U.S. patent application number 13/352292 was filed with the patent office on 2013-07-18 for flange connection for a wind turbine and method of connecting parts of a wind turbine.
The applicant listed for this patent is Jay F. Leonard, Rajkumar Sivanantham, Venkata Krishna VADLAMUDI. Invention is credited to Jay F. Leonard, Rajkumar Sivanantham, Venkata Krishna VADLAMUDI.
Application Number | 20130180199 13/352292 |
Document ID | / |
Family ID | 48779006 |
Filed Date | 2013-07-18 |
United States Patent
Application |
20130180199 |
Kind Code |
A1 |
VADLAMUDI; Venkata Krishna ;
et al. |
July 18, 2013 |
FLANGE CONNECTION FOR A WIND TURBINE AND METHOD OF CONNECTING PARTS
OF A WIND TURBINE
Abstract
A flange connection for two tower sections of a wind energy
system is described. The wind energy system includes a first flange
including a first portion and a second portion, and a second flange
including a first portion and a second portion. The wind energy
system further includes a first connecting element having
substantially the shape of at least a segment of a ring and a
second connecting element having substantially the shape of at
least a segment of a ring. The first connecting element and the
second connecting element are adapted for being connected to each
other and are adapted for connecting the first portion of the first
flange with the first portion of the second flange.
Inventors: |
VADLAMUDI; Venkata Krishna;
(Bangalore, IN) ; Sivanantham; Rajkumar;
(Banglore, IN) ; Leonard; Jay F.; (Greenville,
SC) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
VADLAMUDI; Venkata Krishna
Sivanantham; Rajkumar
Leonard; Jay F. |
Bangalore
Banglore
Greenville |
SC |
IN
IN
US |
|
|
Family ID: |
48779006 |
Appl. No.: |
13/352292 |
Filed: |
January 17, 2012 |
Current U.S.
Class: |
52/651.01 ;
52/655.1 |
Current CPC
Class: |
E04H 12/085
20130101 |
Class at
Publication: |
52/651.01 ;
52/655.1 |
International
Class: |
E04H 12/00 20060101
E04H012/00; E04B 1/19 20060101 E04B001/19; E04B 1/38 20060101
E04B001/38 |
Claims
1. A flange connection for two tower sections of a wind energy
system, comprising: a) a first flange including a first portion and
a second portion; b) a second flange including a first portion and
a second portion; and, c) a first connecting element having
substantially the shape of at least a segment of a ring and a
second connecting element having substantially the shape of at
least a segment of a ring, wherein the first connecting element and
the second connecting element are adapted for being connected to
each other and are adapted for connecting the first portion of the
first flange with the first portion of the second flange.
2. The flange connection according to claim 1, wherein the first
portion and the second portion of the first and the second flange
extend in a substantially horizontal direction.
3. The flange connection according to claim 1, wherein the second
portion of the first flange and the second portion of the second
flange are adapted to be connected to each other.
4. The flange connection according to claim 1, further comprising a
third connecting element adapted for connecting the first
connecting element and the second connecting element.
5. The flange connection according to claim 1, wherein the first
connecting element s adapted for being in contact with the first
portion of the first flange and the second connecting element is
adapted for being in contact with the first portion of the second
flange in a mounted condition.
6. The flange connection according to claim 1, wherein at least one
of the group consisting of the first portion of the first flange,
the first portion of the second flange, the first connecting
element and the second connecting element has a tapered shape.
7. The flange connection according to claim 1, wherein at least one
of the first and the second connecting elements substantially have
an L-shape.
8. The flange connection according to claim 1, wherein the second
portion of the first flange and the second portion of the second
flange are adapted to be connected to each other by a third
connecting element having substantially the shape of at least a
segment of a ring and a fourth connecting element having
substantiality the shape of at least a segment of a ring.
9. The flange connection according to claim 1, wherein at least one
of the group consisting of the first connecting element and the
second connecting element substantially has the shape of a
plate.
10. The flange connection according to claim 1, wherein at least
one of the first connecting element and the second connecting
element is divided in more than one part in circumferential
direction.
11. The flange connection of claim 1, wherein the flange connection
is adapted to connect two parts of a wind energy tower to each
other.
12. The flange connection according to claim 1, wherein the first
connecting element and the second connecting clement are
substantially comprised of a substantially rigid material.
13. A wind energy system, comprising: a) a nacelle including a
rotor; b) a tower carrying the nacelle; c) a flange on at least a
part of the tower, wherein the flange includes a first portion and
a second portion extending in a substantially horizontal direction;
and, d) a connecting element having substantially the shape of at
least a segment of a ring, wherein the connecting element is
adapted for being placed on the first portion of the flange and is
adapted for securing at least a part of the tower.
14. The wind energy system according to claim 13, wherein at least
one of the group consisting of the first portion of the flange and
the connecting element provides a tapered shape.
15. The wind energy system according to claim 13, wherein the
connecting element is divided in more than one part in the
circumferential direction.
16. A tower section of a wind energy system, comprising: a) a
flange on at least a part of the tower section, wherein the flange
includes a first portion and a second portion extending in a
substantially horizontal direction; and, b) a connecting element
having substantially the shape of at least a segment of a ring,
wherein the connecting element is placed on the first portion of
the flange and is adapted for securing the tower section.
