U.S. patent application number 12/743132 was filed with the patent office on 2010-12-23 for power generator.
Invention is credited to Michael John Urch.
Application Number | 20100320771 12/743132 |
Document ID | / |
Family ID | 40638259 |
Filed Date | 2010-12-23 |
United States Patent
Application |
20100320771 |
Kind Code |
A1 |
Urch; Michael John |
December 23, 2010 |
Power Generator
Abstract
An electrical power generator assembly (10a) for using kinetic
energy from a flowing fluid (12) to generate electrical power. The
electrical power generator (10a) includes a blade assembly (14) and
at least one primary coil (52). The blade assembly (14) having a
head end (16) for facing incoming flowing fluid (12), a tail end
(18) spaced from the head end (16) for facing in the direction of
the flowing fluid (12), and a rotational axis (20) extending
between the head end (16) and the tail end (18). The blade assembly
(14) includes a blade arrangement (44) which is arranged in
generally helical fashion about the rotational axis (20), and at
least one mounting formation (26, 36) connected to the blade
arrangement (44). Each mounting formation (26, 36) is adapted to
permit mounting of the blade assembly (14) for rotation about its
rotational axis (20), so that in use fluid flowing past the
electrical power generator assembly (10a) interacts with the blade
arrangement (44) to rotate the blade assembly (14) about its
rotational axis (20). The at least one primary coil (52) is
connected to the blade arrangement (44) for rotation with the blade
arrangement (44). The at least one primary coil (52) is energizable
and being arranged in use to interact with at least one stationary
secondary coil (54b) to generate electrical power in response to
rotation of the blade assembly (14).
Inventors: |
Urch; Michael John;
(Prestons, AU) |
Correspondence
Address: |
DORITY & MANNING, P.A.
POST OFFICE BOX 1449
GREENVILLE
SC
29602-1449
US
|
Family ID: |
40638259 |
Appl. No.: |
12/743132 |
Filed: |
November 14, 2008 |
PCT Filed: |
November 14, 2008 |
PCT NO: |
PCT/AU08/01704 |
371 Date: |
August 27, 2010 |
Current U.S.
Class: |
290/55 |
Current CPC
Class: |
F05B 2210/16 20130101;
F03B 17/061 20130101; F05B 2240/14 20130101; F05B 2240/133
20130101; F03D 1/0625 20130101; F03D 13/10 20160501; F03D 1/04
20130101; F03D 9/25 20160501; Y02E 10/72 20130101; Y02E 10/20
20130101; Y02E 10/30 20130101; F05B 2220/7066 20130101; F03B 11/02
20130101; F03B 13/10 20130101; F03D 1/0633 20130101; F05B 2250/25
20130101; F05B 2240/202 20130101 |
Class at
Publication: |
290/55 |
International
Class: |
F03D 9/00 20060101
F03D009/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 16, 2007 |
AU |
2007906277 |
Nov 16, 2007 |
AU |
2007906280 |
Aug 6, 2008 |
AU |
2008904025 |
Claims
1. An electrical power generator assembly for using kinetic energy
from a flowing fluid to generate electrical power, the electrical
power generator including: a blade assembly having a head end for
facing incoming flowing fluid, a tail end spaced from the head end
for facing in the direction of the flowing fluid, and a rotational
axis extending between the head end and the tail end, the blade
assembly including a blade arrangement which is arranged in
generally helical fashion about the rotational axis, and at least
one mounting formation connected to the blade arrangement, each
mounting formation being adapted to permit mounting of the blade
assembly for rotation about its rotational axis, so that in use
fluid flowing past the electrical power generator assembly
interacts with the blade arrangement to rotate the blade assembly
about its rotational axis; and at least one primary coil connected
to the blade arrangement for rotation with the blade arrangement,
said at least one primary coil being energizable and being arranged
in use to interact with at least one stationary secondary coil to
generate electrical power in response to rotation of the blade
assembly.
2. The power generator assembly as claimed in claim 1, wherein the
electrical power generator includes a plurality of primary coils,
each primary coil being connected to one of the blades at or
adjacent the tip of the blade.
3. The power generator assembly as claimed in claim 1, wherein the
electrical power also includes a current supply electrically
connected to each primary coil, for energizing each primary coil in
order to induce a magnetic field around each primary coil.
4. The power generator as claimed in claim 1, wherein the
electrical power generator also includes a current supply
electrically connected to each secondary coil, for energizing each
secondary coil in order to induce a magnetic field which induces a
current in each primary coil.
5. The power generator assembly as claimed in claim 1, wherein the
electrical power generator further includes at least one stationary
secondary coil, for magnetically communicating with each primary
coil when each primary coil is energized.
6. The power generator assembly as claimed in claim 5, wherein the
electrical power generator includes a plurality of said secondary
coils.
7. An electrical power generator assembly for using kinetic energy
from a flowing fluid to generate electrical power, the electrical
power generator including: a blade assembly having a head end for
facing incoming flowing fluid, a tail end spaced from the head end
for facing in the direction of the flowing fluid, and a rotational
axis extending between the head end and the tail end, the blade
assembly including a blade arrangement which is arranged in
generally helical fashion about the rotational axis, and at least
one mounting formation connected to the blade arrangement, each
mounting formation being adapted to permit mounting of the blade
assembly for rotation about its rotational axis, so that in use
fluid flowing past the electrical power generator assembly
interacts with the blade arrangement to rotate the blade assembly
about its rotational axis; and at least one permanent magnet
connected to the blade arrangement for rotation with the blade
arrangement, said at least one permanent magnet being arranged in
use to interact with at least one stationary secondary, coil to
generate electrical power in response to rotation of the blade
assembly.
8. The power generator assembly as claimed in claim 1, wherein the
blade assembly includes an elongated shaft extending between the
head end and the tail end of the blade assembly, the shaft having a
longitudinal axis defining the rotational axis of the blade
assembly, and the blade arrangement being mounted on and radiating
from the shaft.
