Integration of Distributed Generation in the Power System

MATH H.J. BOLLEN, PhD, is Senior Specialist with STRI AB, Gothenburg, Sweden; Professor in Electric Power Engineering at Luleå University of Technology, Skellefteå, Sweden; and a technical expert with the Energy Markets Inspectorate in Eskilstuna, Sweden. He is a Fellow of the IEEE.FAINAN HASSAN, PhD, is with the Alstom Grid (previously Areva T&D), Research & Technology Centre, Stafford, United Kingdom. A member of the IEEE, she has also worked as a seniorengineer for STRI AB, Gothenburg, Sweden.

• PREFACE xi ACKNOWLEDGMENTS xiiiCHAPTER 1 INTRODUCTION 1CHAPTER 2 SOURCES OF ENERGY 62.1 Wind Power 72.1.1 Status 72.1.2 Properties 72.1.3 Variations in Wind Speed 82.1.4 Variations in Production Capacity 102.1.5 The Weibull Distribution of Wind Speed 202.1.6 Power Distribution as a Function of the Wind Speed 222.1.7 Distribution of the Power Production 262.1.8 Expected Energy Production 292.2 Solar Power 302.2.1 Status 302.2.2 Properties 312.2.3 Space Requirements 322.2.4 Photovoltaics 332.2.5 Location of the Sun in the Sky 352.2.6 Cloud Coverage 392.2.7 Seasonal Variations in Production Capacity 422.2.8 Fast Variations with Time 462.3 Combined Heat-and-Power 502.3.1 Status 502.3.2 Options for Space Heating 512.3.3 Properties 522.3.4 Variation in Production with Time 532.3.5 Correlation Between CHP and Consumption 562.4 Hydropower 592.4.1 Properties of Large Hydro 602.4.2 Properties of Small Hydro 612.4.3 Variation with Time 612.5 Tidal Power 652.6 Wave Power 662.7 Geothermal Power 672.8 Thermal Power Plants 682.9 Interface with the Grid 712.9.1 Direct Machine Coupling with the Grid 722.9.2 Full Power Electronics Coupling with the Grid 732.9.3 Partial Power Electronics Coupling to the Grid 752.9.4 Distributed Power Electronics Interface 792.9.5 Impact of the Type of Interface on the Power System 802.9.6 Local Control of Distributed Generation 81CHAPTER 3 POWER SYSTEM PERFORMANCE 843.1 Impact of Distributed Generation on the Power System 843.1.1 Changes Taking Place 843.1.2 Impact of the Changes 853.1.3 How Severe Is This? 863.2 Aims of the Power System 873.3 Hosting Capacity Approach 883.4 Power Quality 913.4.1 Voltage Quality 923.4.2 Current Quality 923.4.3 Multiple Generator Tripping 933.5 Voltage Quality and Design of Distributed Generation 953.5.1 Normal Operation; Variations 963.5.2 Normal Events 963.5.3 Abnormal Events 973.6 Hosting Capacity Approach for Events 983.7 Increasing the Hosting Capacity 100CHAPTER 4 OVERLOADING AND LOSSES 1024.1 Impact of Distributed Generation 1024.2 Overloading: Radial Distribution Networks 1054.2.1 Active Power Flow Only 1054.2.2 Active and Reactive Power Flow 1084.2.3 Case Study 1: Constant Production 1094.2.4 Case Study 2: Wind Power 1104.2.5 Case Study 3: Wind Power with Induction Generators 1114.2.6 Case Study 4: Solar Power with a Hotel 1114.2.7 Minimum Consumption 1154.3 Overloading: Redundancy and Meshed Operation 1164.3.1 Redundancy in Distribution Networks 1164.3.2 Meshed Operation 1174.3.3 Redundancy in Meshed Networks 1194.4 Losses 1224.4.1 Case Study 1: Constant Production 1244.4.2 Case Study 2: Wind Power 1254.5 Increasing the Hosting Capacity 1264.5.1 Increasing the Loadability 1264.5.2 Building New Connections 1274.5.3 Intertrip Schemes 1274.5.4 Advanced Protection Schemes 1284.5.5 Energy Management Systems 1314.5.6 Power Electronics Approach 1334.5.7 Demand Control 1364.5.8 Risk-Based Approaches 1374.5.9 Prioritizing Renewable Energy 1394.5.10 Dynamic Loadability 139CHAPTER 5 VOLTAGE MAGNITUDE VARIATIONS 1415.1 Impact of Distributed