US20110158787A1 - Wind turbine - Google Patents
Wind turbine Download PDFInfo
- Publication number
- US20110158787A1 US20110158787A1 US13/039,951 US201113039951A US2011158787A1 US 20110158787 A1 US20110158787 A1 US 20110158787A1 US 201113039951 A US201113039951 A US 201113039951A US 2011158787 A1 US2011158787 A1 US 2011158787A1
- Authority
- US
- United States
- Prior art keywords
- shroud
- assembly
- turbine
- wind
- turbine assembly
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 230000000712 assembly Effects 0.000 claims abstract description 98
- 238000000429 assembly Methods 0.000 claims abstract description 98
- 238000000034 method Methods 0.000 claims abstract description 12
- 230000008859 change Effects 0.000 claims description 17
- 230000004044 response Effects 0.000 claims description 9
- 238000004519 manufacturing process Methods 0.000 abstract description 2
- 238000010248 power generation Methods 0.000 description 13
- 239000012530 fluid Substances 0.000 description 8
- 230000033001 locomotion Effects 0.000 description 6
- 230000002093 peripheral effect Effects 0.000 description 6
- 229910052782 aluminium Inorganic materials 0.000 description 4
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 4
- 239000002131 composite material Substances 0.000 description 4
- 230000007423 decrease Effects 0.000 description 4
- 230000003247 decreasing effect Effects 0.000 description 4
- 238000013461 design Methods 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 230000008901 benefit Effects 0.000 description 3
- 230000005540 biological transmission Effects 0.000 description 3
- 238000009826 distribution Methods 0.000 description 3
- 230000005611 electricity Effects 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 239000004033 plastic Substances 0.000 description 3
- 229920003023 plastic Polymers 0.000 description 3
- 150000001721 carbon Chemical class 0.000 description 2
- 238000004891 communication Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 238000012546 transfer Methods 0.000 description 2
- 241000283690 Bos taurus Species 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 239000004698 Polyethylene Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 150000001722 carbon compounds Chemical class 0.000 description 1
- 239000003245 coal Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 238000013016 damping Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000009977 dual effect Effects 0.000 description 1
- RLQJEEJISHYWON-UHFFFAOYSA-N flonicamid Chemical compound FC(F)(F)C1=CC=NC=C1C(=O)NCC#N RLQJEEJISHYWON-UHFFFAOYSA-N 0.000 description 1
- 239000002803 fossil fuel Substances 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 239000000295 fuel oil Substances 0.000 description 1
- 230000003116 impacting effect Effects 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 238000011031 large-scale manufacturing process Methods 0.000 description 1
- 239000003562 lightweight material Substances 0.000 description 1
- 244000144972 livestock Species 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 239000003345 natural gas Substances 0.000 description 1
- 239000003758 nuclear fuel Substances 0.000 description 1
- 238000013021 overheating Methods 0.000 description 1
- -1 polyethylene Polymers 0.000 description 1
- 229920000573 polyethylene Polymers 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 230000008439 repair process Effects 0.000 description 1
- 238000012421 spiking Methods 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 239000003643 water by type Substances 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03D—WIND MOTORS
- F03D13/00—Assembly, mounting or commissioning of wind motors; Arrangements specially adapted for transporting wind motor components
- F03D13/20—Arrangements for mounting or supporting wind motors; Masts or towers for wind motors
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03D—WIND MOTORS
- F03D3/00—Wind motors with rotation axis substantially perpendicular to the air flow entering the rotor
- F03D3/04—Wind motors with rotation axis substantially perpendicular to the air flow entering the rotor having stationary wind-guiding means, e.g. with shrouds or channels
- F03D3/0436—Wind motors with rotation axis substantially perpendicular to the air flow entering the rotor having stationary wind-guiding means, e.g. with shrouds or channels for shielding one side of the rotor
- F03D3/0472—Wind motors with rotation axis substantially perpendicular to the air flow entering the rotor having stationary wind-guiding means, e.g. with shrouds or channels for shielding one side of the rotor the shield orientation being adaptable to the wind motor
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03D—WIND MOTORS
- F03D7/00—Controlling wind motors
- F03D7/02—Controlling wind motors the wind motors having rotation axis substantially parallel to the air flow entering the rotor
- F03D7/0204—Controlling wind motors the wind motors having rotation axis substantially parallel to the air flow entering the rotor for orientation in relation to wind direction
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03D—WIND MOTORS
- F03D80/00—Details, components or accessories not provided for in groups F03D1/00 - F03D17/00
- F03D80/70—Bearing or lubricating arrangements
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03D—WIND MOTORS
- F03D9/00—Adaptations of wind motors for special use; Combinations of wind motors with apparatus driven thereby; Wind motors specially adapted for installation in particular locations
- F03D9/20—Wind motors characterised by the driven apparatus
- F03D9/25—Wind motors characterised by the driven apparatus the apparatus being an electrical generator
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P9/00—Arrangements for controlling electric generators for the purpose of obtaining a desired output
- H02P9/04—Control effected upon non-electric prime mover and dependent upon electric output value of the generator
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05B—INDEXING SCHEME RELATING TO WIND, SPRING, WEIGHT, INERTIA OR LIKE MOTORS, TO MACHINES OR ENGINES FOR LIQUIDS COVERED BY SUBCLASSES F03B, F03D AND F03G
- F05B2240/00—Components
- F05B2240/90—Mounting on supporting structures or systems
- F05B2240/91—Mounting on supporting structures or systems on a stationary structure
- F05B2240/911—Mounting on supporting structures or systems on a stationary structure already existing for a prior purpose
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05B—INDEXING SCHEME RELATING TO WIND, SPRING, WEIGHT, INERTIA OR LIKE MOTORS, TO MACHINES OR ENGINES FOR LIQUIDS COVERED BY SUBCLASSES F03B, F03D AND F03G
- F05B2270/00—Control
- F05B2270/30—Control parameters, e.g. input parameters
- F05B2270/32—Wind speeds
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05B—INDEXING SCHEME RELATING TO WIND, SPRING, WEIGHT, INERTIA OR LIKE MOTORS, TO MACHINES OR ENGINES FOR LIQUIDS COVERED BY SUBCLASSES F03B, F03D AND F03G
- F05B2270/00—Control
- F05B2270/30—Control parameters, e.g. input parameters
- F05B2270/321—Wind directions
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
- H02P2101/00—Special adaptation of control arrangements for generators
- H02P2101/15—Special adaptation of control arrangements for generators for wind-driven turbines
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B10/00—Integration of renewable energy sources in buildings
- Y02B10/30—Wind power
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
- Y02E10/728—Onshore wind turbines
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
- Y02E10/74—Wind turbines with rotation axis perpendicular to the wind direction
Definitions
- the present invention is directed to wind turbine systems and methods. More particularly, the present invention relates to wind turbine systems and methods that utilize counter-rotating turbine assemblies.
- wind turbine systems have been developed for generating power at or near the point of use.
- such systems have typically had only modest power generation capabilities, thereby limiting their application to the useful generation of power.
- such systems have been utilized for low power applications, such as charging batteries and direct current (DC) applications.
- DC direct current
- deployment of such systems has typically been limited to remote locations, where electrical power may otherwise be unavailable, as opposed to being deployed as an alternate energy source where grid power is otherwise available. Therefore, the use of wind generated electrical power at or near the point of use, on a scale at which the sale of electricity to an electric utility during times when the wind generated power is not entirely consumed at the location, has been limited.
- a wind turbine system having first and second turbine assemblies.
- the first and second turbine assemblies are configured to rotate about a first axis, in opposite directions, in the presence of a suitable wind.
- first and second shroud assemblies are associated with the first and second wind turbine assemblies respectively.
- the first and second shroud assemblies extend around the outer circumference of the corresponding first and second turbine assemblies.
- the shroud assemblies include shroud members that extend around some portion of the outer circumference of the respective turbine assembly.
- the first turbine assembly is interconnected to a first drive shaft having an axis of rotation that is coincident with the first axis of the system.
- the second turbine assembly is interconnected to a second drive shaft that has an axis of rotation that also is coincident with the first axis of the system.
- at least a portion of the second drive shaft can be received by and rotate within the first drive shaft.
- the first and second drive shafts are part of a drive train assembly that can operate to transfer wind energy from the turbine assemblies to a generator.
- a wind turbine system in accordance with embodiments of the present invention can include a base member to which the turbine assemblies and the shroud assemblies are interconnected, either directly or through other components.
- the first shroud assembly can be interconnected to the base member, and the second shroud assembly can in turn be interconnected to the first shroud assembly.
- the first shroud assembly can be selectively positioned by rotating the first shroud assembly about the first axis of the system and relative to the base member.
- the second shroud assembly can be selectively positioned by rotating the second shroud assembly about the first axis of the system relative to the base member and the first shroud assembly.
- the first and second shroud assemblies can comprise a support structure that at least partially supports one or both of the turbine assemblies.
- first drive shaft of the first wind turbine assembly can be rotatably interconnected to the base member.
- the second drive shaft of the second wind turbine assembly can also be rotatably interconnected to the base member.
- bearings can rotatably interconnect the first and second drive shafts.
- one or both of the first and second drive shafts can be interconnected to a support structure comprising one or both of the shroud assemblies.
- Methods in accordance with embodiments of the present invention include providing counter-rotating turbine assemblies.
- the turbine assemblies are selectively exposed to the wind through operation of shroud assemblies. More particularly, the shroud assemblies are rotated about a first axis of the system to expose a portion of a corresponding wind turbine assembly to the wind, while shielding another portion of that wind turbine assembly from the wind.
- the shroud assemblies can thus be used to control the exposure of the turbine assemblies to the wind so that the turbine assemblies are driven in a desired direction and to control the force of the wind on the turbine assemblies.
- the shroud assemblies can be positioned to entirely or substantially shield the turbine assemblies, for example where the generation of power is not desired, or to protect the wind turbine system from extremely strong winds.
- FIG. 1 depicts a wind turbine system in accordance with embodiments of the present invention in an exemplary operating environment
- FIG. 2 is a block diagram depicting components of a wind turbine system in accordance with embodiments of the present invention
- FIG. 3 is a front view in elevation of a wind turbine system in accordance with embodiments of the present invention.
- FIG. 4 is a perspective view of a wind turbine system in accordance with embodiments of the present invention.
- FIG. 5 is a perspective view of wind turbine system support structure components in accordance with embodiments of the present invention.
- FIG. 6A is a top perspective view of a first turbine assembly in accordance with embodiments of the present invention.
- FIG. 6B is a top plan view of a first turbine assembly in accordance with embodiments of the present invention.
- FIG. 6C is a view in elevation of a first turbine assembly in accordance with embodiments of the present invention.
- FIG. 7A is a top perspective view of a second turbine assembly in accordance with embodiments of the present invention.
- FIG. 7B is a top plan view of a second turbine assembly in accordance with embodiments of the present invention.
- FIG. 7C is a view in elevation of a second turbine assembly in accordance with embodiments of the present invention.
- FIG. 8A is a front perspective view of a turbine assembly blade in accordance with embodiments of the present invention.
- FIG. 8B is a side elevation of a turbine assembly blade in accordance with embodiments of the present invention.
- FIG. 8C is a first end view of a turbine assembly blade in accordance with embodiments of the present invention.
- FIG. 8D is a second end view of a turbine assembly blade in accordance with embodiments of the present invention.
- FIG. 9A depicts a portion of a turbine assembly in accordance with embodiments of the present invention.
- FIG. 9B is a plan view of a turbine assembly with a blade that has been displaced in accordance with embodiments of the present invention.
- FIG. 10 is a cross-section of a compliance unit in accordance with embodiments of the present invention.
- FIG. 11A depicts a wind turbine system in accordance with embodiments of the present invention, and illustrates shroud member positions in an exemplary operating environment
- FIG. 11B depicts the shroud member positions of FIG. 11A in plan view
- FIG. 12A depicts a wind turbine system in accordance with embodiments of the present invention, and illustrates shroud member positions in another operating environment
- FIG. 12B depicts the shroud member positions of FIG. 12A in plan view
- FIG. 13A depicts a wind turbine system in accordance with embodiments of the present invention, and illustrates shroud member positions in another operating environment;
- FIG. 13B depicts the shroud member positions of FIG. 13A in plan view
- FIG. 14A depicts a wind turbine system in accordance with embodiments of the present invention, and illustrates shroud member positions in another operating environment
- FIG. 14B depicts the shroud member positions of FIG. 14A in plan view
- FIG. 15A depicts a wind turbine system in accordance with embodiments of the present invention, and illustrates shroud member positions in another operating environment
- FIG. 15B depicts the shroud member positions of FIG. 15A in plan view
- FIG. 16A depicts a wind turbine system in accordance with embodiments of the present invention, and illustrates shroud member positions in another operating environment
- FIG. 16B depicts the shroud member positions of FIG. 16A in plan view
- FIG. 17 is a flowchart depicting aspects of the operation of a wind turbine system 104 in accordance with embodiments of the present invention, and in particular operation while the wind turbine system 104 is in a power generation mode.
- FIG. 1 depicts a wind turbine system 104 in accordance with embodiments of the present invention, in an exemplary operating environment.
- the wind turbine system 104 is shown mounted to a platform 108 .
- the platform 108 comprises a tall building
- the wind turbine system 104 is mounted to the roof of that building 108 .
- a wind turbine system 104 in accordance with embodiments of the present invention can be associated with any type of platform 108 . Therefore, examples of suitable platforms 108 to which a wind turbine system 104 as disclosed herein can be mounted include, in addition to tall buildings such as skyscrapers, mid-rise buildings, warehouses, big box retail stores, residences, towers, storage tanks, bridges or platforms.
- a wind turbine system 104 can be mounted in alternate orientations.
- a wind turbine system 104 can be mounted in a horizontal orientation, for instance to the side of a platform 108 comprising a building or tower.
- a wind turbine system 104 in accordance with embodiments of the present invention can be mounted in an upside down vertical orientation, for example to the underside of a bridge.
- FIG. 2 is a block diagram depicting components of a wind turbine system 104 in accordance with embodiments of the present invention.
- the wind turbine system 104 can include a number of shroud assemblies 204 .
- a wind turbine system 104 can include a first shroud assembly 204 a and a second shroud assembly 204 b.
- each shroud assembly 204 is associated with and can at least partially define a volume containing a turbine assembly 208 .
- a wind turbine system 104 can include a first turbine assembly 208 a and a second turbine assembly 208 b.
- the turbine assemblies 208 can be coupled to an electrical generator 212 by a drive train assembly 216 .
- the component of the wind turbine system 104 used to generate electricity may comprise a motor operated as an electrical generator.
- the generator 212 may comprise a 60 Hz 3 phase permanent magnet generator.
- the drive train assembly 216 can include drive shafts that interconnect the turbine assemblies 208 to an input shaft of the generator 212 via a clutch.
