Moment Bearing Test Device for Testing a Moment Bearing of a Wind Turbine and a Method Thereof

Abstract

The invention relates to moment bearing test device and a method of testing a wind turbine moment bearing. The test device comprises a drive unit for rotating a first ring relative to a second ring of the moment bearing. The drive unit is mounted to at least one torque arm rotatably connected to a mounting frame. The mounting frame is configured to be mounted to the first or second ring. The test device further comprises a measuring unit for measuring a friction torque of the moment bearing. The test device acts as a mobile test device allowing the test to be performed on-site and allows the moment bearing to be tested when mounted to the rotor hub or mainframe.

Claims

1. A moment bearing test device for testing a moment bearing of a wind turbine (1), the wind turbine moment bearing comprising a first ring (14) rotatably arranged relative to a second ring (21), where a plurality of rotatable bearing elements are arranged between the first ring (14) and the second ring (21), where the moment bearing test device comprises a mounting frame (13) configured to be mounted to said first ring (14) of the moment bearing, at least one drive unit (20) is rotatably coupled to said mounting frame (13), and at least one measuring unit (24) is configured to measure at least one signal indicative of a friction torque of the moment bearing, wherein the at least one drive unit (20) is configured to rotate said first ring (14) relative to said second ring (21) when mounted, wherein the moment bearing test device further comprises at least one torque arm (15) having at least one mounting interface (19), wherein said at least one torque arm (15) is rotatably connected to the mounting frame (13), and where said at least one drive unit (20) is mounted to said at least one mounting interface (19).

2. A moment bearing test device according to claim 1, wherein said at least one torque arm (15) is rotatably connected to the mounting frame (13) via a four-point bearing system, the bearing system comprises a first bearing element (27) rotatably arranged relative to a second bearing element (28).

3. A moment bearing test device according to claim 1, wherein said at least one mounting interface (19) comprises a first mounting interface and at least a second mounting interface (19) for selective mounting of the at least one drive unit (20).

4. A moment bearing test device according to claim 1, wherein said at least one torque arm (15) comprises a first torque arm extending in a first radial direction and at least a second torque arm (15) extending in at least one second radial direction.

5. A moment bearing test device according to claim 1, wherein said at least one torque arm (15) comprises a free end (18), the free end (18) being connected either directly to the second ring (21) or indirectly via an intermediate element, e.g. the at least one measuring unit (24).

6. A moment bearing test device according to claim 1, wherein said mounting frame (13) comprises a mounting plate on which a plurality of mounting elements are arranged, wherein said plurality of mounting elements is configured to be mounted to complementary mounting elements located on the first ring (14).

7. A moment bearing test device according to claim 6, wherein said at least one drive unit (20) is rotatably coupled to a gear unit (22), the gear unit (22) comprises a first gear element configured to engage a second gear element located on the mounting frame (13), e.g. a first bearing element (14).

8. A moment bearing test device according to claim 1, wherein the moment bearing test device further comprises at least one temperature sensor (24′) arranged relative to at least one of said first (14) and second rings (21) of the moment bearing.

9. A moment bearing test device according to claim 1, wherein said at least one measuring unit (23) is arranged relative to said at least one drive unit (20) and configured to measure at least one operating parameter of the drive unit (20), wherein the friction torque of the moment bearing is calculated based on said at least one operating parameter.

10. A moment bearing test device according to claim 1, wherein the moment bearing test device further comprises at least one set of: support elements (12) configured for placement on a reference surface, or adjustable support elements configured for levelling the moment bearing.

11. A moment bearing test device according to claim 10, wherein the moment bearing test device further comprises a control unit configured to control the operation of the moment bearing test device.

12. A method of determining a friction torque of a wind turbine moment bearing, wherein the method comprises the steps of: providing a wind turbine moment bearing, wherein said wind turbine moment bearing comprises a first ring (14) rotatably arranged relative to a second ring (21), mounting a moment bearing test device according to any claim 1 to said moment bearing, performing at least one test procedure on said moment bearing to determine at least one signal indicative of a friction torque of the wind turbine moment bearing.

13. A method according to claim 12, wherein the method further comprises the steps of: transporting the moment bearing test device to a test site prior to mounting said moment bearing test device, and demounting the moment bearing test device after completing the at least one test procedure.

14. A method according to claim 12, wherein the method further comprises the steps of: providing a wind turbine rotor hub (4) or a wind turbine nacelle (3) comprising at least a mainframe (7), and mounting the moment bearing to said wind turbine rotor hub (4) or said mainframe (7).

