U.S. patent application number 12/326150 was filed with the patent office on 2010-06-03 for wind turbine with improved tower and method of assembling same.
This patent application is currently assigned to General Electric Company. Invention is credited to Sujith Sathian.
Application Number | 20100132299 12/326150 |
Document ID | / |
Family ID | 41376378 |
Filed Date | 2010-06-03 |
United States Patent
Application |
20100132299 |
Kind Code |
A1 |
Sathian; Sujith |
June 3, 2010 |
WIND TURBINE WITH IMPROVED TOWER AND METHOD OF ASSEMBLING SAME
Abstract
A wind turbine and method for assembling a wind turbine is
provided. The wind turbine is configured to stand on a foundation,
and the wind turbine assembly includes a tower and an elevated
tower foundation. The elevated tower foundation has multiple
support members having a plurality of main support members and a
plurality of bracing members. The bracing members are connected to
the main support members. The tower is mounted on the elevated
tower foundation.
Inventors: |
Sathian; Sujith;
(Simpsonville, SC) |
Correspondence
Address: |
GE ENERGY GENERAL ELECTRIC;C/O ERNEST G. CUSICK
ONE RIVER ROAD, BLD. 43, ROOM 225
SCHENECTADY
NY
12345
US
|
Assignee: |
General Electric Company
|
Family ID: |
41376378 |
Appl. No.: |
12/326150 |
Filed: |
December 2, 2008 |
Current U.S.
Class: |
52/651.01 ;
52/745.17 |
Current CPC
Class: |
E04H 12/08 20130101;
F03D 13/10 20160501; Y02E 10/72 20130101; F05B 2240/90 20130101;
Y02E 10/728 20130101 |
Class at
Publication: |
52/651.01 ;
52/745.17 |
International
Class: |
E04H 12/00 20060101
E04H012/00 |
Claims
1. A wind turbine assembly configured for standing on a foundation,
the wind turbine assembly comprising: a tower; an elevated tower
foundation having multiple support members, said multiple support
members comprising a plurality of main support members and a
plurality of bracing members connected to said main support
members; wherein, said tower is mounted on said elevated tower
foundation.
2. A wind turbine assembly in accordance with claim 1, wherein the
tower is comprised of a plurality of tower segments.
3. A wind turbine assembly in accordance with claim 1, wherein the
tower has at least one of the following shapes: tubular,
cylindrical, conical, frusto-conical, frustum, elliptical and
rectangular.
4. A wind turbine assembly in accordance with claim 1, wherein the
tower is constructed as one or more of the following: lattice, free
standing lattice, pipe, cantilevered pipe, tubular, guyed lattice
and guyed poles.
5. A wind turbine assembly in accordance with claim 1, wherein said
elevated tower foundation is configured to be about 20 to about 60
meters in height.
6. A wind turbine assembly in accordance with claim 1, wherein said
elevated tower foundation is configured to be about 20 meters or
more in height.
7. A wind turbine assembly in accordance with claim 1, wherein said
plurality of main support members are comprised of one or more of
the following group: fabricated pipes, seamless pipes, fabricated
tubes, seamless tubes, beams, and fabricated beams.
8. A wind turbine assembly in accordance with claim 7, wherein said
plurality of bracing members are comprised of one or more of the
following group: fabricated pipes, seamless pipes, fabricated
tubes, seamless tubes, beams, and fabricated beams
9. A wind turbine assembly in accordance with claim 8, wherein said
elevated tower foundation is assembled by welding or fastening said
plurality of main support members and said plurality of bracing
members at or near the location of a wind turbine.
10. A wind turbine assembly in accordance with claim 1, wherein
said tower is about 80 to about 100 meters in height, and said
elevated tower foundation is configured to be about 20 to about 60
meters in height.
11. A wind turbine assembly in accordance with claim 1, wherein
said tower is about 80 to about 100 meters in height, and said
elevated tower foundation is configured to be about 20 meters or
more in height.
12. A wind turbine assembly in accordance with claim 1, further
comprising: a foundation for supporting said elevated tower
foundation.
