U.S. patent application number 13/180942 was filed with the patent office on 2013-01-17 for visual inspection of turbine blades.
This patent application is currently assigned to Clipper Windpower, Inc.. The applicant listed for this patent is Kevin R. Till. Invention is credited to Kevin R. Till.
Application Number | 20130017086 13/180942 |
Document ID | / |
Family ID | 47519007 |
Filed Date | 2013-01-17 |
United States Patent
Application |
20130017086 |
Kind Code |
A1 |
Till; Kevin R. |
January 17, 2013 |
VISUAL INSPECTION OF TURBINE BLADES
Abstract
A blade monitoring system is provided for inspecting the
condition of at least one turbine blade of a wind turbine
generator. The wind turbine blade condition monitoring system
includes a wind turbine which has at least one blade mounted on a
hub, the hub mounted to a nacelle body along an axis of rotation,
the nacelle being supported on a tower. A storage location is
connected to at least one of the nacelle body and the tower and
includes an opening. A storage door is mounted to and selectively
covers the opening, acting to enclose the storage location. The
blade monitoring system also includes imaging equipment for imaging
the at least one blade and a conveyance system. The conveyance
system is mounted to at least one of the nacelle body and the tower
and is connected to the imaging equipment. The conveyance system
conveys the imaging equipment from within the storage location
through the opening in a direction generally parallel to a
longitudinal axis of the at least one blade.
Inventors: |
Till; Kevin R.;
(Carpinteria, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Till; Kevin R. |
Carpinteria |
CA |
US |
|
|
Assignee: |
Clipper Windpower, Inc.
|
Family ID: |
47519007 |
Appl. No.: |
13/180942 |
Filed: |
July 12, 2011 |
Current U.S.
Class: |
416/61 |
Current CPC
Class: |
F05B 2270/8041 20130101;
F03D 17/00 20160501; F05B 2260/50 20130101; F05B 2260/80
20130101 |
Class at
Publication: |
416/61 |
International
Class: |
F01D 5/00 20060101
F01D005/00 |
Claims
1. A wind turbine blade condition monitoring system comprising: a
wind turbine including: at least one blade mounted on a hub, the
hub mounted to a nacelle along an axis of rotation, the nacelle
being supported on a tower; a storage location connected to or
defined in at least one of the nacelle and the tower and including
an opening; a storage door mounted to and selectively covering the
opening, acting to enclose the storage location; imaging equipment
for imaging the at least one blade; and, a conveyance system
mounted to at least one of the nacelle and the tower and connected
to the imaging equipment, the conveyance system conveying the
imaging equipment from within the storage location through the
opening and in a direction generally parallel to a longitudinal
axis of the at least one blade.
2. The wind turbine blade condition monitoring system according to
claim 1, wherein the conveyance system comprises an
electromechanical pulley system, comprising: a first pulley mounted
to the at least one of the nacelle and the tower; a first support
cable mounted on the first pulley; the first support cable
including a load end and a winding end, the winding end driven by a
motor unit that rotates the pulley; and, wherein the load end is
attached to the imaging equipment.
3. The wind turbine blade condition monitoring system according to
claim 2, wherein the conveyance system further comprises: a second
pulley mounted to the at least one of the nacelle and the tower; a
second support cable mounted on the second pulley; the second
support cable including a load end and a winding end; the load end
attached to the enclosure at a location spaced from the first
support cable point of attachment.
4. The wind turbine blade condition monitoring system according to
claim 1, wherein the conveyance system comprises an
electromechanical pulley and track system, comprising: a track
mounted to the tower; a carriage which travels along the track; a
system of pulleys mounted to the nacelle; a support cable supported
by the system of pulleys; the support cable including a load end
and a winding end, the winding end driven by a motor unit that
rotates at least one of the system of pulleys; the load end
attached to the carriage; and, wherein the enclosure is attached to
the carriage.
5. The wind turbine blade condition monitoring system according to
claim 1, wherein the conveyance system further comprises a
personnel lifting basket, including; at least one pulley mounted
inside the nacelle; a support cable supported by the at least one
pulley; the support cable including a load end and a winding end,
the winding end driven by a motor unit that rotates the at least
one pulley; the load end attached to a basket; and wherein the
imaging equipment is attached to the basket.
