BACKGROUND OF THE INVENTION
The subject matter disclosed herein relates generally to modular
towers, and more specifically, to assembling sections of a modular tower.
Modular towers structures are often used as bases to support structures,
such as wind turbine towers, mobile phone towers, and power poles. Because of their
size, such towers are often constructed on site, as the towers themselves are much
larger than is practically transportable. Components used with such towers are often
assembled off-site. Similar to the tower itself, transportation logistics generally limit
the storage size and/or weight of such components.
Tower height is at least partially limited by the dimensions of the base
of the tower. As such, a taller tower requires a correspondingly larger base to
adequately support the tower structure. To enhance the overall structural integrity and
to reduce on-site assembly time, it is generally desirable to assemble the components
of the modular tower in as few pieces as possible. However, due to transportation
limitations, the overall size of components and sections is limited. As such, the height
of the tower may be limited by the size of the unitary components that can be used in
light of transportation limitations.
BRIEF DESCRIPTION OF THE INVENTION
In one aspect, a tower assembly for use with a modular tower is
provided. The tower assembly comprises a plurality of assembly panels each
comprising a pair of opposing circumferential edges, and, a plurality of connectors for
use in coupling adjacent assembly panels of the plurality of assembly panels to one
another, each connector of the plurality of coimectors comprising an outer flange, an
inner flange, and a spacer extending therebetween, the outer flange is spaced a
distance from the irmer flange such that a first slot and a second slot are defined
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between the outer and inner flanges, each of the first and the second slots is sized to
receive one of the assembly panel circumferential edges therein to enable the adjacent
assembly panels to be coupled to one another.
In another aspect, a method for assembling a modular tower is
provided. The method comprises providing at least one cormector each including a
first flange, a second flange, and a spacer extending therebetween, providing a
plurality of section panels each including a first circumferential edge and a second
circumferential edge, inserting the first circumferential edge of a first of the plurality
of section panels into a first slot of the connector, wherein the first slot is defined
between the first flange and the second flange, inserting the second circumferential
edge of a second of the plurality of section panels into a second slot of the connector,
wherein the second slot is defined between the first flange and the second flange, and,
coupling the connector to the first and second section panels.
In yet another aspect, a modular tower is provided. The modular tower
comprises at least one lower tower section comprising a plurality of section panels
each comprising a pair of opposing circumferential edges, and, a plurality of
connectors for use in coupling adjacent section panels of the plurality of section
panels to one another, each of the connectors comprising an outer flange, an inner
flange, and a spacer extending therebetween, the outer flange is spaced a distance
from the inner flange such that a first slot and a second slot are defined between the
outer and inner flanges, each of the first and the second slots is sized to receive one of
the section panel circumferential edges therein to enable the adjacent section panels to
be coupled together. The modular tower fiirther comprises at least one upper tower
section coupled to the lower section.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a schematic view of an exemplary wind turbine.
Fig. 2 is a partial sectional view of an exemplary nacelle used
with the wind turbine shown in Fig. 1.
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Fig. 3 is a perspective view of an exemplary tower section that
may be used with the wind turbine shown in Fig. 1.
Fig. 4 is an enlarged perspective view of a portion of the tower
section shown in Fig. 3 and taken along area 4.
Fig. 5 is a perspective cross-sectional view of a portion of
tower sections that may be used with the wind turbine shown in Fig. 1.
Fig. 6 is a perspective cross-sectional view of a portion of
tower sections that may be used with the wind turbine shown in Fig. 1.
Fig. 7 is a perspective view of an exemplary section panel that
may be used with the wind turbine shown in Fig. 1.
Fig. 8 is a perspective view of an exemplary tower section that
may be used with the wind turbine shown in Fig. 1.
Fig. 9 is a plan view of the tower section shown in Fig. 8.Fig.
10 is an enlarged view of a portion of the tower section shown
in Fig. 8.
DETAILED DESCRIPTION OF THE INVENTION
The methods and modular tower components described herein
facilitate construction of a modular tower. Specifically, the modular tower
components and methods described herein enable construction of tower sections that
are larger than unitary tower sections that are limited in size by transportation
limitations. Using larger modular tower sections, structurally-sound towers having
higher hub heights can be constructed. Moreover, spacer elements described herein
facilitate aligning adjacent section panels together during construction, and thus,
increase the structural integrity of the assembled tower. Moreover the flanges
described herein that are used to connect adjacent tower sections together, facilitate
reducing hoop stresses induced to the tower components.
