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| Acknowledgements | |
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| Foreword | |
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| Preface | |
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| Introduction | |
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| Why Innovation? | |
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| The Challenge of Wind | |
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| The Specification of a Modern Wind Turbine | |
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| The Variability of the Wind | |
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| Commercial Wind Technology | |
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| Basis of Wind Technology Evaluation | |
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| Standard Design as Baseline | |
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| Basis of Technological Advantage | |
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| Security of Claimed Power Performance | |
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| Impact of Proposed Innovation | |
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| References | |
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| Design Background | |
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| Rotor Aerodynamic Theory | |
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| Introduction | |
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| Aerodynamic Lift | |
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| The Actuator Disc | |
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| Open Flow Actuator Disc | |
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| Axial Induction | |
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| Momentum | |
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| Generalised Actuator Disc Theory | |
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| The Force on a Diffuser | |
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| Generalised Actuator Disc Theory and Realistic Diffuser Design | |
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| Why a Rotor? | |
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| Basic Operation of a Rotor | |
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| Blade Element Momentum Theory | |
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| Momentum Equations | |
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| Blade Element Equations | |
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| Optimum Rotor Theory | |
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| The Power Coefficient, Cp | |
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| Thrust Coefficient | |
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| Out-of-Plane Bending Moment Coefficient | |
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| Generalised BEM | |
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| Limitations of Actuator Disc and BEM Theory | |
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| Actuator Disc Limitations | |
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| Wake Rotation and Tip Effect | |
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| Optimum Rotor Theory | |
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| Skewed Flow | |
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| Summary | |
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| References | |
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| Rotor Aerodynamic Design | |
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| Optimum Rotors and Solidity | |
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| Rotor Solidity and Ideal Variable Speed Operation | |
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| Solidity and Loads | |
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| Aerofoil Design Development | |
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| Sensitivity of Aerodynamic Performance to Planform Shape | |
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| Aerofoil Design Specification | |
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| References | |
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| Rotor Structural Interactions | |
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| Blade Design in General | |
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| Basics of Blade Structure | |
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| Simplified Cap Spar Analyses | |
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| Design for Minimum Mass with Prescribed Deflection | |
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| Design for Fatigue Strength: No Deflection Limits | |
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| The Effective t/c Ratio of Aerofoil Sections | |
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| Blade Design Studies: Example of a Parametric Analysis | |
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| Industrial Blade Technology | |
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| Design | |
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| Manufacturing | |
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| Design Development | |
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| References | |
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| Upscaling of Wind Turbine Systems | |
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| Introduction: Size and Size Limits | |
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| The 'Square-Cube' Law | |
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| Scaling Fundamentals | |
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| Similarity Rules for Wind Turbine Systems | |
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| Tip Speed | |
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| Aerodynamic Moment Scaling | |
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| Bending Section Modulus Scaling | |
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| Tension Section Scaling | |
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| Aeroelastic Stability | |
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| Self Weight Loads Scaling | |
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| Blade (Tip) Deflection Scaling | |
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| More Subtle Scaling Effects and Implications | |
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| Gearbox Scaling | |
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| Support Structure Scaling | |
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| Power/Energy Scaling | |
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| Electrical Systems Scaling | |
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| Control Systems Scaling | |
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| Scaling Summary | |
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| Analysis of Commercial Data | |
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| Blade Mass Scaling | |
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| Shaft Mass Scaling | |
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| Scaling of Nacelle Mass and Tower Top Mass | |
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| Tower Top Mass | |
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| Tower Scaling | |
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| Gearbox Scaling | |
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| Upscaling of VAWTs | |
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| Rated Tip Speed | |
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| Upscaling of Loads | |
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| Violating Similarity | |
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| Cost Models | |
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| Scaling Conclusions | |
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| References | |
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| Wind Energy Conversion Concepts | |
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| References | |
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| Drive Train Design | |
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| Introduction | |
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| Definitions | |
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| Objectives of Drive Train Innovation | |
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| Drive Train Technology Maps | |
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| Direct Drive | |
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| Hybrid Systems | |
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| Hydraulic Transmission | |
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| Efficiency of Drive Train Components | |
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| Introduction | |
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| Efficiency Over the Operational Range | |
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| Gearbox Efficiency | |
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| Generator Efficiency | |
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| Converter Efficiency | |
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| Transformer Efficiency | |
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| Fluid Coupling Efficiency | |
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| The Optimum Drive Train | |
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| Innovative Concepts for Power Take-Off | |