- the generator 212 can comprise any electrical generator.
- the wind turbine system 104 can also include a shroud control system 220 .
- the shroud control system 220 can comprise motors, sensors, and controllers or processors for determining and controlling the position of the shroud assemblies 204 .
- FIG. 3 depicts a wind turbine system 104 in accordance with embodiments of the present invention in elevation.
- the wind turbine system 104 is mounted to a base member 304 that is in turn mounted to the platform 108 .
- the base member 304 includes a bottom plate or first end surface 308 and a top plate or second end surface 312 .
- top and bottom are used throughout the specification for ease of description, it should be appreciated that the wind turbine system 104 can be oriented such that the bottom surface is above the top surface, or is at the same elevation or average elevation above the ground as the top surface, depending on the orientation of the wind turbine system 104 .
- a bottom surface, member or other element refers to an instance of the associated component or assembly that is more proximal to the platform 108 or the base member 304 than is a top component or assembly.
- the bottom plate or first end surface 308 can comprise a first circular end surface
- the top plate or second end surface 312 can comprise a second circular end surface.
- the base member 304 includes an intermediate section 316 having a diameter that is less than the diameter of the first circular end surface 308 and the second circular end surface 316 . Accordingly, the base member 304 can have a profile that is tapered in the center.
- the first shroud assembly 204 a is mounted to the base member 304 via a first circular track or peripheral bearing assembly 320 .
- the first peripheral bearing assembly 320 allows the first shroud assembly 204 a to be rotated relative to the base member 304 about a first or system axis 324 .
- a first central bearing assembly 328 can also be provided to rotatably interconnect the first shroud assembly 204 a to the base member 304 and/or a first drive shaft 332 .
- the second shroud assembly 204 b is interconnected to the first shroud assembly 204 a via a second circular track or equatorial bearing assembly 336 .
- the equatorial bearing assembly 336 allows the second shroud assembly 204 b to be rotated about the system axis 324 relative to the base member 304 , and relative to an independently of the first shroud assembly 204 a.
- a second central bearing assembly 340 can also be provided to rotatably interconnect the second shroud assembly 204 b to a second drive shaft 344 .
- Sensors comprising position encoders can be associated with or incorporated into some or all of the bearing assemblies 320 , 328 , 336 and 340 , to provide information to a controller of the shroud control system 220 regarding the positions of the shroud assemblies 304 about the system axis 324 .
- Each of the shroud assemblies 204 includes a shroud member 348 .
- a first shroud member 348 a associated with the first shroud assembly 204 a generally extends between the first peripheral bearing assembly 320 and the hemispherical bearing assembly 336 .
- the first shroud member 348 a is mounted to the first shroud assembly 204 a via the first peripheral bearing assembly 320 and the equatorial bearings assembly 336 , and thus can be rotated relative to the system or central axis 124 and the first shroud assembly 204 a by moving the shroud member 348 a along the bearing assemblies 320 and 336 .
- first shroud member 348 a is generally hemispherical in that it extends for about one half the outer circumference of the first shroud assembly 204 a.
- the second shroud assembly 348 b generally extends between the hemispherical bearing 336 to or near a top extent of the wind turbine system 104 .
- the second shroud member 348 b is mounted to the second shroud assembly 204 b via a second peripheral bearing assembly 322 and the equatorial bearing assembly 336 , and can be rotated relative to the central axis 124 and the second shroud assembly 204 b by moving the shroud member 348 b along the bearing assembly 322 and 336 .
- the second shroud member 358 b is generally hemispherical in that it extends around about one half the outer circumference of the second shroud assembly 204 b.
- the shroud assemblies 204 together define a shape that is generally spherical.
- the shroud assemblies 204 also generally describe a partially enclosed volume comprising a housing for the turbine assemblies 208 .
- the first shroud assembly 204 a partially encloses the first turbine assembly 208 a.
- the second shroud assembly 204 b partially encloses the second turbine assembly 208 b.
- the rotational locations about the system axis 324 that are enclosed by the shroud members 348 of the shroud assemblies 204 are controlled to provide a desired operational state of the wind turbine system 104 , as described elsewhere herein.
- shroud assemblies 204 can be effected through the actuation of motors, such as stepper motors, associated with or incorporated into some or all of the bearings 320 , 328 , 336 , and 340 .
- motors such as stepper motors
- embodiments of the present invention include turbine assemblies 208 that each comprise a plurality of airfoils or blades 352 having a first surface 804 and a second surface 808 .
- the blades 352 of the first turbine assembly 208 a are oriented to rotate that assembly 208 a in a first direction about the system axis 324
- the blades 352 of the second turbine assembly 208 b are oriented to rotate that assembly 208 b in a second direction about the system axis 324
- the first turbine assembly 208 a may have a first number of blades 352
- the second turbine assembly 208 b may have a second, different number of blades 352 .
- the turbine assemblies 208 are asynchronous in operation.
- Each of the blades 352 of the first turbine assembly 208 a can be interconnected to the first drive shaft 332 by a blade support structure 356 .
- each of the blades 352 of the second turbine assembly 208 b can be interconnected to the second drive shaft 344 by a blade support structure 356 .
- the blade support structure 356 can include one or more struts, although other configurations are possible.
- FIG. 4 is a perspective view of a wind turbine system 104 in accordance with embodiments of the present invention. More particularly, FIG. 4 illustrates the relationship of a wind turbine system 104 to a prevailing wind 404 and flow paths through the wind turbine system 104 under exemplary operating conditions. In FIG. 4 , the shroud assemblies 204 are shown positioned such that about a 90° section or arc of each of the turbine assemblies 208 is exposed to face the wind 404 .
- the shroud assemblies 204 are positioned so that the wind is incident on the first side or surface 804 of the blades 352 of the turbine assemblies 208 , and to allow the wind 404 to apply a generally tangential force on the turbine assemblies 208 such that the turbine assemblies 208 rotate in opposite directions about the system axis 324 .
- the resulting exposure of the turbine assemblies 208 to the incident wind 404 causes the first turbine assembly 208 b to be rotated in a clockwise direction about the system axis 324 , and causes the second turbine assembly 208 b to be rotated in a counter-clockwise direction, when the wind turbine system 104 is viewed from above.
- the wind turbine system 104 provides a stepper or dual compressor effect with respect to at least some of the incident wind 404 .
- the blades 352 of the first turbine assembly 208 a generally direct at least some of the wind incident thereon upwards through the wind turbine system 104 , to the second turbine assembly 204 b. Therefore, in addition to the wind 404 that is directly incident on the blades 352 of the second turbine assembly 208 b, at least some wind that was incident on the blades 352 of the first turbine assembly 204 a is available to also act on the blades 352 of the second turbine assembly 208 b.
- the counter-rotation of the first 208 a and second 208 b turbine assemblies results in a small or even zero torsional force on an associated platform 108 .
- the counter-rotating turbine assemblies 208 can provide reduced vibration characteristics as compared to systems that do not employ counter rotating turbine assemblies or elements that are asynchronous due to having differing numbers of blades or airfoils.
- the first turbine assembly 208 a may have a larger number of blades than the second turbine assembly 208 b.
- the flow paths of the wind 404 through the turbine assemblies 208 and the movement of the turbine assemblies 208 in a direction that is generally away from the incident wind 404 can provide a safer environment for birds and other wildlife.
- FIG. 5 is a perspective view of components of a support structure 504 of a wind turbine system in accordance with embodiments of the present invention.
- FIG. 5 illustrates the generally spherical volume or truncated spherical volume defined by the shroud assemblies 204 .
- the support structure 504 can include the base member 304 , the first shroud assembly 204 a, and the second shroud assembly 204 b. Additional details of embodiments of the shroud assemblies 204 are also illustrated.
- each shroud assembly 204 includes an equatorial support member 508 .
- each shroud assembly 204 can include a number of longitudinal support members 510 .
- each shroud assembly 204 can include four longitudinal support members 510 spaced at 90° intervals.
- each shroud assembly 204 can include radial members 514 that extend between the equatorial support member 508 and a center ring 518 of the associated shroud assembly 204 . It can also be seen that, at least in some embodiments of the disclosed invention, the support for the second shroud assembly 204 b can be entirely or primarily provided by the first shroud assembly 204 a.
- each shroud assembly 204 can include a web structure 512 .
- the web structure 512 provides support for a corresponding shroud assembly 204 , at an end of that shroud assembly 204 opposite the equatorial support member 508 , and also provides support for longitudinal support members 510 that extend between the web structure 512 and the equatorial support member 508 .
- the web structure 512 a associated with the first shroud assembly 204 a can also include or can be proximate to a portion of the peripheral bearing assembly 320 associated with the first shroud assembly 204 a, and/or the central bearing assembly 328 .
- the web structure 512 b associated with the second shroud assembly 204 b can function to provide additional support for the second shroud member 348 b.
- the second web structure 512 b can include or be associated with a portion of the bearing assembly 340 .
- FIG. 5 also illustrates an access panel 516 in the base member 304 .
- the access panel 516 can be used to access the generator 212 and/or other wind turbine system 104 components housed within the base member 304 .
- the shroud members 348 can be rotated around the central axis 324 relative to the associated shroud assembly 204 support members and structures.
- each shroud member 348 can be mounted to the remainder of the wind turbine system 104 by the equatorial bearing assembly 336 and by end bearings 518 interconnected to the web structure 512 of the associated shroud assembly 204 .
- FIGS. 6A-6C illustrate top perspective, top plan, and elevation views respectively of a first turbine assembly 208 a in accordance with embodiments of the present invention.
- the first turbine assembly 208 a includes a plurality of airfoils or blades 352 .
- eight blades 352 are shown.
- the number of blades 352 in a particular embodiment will depend on the design of the individual airfoils 352 and other considerations. For instance, it is desirable to maintain a spacing between blades 352 that is sufficient to allow the individual blades 352 to operate efficiently.
- a blade 352 can function as a lifting body through at least some portion of the rotation of the turbine assembly 208 .
- a blade 352 will act as a lifting body as it comes from behind the shroud member 348 and enters the air flow or wind, and for some additional degrees of rotation of the turbine assembly 208 . Therefore, it is desirable to maintain a spacing between blades 352 that is large enough to allow each blade 352 to generate lift without being negatively impacted by turbulence from adjacent blades 352 . Moreover, the blades 352 can be spaced such that as the angle of attack of a blade 352 increases and the blade 352 begins to spill wind, that spilled wind is directed towards and impacts a downwind blade 352 .
- the blade 352 has advanced to a point that the blade 352 is more normal to the wind, it is beneficial to maintain spacing between the blades 352 that is large enough to allow the wind to impact the blade 352 unimpeded or relatively unimpeded by the next blade 352 .
- the benefits of maintaining space between blades 352 is generally balanced against the additional force that can be extracted from wind of a given velocity by having a larger number of blades 352 exposed to the wind at a particular moment in time.
- Each blade 352 in the illustrated example is interconnected to the first drive shaft 332 by a support structure 356 comprising a plurality of support struts 604 . From the views in FIGS. 6A-6C , it can be appreciated that the blades 352 are shaped to be effective to rotate the first drive shaft 335 when a portion of the wind turbine assembly 208 is exposed to an incident wind with a component that is generally tangential to an outer circumference of the turbine assembly 208 a. In particular, the blades 352 of the first wind turbine assembly 208 a are configured to rotate the first drive shaft 335 in a clockwise direction, when the first wind turbine assembly 204 a is viewed from above, and when exposed to such an incident wind.
- the blades 352 can be configured to direct at least some wind incident on the blades 352 in an end to end (e.g., a bottom to top) direction.
- the outer edges 812 can be contoured so that the overall profile of the blade portion of the first turbine assembly 208 a is hemispherical or hemispherical-like.
- FIGS. 7A-7C illustrate a second turbine assembly 208 b in accordance with embodiments of the present invention in top perspective, top plan and elevation views respectively.
- the second turbine assembly 208 b includes a plurality of airfoils or blades 352 .
- the blades 352 of the second turbine assembly 208 b are interconnected to the second drive shaft 344 by a support structure 356 .
- the support structure 356 includes a plurality of support struts 604 associated with each blade 352 .
- the blades 352 are configured to rotate the second drive shaft 344 in a counterclockwise direction when the second turbine assembly 208 b is viewed from above, in the presence of an incident wind having a component that is generally tangential to an outer circumference of the turbine assembly 208 a.
- the blades 352 are configured to impart a rotational force to the second drive shaft 344 in a counterclockwise direction in response to an updraft of wind (or a bottom to top flow generally parallel to the system axis 324 ), such as may be provided by a first turbine assembly 208 a in a wind turbine system 104 configured as illustrated in, for example, FIGS. 3 and 4 .
- At least a portion of the wind incident on the second turbine assembly 208 b can be exhausted in an upward direction (or in a direction generally parallel to the system axis 324 ).
- the outer edges 812 of the blades 352 can be contoured so that the overall profile of the blade portion of the second turbine assembly 208 b is hemispherical or hemispherical-like.
- first turbine assembly 208 a of FIGS. 6A-6C seven blades 352 are shown, while in the example second turbine assembly 208 b of FIGS. 7A-7C , six blades 352 are shown.
- the number of blades 352 in the turbine assemblies 208 of a particular embodiment of a wind turbine system 104 in accordance with the present invention will vary depending on the particular application and design considerations for example as described above in connection with the first turbine assembly 208 a.
- the first 208 a and second 208 b turbine assemblies each have a different number of blades 352 .
- the first turbine assembly 208 a has a larger number of blades 352 than the second turbine assembly 208 b.
- vibration and noise produced during operation of the wind turbine system 104 can be reduced as compared to embodiments in which the first 208 a and second 208 b turbine assemblies have the same number of blades 352 .
- FIGS. 8A-8D provide different views of a blade 352 of a turbine assembly 204 in accordance with embodiments of the present invention.
- FIG. 8A is a perspective view
- FIG. 8B is a side elevation
- FIG. 8C is a first plan view
- FIG. 8D is a second plan view of an exemplary blade 352 in accordance with embodiments of the present invention.
- the blade 352 includes a first surface 804 that is cupped or profiled to capture wind incident on that surface 804 .
- the blades 352 can comprise lifting bodies. Therefore, a wind turbine system 104 can comprise both impulse turbine and reaction turbine operating principles.
- a wind system 104 in accordance with embodiments of the present invention generally positions the shroud members 348 such that the wind is allowed to be incident on the first surface 804 of the turbine assembly 208 blades 352 .
- each blade 352 has a second surface 808 that is relatively streamlined such that, to the extent the blade 352 travels in a direction away from the first side 804 and towards the second side 808 of the blade 352 , any air in front of the blade 352 during such movement is easily displaced.
