Articles | Volume 7, issue 1
https://doi.org/10.5194/wes-7-161-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/wes-7-161-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Review article
| 
24 Jan 2022
Review article |
| 24 Jan 2022
| 24 Jan 2022
Damping identification of offshore wind turbines using operational modal analysis: a review
Aemilius A. W. van Vondelen
Delft Center for Systems and Control, Delft University of Technology, 2628CN Delft, the Netherlands
Sachin T. Navalkar
CORRESPONDING AUTHOR
Siemens Gamesa Renewable Energy, Prinses Beatrixlaan 800, 2595BN The Hague, the Netherlands
Alexandros Iliopoulos
Siemens Gamesa Renewable Energy, Prinses Beatrixlaan 800, 2595BN The Hague, the Netherlands
Daan C. van der Hoek
Delft Center for Systems and Control, Delft University of Technology, 2628CN Delft, the Netherlands
Jan-Willem van Wingerden
Delft Center for Systems and Control, Delft University of Technology, 2628CN Delft, the Netherlands
Related authors
Marion Coquelet, Maxime Lejeune, Laurent Bricteux, Aemilius A. W. van Vondelen, Jan-Willem van Wingerden, and Philippe Chatelain
Wind Energ. Sci. Discuss., https://doi.org/10.5194/wes-2024-56, https://doi.org/10.5194/wes-2024-56, 2024
Preprint under review for WES
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An extended Kalman filter is used to estimate the wind impinging on a wind turbine based on the blade bending moments and a turbine model. Using Large-Eddy Simulations, this paper verifies how robust the estimator is to the turbine control strategy, as it impacts loads and operating parameters. It is shown that including dynamics in the turbine model to account for delays between actuation and bending moments is needed to maintain the accuracy of the estimator when dynamic pitch control is used.
Marion Coquelet, Maxime Lejeune, Laurent Bricteux, Aemilius A. W. van Vondelen, Jan-Willem van Wingerden, and Philippe Chatelain
Wind Energ. Sci. Discuss., https://doi.org/10.5194/wes-2024-56, https://doi.org/10.5194/wes-2024-56, 2024
Preprint under review for WES
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An extended Kalman filter is used to estimate the wind impinging on a wind turbine based on the blade bending moments and a turbine model. Using Large-Eddy Simulations, this paper verifies how robust the estimator is to the turbine control strategy, as it impacts loads and operating parameters. It is shown that including dynamics in the turbine model to account for delays between actuation and bending moments is needed to maintain the accuracy of the estimator when dynamic pitch control is used.
Matteo Baricchio, Pieter M. O. Gebraad, and Jan-Willem van Wingerden
Wind Energ. Sci. Discuss., https://doi.org/10.5194/wes-2024-50, https://doi.org/10.5194/wes-2024-50, 2024
Preprint under review for WES
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Wake steering can be integrated within the wind farm layout optimization through a co-design approach. This study estimates the potential of this method for a wide range of realistic conditions, adopting a tailored genetic algorithm and novel geometric yaw relations. A gain in the annual energy yield between 0.3 % and 0.4 % is obtained for a 16-tubrines farm and a multi-objective implementation is used to limit the loss in case wake steering is not used during the farm operation.
Maarten J. van den Broek, Marcus Becker, Benjamin Sanderse, and Jan-Willem van Wingerden
Wind Energ. Sci., 9, 721–740, https://doi.org/10.5194/wes-9-721-2024, https://doi.org/10.5194/wes-9-721-2024, 2024
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Wind turbine wakes negatively affect wind farm performance as they impinge on downstream rotors. Wake steering reduces these losses by redirecting wakes using yaw misalignment of the upstream rotor. We develop a novel control strategy based on model predictions to implement wake steering under time-varying conditions. The controller is tested in a high-fidelity simulation environment and improves wind farm power output compared to a state-of-the-art reference controller.
Livia Brandetti, Sebastiaan Paul Mulders, Roberto Merino-Martinez, Simon Watson, and Jan-Willem van Wingerden
Wind Energ. Sci., 9, 471–493, https://doi.org/10.5194/wes-9-471-2024, https://doi.org/10.5194/wes-9-471-2024, 2024
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This research presents a multi-objective optimisation approach to balance vertical-axis wind turbine (VAWT) performance and noise, comparing the combined wind speed estimator and tip-speed ratio (WSE–TSR) tracking controller with a baseline. Psychoacoustic annoyance is used as a novel metric for human perception of wind turbine noise. Results showcase the WSE–TSR tracking controller’s potential in trading off the considered objectives, thereby fostering the deployment of VAWTs in urban areas.