Generation 1415.2 Voltage Margin and Hosting Capacity 1445.2.1 Voltage Control in Distribution Systems 1445.2.2 Voltage Rise Owing to Distributed Generation 1465.2.3 Hosting Capacity 1475.2.4 Induction Generators 1495.2.5 Measurements to Determine the Hosting Capacity 1505.2.6 Estimating the Hosting Capacity Without Measurements 1515.2.7 Choosing the Overvoltage Limit 1535.2.8 Sharing the Hosting Capacity 1565.3 Design of Distribution Feeders 1565.3.1 Basic Design Rules 1565.3.2 Terminology 1575.3.3 An Individual Generator Along a Medium-Voltage Feeder 1585.3.4 Low-Voltage Feeders 1635.3.5 Series and Shunt Compensation 1665.4 A Numerical Approach to Voltage Variations 1685.4.1 Example for Two-stage Boosting 1685.4.2 General Expressions for Two-Stage Boosting 1705.4.3 Single-Stage Boosting 1715.4.4 Microgeneration 1715.5 Tap Changers with Line-Drop Compensation 1745.5.1 Transformer with One Single Feeder 1745.5.2 Adding a Generator 1755.5.3 Calculating the Hosting Capacity 1775.5.4 Multiple Feeders from the Same Transformer 1785.6 Probabilistic Methods for Design of Distribution Feeders 1815.6.1 Need for Probabilistic Methods 1815.6.2 The System Studied 1815.6.3 Probability Density and Distribution Functions 1825.6.4 Distributions of Functions of Random Variables 1825.6.5 Mean and Standard Deviation 1835.6.6 Normal Distributions 1845.6.7 Stochastic Calculations Using Measurements 1855.6.8 Generation with Constant Production 1905.6.9 Adding Wind Power 1915.7 Statistical Approach to Hosting Capacity 1925.8 Increasing the Hosting Capacity 1975.8.1 New or Stronger Feeders 1985.8.2 Alternative Methods for Voltage Control 1995.8.3 Accurate Measurement of the Voltage Magnitude Variations 2005.8.4 Allowing Higher Overvoltages 2015.8.5 Risk-Based Approach to Overvoltages 2025.8.6 Overvoltage Protection 2035.8.7 Overvoltage Curtailment 2045.8.8 Dynamic Voltage Control 2095.8.9 Compensating the Generator’s Voltage Variations 2105.8.10 Distributed Generation with Voltage Control 2115.8.11 Coordinated Voltage Control 2185.8.12 Increasing the Minimum Load 221CHAPTER 6 POWER QUALITY DISTURBANCES 2236.1 Impact of Distributed Generation 2236.2 Fast Voltage Fluctuations 2256.2.1 Fast Fluctuations in Wind Power 2266.2.2 Fast Fluctuations in Solar Power 2286.2.3 Rapid Voltage Changes 2286.2.4 Very Short Variations 2306.2.5 Spread of Voltage Fluctuations 2336.3 Voltage Unbalance 2376.3.1 Weaker Transmission System 2376.3.2 Stronger Distribution System 2386.3.3 Large Single-Phase Generators 2406.3.4 Many Single-Phase Generators 2426.4 Low-Frequency Harmonics 2476.4.1 Wind Power: Induction Generators 2486.4.2 Generators with Power Electronics Interfaces 2506.4.3 Synchronous Generators 2516.4.4 Measurement Example 2526.4.5 Harmonic Resonances 2546.4.6 Weaker Transmission Grid 2666.4.7 Stronger Distribution Grid 2676.5 High-Frequency Distortion 2706.5.1 Emission by Individual Generators 2716.5.2 Grouping Below and Above 2 kHz 2746.5.3 Limits Below and Above 2 kHz 2756.6 Voltage Dips 2786.6.1 Synchronous Machines: Balanced Dips 2796.6.2 Synchronous Machines: Unbalanced Dips 2826.6.3 Induction Generators and Unbalanced Dips 2876.7 Increasing the Hosting Capacity 2916.7.1 Strengthening the Grid 2926.7.2 Emission Limits for Generator Units 2926.7.3 Emission Limits for Other Customers 2936.7.4 Higher Disturbance Levels 2946.7.5 Passive Harmonic Filters 2966.7.6 Power Electronics Converters 2966.7.7 Reducing the Number of Dips 2976.7.8 Broadband and High-Frequency Distortion 298CHAPTER 7 PROTECTION 2997.1 Impact of Distributed Generation 2997.2 Overcurrent Protection 3037.2.1 Upstream