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Fig. 1 is a schematic view of an exemplary wind turbine 100. In the
exemplary embodiment, wind turbine 100 is a horizontal-axis wind turbine.
Alternatively, wind turbine 100 may be a vertical-axis wind turbine. In the exemplary
embodiment, wind turbine 100 includes a tower 102 extending from and coupled to a
supporting surface 104. Tower 102 may be coupled to surface 104 with anchor bolts
or via a foundation mounting piece (neither shown), for example. A nacelle 106 is
coupled to tower 102, and a rotor 108 is coupled to nacelle 106. Rotor 108 includes a
rotatable hub 110 and a plurality of rotor blades 112 coupled to hub 110. In the
exemplary embodiment, rotor 108 includes three rotor blades 112. Alternatively,
rotor 108 may have any suitable number of rotor blades 112 that enables wind turbine
100 to function as described herein. Tower 102 may have any suitable height and/or
construction that enables wind turbine 100 to function as described herein.
Rotor blades 112 are spaced about hub 110 to facilitate rotating rotor
108, thereby transferring kinetic energy from wind 114 into usable mechanical
energy, and subsequently, electrical energy. Rotor 108 and nacelle 106 are rotated
about tower 102 on a yaw axis 116 to control a perspective of rotor blades 112 with
respect to a direction of wind 114. Rotor blades 112 are mated to hub 110 by
coupling a rotor blade root portion 118 to hub 110 at a plurality of load transfer
regions 120. Load transfer regions 120 each have a hub load transfer region and a
rotor blade load transfer region (both not shown in Fig. 1). Loads induced to rotor
blades 112 are transferred to hub 110 via load transfer regions 120. Each rotor blade
112 also includes a rotor blade tip portion 122.
In the exemplary embodiment, rotor blades 112 have a length of
between approximately 30 meters (m) (99 feet (ft)) and approximately 120 m (394 ft).
Alternatively, rotor blades 112 may have any suitable length that enables wind turbine
100 to function as described herein. For example, rotor blades 112 may have a
suitable length less than 30 m or greater than 120 m. As wind 114 contacts rotor
blade 112, lift forces are induced to rotor blade 112 and rotation of rotor 108 about an
axis of rotation 124 is induced as rotor blade tip portion 122 is accelerated.
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A pitch angle (not shown) of rotor blades 112, i.e., an angle that
determines the perspective of rotor blade 112 with respect to the direction of wind
114, may be changed by a pitch assembly (not shown in Fig. 1). More specifically,
increasing a pitch angle of rotor blade 112 decreases an amount of rotor blade surface
area 126 exposed to wind 114 and, conversely, decreasing a pitch angle of rotor blade
112 increases an amount of rotor blade surface area 126 exposed to wind 114. The
pitch angles of rotor blades 112 are adjusted about a pitch axis 128 at each rotor blade
112. In the exemplary embodiment, the pitch angles of rotor blades 112 are
controlled individually.
Fig. 2 is a partial sectional view of nacelle 106 used with wind turbine
100. In the exemplary embodiment, various components of wind turbine 100 are
housed in nacelle 106. For example, in the exemplary embodiment, nacelle 106
includes pitch assemblies 130. Each pitch assembly 130 is coupled to an associated
rotor blade 112 (shown in Fig. 1), and modulates a pitch of an associated rotor blade
112 about pitch axis 128. In the exemplary embodiment, each pitch assembly 130
includes at least one pitch drive motor 131.
Moreover, in the exemplary embodiment, rotor 108 is rotatably
coupled to an electric generator 132 positioned within nacelle 106 via a rotor shaft
134 (sometimes referred to as either a main shaft or a low speed shaft), a gearbox 136,
a high speed shaft 138, and a coupling 140. Rotation of rotor shaft 134 rotatably
drives gearbox 136 that subsequently drives high speed shaft 138. High speed shaft
138 rotatably drives generator 132 via coupling 140 and rotation of high speed shaft
138 facilitates production of electrical power by generator 132. Gearbox 136 is
supported by a support 142 and generator 132 is supported by a support 144. In the
exemplary embodiment, gearbox 136 uses a dual path geometry to drive high speed
shaft 138. Alternatively, rotor shaft 134 may be coupled directly to generator 132 via
coupling 140.