17. The tower section according to claim 16, wherein the connecting
element is divided in more than one part in circumferential
direction.
18. The tower section according to claim 16, wherein at least one
of the first portion of the flange and the connecting element
provides a tapered shape.
19. The tower section according to claim 16, further comprising a
second connecting element adapted for being placed on the second
portion of the flange and adapted for securing the tower
section.
20. The tower section according to claim 16, wherein the connecting
element is adapted for securing the tower section to at least one
of another tower section of the wind energy system, a tower base
ring, and a bearing at a tower top of the wind energy system.
Description
BACKGROUND OF THE INVENTION
[0001] The subject matter described herein relates generally to
methods and systems for flange connections, and more particularly,
to methods and systems for flange connections in a wind
turbine.
[0002] At least some known wind turbines include a tower and a
nacelle mounted on the tower. A rotor is rotatable mounted to the
nacelle and is coupled to a generator by a shaft. A plurality of
blades extends from the rotor. The blades are oriented such that
wind passing over the blades turns the rotor and rotates the shaft,
thereby driving the generator to generate electricity.
[0003] Wind turbines are placed at locations providing high wind
amounts. However, as the conditions are often rough at the wind
turbine locations and as the wind turbines become larger, the tower
of the wind turbine is subject to heavy threes. Thus, the wind
turbine tower is constructed in a stable way, including an
appropriate diameter for carrying the nacelle and withstanding the
rough conditions.
[0004] Due to the increasing size of the wind turbine tower, the
tower is segmented in several parts so as to facilitate the
transport of the wind, turbine tower to the wind turbine location.
The several parts of the wind turbine tower are mounted and
connected to each other at the wind turbine location.
[0005] When several parts of a wind turbine tower are provided and
mounted, the parts are connected by flange connections in order to
ensure the required strength of the connections. However, the
strong flange connections of the wind turbine tower parts are often
space consuming, increase the diameter of the tower segment and
consequently the transport costs.
[0006] Thus, there is a desire to provide a strong flange
connection for wind turbine parts, while taking into account the
transport costs at the same time.
BRIEF DESCRIPTION OF THE INVENTION
[0007] In one aspect, a connection for a wind energy system is
provided. Typically, the wind energy system includes a first flange
including a first portion and a second portion, and a second flange
including a first portion and a second portion. The wind energy
system may further include a first connecting element having
substantially the shape of at least a segment of a ring and a
second connecting element having substantially the shape of at
least a segment of a ring. The first connecting element and the
second connecting element may be adapted for being connected to
each other and may be adapted for connecting the first portion of
the first flange with the first portion of the second flange.
[0008] In another aspect, a wind energy system is provided.
Typically, the wind energy system includes a nacelle including a
rotor; a tower carrying the nacelle; a flange on at least a part of
the tower, wherein the flange includes a first portion and a second
portion extending in a substantially horizontal direction. Further
the wind energy system includes a connecting element having
substantially the shape of at least a segment of a ring, wherein
the connecting element is adapted for being placed on the first
portion of the flange and is adapted for securing at least a part
of the tower.
[0009] In yet another aspect, a tower section of a wind energy
system is provided. The tower section may include a flange on at
least a part of the tower section. Typically, the flange includes a
first portion and a second portion extending in a substantially
horizontal direction. Further, the tower section may include a
connecting element having substantially the shape of at least a
segment of a ring, wherein the connecting element is placed on the
first portion of the flange and is adapted for securing the tower
section.
[0010] Further aspects, advantages and features of the present
invention are apparent from the dependent claims, the description
and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] A full and enabling disclosure including the best mode
thereof, to one of ordinary skill in the art, is set forth more
particularly in the remainder of the specification, including
reference to the accompanying figures wherein:
[0012] FIG. 1 is a perspective view of an exemplary wind
turbine.
[0013] FIG. 2 is an enlarged sectional view of a portion of the
wind turbine shown in FIG. 1.
[0014] FIG. 3 is a schematic drawing of a flange connection
according to embodiments described herein.
[0015] FIG. 4 is a schematic drawing of a flange connection
according to embodiments described herein.
[0016] FIG. 5 is a schematic drawing of a flange connection
according to embodiments described herein.
[0017] FIG. 6 is a schematic drawing of a flange connection
according to embodiments described herein.
[0018] FIG. 7 is a schematic drawing of a flange connection
according to embodiments described herein.
[0019] FIG. 8 is a schematic drawing of a tower section according
to embodiments described herein.
[0020] FIG. 9 is a schematic drawing of a collar flange according
to embodiments described herein.
[0021] FIG. 10 is a schematic drawing of a flange according to
embodiments described herein.
[0022] FIG. 11 is a schematic top view of a collar flange according
to embodiments described herein.
[0023] FIG. 12 is a cross-sectional view of a wind energy tower
flange assembly according to embodiments described herein.
[0024] FIG. 13 is a schematic flow chart of a method for connecting
parts of a wind turbine according to embodiments described
herein.
DETAILED DESCRIPTION OF THE INVENTION
[0025] Reference will now be made in detail to the various
embodiments, one or more examples of which are illustrated in each
figure. Each example is provided by way of explanation and is not
meant as a limitation. For example, features illustrated or
described as part of one embodiment can be used on or in
conjunction with other embodiments to yield yet further
embodiments. It is intended that the present disclosure includes
such modifications and variations.