9. The power generator assembly as claimed in claim 8, wherein the
blade arrangement terminates shy of the ends of the shaft, with
each mounting formation being provided by an end portion of the
shaft, so that in use, the shaft, and accordingly the blade
assembly, is rotatably mounted or supported.
10. The power generator assembly as claimed in claim 8, wherein
each mounting formation includes a bearing element mounted on the
shaft and adapted to be connected to a support structure, to permit
rotation of the blade assembly relative to said support
structure.
11. The power generator assembly as claimed in claim 1, wherein the
blade arrangement includes a plurality of beams which are
longitudinally spaced in said generally helical fashion along the
shaft.
12. The power generator assembly as claimed in claim 11, wherein
each beam is mounted on the shaft such that it is adjustably
rotatable around the rotational axis of the shaft, to permit
adjustment of the pitch of the blade assembly.
13. The power generator assembly as claimed in claim 11, wherein
the blade arrangement, further includes a web or skin extending
along the lengths of and connected to each pair of adjacent beams,
such that the blade arrangement, irrespective of the pitch of each
beam, is uninterrupted across its surface.
14. The power generator assembly as claimed in claim 1, wherein the
blade arrangement includes one or more continuous helical
blades.
15. The power generator assembly as claimed in claim 1, wherein the
blade arrangement, when seen in side elevation, tapers from the
head end thereof to its tail end.
16. The power generator assembly as claimed in claim 1, wherein the
power generator assembly also includes an elongated open-ended
shroud extending between the head end and the tail end of the blade
assembly, the shroud being connected to and surrounding the blade
assembly, so that the shroud rotates with the blade assembly in
use.
17. The power generator assembly as claimed in claim 16, wherein
the shroud has a head end and a tail end.
18. The power generator assembly as claimed in claim 16, wherein
the shroud is connected to the tip of each blade of the blade
arrangement, the connection between the shroud and each blade being
a substantially fluid impervious connection.
19. The power generator assembly as claimed in claim 16, wherein
the blade arrangement includes a plurality of beams and said webs
or skins, a tip of each web or skin is also connected to the
shroud.
20. The power generator assembly as claimed in claim 19, wherein
the connections between the webs or skins and the shroud are
substantially fluid impervious connections.
21. The power generator assembly as claimed in claim 16, wherein in
use, flowing fluid interacting with the blade arrangement to rotate
the power generator assembly thus enters the shroud from its head
end and exits the shroud via its tail end.
22. The power generator assembly as claimed in claim 16, wherein
the shroud is of thin wall construction, and converges along at
least part of its length from its head end to its tail end, said
convergence corresponding to the tapering of the blade
assembly.
23. The power generator assembly as claimed in claim 16, wherein
the shroud is of multi-section or unitary moulded construction,
having a head end section via which a flowing fluid enters the
shroud, a tail end section via which flowing fluid exits the
shroud, and an elongated intermediate section extending between the
head end section and the tail end section, with the intermediate
section converging from the head end section towards the tail end
section.
24. The power generator assembly as claimed in claim 23, wherein
the head end section of the shroud converges towards the
intermediate section, and the tail end section diverges away from
the intermediate section, such that the shroud is generally in the
form of a converging-diverging venturi having a converging
elongated throat defined by the intermediate section.
25. The power generator assembly as claimed in claim 23, wherein
the shroud has a circular cross-sectional profile, so that the head
end section and the tail end section of the shroud are flared in
bell mouth fashion.
26. The power generator assembly as claimed in claim 1, wherein
each mounting formation includes a bearing element connected to an
end section of the shaft, the bearing elements in use being mounted
on an anchored support structure, such that the power generator
assembly rotates relative to the support structure.
27. The power generator assembly as claimed in claim 1, wherein the
power generator assembly includes a stator in front of the
shroud.
28. The power generator assembly as claimed in claim 1, wherein the
power generator assembly includes a slotted ejector arrangement
behind the shroud.
29. The power generator assembly as claimed in claim 28, wherein
the slotted ejector arrangement is adjacent the shroud tail end
section.
30. The power generator assembly as claimed in claim 28, wherein
the slotted ejector arrangement is connected to, and rotates with,
the shroud.
31. The power generator assembly as claimed in claim 28, wherein
the slotted ejector arrangement is not connected to, and does not
rotate with, the shroud.
32. The power generator assembly as claimed in claim 28, wherein
the slotted ejector arrangement includes a plurality of spaced
apart tubular sections.
33. The power generator assembly as claimed in claim 28, wherein
the slotted ejector arrangement is of unitary construction, with a
helical slot therein.
34. The power generator assembly as claimed in claim 32, wherein
the slotted ejector arrangement diverges diametrically away from
the shroud.
35. The power generator assembly as claimed in claim 33, wherein
the assembly includes a drive means adapted to vary the axial
length of the slotted ejector arrangement.
36. The power generator assembly as claimed in claim 33, wherein
the assembly includes a drive means adapted to vary the axial
length and radial width of the slotted ejector arrangement.
37. An electrical power generator assembly for using kinetic energy
from a flowing fluid to generate power, the electrical power
generator including: a blade assembly having a head end for facing
incoming flowing fluid, a tail end spaced from the head end for
facing in the direction of the flowing fluid, and a rotational axis
extending between the head end and the tail end, the blade assembly
including a blade arrangement which includes a plurality of blades
spaced along the length of the rotation axis, and at least one
mounting formation connected to the blade arrangement, each
mounting formation being adapted to permit mounting of the blade
assembly for rotation about its rotational axis, so that in use
fluid flowing past the electrical power generator assembly
interacts with the blade arrangement to rotate the blade assembly
about its rotational axis; and at least one primary coil connected
to the blade arrangement for rotation with the blade arrangement,
the primary coil being arranged in use to interact with at least
one stationary secondary coil to generate power in response to
rotation of the blade assembly.
