Natural Fluid Current Patents (Class 416/41)
  • Patent number: 7204674
    Abstract: A rotor for a wind power installation having at least one rotor blade. The smaller the surface area on which the wind acts, that is to say in particular the rotor blade area, the correspondingly lower is the load level for which installation has to be designed and the correspondingly more easily can the rotor blade be transported. On the other hand the size of the wind power installation entails minimum dimensions which are unavoidable for operation and below which the installation dimensions may not fall. In order to provide a rotor blade which on the one hand has the aerodynamically required surface area but which on the other hand is so designed that the surface area of the rotor blade and therewith the depth thereof can be reduced in predetermined situations a part of the surface of the rotor blade is deformmable or movable.
    Type: Grant
    Filed: December 20, 2001
    Date of Patent: April 17, 2007
    Inventor: Aloys Wobben
  • Patent number: 7204673
    Abstract: A method for controlling a wind power installation at very high wind speeds, in which there is predetermined a first wind speed at which the rotor blades of the wind power installation are put into a first predetermined setting. In addition, the method includes controlling the wind power installation during an extreme wind situation where the rotor blades moved to a position to reduce, as far as possible, mechanical loadings on the wind power installation caused by the extreme wind situation.
    Type: Grant
    Filed: November 15, 2001
    Date of Patent: April 17, 2007
    Inventor: Aloys Wobben
  • Patent number: 7175389
    Abstract: A method for reducing peak loads of wind turbines in a changing wind environment includes measuring or estimating an instantaneous wind speed and direction at the wind turbine and determining a yaw error of the wind turbine relative to the measured instantaneous wind direction. The method further includes comparing the yaw error to a yaw error trigger that has different values at different wind speeds and shutting down the wind turbine when the yaw error exceeds the yaw error trigger corresponding to the measured or estimated instantaneous wind speed.
    Type: Grant
    Filed: June 30, 2004
    Date of Patent: February 13, 2007
    Assignee: General Electric Company
    Inventor: Emilian Mieczyslaw Moroz
  • Patent number: 7131812
    Abstract: A sky turbine, having impeller blades with a plurality of panels that can telescope inward and outward. The pitch of the panels can be adjusted, and the pitch of each panel on a blade, passing from the innermost panel to the outermost panel, differs from the pitch of the previous panel by a certain adjustable amount. The sky turbine is preferably mounted above a city at a sufficiently high elevation that air current will be generally faster than just above the ground. In the preferred embodiments, a wing with two pods is pivotally mounted on a tower. Each pod has front and rear shafts, from which four blades extend. Servomotors cause the wing to turn so that its center of symmetry is parallel to the direction the sky is moving, cause the pitch of the panels of the blades to change, and cause the panels of the blades to telescope.
    Type: Grant
    Filed: December 1, 2005
    Date of Patent: November 7, 2006
    Inventor: Manfred Karl Brueckner
  • Patent number: 7121795
    Abstract: A method for reducing at least one of loads, deflections of rotor blades, or peak rotational speed of a wind turbine includes storing recent historical pitch related data, wind related data, or both. The stored recent historical data is analyzed to determine at least one of whether rapid pitching is occurring or whether wind speed decreases are occurring. A minimum pitch, a pitch rate limit, or both are imposed on pitch angle controls of the rotor blades conditioned upon results of the analysis.
    Type: Grant
    Filed: June 30, 2004
    Date of Patent: October 17, 2006
    Assignee: General Electric Company
    Inventors: Emilian Mieczyslaw Moroz, Kirk Gee Pierce
  • Patent number: 7118341
    Abstract: A vertical shaft is provided and supported whereupon are mounted sails that can so self adjust as to interact with the wind in such a way as to power a windmill as well as relieve themselves from winds that are too severe while maintaining continuous operation.
    Type: Grant
    Filed: March 4, 2004
    Date of Patent: October 10, 2006
    Inventor: Delbert Lee Hartman
  • Patent number: 7118338
    Abstract: A method for controlling a wind turbine having twist bend coupled rotor blades on a rotor mechanically coupled to a generator includes determining a speed of a rotor blade tip of the wind turbine, measuring a current twist distribution and current blade loading, and adjusting a torque of a generator to change the speed of the rotor blade tip to thereby increase an energy capture power coefficient of the wind turbine.