[0026] The embodiments described herein include a wind turbine
system that includes a flange connection having the required
strength, whilst at the same time saving transport and
manufacturing costs. More specifically, the flange assembly as
described herein provides a way to assemble a flange (such as a
T-flange) in order to overcome transportation limits. Further, the
flanges according to embodiments described herein are easy to
transport as well as easy to assemble by providing multiple split
parts across the circumference.
[0027] As used herein, the term flange is intended to be
representative of a connecting element for connecting parts. The
parts to he connected may be in the shape of a tube, a ring, a
substantially circular device or the like. According to some
embodiments, the parts to be connected may include non circular
shapes like triangular, pentagonal or multifaceted shapes. The
connecting element may he adapted to be used in wind energy
systems, such as for connecting parts of the tower of a wind energy
system. According to some embodiments, the flange may be used to
connect parts of a tower. Typically, a flange connection as used
herein may refer to a connection including a flange. For instance,
a flange connection may include two flanges to be connected to each
other. According to some embodiments, the flange connection may
include two flanges to be connected with each other and further
connecting components or elements. The flange as described herein
may be used in wind energy systems, but may also be applicable for
other technologies using flanges.
[0028] The term "at least a segment of a ring" as used herein is
intended to be representative of a ring-like device, which may be a
whole ring or a segment of a ring. Typically, the segment of the
ring may include a defined angle, which may be dependent on the
respective application. For instance, the angle of a ring segment
may be about 5.degree., about 30.degree., about 300.degree. or any
value between, above or below these examples. According to some
embodiments, having "substantially" the shape of a ring means that
a certain deviation from the ring-shape may be provided. For
instance, the device having "substantially a ring shape" may not
have a circular ring shape, but another shape, such as an elliptic
shape, a partly circular shape or the like.
[0029] Typically, the term "connecting" in this context refers to
fastening one or more parts to one or more different parts. For
instance, connecting two parts may refer to fastening or fixing
these two parts to each other. According to some embodiments,
further components, such as bolts or screws, may be used for
connecting parts together.
[0030] As used herein, the term "'blade" is intended to be
representative of any device that provides a reactive force when in
motion relative to a surrounding fluid. As used herein, the term
"wind turbine" is intended to be representative of any device that
generates rotational energy from wind energy, and more
specifically, converts the kinetic energy of wind into mechanical
energy. As used herein, the term "wind generator" is intended to be
representative of any wind turbine that generates electrical power
from rotational energy generated from wind energy, and more
specifically, converts mechanical energy converted from kinetic
energy of wind to electrical power.
[0031] FIG. 1 is a perspective view of an exemplary wind turbine
10. In the exemplary embodiment, wind turbine 10 is a
horizontal-axis wind turbine. Alternatively, wind turbine 10 may be
a vertical-axis wind turbine. In the exemplary embodiment, wind
turbine 10 includes a tower 12 that extends from a support system
14, a nacelle 16 mounted on tower 12, and a rotor 18 that is
coupled to nacelle 16. Rotor 18 includes a rotatable hub 20 and at
least one rotor blade 22 coupled to and extending outward from hub
20. In the exemplary embodiment, rotor 18 has three rotor blades
22. In an alternative embodiment, rotor 18 includes more or less
than three rotor blades 22. In the exemplary embodiment, tower 12
is fabricated from tubular steel to define a cavity (not shown in
FIG. 1) between support system 14 and nacelle 16. In an alternative
embodiment, tower 12 is any suitable type of tower having any
suitable height.
[0032] Rotor blades 22 are spaced about hub 20 to facilitate
rotating rotor 18 to enable kinetic energy to be transferred from
the wind into usable mechanical energy, and subsequently,
electrical energy. Rotor blades 22 are mated to hub 20 by coupling
a blade root portion 24 to hub 20 at a plurality of load transfer
regions 26. Load transfer regions 26 have a hub load transfer
region and a blade load transfer region (both not shown in FIG. 1).
Loads induced to rotor blades 22 are transferred to hub 20 via load
transfer regions 26.
[0033] In one embodiment, rotor blades 22 have a length ranging
from about 15 meters (m) to about 91 m. Alternatively, rotor blades
22 may have any suitable length that enables wind turbine 10 to
function as described herein. For example, other non-limiting
examples of blade lengths include 10 in or less, 20 in, 37 in, or a
length that is greater than 91 m. As wind strikes rotor blades 22
from a direction 28, rotor 18 is rotated about an axis of rotation
30. As rotor blades 22 are rotated and subjected to centrifugal
forces, rotor blades 22 are also subjected to various forces and
moments. As such, rotor blades 22 may deflect and/or rotate from a
neutral, or non-deflected, position to a deflected position.
[0034] In the exemplary embodiment, control system 36 is shown as
being centralized within nacelle 16, however, control system 36 may
be a distributed system throughout wind turbine 10, on support
system 14, within a wind farm, and/or at a remote control center.