Amr Hegazy, Peter Naaijen, Vincent Leroy, Félicien Bonnefoy, Yves Pérignon, and Jan-Willem van Wingerden
Wind Energ. Sci. Discuss., https://doi.org/10.5194/wes-2023-180, https://doi.org/10.5194/wes-2023-180, 2024
Revised manuscript accepted for WES
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Successful wave tank experiments were conducted to evaluate the feedforward control strategy benefits in terms of the structural loads and the power quality of the floating wind turbine components. In short, the wave feedforward control strategy is effective when it comes to alleviating the effects of the wave forces on the FOWT, whereas, wave FF control requires significant amount of actuation to minimise the platform pitch motion, which makes such a technology unfavourable for that objective.
Maarten J. van den Broek, Delphine De Tavernier, Paul Hulsman, Daan van der Hoek, Benjamin Sanderse, and Jan-Willem van Wingerden
Wind Energ. Sci., 8, 1909–1925, https://doi.org/10.5194/wes-8-1909-2023, https://doi.org/10.5194/wes-8-1909-2023, 2023
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As wind turbines produce power, they leave behind wakes of slow-moving air. We analyse three different models to predict the effects of these wakes on downstream wind turbines. The models are validated with experimental data from wind tunnel studies for steady and time-varying conditions. We demonstrate that the models are suitable for optimally controlling wind turbines to improve power production in large wind farms.
Livia Brandetti, Sebastiaan Paul Mulders, Yichao Liu, Simon Watson, and Jan-Willem van Wingerden
Wind Energ. Sci., 8, 1553–1573, https://doi.org/10.5194/wes-8-1553-2023, https://doi.org/10.5194/wes-8-1553-2023, 2023
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This research presents the additional benefits of applying an advanced combined wind speed estimator and tip-speed ratio tracking (WSE–TSR) controller compared to the baseline Kω2. Using a frequency-domain framework and an optimal calibration procedure, the WSE–TSR tracking control scheme shows a more flexible trade-off between conflicting objectives: power maximisation and load minimisation. Therefore, implementing this controller on large-scale wind turbines will facilitate their operation.
Daniel van den Berg, Delphine de Tavernier, and Jan-Willem van Wingerden
Wind Energ. Sci., 8, 849–864, https://doi.org/10.5194/wes-8-849-2023, https://doi.org/10.5194/wes-8-849-2023, 2023
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Wind turbines placed in farms interact with their wake, lowering the power production of the wind farm. This can be mitigated using so-called wake mixing techniques. This work investigates the coupling between the pulse wake mixing technique and the motion of floating wind turbines using the pulse. Frequency response experiments and time domain simulations show that extra movement is undesired and that the
optimalexcitation frequency is heavily platform dependent.
Johan Meyers, Carlo Bottasso, Katherine Dykes, Paul Fleming, Pieter Gebraad, Gregor Giebel, Tuhfe Göçmen, and Jan-Willem van Wingerden
Wind Energ. Sci., 7, 2271–2306, https://doi.org/10.5194/wes-7-2271-2022, https://doi.org/10.5194/wes-7-2271-2022, 2022
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We provide a comprehensive overview of the state of the art and the outstanding challenges in wind farm flow control, thus identifying the key research areas that could further enable commercial uptake and success. To this end, we have structured the discussion on challenges and opportunities into four main areas: (1) insight into control flow physics, (2) algorithms and AI, (3) validation and industry implementation, and (4) integrating control with system design
(co-design).
Marcus Becker, Bastian Ritter, Bart Doekemeijer, Daan van der Hoek, Ulrich Konigorski, Dries Allaerts, and Jan-Willem van Wingerden
Wind Energ. Sci., 7, 2163–2179, https://doi.org/10.5194/wes-7-2163-2022, https://doi.org/10.5194/wes-7-2163-2022, 2022
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In this paper we present a revised dynamic control-oriented wind farm model. The model can simulate turbine wake behaviour in heterogeneous and changing wind conditions at a very low computational cost. It utilizes a three-dimensional turbine wake model which also allows capturing vertical wind speed differences. The model could be used to maximise the power generation of with farms, even during events like a wind direction change. It is publicly available and open for further development.