- the blades 352 may be profiled such that the turbine assembly 208 including such blades 352 is rotated in one particular direction in the presence of a wind with a component that is tangential to the outer circumference of the turbine assembly 208 .
- the shape and/or contour of a blade 352 can be compound complex geometry and/or asymmetric geometry.
- the width W of the blade 352 can be different at different points along the length L of the blade 352 .
- an outer side edge or leading edge 812 of the blade 352 can be curved, to define the generally hemispherical shape of a turbine assembly 208 including the blade 352 .
- the blade 352 also includes an inner side edge or trailing edge 816 that, together with the outer side edge 812 , defines the width of the blade 352 . For example, and as shown in FIG.
- the side edges 812 and 816 can define a blade 352 with a width W that generally decreases from a base edge or end 820 of the blade 352 to the tapered or narrowed edge or end 824 of the blade 352 .
- the first surface 804 may curve from the base edge 820 to the tapered edge 824 .
- the curve may be generally inwardly from the base edge 820 to the tapered edge 824 .
- the blade 352 can also vary in the depth D of the cup or concave surface (or alternatively the height of the concave back surface 808 ).
- This depth D may vary with position along the length L of the blade 352 . For example, moving from the base edge 820 , the depth D can increase as the distance from the base edge 820 along the length L increases. After reaching a maximum point proximate the base edge 820 , the depth D may gradually decrease as the distance from the base edge 820 along the length L decreases, until a minimum depth D proximate the tapered edge 824 is reached.
- the blade 352 may be contoured so as to provide a lifting body or airfoil. Therefore, wind flowing across the blade 352 will produce lift, at least within some range of angles of attack. Accordingly, the blades 352 may comprise airfoils or lifting bodies. Moreover, lift generated by the blades 352 of a turbine assembly 208 will result in a force in a direction that tends to rotate the associated turbine assembly 208 . In addition, wind incident on the first surface 804 of a blade 352 is generally captured by the blade 352 , to promote a transfer of energy from that wind to, for example, a turbine assembly 208 that includes the blade 352 . Moreover, the blade 352 generally moves in a direction away from the wind. As a result, turbine assemblies 208 incorporating the blades 352 can comprise a combination of impulse turbine and reaction turbine operating characteristics.
- FIG. 9A is an illustration of a portion of a turbine assembly 208 in accordance with embodiments of the present invention.
- portions of a drive shaft 332 or 344 and of a blade support structure 356 are illustrated.
- the blade support structure 356 is shown as including a plurality of struts 604 .
- Each of the struts 604 can be interconnected to the drive shaft 332 or 344 via a hinge plate 906 and a compliance unit or structure 908 .
- Each hinge plate 906 is interconnected to the associated drive shaft 332 or 344 via a hinge 910 .
- the compliance unit 908 together with the hinge plate 906 , provide a mechanism by which an airfoil 352 can move relative to the interconnected drive shaft 332 or 344 when the force of the wind on the blade 352 is especially strong. Accordingly, high forces, for example from gusting winds or sudden increases in wind velocity, can be absorbed by the wind turbine system 104 in a controlled manner.
- FIG. 9B illustrates a turbine assembly 208 in plan view, with a blade 352 a that has been temporarily displaced by a gust of incident wind 404 .
- the radial spacing of the displaced blade 352 a with respect to the preceding blade 352 b has been increased, while the radial spacing between the displaced blade 352 a and a following blade 352 c has decreased.
- This change in radial spacing is a result of the struts 604 of the support structure 356 associated with the first blade 352 a transmitting a force to the compliance unit 908 that is greater than some threshold amount.
- Such a situation may occur, for example, where the incident wind 404 momentarily gusts.
- the compliance unit 908 can function as both a spring and a damper. More particularly, as depicted in FIG. 10 , the compliance unit 908 can include a housing 1002 and a shaft member 1004 with a first end 1008 that, in an assembled state, is interconnected to a strut 604 . The second end of the shaft 1004 comprises a plunger or piston 1012 . The piston 1012 travels within a fluid 1014 that fills the interior chamber 1016 of the compliance unit. The interior chamber 1016 can be separated from the ambient environment by first 1020 and second 1024 seals.
- An equalization plate 1028 having a plurality of holes 1032 formed therein divides the fluid filled chamber 1016 into first 1036 and second 1040 sub chambers, with the holes 1032 allowing for communication of the fluid 1014 between the first 1036 and second 1040 sub chambers.
- the equalization plate 1028 can travel along at least some of the length of the fluid filled chamber 1016 .
- a resilient member 1044 such as a spring or the like, can be provided within the second sub chamber 1040 .
- the resilient member 1044 biases the shaft 1004 towards a fully extended position.
- An inlet 1048 , and a relief fitting 1052 can be provided on the housing 1002 to allow for communication with the fluid filled chamber 1016 .
- various sensors 1056 can be provided, for example to monitor internal forces, operating temperatures, the position of the piston 1012 within the chamber 1016 , and/or other operating parameters.
- a force applied at the first end 1008 of the shaft 1004 for example from a gust of wind acting on a blade 352 supported at least in part by a strut 604 interconnected to the shaft 1004 , will tend to push the piston 1012 against the resilient member 1044 .
- the shaft will compress the resilient member 1044 , allowing the radial position of the associated blade 352 to change with respect to the associated shaft 332 or 344 .
- the piston 1032 and the equalization plate 1028 dampen movement of the shaft 1004 with respect to the housing 1002 . Accordingly, the rate at which the radial position of the blade 352 associated with the compliance unit 908 can change is restricted.
- the force on the blade 352 will lessen. Once the force transmitted by the blade 352 to the shaft 1004 is less than the countering force of the resilient member 1044 , the strut 1004 will be pushed back against the strut 604 , and the blade 352 will return to its normal radial position with respect to the associated drive shaft 332 or 344 . As can be appreciated by one of skill in the art after consideration of the present disclosure, the rate at which the shaft 1004 moves relative to the housing 1002 is limited by the damping effect provided by the flow of the fluid 1014 in the chamber 1016 through the holes 1032 in the equalization plate 1028 .
- compliance units 908 can be used to absorb sudden increases in the force imparted to a blade 352 by the incident wind.
- separate, instead of integrated, spring and damper units can be utilized.
- a compliance unit 908 can be arranged such that an associated spring operates in tension rather than compression.
- compliance can be provided by the support structure 356 , for example through the provision of flexible struts 604 .
- FIGS. 11A-11B illustrate shroud member 348 positions relative to the wind 404 , while the wind turbine system 104 is in a power generation mode, and while the wind 404 is incident on the wind turbine system 104 from a first direction. More particularly FIG. 11A is a view in elevation of a wind turbine system 104 in a power generation mode, with the wind traveling in a direction that is directly into the page. The configuration of the shrouds 348 illustrated in FIG. 11A is depicted in a top plan view in FIG. 11B . In this configuration, the wind turbine system 104 can draw a maximum amount of available energy from the incident wind 404 .
- one quadrant or about 90° of a first area 1104 a in a first hemisphere of the wind turbine system 104 is uncovered, thus exposing the first turbine assembly 208 a (see, e.g., FIG. 2 ) to the wind 404 .
- a second area 1104 b in a second hemisphere of the wind turbine system 104 is unshielded by the second shroud 348 b, exposing a portion of the second turbine assembly 208 b (see, e.g., FIG. 2 ) to the incident wind 404 .
- the turbine assemblies 208 by thus exposing the turbine assemblies 208 to the incident wind 404 , at least a first component of that incident wind 404 is tangential to the first turbine assembly 208 a, and at least a second component of the incident wind 404 is tangential to the second turbine assembly 208 b. Moreover, by exposing the turbine assemblies 208 to the wind at opposed quadrants of the wind turbine system 104 , the turbine assemblies 208 will tend to rotate in opposite directions. Moreover, the configuration exposes a first side 804 of the turbine assembly blades 352 to the incident wind 404 , while shielding the second side 808 of the blades 352 , promoting the efficient rotation of the turbine assemblies 208 .
- FIGS. 12A and 12B a wind turbine system 104 in a maximum power generation mode is again illustrated in elevation ( FIG. 12A ) and top plan ( FIG. 12B ) views.
- the direction of the incident wind 404 has shifted by about 15° as compared to the conditions depicted in FIGS. 11A and 11B .
- the rotational position of the shroud members 348 has changed.
- the shrouds 348 have been rotated about the system axis 324 , to maintain an exposure to the turbine assemblies 208 that maximizes the energy transferred from the incident wind 404 to the wind turbine system 104 .
- the absolute orientation of the shroud members 348 relative to the central axis 324 is shifted to track the change in wind 404 direction.
- FIGS. 13A and 13B depict an exemplary shroud member 348 configuration while the wind turbine system 104 is in a power generation mode, in the presence of a relatively strong incident wind 404 .
- the wind is traveling in a direction that is directly into the page.
- the areas 1104 a and 1104 b of exposure of the turbine assemblies 204 has been reduced. That is, more of the area of the wind turbine assemblies 204 is shielded by the shroud members 348 . Accordingly, the amount of wind 404 incident on the turbine assemblies 204 is reduced, thereby reducing the amount of energy transferred from the wind 404 by the wind turbine system 104 as compared to a configuration in which the exposed areas 1104 a and 1104 b are larger.
- the exposed area 1104 a and 1104 b can be further decreased if the velocity of the incident wind 404 increases. Similarly, in response to a decrease in the incident wind speed 404 , the exposed areas 1104 a and 1104 b can be increased, until the velocity of the incident wind 404 has decreased to below some threshold amount, at which point the maximum power configuration depicted in FIGS. 11A , 11 B, 12 A and 12 B is reached. Accordingly, the wind turbine system 104 can be selectively powered and depowered.
- the rotational positions of the shroud members 348 can be altered to track changes in the direction of the incident wind 404 .
- the areas 1104 a and 1104 b of exposed turbine assembly 208 remains depowered, the orientation of those areas has been shifted to track the change in the direction of the wind 404 .
- FIGS. 15A and 15B illustrate shroud member 348 positions relative to the wind 404 while the wind turbine system 104 is in an idle mode. More particularly, FIG. 15A is a view in elevation of a wind turbine system 104 in an idle mode, with the wind traveling in a direction that is directly into the page. The configuration of the shrouds 348 illustrated in FIG. 15A is depicted in top plan view in FIG. 15B . In this configuration, the turbine assemblies 208 are completely or substantially shielded from the incident wind 404 . This idle mode is generally entered when power generation is not desired or when the incident wind 404 velocity is too high for safe and reliable operation of the wind turbine system 104 .
- FIGS. 16A and 16B illustrate the shroud member 348 positions in the idle mode, but in the presence of a wind shift of about 75 ° as compared to the wind direction and the configuration illustrated in FIGS. 15A and 15B .
- the shroud assemblies 204 are positioned to place the respective shroud members 308 such that the turbine assemblies 208 remain shielded from the wind 404 . Therefore, it can be appreciated that, even in an idle mode, the position of the shroud members 348 about the system axis 324 can continue to be varied with changes in wind 404 direction.
- FIG. 17 is a flowchart depicting aspects of the operation of a wind turbine system 104 in accordance with embodiments of the present invention, and in particular operation while the wind turbine system 104 is in a power generation mode.
- the wind direction and velocity is determined (step 1704 ).
- the shroud members 348 are then positioned to expose the turbine assemblies 208 to the wind (step 1708 ). More particularly, a first shroud assembly 204 a shroud member 348 a can be positioned to uncover a first quadrant or other portion of a first turbine assembly 208 , such that the wind is incident on the first surface 804 of the blades 352 within that quadrant.
- a second shroud member 204 b can be positioned by rotating the second shroud member 348 b such that the wind is incident on a first surface 804 of some of the blades 352 of the second turbine assembly 208 b within a quadrant of the second turbine assembly. By thus exposing some of the blades 352 of the turbine assemblies 208 to the wind, those turbine assemblies 208 will begin to rotate relative to the central axis 324 of the wind turbine assembly 104 .
- the compliance units 908 protect the system 100 components from damage due to high winds, and in particular to sudden gusts or changes in wind speed, where the change in wind speed occurs too quickly to address through adjusting the shroud assemblies 204 to reduce the area of the turbine assemblies 208 exposed to the wind.
- a determination may be made as to whether the force of the wind causing the blade 352 to compress the associated compliance unit or units 908 has been removed. If the force has not yet been removed, the gust or increased wind continues to be absorbed by the compliance units 908 . If the force of the gust or sudden increase in wind has been removed, the blade 352 is returned to its normal position (step 1716 ).
- the blade 352 is returned to its normal position relative to the associated shaft 332 , 344 in a measured manner.
- the force of the resilient member 1044 returns the shaft 1004 to its normal, fully extended position, while the movement of the piston 1012 through the fluid 1016 , and the movement of the fluid 1016 through the holes 1032 of the equalization plate 1028 controls the rate at which the strut 1004 is returned to the extended position.
- the blade 352 will be returned to its normal position relative to the associated shaft 332 , 344 when the speed of the incident wind 404 has decreased by a sufficient amount, and/or when the blade has, through the rotation of the associated turbine assembly 208 , rotated out of the wind.
- the shroud assemblies 204 a and 204 b can be rotated in opposite directions about the system axis 324 to change the exposure of the turbine assemblies 208 to the wind. Moreover, the rotational position of the shroud assemblies 204 can be changed in response to a combination of a change in the direction and a change in the velocity of the wind.
- a wind turbine system 104 in accordance with embodiments of the present invention includes counter-rotating turbine assemblies 208 .
- a first turbine assembly 208 a includes a plurality of airfoils or blades that spin in a direction that is opposite the direction of spin of the second turbine assembly 208 b, thus substantially canceling out the inertia or twisting motion that would otherwise be induced by the force of turning the turbine assemblies 208 in only one direction.
- the geometry of the first turbine assembly 208 a blades 352 forces the incident wind 404 to not only turn the turbine assembly 204 a, but in addition to direct excess wind load upward into the second turbine assembly 208 b, thus acting similar to a two stage compressor and providing additional kinetic energy to move the second turbine assembly 208 b.
- the blades 352 of the first turbine assembly 208 a can be the mirror image of the blades 352 of the second turbine assembly 308 b and can comprise lifting bodies.
- the number of blades included in the first turbine assembly 208 a is generally different than the number of blades 352 included in the second turbine assembly 208 b. As examples, from 5 to 13 blades 352 can be included any one turbine assembly 208 .
- the blades 352 may be made from a variety of different materials such as but not limited to metals, composites, plastics, combinations thereof, and the like.
- the materials can include an ALUCOBONDTM composite material (an aluminum composite material that includes two sheets of aluminum thermo bonded to a polyethylene core), carbon composites, aluminum, galvanized metals, plastics or similar lightweight materials.
- the blades 352 may incorporate any of a number of different geometries and may comprise turbine blades, lifting bodies, airfoils, sails, and the like.