    Type: Grant
    Filed: June 30, 2004
    Date of Patent: October 10, 2006
    Assignee: General Electric Company
    Inventors: Emilian Mieczyslaw Moroz, David Lawrence LeMieux, Kirk Gee Pierce
  • Patent number: 7086835
    Abstract: A horizontal axis wind turbine includes: a yaw sensor; a rotor rotating around a rotor axis extending in a substantially horizontal direction, the rotor axis rotating in a substantially horizontal plane depending on wind direction; a plate-like member disposed on a rotational central portion of the rotor and extending in a parallel direction to the rotor axis and in a vertical direction; two anemometers disposed at positions which are across the plate-like member; and a controller for yaw control based on a difference or a ratio between wind speeds measured by the two anemometers.
    Type: Grant
    Filed: August 4, 2004
    Date of Patent: August 8, 2006
    Assignee: Fuji Jukogyo Kabushiki Kaisha
    Inventor: Shigeo Yoshida
  • Patent number: 7059833
    Abstract: A method for the improvement of wind turbine rotor efficiency blades of a wind turbine rotor with serrated trailing edges each having a plurality of span-wise, periodic indentations, in the form of saw teeth having approximately 60 degrees included angles between adjacent vertices. The efficiency of an existing wind turbine rotor is improved by the attachment of an apparatus to at least part of the trailing edge of the wind turbine blades, the apparatus being in the form of a serrated panel that is fixed to the surface of the blade and has the serrations extending into the airflow behind the trailing edge of the existing blade. The efficiency of a new wind turbine blade is improved by manufacturing the blade with serrations of at least part of the trailing edge of the wind turbine blade.
    Type: Grant
    Filed: November 26, 2001
    Date of Patent: June 13, 2006
    Assignee: Bonus Energy A/S
    Inventors: Henrik Stiesdal, Peder Bay Enevoldsen
  • Patent number: 6984110
    Abstract: Disclosed is a wind power generating apparatus in which windmill blades are mounted in a multi-stage fashion to a rotating shaft while being spaced apart from one another to efficiently generate wind power. Each windmill blade includes blade bodies mounted to the rotating shaft, and provided with wind pressure adjusting holes, wind pressure adjusting plates coupled to each blade body, and connected together to a wire, each wind pressure adjusting plate being slidable along guides respectively arranged at opposite sides of the associated wind pressure adjusting hole to adjust an opening degree of the wind pressure adjusting hole, elastic members each adapted to connect one end of the associated wire to the associated blade body, and winches each adapted to connect the other end of the associated blade body, the winches being mounted to a single shaft to simultaneously wind or unwind all wire.
    Type: Grant
    Filed: September 18, 2002
    Date of Patent: January 10, 2006
    Inventor: Keun-Suk Jang
  • Patent number: 6962478
    Abstract: A vertical axis windmill has an immovable, hollow circumferential frame having a plurality of peripheral openings, and rotatable turbine arranged inside the frame and connectable to a generator of electric energy, the turbine having a plurality of vanes each having a working side and a non-working side, and a plurality of gate elements turnably connected with the frame for closing and opening of the openings of the frame by wind flowing substantially in a horizontal plane, the gate elements and the vanes of the turbine being formed so that at one side of the frame the wind opens the gate members by turning them in a predetermined direction, so that at one side the wind turns the gate elements so as to open corresponding ones of the openings, enters the frame through the corresponding opened openings and acts on the working side of corresponding ones of the vanes so as to rotate the turbine in the predetermined direction, while at the same time at the other side of the frame the wind closes other offset gate m
    Type: Grant
    Filed: February 7, 2003
    Date of Patent: November 8, 2005
    Inventor: Michael Tsipov
  • Patent number: 6890152
    Abstract: Methods and Apparatuses for deicing a wind turbine blade are described herein. In one embodiment, an exemplary process includes detecting an icy condition on a wind turbine blade and causing at least a portion of the wind turbine blade to vibrate, causing the ice built up on the wind turbine blade to break off.