38. An electrical power generator installation, the installation
including: an electrical power generator as hereinbefore described
including at least one secondary coil; and a support structure, the
electrical power generator being mounted, by means of each mounting
formation of the blade arrangement, on the support structure for
rotation of the blade arrangement about its rotational axis, and
each secondary coil of the power generator being mounted on the
mounting structure.
39. The power generator installation as claimed in claim 38,
wherein the power generator is submerged in the ocean.
40. The power generator installation as claimed in claim 38,
wherein the power generator is submerged in a river or flowing
stream.
41. The power generator installation as claimed in claim 38,
wherein the power generator is located in an open area where it
will be exposed to flow of air when the wind blows.
42. The power generator installation as claimed in claim 38,
wherein the support structure includes a network of flexible
elements.
43. The power generator assembly as claimed in claim 42, wherein
the network of flexible elements include (heavy) chains or
cables.
44. The power generator assembly as claimed in claim 42, wherein
the network of flexible elements are arranged such that the
generator can be aligned such that the inlet end of the shroud
opposes the direction of flow of the fluid.
45. The power generator assembly as claimed in claim 44, wherein
the generator aligns itself in accordance with the direction of
flow of a fluid.
46. The power generator assembly as claimed in claim 42, wherein
the network of flexible elements are arranged such that the
generator is mounted thereon in the general fashion of a
windsock.
47. The power generator assembly as claimed in claim 38, wherein
the support structure is a rigid structure including a network of
rigid elements.
48. A propulsion or pump device adapted to eject a fluid, the
propulsion or pump device including: a blade assembly having a head
end for facing incoming flowing fluid, a tail end spaced from the
head end for facing in the direction of the flowing fluid, and a
rotational axis extending between the head end and the tail end,
the blade assembly including a blade arrangement which is arranged
in generally helical fashion about the rotational axis, and at
least one mounting formation connected to the blade arrangement,
each mounting formation being adapted to permit mounting of the
blade assembly for rotation about its rotational axis, so that in
use rotation of the blade assembly about its rotational axis
interacts with fluid flowing through the electrical power generator
assembly; and at least one primary coil connected to the blade
arrangement for rotation with the blade arrangement, said at least
one primary coil being arranged in use to interact with at least
one stationary secondary coil to generate rotation of the blade
assembly in response to electrical power being applied to said at
least one stationary secondary coil.
Description
TECHNICAL FIELD
[0001] The present invention relates generally to a power
generator, and more particularly to an electrical power generator
assembly for using kinetic energy from a flowing fluid to generate
power.
[0002] The present invention relates also to an electrical power
generator installation including such electrical power generator.
The present invention is expected to be particularly
advantageously, but not exclusively, used in the context of
hydro-powered electricity generation.
BACKGROUND OF THE INVENTION
[0003] Kinetic energy in flowing fluids, such as water and wind, is
a known alternative to energy sources such as bio-fuels and fossil
fuels for generating power. Unlike, for example, bio- and fossil
fuel which, when used in electrical power generation, go
hand-in-hand with emission of harmful combustion gasses into the
atmosphere, generation of is power by using flowing fluids has no
or very little adverse effects on the atmosphere. Although known
installations for harvesting wind power generally have low running
costs, they tend to be expensive to install and have relatively low
generation capacity. Known installations for harvesting hydropower,
for example tidal power, on the other hand, have relatively higher
generation capacity. However, these types of installations too are
expensive, require frequent maintenance, and could be unreliable
due to problems associated with silting and corrosion.
OBJECT OF THE INVENTION
[0004] It is the object of the present invention to substantially
overcome or at least ameliorate one or more of the above
disadvantages, or at least to provide a useful alternative.
SUMMARY OF THE INVENTION
[0005] In one aspect, the present invention provides an electrical
power generator assembly for using kinetic energy from a flowing
fluid to generate electrical power, the electrical power generator
including:
[0006] a blade assembly having a head end for facing incoming
flowing fluid, a tail end spaced from the head end for facing in
the direction of the flowing fluid, and a rotational axis extending
between the head end and the tail end, the blade assembly including
a blade arrangement which is arranged in generally helical fashion
about the rotational axis, and at least one mounting formation
connected to the blade arrangement, each mounting formation being
adapted to permit mounting of the blade assembly for rotation about
its rotational axis, so that in use fluid flowing past the
electrical power generator assembly interacts with the blade
arrangement to rotate the blade assembly about its rotational axis;
and
[0007] at least one primary coil connected to the blade arrangement
for rotation with the blade arrangement, said at least one primary
coil being energizable and being arranged in use to interact with
at least one stationary secondary coil to generate electrical power
in response to rotation of the blade assembly.
[0008] The electrical power generator preferably includes a
plurality of primary coils, each is primary coil being connected to
one of the blades at or adjacent the tip of the blade.
[0009] In one form, the electrical power generator may also include
a current supply electrically connected to each primary coil, for
energizing each primary coil in order to induce a magnetic field
around each primary coil. In another form, the electrical power
generator may also include a current supply electrically connected
to each secondary coil, for energizing each secondary coil in order
to induce a magnetic field which induces a current in each primary
coil.
[0010] Preferably, the electrical power generator yet further
includes a said at least one stationary secondary coil, for
magnetically communicating with each primary coil when each primary
coil is energized. The electrical power generator, preferably,
includes a plurality of said secondary coils.
[0011] In a second aspect, the present invention provides an
electrical power generator assembly for using kinetic energy from a
flowing fluid to generate electrical power, the electrical power
generator including:
[0012] a blade assembly having a head end for facing incoming
flowing fluid, a tail end spaced from the head end for facing in
the direction of the flowing fluid, and a rotational axis extending
between the head end and the tail end, the blade assembly including
a blade arrangement which is arranged in generally helical fashion
about the rotational axis, and at least one mounting formation
connected to the blade arrangement, each mounting formation being
adapted to permit mounting of the blade assembly for rotation about
its rotational axis, so that in use fluid flowing past the
electrical power generator assembly interacts with the blade
arrangement to rotate the blade assembly about its rotational axis;
and
[0013] at least one permanent magnet connected to the blade
arrangement for rotation with the blade arrangement, said at least
one permanent magnet being arranged in use to interact with at
least one stationary secondary coil to generate electrical power in
response to rotation of the blade assembly.