Nacelle 106 also includes a yaw drive mechanism 146 that rotates
nacelle 106 and rotor 108 about yaw axis 116 to control the perspective of rotor
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blades 112 with respect to the direction of wind 114. Nacelle 106 also includes at
least one meteorological mast 148 that in one embodiment, includes a wind vane and
anemometer (neither shown in Fig. 2). In one embodiment, meteorological mast 148
provides information, including wind direction and/or wind speed, to a turbine control
system 150. Turbine control system 150 includes one or more controllers or other
processors configured to execute control algorithms. As used herein, the term
"processor" includes any programmable system including systems and
microcontrollers, reduced instruction set circuits (RISC), application specific
integrated circuits (ASIC), programmable logic circuits (PLC), and any other circuit
capable of executing the functions described herein. The above examples are
exemplary only, and thus are not intended to limit in any way the definition and/or
meaning of the term processor. Moreover, turbine control system 150 may execute a
SCADA (Supervisory, Control and Data Acquisition) program.
Pitch assembly 130 is operatively coupled to turbine control system
150. In the exemplary embodiment, nacelle 106 also includes forward support
bearing 152 and aft support bearing 154. Forward support bearing 152 and aft
support bearing 154 facilitate radial support and alignment of rotor shaft 134.
Forward support bearing 152 is coupled to rotor shaft 134 near hub 110. Aft support
bearing 154 is positioned on rotor shaft 134 near gearbox 136 and/or generator 132.
Nacelle 106 may include any number of support bearings that enable wind turbine
100 to function as disclosed herein. Rotor shaft 134, generator 132, gearbox 136,
high speed shaft 138, coupling 140, and any associated fastening, support, and/or
securing device including, but not limited to, support 142, support 144, forward
support bearing 152, and aft support bearing 154, are sometimes referred to as a drive
train 156.
Fig. 3 is a perspective view of an exemplary tower section 200 that
may be used in assembling at least a portion of tower 102 (shown in Fig. 1). Fig. 4 is
an enlarged perspective view of a portion of tower section 200 taken along area 4. In
the exemplary embodiment, tower section 200 is formed from a plurality of arcuate
section panels 202. Alternatively, tower section 200 can be formed from a single
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unitary panel (not shown). Tower section 200 includes a center axis 204 that extends
therethrough. Although tower section 200 is illustrated as being conical, tower
section 200 can have any shape, including, without limitation, a cylindrical or
polygonal shape, that enables tower 102 to function as described herein. Similarly,
section panels 202 can have different shapes in addition to those specifically
described herein. For example, for a polygonal tower section 200, section panels 202
may be formed with one or more planar surfaces. In the exemplary embodiment, each
section panel 202 has a first circumferential edge 206 and an opposing second
circumferential edge 208. Section panels 202 can be made of various materials, such
as carbon steel. Within a tower, such as tower 102, at least one tower section 200
may be formed with an entry passage (not shown) that enables access to an interior
cavity of tower 102 that is at least partially defined by section panels 202. Tower
section 200 and each section panel 202 extend from a first axial edge 210 to a second
axial edge 212, an axial length Li defined between first axial edge 210 and second
axial edge 212.
In the exemplary embodiment, circumferentially-adjacent panels 202
are coupled together using at least one connector 214 to form tower section 200.
Depending on the structure and/or shape of section panels 202, connectors 214 can
also vary, as described in more detail below. In the exemplary embodiment, each
connector 214 includes an outer flange 302, an opposite inner flange 304, and a spacer
306 that extends between flanges 302 and 304. Specifically, in the exemplary
embodiment, outer flange 302, inner flange 304, and spacer 306 are oriented such that
a first slot 308 and a second slot 310 are defined within connector 214. More
specifically, in the exemplary embodiment, spacer 306 ensures that flanges 302 and
304 are radially spaced a distance Di apart such that slots 308 and 310 are defined. In
one embodiment, connector 214 is fabricated fi-om the same materials, such as carbon
steel, used in fabricating section panels 202. Alternatively, connector 214 may be
fabricated from a material different than section panels 202, and/or any material that
enables tower 102 and tower section 200 to function as described herein.