    Type: Grant
    Filed: October 3, 2003
    Date of Patent: May 10, 2005
    Assignee: General Electric Company
    Inventor: Bo Thisted
  • Patent number: 6857846
    Abstract: A stackable, vertical axis windmill comprised of a braced external frame that enables stacking of multiple windmill assemblies. Couplings are located on both ends of the vertical rotor shaft to enable stacking and the transmission of power, an internal wind flow cavity, and controlled wind guides is described. The external frame includes structural bracing that allows for two or more windmill to be stacked one upon another to optimize the use of land or rooftop space for the generation of electricity from wind power. The computer controlled wind guides automatically close partially in high wind conditions in order to prevent damage to the windmill. The internal wind flow cavity allows wind to transfer power to both the windward and leeward rotors blades. The rotor axis is constructed so that all bearings can be replaced without dismantling the structure.
    Type: Grant
    Filed: June 19, 2002
    Date of Patent: February 22, 2005
    Inventor: Lewis H. Miller
  • Patent number: 6769873
    Abstract: A dynamically reconfigurable wind turbine blade assembly includes a plurality of reconfigurable blades mounted on a hub, an actuator fixed to each of the blades and adapted to effect the reconfiguration thereof, and an actuator power regulator for regulating electrical power supplied to the actuators. A control computer accepts signals indicative of current wind conditions and blade configuration, and sends commands to the actuator power regulator. Sensors measure current wind conditions and current configurations and speed of the blades. An electrical generator supplies electrical power to the assembly. Data from the sensors is fed to the control computer which commands the actuator power regulator to energize the actuators to reconfigure the blades for optimum performance under current wind conditions.
    Type: Grant
    Filed: October 8, 2002
    Date of Patent: August 3, 2004
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Charles H. Beauchamp, Stephen J. Plunkett, Stephen A. Huyer
  • Patent number: 6749399
    Abstract: A wind turbine with an array of rotors arranged at various heights. Each rotor is optimized for the height at which it is located. Optimization of each rotor could include selection of rated power, solidity, tip speed, blade twist, blade taper, or rotor diameter. Each rotor can also be operated in a manner that is optimized for the wind speed it experiences. Optimized operation parameters could include blade pitch angle or rotor speed.
    Type: Grant
    Filed: March 7, 2002
    Date of Patent: June 15, 2004
    Assignee: Ocean Wind Energy Systems
    Inventor: William E. Heronemus
  • Publication number: 20040067134
    Abstract: A dynamically reconfigurable wind turbine blade assembly includes a plurality of reconfigurable blades mounted on a hub, an actuator fixed to each of the blades and adapted to effect the reconfiguration thereof, and an actuator power regulator for regulating electrical power supplied to the actuators. A control computer accepts signals indicative of current wind conditions and blade configuration, and sends commands to the actuator power regulator. Sensors measure current wind conditions and current configurations and speed of the blades. An electrical generator supplies electrical power to the assembly. Data from the sensors is fed to the control computer which commands the actuator power regulator to energize the actuators to reconfigure the blades for optimum performance under current wind conditions.
    Type: Application
    Filed: October 8, 2002
    Publication date: April 8, 2004
    Inventors: Charles H. Beauchamp, Stephen J. Plunkett, Stephen A. Huyer
  • Publication number: 20030170123
    Abstract: A wind turbine with an array of rotors arranged at various heights. Each rotor is optimized for the height at which it is located. Optimization of each rotor could include selection of rated power, solidity, tip speed, blade twist, blade taper, or rotor diameter. Each rotor can also be operated in a manner that is optimized for the wind speed it experiences. Optimized operation parameters could include blade pitch angle or rotor speed.