- the blades 352 can comprise a cambered surface that extends from about 10% to about 20% or higher from the side edges 812 and 816 of the blade 352 .
- the cambered surface can extend about 12%.
- an airfoil 352 can incorporate a curve when considered in a front elevation view.
- the shroud members 358 can comprise hemispherical aero shells.
- the shroud assemblies 204 incorporating the shroud members 358 can be formed from various materials. Suitable materials include ALCUBONDTM composite material, carbon composites, sheet metal, sheet screens, aluminum, plastics, or the like.
- Exemplary generators 212 include three phase induction generators at various outputs, depending on the size and intended use of the wind turbine system 104 .
- Exemplary power outputs include 60 KW, 120 KW, 200 KW, 500 KW and 700 KW production capacities.
- a generator 212 can provide output power to an inverter system, for distribution of electricity into an electrical power bus or transformers of the user and the public utility grid. Accordingly, 60 Hz alternating current power can be provided by the wind turbine system 104 , for use at the location of the wind turbine system 104 , and/or for distribution by the public utility grid.
- the turbine assemblies 208 have a radius from about 3 feet for a relatively small system to about 20 feet for a relatively large (e.g., 500 KW) system.
- the height of the overall wind turbine system 104 can range from about 14 feet for a small (e.g., 60 KW) system to about 50 feet for a large system.
- an individual blade 352 has a total area of greater than 54 square feet, as determined by Euler's formula as known one of ordinary skill in the art, for converting wind power into work power based on surface area presented to the wind stream.
- the operating revolutions per minute (RPM) of the turbine assemblies 208 can range from about 0 RPM to about 5,000 RPM and greater.
- a wind turbine system 104 in accordance with embodiments of the present invention can be controlled to maintain rotation of the turbine assemblies 208 between about 3,000 RPM to about 6,500 RPM.
Landscapes
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Development (AREA)
- Sustainable Energy (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Wind Motors (AREA)
Abstract
Wind turbine systems and methods are provided. The wind turbine system includes a plurality of coaxial, counter-rotating turbine assemblies. First and second shroud assemblies define a generally spherical volume containing the first and second turbine assemblies. The first and second shroud assemblies each include a shroud member that can selectively shield or expose portions of the respective turbine assemblies to the wind by changing the rotational position of the shroud members about the system axis. The turbine assemblies are interconnected to a generator for the production of electrical power.
Description
- This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/314,104, filed Mar. 15, 2010, the entire disclosure of which is hereby incorporated herein by reference. This application is related to U.S. Application Ser. No. ______, filed ______, entitled “WIND TURBINE CONTROL”, and identified as Attorney Docket No. 6228-2, the entire disclosure of which is hereby incorporated herein by reference.
- The present invention is directed to wind turbine systems and methods. More particularly, the present invention relates to wind turbine systems and methods that utilize counter-rotating turbine assemblies.
- Several decades of development have focused on harnessing the power of the wind to turn water and grist mills, and since the invention by Westinghouse in the late 1800's, to produce electrical power. Many types of designs have been proffered, however, they have been focused almost entirely on horizontal turbines with blades, sails or propellers to convert the kinetic energy of wind into a force to drive various types of electrical generators, including alternating current (AC), direct current (DC) and 3-phase current for storing and using power as the demand presents itself or to provide power directly into the public and private utility grids for distribution from substations to homes, offices, hotels, casinos, cities and municipalities, industrial and other energy dependent user applications.
- The past 20 years has seen a much greater emphasis on renewable energy sources as alternatives to fossil fuel power plants burning coal, natural gas, fuel oil or nuclear fuels to produce steam to power large scale electrical generators to reduce the impact of carbon compounds upon the Earth's atmosphere. These efforts have primarily been directed to large scale utility grids and the emphasis has been on large scale production systems (wind farms) greater than 1 megawatt that are geographically concentrated in remote locations where wind is available. It is now common to see systems greater than 4 megawatts in one tower. The systems developed can cost multi-million dollars each. The systems can be highly complex, enormous in size and scale and number in the tens of thousands in North America and world-wide. Towers of 200-400 feet in height are common on prairies and savannas, along our coastal regions, and even off-shore in shallow ocean waters. It was thought that these systems would have an enormous impact in offsetting the use of carbon based fuels and provide a cheap source of unlimited power.
- Unfortunately, this has not been the case and large utilities are now rethinking their use of these systems due to several inherent problems with the design and deployment of the systems. Among the problems impacting these systems are variations in wind speeds over the sweep of the propellers (60 ft-450 ft), ground turbulence that causes prop dithering and imbalance, and gusting winds that apply uneven forces and torqueing of the drive axles which have resulted in expensive and time consuming repairs of system mechanical drive trains and transmissions which cannot respond quickly to these changing dynamic loads. Other problems include overheating of the turbines resulting in transmission system and hydraulic system fires, wind loads that have caused complete system failure and total collapse of the towers, flickering light patterns disturbing cattle and other livestock, and complaints from people living near the turbines with regard to noise, bird kills, and flickering light patterns in their home windows. Recently complaints have been lodged by the Federal Aviation Administration and the United States AeroSpace Command regarding interference with air traffic control radar and guidance systems both on the ground and airborne caused by large scale wind farms.
- Additionally, significant losses in electrical energy are incurred due to long distance transmission from the wind farm sites to the utility substations which has resulted in low utilization of wind power and has reduced the effectiveness and reliability of the power generated. System shut down in gusty and turbulent wind conditions has resulted in “spiking” in the utility grid, creating inefficiency. The system loads can be unpredictable and unreliable. In many cases, wind energy is not used due to these problems and the utility industry is rethinking its investment and deployment strategy.
- On a smaller scale, wind turbine systems have been developed for generating power at or near the point of use. However, such systems have typically had only modest power generation capabilities, thereby limiting their application to the useful generation of power. For example, such systems have been utilized for low power applications, such as charging batteries and direct current (DC) applications. As a result, deployment of such systems has typically been limited to remote locations, where electrical power may otherwise be unavailable, as opposed to being deployed as an alternate energy source where grid power is otherwise available. Therefore, the use of wind generated electrical power at or near the point of use, on a scale at which the sale of electricity to an electric utility during times when the wind generated power is not entirely consumed at the location, has been limited.
- The present invention is directed to solving these and other problems and disadvantages of the prior art. In accordance with embodiments of the present invention, a wind turbine system having first and second turbine assemblies is provided. The first and second turbine assemblies are configured to rotate about a first axis, in opposite directions, in the presence of a suitable wind. In addition, first and second shroud assemblies are associated with the first and second wind turbine assemblies respectively. The first and second shroud assemblies extend around the outer circumference of the corresponding first and second turbine assemblies. In addition, the shroud assemblies include shroud members that extend around some portion of the outer circumference of the respective turbine assembly.
- In accordance with further embodiments of the present invention, the first turbine assembly is interconnected to a first drive shaft having an axis of rotation that is coincident with the first axis of the system. In addition, the second turbine assembly is interconnected to a second drive shaft that has an axis of rotation that also is coincident with the first axis of the system. Moreover, at least a portion of the second drive shaft can be received by and rotate within the first drive shaft. The first and second drive shafts are part of a drive train assembly that can operate to transfer wind energy from the turbine assemblies to a generator.
- A wind turbine system in accordance with embodiments of the present invention can include a base member to which the turbine assemblies and the shroud assemblies are interconnected, either directly or through other components. For example, the first shroud assembly can be interconnected to the base member, and the second shroud assembly can in turn be interconnected to the first shroud assembly. Moreover, the first shroud assembly can be selectively positioned by rotating the first shroud assembly about the first axis of the system and relative to the base member. In accordance with further embodiments of the present invention, the second shroud assembly can be selectively positioned by rotating the second shroud assembly about the first axis of the system relative to the base member and the first shroud assembly. In accordance with still further embodiments of the present invention, the first and second shroud assemblies can comprise a support structure that at least partially supports one or both of the turbine assemblies. In addition, the first drive shaft of the first wind turbine assembly can be rotatably interconnected to the base member. The second drive shaft of the second wind turbine assembly can also be rotatably interconnected to the base member. In addition, bearings can rotatably interconnect the first and second drive shafts. In accordance with still other embodiments, one or both of the first and second drive shafts can be interconnected to a support structure comprising one or both of the shroud assemblies.
- Methods in accordance with embodiments of the present invention include providing counter-rotating turbine assemblies. The turbine assemblies are selectively exposed to the wind through operation of shroud assemblies. More particularly, the shroud assemblies are rotated about a first axis of the system to expose a portion of a corresponding wind turbine assembly to the wind, while shielding another portion of that wind turbine assembly from the wind. The shroud assemblies can thus be used to control the exposure of the turbine assemblies to the wind so that the turbine assemblies are driven in a desired direction and to control the force of the wind on the turbine assemblies. In addition, the shroud assemblies can be positioned to entirely or substantially shield the turbine assemblies, for example where the generation of power is not desired, or to protect the wind turbine system from extremely strong winds.
- Additional features and advantages of embodiments of the present invention will become more readily apparent from the following description, particularly when taken together with the accompanying drawings.
-
FIG. 1 depicts a wind turbine system in accordance with embodiments of the present invention in an exemplary operating environment; -
FIG. 2 is a block diagram depicting components of a wind turbine system in accordance with embodiments of the present invention; -
FIG. 3 is a front view in elevation of a wind turbine system in accordance with embodiments of the present invention; -
FIG. 4 is a perspective view of a wind turbine system in accordance with embodiments of the present invention; -
FIG. 5 is a perspective view of wind turbine system support structure components in accordance with embodiments of the present invention; -
FIG. 6A is a top perspective view of a first turbine assembly in accordance with embodiments of the present invention; -
FIG. 6B is a top plan view of a first turbine assembly in accordance with embodiments of the present invention; -
FIG. 6C is a view in elevation of a first turbine assembly in accordance with embodiments of the present invention; -
FIG. 7A is a top perspective view of a second turbine assembly in accordance with embodiments of the present invention; -
FIG. 7B is a top plan view of a second turbine assembly in accordance with embodiments of the present invention; -
FIG. 7C is a view in elevation of a second turbine assembly in accordance with embodiments of the present invention; -
FIG. 8A is a front perspective view of a turbine assembly blade in accordance with embodiments of the present invention; -
FIG. 8B is a side elevation of a turbine assembly blade in accordance with embodiments of the present invention; -
FIG. 8C is a first end view of a turbine assembly blade in accordance with embodiments of the present invention; -
FIG. 8D is a second end view of a turbine assembly blade in accordance with embodiments of the present invention; -
FIG. 9A depicts a portion of a turbine assembly in accordance with embodiments of the present invention; -
FIG. 9B is a plan view of a turbine assembly with a blade that has been displaced in accordance with embodiments of the present invention; -
FIG. 10 is a cross-section of a compliance unit in accordance with embodiments of the present invention; -
FIG. 11A depicts a wind turbine system in accordance with embodiments of the present invention, and illustrates shroud member positions in an exemplary operating environment; -
FIG. 11B depicts the shroud member positions ofFIG. 11A in plan view; -
FIG. 12A depicts a wind turbine system in accordance with embodiments of the present invention, and illustrates shroud member positions in another operating environment; -
FIG. 12B depicts the shroud member positions ofFIG. 12A in plan view; -
FIG. 13A depicts a wind turbine system in accordance with embodiments of the present invention, and illustrates shroud member positions in another operating environment; -
FIG. 13B depicts the shroud member positions ofFIG. 13A in plan view; -
FIG. 14A depicts a wind turbine system in accordance with embodiments of the present invention, and illustrates shroud member positions in another operating environment; -
FIG. 14B depicts the shroud member positions ofFIG. 14A in plan view; -
FIG. 15A depicts a wind turbine system in accordance with embodiments of the present invention, and illustrates shroud member positions in another operating environment; -
FIG. 15B depicts the shroud member positions ofFIG. 15A in plan view; -
FIG. 16A depicts a wind turbine system in accordance with embodiments of the present invention, and illustrates shroud member positions in another operating environment; -
FIG. 16B depicts the shroud member positions ofFIG. 16A in plan view; and -
FIG. 17 is a flowchart depicting aspects of the operation of awind turbine system 104 in accordance with embodiments of the present invention, and in particular operation while thewind turbine system 104 is in a power generation mode. -
FIG. 1 depicts awind turbine system 104 in accordance with embodiments of the present invention, in an exemplary operating environment. In particular, thewind turbine system 104 is shown mounted to aplatform 108. In this example, theplatform 108 comprises a tall building, and thewind turbine system 104 is mounted to the roof of thatbuilding 108. However, awind turbine system 104 in accordance with embodiments of the present invention can be associated with any type ofplatform 108. Therefore, examples ofsuitable platforms 108 to which awind turbine system 104 as disclosed herein can be mounted include, in addition to tall buildings such as skyscrapers, mid-rise buildings, warehouses, big box retail stores, residences, towers, storage tanks, bridges or platforms. In addition, although depicted in an upright vertical orientation in the example ofFIG. 1 , awind turbine system 104 can be mounted in alternate orientations. For example, awind turbine system 104 can be mounted in a horizontal orientation, for instance to the side of aplatform 108 comprising a building or tower. As another example, awind turbine system 104 in accordance with embodiments of the present invention can be mounted in an upside down vertical orientation, for example to the underside of a bridge. -