8
Connector 214 can include a joint (not shown) or any suitable
connecting mechanism that enables connector 214 to couple section panels 202.
Further, cormector 214 may be fabricated as a unitary connector or fabricated with
separate connector components. In the exemplary embodiment, each connector 214 is
formed of two T-shaped portions 312 and 314. More specifically, in the exemplary
embodiment, wherein section panels 202 are arcuate, T-shaped portions 312 and 314
are also arcuate to facilitate receiving section panels 202. Alternatively, T-shaped
portions 312 and 314 may be angular or planar, or any other cross-sectional shape that
enables tower 102 and tower section 200 to function as described herein. In the
exemplary embodiment, each T-shaped portion 312 and 314 is formed with a spacer
extension 316 and a flange extension 318.
When assembled, the spacer extension 316 of first T-shaped portion
312 is against the spacer extension 316 of second T-shaped portion 314 such that slots
308 and 310 are defined between flange extension 318 of each T-shaped portion 312
and 314. T-shaped portions 312 and 314 can be coupled together before or after
section panels 202 have been inserted into slot 308 and/or 310, as described in more
detail below. Any suitable fastening mechanism or technique may be used to couple
spacer extensions 316 to one another. Cormector 214 can also be formed from
different configurations. For example, in one embodiment, only one T-shaped portion
includes a spacer extension and the other T-shaped portion includes only a flange
extension. Moreover, in an alternative embodiment, cormector 214 does not include
spacer 306, but rather includes an outer plate and an inner plate (neither shown). In
such an embodiment, adjacent section panels 202 contact one another or are separated
by a gap, and are positioned between the outer plate and the inner plate prior to
panels 202, the outer plate, and the irmer plate being coupled together using any
suitable coupling means, such as, bolts, welds, or rivets. In a fiirther alternative
embodiment, section panels 202 can be coupled together using only the outer plate or
the irmer plate.
In the exemplary embodiment, each connector 214 includes a plurality
of apertures 330 defined therein that extend therethrough. Although apertures 330 are
9
illustrated as being oriented in circumferential rows, it should be noted that any
number of apertures 330 and/or any orientation of apertures 330 that enables
connector 214 to couple adjacent section panels 202 together while maintaining the
strength and structural integrity of tower section 200 can be used. More specifically,
in the exemplary embodiment, apertures 330 are defined in a pair of circumferential
rows 332 that each extend fi-om a first end 334 of each connector 214 to a second end
336 of each connector. Moreover, in the exemplary embodiment, connector T-shaped
portion 314 is radially inward of T-shaped portion 312, and apertures 330 defined in
T-shaped portion 314 are substantially concentrically aligned with apertures 330
defined in T-shaped portion 312. Moreover, apertures 330 are sized and oriented to
receive bolts and/or another suitable fastener therethrough that enables section panels
202 to be securely coupled to connectors 214, as described in more detail below. In
alternative embodiments, connectors 214 may not include apertures 330, but rather
welds and/or rivets are used to couple section panels 202 to connectors 214 (not
shown). In the exemplary embodiment, apertixres 330 defined in each row 332 in
cormector 214 are formed with same diameter D2 and shape. Alternatively, apertures
330 in one row 332 may have a different diameter D2 and/or shape than apertures 330
in an adjacent row 332.
Each connector 214 is sized and oriented to couple adjacent section
panels 202 together to form tower section 200. In one embodiment, section panels
202 are securely coupled to connector 214. Alternatively, section panels 202 may be
removably coupled to connector 214. In the exemplary embodiment, section panels
202 each include a plurality of apertures 342 defined therein. Panel apertures 342 are
sized and oriented to align with connector apertures 330. Specifically, in the
exemplary embodiment, apertures 342 are oriented in a pair of substantially parallel
rows that each extend substantially parallel to circumferential edges 206 and 208.
During assembly of tower section 200, first circumferential edge 206 of first section
panel 202 is inserted into cormector first slot 308, and second circumferential edge
208 of second section panel 202 is inserted into connector second slot 310. After each
circumferential edge 206 and 208 is inserted into a respective connector slot 308 and
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310, panel apertures 342 are aligned substantially concentrically with respect to
apertures 330 defined in connector 214. Accordingly, a suitable fastener, such as a
bolt, can be inserted through apertures 330 and 342 such that the fasteners extend
through flange extensions 318 and through panel circumferential edges 206 and 208
to enable section panels 202 to be securely coupled together. In the exemplary
embodiment, the fasteners extend in a substantially radial direction with respect to
section center axis 204.