[0014] The blade assembly preferably includes an elongated shaft
extending between the head end and the tail end of the blade
assembly, the shaft having a longitudinal axis defining the
rotational axis of the blade assembly, and the blade arrangement
being mounted on and radiating from the shaft. The generator is
preferably drivingly connected to the shaft. The blade arrangement
preferably terminates shy of the ends of the shaft, with each
mounting formation being provided by an end portion of the shaft,
so that in use, the shaft, and accordingly the blade assembly, is
rotatably mounted or supported. Preferably, each mounting formation
includes a bearing element mounted on the shaft and adapted to be
connected to a support structure, to permit rotation of the blade
assembly relative to said support structure.
[0015] In one embodiment, the blade arrangement preferably includes
a plurality of beams which are longitudinally spaced in said
generally helical fashion along the shaft. In this embodiment, each
beam is preferably mounted on the shaft such that it is adjustably
rotatable around the rotational axis of the shaft, to permit
adjustment of the pitch of the blade assembly. The blade
arrangement, in this embodiment, further preferably includes a web
or skin extending along the lengths of and connected to each pair
of adjacent beams, such that the blade arrangement, irrespective of
the pitch of each beam, is uninterrupted across its surface.
[0016] In another embodiment, if desired, the blade arrangement
preferably includes one or more continuous helical blades.
[0017] Preferably, the blade arrangement, when seen in side
elevation, tapers from the head end thereof to its tail end.
[0018] The power generator assembly preferably also includes an
elongated open-ended shroud extending between the head end and the
tail end of the blade assembly, the shroud being connected to and
surrounding the blade assembly, so that the shroud rotates with the
blade assembly in use. The shroud too thus has a head end and a
tail end. Preferably, the shroud is connected to the tip of each
blade of the blade arrangement, the connection between the shroud
and each blade being a substantially fluid impervious connection.
Likewise, in the embodiment where the blade arrangement includes a
plurality of beams and said webs or skins, a tip of each web or
skin is, preferably, also connected to the shroud. Preferably, the
connections between the webs or skins and the shroud are
substantially fluid impervious connections. In use, flowing fluid
interacting with the blade arrangement to rotate the power
generator assembly thus enters the shroud from its head end and
exits the shroud via its tail end.
[0019] Preferably, the shroud is of thin wall construction, and
converges along at least part of its length from its head end to
its tail end, said convergence corresponding to the tapering of the
blade assembly.
[0020] The shroud, preferably, is of multi-section or unitary
moulded construction, having a head end section via which a flowing
fluid enters the shroud, a tail end section via which flowing fluid
exits the shroud, and an elongated intermediate section extending
between the head end section and the tail end section, with the
intermediate section converging from the head end section towards
the tail end section. Advantageously, the head end section of the
shroud converges towards the intermediate section, and the tail end
section diverges away from the intermediate section, such that the
shroud is generally in the form of a converging-diverging venturi
having a converging elongated throat defined by the intermediate
section.
[0021] Preferably, the shroud has a circular cross-sectional
profile, so that the head end section and the tail end section of
the shroud are flared in bell mouth fashion.
[0022] Each mounting formation preferably includes a bearing
element connected to an end section of the shaft, the bearing
elements in use being mounted on an anchored support structure,
such that the power generator assembly rotates relative to the
support structure.
[0023] In a further variation, the power generator assembly
includes a stator in front of the shroud, most preferably adjacent
the shroud head end section. The stator preferably includes one or
more blades of adjustable pitch.
[0024] In a yet variation, the power generator assembly includes a
slotted ejector arrangement behind the shroud, most preferably
adjacent the shroud tail end section. In one form, the slotted
ejector arrangement is connected to, and rotates with, the shroud.
In another form, the slotted ejector arrangement is not connected
to, and does not rotate with, the shroud. In one embodiment, the
slotted ejector arrangement includes a plurality of spaced apart
tubular sections, and most preferably diverges diametrically away
from the shroud. In another embodiment, the slotted ejector
arrangement is of unitary construction, with a helical slot
therein, and preferably diverges diametrically away from the
shroud. In one form, the assembly preferably includes a drive means
adapted to vary the axial length of the slotted ejector
arrangement. In another form, the assembly preferably includes a
drive means adapted to vary the axial length and radial width of
the slotted ejector arrangement.
[0025] In another aspect, the present invention provides an
electrical power generator assembly for using kinetic energy from a
flowing fluid to generate power, the electrical power generator
including:
[0026] a blade assembly having a head end for facing incoming
flowing fluid, a tail end spaced from the head end for facing in
the direction of the flowing fluid, and a rotational axis extending
between the head end and the tail end, the blade assembly including
a blade arrangement which includes a plurality of blades spaced
along the length of the rotation axis, and at least one mounting
formation connected to the blade arrangement, each mounting
formation being adapted to permit mounting of the blade assembly
for rotation about its rotational axis, so that in use fluid
flowing past the electrical power generator assembly interacts with
the blade arrangement to rotate the blade assembly about its
rotational axis; and
[0027] at least one primary coil connected to the blade arrangement
for rotation with the blade arrangement, the primary coil being
arranged in use to interact with at least one stationary secondary
coil to generate power in response to rotation of the blade
assembly.
[0028] Preferably, the features or components of the electrical
power generator according to this aspect of the invention, are
similar to those of the electrical power generator according to the
preceding aspect of the invention, when the blade arrangement of
such power generator includes a plurality of blades.
[0029] In a further aspect, the present invention provides an
electrical power generator installation, the installation
including:
[0030] an electrical power generator as hereinbefore described
including at least one secondary coil; and
[0031] a support structure, the electrical power generator being
mounted, by means of each mounting formation of the blade
arrangement, on the support structure for rotation of the blade
arrangement about its rotational axis, and each secondary coil of
the power generator being mounted on the mounting structure.