FIG. 2 is a block diagram depicting components of awind turbine system 104 in accordance with embodiments of the present invention. In general, thewind turbine system 104 can include a number ofshroud assemblies 204. For instance, awind turbine system 104 can include afirst shroud assembly 204 a and asecond shroud assembly 204 b. In general, eachshroud assembly 204 is associated with and can at least partially define a volume containing aturbine assembly 208. Accordingly, awind turbine system 104 can include afirst turbine assembly 208 a and asecond turbine assembly 208 b. Theturbine assemblies 208 can be coupled to anelectrical generator 212 by adrive train assembly 216. Although referred to herein as agenerator 212, the component of thewind turbine system 104 used to generate electricity may comprise a motor operated as an electrical generator. As an example, and without limitation, thegenerator 212 may comprise a 60 Hz 3 phase permanent magnet generator. Moreover, thedrive train assembly 216 can include drive shafts that interconnect theturbine assemblies 208 to an input shaft of thegenerator 212 via a clutch. In accordance with embodiments of the present invention, thegenerator 212 can comprise any electrical generator. Thewind turbine system 104 can also include ashroud control system 220. Theshroud control system 220 can comprise motors, sensors, and controllers or processors for determining and controlling the position of theshroud assemblies 204. -
FIG. 3 depicts awind turbine system 104 in accordance with embodiments of the present invention in elevation. In this exemplary embodiment, thewind turbine system 104 is mounted to abase member 304 that is in turn mounted to theplatform 108. In this embodiment, thebase member 304 includes a bottom plate orfirst end surface 308 and a top plate orsecond end surface 312. Although the terms top and bottom are used throughout the specification for ease of description, it should be appreciated that thewind turbine system 104 can be oriented such that the bottom surface is above the top surface, or is at the same elevation or average elevation above the ground as the top surface, depending on the orientation of thewind turbine system 104. Accordingly, as used herein, a bottom surface, member or other element refers to an instance of the associated component or assembly that is more proximal to theplatform 108 or thebase member 304 than is a top component or assembly. The bottom plate orfirst end surface 308 can comprise a first circular end surface, while the top plate orsecond end surface 312 can comprise a second circular end surface. In this particular embodiment, thebase member 304 includes anintermediate section 316 having a diameter that is less than the diameter of the firstcircular end surface 308 and the secondcircular end surface 316. Accordingly, thebase member 304 can have a profile that is tapered in the center. - The
first shroud assembly 204 a is mounted to thebase member 304 via a first circular track orperipheral bearing assembly 320. The firstperipheral bearing assembly 320 allows thefirst shroud assembly 204 a to be rotated relative to thebase member 304 about a first orsystem axis 324. A firstcentral bearing assembly 328 can also be provided to rotatably interconnect thefirst shroud assembly 204 a to thebase member 304 and/or afirst drive shaft 332. Thesecond shroud assembly 204 b is interconnected to thefirst shroud assembly 204 a via a second circular track orequatorial bearing assembly 336. Theequatorial bearing assembly 336 allows thesecond shroud assembly 204 b to be rotated about thesystem axis 324 relative to thebase member 304, and relative to an independently of thefirst shroud assembly 204 a. A secondcentral bearing assembly 340 can also be provided to rotatably interconnect thesecond shroud assembly 204 b to asecond drive shaft 344. Sensors comprising position encoders can be associated with or incorporated into some or all of the bearingassemblies shroud control system 220 regarding the positions of theshroud assemblies 304 about thesystem axis 324. - Each of the
shroud assemblies 204 includes ashroud member 348. In particular, afirst shroud member 348 a associated with thefirst shroud assembly 204 a generally extends between the firstperipheral bearing assembly 320 and thehemispherical bearing assembly 336. In accordance with at least some embodiments, thefirst shroud member 348 a is mounted to thefirst shroud assembly 204 a via the firstperipheral bearing assembly 320 and theequatorial bearings assembly 336, and thus can be rotated relative to the system or central axis 124 and thefirst shroud assembly 204 a by moving theshroud member 348 a along the bearingassemblies first shroud member 348 a is generally hemispherical in that it extends for about one half the outer circumference of thefirst shroud assembly 204 a. Thesecond shroud assembly 348 b generally extends between thehemispherical bearing 336 to or near a top extent of thewind turbine system 104. In accordance with at least some embodiments, thesecond shroud member 348 b is mounted to thesecond shroud assembly 204 b via a second peripheral bearingassembly 322 and theequatorial bearing assembly 336, and can be rotated relative to the central axis 124 and thesecond shroud assembly 204 b by moving theshroud member 348 b along the bearingassembly second shroud assembly 204 b. In addition, theshroud assemblies 204 together define a shape that is generally spherical. - The
shroud assemblies 204 also generally describe a partially enclosed volume comprising a housing for theturbine assemblies 208. In particular, thefirst shroud assembly 204 a partially encloses thefirst turbine assembly 208 a. Similarly, thesecond shroud assembly 204 b partially encloses thesecond turbine assembly 208 b. The rotational locations about thesystem axis 324 that are enclosed by theshroud members 348 of theshroud assemblies 204 are controlled to provide a desired operational state of thewind turbine system 104, as described elsewhere herein. Moreover, positioning of theshroud assemblies 204 can be effected through the actuation of motors, such as stepper motors, associated with or incorporated into some or all of thebearings turbine assemblies 208 that each comprise a plurality of airfoils orblades 352 having afirst surface 804 and asecond surface 808. Moreover, theblades 352 of thefirst turbine assembly 208 a are oriented to rotate thatassembly 208 a in a first direction about thesystem axis 324, while theblades 352 of thesecond turbine assembly 208 b are oriented to rotate thatassembly 208 b in a second direction about thesystem axis 324. In accordance with embodiments of the present invention, thefirst turbine assembly 208 a may have a first number ofblades 352, and thesecond turbine assembly 208 b may have a second, different number ofblades 352. Accordingly, theturbine assemblies 208 are asynchronous in operation. Each of theblades 352 of thefirst turbine assembly 208 a can be interconnected to thefirst drive shaft 332 by ablade support structure 356. Similarly, each of theblades 352 of thesecond turbine assembly 208 b can be interconnected to thesecond drive shaft 344 by ablade support structure 356. Theblade support structure 356 can include one or more struts, although other configurations are possible. -
FIG. 4 is a perspective view of awind turbine system 104 in accordance with embodiments of the present invention. More particularly,FIG. 4 illustrates the relationship of awind turbine system 104 to a prevailingwind 404 and flow paths through thewind turbine system 104 under exemplary operating conditions. InFIG. 4 , theshroud assemblies 204 are shown positioned such that about a 90° section or arc of each of theturbine assemblies 208 is exposed to face thewind 404. Moreover, theshroud assemblies 204 are positioned so that the wind is incident on the first side orsurface 804 of theblades 352 of theturbine assemblies 208, and to allow thewind 404 to apply a generally tangential force on theturbine assemblies 208 such that theturbine assemblies 208 rotate in opposite directions about thesystem axis 324. Thus, in this example, the resulting exposure of theturbine assemblies 208 to theincident wind 404 causes thefirst turbine assembly 208 b to be rotated in a clockwise direction about thesystem axis 324, and causes thesecond turbine assembly 208 b to be rotated in a counter-clockwise direction, when thewind turbine system 104 is viewed from above. In addition, thewind turbine system 104 provides a stepper or dual compressor effect with respect to at least some of theincident wind 404. In particular, theblades 352 of thefirst turbine assembly 208 a generally direct at least some of the wind incident thereon upwards through thewind turbine system 104, to thesecond turbine assembly 204 b. Therefore, in addition to thewind 404 that is directly incident on theblades 352 of thesecond turbine assembly 208 b, at least some wind that was incident on theblades 352 of thefirst turbine assembly 204 a is available to also act on theblades 352 of thesecond turbine assembly 208 b. - As can be appreciated by one of skill in the art after consideration of the present disclosure, the counter-rotation of the first 208 a and second 208 b turbine assemblies results in a small or even zero torsional force on an associated
platform 108. In addition, thecounter-rotating turbine assemblies 208 can provide reduced vibration characteristics as compared to systems that do not employ counter rotating turbine assemblies or elements that are asynchronous due to having differing numbers of blades or airfoils. For example, thefirst turbine assembly 208 a may have a larger number of blades than thesecond turbine assembly 208 b. In addition, the flow paths of thewind 404 through theturbine assemblies 208 and the movement of theturbine assemblies 208 in a direction that is generally away from theincident wind 404 can provide a safer environment for birds and other wildlife. -
FIG. 5 is a perspective view of components of asupport structure 504 of a wind turbine system in accordance with embodiments of the present invention. In addition,FIG. 5 illustrates the generally spherical volume or truncated spherical volume defined by theshroud assemblies 204. Thesupport structure 504 can include thebase member 304, thefirst shroud assembly 204 a, and thesecond shroud assembly 204 b. Additional details of embodiments of theshroud assemblies 204 are also illustrated. In particular, it can be seen that eachshroud assembly 204 includes anequatorial support member 508. Moreover, theequatorial support member 508 a of thefirst shroud assembly 204 a is interconnected to theequatorial support member 508 b of thesecond shroud assembly 204 b by theequatorial bearing assembly 336. As discussed elsewhere herein, theequatorial bearing assembly 336 allows the rotational position of thesecond shroud assembly 204 b to be changed relative to thefirst shroud assembly 204 a and thebase member 304. In accordance with further embodiments of the present invention, eachshroud assembly 204 can include a number oflongitudinal support members 510. For example, eachshroud assembly 204 can include fourlongitudinal support members 510 spaced at 90° intervals. Moreover, eachshroud assembly 204 can includeradial members 514 that extend between theequatorial support member 508 and acenter ring 518 of the associatedshroud assembly 204. It can also be seen that, at least in some embodiments of the disclosed invention, the support for thesecond shroud assembly 204 b can be entirely or primarily provided by thefirst shroud assembly 204 a. - In addition to an
equatorial support member 508 andlongitudinal support members 510, eachshroud assembly 204 can include aweb structure 512. In general, theweb structure 512 provides support for acorresponding shroud assembly 204, at an end of thatshroud assembly 204 opposite theequatorial support member 508, and also provides support forlongitudinal support members 510 that extend between theweb structure 512 and theequatorial support member 508. Theweb structure 512 a associated with thefirst shroud assembly 204 a can also include or can be proximate to a portion of theperipheral bearing assembly 320 associated with thefirst shroud assembly 204 a, and/or thecentral bearing assembly 328. Theweb structure 512 b associated with thesecond shroud assembly 204 b can function to provide additional support for thesecond shroud member 348 b. In addition, thesecond web structure 512 b can include or be associated with a portion of the bearingassembly 340.FIG. 5 also illustrates anaccess panel 516 in thebase member 304. Theaccess panel 516 can be used to access thegenerator 212 and/or otherwind turbine system 104 components housed within thebase member 304. In accordance with other embodiments of the present invention, theshroud members 348 can be rotated around thecentral axis 324 relative to the associatedshroud assembly 204 support members and structures. For example, eachshroud member 348 can be mounted to the remainder of thewind turbine system 104 by theequatorial bearing assembly 336 and byend bearings 518 interconnected to theweb structure 512 of the associatedshroud assembly 204. -
FIGS. 6A-6C illustrate top perspective, top plan, and elevation views respectively of afirst turbine assembly 208 a in accordance with embodiments of the present invention. As previously noted, thefirst turbine assembly 208 a includes a plurality of airfoils orblades 352. In this example, eightblades 352 are shown. However, this is not a requirement, and the number ofblades 352 in a particular embodiment will depend on the design of theindividual airfoils 352 and other considerations. For instance, it is desirable to maintain a spacing betweenblades 352 that is sufficient to allow theindividual blades 352 to operate efficiently. In particular, ablade 352 can function as a lifting body through at least some portion of the rotation of theturbine assembly 208. For example, with an associatedshroud assembly 204 positioned so that theturbine assembly 208 can extract a maximum amount of energy from the wind, ablade 352 will act as a lifting body as it comes from behind theshroud member 348 and enters the air flow or wind, and for some additional degrees of rotation of theturbine assembly 208. Therefore, it is desirable to maintain a spacing betweenblades 352 that is large enough to allow eachblade 352 to generate lift without being negatively impacted by turbulence fromadjacent blades 352. Moreover, theblades 352 can be spaced such that as the angle of attack of ablade 352 increases and theblade 352 begins to spill wind, that spilled wind is directed towards and impacts adownwind blade 352. In addition, once theblade 352 has advanced to a point that theblade 352 is more normal to the wind, it is beneficial to maintain spacing between theblades 352 that is large enough to allow the wind to impact theblade 352 unimpeded or relatively unimpeded by thenext blade 352. As can be appreciated by one of skill in the art, in selecting the number ofblades 352 to include in aturbine assembly 208, the benefits of maintaining space betweenblades 352 is generally balanced against the additional force that can be extracted from wind of a given velocity by having a larger number ofblades 352 exposed to the wind at a particular moment in time. - Each
blade 352 in the illustrated example is interconnected to thefirst drive shaft 332 by asupport structure 356 comprising a plurality of support struts 604. From the views inFIGS. 6A-6C , it can be appreciated that theblades 352 are shaped to be effective to rotate the first drive shaft 335 when a portion of thewind turbine assembly 208 is exposed to an incident wind with a component that is generally tangential to an outer circumference of theturbine assembly 208 a. In particular, theblades 352 of the firstwind turbine assembly 208 a are configured to rotate the first drive shaft 335 in a clockwise direction, when the firstwind turbine assembly 204 a is viewed from above, and when exposed to such an incident wind. In addition, theblades 352 can be configured to direct at least some wind incident on theblades 352 in an end to end (e.g., a bottom to top) direction. Moreover, theouter edges 812 can be contoured so that the overall profile of the blade portion of thefirst turbine assembly 208 a is hemispherical or hemispherical-like. -
FIGS. 7A-7C illustrate asecond turbine assembly 208 b in accordance with embodiments of the present invention in top perspective, top plan and elevation views respectively. Similar to thefirst turbine assembly 208 a, thesecond turbine assembly 208 b includes a plurality of airfoils orblades 352. Theblades 352 of thesecond turbine assembly 208 b are interconnected to thesecond drive shaft 344 by asupport structure 356. In the illustrated example, thesupport structure 356 includes a plurality of support struts 604 associated with eachblade 352. In this embodiment, theblades 352 are configured to rotate thesecond drive shaft 344 in a counterclockwise direction when thesecond turbine assembly 208 b is viewed from above, in the presence of an incident wind having a component that is generally tangential to an outer circumference of theturbine assembly 208 a. In addition, it can be appreciated that theblades 352 are configured to impart a rotational force to thesecond drive shaft 344 in a counterclockwise direction in response to an updraft of wind (or a bottom to top flow generally parallel to the system axis 324), such as may be provided by afirst turbine assembly 208 a in awind turbine system 104 configured as illustrated in, for example,FIGS. 3 and 4 . It can also be appreciated that at least a portion of the wind incident on thesecond turbine assembly 208 b, either tangentially or as an updraft, can be exhausted in an upward direction (or in a direction generally parallel to the system axis 324). Theouter edges 812 of theblades 352 can be contoured so that the overall profile of the blade portion of thesecond turbine assembly 208 b is hemispherical or hemispherical-like. - In the example