    Type: Application
    Filed: March 7, 2002
    Publication date: September 11, 2003
    Inventor: William E. Heronemus
  • Patent number: 6402472
    Abstract: A sail-type windmill wheel is provided in which the area of the wheel facing into the wind is adjusted by an automatic variation of the blade angle of the sails. The wind wheel comprises a hub (22) with a plurality of radially extending spars (18), substantially triangular sails (10) secured along one edge to said arms, the clew of said sails secured through a sheeting cable (24) to drawbar extension springs (28), and the drawbar extension springs secured to the tip of the next adjacent arm. During high wind speeds the automatic blade angle adjustment reduces the frontal area of the wind wheel with a corresponding reduction in the force of the wind upon the wheel. During normal working wind speeds the present invention maintains the sails within an optimum blade angle range for extracting energy from the wind.
    Type: Grant
    Filed: November 8, 2000
    Date of Patent: June 11, 2002
    Inventors: Allan Curtis Hogue, Jeanette Diane Hogue
  • Publication number: 20010035651
    Abstract: A hub, to which three blades 3 receiving wind are fixed so as to extend in a radial direction of the hub at equal intervals, is arranged in a spindle-shaped boss having a rectification function. A cylindrical frame is arranged on the leeward side of the boss to separate an outer peripheral surface of a generator from outside air. An outer surface of the boss, which rotates with the blades, and an outer peripheral surface of the frame form a continuous plane. On the outer peripheral surface of the frame, a plurality of fins, which are outwardly protruded in a radial direction of the frame and extend in an axial direction of the frame, are arranged in a circle-circumferential direction of the frame at equal intervals. After the outside air gives a rotational force to the blades, the outside air passes along the fins. Therefore, heat, which is generated in the generator and is transferred to the fins through the frame by conduction, is dissipated to the outside air.
    Type: Application
    Filed: April 23, 2001
    Publication date: November 1, 2001
    Inventors: Toshiyuki Umemoto, Yuji Ikeda, Ryoji Nagatani, Satoru Kotoh
  • Patent number: 5599168
    Abstract: A wind turbine apparatus having a frame assembly consisting of a hub and an outer rim interconnected by a series of spokes. Several wind vanes are rotatably secured within the frame assembly so as to extend from the hub radially outwardly around the frame assembly. Each wind vane consists of an impeller and an impeller shaft, the impeller shaft being positioned so that it does not pass through the center of wind moment of the impeller. Thus, when a wind vector reaches the impeller, the impeller and shaft rotate in direct accordance with the wind's velocity, thus ensuring that the impeller faces optimally into the wind. A biasing device is attached to each impeller shaft, the biasing device serving to retard the rotation of the wind vanes when the wind vector exceeds a given velocity, thus ensuring that the impellers maintain a constant rotational speed. A link means interconnects the adjacent impeller shafts so as to ensure that the wind vanes rotate simultaneously.
    Type: Grant
    Filed: August 23, 1995
    Date of Patent: February 4, 1997
    Inventor: Arnold M. Lund
  • Patent number: 5584655
    Abstract: A wine turbine with blades having a high lift-to-drag ratio is provided. A hydraulic or other control system is used to control cone angle, such as in response to flap moment. Pitch of blades is controlled, such as in relation to the blade flap angle. Teeter motion is controlled preferably as a function of teeter angular velocity.
    Type: Grant
    Filed: December 21, 1994
    Date of Patent: December 17, 1996
    Assignee: The Wind Turbine Company
    Inventor: Kenneth J. Deering
  • Patent number: 4877374
    Abstract: A windmill is provided which automatically compensates for increased wind velocity, causing the blades to feather and rotate at a substantially constant velocity rather than overspeeding. This is accomplished by pivotally mounting the blades so that they are rotatable between positions of relatively high angle with respect to the direction of the wind and positions of relatively shallow angle, with a resilient means biasing them to the former position. Tabs projecting forwardly at obtuse angles from the outer ends of the leading edges of the blades cause the blades to be pivoted to the feathered position when wind velocity increases.
    Type: Grant
    Filed: January 23, 1989
    Date of Patent: October 31, 1989
    Inventor: Bill Burkett
  • Patent number: 4850792
    Abstract: A vertical axis wind turbine includes a pair of wind deflectors for directing the wind current into the rotor assembly. The wind deflectors are connected to the wind turbine so that their positions are automatically adjusted as a function of wind velocity as well as wind direction to maximize efficiency. The wind deflectors automatically move to a position downwind of the rotor assembly during periods of unusually high wind velocity and actuate a rotational governor which increases the angular inertia of the turbine to limit the speed of the turbine shaft during such high wind conditions.