13. A wind turbine assembly in accordance with claim 12, wherein
said foundation is comprised of a plurality of foundation elements,
said plurality of foundation elements supporting said plurality of
main support members.
14. A method of fabrication a wind turbine tower comprising the
steps of: shipping tower components to a wind turbine location, at
least some of said tower components shipped in an un-assembled
state; assembling said tower components to form an upper tower
portion and a lower tower portion; placing said lower tower portion
on one or more foundation elements; placing said upper tower
portion on said lower tower portion.
15. The method of claim 14, wherein said upper tower portion is
comprised of about two to about four tower sections, said upper
tower portion having a height of about 80 to about 100 meters.
16. The method of claim 14, wherein said lower tower portion is
comprised of a plurality of main support members and a plurality of
bracing members connected to at least some of said main support
members, said lower tower portion having a height of about 20 to
about 60 meters.
17. The method of claim 16, wherein said main support members are
assembled by welding.
18. The method of claim 16, wherein said bracing members are
assembled by welding.
19. The method of claim 14, wherein said upper tower portion is
attached to said lower tower portion via a tower mounting flange.
Description
FIELD OF THE INVENTION
[0001] The field of this disclosure relates generally to wind
turbines, and more particularly to a tower for a wind turbine.
BACKGROUND OF THE INVENTION
[0002] Wind turbines are increasingly used for the generation of
electrical energy. A wind turbine typically comprises a
rotor-driven turbine generator mounted atop a tower constructed of
multiple tower sections that are stacked and secured together.
These sections may be cylindrical, frusto-conical or other suitable
shape, and may be generally solid, tubular, or lattice-type
sections. For example, one conventional wind turbine assembly
includes a tower in which multiple tower sections each comprise a
single-piece cylindrical or frusto-conical steel section. These
sections are joined together to reach above ground a height
sufficient to provide clearance for the turbine blades and to
support the generator at an altitude where there are sufficient
wind velocities for adequate power generation. Many towers for
utility grade wind turbines are about 80 meters in height.
[0003] The lowermost tower section (often referred to as a base
section) of the wind turbine assembly tower is secured to the
foundation (e.g., a concrete slab or other suitable foundation).
The diameter of each tower section, and in particular the base
section must be large enough in cross-section (e.g., diameter) to
withstand the aerodynamic loads produced by wind forces and
gravitational loads that are imposed by the mass of the heavy
turbine generator and the drive sections of the turbine. As wind
turbine towers have become increasingly taller, the cross-sectional
dimensions of the tower base section has created difficulties in
the ground transportation (e.g., by truck or rail) of these base
sections due to size limitations or roadways, bridges and tunnels
through which these sections must pass in route to their assembly
destination. For example, if the diameter of the tower is greater
than 4.3 meters, difficulty may be encountered during ground
transport. Manufacturing difficulties can also arise when the
thickness of the tower wall is greater than about 40 mm (e.g.,
problems with steel plate rolling and accurately obtaining plate
gap tolerance).
[0004] Wind turbine tower manufacturers have had to use other
means, such as increasing the shell thicknesses of the sections or
using guy wires, to hold smaller cross-sectioned towers in place
and support the tower against the aerodynamic and structural loads
encountered by the tower. While these measures have been helpful,
they have their limits and have not sufficiently met the need for a
wind turbine tower of greater height that is also capable of ground
transport. It has been heretofore un-economical to construct and
transport towers greater than about 80 to about 100 meters in
height.
BRIEF DESCRIPTION OF THE INVENTION
[0005] In one aspect of the present invention, a wind turbine
assembly is provided and configured to stand on a foundation. The
wind turbine assembly includes a tower and an elevated tower
foundation. The elevated tower foundation has multiple support
members having a plurality of main support members and a plurality
of bracing members. The bracing members are connected to the main
support members. The tower is mounted on the elevated tower
foundation.
[0006] In another aspect of the present invention, a method of
fabricating a wind turbine tower includes the steps of shipping
tower components to a wind turbine location. At least some of the
tower components are shipped in an un-assembled state. The next
step includes assembling the tower components to form an upper
tower portion and a lower tower portion. A placing step places the
lower tower portion on one or more foundation elements. A
subsequent step includes placing the upper tower portion on the
lower tower portion.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a schematic elevation of one embodiment of a wind
turbine assembly mounted on a foundation by a tower mount.