Control system 36 includes a processor 40 configured to perform the
methods and/or steps described herein. Further, many of the other
components described herein include a processor. As used herein,
the term "processor" is not limited to integrated circuits referred
to in the art as a computer, but broadly refers to a controller, a
microcontroller, a microcomputer, a programmable logic controller
(PLC), an application specific integrated circuit, and other
programmable circuits, and these terms are used interchangeably
herein. It should be understood that a processor and/or a control
system can also include memory, input channels, and/or output
channels.
[0035] In the embodiments described herein, memory may include,
without limitation, a computer-readable medium, such as a random
access memory (RAM), and a computer-readable non-volatile medium,
such as flash memory Alternatively, a floppy disk, a compact
disc-read only memory (CD-ROM), a magneto-optical disk (MOD),
and/or a digital versatile disc (DAM) may also be used. Also, in
the embodiments described herein, input channels include, without
limitation, sensors and/or computer peripherals associated with an
operator interface, such as a mouse and a keyboard. Further, in the
exemplary embodiment, output channels may include, without
limitation, a control device, an operator interface monitor and/or
a display.
[0036] Processors described herein process information transmitted
flora a plurality of electrical and electronic devices that may
include, without limitation, sensors, actuators, compressors,
control systems, and/or monitoring devices. Such processors may be
physically located in, for example, a control system, a sensor, a
monitoring device, a desktop computer, a laptop computer, a
programmable logic controller (PLC) cabinet, and/or a distributed
control system (DCS) cabinet. RAM and storage devices store and
transfer information and instructions to be executed by the
processor(s). RAM and storage devices can also be used to store and
provide temporary variables, static (i.e., non-changing)
information and instructions, or other intermediate information to
the processors during execution of instructions by the
processor(s). Instructions that are executed may include, without
limitation, wind turbine control system control commands. The
execution of sequences of instructions is not limited to any
specific combination of hardware circuitry and software
instructions.
[0037] FIG. 2 is an enlarged sectional view of a portion of wind
turbine 10. In the exemplary embodiment, wind turbine 10 includes
nacelle 16 and hub 20 that is rotatable coupled to nacelle 16. More
specifically, hub 20 is rotatable coupled to an electric generator
42 positioned within nacelle 16 by rotor shaft 44 (sometimes
referred to as either a main shaft or a low speed shaft), a gearbox
46, a high speed shaft 48, undo coupling 50. In the exemplary
embodiment, rotor shaft 44 is disposed coaxial to longitudinal axis
116. Rotation of rotor shaft 44 rotatable drives gearbox 46 that
subsequently drives high speed shaft 48. High speed shaft 48
rotatable drives generator 42 with coupling 50 and rotation of high
speed shaft 48 facilitates production of electrical power by
generator 42. Gearbox 46 and generator 42 are supported by a
support 52 and a support 54. In the exemplary embodiment, gearbox
46 utilizes dual path geometry to drive high speed shaft 48.
Alternatively, rotor shaft 44 is coupled directly to generator 42
with coupling 50.
[0038] Nacelle 16 also includes a yaw drive mechanism 56 that may
be used to rotate nacelle 16 and hub 20 on yaw axis 38 (shown in
FIG. 1) to control the perspective of rotor blades 22 with respect
to direction 28 of the wind. Nacelle 16 also includes at least one
meteorological mast 58 that includes a wind vane and anemometer
(neither shown in FIG. 2). Mast 58 provides information to control
system 36 that may include wind direction and/or wind speed. In the
exemplary embodiment, nacelle 16 also includes a main forward
support bearing 60 and a main aft support bearing 62.
[0039] According to some embodiments, the tower of a wind turbine
may be divided in several parts so as to facilitate the transport
and mounting of the wind turbine tower. For instance, the parts or
sections being mounted to form the wind enemy tower may have a
diameter of about 4 in (such as 4.3 m) and a height in a range of
about 10 m to about 25 m (such as in a range from about 12 m to
about 24 m). The parts of a wind turbine tower may be connected by
a flange connection. Typically, T-flange constructions are proved
to be more effective arrangements compared to L-flange
arrangements. T-flanges are able to transfer larger moments than
L-flanges, which gives a benefit for larger MW rating machines.
However, T-flange assemblies providing a larger outer diameter than
L-flanges suffer from a drawback concerning transportation costs
when used in large wind turbines. A limitation of existing L-flange
design is, for instance, the number of bolts which is limited due
to space constraints. With increasing hub height and MW rating of
the wind turbine, the tower base loads tend to increase
continuously A single row of bolts, as for instance used in
L-flanges, is not adequate for high tower base moments, which is
proved by analysis. It has also been found that having an L-flange
configuration with two rows of bolts is inefficient and improves
the moment transfer capacity of the joint only marginally. Also, an
increasing number of bolts, an increasing size of the bolts and/or
an increasing width of the flange cannot deliver the desired
properties. Furthermore, increasing the tower base diameter by
dividing the tower base in the circumferential direction in order
to meet the transportation limits causes undesired side-effects.
When compared with the L-flange design, the T-flange design has a
high bearing moment due to the equal sharing of loads by both rows
of bolts, but transportation limits often prevent an integral
T-joint from being used.