Description

DESCRIPTION OF THE DRAWING

[0074] An embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0075] FIG. 1 shows an exemplary embodiment of a wind turbine,

[0076] FIG. 2 shows an exemplary embodiment of a moment bearing arranged between the rotor and the nacelle,

[0077] FIG. 3 shows a first embodiment of a test device according to the invention,

[0078] FIG. 4 shows an exploded view of the test device shown in FIG. 3,

[0079] FIG. 5 shows a second embodiment of the test device according to the invention,

[0080] FIG. 6 shows a second embodiment of the torque arm, and

[0081] FIG. 7 shows an exemplary embodiment of the bearing system.

[0082] In the following text, the figures will be described one by one, and the different parts and positions seen in the figures will be numbered with the same numbers in the different figures. Not all parts and positions indicated in a specific figure will necessarily be discussed together with that figure.

Position Number List

[0083] 1. Wind turbine [0084] 2. Wind turbine tower [0085] 3. Nacelle [0086] 4. Hub [0087] 5. Wind turbine blades [0088] 6. Moment bearing [0089] 7. Mainframe [0090] 8. First mounting interface [0091] 9. Second mounting interface [0092] 10. Mounting interfaces for wind turbine blades [0093] 11. Test device [0094] 12. Support elements [0095] 13. Mounting frame [0096] 14. First ring of moment bearing [0097] 15. Torque arms [0098] 16. Bearing system [0099] 17. Central part [0100] 18. Free ends [0101] 19. Mounting interfaces for drive unit [0102] 20. Drive unit [0103] 21. Second ring of moment bearing [0104] 22. Gear unit [0105] 23. Control unit [0106] 24. Measuring units [0107] 25. First mounting element [0108] 26. Second mounting element [0109] 27. First bearing element [0110] 28. Second bearing element [0111] 29. Rotatable bearing elements [0112] 30. Gear elements [0113] 31. Seal elements

DETAILED DESCRIPTION OF THE INVENTION

[0114] FIG. 1 shows an exemplary embodiment of a wind turbine 1 comprising a moment bearing (shown in FIG. 2) according to the invention. The wind turbine 1 further comprising a wind turbine tower 2 arranged on a foundation. The foundation is here shown as an onshore foundation, but also an offshore foundation may be used. A nacelle 3 is arranged on the wind turbine tower 2, e.g. via a yaw bearing system. A rotor is rotatably arranged relative to the nacelle 3 and comprises a hub 4 mounted to at least two wind turbine blades 5, e.g. via a pitch bearing system.

[0115] The wind turbine blades 5 are here shown as full-span wind turbine blades, but also partial-pitchable wind turbine blades may be used. The partial-pitchable wind turbine blade comprises an inner blade section and an outer blade section, wherein a pitch bearing system is arranged between the two blade sections.

[0116] FIG. 2 shows an exemplary embodiment of the moment bearing 6 arranged between the rotor and the nacelle 3. Here, only the hub 4 of the rotor and a mainframe 7 of the nacelle 3 are shown for illustrative purposes. The moment bearing 6 is configured to at least transfer moment loads from the rotor to the nacelle 3, e.g. the mainframe 7. The hub 4 comprises a first mounting interface 8 facing the nacelle 3 and the mainframe 7 comprises a second mounting interface 9 facing the rotor 3. The hub 4 further comprises at least two other mounting interfaces 10 facing in a direction of the rotor. The individual mounting interfaces 10 is configured to be mounted to a corresponding mounting interface (not shown) on the respective wind turbine blades (shown in FIG. 1). The moment bearing 6 is mounted to the first and second mounting interfaces 8, 9 respectively.

[0117] FIG. 3 shows a first embodiment of a test device 11 for testing the moment bearing 6 of the wind turbine 1. In this embodiment, the test device 11 is mounted to the moment bearing 6 using a plurality of support elements 12. The support elements 12 are mounted to one side of the moment bearing 6 and are configured to be positioned relative to a reference surface (not shown). The test device 11 is mounted to the opposite side of the moment bearing 6 as shown in FIG. 3. This enables the moment bearing 6 to be tested separately before being mounted to the hub 4 or mainframe 7.

[0118] FIG. 4 shows an exploded view of the test device 11 comprising a mounting frame 13 in the form of a mounting plate having a plurality of mounting elements, e.g. mounting holes, configured to be mounted to complementary mounting elements, e.g. mounting holes, on a first ring 14 of the moment bearing 6. Here, the mounting frame 13 is mounted using separate fastening means in the form of bolts and nuts. This enables the first ring 14 to follow the rotation of the mounting frame 13 during testing.