[0032] In the case of tidal energy or ocean stream power
generation, the power generator will be submerged in the ocean. In
the case of river flow power generation, the power generator will
be submerged in a river or flowing stream. In the case where the
flowing fluid with which the power generator is associated is wind,
the power generator will be located in an open area where it will
be exposed to flow of air when the wind blows.
[0033] In one embodiment, the support structure includes a network
of flexible elements, for example (heavy) chains or cables. The
network of flexible elements may be arranged such that the
generator can be aligned such that the inlet end of the shroud
opposes the direction of flow of the fluid, preferably so that it
aligns itself, in accordance with the direction of flow of a fluid.
In this embodiment, the network of flexible elements can,
preferably, be arranged such that the generator is mounted thereon
in the general fashion of a windsock. In another embodiment, the
support structure is a rigid structure including a network of rigid
elements.
[0034] In another aspect, the present invention provides a
propulsion or pump device adapted to eject a fluid, the propulsion
or pump device including:
[0035] a blade assembly having a head end for facing incoming
flowing fluid, a tail end spaced from the head end for facing in
the direction of the flowing fluid, and a rotational axis extending
between the head end and the tail end, the blade assembly including
a blade arrangement which is arranged in generally helical fashion
about the rotational axis, and at least one mounting formation
connected to the blade arrangement, each mounting formation being
adapted to permit mounting of the blade assembly for rotation about
its rotational axis, so that in use rotation of the blade assembly
about its rotational axis interacts with fluid flowing through the
electrical power generator assembly; and
[0036] at least one primary coil connected to the blade arrangement
for rotation with the blade arrangement, said at least one primary
coil being arranged in use to interact with at least one stationary
secondary coil to generate rotation of the blade assembly in
response to electrical power being applied to said at least one
stationary secondary coil.
BRIEF DESCRIPTION OF THE DRAWINGS
[0037] Preferred embodiments of the present invention will now be
described, by way of examples only, with reference to the
accompanying drawings wherein:
[0038] FIG. 1 is a schematic cross sectional view of a first
embodiment of a power generator;
[0039] FIG. 2 is a schematic cross sectional view of a second
embodiment of a power generator;
[0040] FIG. 3 is a schematic cross sectional view of a third
embodiment of a power generator;
[0041] FIG. 4 is a schematic cross sectional view of a fourth
embodiment of a power generator;
[0042] FIG. 5 is a schematic cross sectional view of a fifth
embodiment of a power generator;
[0043] FIG. 6 is a schematic cross sectional view of a sixth
embodiment of a power generator;
[0044] FIG. 7 is a schematic cross sectional view of a seventh
embodiment of a power generator;
[0045] FIG. 8 is a schematic cross sectional view of an eighth
sixth embodiment of a power generator; and
[0046] FIG. 9 is a schematic cross sectional view of a ninth
embodiment of a power generator.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0047] FIG. 1 shows schematically a first embodiment of an
electrical power generator assembly 10a, which is driven by the
kinetic energy of a flowing fluid 12, such as a tidal current,
ocean stream, river flow or wind, to generate electrical power. The
generator assembly 10a includes a blade assembly 14 with a head end
16 facing the oncoming flow of the fluid 12 and a tail end 18,
spaced from the head end 16, which faces in the direction of the
flow of the fluid 12.
[0048] The blade assembly 14 has a rotational axis 20 extending
between the head end 16 and the tail end 18. The blade assembly 14
also includes a mounting formation in the form of a shaft 24
supported by head end bearings 26 and tail end bearings 28. Stay
cables 36 and 38 are attached to the bearings 26 and 28
respectively, which locate the assembly 10a and resist movement of
the assembly 10a in the fluid flow 12.
[0049] The blade assembly 14 also has a blade arrangement, in the
form of a plurality, in this case, a pair, of equiangularly spaced
helical blades 44, and a generally frusto-conical shroud 50. Other
numbers of the equiangularly spaced helical blades (eg. 3, 4 or 5
etc) can also be used. The blades 44 reduce in diameter as they
wind around the shaft 24 from the head end 16 to the tail end 18
following the internal dimension of the shroud 50. The distal ends
of the blades 44 are also bonded to the interior surface of the
shroud 50. As a result, in use, the shroud 50 rotates with the
blades 44, which creates a vortex in front of the shroud 50.
[0050] The shroud 50 is of multi section construction having a head
end section 50a, via which the flowing fluid 12 enters the shroud
50, a tail end section 50b, via which the flowing fluid 12 exits
the shroud 50, and an elongated intermediate section 50c extending
between the head end section 50a and the tail end section 50b. The
intermediate section 50c also converges in diameter from the head
end section 50a towards the tail end section 50b. The head end
section 50a of the shroud 50 also converges towards the
intermediate section 50c and the tail end section 50b diverges away
from the intermediate section 50c such that the shroud 50 is
generally in the form of a converging-diverging venturi having a
converging elongated throat defined by the intermediate section
50c. At all points along is its length, the shroud 50 has a
circular cross-sectional profile. The shroud head end section 50a,
being shaped as a venturi, produces an area of low pressure behind
the blade assembly 14 which advantageously results in a much freer
flow of fluid through and exiting the shroud 50. Further, as the
shroud 50 is bonded to the blades 44, the shroud 50 rotates in
conjunction with the blades 44 and the rotational motion of the
shroud 50 induces a swirl or vortex in front of the shroud 50. This
vortex is advantageous as it models a whirlpool (as found in
nature) and sucks additional fluid into the blade assembly 14 than
would otherwise pass through it. The shroud 50 can also be of
unitary moulded construction, for increased strength.
[0051] The assembly 10a also includes a stator 100.
[0052] A series of primary coils 52 are integrated into the shroud
head end section 50a, by being wound around the extent of same. A
series of secondary coils 54a and secondary power coils 54b are
integrated into the stator 100.