[0008] FIG. 2 is a perspective view of one embodiment of the tower
mount of the wind turbine assembly of FIG. 1;
[0009] FIG. 3 is a perspective view of one embodiment of an
elevated tower foundation that can be used with a conventional wind
turbine tower.
DETAILED DESCRIPTION OF THE INVENTION
[0010] Referring now to the drawings and in particular to FIG. 1,
one known wind turbine is indicated generally at 100. In this
embodiment, wind turbine assembly 100 comprises a horizontal axis
114 wind turbine. Alternatively, wind turbine assembly 100 may
comprise a vertical axis wind turbine. Wind turbine assembly 100
generally comprises a tower 102 standing upright on a suitable
foundation 104 (e.g., a concrete slab, ground surface or other
suitable foundation), and a wind turbine generator, generally
indicated at 105. Wind turbine generator 105 generally comprises a
nacelle 106 mounted on tower 102, and a rotor 108 coupled to
nacelle 106. Rotor 108 has a rotatable hub 110 and a plurality of
rotor blades 112 coupled to hub 110. Illustrated rotor 108
comprises three rotor blades 112. Alternatively, rotor 108 may have
more or less than three rotor blades 112. Blades 112 are positioned
about rotor hub 110 to facilitate rotating rotor 108 to transfer
kinetic energy from the wind into usable mechanical energy, and
subsequently, electrical energy. Blades 112 are mated to hub 110 by
coupling a blade root portion 120 to hub 110 at a plurality of load
transfer regions 122. Load transfer regions 122 have a hub load
transfer region and a blade load transfer region (both not shown in
FIG. 1). Loads induced in blades 112 are transferred to hub 110 via
load transfer regions 122.
[0011] Tower 102 is tubular, and in the illustrated embodiment it
is annular and has an internal cavity (not shown) extending
longitudinally within tower 102 from foundation 104 up to nacelle
106. Tower 102 generally comprises a plurality of individual tower
sections 124 that are connectable to each other in a stacked,
end-to-end (e.g., one on top of the other) relationship to form
tower 102. Tower sections 124 may each be of generally constant
transverse cross-sectional dimension (e.g., a constant diameter in
the illustrated embodiment in which tower sections 124 are each
generally annular), or one or more of tower sections 124 may be
frusto-conical, and/or the transverse cross-sectional dimension of
one or more of tower sections 124 may be constant but different
from that of one or more of the other tower sections--such as in a
stepped configuration in which the transverse cross-sectional
dimension of each tower section 124 decreases as the sections are
stacked toward to the top of tower 102. In addition, the present
invention can be used with towers of many shapes, including but not
limited to, tubular, cylindrical, conical, frusto-conical, frustum,
elliptical and rectangular shaped towers. The present invention can
also be used with towers constructed as lattices, free standing
lattices, cantilevered pipe, tubular and guyed lattice or poles, as
well as other suitable towers. In known towers, a highest height
obtainable has been about 80 to 100 meters.
[0012] As illustrated in FIG. 1, a known tower mount 127 is seated
on and suitably secured to foundation 104 for supporting tower 102.
The tower mount 127 can also be referred to as a foundation
mounting piece (FMP). The tower can be bolted to the FMP directly.
However, towers mounted on a FMP can add cost and result in more
expensive wind turbines. Alternatively, a wind turbine tower can be
attached directly to the base, and this type of mount can be
referred to as an anchor type design. In the anchor type the tower
base is bolted to the concrete base/foundation using anchor
bolts.
[0013] With particular reference to FIG. 2, tower mount 127 is
generally tubular in the manner of tower sections 124, and in the
illustrated embodiment it is generally annular, and has an upper
end 210, a lower end 220 (shown in FIG. 2) and a circumferential
sidewall 230 (shown in FIG. 2) extending therebetween. The terms
upper and lower are used herein with reference to the orientation
of tower 102 as illustrated in FIG. 1. Lower end 220 is suitably
configured for use in securing tower mount 127 to foundation
104.