6. The wind turbine blade condition monitoring system according to
claim 1, further including sealing surfaces defined on at least one
of the storage door and the storage location for sealingly engaging
the storage door with the storage location.
7. The wind turbine blade condition monitoring system according to
claim 1, further comprising a data receiving system containing
processing and analyzing algorithms to analyze data transmitted by
the imaging equipment.
8. The wind turbine blade condition monitoring system according to
claim 1, wherein the imaging equipment includes a camera and a
lens.
9. The wind turbine blade condition monitoring system according to
claim 8, further comprising a housing unit defining a hollow
chamber holding the imaging equipment and a transparent viewing
window, wherein the lens of the imaging equipment faces the
transparent viewing window.
10. A wind turbine blade condition monitoring system, comprising:
imaging equipment for imaging at least one portion of a blade of an
associated wind turbine; a conveyance system mounted to at least
one of a nacelle and a tower of the associated wind turbine, the
conveyance system comprising: a first pulley mounted to the at
least one of the nacelle and the tower of the associated wind
turbine; a first motor for selectively rotating the first pulley; a
first support cable mounted to the first pulley, the first support
cable including a load end connected to the imaging equipment and a
winding end mounted on the first pulley; wherein the conveyance
system moves the imaging equipment in a direction generally
parallel to a longitudinal axis of the blade of the associated wind
turbine from adjacent a root end of the blade to a tip end
thereof.
11. The wind turbine blade condition monitoring system according to
claim 10, wherein the conveyance system further comprises: a second
pulley mounted to the at least one of the nacelle and the tower of
the associated wind turbine; a second support cable mounted to the
second pulley, the second support cable including a winding end
mounted on the second pulley and a load end connected to the
imaging equipment at a point spaced apart from the first support
cable point of connection.
12. The wind turbine blade condition monitoring system according to
claim 11, wherein the conveyance system further comprises a second
motor for selectively rotating the second pulley.
13. The wind turbine blade condition monitoring system according to
claim 10, wherein the conveyance system further comprises a data
cable carrying data transmitted by the imaging system to a
receiving system mounted to the nacelle of the associated wind
turbine.
14. The wind turbine blade condition monitoring system according to
claim 10, further comprising a radio frequency transmitter for the
remote transmission of data to one of the nacelle of the associated
wind turbine and a remote location.
15. The wind turbine blade condition monitoring system according to
claim 10, wherein the imaging equipment includes a camera and
lens.
16. The wind turbine blade condition monitoring system according to
claim 10, wherein the conveyance system further comprises a track
mounted to a tower of the associated wind turbine.
17. The wind turbine blade condition monitoring system according to
claim 10, wherein the conveyance system further comprises a
carriage running on the track, the enclosure being mounted to the
carriage.
18. The wind turbine blade condition monitoring system according to
claim 10, further comprising a housing unit defining a hollow
chamber accommodating the imaging equipment and a transparent
viewing window, wherein the lens of the imaging equipment faces the
transparent viewing window.
19. The wind turbine blade condition monitoring system according to
claim 10 wherein the enclosure is mounted to a personnel basket
which is moved by the conveyance system.
Description
BACKGROUND
[0001] The present exemplary embodiment relates to wind turbines.
More particularly, it relates to a monitoring system for inspecting
the condition of wind turbine rotor blades.
[0002] The increasingly complex and optimized blade designs of wind
turbine generators, along with the increase in physical scale and
sheer volume of off-shore wind turbines, have made the need for
blade condition monitoring more critical to ensure early warning of
potential design, manufacture, assembly or operation induced damage
to the blades.
[0003] A variety of camera systems for monitoring the condition of
wind turbine components are known. The current state of the art for
inspecting turbine blades in fully assembled wind turbine
generators includes periodic human inspection of the blades through
cameras statically mounted to the wind turbine. Also known is the
use of a camera mounted to a lifting device positioned on a vehicle
driven up to the tower on which the blades are to be inspected.
These methods are subject to a number of limitations. There are
environmental restrictions on when such inspections can occur, as
well as inaccuracies due to the subjectiveness of the inspection.
In addition, there is the physical distance from which the
inspection takes place. Inspecting wind turbines mounted in a water
environment is particularly problematic due to the relative
inaccessibility of such turbines, as well as humidity and corrosion
issues. With regard to statically mounted cameras, a limitation is
the narrow area of the blade that can be imaged by the camera.
[0004] It would be advantageous to provide for automated inspection
of wind turbine blades in a wider range of environmental conditions
with the ability to inspect the entire blade from root to tip at a
closer distance. It would also be desirable to improve the
objectiveness of the inspection through processing and analyzing
algorithms.
BRIEF DESCRIPTION
[0005] According to one embodiment of the present disclosure, a
wind turbine blade condition monitoring system is provided. In
accordance with this embodiment of the disclosure, the wind turbine
blade condition monitoring system comprises a wind turbine
including at least one blade mounted on a hub, the hub mounted to a
nacelle body along an axis of rotation, the nacelle body being
supported on a tower. A storage location is connected to or defined
in at least one of the nacelle body and the tower. The storage
location includes an opening, and a storage door mounted to and
selectively covering the opening, and acting to enclose the storage
location. The system also includes imaging equipment for imaging
the at least one blade and a conveyance system mounted to at least
one of the nacelle and the tower and connected to the imaging
equipment. The conveyance system conveys the imaging equipment from
within the storage location through the opening in a direction
generally parallel to a longitudinal axis of the at least one
blade.
[0006] In accordance with another embodiment of the present
disclosure, a wind turbine blade monitoring system is provided. The
wind turbine blade condition monitoring system comprises imaging
equipment for imaging at least one portion of a blade of an
associated wind turbine and a conveyance system mounted to at least
one of a nacelle and a tower of the associated wind turbine. The
conveyance system comprises a first pulley mounted to the at least
one of the nacelle and the tower of the associated wind turbine, a
first motor for selectively rotating the first pulley, and a first
support cable mounted to the first pulley. The first support cable
includes a load end connected to the enclosure and a winding end
mounted on the first pulley. The conveyance system moves the
imaging equipment in a direction generally parallel to a
longitudinal axis of the blade of the associated wind turbine from
adjacent a root end of the blade to a tip end thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] The disclosure may take form in various components and
arrangements of components as will be pointed out more fully
hereinafter in conjunction with the written description of the
preferred embodiments and illustrated in the accompanying drawings
in which:
[0008] FIG. 1 is a schematic view of a wind turbine and a wind
turbine blade condition monitoring system according to one
embodiment of the present disclosure;
[0009] FIG. 1A is a schematic view of an alternative embodiment of
a wind turbine blade condition monitoring system according to the
present disclosure, where the conveyance system attaches to the
enclosure at multiple attachment points;
[0010] FIG. 2A is a schematic view of another alternative
embodiment of a wind turbine blade condition monitoring system
according to the present disclosure, where the conveyance system
comprises an electromechanical pulley and track system;
[0011] FIG. 2B is a schematic view of still another alternative
embodiment of a wind turbine blade condition monitoring system
according to the present disclosure;
[0012] FIG. 2C is a schematic view of yet another alternative
embodiment of a wind turbine blade condition monitoring system
according to the present disclosure;
[0013] FIG. 3 is an enlarged exploded schematic view of an
enclosure and imaging equipment of the monitoring system of FIG.
1;
[0014] FIG. 4 is a schematic view of a further alternative
embodiment of a wind turbine blade condition monitoring system
according to the present disclosure;
[0015] FIG. 4A is an enlarged schematic top plan view of a portion
of the monitoring system of FIG. 4;
[0016] FIG. 5 is an enlarged schematic side view of a nacelle
storage door of the monitoring system of FIG. 1 sealingly engaged
to the nacelle body;
[0017] FIG. 6 is a schematic view of a wind turbine blade condition
monitoring system according to a yet further embodiment of the
present disclosure;
[0018] FIG. 7 is a schematic view of a further alternative
embodiment of a wind turbine blade condition monitoring system
according to the present disclosure; and,
[0019] FIG. 8 is a schematic view of still a further embodiment of
the present disclosure.