[0040] The flange assembly according to embodiments described
herein concerns connecting tower sections using collar flanges. In
embodiments of the invention, the existing L-flanges are provided
with a collar of small width on the outer surface to provide a
mounting interface for a collar flange. Collar flanges having two
halves may be mounted on the respective collar of the tower
sections. Typically, the flanges of the flange assembly described
herein may be mounted to a tower section (such as welded to a tower
section) or may be a part of the tower section.
[0041] Typically, in a flange assembly according to embodiments
described herein, a collar flange is assembled to an L-flange,
whereby an outer row of bolts provided at the collar flange provide
the required clamping force. Typically, the outer row of bolts of
the collar flange together with the inner row of bolts of the
L-flange act as a T-flange. The joint connection is able to
transfer high bending moments. Typically, joints for larger MW
machines allow designing within transportation limits. The flange
connection according to embodiments described herein help in
facilitating the transport and assembly of the wind turbine parts.
Typically, an outer row of bolts are easily accessible for
maintenance since the proposed joint is a tower base ring (TBR) to
the tower door section interface.
[0042] FIG. 3 shows an embodiment of a flange connection according
to embodiments described herein. Typically, the flange connection
300 provides a first flange 310 and a second flange 320. According
to some embodiments, the first flange 310 may include a first
portion 311 and a second portion 312. Typically also the second
flange 320 may include a first portion 321 and a second portion
322. Generally, the first and the second portion 311 and 312 of the
first flange 310 and the first and the second portion 321 and 322
of the second flange 320 may extend substantially in the horizontal
direction.
[0043] The term "substantially" as used herein may mean that there
may be a certain deviation from the characteristic denoted with
"substantially." For instance, the term "substantially horizontal"
refers to a direction which may have certain deviations from the
exact horizontal position, such as a deviation of about 1.degree.
to 15.degree. of the horizontal direction. According to a further
example, the term "having substantially an L-shape" may refer to
the shape of an element in a cross-sectional view. For instance, an
element may have substantially the form of an L, when two parts of
the element are present having a certain angle between them.
Typically, the angle between the parts of the element may be
between 70.degree. and 100.degree.. Further, according to one
embodiment, one of the parts of the element denoted as having an
L-shape may be shorter than the other. According to yet a further
example, the term "having substantially the shape of a plate" may
refer to a case, where an element is formed so as to he planar.
Typically, the plate may deviate from the planar arrangement to a
certain extent.
[0044] As can be seen in FIG. 3, the flange connection 300 also
includes a first connecting element 330 and a second connecting
element 340. Typically, the first and second connecting elements
are provided in a ring-like shape or at least as a segment of a
ring-like shape, as will be explained in detail below.
[0045] According to some embodiments, which can be combined with
other embodiments described herein, the first connecting element
and the second connecting element may be adapted to he connected to
each other. Typically, the first connecting element and the second
connecting element may be adapted to connect the first portion of
the first flange to the first portion of the second flange.
[0046] Typically, the first portion of a flange as described herein
may also be referred to as a collar of the flange. Further,
according to some embodiments, the first and the second connecting
element as described herein may also be denoted as collar
flanges.
[0047] Typically, the flange connection according to embodiments
described herein is assembled so as to obey transportation limits.
According to some embodiments, an L-flange is assembled into a
T-flange by providing a collar extension to the L-flange, wherein
the extension of the collar in the horizontal direction is smaller
than the extension of a T-flange in the respective direction. For
instance, the extension of the collar of the flange in the
horizontal direction may typically range from about 50 mm to about
200 mm, more typically from about 70 mm to about 150 mm, and even
more typically from about 90 mm to about 110 mm. According to one
embodiment, which can be combined with other embodiments described
herein, the extension of the collar of the flange in the horizontal
direction may be about 100 mm.
[0048] According to some embodiments, the connecting elements, such
as collar flanges described herein, may be made from a
substantially rigid or non-elastic material, such as steel,
aluminum and like metallic materials, but also composite materials
or the like.
[0049] In an embodiment described herein, the first and/or second
connecting element (such as a collar flanges) may be split into
multiple flat plates to reduce manufacturing costs. This could be
achieved by either using one flat plate as one of the connecting
elements and extending the other connecting element (as described
in detail referring to FIG, 4), or using two flat plates and one
circular ring to form an integral flange (as described in detail
referring to FIG. 5).
[0050] FIG. 4 shows an embodiment of a flange connection. The
flange connection 400 provides a first flange 410 and a second
flange 420. Typically, the first flange 410 has a first portion 411
and a second portion 412. Also, the second flange 420 typically has
a first portion 421 and a second portion 422. According to some
embodiments, a first connecting element 430 and a second connecting
element 440 are provided. In the embodiments of FIG. 4, the first
connecting element 430 has the shape of a ring-like plate and the
second connecting element 440 is provided as a collar flange having
substantially an L-shape.
[0051] Typically, the first and second connecting element 430 and
440 are adapted to be connected to each other. In the example shown
in FIG. 4, the first connecting element 430 is a plate extending in
a substantially horizontal direction beyond the first portion 411
(such as the collar) of the first flange 410. The second connecting
element 440 of the example shown in FIG. 4 substantially has an
L-shape, which extends in a vertical direction along the first
portions 411 and 421 of the first and second flanges 410 and 420.
