Abstract
Abstract. This work investigates the conceptual design and the aeroservoelastic performance of land-based wind turbines whose blades can be transported on rail via controlled bending. The turbines have a nameplate power of 5 MW and a rotor diameter of 206 m, and they aim to represent the next generation of land-based machines. Three upwind designs and two downwind designs are presented, combining different design goals together with conventional glass and pultruded carbon fiber laminates in the spar caps. One of the five blade designs is segmented and serves as a benchmark to the state of the art in industry. The results show that controlled flexing requires a reduction in the flapwise stiffness of the blades, but it represents a promising pathway for increasing the size of land-based wind turbine rotors. Given the required stiffness, the rotor can be designed either downwind with standard rotor preconing and nacelle uptilt angles or upwind with higher-than-usual angles. A downwind-specific controller is also presented, featuring a cut-out wind speed reduced to 19 m s−1 and a pitch-to-stall shutdown strategy to minimize blade tip deflections toward the tower. The flexible upwind and downwind rotor designs equipped with pultruded carbon fiber spar caps are found to generate the lowest levelized cost of energy, 2.9 % and 1.3 %, respectively, less than the segmented design. The paper concludes with several recommendations for future work in the area of large flexible wind turbine rotors.
Highlights
Wind energy today is one of the most cost-competitive sources of electricity
The recent reduction in the levelized cost of energy (LCOE) for wind has been possible thanks to various factors, among which is a continuous increase in turbine size
The studies are conducted on a 5 MW platform with a rotor diameter of 206 m and a hub height of 140 m
Summary
Wind energy today is one of the most cost-competitive sources of electricity. The recent reduction in the levelized cost of energy (LCOE) for wind has been possible thanks to various factors, among which is a continuous increase in turbine size. An increasingly robust supply chain has led to fairly constant values of turbine capital costs per kilowatt, whereas larger rotors and taller towers increase annual energy production (AEP). The larger rotor-swept areas have helped to increase power generation at low wind speeds, which is especially attractive in markets that are dominated by wind energy. Electricity price is often inversely proportional to wind speed, which has pushed the technology trends toward larger rotor diameters and lower values of specific power. Low specific power allows for better predictability of power production, supporting a higher share of renewables in the energy mix (Bolinger et al, 2020)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
