Short description
Covers 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. This book also covers the power balance and frequency stability in a network with increasing inputs from variable sources.
Long description
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; and, the conversion of energy into electricity from RE sources and the type and characteristics of generators used.This book addresses 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; and, 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.
Review
Freris and Infield's new volume is a useful addition to the library ... .Readable and should be seriously considered as part of the basic research process for anyone. (Engari, December 2008)
Table of contents
- 1. Energy and Electricity.1.1 The World Energy Scene.1.1.1 History.1.1.3 Finite resources.1.2 The environmental impact of energy use.1.2.1 The problem.1.2.3 The Kyoto Protocol.1.2.1 Efficient energy use.1.2.6 Possible solutions and sustainability.1.3 Generating Electricity.1.4 The electrical power system.1.4.1 Structure of the electrical power system.1.4.2 Integrating renewables into power systems.1.5 References.2. Features of Conventional and Renewable Generation.2.1 Introduction.2.2 Conventional Sources: Coal, Gas and Nuclear.2.3 Hydroelectric power.2.3.1 Large hydro.2.3.2 Small hydro.2.4 Wind power.2.4.1 The Resource.2.4.3 Wind turbines.2.4.4 Power variability.2.5 PV and Solar Thermal Electricity.2.5.1 The resource.2.5.2 The technology.2.5.3 Photovoltaic Systems.2.5.4 Solar Thermal Electric Systems.2.6 Tidal power.2.6.1 The resource.2.6.2 Tidal Enhancement.2.6.3 Tidal barrages.2.6.4 Operational Strategies.2.6.5 Tidal Current Schemes.2.7 Wave power.2.7.1 The Resource.2.7.2 The technology.2.7.3 Variability.2.8 Biomass.2.8.1 Resource sustainability.2.9 Summary of power generation characteristics.2.10 Combining Sources.2.11 References.3. Power Balance/ Frequency Control.4. Electrical power generation and conditioning.4.1 The conversion of renewable energy into electrical form.4.2 The synchronous generator.4.2.1 Construction and mode of operation.4.2.2 The rotating magnetic field.4.2.3 Synchronous generator operation when grid connected.4.2.4 The synchronous generator equivalent circuit.4.2.5 Power transfer equations.4.2.6 Three phase equations.4.2.7 Four Quadrant operation.4.2.8 Power ? load angle characteristic. Stability.4.3 The transformer.4.3.1 Transformer basics.4.3.2 The transformer equivalent circuit.4.3.3 Further details on transformers.4.4 The asynchronous generator.4.4.1 Construction and properties.4.4.2 The induction machine equivalent circuit.4.4.3 The induction machine efficiency.4.4.4 The induction machine speed-torque characteristic.4.4.5 Induction Generator Reactive Power.4.4.6 Comparison Between Synchronous and Asynchronous Generators.4.5 Power electronics.4.5.1 Introduction.4.5.2 Power semiconductor devices.4.5.3 Diode bridge rectifier.4.5.4 Harmonics.4.5.5 The thyristor bridge converter.4.5.6 The transistor bridge.Basic square wave.The three-phase bridge.4.5.7 Converter internal control systems.4.5.8 DC-DC converters.Step-down DC-DC converter.Step-up DC-DC converter.4.6.1 Applications to PV systems.Basic grid-connected PV inverter.4.6.2 Applications to wind power.Fixed versus variable speed - energy capture (Reference [6]).Fixed - speed wind turbines.Two-speed wind turbines.Variable slip wind turbines.DFIG wind turbines (Reference [7]).Wind turbines with full converters.Synchronous generators in wind turbines.Gearless wind turbines.4.6 References.5. Power System Analysis.5.1 Introduction.5.2 The transmission system (Reference [1]).5.2.3 Transmission and distribution systems.5.2.4 Example networks.5.3 Voltage control.5.4 Power flow in an individual section of line.5.4.1 Electrical characteristics of lines and cables.5.4.2 Single-phase equivalent circuit.5.4.3 Voltage drop calculation.5.4.4 Simplifications and conclusions.5.5 Reactive Power Management.5.5.1 Reactive power compensation equipment.a) Tap changers and voltage regulators.5.6 Load flow and power-system simulation (References [2] and[3]).5.6.3 Network data.5.6.4 Load/generation data.5.6.5 The load flow calculations.5.6.6 Results.5.6.7 Unbalanced load-flow.5.7 Faults and protection.5.7.1 Short-circuit fault currents.5.7.2 Symmetrical 3-phase fault current.5.7.3 Fault currents in general.5.7.4 Fault level (short-circuit level) - weak grids.5.7.5 Thevenin equivalent circuit.5.8 Time-varying and dynamic simulations.5.9 Reliability Analysis.5.10 References.6.1 Distributed generation.6.1.2 Point of common coupling (PCC).6.1.3 Connection voltage.6.2 Voltage effects.6.2.1 Steady-state voltage rise.6.2.2 Automatic voltage control - tap changers.6.2.4 Example load-flow.6.3 Thermal limits.6.3.1 Overhead lines and cables.6.3.2 Transformers.6.4 Other embedded generation issues.6.4.1 Flicker, voltage steps and dips.6.4.2 Harmonics/Distortion.6.4.3 Phase voltage imbalance.6.4.3 Power quality.6.4.5 Network reinforcement.6.4.6 Network losses.6.4.7 Fault-level increase.6.5 Islanding.6.5.2 Loss-of-mains protection for rotating machines.6.5.3 Loss-of-mains protection for inverters.6.6 Fault ride-through.6.6 Generator and Converter characteristics.6.7 References.7. Power System Economics and the Electricity Market.7.1 Introduction.7.2 The Costs of Electricity Generation.7.2.1 Capital and Running Costs of Renewable and Conventional Generation Plant.7.2.2 Total Generation Costs.7.3 Economic Optimisation in Power Systems.7.3.1 Variety of generators in a power system.7.3.2 Optimum Economic Dispatch.7.3.3 Equal incremental cost dispatch.7.3.4 OED with several units and generation limits.7.6 Support Mechanisms for Renewable Energy.7.7 Electricity Trading.7.7.1 Introduction.7.7.2 The UK Electricity Supply Industry.7.7.3 Competitive Wholesale Markets in Other Countries.7.7.4 The Value of Renewable Energy in a Competitive Wholesale Market.Introduction.Case Study - The Impact on a Small Hydro Generator of an Electricity Market with Bilateral Trading and a Balancing Market.Trading Renewable Energy in an Electricity Market with Ex Post Pricing.Marketing Green Electricity.7.8 References.8. The future - towards a sustainable electricity supply system.8.1 Introduction.8.2 The future of wind power.8.2.1 Large wind turbines.8.2.2 Off-shore wind farm development.8.2.3 Building integrated wind turbines.8.3 The future of solar power.8.3.1 PV Technology Development.8.3.2 Solar thermal electric systems.8.4 The future of biofuels.8.5 The future of hydro and marine power.8.6 Distributed generation and the shape of future networks.8.6.1 Distribution network evolution.8.6.2 Active networks.8.6.3 Problems associated with Distributed Generation.8.6.4 Options to resolve technical difficulties.8.7 Conclusions.8.8 References.