The extension of the second connecting element 440 of the flange
connection 400 in the horizontal direction corresponds to the
extension of the first connecting element 430. Typically, the
extension of the second connecting element 440 in the horizontal
direction exceeds the extension of the first portion 421 of the
second flange 420 in the horizontal direction.
[0052] FIG. 5 shows a flange connection 500 according to some
embodiments described herein. Typically, the flange connection 500
provides a first flange 510 and a second flange 520. Each of the
first and the second flanges 510, 520 may have a first portion 511,
521 and a second portion 512, 522, respectively. According to some
embodiments, the flange connection 500 may have a first connecting
element 530, a second connecting element 540 and a third connecting
element 550. Typically, the three connecting elements 530, 540, and
550 are adapted to be connected to each other. According to
embodiments described herein, the three connecting elements 530,
540, and 550 are adapted to connect the first portion 511 of the
first flange 510 and the first portion 521 of the second flange
520. Typically, the first portions of the first and second flanges
are formed as a collar extending in the horizontal direction.
[0053] Typically, two of the three connecting elements shown n FIG.
5 may be formed as a plate. In the example shown in FIG. 5,
connecting elements 530 and 540 have a plate-like shape. Typically,
the third connecting element 550 may have the shape of a ring
extending around the circumference of the first and second flange,
in particular around the collar of the flange.
[0054] According to some embodiments, the flanges of the flange
connection may be connected at the second portion of the flanges
too. As can exemplarily be seen in FIGS. 3 to 5, the second
portions 312 and 322, 412 and 422 and 512 and 522 are connected by
a fastening device, such as a screw, a bolt, or the like, in the
examples of FIGS. 3 to 5, the fastening devices are shown as screws
360, 460 and 560, respectively.
[0055] Typically bolted joints may be used to connect the
connecting elements (such as collar flanges) according to
embodiments described herein, to provide the required clamping
force for integrating the joint.
[0056] In another embodiment, the configuration can also be applied
to an internal tower flange if additional space is required inside
the tower shell, for instance in the case, where the down tower
electrical system is assembled within the tower in pre-assembled
power modules (PPM). According to some embodiments, which can be
combined with other embodiments described herein, the second
portion of the first and the second flange may be connected by
connecting elements, the connecting elements being similar to those
used for connecting the first portions of the flanges. Such an
example is shown in FIG. 6. Typically, the flange connection 600
includes a first flange 610 and a second flange 620. According to
some embodiments, the first flange 610 may have a first portion 611
and a second portion 612. Typically, the second flange 620 may also
have a first portion 621 and a second portion 622.
[0057] In the embodiment shown in FIG. 6, the first portion 611 of
the first flange 610 and the first portion 621 of the second flange
620 are connected by connecting elements 630 and 640. Typically,
the connecting elements provide a ring-like shape or a segment of a
ring-like shape and are adapted to be connected to each other
(e,g., by fastening devices). Further, the connecting elements may
be adapted to connect the first portions of the flanges with each
other. Typically, the second portion 612 of the first flange 610
and the second portion 622 of the second flange 620 are connected
by connecting elements 650 and 660. Typically; the connecting
elements are adapted to be connected to each other by fastening
devices) and are adapted to connect the second portions of the
flanges with each other. In the example of the flange connection of
FIG. 6, the second portions 612 and 622 of the first and second
flange 610 and 620 may have approximately the same extension in the
horizontal direction as the first portions 611 and 621 of the first
and second flanges. For instance, the second portion 612 or 622 may
extend substantially in the horizontal direction from about 50 mm
to about 200 mm, more typically from about 70 mm to about 150 mm,
and even more typically from about 90 mm to about 110 mm. According
to one embodiment, which can be combined with other embodiments
described herein the extension of the second portion of the flange
being provided as a collar in horizontal direction may be about 100
mm.
[0058] FIG. 7 shows an embodiment of a flange connection 740,
wherein each of the first portions 741 and 751 of the first flange
743 and the second flange 744 are connected by a connecting element
770 formed in a one-piece design. Also the second portions 742 and
752 of the first flange 743 and the second flange 744 are connected
by a connecting element 750 formed in a one-piece design. It is to
be understood that the term "one-piece design" refers to a design
of a connecting element, where the connecting element covers the
height of the first portions of both the first and the second
flanges. Typically, the connecting element 750 and 770 may be
fastened by fastening devices 780 in a substantially horizontal
direction.
[0059] According to some embodiments, the flange connection
described herein may also be denoted as a bore-free flange
connection or at least a partly bore-free flange connections. For
instance, the first portion extending outwardly in the radial
direction does not provide bores for fastening the flange, as can
exemplarily be seen in FIGS. 3 to 5. In the examples shown in FIGS.
6 and 7, the first portion as well as the second portion of the
flange may be described as being bore-free, being adapted for being
connected by connecting elements.
[0060] FIG. 8 shows an example of a tower section 840 of a wind
energy system. According to some embodiments, the tower section
includes a flange, which provides a first portion 851 and a second
portion 852. Typically, the first portion 851 and the second
portion 852 extend in a substantially horizontal direction.
Further, the tower section includes a connecting element 870 having
substantially the shape of at least a segment of a ring, as will be
explained in detail below. Typically, the connecting element 870 is
placed on the first portion 851 of the flange and is adapted for
securing the tower section 840. The connecting element may be
fastened by fastening devices 860, which may be bolts, screws, or
the like.