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| References | |
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| Offshore Wind Turbines | |
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| Design for Offshore | |
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| High Speed Rotor | |
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| Design Logic | |
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| Speed Limit | |
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| Rotor Configurations | |
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| Design Comparisons | |
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| 'Simpler' Offshore Turbines | |
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| Offshore Floating Turbine Systems | |
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| References | |
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| Technology Trends Summary | |
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| Evolution | |
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| Consensus in Blade Number and Operational Concept | |
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| Divergence in Drive Train Concepts | |
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| Future Wind Technology | |
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| Introduction | |
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| Airborne Systems | |
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| New System Concepts | |
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| References | |
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| Technology Evaluation | |
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| Cost of Energy | |
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| The Approach to Cost of Energy | |
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| Energy: The Power Curve | |
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| Energy: Efficiency, Reliability, Availability | |
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| Efficiency | |
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| Reliability | |
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| Availability | |
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| Capital Costs | |
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| Operation and Maintenance | |
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| Overall Cost Split | |
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| Scaling Impact on Cost | |
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| Impact of Loads (Site Class) | |
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| References | |
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| Evaluation Methodology | |
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| Key Evaluation Issues | |
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| Fatal Flaw Analysis | |
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| Power Performance | |
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| The Betz Limit | |
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| The Pressure Difference across a Wind Turbine | |
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| Total Energy in the Flow | |
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| Drive Train Torque | |
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| Representative Baseline | |
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| Design Loads Comparison | |
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| Evaluation Example: Optimum Rated Power of a Wind Turbine | |
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| Evaluation Example: The Carter Wind Turbine and Structural Flexibility | |
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| Evaluation Example: Concept Design Optimisation Study | |
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| References | |
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| Design Themes | |
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| Optimum Blade Number | |
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| Energy Capture Comparisons | |
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| Blade Design Issues | |
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| Operational and System Design Issues | |
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| Multi Bladed Rotors | |
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| References | |
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| Pitch versus Stall | |
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| Stall Regulation | |
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| Pitch Regulation | |
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| Fatigue Loading Issues | |
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| Power Quality and Network Demands | |
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| Grid Code Requirements and Implications for Wind Turbine Design | |
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| References | |
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| HAWT or VAWT? | |
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| Introduction | |
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| VAWT Aerodynamics | |
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| Power Performance and Energy Capture | |
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| Drive Train Torque | |
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| Niche Applications for VAWTs | |
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| Status of VAWT Design | |
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| Problems | |
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| Solutions? | |
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| References | |
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| Free Yaw | |
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| Yaw System COE Value | |
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| Yaw Dynamics | |
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| Yaw Damping | |
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| Main Power Transmission | |
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| Operational Experience of Free Yaw Wind Turbines | |
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| Summary View | |
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| References | |
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| Multi Rotor Systems | |
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| Introduction | |
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| Standardisation Benefit and Concept Developments | |
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| Operational Systems | |
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| Scaling Economics | |
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| History Overview | |
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| Aerodynamic Performance of Multi Rotor Arrays | |
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| Recent Multi Rotor Concepts | |
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| Multi Rotor Conclusions | |
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| References | |
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| Design Themes Summary | |
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| Innovative Technology Examples | |
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| Adaptable Rotor Concepts | |
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| Rotor Operational Demands | |
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| Control of Wind Turbines | |
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| Adaptable Rotors | |
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| The Coning Rotor | |
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| Concept | |
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| Coning Rotor: Outline Evaluation - Energy Capture | |
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| Coning Rotor: Outline Evaluation - Loads | |
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| Concept Overview | |
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| Variable Diameter Rotor | |
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| References | |
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| A Shrouded Rotor | |
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| References | |
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| The Gamesa G10X Drive Train | |
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| Gyroscopic Torque Transmission | |
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| References | |
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| The Norsetek Rotor Design | |
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| References | |
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| Siemens Blade Technology | |
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| Stall Induced Vibrations | |
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| References | |
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| Magnetic Gearing and Pseudo-Direct Drive | |
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| Magnetic Gearing Technology | |
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| Pseudo-Direct Drive Technology | |
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| References | |
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| Summary and Concluding Comments | |
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| Index | |