In the exemplary embodiment, each cormector 214 has an axial length
L2 measured between ends 334 and 336 that is approximately the same as an axial
length Li of each section panel 202. As such, in the exemplary embodiment, each
connector 214 extends along entire axial length Li of panel circumferential edges 206
and 208. Alternatively, cormector 214 only covers a portion of axial length Li of
panel circumferential edges 206 and 208. In such an alternative embodiment, a
plurality of connectors 214 may be coupled end-to-end along the full axial length Li
of panel circumferential edges 206 and 208. Alternatively, in such an embodiment,
connectors 214 may be spaced along axial length Li.
Fig. 5 is a perspective cross-sectional view of a portion of alternative
tower sections 400 that may be used in assembling at least a portion of tower 102
(shown in Fig. 1). In the exemplary embodiment, tower sections 400 include a lower
tower section 402 that is a conical tower section that is formed from section panels
202 as described herein with respect to tower section 200 (shown in Fig. 3), and an
upper tower section 404 that is a unitary section. Alternatively, lower tower section
402 could be coupled to another tower section 404 that is formed of section panels
202 as opposed to a unitary tower section (not shown). In one embodiment, to
facilitate improving the stability and stiffness of tower 102, when two tower sections
200 that are each formed of section panels 202 are coupled together, the tower
sections 200 are oriented such that the connectors 214 on the tower sections 200 are
not vertically aligned with each other.
11
In the exemplary embodiment, upper tower section 404 includes a
lower flange 408 that is annular and substantially planar, and lower tower section 402
includes an upper flange 406 that is annular and substantially planar. Moreover, in
the exemplary embodiment, each flange 406 and 408 is substantially circular. Flanges
406 and 408 each include a plurality of apertures 410 defined therein that are sized
and oriented to receive a plurality of fasteners (not shown) therethrough to enable
upper flange 406 to securely couple to lower flange 408. In alternative embodiments,
welds or rivets can also be used to securely couple flanges 406 and 408 together.
Flanges 406 and/or 408 may be formed unitarily with section panels 202 and/or may
be coupled to tower sections 402 and 404. Moreover, although flanges 406 and 408
are illustrated as extending radially inward from tower sections 402 and 404, in other
embodiments, at least a portion of flanges 406 and/or 408 could extend radially
outward from tower sections 402 and 404.
Fig. 6 is a perspective cross-sectional view of an alternative connection
between a lower tower section 402 and an upper tower section 404. In the exemplary
embodiment, a horizontal connector 420 is used to couple lower tower section 402 to
upper tower section 404. In the exemplary embodiment, horizontal connector 420 has
a structure similar to connector 214. More specifically, horizontal cormector 420
includes an outer flange 422, an opposite inner flange 424, and a spacer 426 that
extends between flanges 422 and 424. Specifically, in the exemplary embodiment,
outer flange 422, inner flange 424, and spacer 426 are oriented such that a lower slot
428 and an upper slot 430 are defined within connector 420.
Horizontal connector 420 can include a joint (not shown) or any
suitable cormecting mechanism that enables connector 420 to couple lower tower
section 402 to upper tower section 404. In the exemplary embodiment, connector 420
is a unitary connector. In alternative embodiments, connector 420 may be fabricated
from separate connector components which may be coupled to one another, adjacent
to one another, and/or spaced apart from one another. In the exemplary embodiment,
horizontal connector 420 includes a plurality of apertures 440 defined therein that
extend therethrough, similar to apertures 330 in connector 214. Moreover, apertures
12
440 are sized and oriented to receive bolts and/or another suitable fastener
therethrough that enables lower tower section 402 and upper tower section 404 to be
securely coupled to horizontal connector 420. In alternative embodiments, horizontal
connector 420 may not include apertures 440, but rather welds and/or rivets are used
to couple lower tower section 402 and upper tower section 404 to horizontal
connector 420 (not shown). In the exemplary embodiment, lower tower section 402
and upper tower section 404 each include a plurality of apertures 450 defined therein.
