TY - GEN
T1 - A flexible wind turbine blade with an actively variable twist distribution to increase region 2 efficiency
T2 - ASME 2017 Dynamic Systems and Control Conference, DSCC 2017
AU - Nejadkhaki, Hamid Khakpour
AU - Hall, John F.
N1 - Publisher Copyright:
Copyright © 2017 ASME.
PY - 2017
Y1 - 2017
N2 - A method for designing and controlling a novel wind turbine blade is presented. The blade is modular, flexible, and additively manufactured. Conventional blades are monolithic and relatively stiff. The conventional method for improving aerodynamic efficiency is through generator torque control. The anisotropic nature of the additive manufacturing (AM) process has the potential to create a flexible blade with a low torsional-Tolongitudinal-stiffness ratio. This enables new design and control capabilities that could be applied to the twist angle distribution (TAD). Simulation results suggest this can increase the aerodynamic efficiency during Region 2 operation. The suggested blade design includes a rigid spar with flexible AM segments that form the surrounding shells. The stiffness of each individual segment and the actuator placement define the TAD. In practice, the degree of flexibility for each segment will be established through the design and AM processes. These variations in compliance allow the blade to conform to the desired set of TAD geometries. The proposed design process first determines the TAD that maximizes the aerodynamic efficiency in Region 2. A mechanical design algorithm subsequently locates a series of actuators and defines the stiffness ratio between the blade segments. The procedure is optimized to minimize the amount of variation between the theoretical TAD and that which is obtained in practice. The free-shape TAD is also determined in the final design step. The geometry is chosen to minimize the amount of deflection needed to shape the TAD as it changes with Region 2 wind speed. A control framework is also developed to set the TAD in relation to wind speed. A case study demonstrates the capability of the proposed method. The simulation results suggest that a TAD controlled through five actuators can achieve the full range of required motion. Moreover, the design solution can increase the efficiency at cut-in and rated speeds up to 3.8% and 3.3%, respectively.
AB - A method for designing and controlling a novel wind turbine blade is presented. The blade is modular, flexible, and additively manufactured. Conventional blades are monolithic and relatively stiff. The conventional method for improving aerodynamic efficiency is through generator torque control. The anisotropic nature of the additive manufacturing (AM) process has the potential to create a flexible blade with a low torsional-Tolongitudinal-stiffness ratio. This enables new design and control capabilities that could be applied to the twist angle distribution (TAD). Simulation results suggest this can increase the aerodynamic efficiency during Region 2 operation. The suggested blade design includes a rigid spar with flexible AM segments that form the surrounding shells. The stiffness of each individual segment and the actuator placement define the TAD. In practice, the degree of flexibility for each segment will be established through the design and AM processes. These variations in compliance allow the blade to conform to the desired set of TAD geometries. The proposed design process first determines the TAD that maximizes the aerodynamic efficiency in Region 2. A mechanical design algorithm subsequently locates a series of actuators and defines the stiffness ratio between the blade segments. The procedure is optimized to minimize the amount of variation between the theoretical TAD and that which is obtained in practice. The free-shape TAD is also determined in the final design step. The geometry is chosen to minimize the amount of deflection needed to shape the TAD as it changes with Region 2 wind speed. A control framework is also developed to set the TAD in relation to wind speed. A case study demonstrates the capability of the proposed method. The simulation results suggest that a TAD controlled through five actuators can achieve the full range of required motion. Moreover, the design solution can increase the efficiency at cut-in and rated speeds up to 3.8% and 3.3%, respectively.
KW - Aerodynamic efficiency
KW - Blade control
KW - Blade design
KW - Blade manufacturing
KW - Flexible blade
KW - Variable twist angle
UR - https://www.scopus.com/pages/publications/85036652875
U2 - 10.1115/DSCC2017-5282
DO - 10.1115/DSCC2017-5282
M3 - Conference contribution
AN - SCOPUS:85036652875
T3 - ASME 2017 Dynamic Systems and Control Conference, DSCC 2017
BT - Vibration in Mechanical Systems; Modeling and Validation; Dynamic Systems and Control Education; Vibrations and Control of Systems; Modeling and Estimation for Vehicle Safety and Integrity; Modeling and Control of IC Engines and Aftertreatment Systems;Unmanned Aerial Vehicles (UAVs) and Their Applications; Dynamics and Control of Renewable Energy Systems; Energy Harvesting; Control of Smart Buildings and Microgrids; Energy Systems
PB - American Society of Mechanical Engineers
Y2 - 11 October 2017 through 13 October 2017
ER -