Energy Storage in Power Systems

Over the last century, energy storage systems (ESSs) have continued to evolve and adapt to changing energy requirements and technological advances. Energy Storage in Power Systems describes the essential principles needed to understand the role of ESSs in modern electrical power systems, highlighting their application for the grid integration of renewable-based generation.

Key features:

• Defines the basis of electrical power systems, characterized by a high and increasing penetration of renewable-based generation.
• Describes the fundamentals, main characteristics and components of energy storage technologies, with an emphasis on electrical energy storage types.
• Contains real examples depicting the application of energy storage systems in the power system.
• Features case studies with and without solutions on modelling, simulation and optimization techniques.

Although primarily targeted at researchers and senior graduate students, Energy Storage in Power Systems is also highly useful to scientists and engineers wanting to gain an introduction to the field of energy storage and more specifically its application to modern power systems.

Foreword xi

Preface xv

1 An Introduction to Modern Power Systems 1

1.1 Introduction 1

1.2 The Smart Grid Architecture Model 3

1.3 The Electric Power System 9

1.3.1 The Structure of the Power System 9

1.3.2 The Fundamentals of Power System Analysis 9

1.4 Energy Management Systems 13

1.5 Computational Techniques 15

1.5.1 Optimization Methods and Optimal Power Flow 15

1.5.2 Security-Constrained Optimal Power Flow 16

1.6 Microgrids 16

1.7 The Regulation of the Electricity System and the Electrical Markets 17

1.8 Exercise: A Load-Flow Algorithm with Gauss–Seidel 20

2 Generating Systems Based on Renewable Power 25

2.1 Renewable Power Systems 25

2.1.1 Wind Power Systems 32

2.1.2 Solar Photovoltaic Power Systems 34

2.2 Renewable Power Generation Technologies 34

2.2.1 Renewable Power Generation Technology Based on Rotative Electrical Generators 36

2.2.2 Wind Turbine Technology 37

2.2.3 Photovoltaic Power Plants 53

2.3 Grid Code Requirements 58

2.4 Conclusions 59

3 Frequency Support Grid Code Requirements for Wind Power Plants 61

3.1 A Review of European Grid Codes Regarding Participation in Frequency Control 62

3.1.1 Nomenclature and the Definition of Power Reserves 63

3.1.2 The Deployment Sequence of Power Reserves for Frequency Control 65

3.1.3 A Detailed View on the Requirements for WPPs in the Irish Grid Code 71

3.1.4 A Detailed View on the Requirements for WPPs in the UK Grid Code 73

3.1.5 Future Trends Regarding the Provision of Primary Reserves and Synthetic Inertia by WPPs 76

3.2 Participation Methods for WPPs with Regard to Primary Frequency Control and Synthetic Inertia 79

3.2.1 Deloading Methods of Wind Turbines for Primary Frequency Control 79

3.2.2 Synthetic Inertia 87

3.3 Conclusions 91

4 Energy Storage Technologies 93

4.1 Introduction 93

4.2 The Description of the Technology 94

4.2.1 Pumped Hydroelectric Storage (PHS) 94

4.2.2 Compressed Air Energy Storage (CAES) 96

4.2.3 Conventional Batteries and Flow Batteries 97

4.2.4 The Hydrogen-Based Energy Storage System (HESS) 112

4.2.5 The Flywheel Energy Storage System (FESS) 114

4.2.6 Superconducting Magnetic Energy Storage (SMES) 116

4.2.7 The Supercapacitor Energy Storage System 120

4.2.8 Notes on Other Energy Storage Systems 125

4.3 Power Conversion Systems for Electrical Storage 129

4.3.1 Application: Electric Power Systems 129

4.3.2 Other Applications I: The Field of Electromobility 134

4.3.3 Other Applications II: Buildings 137

4.3.4 The Battery Management System (BMS) 139

4.4 Conclusions 141

5 Cost Models and Economic Analysis 143

5.1 Introduction 143

5.2 A Cost Model for Storage Technologies 145

5.2.1 The Capital Costs 145

5.2.2 Operating and Maintenance Costs 147

5.2.3 Replacement Costs 149

5.2.4 End-of-Life Costs 150

5.2.5 The Synthesis of a Cost Model 151

5.3 An Example of an Application 153

5.3.1 The Collection of Data for Evaluation of the Cost Model 154

5.3.2 Analysis of the Results 158

5.4 Conclusions 162

6 Modeling, Control, and Simulation 163

6.1 Introduction 163

6.2 Modeling of Storage Technologies: A General Approach Orientated to Simulation Objectives 164

6.3 The Modeling and Control of the Grid-Side Converter 166

