Managing Director of E-Bridge Consulting B.V., has worked in the energy sector for more than 25 years. Pieter has a varied experience as assistant professor at the Delft University of Technology, with a large manufacturer of power system equipment (ABB), with a Transmission System Operator (Tennet TSO), and as a consultant. Lou van der Sluis worked as researcher and test engineer at KEMA’s High-Power and High-Voltage Laboratories. From 1992 until his retirement in 2015 he held the chair of full-time Professor in Electrical Power Systems in the Electrical Sustainable Energy department of the Delft University of Technology. Prof. van der Sluis is a life-senior member of IEEE.

• Preface xiList of Abbreviations xviiList of Symbols xixAbout the Companion Websitexxi1 Introduction to Power System Analysis 11.1 Introduction 11.2 Scope of the Material 11.3 General Characteristics of Power Systems 41.3.1 AC Versus DC Systems 41.3.1.1 Shape of the Alternating Voltage 51.3.1.2 Sinusoidal Alternating Voltage 61.3.2 50 and 60 Hz Frequency 71.3.3 Balanced Three-phase Systems 91.3.3.1 Power Considerations 101.3.3.2 Rotating Magnetic Field 121.3.4 Voltage Levels 151.3.4.1 Line-to-line and Line-to-neutral Voltages 161.4 Phasors 171.4.1 Network Elements in the Phasor Domain 191.4.2 Calculations in the Phasor Domain 211.5 Equivalent Line-to-neutral Diagrams 241.6 Power in Single-phase Circuits 261.6.1 Active and Reactive Power 261.6.2 Complex Power 291.6.3 Power Factor 331.7 Power in Three-phase Circuits 341.8 Per-unit Normalization 351.9 Power System Structure 39Problems 40References 422 Generation of Electric Energy 432.1 Introduction 432.2 Thermal Power Plants 442.2.1 The Principles of Thermodynamics 452.3 Nuclear Power Plants 492.3.1 Nuclear Fission 502.3.2 Nuclear Fusion 522.4 Renewable Energy 532.4.1 Wind Energy and Wind Turbine Concepts 532.4.2 Hydropower and Pumped Storage 562.4.3 Solar Power 582.4.4 Geothermal Power 612.5 The Synchronous Machine 63Problems 70References 713 The Transmission of Electric Energy 733.1 Introduction 733.2 Transmission and Distribution Network 743.3 Network Structures 763.4 Substations 783.5 Substation Concepts 803.5.1 Single Bus System 813.5.2 Double Bus System 813.5.3 Polygon Bus System 823.5.4 One-and-a-half Circuit Breaker Concept 823.6 Protection of Transmission and Distribution Networks 833.6.1 Protective Relay Operating Principles 843.6.2 Fuses 883.6.3 Circuit Breakers 893.6.4 The Switching Arc 913.6.5 Oil Circuit Breakers 923.6.6 Air-blast Circuit Breakers 933.6.7 SF 6 Circuit Breakers 933.6.8 Vacuum Circuit Breakers 943.6.9 dc Circuit Breakers 963.6.9.1 Active commutation 973.6.9.2 Passive commutation 973.6.9.3 Hybrid technology 973.7 Surge Arresters 983.8 Transformers 993.8.1 Phase Shifts in Three-phase Transformers 1033.8.2 The Magnetizing Current 1063.8.3 Transformer Inrush Current 1083.8.4 Open-circuit and Short-circuit Tests 1093.9 Power Carriers 1103.9.1 Overhead Transmission Lines 1123.9.1.1 Insulators 1123.9.1.2 Bundled conductors 1133.9.1.3 Galloping lines 1183.9.1.4 Ground Wires or Shield Wires 1203.9.1.5 Transposition 1223.9.2 Underground Cables 1233.9.2.1 Plastic insulation 1263.9.2.2 Paper–oil insulation 1263.9.3 Gas-insulated Transmission Lines 1303.10 SF 6 Alternatives 1303.11 High-voltage Direct Current Transmission 1313.11.1 From AC to dc 134Problems 138References 1394 The Utilization of Electric Energy 1414.1 Introduction 1414.2 Types of Load 1424.2.1 Mechanical Energy 1434.2.1.1 Synchronous Motors 1444.2.1.2 Induction Motors 1454.2.2 Light 1484.2.3 Heat 1494.2.4 dc Electrical Energy 1494.2.5 Chemical Energy 1524.3 Classification of Grid Users 1524.3.1 Residential Loads 1534.3.2 Commercial and Industrial Loads 1544.3.3 Electric Railways 155Problems 157Reference 1585 Power System Control 1595.1 Introduction 1595.2 Basics of Power System Control 1615.3 Active Power and Frequency Control 1635.3.1 Primary Control 1635.3.2 Secondary Control or Load Frequency