Wind turbine blades with layered, multi-component spars, and associated systems and methods

Patent metadata

Field	Value
Publication number	US-9470205-B2
Application number	US-201313802590-A
Country	US
Kind code	B2
Filing date	Mar 13, 2013
Priority date	Mar 13, 2013
Publication date	Oct 18, 2016
Grant date	Oct 18, 2016

Abstract

Wind turbine blades with layered, multi-component spars, and associated systems and methods are disclosed. A wind turbine blade system in accordance with a particular embodiment includes a first blade segment having a first spar element that includes first planks having a first thickness and a first plank composition, and a second blade segment having a second spar element that includes second planks having a second thickness and a second plank composition different than the first plank composition. The second blade segment is joined to the first blade segment at a joint, and, in particular embodiments, an overall product of thickness and elastic modulus of the first planks is approximately equal to an overall product of thickness and elastic modulus for the second planks.

First claim

We claim:

1. A wind turbine blade system, comprising:
a first blade segment having a first spar element that includes first planks having a first thickness and a first plank composition; and
a second blade segment having a second spar element that includes second planks having a second thickness and a second plank composition different than the first plank composition, the second blade segment being joined to the first blade segment at a joint, wherein an overall product of thickness and elastic modulus of the first planks is equal or approximately equal to an overall product of thickness and elastic modulus for the second planks.

2. The system of claim 1 wherein an individual second plank includes multiple layers, and wherein the overall product of thickness and elastic modulus for the second plank is equal to the sum of the product of thickness and elastic modulus for each layer of the second plank.

3. The system of claim 1 wherein individual first planks are interleaved with individual second planks at the joint.

4. A wind turbine blade system, comprising:
first and second blade segments positioned at different locations along a longitudinal axis and joined together to form at least a portion of a wind turbine blade, the first blade segment including a first spar element and the second blade segment including a second spar element; wherein
the second spar element is elongated along the longitudinal axis and includes multiple second planks, with individual second planks including at least one first layer having a first composition, at least one second layer having a second composition different than the first composition, and an adhesive between the first and second layers, the adhesive having an adhesive composition different than the first and second compositions; and wherein
the first spar element is elongated along the longitudinal axis and includes multiple first planks, with individual first planks including at least one third layer having a third composition different than the first and second compositions: further wherein;
ends of the first planks and the second planks are interleaved to form a joint between the first and second spar elements:
at the joint, a thickness of an individual first plank is T 1 , a thickness of the first layer is T 2 a and a thickness of the second layer is T 2 b , with T 1 approximately equal to T 2 a +T 2 b;
an elastic modulus of the first composition is E 2 a , an elastic modulus of the second composition is E 2 b , and an elastic modulus of the third composition is E 1 ; and (E 1 ×T 1 ) is approximately equal to (E 2 a ×T 2 a )+(E 2 b ×T 2 b ).

5. The system of claim 4 wherein the first and second spar elements each include a spar cap.

6. The system of claim 4 wherein the first composition includes fiberglass and the second composition includes carbon fiber.

7. The system of claim 4 wherein at least one of the individual planks of the second spar element has an end and an intermediate location positioned outwardly along the longitudinal axis from the end, and wherein a thickness of at least one of the first and second layers of the at least one second plank is greater at the end than at the intermediate location.

8. The system of claim 4 wherein E 2 b higher than E 2 .

9. The system of claim 4 wherein the first and second individual planks have approximately the same thickness.

10. A wind turbine blade system, comprising:
a first blade segment having a longitudinal axis, the first blade segment including at least one first spar element that is elongated along the longitudinal axis, the at least one first spar element including multiple first planks, with individual first planks having a first thickness T 1 and a first elastic modulus E 1 ; and
a second blade segment having at least one second spar element joined to the at least one first spar element at a spar joint and extending along the longitudinal axis, the at least one second spar element including multiple second planks joined to corresponding first planks at the spar joint, with individual second planks having a second thickness T 2 and including at least one first layer having a first layer thickness T 2 a and first composition with an elastic modulus of E 2 a , and at least one second layer having a second layer thickness T 2 b and a second composition different than the first composition with an elastic modulus of E 2 b , and wherein
(E 1 ×T 1 ) is equal or approximately equal to (E 2 a ×T 2 a )+(E 2 b ×T 2 b ).

11. The system of claim 10 wherein the first planks include unidirectional fiberglass, the first composition includes biaxial fiberglass, and the second composition includes unidirectional carbon fibers.

12. The system of claim 10 wherein the first thickness T 2 a of an individual first layer diminishes in a longitudinal direction outwardly away from the joint.

13. The system of claim 10 , wherein the second blade segment has a first end inboard along the longitudinal axis from a second end and wherein the first layers terminate inboard of the second end.

14. A wind turbine blade, comprising:
a first blade segment having a first spar cap portion, the first spar cap portion including a plurality of laminated first planks, wherein individual first planks are formed from unidirectional fiberglass, have a first thickness, and terminate at different longitudinal locations to form a first end portion having a plurality of first projections and first recesses, with individual first projections alternating with individual first recesses along a thickness axis; and
a second blade segment having a second spar cap portion, the second spar cap portion including a plurality of laminated second planks, wherein individual second planks are formed from biaxial fiberglass strips attached to carbon strips, and terminate at different longitudinal locations to form a plurality of second projections and second recesses, with individual second projections alternating with individual second recesses along the thickness axis;
wherein the individual second planks have a second thickness the same or approximately the same as the first thickness at the corresponding second projections, and have a third thickness less than the second thickness at an intermediate location spaced apart from the corresponding second projections;
wherein a thickness of the biaxial fiberglass strips decreases to zero at the intermediate location; and
wherein individual second projections are received in corresponding first recesses, and individual first projections are received in corresponding second recesses, to join the first spar cap portion to the second spar cap portion: further wherein;
(E 1 ×T 1 is equal or approximately equal to (E 2 a ×T 2 a )+(E 2 b ×T 2 b ), where;
E 1 =the elastic modulus of the unidirectional fiberglass;
E 2 a =the elastic modulus of the biaxial fiberglass;
E 2 b =the elastic modulus of the carbon;
T 1 =the thickness of the first planks;
T 2 a =the thickness of the biaxial fiberglass strips; and
T 2 b =the thickness of the carbon strips.

15. A method for manufacturing a wind turbine blade system, comprising:
selecting a first spar element of a first blade segment to include first planks having a first thickness and a first plank composition;
selecting a second spar element of a second blade segment to include second planks having a second thickness and a second plank composition different than the first plank composition;
sizing the first planks to join with the second planks;
selecting the first and second thicknesses, an

Assignees

• Liu Qiang
• Baker Myles L
• Vestas Wind Sys As

Inventors

• Liu Qiang
• Baker Myles L

Classifications

• F05B2240/302

  Segmented or sectional blades · CPC title

• B29C66/1248

  Interpenetrating groove joints (interpenetrating fingered joints B29C66/139) · CPC title

• B29C65/48

  using adhesives {, i.e. using supplementary joining material; solvent bonding} · CPC title

• B29C70/52

  Pultrusion, i.e. forming and compressing by continuously pulling through a die · CPC title

• F03D1/0675 Primary

  of the blades · CPC title