6.3.1 Modeling 166

6.3.2 Control 169

6.4 The Modeling and Control of Storage-Side Converters and Storage Containers 174

6.4.1 Supercapacitors and DC–DC Converters 174

6.4.2 Secondary Batteries and DC–DC Converters 180

6.4.3 Flywheels and AC–DC Converters 190

6.5 An Example of an Application: Discharging Storage Installations Following Various Control Rules 199

6.5.1 Input Data 199

6.5.2 Discharge (Charge) Modes for Supercapacitors 201

6.5.3 Discharge (Charge) Modes for Batteries 203

6.5.4 Discharge (Charge) Modes for Flywheels 204

6.6 Conclusions 207

7 Short-Term Applications of Energy Storage Installations in the Power System 209

7.1 Introduction 209

7.2 A Description of Short-Term Applications 210

7.2.1 Fluctuation Suppression 210

7.2.2 Low-Voltage Ride-Through (LVRT) 212

7.2.3 Voltage Control Support 213

7.2.4 Oscillation Damping 214

7.2.5 Primary Frequency Control 215

7.3 An Example of Fluctuation Suppression: Flywheels for Wind Power Smoothing 217

7.3.1 The Problem of Wind Power Smoothing 217

7.3.2 Optimal Operation of the Flywheel for Wind Power Smoothing 220

7.3.3 The Design of the High-Level Energy Management Algorithm for the Flywheel 226

7.3.4 Experimental Validation 230

7.4 Conclusions 241

8 Mid- and Long-Term Applications of Energy Storage Installations in the Power System 243

8.1 Introduction 243

8.2 A Description of Mid- and Long-Term Applications 243

8.2.1 Load Following 243

8.2.2 Peak Shaving 247

8.2.3 Transmission Curtailment 248

8.2.4 Time Shifting 248

8.2.5 Unit Commitment 249

8.2.6 Seasonal Storage 250

8.3 Example: The Sizing of Batteries for Load Following in an Isolated Power System with PV Generation 250

8.3.1 Step 1: Typical Load and PV Generation Profiles 253

8.3.2 Step 2: The Voltage Level of the Battery Bank 255

8.3.3 Step 3: The Typical Daily Current Demand for the Battery Bank 257

8.3.4 Step 4: The Number of Days of Autonomy 258

8.3.5 Step 5: The Total Daily Demand for the Battery Bank 259

8.3.6 Step 6: The Capacity of the Battery 260

8.3.7 Step 7: The Number of Cells in Series 260

8.3.8 Step 8: The Number of Parallel Strings of Cells in Series 261

8.3.9 Step 9: Check the Admissible Momentary Current for the Battery Cells 261

8.3.10 Step 10: The Maximum Charge and Discharge Currents for the Battery Bank Considering PV Generation 261

8.3.11 Step 11: The Selection of Power Inverters 265

8.4 Conclusions 265

References 267

Index 285

Francisco Díaz-González, Catalonia Institute for Energy Research, Spain
Francisco Díaz-González received his degree in industrial engineering from the School of Industrial Engineering of Barcelona, Technical University of Catalonia (UPC), Barcelona, Spain, in 2009, and his Ph.D. degree in electrical engineering from the UPC in 2013. He has experience in electrical and mechanical systems modeling and simulation. Between September 2009 and June 2015 he was based with the Catalonia Institute for Energy Research, Barcelona, Spain, but since July 2015, he has been based with CITCEA-UPC research group. His current research interests include the fields linked with energy storage technologies, electrical machines, and renewable energy integration in power systems.

Andreas Sumper, Centre d'Innovació Tecnològica en Convertidors Estàtics i Accionaments, Universitat Politècnica de Catalunya, Barcelona, Spain
Andreas Sumper received his Dipl.-Ing. degree in electrical engineering from the Graz University of Technology (Austria) in 2000 and his Ph.D. degree in electrical engineering from the Universitat Politècnica de Catalunya (UPC), Barcelona, Spain, in 2008. Since 2014 he has been an Associate Professor at the UPC and he leads the Smart Grid Research at CITCEA-UPC. His research interests are renewable energy generation, microgrids and smart grids, power system studies, and energy management.

Oriol Gomis-Bellmunt,Centre d'Innovació Tecnològica en Convertidors Estàtics i Accionaments, Universitat Politècnica de Catalunya, Barcelona, Spain
Oriol Gomis-Bellmunt received his degree in industrial engineering from the School of Industrial Engineering of Barcelona, Technical University of Catalonia (UPC), Barcelona, Spain, in 2001, and his Ph.D. degree in electrical engineering from the UPC, in 2007. Since 2004, he has been with the Department of Electrical Engineering, UPC, where he is a Lecturer and participates in the CITC