SHAFT-TO-SHAFT CONNECTOR FOR A WIND TURBINE

Abstract

Provided is a wind turbine including: a tower, a nacelle mounted on the tower, an electrical generator housed in the nacelle, a wind rotor rotatably coupled to the nacelle for rotating about a rotational axis and having at least one rotatable blade, two rotating shafts for connecting the wind rotor to the electrical generator, a shaft connector for rigidly connecting the two rotating shafts. The shaft connector includes: a hollow body, at least an inner flange protruding from the hollow body towards an axis of rotation of the shaft connector, the inner flange being connectable to one of the two rotating shafts, at least one hole provided on the hollow body for accessing the inner flange.

Claims

1. A wind turbine including: a tower, a nacelle mounted on the tower, an electrical generator housed in the nacelle, a wind rotor rotatably coupled to the nacelle for rotating about a rotational axis and having at least one rotatable blade, two rotating shafts for connecting the wind rotor to the electrical generator, a shaft connector for rigidly connecting the two rotating shafts, wherein the shaft connector having: a hollow body, at least an inner flange protruding from the hollow body towards an axis of rotation of the shaft connector, the inner flange being connectable to one of the two rotating shafts, at least one hole provided on the hollow body for accessing the inner flange.

2. The wind turbine as claimed in claim 1, wherein the shaft connector comprises a second flange being connectable to the other of the two rotating shafts.

3. The wind turbine as claimed in claim 2, wherein the second flange is an outer flange protruding from the hollow body outwards with respect to the axis of rotation.

4. The wind turbine as claimed in claim 1, wherein the hollow body is cylindrical, the axis of rotation being the geometric axis of the the hollow body.

5. The wind turbine as claimed in claim 4, wherein at least one hole is provided on a lateral wall of the hollow body.

6. The wind turbine as claimed in claim 4, wherein the inner flange is provided at one base of the cylindrical hollow body and the second flange is provided at the other base of the cylindrical hollow body.

7. The wind turbine as claimed in claim 1, wherein the inner flange is removably connectable to one of the two rotating shafts.

8. The wind turbine as claimed in claim 1, wherein the second flange is removably connectable to the other of the two rotating shafts.

9. The wind turbine as claimed in claim 7, wherein the inner flange and the second flange is removably connectable to the respective rotating shafts by a respective plurality of bolts or a respective plurality of shear pins.

10. The wind turbine as claimed in claim 1, wherein the two rotating shafts include a rotor shaft connected to the wind rotor and an input shaft of a gearbox interposed between the wind rotor and the electrical generator.

11. The wind turbine as claimed in claim 1, wherein the shaft connector comprises at least one strain measurement device for determining loads transmitted between the two rotating shafts.

12. The wind turbine as claimed in claim 11, wherein the at least one strain measurement device is installed on a surface of the the hollow body.

Description

BRIEF DESCRIPTION

[0019] Some of the embodiments will be described in detail, with reference to the following figures, wherein like designations denote like members, wherein:

[0020] FIG. 1 shows a schematic section of a wind turbine;

[0021] FIG. 2 shows a lateral view of a flanged connection for a wind turbine obtained with the present invention;

[0022] FIG. 3 shows a sectional view of a flanged connection of FIG. 2;

[0023] FIG. 4 shows a more detailed view of the flanged connection of FIG. 2; and

[0024] FIG. 5 shows a second embodiment of a flanged connection for a wind turbine obtained with the present invention.

DETAILED DESCRIPTION

[0025] The illustrations in the drawings are schematic. It is noted that in different figures, similar or identical elements are provided with the same reference signs.

[0026] FIG. 1 shows a wind turbine 1 according to embodiments of the invention. The wind turbine 1 comprises a tower 2, which is mounted on a non-depicted foundation. A nacelle 3 is arranged on top of the tower 2. In between the tower 2 and the nacelle 3 a yaw angle adjustment device (not shown) is provided, which is capable of rotating the nacelle around a vertical yaw axis. The wind turbine 1 further comprises a wind rotor 5 having two, three or more blades 4 (in the perspective of FIG. 1 only two blades 4 are visible). The wind rotor 5 is rotatable around a rotational axis Y. When not differently specified, the terms axial, radial and circumferential in the following are made with reference to the rotational axis Y.