[0061] According to some embodiments, the connecting element 870 is
divided in more than one part in circumferential direction, which
is shown and explained in detail with respect to FIG. 11. Further,
the tower section may include a second connecting element, which is
placed on the second portion 852 of the flange and which is adapted
for securing the tower section 840. According to some embodiments,
the connecting e lent 870 may be adapted for securing the tower
section 840 to another tower section of the wind energy system, a
tower base ring, and a bearing at a tower top of the wind energy
system, such as a yaw bearing at the top of the tower of the wind
energy system.
[0062] Generally, the ratio between the extension of the first
portion in the horizontal direction and the second portion in the
horizontal direction may be about 1:1, 1:2, or up to 1:5. For
instance, the embodiments shown in FIGS. 6 and 7 show a ratio of
the extension of the first portion to the extension of the second
portion in horizontal direction of substantially 1:1. Other
embodiments (such as embodiments shown in FIGS. 3 to 5) may provide
a ratio of the extension of the first portion to the extension of
the second portion in horizontal direction of exemplarily 1:2, 1:3,
1:4 or 1:5. According to further embodiments and dependent on the
design of the flange, the ratio of the extension of the first
portion to the extension of the second portion in horizontal
direction of substantially may exceed the ration of 1:5.
[0063] In FIG. 9, a schematic cross-sectional view of an embodiment
of a connecting element 700 (such as a collar flange) is shown,
which can be combined with other embodiments described herein and
can be used in every example of a flange connection described
herein. The connecting element 700 of FIG. 9 is formed as a collar
flange and substantially provides an L-like shape. The collar
flange 700 may include a substantially vertical portion 710 and a
substantially horizontal portion 720. Typically, the vertical
portion 710 may include a contacting side 715 for contacting a
vertical portion of a first or second portion of a flange. The
horizontal portion 720 may include a contacting side 725 for
contacting a horizontal portion of a first or second portion of a
flange. According to sonic embodiments, the collar flange 700 is
equipped with a slope to provide a dovetail shape for improving the
clamping force between the first or second portion of a flange and
the collar flange. The slope is indicated by angle 730 in FIG. 9.
Typically, the angle 730 of FIG. 9 is measured from the horizontal
direction.
[0064] In addition, also the collar of a flange, such as the first
or second portion of a flange may be provided with a slope for
improving the clamping force between the first or second portion of
a flange and the connecting element. FIG. 10 shows a schematic
cross-sectional view of an example of a flange having a first
portion in a dovetail shape. The flange 800 of FIG. 10 includes a
first portion 810 and a second portion 820 extending substantially
in the horizontal direction. The first portion 810 provides a slope
at the contacting face 815, at which a connecting element may
contact the first portion 810. Typically, the slope is indicated by
angle 830 in FIG. 10.
[0065] Typically, the angle provided on one or more components of
the flange connection or flange assembly for forming the tapered
shape or a slope may be between about 0.5.degree. to about
7.degree., more typically between about 1.degree. and 5.degree.,
and even more typically between about 2.degree. and 4.degree..
According to one embodiment, which can be combined with other
embodiments described herein, the angle for forming the tapered
shape may be about 2.degree..
[0066] According to some embodiments, both the flange and the
connecting element may provide a slope in order to improve the
clamping force between them. It may also be possible to provide the
first and/or second portions of the flange with a slope. Typically,
either component of a flange connection as described herein may be
equipped with a slope on a contacting face for improving the
clamping force. In particular, the embodiments described with
respect to FIGS. 3 to 8 may provide a connecting clement and/or a
portion of the flange with a slope. It is also to be understood
that components of the flange connection having a slope are also
referred to as extending substantially in a horizontal direction,
although the slope deviates from the horizontal direction.
[0067] According to some embodiments, which can be combined with
other embodiments described herein, the connecting elements (such
as the collar flange) can be split into multiple numbers of parts
to make it as a split flange for easy connection and
transportation. In that way, collar flanges can typically be
transported in multiple parts and are within transportation limits.
The collar flange can be assembled at the construction site of the
wind turbine with minimum equipment.
[0068] For instance, FIG. 11 shows an embodiment of a connecting
element 900 (such as a first or second connecting clement described
above) being provided including three segments 910, 920, and 930 of
a ring-like shape. Each of the segments 910, 920, and 930 may
enclose the same angle, as shown in FIG. 11. However, according to
further embodiments, the angles of the segments may vary.
Typically, the connecting element 900 is equipped with holes 940
adapted for accommodating fastening devices.
[0069] In FIG. 11, three segments are shown. However, it is to be
understood that the number of segments is not limited. According to
some embodiments, the connecting element includes only one part.
According to further embodiments, the connecting element may
include 3, 5, 10, or even more than 10 segments. According to yet
further embodiments, the connecting element may include one segment
for one fastening device.
[0070] Typically, assembled together the segments build a whole
ring. According to other embodiments, the segments cover only a
part of a 360.degree. ring.
[0071] An example of an arrangement, wherein the connecting element
covers only a part of the circumference of the wind energy tower,
is shown in FIG. 12, FIG. 12 shows a cross-sectional view of an
arrangement 1000 including a wind energy tower 1010 being equipped
with a T-flange 1020. The T-flange may be equipped with holes 1025
or the like for accommodating fastening devices. The T-flange 1020
and the holes 1025 may be used to connect the flange to another
flange.