first turbine assembly 208 a ofFIGS. 6A-6C , sevenblades 352 are shown, while in the examplesecond turbine assembly 208 b ofFIGS. 7A-7C , sixblades 352 are shown. The number ofblades 352 in theturbine assemblies 208 of a particular embodiment of awind turbine system 104 in accordance with the present invention will vary depending on the particular application and design considerations for example as described above in connection with thefirst turbine assembly 208 a. In accordance with at least some embodiments of the present invention, the first 208 a and second 208 b turbine assemblies each have a different number ofblades 352. In accordance with still further embodiments, thefirst turbine assembly 208 a has a larger number ofblades 352 than thesecond turbine assembly 208 b. By so configuring thewind turbine system 104, vibration and noise produced during operation of thewind turbine system 104 can be reduced as compared to embodiments in which the first 208 a and second 208 b turbine assemblies have the same number ofblades 352. -
FIGS. 8A-8D provide different views of ablade 352 of aturbine assembly 204 in accordance with embodiments of the present invention. In particular,FIG. 8A is a perspective view,FIG. 8B is a side elevation,FIG. 8C is a first plan view, andFIG. 8D is a second plan view of anexemplary blade 352 in accordance with embodiments of the present invention. Theblade 352 includes afirst surface 804 that is cupped or profiled to capture wind incident on thatsurface 804. In addition or as an alternative to trapping wind like a bucket, theblades 352 can comprise lifting bodies. Therefore, awind turbine system 104 can comprise both impulse turbine and reaction turbine operating principles. In operation, awind system 104 in accordance with embodiments of the present invention generally positions theshroud members 348 such that the wind is allowed to be incident on thefirst surface 804 of theturbine assembly 208blades 352. In addition, eachblade 352 has asecond surface 808 that is relatively streamlined such that, to the extent theblade 352 travels in a direction away from thefirst side 804 and towards thesecond side 808 of theblade 352, any air in front of theblade 352 during such movement is easily displaced. Accordingly, theblades 352 may be profiled such that theturbine assembly 208 includingsuch blades 352 is rotated in one particular direction in the presence of a wind with a component that is tangential to the outer circumference of theturbine assembly 208. - In addition, the shape and/or contour of a
blade 352 can be compound complex geometry and/or asymmetric geometry. For instance, the width W of theblade 352 can be different at different points along the length L of theblade 352. In addition, an outer side edge or leadingedge 812 of theblade 352 can be curved, to define the generally hemispherical shape of aturbine assembly 208 including theblade 352. Theblade 352 also includes an inner side edge or trailingedge 816 that, together with theouter side edge 812, defines the width of theblade 352. For example, and as shown inFIG. 8A , the side edges 812 and 816 can define ablade 352 with a width W that generally decreases from a base edge or end 820 of theblade 352 to the tapered or narrowed edge or end 824 of theblade 352. Moreover, thefirst surface 804 may curve from thebase edge 820 to thetapered edge 824. For example, the curve may be generally inwardly from thebase edge 820 to thetapered edge 824. - In addition to various curves and changes in dimension along the length L of the
blade 352 when considered in a front view (see generallyFIG. 8A ), theblade 352 can also vary in the depth D of the cup or concave surface (or alternatively the height of the concave back surface 808). This depth D may vary with position along the length L of theblade 352. For example, moving from thebase edge 820, the depth D can increase as the distance from thebase edge 820 along the length L increases. After reaching a maximum point proximate thebase edge 820, the depth D may gradually decrease as the distance from thebase edge 820 along the length L decreases, until a minimum depth D proximate thetapered edge 824 is reached. - After consideration of
FIGS. 8A-8D , it can be appreciated that theblade 352 may be contoured so as to provide a lifting body or airfoil. Therefore, wind flowing across theblade 352 will produce lift, at least within some range of angles of attack. Accordingly, theblades 352 may comprise airfoils or lifting bodies. Moreover, lift generated by theblades 352 of aturbine assembly 208 will result in a force in a direction that tends to rotate the associatedturbine assembly 208. In addition, wind incident on thefirst surface 804 of ablade 352 is generally captured by theblade 352, to promote a transfer of energy from that wind to, for example, aturbine assembly 208 that includes theblade 352. Moreover, theblade 352 generally moves in a direction away from the wind. As a result,turbine assemblies 208 incorporating theblades 352 can comprise a combination of impulse turbine and reaction turbine operating characteristics. -
FIG. 9A is an illustration of a portion of aturbine assembly 208 in accordance with embodiments of the present invention. In particular, portions of adrive shaft blade support structure 356 are illustrated. Theblade support structure 356 is shown as including a plurality ofstruts 604. Each of thestruts 604 can be interconnected to thedrive shaft hinge plate 906 and a compliance unit orstructure 908. Eachhinge plate 906 is interconnected to the associateddrive shaft hinge 910. Thecompliance unit 908, together with thehinge plate 906, provide a mechanism by which anairfoil 352 can move relative to theinterconnected drive shaft blade 352 is especially strong. Accordingly, high forces, for example from gusting winds or sudden increases in wind velocity, can be absorbed by thewind turbine system 104 in a controlled manner. -
FIG. 9B illustrates aturbine assembly 208 in plan view, with ablade 352 a that has been temporarily displaced by a gust ofincident wind 404. In particular, the radial spacing of the displacedblade 352 a with respect to thepreceding blade 352 b has been increased, while the radial spacing between the displacedblade 352 a and afollowing blade 352 c has decreased. This change in radial spacing is a result of thestruts 604 of thesupport structure 356 associated with thefirst blade 352 a transmitting a force to thecompliance unit 908 that is greater than some threshold amount. Such a situation may occur, for example, where theincident wind 404 momentarily gusts. Accordingly, excess wind or a sudden increase in force imparted to ablade 352 can be absorbed. In particular, theblade 352 is allowed to open, dumping wind while absorbing force by moving against thecompliance unit 908. With reference again toFIG. 9A , it can be appreciated that, as the radial position of theblade 352 with respect to thedrive shaft compliance unit 908 is compressed, and thehinge plate 906 pivots about thehinge 910 with respect to eachstrut 604 included in thesupport structure 356. - In accordance with further embodiments of the present invention, the
compliance unit 908 can function as both a spring and a damper. More particularly, as depicted inFIG. 10 , thecompliance unit 908 can include ahousing 1002 and ashaft member 1004 with afirst end 1008 that, in an assembled state, is interconnected to astrut 604. The second end of theshaft 1004 comprises a plunger orpiston 1012. Thepiston 1012 travels within a fluid 1014 that fills theinterior chamber 1016 of the compliance unit. Theinterior chamber 1016 can be separated from the ambient environment by first 1020 and second 1024 seals. Anequalization plate 1028 having a plurality ofholes 1032 formed therein divides the fluid filledchamber 1016 into first 1036 and second 1040 sub chambers, with theholes 1032 allowing for communication of the fluid 1014 between the first 1036 and second 1040 sub chambers. Theequalization plate 1028 can travel along at least some of the length of the fluid filledchamber 1016. In addition, aresilient member 1044, such as a spring or the like, can be provided within thesecond sub chamber 1040. Theresilient member 1044 biases theshaft 1004 towards a fully extended position. Aninlet 1048, and arelief fitting 1052 can be provided on thehousing 1002 to allow for communication with the fluid filledchamber 1016. Moreover,various sensors 1056 can be provided, for example to monitor internal forces, operating temperatures, the position of thepiston 1012 within thechamber 1016, and/or other operating parameters. - In operation, a force applied at the
first end 1008 of theshaft 1004, for example from a gust of wind acting on ablade 352 supported at least in part by astrut 604 interconnected to theshaft 1004, will tend to push thepiston 1012 against theresilient member 1044. When the force applied through theshaft 1004 to theresilient member 1044 is great enough, the shaft will compress theresilient member 1044, allowing the radial position of the associatedblade 352 to change with respect to the associatedshaft piston 1032 and theequalization plate 1028 dampen movement of theshaft 1004 with respect to thehousing 1002. Accordingly, the rate at which the radial position of theblade 352 associated with thecompliance unit 908 can change is restricted. As theblade 352 continues its rotation away from the incident wind 404 (seeFIG. 9B ), the force on theblade 352 will lessen. Once the force transmitted by theblade 352 to theshaft 1004 is less than the countering force of theresilient member 1044, thestrut 1004 will be pushed back against thestrut 604, and theblade 352 will return to its normal radial position with respect to the associateddrive shaft shaft 1004 moves relative to thehousing 1002 is limited by the damping effect provided by the flow of the fluid 1014 in thechamber 1016 through theholes 1032 in theequalization plate 1028. As can be appreciated by one of skill in the art after consideration of the present disclosure, different configurations ofcompliance units 908 can be used to absorb sudden increases in the force imparted to ablade 352 by the incident wind. For example, separate, instead of integrated, spring and damper units can be utilized. As a further example, acompliance unit 908 can be arranged such that an associated spring operates in tension rather than compression. In accordance with still other embodiments, compliance can be provided by thesupport structure 356, for example through the provision offlexible struts 604. -
FIGS. 11A-11B illustrateshroud member 348 positions relative to thewind 404, while thewind turbine system 104 is in a power generation mode, and while thewind 404 is incident on thewind turbine system 104 from a first direction. More particularlyFIG. 11A is a view in elevation of awind turbine system 104 in a power generation mode, with the wind traveling in a direction that is directly into the page. The configuration of theshrouds 348 illustrated inFIG. 11A is depicted in a top plan view inFIG. 11B . In this configuration, thewind turbine system 104 can draw a maximum amount of available energy from theincident wind 404. In particular, one quadrant or about 90° of afirst area 1104 a in a first hemisphere of thewind turbine system 104 is uncovered, thus exposing thefirst turbine assembly 208 a (see, e.g.,FIG. 2 ) to thewind 404. Similarly, asecond area 1104 b in a second hemisphere of thewind turbine system 104 is unshielded by thesecond shroud 348 b, exposing a portion of thesecond turbine assembly 208 b (see, e.g.,FIG. 2 ) to theincident wind 404. As can be appreciated by one of skill in the art after consideration of the disclosure provided herein, by thus exposing theturbine assemblies 208 to theincident wind 404, at least a first component of thatincident wind 404 is tangential to thefirst turbine assembly 208 a, and at least a second component of theincident wind 404 is tangential to thesecond turbine assembly 208 b. Moreover, by exposing theturbine assemblies 208 to the wind at opposed quadrants of thewind turbine system 104, theturbine assemblies 208 will tend to rotate in opposite directions. Moreover, the configuration exposes afirst side 804 of theturbine assembly blades 352 to theincident wind 404, while shielding thesecond side 808 of theblades 352, promoting the efficient rotation of theturbine assemblies 208. - In
FIGS. 12A and 12B , awind turbine system 104 in a maximum power generation mode is again illustrated in elevation (FIG. 12A ) and top plan (FIG. 12B ) views. However, in these views, the direction of theincident wind 404 has shifted by about 15° as compared to the conditions depicted inFIGS. 11A and 11B . In response to this shift in the direction of thewind 404, the rotational position of theshroud members 348 has changed. In particular, theshrouds 348 have been rotated about thesystem axis 324, to maintain an exposure to theturbine assemblies 208 that maximizes the energy transferred from theincident wind 404 to thewind turbine system 104. Therefore, while the same or about thesame area areas FIGS. 11A and 11B when considered from a view taken along the wind direction), the absolute orientation of theshroud members 348 relative to thecentral axis 324 is shifted to track the change inwind 404 direction. -
FIGS. 13A and 13B depict anexemplary shroud member 348 configuration while thewind turbine system 104 is in a power generation mode, in the presence of a relativelystrong incident wind 404. With respect toFIG. 13A , the wind is traveling in a direction that is directly into the page. In this configuration, theareas turbine assemblies 204 has been reduced. That is, more of the area of thewind turbine assemblies 204 is shielded by theshroud members 348. Accordingly, the amount ofwind 404 incident on theturbine assemblies 204 is reduced, thereby reducing the amount of energy transferred from thewind 404 by thewind turbine system 104 as compared to a configuration in which the exposedareas area incident wind 404 increases. Similarly, in response to a decrease in theincident wind speed 404, the exposedareas incident wind 404 has decreased to below some threshold amount, at which point the maximum power configuration depicted inFIGS. 11A , 11B, 12A and 12B is reached. Accordingly, thewind turbine system 104 can be selectively powered and depowered. - While operating in the power generation mode in the presence of strong incident wind, in addition to reducing the exposed
areas shroud members 348 can be altered to track changes in the direction of theincident wind 404. An example of a change in the position of theshroud members 348 due to a change in direction of astrong incident wind 404, as compared to the direction of the strong incident wind depicted inFIGS. 13A and 13B , is depicted inFIGS. 14A and 14B . In particular, while theareas turbine assembly 208 remains depowered, the orientation of those areas has been shifted to track the change in the direction of thewind 404. -
FIGS. 15A and 15B illustrateshroud member 348 positions relative to thewind 404 while thewind turbine system 104 is in an idle mode. More particularly,FIG. 15A is a view in elevation of awind turbine system 104 in an idle mode, with the wind traveling in a direction that is directly into the page. The configuration of theshrouds 348 illustrated inFIG. 15A is depicted in top plan view inFIG. 15B . In this configuration, theturbine assemblies 208 are completely or substantially shielded from theincident wind 404. This idle mode is generally entered when power generation is not desired or when theincident wind 404 velocity is too high for safe and reliable operation of thewind turbine system 104. -
FIGS. 16A and 16B illustrate theshroud member 348 positions in the idle mode, but in the presence of a wind shift of about 75° as compared to the wind direction and the configuration illustrated inFIGS. 15A and 15B . In particular, in order to track the shift inwind 404 direction, theshroud assemblies 204 are positioned to place therespective shroud members 308 such that theturbine assemblies 208 remain shielded from thewind 404. Therefore, it can be appreciated that, even in an idle mode, the position of theshroud members 348 about thesystem axis 324 can continue to be varied with changes inwind 404 direction. -