[0119] The mounting frame 13 is rotatably coupled to a plurality of torque arms 15 by means of a bearing system 16. The bearing system 16 is configured as a four-point bearing system (shown in FIG. 7). In the embodiment shown in FIG. 4, a first and a second torque arm are formed by a single piece having a central part 17 and two free ends 18. The first and second torque arms 15 extend in opposite facing radial directions.

[0120] The first and second torque arms 15 comprise a plurality of mounting interfaces 19 configured to be mounted to a drive unit 20. Here, a first and a second mounting interfaces are arranged in the central part 17 for selective mounting of the drive unit 20. The drive unit 20 is configured to rotate the mounting frame 13 and, thus, the first ring 14 relative to a second ring 21 of the moment bearing 6. Here, the drive unit 20 is shown as a motor rotatably coupled to a gear unit 22 which, in turn, interacts with the bearing system 16. The operation of the test device 11, e.g. the speed or frequency of the motor, may be controlled by means of a control unit 23.

[0121] A measuring unit 24 is arranged at either free end 18 of the torque arms 15 for optimal measurement of the friction torque of the moment bearing 6. Here, the measuring unit 24 is configured to measure a friction force which, in turn, is used to calculate the friction torque. Each measuring unit 24 acts as an intermediate element connected to a first mounting element 25 selectively mounted to a complementary mounting element on the second ring 21. The first mounting element 25 defines a mounting point for the measuring unit 24. A second mounting element 26 is arranged relative to the first mounting element 25. The second mounting 26 defines a stop position for the torque arm 15. This limits the rotational movement of the torque arm 15 during testing.

[0122] Another measuring unit 24′ in the form of a temperature sensor is optionally arranged relative to the first ring 14 and/or the second ring 21 for measuring a temperature of the respective ring 14, 21. This allows the test device 11 to further measure a temperature, e.g. a differential temperature, of the moment bearing 6.

[0123] The support elements 12 are further mounted to the complementary mounting elements on the second ring 21 of the moment bearing as shown in FIGS. 3 and 4.

[0124] FIG. 5 shows a second embodiment of the test device 11′ according to the invention. In this embodiment, the support elements 12 are omitted and the test device 11′ is mounted after mounting the moment bearing 6 to the mainframe 7 or hub 4. Here, the moment bearing 6 is mounted to the mainframe 7. This enables the moment bearing 6 to be tested when mounted to the mainframe 7 or hub 4 respectively.

[0125] The test device 11, 11′ shown in FIGS. 3 and 5 is configured as a mobile test device which can be transported to a desired test site, such as the installation site, the assembly site, or the manufacturing site. The configuration of the test device 11, 11′ allows the worker at the test site to mount the test device 11, 11′ in a quick and simple manner and then perform one or simple tests of the moment bearing 6. After completion of the tests, the test device 11, 11′ can be demounted in a quick and simple manner and transported to another test site or mounted to another moment bearing. The same test device 11, 11′ can thus be used to test the moment bearing after assembly as well as before and after mounting of the moment bearing.

[0126] FIG. 6 shows a second embodiment of the torque arm 15′ having a central part 17′ and only one free end 18′. A single measuring unit (not shown) may thus be arranged at the free end 18′ and connected to the first mounting element 25. This allows the friction force to be measured in a single point whereas the torque arm in FIGS. 3 and 4 allows the friction force to be measured in a plurality of points.

[0127] FIG. 7 shows an exemplary embodiment of the bearing system 16 wherein the bearing system comprises a first bearing element 27 rotatably arranged relative to a second bearing element 28. The first bearing element 27 is configured to be mounted to the mounting frame 13. A plurality of rotatable bearing elements 29 are arranged between the first and second bearing elements 27, 28. The respective contact surfaces between the bearing elements 29 and the bearing elements 27, 28 are shaped so that they form a four-point contact bearing system.

[0128] This enables axial and radial forces in both directions to be transferred between the torque arm 15, 15′ and the mounting frame 13.

[0129] The second bearing element 28 comprises a plurality of gear elements 30 configured to interact with a complementary gear element located on the drive unit 20, e.g. the gear unit 22. The respective gear elements may be configured as a pinion and an annular gear with engaging teeth as shown in FIG. 4.

[0130] The spacing between the first and second bearing elements 27, 28 is optionally sealed off by means of suitable seal elements 31 arranged at either ends as shown in FIG. 7. The spacing may further be partly or fully filled with a lubricant, such as oil or grease.