DETAILED DESCRIPTION
[0020] Referring now in greater detail to the drawings wherein the
showings are for purposes of illustrating several embodiments of
the disclosure only and not for limiting same. FIG. 1 depicts one
embodiment of a turbine blade monitoring system. In this
embodiment, the wind turbine blade condition monitoring system
utilizes an electromechanical pulley system for selectively moving
imaging equipment along the length of a turbine blade employed in a
wind turbine. The wind turbine is mounted on a tower 10 and
comprises at least one turbine blade 22 mounted to a hub 20, where
the hub 20 is attached to a nacelle 30 along an axis of rotation
24, and the nacelle 30 is mounted atop the tower 10. A storage area
32 is defined in the nacelle. In this embodiment, the storage area
is accessible from the bottom face of the nacelle. Of course, other
geometries are also contemplated. A storage door 64 is movably
mounted to the nacelle 30 and selectively covers a nacelle opening
62. The door 64 acts to enclose the storage area 32.
[0021] A conveyance system, mounted to the nacelle body 30, is
connected to and conveys an enclosure 40 from within the storage
location 32 through the opening 62 and in a direction generally
parallel to a longitudinal axis of the at least one blade 22. In
this embodiment, the enclosure 40 holds imaging equipment for
imaging the at least one blade 22. The conveyance system can
include an electromechanical pulley system, comprising a first
pulley 66 mounted to the nacelle body 30, and a first support cable
44 mounted on the first pulley 66. The first support cable 44
includes a load end and a winding end, where the winding end is
driven by a conventional motor unit (not visible) that rotates the
pulley and the load end is attached to the enclosure 40. A
power/data cable 42 is connected to imaging equipment held in the
enclosure, as is illustrated in FIG. 3. The data component of cable
42 communicates with an electronic cable 118 disposed in the
nacelle 30 and connected to a data receiving system 120. The data
receiving system 120 contains processing and analyzing algorithms
to analyze data transmitted by the imaging equipment.
[0022] It should be appreciated that the data receiving system 120
could be located remotely from the nacelle 30, if so desired.
Communication can be had with such a remotely located data
receiving system via RF, for example. In such an embodiment, a
conventional RF transmitter (see FIG. 7) could be located in the
housing 40 and the cable 42 would only be a power cable to provide
electricity to the imaging system and to the RF transmitter held in
the housing.
[0023] With reference to FIG. 1A, another embodiment of the
conveyance system of a wind turbine blade condition monitoring
system 2 is there shown. In this embodiment, like components are
identified by like numerals with a primed (') suffix, and new
components are identified by new numerals. The wind turbine
comprises at least one turbine blade 22' mounted to a hub 20',
where the hub 20' is attached to a nacelle 30', and the nacelle 30'
is attached to a tower 10'. A storage location 32' having an
opening 62' is located in the nacelle 30'. A storage door 64' is
mounted to and selectively covers the opening 62' and acts to
selectively enclose the storage area or location 32'. A conveyance
system, which can be mounted to the nacelle body 30', is connected
to and conveys an enclosure 40' from within the storage location
32' through the opening 62' and in a direction generally parallel
to a longitudinal axis of the at least one blade 22'. The enclosure
40' holds imaging equipment for imaging the at least one blade
22''.
[0024] In this embodiment, the conveyance system comprises first
and second pulleys 84, 80 mounted to the nacelle body 30'. A first
support cable 88 is mounted on the first pulley 84, and a second
support cable 82 is mounted on the second pulley 80, Each of the
support cables 82, 88 includes a load end and a winding end. The
load end of the second support cable 82 is attached to the
enclosure 40' at a location spaced from where the first support
cable 88 is attached to the enclosure 40*. Employing two or more
spaced cables is advantageous in order to reduce the tendency of
the housing 40' to swing or pivot, for example due to wind, as the
housing is moved up and down generally along a longitudinal axis of
the blade 22'. The inspection of the rotor blade is facilitated
when the blade to be inspected is placed in the 6 o'clock position,
i.e., the rotor blade is extending generally straight down from the
hub and is therefore aligned with the tower.
[0025] With reference now to FIG. 2A, another embodiment of the
conveyance system of a wind turbine blade condition monitoring
system is there shown. The wind turbine comprises at least one
turbine blade 122 mounted to a hub 120, where the hub 120 is
attached to a nacelle 130 along an axis of rotation 124, and the
nacelle 130 is attached to a tower 110. A storage area or location
132 and an opening 162 is located in a body of the nacelle 130. A
storage door 164, mounted to and selectively covering the opening
162, acts to enclose the storage location 132. A conveyance system,
mounted to the nacelle body 130, is connected to and conveys an
enclosure 140 from within the storage location 132 through the
opening 162 and in a direction generally parallel to a longitudinal
axis of the at least one blade 122. The enclosure 140 holds imaging
equipment for imaging the at least one blade 122.