FIG. 17 is a flowchart depicting aspects of the operation of awind turbine system 104 in accordance with embodiments of the present invention, and in particular operation while thewind turbine system 104 is in a power generation mode. Initially, after entering the power generation mode, the wind direction and velocity is determined (step 1704). Theshroud members 348 are then positioned to expose theturbine assemblies 208 to the wind (step 1708). More particularly, afirst shroud assembly 204 ashroud member 348 a can be positioned to uncover a first quadrant or other portion of afirst turbine assembly 208, such that the wind is incident on thefirst surface 804 of theblades 352 within that quadrant. Similarly, asecond shroud member 204 b can be positioned by rotating thesecond shroud member 348 b such that the wind is incident on afirst surface 804 of some of theblades 352 of thesecond turbine assembly 208 b within a quadrant of the second turbine assembly. By thus exposing some of theblades 352 of theturbine assemblies 208 to the wind, thoseturbine assemblies 208 will begin to rotate relative to thecentral axis 324 of thewind turbine assembly 104. - A determination may then be made as to whether the
incident wind 404 has gusted or otherwise suddenly increased (step 1710). If thewind 404 has suddenly increased, the energy imparted to ablade 352 that is receiving a force from thewind 404 in excess of a predetermined amount is absorbed by thecompliance units 908 included in the affected blade's 352 support structure 356 (step 1712). In particular, when the force on theblade 352 is sufficiently high, e.g., greater than a predetermined amount, theshaft 1004 of thecompliance unit 908 is compressed against theresident member 1044. As can be appreciated by one of skill in the art after consideration of the present disclosure, the ability to absorb forces on theturbine assembly blades 352 caused by high winds protects the wind turbine system 100 components. In addition, thecompliance units 908 protect the system 100 components from damage due to high winds, and in particular to sudden gusts or changes in wind speed, where the change in wind speed occurs too quickly to address through adjusting theshroud assemblies 204 to reduce the area of theturbine assemblies 208 exposed to the wind. Atstep 1714, a determination may be made as to whether the force of the wind causing theblade 352 to compress the associated compliance unit orunits 908 has been removed. If the force has not yet been removed, the gust or increased wind continues to be absorbed by thecompliance units 908. If the force of the gust or sudden increase in wind has been removed, theblade 352 is returned to its normal position (step 1716). In accordance with embodiments of the present invention, theblade 352 is returned to its normal position relative to the associatedshaft resilient member 1044 returns theshaft 1004 to its normal, fully extended position, while the movement of thepiston 1012 through the fluid 1016, and the movement of the fluid 1016 through theholes 1032 of theequalization plate 1028 controls the rate at which thestrut 1004 is returned to the extended position. As can be appreciated by one of skill in the art after consideration of the present disclosure, theblade 352 will be returned to its normal position relative to the associatedshaft incident wind 404 has decreased by a sufficient amount, and/or when the blade has, through the rotation of the associatedturbine assembly 208, rotated out of the wind. - At
step 1720, a determination may be made as to whether an actionable change in either the wind velocity or the wind direction has been observed. If an actionable change in wind velocity or direction has been observed, the position of theshroud members 348 can be changed (step 1724). For instance, if the direction of the wind has changed by at least some minimum number of degrees, theshroud assemblies 204 can be rotated about thesystem axis 324 in the same direction such that the exposure of the first 208 a and second 208 b turbine assemblies to the wind remains equal or substantially equal. As an example, and without limitation, an actionable change can occur when the wind direction is more than 5° to either side of being equally incident on the shroud members 358. In response to a change in wind velocity, theshroud assemblies system axis 324 to change the exposure of theturbine assemblies 208 to the wind. Moreover, the rotational position of theshroud assemblies 204 can be changed in response to a combination of a change in the direction and a change in the velocity of the wind. - At
step 1728, a determination may be made as to whether the power generation mode is to be continued. If power generation is to be continued, the process may return tostep 1710. If the power generation mode is to be discontinued, the process may end. - As disclosed herein, a
wind turbine system 104 in accordance with embodiments of the present invention includescounter-rotating turbine assemblies 208. In at least some embodiments, afirst turbine assembly 208 a includes a plurality of airfoils or blades that spin in a direction that is opposite the direction of spin of thesecond turbine assembly 208 b, thus substantially canceling out the inertia or twisting motion that would otherwise be induced by the force of turning theturbine assemblies 208 in only one direction. In addition, the geometry of thefirst turbine assembly 208 ablades 352 forces theincident wind 404 to not only turn theturbine assembly 204 a, but in addition to direct excess wind load upward into thesecond turbine assembly 208 b, thus acting similar to a two stage compressor and providing additional kinetic energy to move thesecond turbine assembly 208 b. In addition, theblades 352 of thefirst turbine assembly 208 a can be the mirror image of theblades 352 of the second turbine assembly 308 b and can comprise lifting bodies. The number of blades included in thefirst turbine assembly 208 a is generally different than the number ofblades 352 included in thesecond turbine assembly 208 b. As examples, from 5 to 13blades 352 can be included any oneturbine assembly 208. - The
blades 352 may be made from a variety of different materials such as but not limited to metals, composites, plastics, combinations thereof, and the like. For example, the materials can include an ALUCOBOND™ composite material (an aluminum composite material that includes two sheets of aluminum thermo bonded to a polyethylene core), carbon composites, aluminum, galvanized metals, plastics or similar lightweight materials. Theblades 352 may incorporate any of a number of different geometries and may comprise turbine blades, lifting bodies, airfoils, sails, and the like. In an exemplary configuration, theblades 352 can comprise a cambered surface that extends from about 10% to about 20% or higher from the side edges 812 and 816 of theblade 352. As a particular example, the cambered surface can extend about 12%. In addition, anairfoil 352 can incorporate a curve when considered in a front elevation view. - The shroud members 358 can comprise hemispherical aero shells. The
shroud assemblies 204 incorporating the shroud members 358 can be formed from various materials. Suitable materials include ALCUBOND™ composite material, carbon composites, sheet metal, sheet screens, aluminum, plastics, or the like. -
Exemplary generators 212 include three phase induction generators at various outputs, depending on the size and intended use of thewind turbine system 104. Exemplary power outputs include 60 KW, 120 KW, 200 KW, 500 KW and 700 KW production capacities. As can be appreciated by one of skill in the art after consideration of the present disclosure, agenerator 212 can provide output power to an inverter system, for distribution of electricity into an electrical power bus or transformers of the user and the public utility grid. Accordingly, 60 Hz alternating current power can be provided by thewind turbine system 104, for use at the location of thewind turbine system 104, and/or for distribution by the public utility grid. - In an exemplary configuration, the
turbine assemblies 208 have a radius from about 3 feet for a relatively small system to about 20 feet for a relatively large (e.g., 500 KW) system. The height of the overallwind turbine system 104 can range from about 14 feet for a small (e.g., 60 KW) system to about 50 feet for a large system. In one exemplary embodiment, anindividual blade 352 has a total area of greater than 54 square feet, as determined by Euler's formula as known one of ordinary skill in the art, for converting wind power into work power based on surface area presented to the wind stream. - The operating revolutions per minute (RPM) of the
turbine assemblies 208 can range from about 0 RPM to about 5,000 RPM and greater. For example, awind turbine system 104 in accordance with embodiments of the present invention can be controlled to maintain rotation of theturbine assemblies 208 between about 3,000 RPM to about 6,500 RPM. - The foregoing discussion of the invention has been presented for purposes of illustration and description. Further, the description is not intended to limit the invention to the form disclosed herein. Consequently, variations and modifications commensurate with the above teachings, within the skill or knowledge of the relevant art, are within the scope of the present invention. The embodiments described hereinabove are further intended to explain the best mode presently known of practicing the invention and to enable others skilled in the art to utilize the invention in such or in other embodiments and with various modifications required by the particular application or use of the invention. It is intended that the appended claims be construed to include alternative embodiments to the extent permitted by the prior art.
Claims (20)
1. A wind turbine system, comprising:
a base member;
a first turbine assembly, wherein the first turbine assembly is interconnected to the base member, and wherein the first turbine assembly is rotatable about a first axis;
a second turbine assembly, wherein the second turbine assembly is interconnected to the base member, and wherein the second turbine assembly is rotatable about the first axis;
a first shroud assembly, including:
a first shroud member, wherein the first shroud assembly is interconnected to the base member, and wherein the first shroud member extends at least partially around an outer circumference of the first turbine assembly;
a second shroud assembly, including:
a second shroud member, wherein the second shroud assembly is interconnected to the base member, and wherein the second shroud member extends at least partially around an outer circumference of the first turbine assembly.
2. The system of claim 1 , wherein the first turbine assembly includes a first plurality of blades, wherein the second turbine assembly includes a second plurality of blades, and wherein the number of blades included in the first plurality of blades is different than the number of blades included in the second plurality of blades.
3. The system of claim 2 , further comprising:
a plurality of blade support structures, wherein each blade in the first plurality of blades and each blade in the second plurality of blades is associated with a support structure, each support structure including a compliance member, wherein in response to a force greater than a first predetermined amount, a radial position of a blade relative to an associated drive shaft is changed.
4. The system of claim 1 , wherein in a first operational mode the first turbine assembly is configured to spin in a first direction around the first axis, and wherein in the first operational mode the second turbine is configured to spin in a second direction around the first axis.
5. The system of claim 1 , wherein the first shroud member extends around at least one half of the outer circumference of the first turbine assembly, and wherein the second shroud member extends around at least one half of the outer circumference of the second turbine assembly.
6. The system of claim 1 , wherein the first and second shroud assemblies are rotatable about the first axis.
7. The system of claim 1 , further comprising:
a generator, wherein the generator includes an input shaft;
a drive train assembly interconnected to the input shaft of the generator, the drive train assembly including:
a first drive shaft, wherein the first turbine assembly is interconnected to the first drive shaft;
a second drive shaft, wherein the second turbine assembly is interconnected to the second drive shaft.
8. The system of claim 1 , wherein the base member includes:
a first circular end surface having a first diameter;
a second circular end surface having a second diameter;
a medial section having a third diameter, wherein the third diameter is smaller than the first diameter, and wherein the third diameter is smaller than the second diameter.
9. The system of claim 1 , wherein the first shroud assembly defines a first exposed area of the first turbine assembly.
10. The system of claim 9 , wherein the second shroud assembly defines a second exposed area of the second turbine assembly.
11. A method for providing a wind turbine system, comprising:
interconnecting a first turbine assembly to a base member, wherein the first turbine assembly is located about a first axis;
interconnecting a second turbine assembly to the base member, wherein the second turbine assembly is located about the first axis;
selectively shielding a first portion of the first turbine assembly from a wind using a first shroud assembly, wherein the first shroud assembly partially shields at least a portion of the first turbine assembly, and wherein the first shroud assembly is located about the first axis;
selectively shielding a first portion of the second turbine assembly from the wind using a second shroud assembly, wherein the first shroud assembly partially shields at least a portion of the second turbine assembly, and wherein the second shroud assembly is located about the first axis.
12. The method of claim 11 , further comprising:
in a first operational mode:
selectively exposing a second portion of the first turbine assembly to the wind, wherein the first turbine assembly is rotated about the first axis in a first direction;
selectively exposing a second portion of the second turbine assembly to the wind, wherein the second turbine assembly is rotated about the first axis in a second direction.
13. The method of claim 12 , further comprising:
detecting a shift in the wind of at least a first predetermined amount;
changing a rotational position of the first shroud assembly about the first axis and changing a rotational position of the second shroud assembly about the second axis.
14. The method of claim 12 , further comprising:
driving a generator using the first second and turbine assemblies.
15. The method of claim 12 , further comprising:
experiencing a sudden increase in a force imparted to a blade of at least one of the first and second turbine assemblies;
in response to the force being at least a first predetermined amount, changing a radial position of the blade relative to other blades of the at least one of the first and second turbine assemblies.
16. The method of claim 15 , further comprising:
in response to the force from the wind on the blade dropping below the first predetermined amount, returning the blade to a normal position relative to the other blades in the at least one of the first and second turbine assemblies.
17. A wind turbine system, comprising:
a base member;
a generator interconnected to the base member;
a first shroud assembly interconnected to the base member, the first shroud assembly including a first shroud member, wherein the first shroud member can be rotated about a system axis to change a location of the first shroud member about the system axis;
a second shroud assembly interconnected to the second shroud assembly, the second shroud assembly including a second shroud member, wherein the second shroud member can be rotated about the system axis to change a location of the second shroud member about the system axis, and wherein the first and second shroud assemblies define a volume;
a first turbine assembly interconnected to the generator, wherein the first turbine assembly is located in the volume defined by the first and second shroud assemblies, and wherein the first shroud member partially encloses the volume in at least a first area adjacent the first turbine assembly;
a second turbine assembly interconnected to the generator, wherein the second turbine assembly is located in the volume defined by the first and second shroud assemblies, and wherein the second shroud member partially encloses the volume in at least a second area adjacent the second turbine assembly.
18. The system of claim 17 , further comprising:
a controller, including a processor and at least a first sensor, wherein the controller is operable to control the location of the first and second shield members about the system axis in response to information from the at least a first sensor.
19. The system of claim 17 , further comprising:
a plurality of blades,
wherein the first turbine assembly includes a first plurality of blades;
wherein the second turbine assembly includes a second plurality of blades.
20. The system of claim 17 , wherein at least a first flow path is defined by the first shroud, wherein the first flow path intersects the first turbine assembly, and wherein the first flow path also intersects the second turbine assembly.
