U.S. patent application number 11/270815 was filed with the patent office on 2006-06-01 for offshore structure support and foundation for use with a wind turbine and an associated method of assembly.
Invention is credited to Rudolph A. Hall, Ralph L. Shaw.
Application Number | 20060115364 11/270815 |
Document ID | / |
Family ID | 36337280 |
Filed Date | 2006-06-01 |
United States Patent
Application |
20060115364 |
Kind Code |
A1 |
Hall; Rudolph A. ; et
al. |
June 1, 2006 |
Offshore structure support and foundation for use with a wind
turbine and an associated method of assembly
Abstract
A pile based braced caisson structural support device includes a
number of legs in is used to support a wind turbine. The wind
turbine includes a base, a turbine generator and a blade mechanism.
The legs are configured in a teepee type configuration such that
the footprint of the base is larger than the footprint of the
opposing end. This structural support can be used as a base for an
offshore platform in that the support reduces the lateral forces on
the support caused by wave action.
Inventors: |
Hall; Rudolph A.;
(Madisonville, LA) ; Shaw; Ralph L.; (New Orleans,
LA) |
Correspondence
Address: |
NIXON PEABODY, LLP
401 9TH STREET, NW
SUITE 900
WASHINGTON
DC
20004-2128
US
|
Family ID: |
36337280 |
Appl. No.: |
11/270815 |
Filed: |
November 10, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60626912 |
Nov 12, 2004 |
|
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|
Current U.S.
Class: |
416/244R |
Current CPC
Class: |
F03D 13/22 20160501;
Y02E 10/72 20130101; F03D 13/10 20160501; F05B 2240/95 20130101;
Y02E 10/727 20130101; E02D 27/425 20130101; E02B 2017/0091
20130101; F03D 13/25 20160501; E02D 27/42 20130101; Y10S 416/06
20130101; E02B 17/027 20130101 |
Class at
Publication: |
416/244.00R |
International
Class: |
F04D 29/26 20060101
F04D029/26 |
Claims
1. A wind turbine in combination with a structure support
comprising: a wind turbine comprising a base; a structure support,
said structure support further comprising at least three elements
configured in a substantially teepee shaped configuration, wherein
the at least three elements encompassing a vertical member; a first
end of the at least three elements capable of being affixed to a
structure; and a second end of the at least three elements adapted
to be in contact with a surface, wherein the at least three
elements intersect between the first end and the second end; and a
mounting flange connecting the structure support to the wind
turbine.
2. The structure of claim 1, wherein the surface is a sea floor and
the second end extends below a mudline.
3. The support of claim 1, where the at least three elements
intersect above a waterline or at a waterline.
4. The support of claim 1, wherein an angular guide maintains an
orientation at least between the at least three elements.
5. The support of claim 1, wherein the at least three elements are
offset from each other by 120.degree..
6. The support of claim 1, wherein the wind turbine further
comprises a blade mechanism.
7. The support of claim 1, wherein the structure support further
comprises a deck on which the mounting frame is fastened.
8. The support of claim 7, wherein the mounting frame includes a
foundation body and an elliptical head extending below the
deck.
9. The support of claim 1, wherein the wind turbine further
comprises a turbine element placed on the base and connecting to
the blade mechanism.
10. A method of constructing a wind turbine on a structure support
comprising: providing at least three legs in a teepee
configuration; placing an first end of the first three legs on a
surface; affixing a deck to a second end of the at least three
legs; affixing a wind turbine mounting flange to the structure;
affixing a base to the mounting frame; affixing a turbine element
to the mounting frame; and affixing a blade mechanism to the
turbine.
11. The method of claim 10, wherein the structure is located at a
position above an intersecting point of the at least three
legs.
12. The method of claim 10, wherein a guide structure is used to
orient the at least three legs.
13. The method of claim 10, further comprising: tuning the natural
period of the wind turbine so that the wind turbine and structure
operate at a predetermined frequency.
14. The method of claim 13, wherein the natural period is tuned by
adjusting the spacing between the three legs.
15. The method of claim 10, wherein the three legs are attached to
the mounting frame.
16. The method of claim 15, wherein the mounting frame includes a
foundation body and an elliptical head, and wherein the three legs
are attached to the foundation body of the elliptical head.
Description
[0001] This application claims priority to U.S. Provisional
Application No. 60/626,912, filed on Nov. 12, 2004, which is
incorporated herein by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field Of The Invention
[0003] This invention generally relates to structural supports. In
particular, this invention relates to structural supports for, for
example, wind turbines, or the like.
[0004] 2. Description Of Related Art
[0005] Conventional offshore platforms have deck legs that are
vertical or are battered outward as they extend downwards. The
conventional arrangement provides structurally efficient support
for the deck but the associated dimensions of the platform at the
water surface result in increased expense for the platform.
[0006] Wind turbines have traditionally been supported on
mono-piles when placed offshore. However, recently, efforts have
taken place to position wind turbines in deeper water
(approximately six to seven or more miles offshore) in part to
increase the aesthetics of the view from the shoreline. However,
with the movement of wind turbines further offshore, the employment
of mono-piles as the base on which wind turbines are placed has
become less cost effective.
SUMMARY OF THE INVENTION
[0007] Accordingly, the present invention is directed to a wind
turbine in combination with a structure support that provides a
sturdy and cost effective support even in deep waters. This
combination includes a wind turbine comprising a base and a blade
mechanism. The structure support further includes at least three
elements configured in a substantially teepee shaped configuration,
where the at least three elements encompassing a substantially
vertical member. A first end of the at least three elements is
capable of being affixed to a structure and a second end of the at
least three elements adapted to be in contact with a surface. The
at least three elements intersect between the first end and the
second end. The combination also includes a mounting flange
connecting the structure support to the wind turbine.
[0008] In accordance with a further embodiment of the present
invention the at least three elements intersect above a waterline
or at a waterline.
[0009] In accordance with another exemplary aspect of the present
invention, a method of constructing a wind turbine on a structure
support is disclosed. At least three legs are provided in a teepee
configuration. A first end of the first three legs are placed on a
mounting surface and a deck is affixed to a second end of the at
least three legs. A wind turbine mounting flange is affixed to the
structure and a base is affixed to the mounting frame and turbine
element is affixed to the base. A blade mechanism affixed to the
turbine element.
[0010] These and other features and advantages of this invention
are described in or are apparent from the following detailed
description of the embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The embodiments of the invention will be described in
detail, with reference to the following figures, wherein:
[0012] FIG. 1 is a view in side elevation of an offshore platform
according to the present invention;
[0013] FIG. 2 is a view in front elevation of the offshore platform
according to the present invention;
[0014] FIG. 3 is a perspective view of the offshore platform with a
wind turbine placed on a deck of the platform according to the
present invention;
[0015] FIG. 4 is a side perspective view of the offshore platform
with a wind turbine placed on the deck of the platform according to
the present invention;
[0016] FIGS. 5-18 illustrate an exemplary method of assembling the
offshore structure and wind turbine according to this
invention;
[0017] FIGS. 19-21 illustrate nnother exemplary method of
assembling the offshore structure and wind turbine according to
this invention;
[0018] FIGS. 22 and 23 illustrate another exemplary offshore
structure support foundation according to this invention.
DETAILED DESCRIPTION OF THE INVENTION
[0019] The exemplary embodiments of this invention will be
described in relation to a support structure, such as an oil and
gas platform or a platform for the placement of additional
structures, supported by three piles and a central vertical member,
such as drill pipe. However, to avoid unnecessarily obscuring the
present invention, the following description omits well-known
structures and devices that may be shown in block diagram form or
otherwise summarized. For the purposes of explanation, numerous
specific details are set forth in order to provide a thorough
understanding of the present invention. It should be appreciated
that the present invention may be practiced in a variety of ways
beyond these specific details. For example, the systems and methods
of this invention can be generally expanded and applied to support
any type of structure. Furthermore, while exemplary distances and
scales are shown in the figures, it is to be appreciated the
systems and methods of this invention can be varied to fit any
particular implementation.
[0020] FIGS. 1 and 2 show an inward battered guide offshore
platform indicated generally at 10 in which battered bracing piles
12a, 12c and 12e are arranged so as to minimize platform dimensions
at the water surface 14 while maximizing the spacing of the piles
as they extend upward from the water surface so that loads from a
deck 16 at the top of the piles are transferred directly to the
piling. For example, if three or more piles are employed to create
the structure, they could be spaced apart 120 degrees. Piles 12b
and 12d are conductor piles used in oil and gas platforms.
[0021] The platform includes a pile guide structure 18 which fits
over and is connected to a central vertical member 20 to receive
the piles 12a, 12c and 12e at the water surface. The piles extend
angularly through guides 22 of the pile guide structure in such a
manner that the distance between piles is minimized at the water
surface, but the distances between angled piles is maximized both
at the ends supporting the deck 16 as well as at the opposed end
buried below the mudline 24. The pile guide connects the piles to
act in unison to restrain lateral movement of the entire offshore
platform 10 including the central vertical member 20.
[0022] The pile guide 18 also supports appurtenances such as
ladders, boat landings, stairs, or the like, so that they can be
installed in the field as a unit, thereby, for example, reducing
installation expense for the platform. The legs 26 of the deck
structure are connected to the tops of the piles. The increased
pile spacing at the pile tops provides, for example, more
structurally efficient support for the deck, reduced structural
vibration periods for the platform and increased resistance to the
rotation that results if the deck mass is eccentric to the central
vertical member 20 than if the deck is supported by the central
member. All field connections can be made above the water surface
where structural integrity of the connections can be more easily
verified than if the connections were made below the water
surface.
[0023] Once the piles 12a, 12c and 12e are in place, and the legs
26 and deck 16 are placed on the piles then, as shown in FIGS. 3
and 4, a wind turbine 100 can be installed. FIGS. 3 and 4 show two
different perspective views of the wind turbine 100 when installed
on the deck 16 of platform 10. The wind turbine 100 comprises: a
base 125 including a lower section 110 and an upper section 120; a
turbine element 130; and a blade mechanism 150 that comprises a
rotor star 152 and individual blades 154. While the wind turbine
described herein comprises a base 125 and three individual blades
154, other types of wind turbines can also be employed with the
structure of FIG. 1, for example, in the manner described above.
For example, a wind turbine with a single base part or having a
multitude of parts that make up the base can be employed. Moreover,
the wind turbine can also include more or a lesser number of blades
as well as different types of blade mechanisms.
[0024] FIGS. 5-19 illustrate an exemplary method for assembling a
the platform 10 and wind turbine 100 in accordance with an
exemplary embodiment of this invention with, for example, a barge
boat, around a substantially vertical member 20 such as SSC 50
(Self Sustaining Caisson). In this exemplary embodiment, the SSC 50
has been installed by an oil and gas drilling rig, such as a rig
drilling an exploration well. The vertical member 20 (SSC 50) can
either be installed when the platform is assembled or alternately,
the remaining parts of the platform can be assembled around a
previously erected vertical member. This enables the platform to be
advantageously built on existing already used oil drill caissons or
mono-piles to support oil and gas wells.
[0025] In FIG. 5, the position and orientation of the legs are
determined and a lift boat 55 anchored and jacked-up relative to
the installation point of the SSC 50. Next, as illustrated in FIG.
6, the guide structure 18 is unloaded from the barge 60. Then, as
illustrated in FIG. 7, the piles 12a, 12c and 12e, are unloaded,
placed in the guide structure, and in FIG. 8, installed via the
guide structure into, for example, the ocean floor with the aid of
a pile driving hammer (e.g., a hydraulic hammer). As can be seen
from this illustration, the piles 12a, 12c and 12e intersect at a
point just above the water line. This allows, for example, the
piles and all associated connections to be made above water.
However, one would also understand that the intersection point
could also reside at or below the waterline.
[0026] In FIG. 9, the barge 60 is relocated and the deck 16 is
unloaded. In FIG. 10 the deck 16 including legs 26 are installed on
the piles. In accordance with an exemplary embodiment of the
invention, the deck can be modified to employ and support a wind
turbine 100. Specifically to support the turbine a mounted flange
can be built on the deck 16. The flange can be attached to the deck
via bolting, grouting or welding. Although as illustrated in FIG.
10, the mounting flange 200 is shown being attached to the deck
prior to placement on the legs 26, the mounting flange 200 could be
installed after the deck has been installed. FIGS. 11 and 12
provide a side view and top view of the deck 16 and mounting flange
200 when installed.
[0027] As illustrated in FIG. 13, once the mounting flange 200 is
placed and set onto the deck 16, the tower lower section 110 is
unloaded from the lift boat 55 and installed onto the mounting
frame 200. Next, as illustrated in FIG. 14, the upper section 120
of the tower is unloaded and installed onto the tower lower section
110. Once the upper section 120 of the base has been installed, as
illustrated in FIGS. 15 and 16, the turbine 130 is removed from the
lift boat and attached to the upper section 120 of the tower.
[0028] As the tower lower section 110, tower upper section 120 and
turbine 130 are installed, the blade mechanism 150 is readied for
installation. The installation of this part of the wind turbine 100
can be performed in a plurality of different ways, in accordance
with the present invention, as discussed below.
[0029] In accordance with one exemplary embodiment of the present
invention, as illustrated in FIGS. 17 and 18, the complete, blade
mechanism already fully assembled is unloaded from the lift boat 55
and attached to the turbine 130.
