Renewable energy in power systems

✍ Scribed by Leon Freris, David Infield

• Publisher: John Wiley & Sons
• Year: 2008
• Tongue: English
• Leaves: 302
• Category: Library

✦ Synopsis

Renewable Energy (RE) sources differ from conventional sources in that, generally they cannot be scheduled, they are much smaller than conventional power stations and are often connected to the electricity distribution system rather than the transmission system.  The integration of such time variable ‘distributed’ or ‘embedded’ sources into electricity networks requires special consideration. 

This new book addresses these special issues and covers the following:

• The characteristics of conventional and RE generators with particular reference to the variable nature of RE from wind, solar, small hydro and marine sources over time scales ranging from seconds to months
• The power balance and frequency stability in a network with increasing inputs from variable sources and the technical and economic implications of increased penetration from such sources  with special reference to demand side management
• The conversion of energy into electricity from RE sources and the type and characteristics of generators used
• The requirement to condition the power from RE sources and the type and mode of operation of the power electronic converters used to interface such generators to the grid
• The flow of power over networks supplied from conventional plus RE sources with particular reference to voltage control and protection
• The economics and trading of ‘green’ electricity in national and international deregulated markets
• The expected developments in RE technology and the future shape of power systems where the penetration from RE sources is large and where substantial operational and control benefits will be   derived from extensive use of power electronic interfaces and controllers

The text is designed to be intelligible to readers who have little previous knowledge of electrical engineering. The more analytical electrical aspects are relegated to an Appendix for readers who wish to gain a more in depth  understanding. The book’s flexible structure makes its accessible to the general engineer or scientists but also caters for readers with a non-scientific background. Economists, planners and environmental specialists will find parts of the book informative. 

