Wetzel Engineering, Inc., WEI) proposes research and development to engineer the AutoBlade -- An Autonomous Control and Actuation System for On-Blade Flow Control for Load Alleviation for Wind Turbines. This technology serves as an aggressive alternative to current active and passive methods of load alleviation by a) eliminating the majority of the sensor and actuation lag that plagues current methods of active load alleviation, and b) tailoring the aerodynamic response to the load-inducing gusts. The proposed solution combines several technologies: Flow field and aerodynamic measurement devices that allow for real-time sensing of gusts and direction change along the span of the blade; Autonomous on-board blade control systems that respond to rapid changes in flow fields i.e. gusts or extreme direction change); and State-of-the-art flow-control actuation mechanisms that do not add a level of complexity that is inhibitive of low-cost manufacturing and in-field maintenance highly reliable, compact, and minimal weight). The objectives of the presently proposed applied research project are: Promote synergy with existing development programs that are integral to the proposed approach, minimizing risk associated with product commercialization. Bench test a select few measurement devices, such as pressure measurement and inflow measurement devices, for accuracy, reliability, and ease of integration. Bench test a select few actuation devices, such as piezoelectric actuators with deflection amplification by way of post-buckled precompressed composite laminates or pressure-induced control system morphing. Both of these proposed technologies have been exhaustively bench tested in previous settings by members of the team and their associates and colleagues. Bench testing will be focused specifically on applicability to the load alleviation mechanisms specific to this FOA. Engineering analyses of system integration and design of control systems. Phase 1 will focus primarily on vetting the proposed technologies and their integration potential, with a finite level of engineering analyses of the system integration and design of control systems. Phase 2 will focus further on engineering these systems into the component-based space frame blade design for implementation and commercialization of the product. This technology builds on work that is already well underway at Wetzel Engineering, with support from USDOE through another Phase 2 SBIR grant, to develop wind turbine blades built around a component-based space frame construction. The flow field sensor and active flow control actuation technology will be much more easily incorporated into the space frame blade than in to a conventional molded fiberglass blade, and so the two technologies are highly complementary. Based on our experience with loads simulations and measurements of operating wind turbines, we anticipate that adopting the AutoBlade capable of responding rapidly to transient inflow conditions could reduce extreme loads and fatigue by an additional 30% over the current state-of-the-art low-loads passive designs with the most sophisticated active pitch control systems. A 30% reduction in loads would enable further growth of rotor size, enabling a 20-25% increase in energy capture at low-wind sites. This could translate into a similar 25% reduction in the cost of energy from wind.