[0053] In, use, the blade assembly 14 is mounted within the fluid
flow 12 which imparts its energy to the blades 44. As the fluid
flow 12 applies a force to the blades 44, the blades 44 react by
imparting a rotational force or torque to the shaft 24.
[0054] When a small excitation current 55 is applied to the
secondary coils 54a, a magnetic field 56 is created which induces a
current in the primary coils 52. The primary coils 52 then create a
magnetic field 57 which, together with the rotational motion of the
primary coils 52, induces a large current inside the secondary
power coils 54b that is connected for electricity generation
58.
[0055] Alternatively, the primary coils 52 can be replaced with
permanent magnets that create the magnetic field 57 and induce a
current in the secondary power coils 54b for electricity generation
58. In this configuration, the secondary coils 54a and the
excitation current 55 are not required.
[0056] Further alternatively, the excitation current 55 can be
applied to the primary coil 52. In this configuration, the
secondary coils 54a and the magnetic field 56 are not required.
[0057] The stay cables 36 and 38 are connected to a suitable
support structure installed in the ocean or alternatively, they can
be connected to a bridge or set of cables spanning an ocean inlet
or a set of support structures.
[0058] Alternative arrangements of the bearings 26 and 28 and the
stay cables 36 and 38 may be more suitable for other applications.
For example, in another embodiment (not shown), the bearing 26 can
be removed such that the bearing 28 is a single bearing to support
both the axial and radial forces of the shaft 24. The stay cables
38 can also be removed such that the assembly 10a is supported by
only the stay cables 36 and finds its own optimal alignment to flow
much like a windsock does. The assembly 10a can also be neutrally
buoyant and allowed to swing and change direction to operate on
incoming and outgoing tides.
[0059] Further alternatively, a current of different frequency can
be applied to the secondary coils 54a which in turn creates a
magnetic field to induce a current in the primary coils 52. The
induced current creates a magnetic field to interact with the
magnetic field from the secondary coils 54a to produce rotational
motion which in turn produces rotational motion of the blades 44
and provides thrust in the surrounding fluid to propel a craft or
pump a fluid. The frequency of the current applied to the secondary
coils 54a can be further adjusted so the assembly 10a acts as a
regenerative brake which is useful for slowing or stopping the
assembly 10a in adverse weather conditions.
[0060] FIG. 2 shows a second embodiment of an electrical power
generator assembly 10b. The assembly 10b is similar in construction
and operation to that shown in FIG. 1 and like reference numerals
to those used in the first embodiment shall be used to indicate
like features in FIG. 2.
[0061] In the assembly 10b, the blade assembly 14 comprises a
series of blades 44 arranged such that they create a helical
profile around the shaft 24. The primary coils 52 are integrated
into the blades 44 by being wound around the tips of the blades 44.
The primary coils 52 are in magnetic communication with the
secondary coils 54a and the secondary power coils 54b.
[0062] The fluid flow as depicted by the arrows 12 enters the
assembly 10b and imparts its energy to the blades 44. As the fluid
12 applies a force to the blades 44, the blades 44 react by
imparting a rotational force or torque to the shaft 24. The blades
44 can also be designed to direct the fluid 12 to flow radially
inward towards the shaft 24 so that minimal fluid is allowed to
escape the boundary of the assembly 10b, as defined by the
secondary coils 54a and the secondary power coils 54b.
[0063] When the small excitation current 55 is applied to the
secondary coils 54a, the magnetic field 56 is created which induces
a current in the primary coils 52. The primary coils 52 then create
the magnetic field 57 which, together with the rotational motion of
the primary coils 52, induces a large current inside the secondary
power coils 54b that is connected for electricity generation
58.
[0064] FIG. 3 shows a third embodiment of an electrical power
generator assembly 10c. The assembly 10c is similar in construction
and operation to those shown in FIGS. 1 and 2 and like reference
numerals to those used in describing the first and second
embodiments shall be used to indicate like features in FIG. 3.
[0065] In the assembly 10c, the blade assembly 14 has a blade
arrangement, in the form of a series of independent beams 22 which
are arranged in a generally helical fashion about the rotational
axis 20.
[0066] The beams 22 are connected to the shaft 24 with sufficient
clearance so they can rotated about the axis 20 with respect to
each other. The beams 22 are held in place at the head end 16 of
the shaft 24 via a flange (not shown) and, at the tail end 18, the
shaft 24 is threaded and a nut (not shown) is tightened to apply
force along the shaft 24 and lock the beams 22 in place.
Optionally, a skin or web 40 can be wound around the beams 22, the
skin 40 being able to expand and contract with the changing pitch
of the beams 22.
[0067] The length of each of the beams 22 decreases as they wind
around the shaft 24 from the head end 16 to the tail end 18 within
the generally frusto-conical boundary defined by the intermediate
section 50c of the shroud 50. The shroud is similar to that
described with reference to assembly 10a in FIG. 1.
[0068] In use, the blade assembly 14 is mounted within the fluid
flow 12 which imparts its energy to the skin 40 and beams 22. As
the fluid flow 12 applies a force to the beams 22, the beams 22
react by imparting a rotational force or torque to the shaft
24.
[0069] The beams 22 can also be configured to direct the fluid flow
12 radially inwards towards the shaft 24 in order to minimise fluid
escaping the boundary of the shroud 50. To do this, the beams 22,
when viewed in the direction of the axis 20, are twisted and
significantly curved inwards (in their direction of rotation) at
their ends to act like `cups` and direct the fluid flow towards the
axis 20. As the fluid flow 12 continues to flow through the blade
assembly 14, the cross sectional area of the flow decreases and its
pressure decreases. As its pressure decreases, the velocity of
fluid flow increases such is that a maximum amount of energy is
transferred from the fluid flow 12 to the beams 22. As a result,
the generator assembly 10a behaves like a reaction turbine, which
are normally associated with medium head flows rather than zero
head free flows. As the velocity of the fluid flow 12 changes, the
rotational alignment (ie. pitch) of the beams 22 can be altered in
order to operate the generator assembly 10 at maximum efficiency or
power output. This advantageously allows the turbine efficiency and
power output to be significantly increased for a range of flow
velocities.