and Downstream Faults 3037.2.2 Hosting Capacity 3047.2.3 Fuse–Recloser Coordination 3057.2.4 Inverse-Time Overcurrent Protection 3087.3 Calculating the Fault Currents 3107.3.1 Upstream Faults 3107.3.2 Downstream Faults 3207.3.3 Induction Generators, Power Electronics, and Motor Load 3257.4 Calculating the Hosting Capacity 3267.5 Busbar Protection 3337.6 Excessive Fault Current 3347.7 Generator Protection 3367.7.1 General Requirements 3367.7.2 Insufficient Fault Current 3377.7.3 Noncontrolled Island Operation 3407.7.4 Islanding Detection 3427.7.5 Harmonic Resonance During Island Operation 3547.7.6 Protection Coordination 3577.8 Increasing the Hosting Capacity 3587.8.1 Dedicated Feeder 3597.8.2 Increased Generator Impedance 3607.8.3 Generator Tripping 3607.8.4 Time-Current Setting 3617.8.5 Adding an Additional Circuit Breaker 3627.8.6 Directional Protection 3627.8.7 Differential or Distance Protection 3637.8.8 Advanced Protection Schemes 3637.8.9 Islanding Protection 365CHAPTER 8 TRANSMISSION SYSTEM OPERATION 3678.1 Impact of Distributed Generation 3678.2 Fundamentals of Transmission System Operation 3718.2.1 Operational Reserve and (N – 1) Criterion 3728.2.2 Different Types of Reserve 3738.2.3 Automatic or Manual Secondary Control 3758.3 Frequency Control, Balancing, and Reserves 3768.3.1 The Need for Reserves 3768.3.2 Primary Control and Reserves 3778.3.3 Secondary Control and Reserves 3828.3.4 Tertiary Control and Reserves 3898.3.5 Impact of Decay in Production on Reserves 3938.4 Prediction of Production and Consumption 3988.5 Restoration after a Blackout 4038.6 Voltage Stability 4058.6.1 Short-Term Voltage Stability 4068.6.2 Long-Term Voltage Stability 4108.7 Kinetic Energy and Inertia Constant 4178.8 Frequency Stability 4228.9 Angular Stability 4258.9.1 One Area Against the Infinite Grid 4258.9.2 Impact of Distributed Generation: Before the Fault 4298.9.3 Impact of Distributed Generation: During the Fault 4308.9.4 Impact of Distributed Generation: Critical Fault-Clearing Time 4318.9.5 Impact of Distributed Generation: After the Fault 4358.9.6 Impact of Distributed Generation: Importing Area 4368.10 Fault Ride-Through 4378.10.1 Background 4378.10.2 Historical Cases 4398.10.3 Immunity Requirements 4408.10.4 Achieving Fault Ride-Through 4458.11 Storage 4478.12 HVDC and Facts 4518.13 Increasing the Hosting Capacity 4578.13.1 Alternative Scheduling of Reserves 4578.13.2 Increasing the Transfer Capacity 4588.13.3 Large-Scale Energy Storage 4588.13.4 Distributed Generation as Reserve 4598.13.5 Consumption as Reserve 4608.13.6 Requirements on Distributed Generation 4618.13.7 Reactive Power Control 4618.13.8 Probabilistic Methods 4628.13.9 Development of Standard Models for Distributed Generation 464CHAPTER 9 CONCLUSIONS 465BIBLIOGRAPHY 471INDEX 497

The author’s organization of the book is superb, and the write-up with appropriate examples is very clear.  The book will be useful to those who have good prior knowledge in power engineering including power electronics and renewable energy sources.  The book offers a very comprehensive discussion of modern power system operation with distributed generation by  renewable energy sources.  It describes sources of energy, power system performance, overloading and losses, voltage variations, power quality disturbances, faults and protection, and transmission  with distributed generation. Many examples are given with emphasis of European system. It is an excellent reference book for modern power engineers.—Dr. Bimal K. Bose, Condra Chair of Excellence/Emeritus in Power Electronics, University of Tennessee