Preface
Contents
Chapter 1: Wind Energy Systems
1.1 Introduction
1.2 Developments in the Wind Generation Systems
Chapter 2: Wind Turbine Systems
2.1 Introduction
2.2 Wind Turbine Power and the Betz Limit
2.3 Wind Turbine Power Coefficient
2.3.1 Tip Speed Ratio
2.3.2 Mathematical Expression for Wind Turbine Power Coefficient
2.4 Wind Turbine Operation
2.4.1 Limited Speed Operation
2.4.2 High Speed Operation
Chapter 3: DC Wind Generation System
3.1 Overview of the Walney Offshore Wind Farm
3.2 Walney System Component Model
3.2.1 Induction Generator (IG) Model
3.2.2 VSC Model
3.2.3 Transformer Model
3.2.4 AC Cables Model
3.2.5 DC-Link Model
3.3 Walney System Analysis at Different Loads
3.3.1 Full-Load Results
3.3.2 Results for Three-Quarter, Half-, and One-Quarter Loads
3.4 DC Offshore Wind Generation System
3.4.1 Hybrid Generator (HG)
3.4.2 Gearbox
3.4.3 Voltage Control Scenarios
3.4.4 DC/DC Converter
3.4.5 Turbine Safety Considerations
3.5 DC System Analysis
3.5.1 DC Cable Calculations
3.5.2 Results for Full-, Three-Quarter, Half-, and One-Quarter Loads
3.6 Comparison Between DC System and Walney Wind Farm
3.7 Summary
Chapter 4: Hybrid Generator (HG) Concept
4.1 Electric Machines and Converters for Wind Turbines
4.1.1 Doubly Fed Induction Generators (DFIGs)
4.1.2 VSC-Coupled Induction, Synchronous, and PM Generators
4.1.3 Comparison of Generators
4.2 Hybrid Generator (HG) Concept
4.3 High-Voltage, Three-Phase Benchmark Synchronous Generator (SG)
4.3.1 General Details
4.3.2 Winding Arrangement
4.3.3 Magnetic Field Distribution and Flux-Density
4.3.4 Flux-Linkage and Back-EMF
4.3.5 Torque Calculations
4.3.6 Inductances
4.3.7 Modeling of Benchmark SG
4.4 Summary
Chapter 5: Multiphase Machine Design
5.1 Introduction
5.2 HG Design Philosophies
5.2.1 HG Design Philosophy for Limited Speed Region
5.3 Design of Three-Phase HG with 100% Wound Field (WF)
5.3.1 Generator Connected to a Passive Rectifier
5.3.2 Generator Connected to a VSC
5.4 Design of 9-Phase HG with 100% Wound Field (WF)
5.4.1 Comparison of 3-Phase and 9-Phase Machines
5.4.2 Generator Connected to a Passive Rectifier
5.5 Design of HG PM Rotor with NdFeB Surface Magnets
5.5.1 Sintered NdFeB Characteristics
5.5.2 Flux-Linkage, Back-EMF, and Torque
5.5.3 Inductances
5.6 Design of HG PM Rotor with Ferrite-Embedded Magnets
5.7 Design of HG PM Rotor with NdFeB-Embedded Magnets
5.7.1 Flux-Linkage, Back-EMF, and Torque
5.7.2 Inductances
5.8 Final HG Considerations
5.8.1 WF and PM Split Ratio
5.8.2 HG Loss Audit
5.9 Summary
Chapter 6: High Voltage Insulation Systems
6.1 Introduction
6.2 Analysis of the HV System Employing a 6.35 kV HG
6.3 HV Winding Types
6.4 Insulation Systems
6.4.1 Strand, Turn, and Groundwall Insulation
6.4.2 Semiconductive Slot and Voltage Stress Grading Insulation
6.4.3 Transposition
6.5 HG Insulation
6.6 Summary
References
References for Further Studies
Index