Control 1685.4 Voltage Control and Reactive Power 1705.4.1 Generator Control (Automatic Voltage Regulator) 1705.4.2 Tap-changing Transformers 1725.4.3 Reactive Power Injection 1745.4.3.1 Static Shunt Capacitors and Reactors 1745.4.3.2 Synchronous Compensators 1745.4.3.3 Static Var Compensator 1755.4.3.4 Static Synchronous Compensator 1765.5 Control of Transported Power 1785.5.1 Controlling Active Power Flows 1785.5.1.1 The Phase Shifter 1785.5.2 Controlling Reactive Power Flows 1805.5.2.1 Static Series Capacitors 1805.5.2.2 Thyristor-controlled Series Capacitor 1815.5.2.3 Static Synchronous Series Compensator 1825.5.3 Unified Power Flow Controller 1825.6 Flexible AC Transmission Systems 184Problems 185References 1876 Energy Management Systems 1896.1 Introduction 1896.2 Load Flow or Power Flow Computation 1896.2.1 Load Flow Equations 1916.2.2 General Scheme of the Newton–Raphson Load Flow 1996.2.3 Decoupled Load Flow 2036.2.4 dc Load Flow 2076.2.4.1 Active Power Equations 2076.2.4.2 Reactive Power Equations 2086.3 Optimal Power Flow 2096.4 State Estimator 2106.4.1 General Scheme of the State Estimator 2126.4.2 Bad Data Analysis 214Problems 220References 2227 Electricity Markets 2257.1 Introduction 2257.2 Electricity Market Structure 2267.2.1 Transmission and Distribution 2267.2.2 Market Architecture 2277.3 Market Clearing 2287.4 Social Welfare 2317.5 Market Coupling 2327.6 Electricity Markets: Surplus and Scarcity 2367.7 Allocation Mechanism and Zonal/Nodal Markets 2387.8 Capacity Calculation 241References 2488 Future Power Systems 2498.1 Introduction 2498.2 Renewable Energy 2508.3 Decentralized or Distributed Generation 2528.4 Power Electronics in the Power System 2558.4.1 Power-electronic Interfaces 2558.4.2 System Inertia 2568.5 Energy Storage 2578.6 Blackouts and Chaotic Phenomena 2598.6.1 Nonlinear Phenomena and Chaos 2608.6.2 Blackouts 2628.7 Wide Area Monitoring of Power Systems 2698.7.1 Wide Area Measurement Systems in the Continental European Power System 270References 272A Maxwell’s Laws 273A. 1 Introduction 273A. 2 Power Series Approach to Time-varying Fields 275A. 3 Quasi-static Field of a Parallel-plate Capacitor 276A.3. 1 Quasi-static Solution 277A.3. 2 Validity of the Quasi-static Approach 279A. 4 Quasi-static Field of a Single-turn Inductor 280A.4. 1 Quasi-static Solution 281A.4. 2 Validity of the Quasi-static Approach 282A. 5 Quasi-static Field of a Resistor 284A.5. 1 Quasi-static Solution 285A. 6 Circuit Modeling 287Reference 288B Power Transformer Model 289B. 1 Introduction 289B. 2 The Ideal Transformer 289B. 3 Magnetically Coupled Coils 292B.3. 1 Equivalence with the Ideal Transformer 294B. 4 The Nonideal Transformer 295B. 5 Three-phase Transformer 297c Synchronous Machine Model 299C. 1 Introduction 299C. 2 The Primitive Synchronous Machine 299C. 3 The Single-phase Synchronous Machine 304C. 4 The Three-phase Synchronous Machine 309C. 5 Synchronous Generator in the Power System 313d Induction Machine Model 315D.1 Introduction 315D.2 The Basic Principle of the Induction Machine 315D.2.1 A Single Rotor Winding 317D.2.2 Two Rotor Windings 318D.2.3 Rotating Rotor 320D.3 The Magnetic Field in the Air Gap 321D.3.1 Contribution of the Rotor Currents to the Air-gap Field 321D.3.2 The Flux Linkage with the Stator Windings 324D.4 A Simple Circuit Model for the Induction Machine 324D.4.1 The Stator Voltage Equation 324D.4.2 The Induction Machine as Two Magnetically Coupled Coils 325D.4.3 A Practical Model of the Induction Machine 326D.5 Induction Motor in the Power System 327E The Representation of Lines and Cables 329E.1 Introduction 329E.2 The Long Transmission Line 329E.3 The Medium-length Transmission Line 334E.4 The Short Transmission Line 334E.5 Comparison of the Three Line Models 335E.6 The Underground Cable 336F The Physics Behind the Maxwell Equations 337F. 1 Introduction 337F. 2 Ampère’s Law 337F. 3 Faraday’s Law 338F. 4 Maxwell’s Equations 339Solutions 343Further Reading 357Index 359