[0026] In this embodiment, the conveyance system comprises an
electromechanical pulley and track system including at least one
pulley 194 and at least one roller 195 mounted to the nacelle body
130, and a support cable 196 supported by the pulleys and rollers.
A data and power cable 198 is also provided. The support cable 196
includes a load end and a winding end, where the winding end is
driven by a motor unit (not visible) that rotates the at least one
pulley 194. The load end is attached to a carriage 192. The
enclosure 140' is attached to the carriage 192 which travels along
a track 190 that is attached to the tower. The carriage 192 is
supported on the track 190 and is raised and lowered by the support
cable 196. The track 190 in this embodiment is supported by and
hangs from the nacelle 130. The track 190 also rides against the
tower 110. To this end, a series of spaced rollers 184 are attached
to the track 190. When the nacelle 130 rotates (i.e., yaws)
relative to the tower 110, the rollers allow the track to ride
against the tower and rotate with the nacelle. It should be
appreciated that the track 190 can extend down the tower 110 the
length of the blade 122 in order to enable the carriage 192 to
transport the housing 140 from a location adjacent a root end of
the blade to a location adjacent a tip end thereof. In order to
allow the housing 140 to be retracted into the nacelle 130 for
storage, an upper end of the track 190 can extend into the storage
area 132. Of course, other embodiments are also contemplated. It
should be appreciated that the storage door 164 will need to be
modified in order to accommodate the track 190.
[0027] With reference now to FIG. 2B, another embodiment of the
present disclosure is there illustrated. In this embodiment, like
components are identified by like numerals with a primed suffix (')
and new components are identified by new numerals. In this
embodiment, a track 200 is hard mounted to a tower 110' and does
not rotate with a nacelle 202. Rather, the track, relevant pulleys
194' and related components are all mounted to the tower 110' and
do not rotate with the nacelle 202. However, the nacelle still
helps form an enclosure around the carriage when it is not in use.
In this embodiment, the nacelle 202 extends well below a slew
bearing 204 which connects the tower to the nacelle to form an area
where the nacelle can still wrap around and protect equipment which
is mounted to the tower beneath the slew bearing. A portion 206 of
the nacelle 204 is hard mounted to the tower 110'. That nacelle
portion 206 is joined to the remainder of the nacelle 202 at a
circular intersection and forms a rotary joint 208, which can be
designed with baffles or serpentine seals in order to keep weather
out of the nacelle. In one embodiment, the nacelle 202 and the
nacelle portion 206 can be made of a fiberglass material. In this
embodiment, a fixed barrier 209 is provided which is mounted below
the carriage 140' to protect the carriage in the nacelle 202 until
the carriage leaves the enclosed space so as to undertake an
inspection. Such inspection will require that the blade 122' be in
a specific angular orientation in relation to the carriage
140'.
[0028] In the embodiments thus far illustrated herein, the imaging
equipment and its housing have been stored within a cavity defined
in the nacelle. However, it should be appreciated that a separate
housing member, configured for storing the imaging equipment, could
be affixed to a wall of the nacelle instead. In other words, it may
be desirable in some circumstances to provide a separate housing
member which is mounted to either the nacelle or the tower, which
housing or enclosure is meant to accommodate the imaging equipment
when such equipment is not needed for inspection of a turbine blade
of the wind turbine. One such embodiment is shown in FIG. 2C.