[0027] The blades 4 extend radially with respect to the rotational axis Y. The wind turbine 1 comprises an electrical generator 10. The wind rotor 5 is rotationally coupled with the electrical generator 10 by means of a rotatable main shaft 30 and a gearbox (not shown in FIG. 1). A schematically depicted bearing assembly 8 is provided in order to hold in place the main shaft 30. The rotatable main shaft 30 extends along the rotational axis Y. The permanent magnet electrical generator 10 includes a stator 11 and a rotor 12. The rotor 12 is radially external to the stator 11 and is rotatable with respect to the stator 11 about the rotational axis Y. According to other embodiments of the present invention (not shown) the rotor is radially internal to the stator 11. The gearbox transfer torque from the rotatable main shaft 30 to the rotor 12, which are rotating at different rotational speeds. The rotor 12 is normally rotating at a higher speed than the rotatable main shaft 30, which may be also referred to as low speed shaft

[0028] With reference to FIGS. 2 to 5, the gearbox interposed between the main shaft 30 and the rotor 12 of the electrical generator 10 includes a gearbox input shaft 40. The main shaft 30 and the gearbox input shaft 40 are rigidly connecting to each other through a shaft connector 50. In operation the shaft connector 50 rotates around an axis of rotation W, which may be parallel or aligned to the rotational axis Y. The shaft connector 50 comprises a hollow body 51 having a central cavity and at least an inner flange 52 protruding from the hollow body 51 towards the axis of rotation W. The inner flange is removably connectable to the main shaft 30 by means of a first plurality of removable connections 56. The removable connections 56 may be bolts or shear pins or similar mechanical elements coupled through respective pluralities of coupling holes provide on the main shaft 30 and on the inner flange 52. According to an embodiment of the invention (not shown) the inner flange is removably connectable to the gearbox input shaft 40. At least at least one access hole 54 is provided on the hollow body 51 for accessing the inner cavity and through this the inner flange 52. According to embodiments of the present invention, a plurality of holes 54 may be provided on the hollow body 51 for accessing the inner cavity and through this the inner flange 52. The plurality of holes may be regularly distributed around the axis of rotation W. In the embodiments where the hollow body 51 is cylindrical the one or more one holes 54 are provided on a lateral cylindrical wall of the hollow body 51. The access hole(s) 54 permit to access the inner flange 52 and the removable connections 56 for mounting, inspection and maintenance. The position and dimensions of the access hole(s) 54 depend on the tools dimensions being used during mounting, inspection and maintenance.

[0029] On the shaft connector 50 at least one strain measurement device 58 may be installed. In particular, at least one strain measurement device 58 may be installed on a surface of the hollow body 51. By post-processing the signal outputted by strain measurement device 58, loads that go from the main shaft 30 to the gearbox input shaft 40 may be calculated.

[0030] The shaft connector 50 comprises a second outer flange 53 protruding from the hollow body 51 outwards with respect to the axis of rotation W. The second outer flange 53 is removably connectable to the the gearbox input shaft 40 by means of a second plurality of removable connections 57. The removable connections 57 may be bolts or shear pins or similar mechanical elements coupled through respective pluralities of coupling holes provide on the gearbox input shaft 40 and on the second outer flange 53. In the embodiment of the invention where the inner flange 52 is removably connectable to the gearbox input shaft 40, the second outer flange 53 is removably connectable to the the main shaft 30.

[0031] According to an embodiment of the invention shown in FIG. 5, the second flange 53 is also an inner flange protruding from the hollow body 51 towards the axis of rotation W. in such embodiment the access hole(s) 54 permit to access both the two inner flanges and the respective removable connections 56, 57 for mounting, inspection and maintenance.

[0032] The hollow body 51 may be cylindrical, the axis of rotation W being the geometric axis of the the hollow body 51. The inner flange 52 may be provided at one base of the cylindrical hollow body 51 and the second outer flange 53 may be provided at the other base of the cylindrical hollow body 51.

[0033] Although the present invention has been disclosed in the form of preferred embodiments and variations thereon, it will be understood that numerous additional modifications and variations could be made thereto without departing from the scope of the invention.

[0034] For the sake of clarity, it is to be understood that the use of a or an throughout this application does not exclude a plurality, and comprising does not exclude other steps or elements.