Distributed On-Blade Control for Enhanced Wind Turbine Performance

Wind turbines must improve both overall efficiency and reliability if they are to compete successfully with alternate energy sources on a cost-per-kilowatt-hour basis. High efficiency operation typically requires some form of adaptation of the turbine to variable wind speed conditions, while enhanced reliability can be realized through improvements in the turbine rotor and support structure fatigue life. Both issues may be addressed through a novel application of "smart" materials that provide on-blade aerodynamic control to wind turbine rotor systems. Actuators based Shape Memory Alloy (SMA) materials could allow the direct control of both overall turbine performance and the reduction of impulsive and fatigue-life-limiting oscillatory loads. This project will evaluate the effectiveness and feasibility of this new design and control strategy for application to wind turbine rotor systems. The approach will combine advanced rotor aeroelastic performance prediction tools with experience in SMA-based aerospace actuator development. Phase I will combine benchtop and wind tunnel testing (of both trailing edge camber control devices and deployable vortex generators) with sophisticated aeromechanics performance-prediction tools, resulting in a pre-prototype system concept suitable for continued development in Phase II. Commercial Applications and other Benefits as described by the awardee: The actuator and adaptive control system technology could be used for new turbine designs and also be applied to retrofit existing wind energy systems for improved performance and structural life. The net effect of their use would reduce the operating costs of wind turbines, thereby improving their power conversion capability and enhancing their power quality.