✦ Table of Contents

Renewable Energy in Power Systems......Page 1
Contents......Page 7
Foreword......Page 13
Preface......Page 15
Acknowledgements......Page 17
1.1.2 World Energy Consumption......Page 19
1.1.3 Finite Resources......Page 20
1.2.1 The Problem......Page 21
1.2.2 The Science......Page 23
1.2.3 The Kyoto Protocol......Page 24
1.2.4 The Stern Report......Page 25
1.2.5 Efficient Energy Use......Page 26
1.2.6 The Electricity Sector......Page 28
1.3.1 Conversion from other Energy Forms – the Importance of Efficiency......Page 29
1.3.2 The Nuclear Path......Page 30
1.3.4 Renewables......Page 31
1.4.1 Structure of the Electrical Power System......Page 34
1.4.2 Integrating Renewables into Power Systems......Page 36
1.4.4 RE Penetration......Page 37
References......Page 38
2.1 Introduction......Page 39
2.2 Conventional Sources: Coal, Gas and Nuclear......Page 40
2.3 Hydroelectric Power......Page 41
2.3.1 Large Hydro......Page 42
2.3.2 Small Hydro......Page 43
2.4.1 The Resource......Page 45
2.4.2 Wind Variability......Page 46
2.4.3 Wind Turbines......Page 48
2.4.4 Power Variability......Page 51
2.5.1 The Resource......Page 54
2.5.2 The Technology......Page 55
2.5.3 Photovoltaic Systems......Page 56
2.5.4 Solar Thermal Electric Systems......Page 58
2.6.1 The Resource......Page 60
2.6.3 Tidal Barrages......Page 61
2.6.4 Operational Strategies......Page 62
2.6.5 Tidal Current Schemes......Page 63
2.7.1 The Resource......Page 65
2.7.2 The Technology......Page 66
2.7.3 Variability......Page 67
2.8.1 The Resource......Page 68
2.8.2 Resource Sustainability......Page 69
2.9 Summary of Power Generation Characteristics......Page 70
References......Page 71
3.1.1 The Power Balance Issue......Page 73
3.2.1 Demand Curves......Page 74
3.2.2 Aggregation......Page 75
3.2.3 Demand - side Management – Deferrable Loads......Page 76
3.3.1 Power Conversion Chain......Page 77
3.3.2 The Governor......Page 78
3.3.3 Parallel Operation of Two Generators......Page 79
3.3.4 Multigenerator System......Page 80
3.3.5 The Steady State Power – Frequency Relationship......Page 81
3.4.1 Demand Matching......Page 82
3.4.2 Demand Forecasting......Page 83
3.4.3 Frequency Limits......Page 85
3.4.5 Frequency Control at Different Timescales......Page 86
3.4.6 Meeting Demand and Ensuring Reliability......Page 88
3.4.7 Capacity Factor and Capacity Credit......Page 89
3.5.1 Introduction......Page 90
3.5.2 Aggregation of Sources......Page 91
3.5.4 Impact on Balancing......Page 94
3.5.6 Discarded/Curtailed Energy......Page 97
3.5.7 Overall Penalties Due to Increasing Penetration......Page 98
3.5.10 Limits of Penetration from Nondispatchable Sources......Page 99
3.6.1 Wind power......Page 102
3.6.2 Biofuels......Page 103
3.7.1 Background......Page 104
3.7.2 A Modelling Example......Page 107
3.8.2 Storage Devices......Page 109
3.8.3 Dynamic Demand Control......Page 111
References......Page 112
Other Useful Reading......Page 113
4.1 The Conversion of Renewable Energy into Electrical Form......Page 115
4.2.1 Construction and Mode of Operation......Page 116
4.2.2 The Rotating Magnetic Field......Page 119
4.2.3 Synchronous Generator Operation when Grid - Connected......Page 121
4.2.4 The Synchronous Generator Equivalent Circuit......Page 122
4.2.5 Power Transfer Equations......Page 123
4.2.6 Three - phase Equations......Page 124
4.2.7 Four - Quadrant Operation......Page 125
4.3.1 Transformer Basics......Page 126
4.3.2 The Transformer Equivalent Circuit......Page 128
4.4.1 Construction and Properties......Page 130
4.4.2 The Induction Machine Equivalent Circuit......Page 132
4.4.3 The Induction Machine Efficiency......Page 134
4.4.4 The Induction Machine Speed – Torque Characteristic......Page 135
4.4.5 Induction Generator Reactive Power......Page 138
4.5.1 Introduction......Page 139
4.5.2 Power Semiconductor Devices......Page 140
4.5.3 Diode Bridge Rectifier......Page 142
4.5.5 The Thyristor Bridge Converter......Page 144
4.5.6 The Transistor Bridge......Page 146
4.5.8 DC – DC Converters......Page 151
4.6.1 Applications to PV Systems......Page 152
4.6.2 Applications to Wind Power......Page 155
References......Page 165
5.2 The Transmission System......Page 167
5.2.1 Single - phase Representation......Page 169
5.2.2 Transmission and Distribution Systems......Page 170
5.3 Voltage Control......Page 171
5.4.2 Single - phase Equivalent Circuit......Page 174
5.4.3 Voltage Drop Calculation......Page 175
5.4.4 Simplifications and Conclusions......Page 176
5.5.1 Reactive Power Compensation Equipment......Page 178
5.6.1 Uses of Load Flow......Page 181
5.6.2 A Particular Case......Page 182
5.6.4 Load/Generation Data......Page 183
5.6.5 The Load Flow Calculations......Page 185
5.6.7 Unbalanced Load Flow......Page 186
5.7.1 Short - circuit Fault Currents......Page 187
5.7.3 Fault Currents in General......Page 188
5.7.5 Thévenin Equivalent Circuit......Page 189
5.8 Time Varying and Dynamic Simulations......Page 190
References......Page 191
6.1.1 Introduction......Page 193
6.1.3 Connection Voltage......Page 194
6.2.1 Steady State Voltage Rise......Page 195
6.2.2 Automatic Voltage Control – Tap Changers......Page 196
6.2.3 Active and Reactive Power from Renewable Energy Generators......Page 197
6.2.4 Example Load Flow......Page 198
6.3.1 Overhead Lines and Cables......Page 201
6.4.1 Flicker, Voltage Steps and Dips......Page 202
6.4.2 Harmonics/Distortion......Page 203
6.4.4 Power Quality......Page 204
6.4.7 Fault Level Increase......Page 205
6.5.1 Introduction......Page 206
6.5.2 Loss - of - mains Protection for Rotating Machines......Page 207
6.6 Fault Ride - through......Page 208
6.7 Generator and Converter Characteristics......Page 210
References......Page 211
7.2.1 Capital and Running Costs of Renewable and Conventional Generation Plant......Page 213
7.2.2 Total Generation Costs......Page 215
7.3.1 Variety of Generators in a Power System......Page 216
7.3.2 Optimum Economic Dispatch......Page 218
7.3.3 Equal Incremental Cost Dispatch......Page 219
7.3.4 OED with Several Units and Generation Limits......Page 221
7.3.5 Costs on a Level Playing Field......Page 222
7.4.2 Types of External Cost......Page 223
7.4.3 The Kyoto Agreements......Page 224
7.4.4 Costing Pollution......Page 225
7.4.5 Pricing Pollution......Page 226
7.5.1 Value of Energy at Various Points of the Network......Page 227
7.5.2 A Cash - flow Analysis......Page 228
7.5.3 Value of Embedded Generation – Regional and Local Issues......Page 230
7.5.4 Capacity Credit......Page 231
7.6.1 Introduction......Page 233
7.6.2 Feed - in Law......Page 234
7.6.4 Carbon Tax......Page 235
7.7.2 The UK Electricity Supply Industry......Page 236
7.7.3 Competitive Wholesale Markets in Other Countries......Page 241
7.7.4 The Value of Renewable Energy in a Competitive Wholesale Market......Page 244
References......Page 247
8.1 Introduction......Page 249
8.2.1 Large Wind Turbines......Page 250
8.2.2 Offshore Wind Farm Development......Page 251
8.2.3 Building Integrated Wind Turbines......Page 256
8.3.1 PV Technology Development......Page 258
8.3.2 Solar Thermal Electric Systems......Page 259
8.4 The Future of Biofuels......Page 260
8.5 The Future of Hydro and Marine Power......Page 261
8.6.1 Distribution Network Evolution......Page 262
8.6.2 Active Networks......Page 263
8.6.4 Options to Resolve Technical Difficulties......Page 264
8.7 Conclusions......Page 267
References......Page 268
A.2 Generators and Consumers of Energy......Page 271
A.4 AC Waveforms......Page 273
A.5 Response of Circuit Components to AC......Page 274
A.5.1 Resistance......Page 275
A.5.2 Inductance......Page 276
A.5.3 Capacitance......Page 277
A.6 Phasors......Page 278
A.7 Phasor Addition......Page 279
A.8 Rectangular Notation......Page 281
A.9.2 Inductance......Page 283
A.9.4 Impedance......Page 284
A.10 Power in AC Circuits......Page 285
A.12 Complex Power......Page 287
A.13 Conservation of Active and Reactive Power......Page 289
A.14 Effects of Reactive Power Flow – Power Factor Correction......Page 290
A.15 Three - phase AC......Page 291
A.16 The Thévenin Equivalent Circuit......Page 293
Reference......Page 294
Index......Page 295

✦ Subjects

Топливно-энергетический комплекс;Альтернативная энергетика;