[0029] With reference now to FIG. 2C, another embodiment of an
inspection system is there illustrated. In this embodiment, like
components are identified by like numerals with a double primed
suffix ('') and new components are identified by new numerals. In
this embodiment, a carriage 211 is not pulled up and let down by a
cable. Rather, the carriage 211 is self propelled. In one
embodiment, the carriage 211 could be provided with gears so that
the carriage runs on a geared track 190'' in order to prevent
slippage or skidding due to gravity. In other words, a rack and
pinion type arrangement vertically oriented could be employed. Of
course, other known alternatives could be utilized as well. Imaging
equipment in the carriage can receive power from a power and data
cable 213. The carriage has an electric motor (not illustrated) or
other means so that the carriage can climb and lower itself on the
track 190''. In this embodiment, the track is hard mounted to a
tower 110''. However, the track does not extend up to a nacelle
130''. Rather, the carriage has a separate enclosure 215 mounted to
the tower for storing the carriage when it is not in use. A
suitable door 217 can be employed to close an opening in the
enclosure 215 when the carriage is put away for storage. It should
be appreciated that the door 217 is formed to accommodate the
protrusion of the track upper end into the enclosure 215.
[0030] With reference now to FIG. 3, the enclosure 40 which can
hold the imaging equipment 52, 54 is there shown. The enclosure
comprises a housing unit including a camera mount 48 defining a
hollow chamber 46. Attached thereto is a transparent viewing window
50. The imaging equipment can comprise a camera 52 which includes a
lens 54. In one embodiment, the imaging equipment can employ
visible light to image the blade. Other types of imaging equipment
are also contemplated. For example, X-ray imaging technologies or
other known means of inspection could be used to inspect the
blades. The lens 54 of the imaging equipment faces the transparent
viewing window 50 for imaging the at least one turbine blade.
[0031] With reference now to FIG. 5, one embodiment of a nacelle
door 104 is shown along with sealing surfaces with a nacelle body
100 in order to prevent exposure of the imaging equipment and its
enclosure to the elements. More particularly, sealing surfaces 106
are defined on at least one of the storage door 104 and the nacelle
body 100 for sealingly engaging the storage door with the nacelle
body. Due to the high humidity and saline environment found in
offshore wind turbine installations, the vast majority of which are
in salt water, it is very desirable to provide adequate sealing for
the nacelle so that the equipment held or stored therein is not
subjected to the environment. It is also advantageous to store the
imaging equipment in the nacelle when not needed, to keep it away
from such a marine environment. Even where the movable imaging
equipment disclosed herein is used on a wind turbine mounted on
shore, it is advantageous to store the imaging equipment in an
enclosed storage area, such as within the nacelle, when not needed
in order to retard dirt and dust from clogging the equipment.
[0032] With reference now to FIG. 4, another embodiment of a wind
turbine blade condition monitoring system 4 is there shown. In this
embodiment, the wind turbine comprises at least one turbine blade
222 mounted to a hub 220, where the hub is attached to a nacelle
230, and the nacelle is attached to a tower 210. A storage area or
location 232 and an opening 262 is located in the nacelle body 230.
In this embodiment, a rearwardly pivoting storage door 220 is
mounted to the nacelle and selectively covers the nacelle opening
262 in order to enclose the nacelle storage location 232. A
conveyance system, mounted to the nacelle body 230 is connected to
and conveys an enclosure from a storage position through the
nacelle opening 262 to an imaging position. As in the previous
embodiments, the enclosure holds imaging equipment for imaging the
at least one blade 222. The conveyance system comprises an
electromechanical pulley system, including a first pulley 226
mounted to the nacelle body 230, and a first support cable 228
mounted on the first pulley. The first support cable 228 rides on a
set of rollers or second pulleys 229. The cable includes a load end
and a winding end, where the winding end mounted on the pulley 226.
As shown in FIG. 4A, the pulley 226 is driven by a motor unit 232
that rotates the pulley and the load end is attached to the
enclosure.
[0033] With reference now to FIG. 6, illustrated therein is a
different position for the storage location according to the
present disclosure. In this embodiment, a storage location 350 is
provided outside a nacelle 352. For example, the storage location
350 can be a separate enclosure which is mounted to the nacelle
350. Alternatively, the storage location could be mounted to a
tower 354 (see FIG. 2C). The storage location includes a storage
area 356 which accommodates a conveyance system 360, as well as an
enclosure 362 which can hold holding imaging equipment for imaging
the at least one blade. While the imaging equipment is generally
shown as being held in a housing, it should be appreciated that
such a housing is not necessary under all circumstances. In other
words, the imaging equipment could itself be held in a storage
location without the need for a housing to enclose the imaging
equipment.