Apertures 450 are sized and oriented to align with horizontal connector apertures 440.
To couple lower tower section 402 to upper tower section 404, an
upper edge 460 of lower tower section 402 is inserted into horizontal coimector lower
slot 428, and a lower edge 462 of upper tower section 404 is inserted into horizontal
connector upper slot 430. After upper edge 460 and lower edge 462 are inserted into
lower slot 428 and upper slot 430, respectively, apertures 450 are aligned substantially
concentrically with respect to apertures 440 defined in horizontal connector 420.
Accordingly, a suitable fastener, such as a bolt, can be inserted through apertures 440
and 450 such that the fasteners extend through horizontal coimector 420 and through
upper edge 460 and lower edge 462 to enable lower tower section 402 and upper
tower section 404 to be securely coupled together.
Fig. 7 is a perspective view of an exemplary section panel 500 that
may be used in assembling at least a portion of tower 102. In the exemplary
embodiment, section panel 500 includes an alternative section coimector 502. Section
connector 502 may be formed unitarily with section panel 500 and/or coupled to
section panel 500 using any other suitable means. In the exemplary embodiment,
section connector 502 is substantially arcuate and includes a first flange portion 504
and a second flange portion 506. First flange portion 504 is sized and oriented to
couple to a second flange portion 506 extending from an adjacent section panel 500.
In the exemplary embodiment, first flange portion 504 includes pegs 508 and second
flange portion 506 includes corresponding apertures 510 that are sized and oriented to
enable first flange portion 504 to couple to a second flange portion 506 extending
from an adjacent section panel 500. More specifically, in the exemplary embodiment,
13
flange portions 504 and 506 are substantially planar, and a second flange portion 506
extends from a first section panel 500 and overlaps a first flange portion 504
extending from a second section panel 500 when pegs 508 are inserted into apertures
510 to couple flange portions 504 and 506 together. Alternatively, first flange portion
504 and second flange portion 506 may be coupled together using any other fasteners
and/or any suitable coupling means, including, but not limited to, welds or rivets.
When section panels 500 are coupled together using section connectors
502 to form a tower section, section connectors 502 form an annular and substantially
planar flange (not shown) that is similar to upper circular flange 406 and lower
circular flange 408 (both shown in Fig. 5). In the exemplary embodiment, section
connectors 502 are suitably flexible such that in the formed flange, one section
connector 502 can flex to reduce hoop stress on the formed flange. Moreover, section
connectors 502 are generally less expensive and are generally easier to manufacture
then a unitary flange. Furthermore, advantageously, such connectors 502 may also be
fabricated imitarily with a section panel 500.
Fig. 8 is a perspective view of a polygonal tower section 600 that may
be used in assembling at least a portion of tower 102 (shown in Fig. 1). Fig. 9 is a
plan view of tower section 600. In the exemplary embodiment, tower section 600 is
formed from a plurality of section panels 602. In one embodiment, tower section 600
is formed from four section panels 602 that are oriented such that each section panel
602 forms a quarter of tower section 600. Alternatively, tower section 600 can be
formed from any number of section panels 602 that enables tower section 600 to
function as described herein.
Fig. 10 is an enlarged view of a portion of a section panel 602 coupled
to an alternative tower section 606. In the exemplary embodiment, section panel 602
is coupled to an upper flange portion 608, and tower section 606 is coupled to a lower
flange 610. In the exemplary embodiment, tower section 606 is substantially
cylindrical, and lower flange 610 is annular, substantially planar, and coupled to
upper flange portion 608 using fasteners 612. Alternatively, lower flange 610 and
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upper flange portion 608 may be coupled together using any other suitable coupling
means, including, but not limited to, bolts, welds, or rivets.
As compared to known imitary tower sections, the modular tower
sections described herein enable construction of larger tower sections because the
section panels can be transported unassembled and independently. Moreover, section
panels are generally more inexpensive and simpler to manufacture than unitary tower
sections. Further, the connectors described herein improve facilitating the alignment
of section panels during assembly because the spacer elements and slots secure the
position of the section panels during assembly. Moreover, as compared to unitary
flanges, the section connectors described herein facilitate reducing hoop stresses
induced to the tower sections because the section connectors are flexible with respect
to one another.