[0030] Alternatively, as illustrated in FIGS. 19-21, the blade
mechanism does not need to be fully assembled prior to attachment
to the turbine 130. This is advantageous for several different
reasons. The blade mechanism, if fully assembled would require
extra stowage area for transport to the assembly area. If, for
example, only two of the blades were assembled, then to the rotor
star, then the required space needed to transport the blade
mechanism is reduced. Furthermore, if the remaining blade is not
attached to the rotor star until it is already attached to the
turbine, additional monetary savings can be achieved since the
crane employed to attach the blade can be smaller. In FIG. 19, the
blade mechanism having the two blades attached to the rotor star is
raised (via a crane) and attached to the turbine (as illustrated in
FIG. 20). Finally, in FIG. 21, the remaining blade 158 is attached
to the rotor star. Again, FIGS. 3 and 4 provide a side views of the
assembled wind turbine on the offshore structure support 10.
[0031] In accordance with another exemplary aspect of the present
invention, a deck and associated mounting flange 300 is provided to
receive a wind turbine, as illustrated in FIGS. 22 and 23.
Specifically, the mounting flange 300 includes a body 310 and an
elliptical (or spherical) head 320 extending below deck 16. The
body 310 is circular and includes a deck end 312 and a head end 314
portion. A wind turbine 100 is able to be attached to the
foundation body 310 at the deck end 312 of the foundation body, via
bolting, for example. The foundation body 310 is also able to
receive legs 26 that are connected to the batter bracing piles 12a,
12c and 12e. Note that four piles are illustrated in FIG. 22.
[0032] The elliptical (or spherical) head 320 is attached to the
foundation body 310 at its deck leg connection end and enables the
turbine foundation 300 a more fatigue resistant connection at the
deck leg. For this same reason, as illustrated in FIG. 22, the ends
of the legs 26 also employ a curved surface. By making the
intersection between the foundation body 310 and the elliptical (or
spherical) head 320 as well as foundation body 310 and the
elliptical shape of the legs 26, a continuously curved intersection
is provide and a sharp corner is avoided. As a result, hot spot
stresses are reduced on the joints.
[0033] Additionally in accordance with the present embodiment
discussed with regard to FIGS. 22 and 23, the deck 16 includes
structural support elements extending from the deck end of the
turbine foundation to the edge of the deck 16. While the deck 16 in
the embodiment shown in FIG. 23 is illustrated as octagonal, one
could understand that the deck could be made to be other shapes
also, (e.g., hexagonal, rectangular, circular, or the like).
[0034] In accordance with another aspect of the present invention,
the natural period of the offshore support structure can be
adjusted to avoid the excessive vibration of the wind turbine while
operating that would result if the natural period of the support
structure was too close to matching the rotational period of the
turbine. This tuning of the natural period can be accomplished by
changing the size of the components of the support structure, by
increasing or decreasing the batter of the piles, adjusting the
spacing of the piles and/or by raising or lowering the elevations
where the piles are laterally supported. The extent and combination
of tuning measures required vary depending on the design and
operational characteristics of the wind turbine and the water
depth, meteorological and oceanographic conditions and soil
characteristics at the location.
[0035] For example, a typical three blade wind turbine is
controlled by adjusting blade pitch to make one rotation about
every 4.5 seconds in most wind conditions. Therefore, for a typical
wind turbine one of the three blades would than pass the wind
turbine support tower every 1.5 seconds. To avoid the wind turbine
rotational periods and limit potential for destructive resonance,
frequency forbidden zones are established for the natural frequency
of the entire support structure. For a typical wind turbine the
forbidden natural frequency zones could be 0.18 Hz to 0.28 Hz and
0.50 Hz to 0.80 Hz. Likewise, the target natural frequency would be
0.30 Hz to 0.33 Hz and higher order natural frequencies should be
above 0.80 Hz. If computed eignfrequencies are in a forbidden zone
tuning will be necessary. Tuning can then be accomplished in the
manner discussed above.
[0036] It is, therefore, apparent that there has been provided, in
accordance with the present invention, a support and method for
assembling a wind turbine for placement on an offshore support
structure. While this invention has been described in conjunction
with a number of illustrative embodiments, it is evident that many
alternatives, modifications, and variations would be or are
apparent to those of ordinary skill in the applicable arts.
Accordingly, the disclosure is intended to embrace all such
alternatives, modifications, equivalents and variations that are
within in the spirit and scope of this invention.
* * * * *