Tuhfe Göçmen, Filippo Campagnolo, Thomas Duc, Irene Eguinoa, Søren Juhl Andersen, Vlaho Petrović, Lejla Imširović, Robert Braunbehrens, Jaime Liew, Mads Baungaard, Maarten Paul van der Laan, Guowei Qian, Maria Aparicio-Sanchez, Rubén González-Lope, Vinit V. Dighe, Marcus Becker, Maarten J. van den Broek, Jan-Willem van Wingerden, Adam Stock, Matthew Cole, Renzo Ruisi, Ervin Bossanyi, Niklas Requate, Simon Strnad, Jonas Schmidt, Lukas Vollmer, Ishaan Sood, and Johan Meyers
Wind Energ. Sci., 7, 1791–1825, https://doi.org/10.5194/wes-7-1791-2022, https://doi.org/10.5194/wes-7-1791-2022, 2022
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The FarmConners benchmark is the first of its kind to bring a wide variety of data sets, control settings, and model complexities for the (initial) assessment of wind farm flow control benefits. Here we present the first part of the benchmark results for three blind tests with large-scale rotors and 11 participating models in total, via direct power comparisons at the turbines as well as the observed or estimated power gain at the wind farm level under wake steering control strategy.
Daan van der Hoek, Joeri Frederik, Ming Huang, Fulvio Scarano, Carlos Simao Ferreira, and Jan-Willem van Wingerden
Wind Energ. Sci., 7, 1305–1320, https://doi.org/10.5194/wes-7-1305-2022, https://doi.org/10.5194/wes-7-1305-2022, 2022
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The paper presents a wind tunnel experiment where dynamic induction control was implemented on a small-scale turbine. By periodically changing the pitch angle of the blades, the low-velocity turbine wake is perturbed, and hence it recovers at a faster rate. Small particles were released in the flow and subsequently recorded with a set of high-speed cameras. This allowed us to reconstruct the flow behind the turbine and investigate the effect of dynamic induction control on the wake.
Yichao Liu, Riccardo Ferrari, and Jan-Willem van Wingerden
Wind Energ. Sci., 7, 523–537, https://doi.org/10.5194/wes-7-523-2022, https://doi.org/10.5194/wes-7-523-2022, 2022
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The objective of the paper is to develop a data-driven output-constrained individual pitch control approach, which will not only mitigate the blade loads but also reduce the pitch activities. This is achieved by only reducing the blade loads violating a user-defined bound, which leads to an economically viable load control strategy. The proposed control strategy shows promising results of load reduction in the wake-rotor overlapping and turbulent sheared wind conditions.
Unai Gutierrez Santiago, Alfredo Fernández Sisón, Henk Polinder, and Jan-Willem van Wingerden
Wind Energ. Sci., 7, 505–521, https://doi.org/10.5194/wes-7-505-2022, https://doi.org/10.5194/wes-7-505-2022, 2022
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The gearbox is one of the main contributors to the overall cost of wind energy, and it is acknowledged that we still do not fully understand its loading. The study presented in this paper develops a new alternative method to measure input rotor torque in wind turbine gearboxes, overcoming the drawbacks related to measuring on a rotating shaft. The method presented in this paper could make measuring gearbox torque more cost-effective, which would facilitate its adoption in serial wind turbines.
Alessandro Fontanella, Mees Al, Jan-Willem van Wingerden, and Marco Belloli
Wind Energ. Sci., 6, 885–901, https://doi.org/10.5194/wes-6-885-2021, https://doi.org/10.5194/wes-6-885-2021, 2021
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Floating wind is a key technology to harvest the abundant wind energy resource of deep waters. This research introduces a new way of controlling the wind turbine to better deal with the action of waves. The turbine is made aware of the incoming waves, and the information is exploited to enhance power production.