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13/039,951 US20110158787A1 (en) | 2010-03-15 | 2011-03-03 | Wind turbine |
US13/635,612 US8894348B2 (en) | 2010-03-15 | 2011-03-11 | Wind turbine |
PCT/US2011/028161 WO2011115845A1 (en) | 2010-03-15 | 2011-03-11 | Wind turbine |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US31410410P | 2010-03-15 | 2010-03-15 | |
US13/039,951 US20110158787A1 (en) | 2010-03-15 | 2011-03-03 | Wind turbine |
Related Child Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/635,612 Continuation US8894348B2 (en) | 2010-03-15 | 2011-03-11 | Wind turbine |
Publications (1)
Publication Number | Publication Date |
---|---|
US20110158787A1 true US20110158787A1 (en) | 2011-06-30 |
Family
ID=44186537
Family Applications (3)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/039,951 Abandoned US20110158787A1 (en) | 2010-03-15 | 2011-03-03 | Wind turbine |
US13/039,954 Abandoned US20110156392A1 (en) | 2010-03-15 | 2011-03-03 | Wind turbine control |
US13/635,612 Expired - Fee Related US8894348B2 (en) | 2010-03-15 | 2011-03-11 | Wind turbine |
Family Applications After (2)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/039,954 Abandoned US20110156392A1 (en) | 2010-03-15 | 2011-03-03 | Wind turbine control |
US13/635,612 Expired - Fee Related US8894348B2 (en) | 2010-03-15 | 2011-03-11 | Wind turbine |
Country Status (2)
Country | Link |
---|---|
US (3) | US20110158787A1 (en) |
WO (2) | WO2011115845A1 (en) |
Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20110049894A1 (en) * | 2006-10-06 | 2011-03-03 | Green William M | Electricity Generating Assembly |
US20120061965A1 (en) * | 2011-11-21 | 2012-03-15 | Khedekar Samit A | Vertical axis wind turbine with electronically controlled assisted start mechanism and controlled airflow |
US20120074701A1 (en) * | 2010-09-24 | 2012-03-29 | Frank Hernandez | Ridge cap wind generation system |
US8894348B2 (en) | 2010-03-15 | 2014-11-25 | II Andrew Carlton Thacker | Wind turbine |
US20150098795A1 (en) * | 2013-10-08 | 2015-04-09 | Aurelio Izquierdo Gonzalez | Vertical-Axis Wind Turbine With Protective Screen |
US20160153308A1 (en) * | 2013-07-31 | 2016-06-02 | Claudio MUNERATO | Auxiliary generator of electrical energy |
DE102019100208A1 (en) * | 2019-01-07 | 2020-07-09 | Dirk Petersen | Vertical wind turbine |
US11085303B1 (en) * | 2020-06-16 | 2021-08-10 | General Electric Company | Pressurized damping fluid injection for damping turbine blade vibration |
Families Citing this family (17)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US10851758B2 (en) * | 2009-10-02 | 2020-12-01 | Jose Ramon Santana | Hydrokinetic transport wheel mount |
ITRM20110516A1 (en) * | 2011-09-30 | 2013-03-31 | Enel Green Power Spa | HORIZONTAL AXIS WIND GENERATOR WITH SECONDARY WIND ROTOR |
US9127646B2 (en) * | 2012-03-09 | 2015-09-08 | V3 Technologies, Llc | Toroidal augmented wind power generation system using a modified and integrated vertical axis wind turbine rotor and generator assembly |
KR101251885B1 (en) | 2012-03-23 | 2013-04-08 | 진동진 | Apparatus for measuring direction and velocity of wind using ultrasonic by self power generating with analog anemoscope and analog anemometer |
US20160084222A1 (en) * | 2012-08-20 | 2016-03-24 | Chuy-Nan Chio | Omni-directional wind power harnessing device |
TWI522529B (en) * | 2013-06-28 | 2016-02-21 | 國立臺灣海洋大學 | Vertical axis wind turbine |
US10890161B1 (en) * | 2014-08-20 | 2021-01-12 | Bhaskar R Vemuri | Embedded electrical energy platform |
US20160230742A1 (en) * | 2015-02-05 | 2016-08-11 | Vijay Rao | Wind Turbine |
US20180030956A1 (en) * | 2015-02-05 | 2018-02-01 | Vijay Rao | Fluid Turbine with Control System |
US9699967B2 (en) * | 2015-09-25 | 2017-07-11 | Deere & Company | Crosswind compensation for residue processing |
PL228025B1 (en) * | 2015-11-24 | 2018-02-28 | Ireneusz Piskorz | A unit utilizing solar and wind energy |
US20170234302A1 (en) * | 2015-11-25 | 2017-08-17 | Hattar Tanin LLC | Innovative wind turbine construction for 100% energy independence or even being energy positive |
US10495065B2 (en) * | 2017-05-03 | 2019-12-03 | William O. Fortner | Multi-turbine platform tower assembly and related methods systems, and apparatus |
US10767616B2 (en) | 2018-06-20 | 2020-09-08 | SJK Energy Solutions, LLC | Kinetic fluid energy conversion system |
FR3097277B1 (en) * | 2019-06-13 | 2021-06-25 | Alizen Energie Durable | Wind turbine and energy conversion facility comprising such a wind turbine |
WO2021127663A2 (en) | 2019-12-19 | 2021-06-24 | Sjk Energy Solutions | Kinetic fluid energy conversion system |
GB2613846A (en) * | 2021-12-16 | 2023-06-21 | World Wide Wind Tech As | A wind turbine and a wind power plant |
Citations (23)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US372148A (en) * | 1887-10-25 | Windmill | ||
US3920354A (en) * | 1974-08-30 | 1975-11-18 | Bert J Decker | Horizontal hinged-flap windmill |
US4052134A (en) * | 1976-01-15 | 1977-10-04 | Rollin Douglas Rumsey | Vertical axis wind turbine motor |
US4237384A (en) * | 1979-06-27 | 1980-12-02 | Kennon Woodrow A | Wind turbine means |
US4456429A (en) * | 1982-03-15 | 1984-06-26 | Kelland Robert E | Wind turbine |
US4474529A (en) * | 1983-03-21 | 1984-10-02 | Kinsey Lewis R | Windmill |
US4850792A (en) * | 1985-03-29 | 1989-07-25 | Yeoman David R | Wind turbine |
US5083039A (en) * | 1991-02-01 | 1992-01-21 | U.S. Windpower, Inc. | Variable speed wind turbine |
US5391926A (en) * | 1992-08-18 | 1995-02-21 | Staley; Frederick J. | Wind turbine particularly suited for high-wind conditions |
US5503530A (en) * | 1993-10-07 | 1996-04-02 | Walters; Victor R. | Walter's whirl-wind vertical axis wind turbine |
US5947678A (en) * | 1998-06-30 | 1999-09-07 | Bergstein; Frank D. | Water wheel with cylindrical blades |
US6191496B1 (en) * | 1998-12-01 | 2001-02-20 | Dillyn M. Elder | Wind turbine system |
US6538340B2 (en) * | 2001-08-06 | 2003-03-25 | Headwinds Corporation | Wind turbine system |
US20040047732A1 (en) * | 2002-09-11 | 2004-03-11 | Sikes George W | Dynamo |
US20050042095A1 (en) * | 2003-08-20 | 2005-02-24 | Arthur Kaliski | Self regulating rotor |
US7160083B2 (en) * | 2003-02-03 | 2007-01-09 | General Electric Company | Method and apparatus for wind turbine rotor load control |
US7355294B2 (en) * | 2006-05-22 | 2008-04-08 | General Electric Company | Method and system for wind turbine blade movement |
US20080150292A1 (en) * | 2006-12-21 | 2008-06-26 | Green Energy Technologies, Inc. | Shrouded wind turbine system with yaw control |
US7540705B2 (en) * | 2006-02-01 | 2009-06-02 | Emshey Garry | Horizontal multi-blade wind turbine |
US20090142192A1 (en) * | 2007-10-09 | 2009-06-04 | General Electric Company | Wind turbine metrology system |
US7713020B2 (en) * | 2003-07-11 | 2010-05-11 | Aaron Davidson | Extracting energy from flowing fluids |
US20100129219A1 (en) * | 2008-11-21 | 2010-05-27 | Satwant Grewal | Systems and Methods for Generating Energy Using Wind Power |
US20100251539A1 (en) * | 2006-07-18 | 2010-10-07 | Danotek Motion Technologies | Slow-speed direct-drive generator |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4012163A (en) * | 1975-09-08 | 1977-03-15 | Franklin W. Baumgartner | Wind driven power generator |
JP4434661B2 (en) * | 2003-08-11 | 2010-03-17 | 富士重工業株式会社 | Horizontal axis wind turbine and wind-up angle measurement method |
US20080007068A1 (en) * | 2006-07-10 | 2008-01-10 | Rogers Ward | Spherical wind turbine for generating electricity |
KR100810990B1 (en) * | 2006-10-18 | 2008-03-11 | 주식회사 에어로네트 | Power generation system having vertical wind turbine of jet-wheel type for wind power |
ES2345645B1 (en) * | 2008-06-09 | 2011-07-13 | GAMESA INNOVATION & TECHNOLOGY, S.L. | INSTALLATION OF WIND ENERGY AND PROCEDURE OF MODIFICATION OF THE SHOVEL PASSAGE IN A WIND ENERGY INSTALLATION. |
CN102187095A (en) | 2008-08-22 | 2011-09-14 | 自然动力概念公司 | Column structure with protected turbine |
US8487470B2 (en) * | 2009-05-22 | 2013-07-16 | Derek Grassman | Vertical axis wind turbine and generator therefore |
US20130119662A1 (en) | 2010-03-15 | 2013-05-16 | II Andrew Carlton Thacker | Wind turbine control |
US20110158787A1 (en) | 2010-03-15 | 2011-06-30 | Thacker Ii Andrew Carlton | Wind turbine |
-
2011
- 2011-03-03 US US13/039,951 patent/US20110158787A1/en not_active Abandoned
- 2011-03-03 US US13/039,954 patent/US20110156392A1/en not_active Abandoned
- 2011-03-11 WO PCT/US2011/028161 patent/WO2011115845A1/en active Application Filing
- 2011-03-11 WO PCT/US2011/028158 patent/WO2011115843A1/en active Application Filing
- 2011-03-11 US US13/635,612 patent/US8894348B2/en not_active Expired - Fee Related
Patent Citations (25)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US372148A (en) * | 1887-10-25 | Windmill | ||
US3920354A (en) * | 1974-08-30 | 1975-11-18 | Bert J Decker | Horizontal hinged-flap windmill |
US4052134A (en) * | 1976-01-15 | 1977-10-04 | Rollin Douglas Rumsey | Vertical axis wind turbine motor |
US4237384A (en) * | 1979-06-27 | 1980-12-02 | Kennon Woodrow A | Wind turbine means |
US4456429A (en) * | 1982-03-15 | 1984-06-26 | Kelland Robert E | Wind turbine |
US4474529A (en) * | 1983-03-21 | 1984-10-02 | Kinsey Lewis R | Windmill |
US4850792A (en) * | 1985-03-29 | 1989-07-25 | Yeoman David R | Wind turbine |
US5083039A (en) * | 1991-02-01 | 1992-01-21 | U.S. Windpower, Inc. | Variable speed wind turbine |
US5083039B1 (en) * | 1991-02-01 | 1999-11-16 | Zond Energy Systems Inc | Variable speed wind turbine |
US5391926A (en) * | 1992-08-18 | 1995-02-21 | Staley; Frederick J. | Wind turbine particularly suited for high-wind conditions |
US5503530A (en) * | 1993-10-07 | 1996-04-02 | Walters; Victor R. | Walter's whirl-wind vertical axis wind turbine |
US5947678A (en) * | 1998-06-30 | 1999-09-07 | Bergstein; Frank D. | Water wheel with cylindrical blades |
US6191496B1 (en) * | 1998-12-01 | 2001-02-20 | Dillyn M. Elder | Wind turbine system |
US6538340B2 (en) * | 2001-08-06 | 2003-03-25 | Headwinds Corporation | Wind turbine system |
US20040047732A1 (en) * | 2002-09-11 | 2004-03-11 | Sikes George W | Dynamo |
US6808366B2 (en) * | 2002-09-11 | 2004-10-26 | Vertical Wind Turbine Technologies, LLC | Fluid flow powered dynamo with lobed rotors |
US7160083B2 (en) * | 2003-02-03 | 2007-01-09 | General Electric Company | Method and apparatus for wind turbine rotor load control |
US7713020B2 (en) * | 2003-07-11 | 2010-05-11 | Aaron Davidson | Extracting energy from flowing fluids |
US20050042095A1 (en) * | 2003-08-20 | 2005-02-24 | Arthur Kaliski | Self regulating rotor |
US7540705B2 (en) * | 2006-02-01 | 2009-06-02 | Emshey Garry | Horizontal multi-blade wind turbine |
US7355294B2 (en) * | 2006-05-22 | 2008-04-08 | General Electric Company | Method and system for wind turbine blade movement |
US20100251539A1 (en) * | 2006-07-18 | 2010-10-07 | Danotek Motion Technologies | Slow-speed direct-drive generator |
US20080150292A1 (en) * | 2006-12-21 | 2008-06-26 | Green Energy Technologies, Inc. | Shrouded wind turbine system with yaw control |
US20090142192A1 (en) * | 2007-10-09 | 2009-06-04 | General Electric Company | Wind turbine metrology system |
US20100129219A1 (en) * | 2008-11-21 | 2010-05-27 | Satwant Grewal | Systems and Methods for Generating Energy Using Wind Power |
Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20110049894A1 (en) * | 2006-10-06 | 2011-03-03 | Green William M | Electricity Generating Assembly |
US8894348B2 (en) | 2010-03-15 | 2014-11-25 | II Andrew Carlton Thacker | Wind turbine |
US20120074701A1 (en) * | 2010-09-24 | 2012-03-29 | Frank Hernandez | Ridge cap wind generation system |
US20120061965A1 (en) * | 2011-11-21 | 2012-03-15 | Khedekar Samit A | Vertical axis wind turbine with electronically controlled assisted start mechanism and controlled airflow |
US8482144B2 (en) * | 2011-11-21 | 2013-07-09 | Samit A. Khedekar | Vertical axis wind turbine with electronically controlled assisted start mechanism and controlled airflow |
US20160153308A1 (en) * | 2013-07-31 | 2016-06-02 | Claudio MUNERATO | Auxiliary generator of electrical energy |
US10138753B2 (en) * | 2013-07-31 | 2018-11-27 | Claudio MUNERATO | Auxiliary fluid driven electric generator |
US20150098795A1 (en) * | 2013-10-08 | 2015-04-09 | Aurelio Izquierdo Gonzalez | Vertical-Axis Wind Turbine With Protective Screen |
US9689372B2 (en) * | 2013-10-08 | 2017-06-27 | Aurelio Izquierdo Gonzalez | Vertical-axis wind turbine with protective screen |
DE102019100208A1 (en) * | 2019-01-07 | 2020-07-09 | Dirk Petersen | Vertical wind turbine |
US11085303B1 (en) * | 2020-06-16 | 2021-08-10 | General Electric Company | Pressurized damping fluid injection for damping turbine blade vibration |
Also Published As
Publication number | Publication date |
---|---|
WO2011115845A1 (en) | 2011-09-22 |
US20110156392A1 (en) | 2011-06-30 |
US8894348B2 (en) | 2014-11-25 |
US20130129472A1 (en) | 2013-05-23 |
WO2011115843A1 (en) | 2011-09-22 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US8894348B2 (en) | Wind turbine | |
US8164210B2 (en) | Vertical axis wind turbine with angled braces | |
US7696635B2 (en) | Gravity-flap, savonius-type wind turbine device | |
US20100032954A1 (en) | Wind turbine | |
Tong | Fundamentals of wind energy | |
US9024463B2 (en) | Vertical axis wind turbine with multiple flap vanes | |
US20100135768A1 (en) | Column structure with protected turbine | |
EP2893186B1 (en) | Vertical axis wind turbine | |
Chong et al. | Cross-axis-wind-turbine: a complementary design to push the limit of wind turbine technology | |
US8604635B2 (en) | Vertical axis wind turbine for energy storage | |
US20130119662A1 (en) | Wind turbine control | |
KR101338122B1 (en) | Floating wind power generation with passive yawing damper | |
JP3201957U (en) | Vertical axis wind turbine generator with integrated containment flywheel | |
US20140175801A1 (en) | Wind turbine power generator | |
US9217421B1 (en) | Modified drag based wind turbine design with sails | |
WO2019177919A1 (en) | Systems and methods for maximizing wind energy | |
TWI722445B (en) | Wind power generation system | |
WO2011008179A2 (en) | A vertical axis turbine | |
Acosta et al. | Advance high efficient aerodynamic blades for vertical axis wind turbine modular aggregate | |
KR20120103211A (en) | Wind power plant system using gases with coriolis effect | |
Kulkarni et al. | Comprehensive Evaluation of Some Innovative Wind Turbines | |
JP2023115436A (en) | Power generation and spring device for generating power during breeze at which large blades do not generate power by mounting double large and small blades and bidirectional lens type small generator to hub or nacelle portion in order to increase power generation efficiency of large-scale onshore or offshore large wind power generation facility, and for activating large blades during weak wind by applying elastic sparing like cell motor, and power generation efficiency with energy accumulation linked to seismic isolation facility and reaction energy, as well as small, inexpensive and powerful urban wind power generation device capable of being easily installed even on median strip and above or below bridge and capable of being used even in home and company in future | |
Tilvaldyev | Investigating advance aerodynamic blades of wind turbines for electricity generation from renewable sources of energy | |
Ajao et al. | Interface for modeling the power output of a small wind turbine | |
Prakash et al. | Horizontal Axis Wind Turbine |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |