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Wind Turbine Windturbine Éolienne (19) *EP003460238B1* (11) EP 3 460 238 B1 (12) EUROPEAN PATENT SPECIFICATION (45) Date of publication and mention (51) Int Cl.: of the grant of the patent: F03D 1/06 (2006.01) F03D 80/70 (2016.01) (2006.01) 15.04.2020 Bulletin 2020/16 F16C 21/00 (21) Application number: 17192101.8 (22) Date of filing: 20.09.2017 (54) WIND TURBINE WINDTURBINE ÉOLIENNE (84) Designated Contracting States: • Olesen, Dennis AL AT BE BG CH CY CZ DE DK EE ES FI FR GB 8200 Aarhus (DK) GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO • Thomsen, Kim PL PT RO RS SE SI SK SM TR 9520 Skørping (DK) • Thorhauge, Morten (43) Date of publication of application: 8200 Aarhus (DK) 27.03.2019 Bulletin 2019/13 (74) Representative: Aspacher, Karl-Georg (73) Proprietor: Siemens Gamesa Renewable Energy Siemens Gamesa Renewable Energy GmbH & Co. A/S KG 7330 Brande (DK) Otto-Hahn-Ring 6 81739 München (DE) (72) Inventors: • Frydendal, Niels Karl (56) References cited: 7400 Herning (DK) EP-A1- 2 568 167 EP-A1- 2 568 168 • Kanstrup, Troels WO-A1-2013/042294 US-A1- 2013 287 574 8763 Rask Moelle (DK) Note: Within nine months of the publication of the mention of the grant of the European patent in the European Patent Bulletin, any person may give notice to the European Patent Office of opposition to that patent, in accordance with the Implementing Regulations. Notice of opposition shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention). EP 3 460 238 B1 Printed by Jouve, 75001 PARIS (FR) 1 EP 3 460 238 B1 2 Description vide an improved wind turbine. [0007] Accordingly, a wind turbine according to claim [0001] The present invention relates to a wind turbine. 1 is provided. The wind turbine comprises a hub, a shaft [0002] Modern wind turbine rotor blades are built from which is connected to the hub, a bearing housing, in fiber-reinforced plastics. A rotor blade typically compris- 5 which the shaft is supported rotatable, wherein the shaft es an airfoil having a rounded leading edge and a sharp is arranged inside the bearing housing, a fluid bearing trailing edge. The rotor blade is connected with its blade which supports the shaft in the bearing housing, wherein root to a hub of the wind turbine. The increasing size of the fluid bearing is arranged at a proximal end of the wind turbines and the trend towards offshore turbines shaft, wherein the proximal end of the shaft is positioned puts high demands on serviceability and robustness of 10 proximal to the hub, and a roller bearing which also sup- the bearings of a shaft of the wind turbine. Also due to ports the shaft in the bearing housing, wherein the roller fact that large wind turbines have large dynamic shaft bearing is arranged at a distal end of the shaft, and where- deflections, high loads and low speeds makes it chal- in the distal end of the shaft is positioned distal to the hub. lenging for bearings to work and last the demanded life- [0008] The fluid bearing provides a bearing type with time. Conventional wind turbine designs using roller 15 high load capacity and scalability to even large wind tur- bearings or ball bearings for carrying a drive train, a gen- bines. The fluid bearing is also easy to make exchange- erator on direct drive wind turbines and the hub with able in-situ if a segmented bearing is used. The combi- blades require external crane capacity if a main bearing nation of the fluid bearing at an upwind location of the needs replacement. This type of service is very costly, shaft and the roller bearing at a downwind location of the especially for wind turbines located offshore. 20 shaft is a cost effective and low weight solution. The high- [0003] EP 2 568 167 A1 describes a direct-drive wind er loaded fluid bearing can be easily exchanged when it turbine, wherein a rotor of the wind turbine is directly con- is segmented. A cost effective and light turbine structure nected to a rotating drive train of the wind turbine. The can be provided that allows for in-situ replacement of all rotating drive train is connected with a stationary part of main bearings. No crane or crane vessel is needed to the wind turbine via at least one bearing, which allows 25 replace the main bearings. the rotation of the drive train in relation to the stationary [0009] The position where the fluid bearing is arranged part. The at least one bearing is a plain bearing. The can be named upwind position or upwind location. The bearing comprises at least one cylindrical sliding surface fluid bearing can therefore be named proximal bearing, constructed to support radial loads present in the drive proximal main bearing, upwind bearing or upwind main train. The bearing comprises at least two radial bearing 30 bearing. The position where the roller bearing is arranged surfaces constructed to support axial loads and bending can be named downwind position or downwind location. moments present in the drive train. The surface areas of The roller bearing can therefore be named distal bearing, the radial bearing surfaces are dimensioned proportional distal main bearing, downwind bearing or downwind main to a predetermined maximum total load of the bending bearing. The proximal end of the shaft can be named first moments expected in the drive train. 