[0034] With reference now to FIG. 7, disclosed is a further
embodiment in which the imaging system is mounted to a personnel
lifting basket 470. In this embodiment, the wind turbine comprises
at least one turbine blade 422 mounted to a hub 420 which rotates
around an axis 424. The hub is attached to a nacelle 430, and the
nacelle is mounted on a tower 410. An access area or location 474
and an opening 478 is located in the nacelle body 430. An access
door 472 is mounted to and selectively covers the opening 478 and
acts to selectively enclose the access area or location 474. A
conveyance system, mounted to the nacelle body 430 is connected to
and conveys a personnel lifting basket 470 to and from a position
near the access area or location 474 in a direction generally
parallel to a longitudinal axis of the at least one blade 422. It
is appreciated that personnel are transported in the basket from a
base of the tower 410 to the nacelle 430. Access to the nacelle can
be provided by the illustrated ladders. In this embodiment, when
the basket 470 is not in use, it is drawn up against a bottom
surface of the nacelle 430. To this end, the door 472 is closed
before the basket is fully drawn up against the nacelle so that
somewhat of a sealing relationship can be formed between the top
edge of the basket 470 and the outer surface of the door 472. It
should be appreciated that the door 472 is formed in such a way as
to accommodate support cables 486 for the basket.
[0035] The enclosure 440 is affixed to the personnel lifting basket
470 and holds imaging equipment for imaging the at least one blade
422. As the basket 470 is raised and lowered, the at least one
blade 422 can be imaged. The conveyance system can include an
electromechanical pulley system, comprising first and second
pulleys 482 mounted to the nacelle body 430, and first and second
support cables 486 mounted on the first pulley and second pulley
respectively. The first and second support cables 486 each include
a load end and a winding end, where the winding end is spooled on a
respective pulley which is driven by a conventional motor unit (not
visible) that rotates the pulley. The load end of each cable is
attached to the personnel lifting basket 470. Of course, more than
two cables can be employed, if so desired. Three or four cables may
be preferable.
[0036] In an alternative embodiment, the information transmitted by
the imaging system is sent to a radio frequency transmitter 490
which can also be mounted in or to the basket 470. The transmitter
490 can transmit the information from the sensing system to a
remote location. Similarly, there could be a transmitter within the
nacelle 430 to transmit the information gathered by the imaging
system to a remote location. This may prove particularly
advantageous in an off shore wind farm setting.
[0037] With reference now to FIG. 8, disclosed is a further
embodiment in which the imaging system is mounted to a personnel
lifting basket 570. In this embodiment, the wind turbine comprises
at least one turbine blade 522 mounted to a hub 520 that rotates
around an axis 524. The hub is attached to a nacelle 530, and the
nacelle is mounted on a tower 510. A storage area or location 532
and an opening 562 is located in the nacelle body 530. A storage
door 564 is mounted to and selectively covers the opening 562 and
acts to selectively enclose the storage area or location 532. In
this embodiment, the nacelle 530 is enlarged in order to house the
basket 570.
[0038] A conveyance system, mounted to the nacelle body 530 is
connected to and conveys a personnel lifting basket 570 from within
the storage location 532 through the opening 562 and in a direction
generally parallel to a longitudinal axis of the at least one blade
522. The enclosure 540 is affixed to the personnel lifting basket
570 and holds imaging equipment for imaging the at least one blade
522. The conveyance system can include an electromechanical pulley
system, comprising first and second pulleys 582 mounted to the
nacelle body 530, and first and second support cables 586 mounted
on the first pulley and second pulley respectively. The first and
second support cables 586 each include a load end and a winding
end, where each winding end is spooled on a respective pulley 582
which is driven by a conventional motor unit (not visible) that
rotates the pulley. The load end of each cable is attached to the
personnel lifting basket 570.
[0039] While the imaging system is illustrated in FIGS. 7 and 8 as
being located at the base of the personnel basket 470, 570, it
should be appreciated that the imaging system could be mounted to
the personnel basket at a variety of locations. What is desirable
is that the imaging system have a clear and unobstructed view of
the at least one blade of the wind turbine.
[0040] The exemplary embodiments have been described herein.
Obviously, modifications and alterations will occur to others upon
reading and understanding the preceding detailed description. It is
intended that the exemplary embodiments be construed as including
all such modifications and alterations insofar as they come within
the scope of the appended claims or the equivalents thereof.
* * * * *