Rotor blade assembly for a wind turbine having variable-length blade bolts

Patent metadata

Field	Value
Publication number	US-2016123306-A1
Application number	US-201414531139-A
Country	US
Kind code	A1
Filing date	Nov 3, 2014
Priority date	Nov 3, 2014
Publication date	May 5, 2016
Grant date	—

Abstract

The present disclosure is directed to a rotor blade assembly for a wind turbine that controls pitch bearing load distribution. The assembly includes a rotor blade having a body shell extending between a blade root and tip, a pitch bearing at an interface between the blade root and a hub of the wind turbine, and plurality of blade bolts coupling the blade root to the hub through the pitch bearing. The pitch bearing includes an outer bearing race and an inner bearing race rotatable relative to the outer race. Thus, in one embodiment, the blade bolts couple the blade root to the hub through the inner race of the pitch bearing. Further, each of the blade bolts has a first end and a second end defining a length therebetween and at least two of the blade bolts have varying lengths so as to distribute loads experienced by the pitch bearing.

First claim

What is claimed is:

1 . A rotor blade assembly for a wind turbine, comprising:
a rotor blade including a body shell extending between a blade root and a blade tip; a pitch bearing configured at an interface between the blade root and a hub of the wind turbine, the pitch bearing comprising an outer bearing race and an inner bearing race rotatable relative to the outer race; and, a plurality of blade bolts configured to couple the blade root to the hub through the pitch bearing, each of the blade bolts comprising a first end and a second end defining a length therebetween, wherein at least two of the blade bolts comprise varying lengths so as to evenly distribute loads experienced by the pitch bearing.

2 . The rotor blade assembly of claim 1 , wherein the plurality of blade bolts are configured to couple the blade root to the hub through the inner race of the pitch bearing.

3 . The rotor blade assembly of claim 1 , wherein the plurality of blade bolts comprise a first set of blade bolts having a first length and a second set of blade bolts having a second length, wherein the first length is greater than the second length.

4 . The rotor blade assembly of claim 1 , wherein the blade root comprises a plurality of bolt holes, each of the bolt holes configured to receive one of the plurality of blade bolts.

5 . The rotor blade assembly of claim 4 , wherein the bolt holes comprise varying lengths.

6 . The rotor blade assembly of claim 4 , wherein the bolt holes comprise uniform lengths.

7 . The rotor blade assembly of claim 6 , further comprising a plurality of spacers longitudinally aligned with the plurality of uniform-length bolt holes, wherein the plurality of spacers are configured to accommodate blade bolts of varying lengths.

8 . The rotor blade assembly of claim 7 , wherein the one or more spacers comprise varying lengths.

9 . The rotor blade assembly of claim 1 , further comprising a plurality of barrel nuts configured with the first ends of the plurality of blade bolts.

10 . The rotor blade assembly of claim 1 , further comprising a plurality of attachment nuts configured with the second ends of the plurality of blade bolts.

11 . A system for controlling load distribution in a pitch bearing of a wind turbine, the system comprising:
a plurality of blade bolts configured to couple a blade root of a rotor blade to a hub of the wind turbine through a pitch bearing, each of the plurality of blade bolts comprising a first end and a second end defining a length therebetween, the first ends of the blade bolts configured to extend within a bolt hole of the blade root; and, a plurality of fastening nuts configured to retain the plurality of blade bolts within the bolt holes of the blade root, wherein at least two of the plurality of blade bolts comprise varying lengths so as to evenly distribute loads experienced by the pitch bearing.

12 . The system of claim 11 , further comprising a plurality of spacers configured to longitudinally align with the plurality of bolt holes of the blade root, wherein the plurality of spacers are configured to accommodate the varying lengths of blade bolts of varying lengths.

13 . The system of claim 11 , wherein the fastening nuts comprise at least one of a barrel nut or an attachment nut.

14 . A method for stiffening a connection between a rotor blade and a hub of a wind turbine, the method comprising:
aligning a blade root of the rotor blade with a pitch bearing of the wind turbine, the pitch bearing being operatively coupled to the hub of the wind turbine, the blade root comprising a plurality of bolt holes; longitudinally aligning a plurality of spacers with the plurality of bolt holes; and, inserting a plurality of varying-length blade bolts through the pitch bearing and into the aligned spacers and bolt holes, wherein the varying-length blade bolts are configured to evenly distribute loads experienced by the pitch bearing.

15 . The method of claim 14 , wherein the plurality of bolt holes comprise varying lengths.

16 . The method of claim 14 , wherein the plurality of bolt holes comprise uniform lengths.

17 . The method of claim 16 , wherein the plurality of spacers are configured to accommodate the varying-length blade bolts.

18 . The method of claim 17 , wherein the plurality of spacers comprise varying lengths.

19 . The method of claim 18 , further comprising inserting first ends of the plurality of blade bolts into a plurality of barrel nuts located within the blade root of the rotor blade.

20 . The method of claim 19 , further comprising securing the plurality of blade bolts via a plurality of attachment nuts coupled with second ends of the plurality of blade bolts.

Assignees

• Gen Electric

Inventors

• Minadeo Adam Daniel
• Gobeli William Max
• Caruso Christopher Daniel

Classifications

• F03D1/0658 Primary

  Arrangements for fixing wind-engaging parts to a hub · CPC title

• F03D11/0008 Primary

  Mechanical Engineering · mapped topic

• F05B2260/79

  Bearing, support or actuation arrangements therefor · CPC title

• Y02E10/72

  Wind turbines with rotation axis in wind direction · CPC title

• F03D80/70

  Bearing or lubricating arrangements · CPC title