Active Aerodynamic Load Control of Wind Turbine Blades.

The cost of wind-generated electricity can be reduced by mitigating fatigue loads acting on the rotor blades of wind turbines. One way to accomplish this is with active aerodynamic load control devices that supplement the load control obtainable with current full-span pitch control. Thin airfoil theory suggests that such devices will be more effective if they are located near the blade trailing edge. While considerable effort in Europe is concentrating on the capability of conventional trailing edge flaps to control these loads, our effort is concentrating on very small devices, called microtabs, that produce similar effects. This paper discusses the work we have done on microtabs, including a recent simulation that illustrates the large impact these small devices can exert on a blade. Although microtabs show promise for this application, significant challenges must be overcome before they can be demonstrated to be a viable, cost-effective technology.© 2007 ASME

[1]  Niels Troldborg,et al.  Computational Study of the Risø-B1-18 Airfoil with a Hinged Flap Providing Variable Trailing Edge Geometry , 2005 .

[2]  J. Michel,et al.  Load Control for Turbine Blades: A Non-Traditional Microtab Approach , 2002 .

[3]  Paul S. Veers,et al.  Aeroelastic tailoring in wind-turbine blade applications , 1998 .

[4]  Load Alleviation on Wind Turbine Blades Using Variable Airfoil Geometry , 2005 .

[5]  C. P. van Dam,et al.  Computational Analysis of a Microtab-Based Aerodynamic Load Control System for Rotor Blades , 2005 .

[6]  Christian Bak,et al.  Load Reduction Potential Using Airfoils with Variable Trailing Edge Geometry , 2005 .

[7]  Friedrich K Straub,et al.  Design of a servo-flap rotor for reduced control loads , 1994 .

[8]  Simon Joncas,et al.  Power Regulation and Optimization of Offshore Wind Turbines Through Trailing Edge Flap Control , 2005 .

[9]  P. G. Migliore,et al.  ENHANCED PERFORMANCE OF HAWTS USING ADAPTIVE BLADES , 1996 .

[10]  Kevin Standish,et al.  Two-Dimensional Wind Tunnel and Computational Investigation of a Microtab Modified Airfoil , 2005 .

[11]  J. Katz,et al.  Low-Speed Aerodynamics , 1991 .

[12]  Christian Bak,et al.  Potential load reduction using airfoils with variable trailing edge geometry , 2005 .

[13]  Scott D. Collins,et al.  Active Load Control for Airfoils using Microtabs , 2001 .

[14]  Paul S. Veers,et al.  AEROELASTIC BEHAVIOR OF TWIST-COUPLED HAWT BLADES , 1998 .

[15]  Gunjit Bir,et al.  The Use of Twist-Coupled Blades to Enhance the Performance of Horizontal Axis Wind Turbines , 2001 .

[16]  C. P. van Dam,et al.  Computational Investigation of Finite Width Microtabs for Aerodynamic Load Control , 2005 .

[17]  Charles P. Butterfield,et al.  Considerations for an Integrated Wind Turbine Controls Capability at the National Wind Technology Center: An Aileron Control Case Study for Power Regulation and Load Mitigation , 1996 .

[18]  Don W. Lobitz,et al.  Load mitigation with twist-coupled HAWT blades , 1999 .

[19]  Scott D. Collins,et al.  Active load control and lift enhancement using MEM translational tabs , 2000 .

[20]  Imad Abdallah.  Advanced load alleviation for wind turbines using adaptive trailing edge geometry : Sensoring techniques , 2006 .

[21]  Raymond Chow,et al.  Unsteady Computational Investigations of Deploying Load Control Microtabs , 2006 .

[22]  Patrick Moriarty,et al.  AeroDyn Theory Manual , 2005 .

[23]  Mac Gaunaa,et al.  Wind tunnel test on wind turbine airfoil with adaptive trailing edge geometry , 2007 .

[24]  Torben J. Larsen,et al.  Active load reduction using individual pitch, based on local blade flow measurements , 2005 .

[25]  Raymond Chow,et al.  Computational Investigations of Deploying Load Control Microtabs on a Wind Turbine Airfoil , 2007 .

[26]  Jason Jonkman,et al.  FAST User's Guide , 2005 .

[27]  Alan Wright,et al.  Design of Controls to Attenuate Loads in the Controls Advanced Research Turbine , 2004 .