[0014] It would be advantageous if a higher tower could be designed
to take advantage of higher mean wind speeds at higher elevations.
An improved tower is herein described that can be used alone or in
conjunction with known wind turbine towers to obtain wind turbine
towers of about 120 to about 150 meters or more in height. In
addition, the present invention can be used with towers that are
fastened to foundation mounting pieces or towers incorporating the
aforementioned anchor type design.
[0015] FIG. 3 illustrates a perspective view of an improved wind
turbine tower assembly according to aspects of the present
invention. In this embodiment a conventional tower 102 having
multiple sections 124 may be used, although not required, with
elevated foundation 300. The elevated foundation can be comprised
of tower mount or tower flange 310, pole supports 320, foundation
supports 330 and bracing members 340.
[0016] Elevated foundation may be configured to have a height of
about 20 to about 60 meters or more. Heights below or above this
range are also possible, and the specific height is guided by
location specific requirements. A conventional 80 to 100 meter
tower 102, which is a tubular wind tower structure, can be mounted
to the elevated foundation 300 via tower mount 310. The elevated
foundation 300 can be fabricated from seamless or fabricated pipes
or tubes and/or I-beams (or other beams), and may incorporate
intervening bracing members 340 (e.g., stiffeners and
cross-members) for better rigidity.
[0017] The tower mount 310 may comprise one or more elements and
can be configured similar to the tower mount 127 shown in FIG. 2.
The tower 102 can be bolted an/or welded to tower mount 310.
[0018] The pole supports 320 can be made from seamless pipes that
can be directly shipped to wind turbine sites and can be welded and
assembled on-site. In this manner, a large tower foundation 300 may
be easily shipped to remote wind turbine sites, thereby avoiding
logistical and transportation issues. Once the elevated foundation
300 is installed at the site then a conventional tower 102 can be
fastened (e.g., bolted) to the tower mount 310.
[0019] Foundation supports 330 may comprise reinforced concrete or
other suitable material. One foundation support is shown under each
pole support 320, however, it is to be understood that one or more
foundation supports could be used. For example, a single foundation
support or reinforced concrete could be configured to support all
the pole supports 320.
[0020] The bracing members 340 provide rigidity and stiffness
between pole supports 320. The bracing members can be easily
attached to the pole supports with fasteners and/or welding. For
the sake of clarity, only a few bracing members 340 are shown,
however, it is to be understood that one or more bracing members
340 may connect some or all of pole supports 320.
[0021] According to one aspect of the present invention, pole
supports may be constructed from seamless pipes of about 30 meters
in length and about 1 to 2 meters in diameter. The pipes can be
welded gas metal arc welding (GMAW), pulsed GMAW, shielded metal
arc welding (SMAW), flux cored arc welding, or any other suitable
automatic or manual welding processes. The bracing members may be
attached to the pole supports using any of the above welding
techniques or via any suitable fastener.
[0022] The present invention provides many advantages which
include, but are not limited to, use of conventional wind turbine
towers on elevated foundation, ease of transportation of tower
components, reduced cost of materials and ease of assembly.
[0023] When introducing elements of the present invention or
preferred embodiments thereof, the articles "a", "an", "the", and
"said" are intended to mean that there are one or more of the
elements. The terms "comprising", "including", and "having" are
intended to be inclusive and mean that there may be additional
elements other than the listed elements.
[0024] This written description uses examples to disclose the
invention, including the best mode, and also to enable any person
skilled in the art to practice the invention, including making and
using any devices or systems and performing any incorporated
methods. The patentable scope of the invention is defined by the
claims, and may include other examples that occur to those skilled
in the art. Such other examples are intended to be within the scope
of the claims if they have structural elements that do not differ
from the literal language of the claims, or if they include
equivalent structural elements with insubstantial differences from
the literal languages of the claims.
[0025] As various changes could be made in the above constructions
and methods without departing from the scope of the invention, it
is intended that all matter contained in the above description and
shown in the accompanying drawings shall be interpreted as
illustrative and not in a limiting sense.
* * * * *