The above described modular tower sections and methods provide an
improved modular tower. The tower sections include section panels and connectors,
which can be transported unassembled and independently, such that larger tower
sections than those practically transportable can be assembled on site. As a result,
modular towers with higher hub heights can be constructed. Further, the tower
sections include a connector including an outer flange, an inner flange, and a spacer to
define a first and second slot. The defined slots facilitate positioning and coupling
section panels to form the tower section. Moreover, the tower sections include
flexible section cormectors that couple to one another to form a flange. As a result,
the formed flange is better at reducing hoop stress than a unitary flange.
Exemplary embodiments of a modular tower, modular tower sections,
and methods for constructing a modular tower are described above in detail. The
methods and systems described herein 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 methods and systems described herein may have
other applications not limited to practice with wind turbines, as described herein.
15
Rather, the methods and systems described herein can be implemented and utilized in
connection with various other industries.
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.
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 language
of the claims.

We Claim:
1. A tower assembly (200) for use with a modular tower (102), said tower
assembly comprising:
a plurality of assembly panels (202) each comprising a pair of opposing
circumferential edges (206,208); and,
a plurality of connectors (214) for use in coupling adjacent assembly panels of
said plurality of assembly panels to one another, each connector of said plurality of
connectors comprising an outer flange (302), an inner flange (304), and a spacer (306)
extending therebetween, said outer flange is spaced a distance from said inner flange
such that a first slot (308) and a second slot (310) are defined between said outer and
inner flanges, each of said first and said second slots is sized to receive one of said
assembly panel circumferential edges therein to enable said adjacent assembly panels
to be coupled to one another.
2. A tower assembly (200) in accordance with claim 1, wherein said spacer
(306) comprises a first portion (316) extending from said outer flange (302) and a
second portion (316) extending from said inner flange (304).
3. A tower assembly (200) in accordance with claim 1, wherein each of said
plurality of assembly panels (202) comprises a plurality of apertures (342) extending
therethrough, each of said plurality of assembly panel apertures facilitates securely
coupling said adjacent assembly panels to one another.
4. A tower assembly (200) in accordance with claim 3, wherein each of said
connector flanges (302, 304) comprises a plurality of apertures (330) defined therein,
said plurality of assembly panel apertures (342) and said plurality of connector
apertures are oriented to be substantially concentrically aligned when said adjacent
assembly panels (202) are coupled to said connector (214).
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5. A tower assembly (200) in accordance with claim 1, wherein each of said
plurality of assembly panels (202) has a shape defined at each of said circumferential
edges (206, 208), said connector first and second slots (308, 310) have a shape
defined between said outer and inner flanges (302, 304) that substantially mirrors the
shape of each of said plurality of assembly panels.
6. A tower assembly (200) in accordance with claim 1, wherein at least one of
said plurality of assembly panels (202) comprises one of an arcuate cross-sectional
shape and a substantially planar cross-sectional shape.
7. Amodulartower (102), comprising:
at least one lower tower section (402) comprising:
a plurality of section panels (202) each comprising a pair of opposing
circumferential edges (206, 208); and,
a plurality of connectors (214) for use in coupling adjacent section
panels of said plurality of section panels to one another, each of said
connectors comprising an outer flange (302), an irmer flange (304), and a
spacer (306) extending therebetween, said outer flange is spaced a distance
fi-om said inner flange such that a first slot (308) and a second slot (310) are
defined between said outer and inner flanges, each of said first and said second
slots is sized to receive one of said section panel circumferential edges therein
to enable said adjacent section panels to be coupled together; and,
at least one upper tower section (404) coupled to said lower section.
8. A modular tower (102) in accordance with claim 7, wherein said upper
tower section (404) comprises a unitary upper tower section.
9. A modular tower (102) in accordance with claim 7, wherein said lower
tower section (402) comprises a first annular flange (406), said upper tower section
18
(404) comprises a second annular flange (408), said first and said second annular
flanges facilitate coupling said upper tower section to said lower tower section.
10. A modular tower (102) in accordance with claim 9, wherein said first
annular flange (406) is formed from a plurality of arcuate cormectors (502), each of
said plurality of arcuate cormectors comprises:
a first flange portion (504); and,
a second flange portion (506) sized and oriented to couple to a first
flange portion extending from an adjacent one of said plurality of arcuate cormectors.