Articles | Volume 8, issue 10
https://doi.org/10.5194/wes-8-1495-2023
© Author(s) 2023. 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-8-1495-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
09 Oct 2023
Research article |
| 09 Oct 2023
| 09 Oct 2023
The effect of site-specific wind conditions and individual pitch control on wear of blade bearings
Arne Bartschat
CORRESPONDING AUTHOR
Fraunhofer Institute for Wind Energy Systems IWES, Large Bearing Laboratory Am Schleusengraben 22, 21029 Hamburg, Germany
Karsten Behnke
Fraunhofer Institute for Wind Energy Systems IWES, Large Bearing Laboratory Am Schleusengraben 22, 21029 Hamburg, Germany
Matthias Stammler
Fraunhofer Institute for Wind Energy Systems IWES, Large Bearing Laboratory Am Schleusengraben 22, 21029 Hamburg, Germany
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Matthis Graßmann, Marlene Bantz, Frank Schönberg, and Arne Bartschat
Wind Energ. Sci. Discuss., https://doi.org/10.5194/wes-2026-192, https://doi.org/10.5194/wes-2026-192, 2026
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Wind turbine blade bearings rely on seals to keep lubricant inside and dirt outside. This study examined how much these bearings deform during operation and whether lubricant pressure could threaten seal performance. Using finite element simulations and original-size tests, this work found that ring deformation remained well within the seal's capability. Pressure stayed very low during normal operation and only increased under unrealistic extreme conditions.
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Wind turbine blade bearings rely on seals to keep lubricant inside and dirt outside. This study examined how much these bearings deform during operation and whether lubricant pressure could threaten seal performance. Using finite element simulations and original-size tests, this work found that ring deformation remained well within the seal's capability. Pressure stayed very low during normal operation and only increased under unrealistic extreme conditions.
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This study compares traditional and artificial intelligence supported methods for detecting damage in rotating machine parts. Bearings were tested under controlled conditions to see how well each method identified developing problems. The artificial intelligence supported method detected damage as early as, or earlier than, established techniques while needing far less expert attention. This supports automated monitoring of wind turbines, enabling earlier maintenance and lower operating costs.
Bruno Rodrigues Faria, Nikolay Dimitrov, Nikhil Sudhakaran, Matthias Stammler, Athanasios Kolios, W. Dheelibun Remigius, Xiaodong Zhang, and Asger Bech Abrahamsen
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This study presents continuous lifetime assessments of wind turbine structural (tower) and rotating components (main bearings) over nearly a decade, combining controller data, calibrated load measurements, and a virtual load sensor at the tower bottom. The components' estimated lifetimes exceeded the design lifetime. Contrary to expectations, lower turbulence intensity at rated wind speed increased fatigue loads of the locating main bearing due to turbulence averaging.
Oliver Menck, Florian Schleich, and Matthias Stammler
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The paper discusses how to calculate the life of a blade bearing that is a roller bearing, as opposed to ball bearings, which most papers on the subject discuss. The raceway fatigue life of the bearing is calculated in a very detailed manner. This includes a validated finite-element simulation model and an approach to determine loads for all operating conditions that the wind turbine experiences.
Matthias Stammler and Florian Schleich
Wind Energ. Sci., 10, 813–826, https://doi.org/10.5194/wes-10-813-2025, https://doi.org/10.5194/wes-10-813-2025, 2025
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The structures at the center of wind turbine rotors are loaded by three rotor blades. The rotor blades have different loads, which depend on their positions and the incoming wind. The number of possible different loads is too high to simulate each of them for later design of the structures. This work attempts to reduce the number of necessary simulations by exploring inherent relations between the loads of the three rotor blades.
Oliver Menck and Matthias Stammler
Wind Energ. Sci., 9, 777–798, https://doi.org/10.5194/wes-9-777-2024, https://doi.org/10.5194/wes-9-777-2024, 2024
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Oscillating bearings, like rotating bearings, can fail due to rolling contact fatigue. But the publications in the literature on this topic are difficult to understand. In order to help people decide which method to use, we have summarized the available literature. We also point out some errors and things to look out for to help engineers that want to calculate the rolling contact fatigue life of an oscillating bearing.
Matthias Stammler
Wind Energ. Sci., 8, 1821–1837, https://doi.org/10.5194/wes-8-1821-2023, https://doi.org/10.5194/wes-8-1821-2023, 2023
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Wind turbines subject their components to highly variable loads over very long lifetimes. Tests of components like the pitch bearings that connect rotor blades and the rotor hub serve to validate their ability to withstand these loads. Due to the complexity of the operational loads, the definition of test programs is challenging. This work outlines a method that defines wear test programs for specific pitch bearings and gives a case study for an example turbine.
Karsten Behnke and Florian Schleich
Wind Energ. Sci., 8, 289–301, https://doi.org/10.5194/wes-8-289-2023, https://doi.org/10.5194/wes-8-289-2023, 2023
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The objective of this work is to find limits within typical operating conditions of a wind turbine below which wear on the bearing raceway does not occur. It covers the test of blade bearings with an outer diameter of 2.6 m. The test parameters are based on a 3 MW reference turbine and are compared to values from the literature. It was shown that it can be possible to avoid wear, which again can be used to design a wind turbine controller.
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Short summary
Blade bearings are among the most stressed and challenging components of a wind turbine. Experimental investigations using different test rigs and real-size blade bearings have been able to show that rather short time intervals of only several hours of turbine operation can cause wear damage on the raceways of blade bearings. The proposed methods can be used to assess wear-critical operation conditions and to validate control strategies as well as lubricants for the application.
Blade bearings are among the most stressed and challenging components of a wind turbine....
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