[0072] Typically, the T-flange 1020 is only partly provided around
the circumference of the tower 1010. For instance, the T-flange
1010 may have flattened portions 1030. The flattened portions 1030
may help complying with transportation or packaging limits.
According to some embodiments, the flattened portions 1030 ensure
that the arrangement 1000 does not exceed a shipping limit. The
height 1040 of the arrangement 1000 is thus adapted to comply with
shipping limits. However, in order to provide the required
strength, although the T-flange covers only a part of the whole
circumference of the tower 1010, connecting element 1050 and 1055
may be provided. Typically, the connecting elements 1050, 1055 may
be connecting elements as described above and may be provided on a
first portion 1060 of the T-flange, such as a collar 1060. The
connecting elements 1050, 1055 are exemplarily shown with a curved
shape at one side, however, it is to be understood that the shape
of the connecting element may also be flat shaped without
curvature.
[0073] The embodiment shown in FIG. 12 may also be denoted as a
flange having lateral cut-outs for receiving the connecting
elements. For instance, the flange may be adapted (e.g., by
providing bores) for being fastened by fastening devices (such as
screws, bolts, or the like) at a defined portion of the
circumference and may be adapted for being fastened at other
portions of the circumference (such as the cut-out portions) by
connecting elements as described above.
[0074] According to some embodiments, the described flange
assemblies may also be used to connect a wind energy tower to the
ground. In this case, one flange and one connecting element may be
used to fix the tower to respective components in the ground.
[0075] Typically, embodiments described herein refer to a method
for connecting parts of a wind energy system. FIG. 13 shows a flow
chart representing an example of such a method 1100. According to
embodiments described herein, the wind energy system typically
includes a first flange and a second flange. The first and the
second flange each include a first portion and a second portion.
The first portion may be a collar extending substantially in the
horizontal direction. Typically, the first flange and the second
flange may be flanges as described above with respect to FIGS. 3 to
8, 10, and 12.
[0076] According to some embodiments, in block 1110, a first
connecting element is placed on the first portion of the first
flange. Typically, the first connecting element has substantially
the shape of at least a segment of a ring. In block 1120, a second
connecting element is placed on the first portion of the second
flange.
[0077] Typically the first connecting element and the second
connecting element may have a ring-like shape or be a segment of a
ring-like shape. Further, the first connecting element may be
provided in several parts. For instance, in the case where the
connecting element is provided as a segment of a ring-like shape,
the connecting element may be described as including more than one
segment.
[0078] Block 1130 refers to connecting the first connecting element
and the second connecting element to connect the first portion of
the first flange with the first portion of the second flange.
Typically, fastening devices may be used to connect the first and
second connecting element with each other.
[0079] The method according to embodiments described herein may be
used for operating a wind energy system as described above. Also,
the method may be used to connect parts of a wind energy system
using the above described examples of flange connections and
assemblies. For instance, the method for operating a wind energy
system according to embodiments described herein may further
include providing a third connecting element, which may help
connecting the first and the second connecting elements.
[0080] Typically, the first and the second flanges may additionally
be connected through the second portions of the flanges. For
instance, fastening devices, such as screws, may be used to connect
the second portion of the first flange with the second portion of
the second flange.
[0081] According to sonic embodiments, the second portion of the
first flange may be connected with the second portion of the second
flange using further connecting elements, such as a third and
fourth connecting element. Typically, the third and fourth
connecting elements for connecting the second portion of the first
flange with the second portion of the second flange may be of the
same design as the first and second connecting elements. In
particular, they may be designed as described above with respect to
FIGS. 3 to 9 and 11 to 13.
[0082] Embodiments described herein are also applicable for a
reverse taper tower door section keeping the collar within
transportation limits.
[0083] The above-described systems and methods facilitate the
transportation and assembly of wind turbine parts or components.
More specifically, the flange connection according to embodiments
described above allows for complying with transportation limits,
thereby decreasing costs for transportation and, at the same time,
provides a reliable and exact connection of wind turbine parts,
such as parts of a wind turbine tower.
[0084] Exemplary embodiments of systems and methods for a flange
connection and a flange assembly are described above in detail. The
systems and methods are not limited to the specific embodiments
described herein, but rather components of the systems and/or steps
of the methods may be utilized independently and separately from
other components and/or steps described herein. For example, the
flange connection described herein may be used in further
applications, other than just those concerning connecting parts of
a wind turbine, and are not limited to practice with only the wind
turbine systems as described herein. Rather, the exemplary
embodiment can be implemented and utilized in connection with many
other rotor blade applications.
[0085] Although specific features of various embodiments of the
invention may be shown in some drawings and not in others, this is
for convenience only. In accordance with the principles of the
invention, any feature of a drawing may be referenced and/or
claimed in combination with any feature of any other drawing.
[0086] 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. While various specific embodiments have been disclosed in
the foregoing, those skilled in the art will recognize that the
spirit and scope of the claims allows for equally effective
modifications. Especially, mutually non-exclusive features of the
embodiments described above may be combined with each other. 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 language
of the claims.
* * * * *