[0070] The beams 22 include the primary coils 52 at their tips,
similar to that described with reference to the assembly 10b in
FIG. 2. The secondary coils 54a and the secondary power coils 54b
are also similar to that described with reference to the assembly
10b in FIG. 2, and are positioned external the shroud 50.
[0071] The fluid flow 12 enters the assembly 10c and imparts its
energy to the skin 40 and the beams 22. As the fluid 12 applies a
force to the beams 22, the beams 22 react by imparting a rotational
force or torque to the shaft 24.
[0072] When a small excitation current 55 is applied to the
secondary coils 54a, the magnetic field 56 is created which induces
a current in the primary coils 52. The primary coils 52 then create
the magnetic field 57 which, together with the rotational motion of
the primary coils 52, induces a large current inside the secondary
power coils 54b that is connected for electricity generation
58.
[0073] In the assembly 10c, the shroud 50 also includes vanes 90
installed on the leading edge of the shroud head end section 50a in
order to further increase the vortex induced in front of the shroud
50. This vortex is further aided by the increased velocity of the
tips of the beams 22 at the entry of the head end 16 of the blade
assembly 14 in creating suction pressure at the head end 16 of the
shroud 50. The combination of: decreased pressure inside the shroud
50; decreased pressure behind the shroud 50; the rotating shroud 50
inducing a vortex in front of the blade assembly 14; the flow vanes
90 inducing a vortex in front of the blade assembly 14; and the
smaller pitch of the blades at the entry of the blade assembly 14
results in substantially more fluid being sucked into the blade
assembly 14 than would otherwise occur. The increased fluid passing
through the blade assembly 14 dramatically increases the power
output of the assembly 10c.
[0074] FIG. 4 shows a fourth embodiment of an electrical power
generator assembly is 10d. Once again, like features to those
described with reference to earlier embodiments are denoted with
like reference numerals.
[0075] In the assembly 10d, the blades 44 are similar to that
described with reference to the assembly 10a in FIG. 1. The primary
coils 52 are also integrated into the shroud head end section 50a,
also similar to that described with reference to the assembly 10a
in FIG. 1. The primary coils 52 are in magnetic communication with
the secondary coils 54a and the secondary power coils 54b
integrated into the stator 100. The shroud 50 rotates with the
blades 44 and encompasses a half-set of magnetic bearings 60 that
are in magnetic communication with an opposing half-set of magnetic
bearings 62. The magnetic bearings 60 and 62 act as a set to repel
each other so that they allow rotation of the shroud 50, the blades
44 and the primary coils 52. The tapered shape of the magnetic
bearings 60 and 62 also allow them to act as a thrust bearing and
apply a force along the axis of rotation 20 towards the head end 16
to react against the drag force applied to the blades 44. The
magnetic bearings 60 and 62 are securely connected to the stator
100 by means of supports 64.
[0076] The fluid flow 12 enters the assembly 10c and imparts its
energy to the blades 44. As the fluid 12 applies a force to the
blades 44, the blades 44 react by imparting a rotational force or
torque to the shaft 24.
[0077] When a small excitation current 55 is applied to the
secondary coils 54a, the magnetic field 56 is created which induces
a current in the primary coils 52. The primary coils 52 then create
the magnetic field 57 which, together with the rotational motion of
the primary coils 52, induces a large current inside the secondary
power coils 54b that is connected for power generation 58.
[0078] The assembly 10d is held in a moving current by the stay
cables 36 and 38. The stay cables 36 and 38 are connected to a
suitable support structure installed in the ocean or alternatively,
they could be connected to a bridge or set of cables spanning an
ocean inlet or a set of support structures. Alternative
arrangements of the stay cables 36 and 38 may be more suitable for
other applications. For example, the exit stay cables 38 can also
be removed such that the assembly 10d is supported by only the stay
cables 36 and finds its own optimal alignment to flow much like a
windsock does. The assembly 10d can also be neutrally buoyant and
allowed to swing and change direction to operate on incoming and
outgoing tides.
[0079] FIG. 5 shows a fifth embodiment of an electric power
generator assembly 10e. Like features to those described with
reference to earlier embodiments are again denoted with like
reference numerals.
[0080] The assembly 10e is very similar in construction and
operation to the assembly 10a described with reference to FIG. 1
except that the primary coils 52 and the secondary coils 54a and
secondary power coils 54b are spaced radially apart rather than
axially, with the secondary coils 54a and secondary power coils 54b
on the outside of the primary coils 52. In this configuration, the
assembly 10d behaves more like a ring generator, as opposed to a
disc generator, and allows more space to integrate the coils. In an
alternative arrangement, the secondary coils 54a and secondary
power coils 54b are positioned on the inside of the primary coils
52.
[0081] FIG. 6 shows a sixth embodiment of an electric power
generator assembly 10f. Like features to those described with
reference to earlier embodiments are again denoted with like
reference numerals.
[0082] In the assembly 10f, the shaft 24 is hollow and includes
therein tapered roller bearings 70 around a solid structural beam
72, which is bonded to the stator 100 (or other stationary
structure). The bearings 70 allow the shaft 24 and the blades 44 to
rotate relative to the beam 72 as well as to react to the axial
thrust or drag forces on the assembly 10f. The blades 44 are
similar to that described with reference to the assembly 10a in
FIG. 1. The primary coils 52 are also integrated into the shroud
head end section 50a, and the secondary coil 54a and the secondary
power coil 54b are integrated into the stator, similar to that
described with reference to the assembly 10a in FIG. 1.