Bart M. Doekemeijer, Stefan Kern, Sivateja Maturu, Stoyan Kanev, Bastian Salbert, Johannes Schreiber, Filippo Campagnolo, Carlo L. Bottasso, Simone Schuler, Friedrich Wilts, Thomas Neumann, Giancarlo Potenza, Fabio Calabretta, Federico Fioretti, and Jan-Willem van Wingerden
Wind Energ. Sci., 6, 159–176, https://doi.org/10.5194/wes-6-159-2021, https://doi.org/10.5194/wes-6-159-2021, 2021
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This article presents the results of a field experiment investigating wake steering on an onshore wind farm. The measurements show that wake steering leads to increases in power production of up to 35 % for two-turbine interactions and up to 16 % for three-turbine interactions. However, losses in power production are seen for various regions of wind directions. The results suggest that further research is necessary before wake steering will consistently lead to energy gains in wind farms.
Joeri Alexis Frederik, Robin Weber, Stefano Cacciola, Filippo Campagnolo, Alessandro Croce, Carlo Bottasso, and Jan-Willem van Wingerden
Wind Energ. Sci., 5, 245–257, https://doi.org/10.5194/wes-5-245-2020, https://doi.org/10.5194/wes-5-245-2020, 2020
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The interaction between wind turbines in a wind farm through their wakes is a widely studied research area. Until recently, research was focused on finding constant turbine inputs that optimize the performance of the wind farm. However, recent studies have shown that time-varying, dynamic inputs might be more beneficial. In this paper, the validity of this approach is further investigated by implementing it in scaled wind tunnel experiments and assessing load effects, showing promising results.
Steffen Raach, Bart Doekemeijer, Sjoerd Boersma, Jan-Willem van Wingerden, and Po Wen Cheng
Wind Energ. Sci. Discuss., https://doi.org/10.5194/wes-2019-54, https://doi.org/10.5194/wes-2019-54, 2019
Publication in WES not foreseen
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The presented work combines two control approaches of wake redirection control, feedforward wake redirection and feedback wake redirction. In our previous investigatins the lidar-assisted feedback control was studied and the advantages and disadvantages were discussed. The optimal yaw angles for the wind turbines are precomputed, the feedback takes care of uncertainties and disturbances. The concept is demonstrated in a high fidelity simulation model.
Hector Mendez Reyes, Stoyan Kanev, Bart Doekemeijer, and Jan-Willem van Wingerden
Wind Energ. Sci., 4, 549–561, https://doi.org/10.5194/wes-4-549-2019, https://doi.org/10.5194/wes-4-549-2019, 2019
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Within wind farms, the wind turbines interact with each other through their wakes. Turbines operating in these wakes have lower power production and increased wear and tear. Wake redirection is control strategy to steer the wakes aside from downstream turbines, increasing the power yield of the farm. Models for predicting the power gain and impacts on wear exist, but they are still immature and require validation. The validation of such a model is the purpose of this paper.
Andreas Rott, Bart Doekemeijer, Janna Kristina Seifert, Jan-Willem van Wingerden, and Martin Kühn
Wind Energ. Sci., 3, 869–882, https://doi.org/10.5194/wes-3-869-2018, https://doi.org/10.5194/wes-3-869-2018, 2018
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Active wake deflection (AWD) aims to increase the power output of a wind farm by misaligning the yaw of upstream turbines. We analysed the effect of dynamic wind direction changes on AWD. The results show that AWD is very sensitive towards these dynamics. Therefore, we present a robust active wake control, which considers uncertainties and wind direction changes, increasing the overall power output of a wind farm. A side effect is a significant reduction of the yaw actuation of the turbines.
Bart M. Doekemeijer, Sjoerd Boersma, Lucy Y. Pao, Torben Knudsen, and Jan-Willem van Wingerden
Wind Energ. Sci., 3, 749–765, https://doi.org/10.5194/wes-3-749-2018, https://doi.org/10.5194/wes-3-749-2018, 2018
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Most wind farm control algorithms in the literature rely on a simplified mathematical model that requires constant calibration to the current conditions. This paper provides such an estimation algorithm for a dynamic model capturing the turbine power production and flow field at hub height. Performance was demonstrated in high-fidelity simulations for two-turbine and nine-turbine farms, accurately estimating the ambient conditions and wind field inside the farms at a low computational cost.
Sebastiaan Paul Mulders, Niels Frederik Boudewijn Diepeveen, and Jan-Willem van Wingerden
Wind Energ. Sci., 3, 615–638, https://doi.org/10.5194/wes-3-615-2018, https://doi.org/10.5194/wes-3-615-2018, 2018
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The modeling, operating strategy, and controller design for an actual in-field wind turbine with a fixed-displacement hydraulic drivetrain are presented. An analysis is given on a passive torque control strategy for below-rated operation. The turbine lacks the option to influence the system torque by a generator, so the turbine is regulated by a spear valve in the region between below- and above-rated operation. The control design is evaluated on a real-world 500 kW hydraulic wind turbine.
Sjoerd Boersma, Bart Doekemeijer, Mehdi Vali, Johan Meyers, and Jan-Willem van Wingerden
Wind Energ. Sci., 3, 75–95, https://doi.org/10.5194/wes-3-75-2018, https://doi.org/10.5194/wes-3-75-2018, 2018
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Controlling the flow within wind farms to reduce the fatigue loads and provide grid facilities such as the delivery of a demanded power is a challenging control problem due to the underlying time-varying non-linear wake dynamics. In this paper, a control-oriented dynamical wind farm model is presented and validated with high-fidelity wind farm models. In contrast to the latter models, the model presented in this work is computationally efficient and hence suitable for online wind farm control.
Edwin van Solingen, Sebastiaan Paul Mulders, and Jan-Willem van Wingerden
Wind Energ. Sci., 2, 153–173, https://doi.org/10.5194/wes-2-153-2017, https://doi.org/10.5194/wes-2-153-2017, 2017
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The aim of this paper is to show that with an automated tuning strategy, wind turbine control performance can be significantly increased. To this end, iterative feedback tuning (IFT) is applied to two different turbine controllers. The results obtained by high-fidelity simulations indicate significant performance improvements over baseline controllers. It is concluded that IFT of turbine controllers has the potential to become a valuable tool for improving wind turbine performance.
Sachin T. Navalkar, Lars O. Bernhammer, Jurij Sodja, Edwin van Solingen, Gijs A. M. van Kuik, and Jan-Willem van Wingerden
Wind Energ. Sci., 1, 205–220, https://doi.org/10.5194/wes-1-205-2016, https://doi.org/10.5194/wes-1-205-2016, 2016
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In order to reduce the cost of wind energy, it is necessary to reduce the loads that wind turbines withstand over their lifetime. The combination of blade rotation with newly designed blade shape changing actuators is demonstrated experimentally. While load reduction is achieved, the additional flexibility implies that careful control design is needed to avoid instability.
G. A. M. van Kuik, J. Peinke, R. Nijssen, D. Lekou, J. Mann, J. N. Sørensen, C. Ferreira, J. W. van Wingerden, D. Schlipf, P. Gebraad, H. Polinder, A. Abrahamsen, G. J. W. van Bussel, J. D. Sørensen, P. Tavner, C. L. Bottasso, M. Muskulus, D. Matha, H. J. Lindeboom, S. Degraer, O. Kramer, S. Lehnhoff, M. Sonnenschein, P. E. Sørensen, R. W. Künneke, P. E. Morthorst, and K. Skytte
Wind Energ. Sci., 1, 1–39, https://doi.org/10.5194/wes-1-1-2016, https://doi.org/10.5194/wes-1-1-2016, 2016
Related subject area
Offshore technology
A framework for simultaneous design of wind turbines and cable layout in offshore wind
Alignment of scanning lidars in offshore wind farms
FAST.Farm load validation for single wake situations at alpha ventus
Exploitation of the far-offshore wind energy resource by fleets of energy ships – Part 2: Updated ship design and cost of energy estimate
Revealing system variability in offshore service operations through systemic hazard analysis
Characterization of the unsteady aerodynamic response of a floating offshore wind turbine to surge motion
Characterisation of the offshore precipitation environment to help combat leading edge erosion of wind turbine blades
US East Coast synthetic aperture radar wind atlas for offshore wind energy
Brief communication: Nowcasting of precipitation for leading-edge-erosion-safe mode
Exploitation of the far-offshore wind energy resource by fleets of energy ships – Part 1: Energy ship design and performance
Analysing uncertainties in offshore wind farm power output using measure–correlate–predict methodologies
Exploitation of the far-offshore wind energy resource by fleets of energy ships. Part B. Cost of energy
Hurricane eyewall winds and structural response of wind turbines
Extending the life of wind turbine blade leading edges by reducing the tip speed during extreme precipitation events
Applications of satellite winds for the offshore wind farm site Anholt
Decoupled simulations of offshore wind turbines with reduced rotor loads and aerodynamic damping
Brief communication: Structural monitoring for lifetime extension of offshore wind monopiles: can strain measurements at one level tell us everything?
Simulation of an offshore wind farm using fluid power for centralized electricity generation
Effect of foundation modelling on the fatigue lifetime of a monopile-based offshore wind turbine
Juan-Andrés Pérez-Rúa and Nicolaos Antonio Cutululis
Wind Energ. Sci., 7, 925–942, https://doi.org/10.5194/wes-7-925-2022, https://doi.org/10.5194/wes-7-925-2022, 2022
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Wind farms are becoming larger, and they are shaping up as one of the main drivers towards full green energy transition. Because of their massive proliferation, more and more attention is nowadays focused on optimal design of these power plants. We propose an optimization framework in order to contribute to further cost reductions, by simultaneously designing the wind turbines and cable layout. We show the capability of the framework to improve designs compared to the classic approach.
Andreas Rott, Jörge Schneemann, Frauke Theuer, Juan José Trujillo Quintero, and Martin Kühn
Wind Energ. Sci., 7, 283–297, https://doi.org/10.5194/wes-7-283-2022, https://doi.org/10.5194/wes-7-283-2022, 2022
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We present three methods that can determine the alignment of a lidar placed on the transition piece of an offshore wind turbine based on measurements with the instrument: a practical implementation of hard targeting for north alignment, a method called sea surface levelling to determine the levelling of the system from water surface measurements, and a model that can determine the dynamic levelling based on the operating status of the wind turbine.
Matthias Kretschmer, Jason Jonkman, Vasilis Pettas, and Po Wen Cheng
Wind Energ. Sci., 6, 1247–1262, https://doi.org/10.5194/wes-6-1247-2021, https://doi.org/10.5194/wes-6-1247-2021, 2021
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We perform a validation of the new simulation tool FAST.Farm for the prediction of power output and structural loads in single wake conditions with respect to measurement data from the offshore wind farm alpha ventus. With a new wake-added turbulence functionality added to FAST.Farm, good agreement between simulations and measurements is achieved for the considered quantities. We hereby give insights into load characteristics of an offshore wind turbine subjected to single wake conditions.
Aurélien Babarit, Félix Gorintin, Pierrick de Belizal, Antoine Neau, Giovanni Bordogna, and Jean-Christophe Gilloteaux
Wind Energ. Sci., 6, 1191–1204, https://doi.org/10.5194/wes-6-1191-2021, https://doi.org/10.5194/wes-6-1191-2021, 2021
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In this paper, a new energy system for the conversion of far-offshore wind energy into methanol is proposed, and the cost of energy is estimated. Results show that this system could produce approximately 70 000 t of methanol per annum at a cost comparable to that of methanol produced by offshore wind farms in the long term.
Romanas Puisa, Victor Bolbot, Andrew Newman, and Dracos Vassalos
Wind Energ. Sci., 6, 273–286, https://doi.org/10.5194/wes-6-273-2021, https://doi.org/10.5194/wes-6-273-2021, 2021
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The paper proposes a quantitative, non-probabilistic metric for the preliminary comparison of safety of windfarm service operation vessels (SOV) in typical phases of operation. The metric is used as a conditional proxy for the incident likelihood, conditioned upon the presence of similar resources (manpower, time, skills, knowledge, information, etc.) for risk management across compared operational phases.
Simone Mancini, Koen Boorsma, Marco Caboni, Marion Cormier, Thorsten Lutz, Paolo Schito, and Alberto Zasso
Wind Energ. Sci., 5, 1713–1730, https://doi.org/10.5194/wes-5-1713-2020, https://doi.org/10.5194/wes-5-1713-2020, 2020
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This work characterizes the unsteady aerodynamic response of a scaled version of a 10 MW floating wind turbine subjected to an imposed platform motion. The focus has been put on the simple yet significant motion along the wind's direction (surge). For this purpose, different state-of-the-art aerodynamic codes have been used, validating the outcomes with detailed wind tunnel experiments. This paper sheds light on floating-turbine unsteady aerodynamics for a more conscious controller design.
Robbie Herring, Kirsten Dyer, Paul Howkins, and Carwyn Ward
Wind Energ. Sci., 5, 1399–1409, https://doi.org/10.5194/wes-5-1399-2020, https://doi.org/10.5194/wes-5-1399-2020, 2020
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Leading edge erosion has developed into a significant problem for the offshore wind industry. It is important to understand the offshore precipitation environment to model and predict the onset of erosion and to design systems to protect against it. In this study, the offshore environment was characterised using up-to-date measuring techniques. A general offshore droplet size distribution that can be used to improve lifetime prediction techniques has been presented.
Tobias Ahsbahs, Galen Maclaurin, Caroline Draxl, Christopher R. Jackson, Frank Monaldo, and Merete Badger
Wind Energ. Sci., 5, 1191–1210, https://doi.org/10.5194/wes-5-1191-2020, https://doi.org/10.5194/wes-5-1191-2020, 2020
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Before constructing wind farms we need to know how much energy they will produce. This requires knowledge of long-term wind conditions from either measurements or models. At the US East Coast there are few wind measurements and little experience with offshore wind farms. Therefore, we created a satellite-based high-resolution wind resource map to quantify spatial variations in the wind conditions over potential sites for wind farms and found larger variation than modelling suggested.
Anna-Maria Tilg, Charlotte Bay Hasager, Hans-Jürgen Kirtzel, and Poul Hummelshøj
Wind Energ. Sci., 5, 977–981, https://doi.org/10.5194/wes-5-977-2020, https://doi.org/10.5194/wes-5-977-2020, 2020
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Recently, there has been an increased awareness of leading-edge erosion of wind turbine blades. An option to mitigate the erosion at the leading edges is the deceleration of the wind turbine blades during severe precipitation events. This work shows that a vertically pointing radar can be used to nowcast precipitation events with the required spatial and temporal resolution. Furthermore, nowcasting allows a reduction in the rotational speed prior to the impact of precipitation on the blades.
Aurélien Babarit, Gaël Clodic, Simon Delvoye, and Jean-Christophe Gilloteaux
Wind Energ. Sci., 5, 839–853, https://doi.org/10.5194/wes-5-839-2020, https://doi.org/10.5194/wes-5-839-2020, 2020
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This paper addresses the topic of far-offshore wind energy exploitation. Far-offshore wind energy exploitation is not feasible with grid-connected floating wind turbines because grid-connection cost, installation cost and O&M cost would be prohibitive. An enabling technology is the energy ship concept, which is described and modeled in the paper. A design of an energy ship is proposed. It is estimated that it could produce 5 GWh per annum of chemical energy (methanol).
Michael Denis Mifsud, Tonio Sant, and Robert Nicholas Farrugia
Wind Energ. Sci., 5, 601–621, https://doi.org/10.5194/wes-5-601-2020, https://doi.org/10.5194/wes-5-601-2020, 2020
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In offshore wind, it is important to have an accurate wind resource assessment. Measure–correlate–predict (MCP) is a statistical method used in the assessment of the wind resource at a candidate site. Being a statistical method, it is subject to uncertainty, resulting in an uncertainty in the power output from the wind farm. This study involves the use of wind data from the island of Malta and uses a hypothetical wind farm to establish the best MCP methodology for the wind resource assessment.
Aurélien Babarit, Simon Delvoye, Gaël Clodic, and Jean-Christophe Gilloteaux
Wind Energ. Sci. Discuss., https://doi.org/10.5194/wes-2019-101, https://doi.org/10.5194/wes-2019-101, 2020
Revised manuscript not accepted
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This paper addresses the topic of far-offshore wind energy exploitation. Far-offshore wind energy exploitation is not feasible with current technology because grid-connection cost, installation cost and O&M cost would be prohibitive. An enabling technology for far-offshore wind energy is the energy ship concept, which has been described, modelled and analyzed in a companion paper. This paper provides a cost model and cost estimates for an energy system based on the energy ship concept.
Amber Kapoor, Slimane Ouakka, Sanjay R. Arwade, Julie K. Lundquist, Matthew A. Lackner, Andrew T. Myers, Rochelle P. Worsnop, and George H. Bryan
Wind Energ. Sci., 5, 89–104, https://doi.org/10.5194/wes-5-89-2020, https://doi.org/10.5194/wes-5-89-2020, 2020
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Offshore wind energy is a burgeoning area of renewable energy that is at an early stage of development in the United States. Exposure of offshore wind turbines to hurricanes must be assessed and mitigated to ensure the security of the renewable energy supply. This research assesses the impact of hurricane wind fields on the structural response of wind turbines. Such wind fields have characteristics that may pose heretofore unforeseen structural challenges to offshore wind turbines.
Jakob Ilsted Bech, Charlotte Bay Hasager, and Christian Bak
Wind Energ. Sci., 3, 729–748, https://doi.org/10.5194/wes-3-729-2018, https://doi.org/10.5194/wes-3-729-2018, 2018
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Rain erosion on wind turbine blades is a severe challenge for wind energy today. It causes significant losses in power production, and large sums are spent on inspection and repair.
Blade life can be extended, power production increased and maintenance costs reduced by rotor speed reduction at extreme precipitation events. Combining erosion test results, meteorological data and models of blade performance, we show that a turbine control strategy is a promising new weapon against blade erosion.
Tobias Ahsbahs, Merete Badger, Patrick Volker, Kurt S. Hansen, and Charlotte B. Hasager
Wind Energ. Sci., 3, 573–588, https://doi.org/10.5194/wes-3-573-2018, https://doi.org/10.5194/wes-3-573-2018, 2018
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Satellites offer wind measurements offshore and can resolve the wind speed on scales of up to 500 m. To date, this data is not routinely used in the industry for planning wind farms. We show that this data can be used to predict local differences in the mean wind speed around the Anholt offshore wind farm. With satellite data, site-specific wind measurements can be introduced early in the planning phase of an offshore wind farm and help decision makers.
Sebastian Schafhirt and Michael Muskulus
Wind Energ. Sci., 3, 25–41, https://doi.org/10.5194/wes-3-25-2018, https://doi.org/10.5194/wes-3-25-2018, 2018
Lisa Ziegler, Ursula Smolka, Nicolai Cosack, and Michael Muskulus
Wind Energ. Sci., 2, 469–476, https://doi.org/10.5194/wes-2-469-2017, https://doi.org/10.5194/wes-2-469-2017, 2017
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The first larger offshore wind farms are reaching a mature age. Operators have to take actions for monitoring now in order to have accurate knowledge on structural reserves later. This knowledge is important to make decisions on lifetime extension. Many offshore wind turbines have one set of strain gauges already installed at the transition piece. We present a simple and robust method to extrapolate these measurements to other locations of the monopile without need of additional instrumentation.
Antonio Jarquin Laguna
Wind Energ. Sci., 2, 387–402, https://doi.org/10.5194/wes-2-387-2017, https://doi.org/10.5194/wes-2-387-2017, 2017
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This paper presents the idea of centralized electricity production in a wind farm by means of water technology. A new way of generating and transmitting wind energy is explored with no intermediate electrical conversion until the energy has reached the central offshore platform. This work includes the modelling and simulations of a hypothetical hydraulic wind farm, where results indicate good performance despite the turbulent wind conditions and wake effects.
Steffen Aasen, Ana M. Page, Kristoffer Skjolden Skau, and Tor Anders Nygaard
Wind Energ. Sci., 2, 361–376, https://doi.org/10.5194/wes-2-361-2017, https://doi.org/10.5194/wes-2-361-2017, 2017
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The industry standard for analysis of monopile foundations is inaccurate, and alternative models for foundation behavior are needed. This study investigates how four different soil-foundation models affect the fatigue damage of an offshore wind turbine with a monopile foundation. Stiffness and damping properties have a noticeable effect, in particular for idling cases. At mud-line, accumulated fatigue damage varied up to 22 % depending on the foundation model used.
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Short summary
The damping of an offshore wind turbine is a difficult physical quantity to predict, although it plays a major role in a cost-effective turbine design. This paper presents a review of all approaches that can be used for damping estimation directly from operational wind turbine data. As each use case is different, a novel suitability table is presented to enable the user to choose the most appropriate approach for the given availability and characteristics of measurement data.
The damping of an offshore wind turbine is a difficult physical quantity to predict, although it...
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