35 end, and the distal end of the shaft can be named second [0004] US 2013/0287574 A1 describes a wind turbine. end. "Proximal" means close to the hub and "distal" The wind turbine includes a stationary main shaft ar- means away from the hub, i.e. not close to the hub. ranged within a nacelle of the wind turbine, a rotor hub [0010] A shaft arrangement of the wind turbine com- including a hollow shell defining an interior and a plurality prises the bearing housing, the shaft, the roller bearing of rotor blades extending radially outwards from the rotor 40 and the fluid bearing. A roller bearing, rolling-element hub, wherein the rotor hub is rotatably mounted to the bearing or rolling bearing preferably is a bearing which stationary main shaft via at least one bearing, wherein carries a load by placing rolling elements (such as balls the at least one bearing is arranged within the interior of or rollers) between two bearing rings called races. The the rotor hub and connected to a section of the main shaft relative motion of the races causes the rolling elements protruding into the interior of the rotor hub. 45 to roll with very little rolling resistance and with little slid- [0005] WO 2013/042294 A1 describes a power gen- ing. The shaft can be rotated in the bearing housing erating apparatus of renewable energy type which is ca- around an axis or rotation axis. The wind turbine further pable of maintaining a concentricity between bearings comprises blades that are connected to the hub. and utilizing the space in a nacelle. The power generating [0011] Fluid bearings or fluid film bearings are bearings apparatus of renewable energy type is provided with a 50 in which the load is supported by a thin layer of rapidly blade, a hub rotating with the blade by the renewable moving pressurized liquid or gas between the bearing energy received via the blade, a rotation shaft connected surfaces. Since there is no contact between the moving to the hub, a pair of bearings for supporting the rotation parts, there is no sliding friction, allowing fluid bearings shaft rotatably, a nacelle including a nacelle base for sup- to have lower friction, wear and vibration than many other porting a bearing housing of each of the bearing from 55 types of bearings. Fluid bearings can be broadly classi- below and a connection frame for connecting upper parts fied into two types: Fluid dynamic bearings (also known of the bearing housings of the bearings. as hydrodynamic bearings) and hydrostatic bearings. [0006] It is one object of the present invention to pro- Hydrostatic bearings are externally pressurized fluid 2 3 EP 3 460 238 B1 4 bearings, where the fluid is usually oil, water or air, and erator is mounted to the proximal end of the shaft. This the pressurization is done by a pump. Hydrodynamic means, the generator is mounted close to the fluid bear- bearings rely on the high speed of the journal (the part ing. When the generator is mounted at the upwind loca- of the shaft resting on the fluid) to pressurize the fluid in tion of the shaft, the roller bearing at the downwind loca- a wedge between the faces. Preferably, the fluid bearing 5 tion can be dismounted and replaced in-situ because the is a hydrostatic bearing. distal end of the shaft is free. In other words, nothing is [0012] According to an embodiment, the fluid bearing mounted to the distal end of the shaft. This type of wind is segmented. This means, the fluid bearing has a bearing turbine can be called direct drive wind turbine. surface that is divided into a variety of segments. These [0020] According to a further embodiment, the gener- segments can be changed individually. 10 ator is mounted to a proximal end of the bearing housing. [0013] According to a further embodiment, the fluid This means, the generator is mounted to the proximal bearing is a tilting pad bearing. A tilting pad bearing has end of the shaft as well as to the proximal end of the sectional shoes, or pads on pivots.
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