[0083] The assembly 10f also includes a slotted ejector arrangement
102 at the exit (ie. tail end section 50b) of the shroud 50. The
slotted ejector arrangement 102 is connected to the shroud 50 and
thus rotates with the shroud 50. The gaps 104 between spaced apart
sections 106 of the slotted ejector arrangement 102 allow fluid
flowing around the exterior of the assembly 10e to effectively
inject, as shown by arrows 108, into the fluid flow leaving the
shroud. The effect of this additional fluid 108 is it induces a
scavenging effect and increases the energy of the fluid leaving the
shroud and causes more fluid to pass through the interior of the
shroud 50, thereby improving the efficiency and power output of the
assembly 10e.
[0084] The fluid flow as depicted by the arrows 12 enters the
assembly 10b and imparts its energy to the blades 44. As the fluid
12 applies a force to the blades 44, the blades 44 react by
imparting a rotational force or torque to the shaft 24.
[0085] When a small excitation current 55 is applied to the
secondary coils 54a, a magnetic field 56 is created which induces a
current in the primary coils 52. The primary coils 52 then create a
magnetic field 57 which, together with the rotational motion of the
primary coils 52, induces a large current inside the secondary
power coils 54b that is connected for power generation 58.
[0086] Alternatively, the primary coils 52 can be replaced with
permanent magnets that create the magnetic field 57 and induce a
current in the secondary power coils 54b for electricity generation
58. In this configuration, the secondary coils 54a and the
excitation current 55 are not required.
[0087] The stay cables 36 and 38 are connected to a suitable
support structure installed in the ocean or alternatively, they can
be connected to a bridge or set of cables spanning an ocean inlet
or a set of support structures. Alternative arrangements of the
stay cables 36 and 38 may be more suitable for other applications.
For example, the exit stay cables 38 can also be removed such that
the assembly 10f is supported by only the stay cables 36 and finds
its own optimal alignment to flow much like a windsock does. The
assembly 10d can also be neutrally buoyant and allowed to swing and
change direction to operate on incoming and outgoing tides.
[0088] Alternatively a current of different frequency can be
applied to the secondary power coils 54b which in turn creates a
magnetic field to induce a current in the primary coils 52. The
induced current creates a magnetic field to interact with the
magnetic field from the secondary coils 54a to produce rotational
motion which in turn produces rotational motion of the blades 44
and provides thrust in the fluid 12 to propel a craft or pump a
fluid. The frequency of the current applied to the secondary power
coils 54b can be further adjusted so the turbine acts as a
regenerative brake which is useful for slowing or stopping the
turbine in adverse weather conditions.
[0089] FIG. 7 shows a seventh embodiment of an electric power
generator assembly 10g. Like features to those described with
reference to earlier embodiments are again denoted with like
reference numerals. The assembly 10g is similar in construction and
operation to the assembly 10f described with reference to FIG.
6.
[0090] The slotted ejector arrangement 102 is connected to the
shroud 50 and thus rotates with the shroud 50. However, in the
assembly 10f, the slotted ejector arrangement 102 is of unitary
construction with a single helical slot forming the gaps 104
between the sections 106. It should be noted that the length of the
slotted ejector 102 can be adjusted to change the width of the
slots 104 to vary the effect of injection and power output. By
changing the length of the ejector, the width of the slots 22 can
be altered and the power output adjusted. A drive device, in the
form of a hydraulic ram 80 is connected to the structural beam 72.
The drive device can alternatively be a worm gear arrangement. A
hydraulic cylinder 82 is connected to one end of the ram 80 and
used to extend or contract the ram 80. The other end of the ram 80
is connected to the most outwardly ejector ring 108, via supports
84 and a pivot 86. As the ram 80 extends, it applies a force on the
pivot 86, the supports 84 and the (end) ring 108, such that the
ejector arrangement 102 increases in length (and reduces in
diameter). To contract (and widen) the ejector arrangement 102, a
reverse force is applied using the ram 80.
[0091] For example, the assembly 10f can be installed with a longer
slotted ejector arrangement 102 in slow flows to draw more water
through and increase power output. In fast currents, a shorter
slotted ejector arrangement 102 can be utilised. The helical
slotted ejector arrangement 102 can also be constructed from an
elastic material such as aluminium so it can vary its shape
depending on the force applied to it from the strength of the water
flow.
[0092] FIG. 8 shows an eighth embodiment of an electric power
generator assembly 10h. Like features to those described with
reference to earlier embodiments are again denoted with like
reference numerals. The assembly 10g is similar in construction and
operation to the assembly 10g described with reference to FIG.
7.
[0093] However, in the assembly 10h, the slotted ejector
arrangement 102 is not connected to the shroud 50 and does not
rotate with the shroud 50. The slotted ejector arrangement 102 is
instead connected to an extension 72' of the structural beam 72 via
the supports 84 and thus remains stationary whilst the shroud 50
rotates.
[0094] FIG. 9 shows a ninth embodiment of an electric power
generator assembly 10i. Like features to those described with
reference to earlier embodiments are again denoted with like
reference numerals. The assembly 10i is similar in construction and
operation to the assembly 10g described with reference to FIG.
7.
[0095] However, in the assembly 10i, the slotted ejector
arrangement 102 is again not connected to the shroud 50 and does
not rotate with the shroud 50. Further, the ram 80 does not rotate
relative to the structural beam 72. The slotted ejector arrangement
102 is instead connected to the structural beam 72 via the supports
84 and the pivot 86 and thus remains stationary whilst the shroud
50 rotates.
[0096] The hydraulic cylinder 82 connected to one end of the ram 80
can be used to extend or contract the ram 80. As the ram 80
extends, it applies a force on the pivot 86, the supports 84 and
the (end) ring 106, such that the ejector arrangement 102 increases
in length (and narrows in diameter). To contract (and widen) the
ejector arrangement 102, a reverse force is applied using the ram
80. Further, if the pivot 86 is replaced with a fixed connector,
then extending the ram 80 only increases the length of the ejector
arrangement. Similarly, a reverse force on the ram 80 only
contracts the ejector arrangement 102.
[0097] Although the invention has been described with reference to
preferred embodiments, it would be appreciated by persons skilled
in the art that the invention may be embodied in many other
forms.
* * * * *