    Type: Grant
    Filed: March 23, 1987
    Date of Patent: July 25, 1989
    Inventor: David R. Yeoman
  • Patent number: 4815936
    Abstract: According to the invention, a wind turbine 10 incorporates a wind vane 105 which mechanically controls a valve 100 that directs the output of a turbine driven hydraulic pump 75 to yaw the turbine out of the wind upon a loss of system power or load. The turbine yaws out of the wind at an angular rate that is roughly proportional to rotor speed so that excessive teeter amplitudes are not encountered. The mechanically driven pump advantageously provides power to yaw the rotor out of the wind even if all electrical power is lost.
    Type: Grant
    Filed: July 5, 1988
    Date of Patent: March 28, 1989
    Assignee: United Technologies Corporation
    Inventors: Christopher L. Stoltze, Joel E. Parker
  • Patent number: 4678394
    Abstract: The self-governing energy panel is to be used as one of a group of panels designed to collect wind for and govern the speed of the windpowered traveling shaft machine. This machine is designed to convert windpower into other forms of energy (e.g. electricity or direct-drive) by connection to a generator or other device. The panel is hung on bearings that are on the support beams that protrude out from the horizontal shaft of the windpowered traveling shaft machine. The panel has the majority of its length below the bearings; however, there are several places the panel may be attached to the beams thus changing how much of the panel is above or below the bearings. The panel will hang vertically to the ground in calm periods but with increasing wind speed the panel can change to a completely horizontal position by rotating on the bearings.
    Type: Grant
    Filed: July 30, 1985
    Date of Patent: July 7, 1987
    Inventor: Francis E. Willoughby
  • Patent number: 4652206
    Abstract: A vertical axis wind turbine includes a pair of wind deflectors for directing the wind current into the rotor assembly. The wind deflectors are connected to the wind turbine so that their positions are automatically adjusted as a function of wind velocity as well as wind direction to maximize efficiency. The wind deflectors automatically move to a position downwind of the rotor assembly during periods of unusually high wind velocity and actuate a rotational governor which increases the angular inertia of the turbine to limit the speed of the turbine shaft during such high wind conditions.
    Type: Grant
    Filed: March 29, 1985
    Date of Patent: March 24, 1987
    Inventor: David R. Yeoman
  • Patent number: 4632637
    Abstract: A high speed, downwind horizontal axis wind turbine includes three circumferentially spaced lightweight blades having inner support arms and radially outwardly disposed airfoil configured blade segments which are pivotally connected to the support arms, so as to fold straight downwind under high wind conditions or high rotating speeds. A spring biased control mechanism serves to rotate the airfoil segment of each blade about its longitudinal axis as the blade is folded downwind, so that a simultaneous folding and feathering action is obtained to prevent damage to the turbine in high wind conditions or under high rotating speeds.
    Type: Grant
    Filed: June 7, 1984
    Date of Patent: December 30, 1986
    Assignee: Analytics, Inc.
    Inventor: Ray F. Traudt
  • Patent number: 4630996
    Abstract: Disclosed is a windmill whose impeller and strut are protected from harms by high wind, comprising an impeller; a strut; weight; and means for supporting said strut in such a manner that said strut is capable of rotating and inclining around pivot, wherein said impeller and weight are installed at different sides of said strut, and wherein said strut is supported by said means at the pivot located between said impeller and the center of gravity.
    Type: Grant
    Filed: September 10, 1984
    Date of Patent: December 23, 1986
    Assignee: Ken Hayashibara
    Inventor: Kazumi Masaki
  • Patent number: 4575309
    Abstract: A wind turbine having the tips of the blades pivotable to a position in which they act as brakes to slow the turbine down. The pivoting is caused by relative axial movement of the tip and main blade portions which is caused by the action of a spring. The spring action is normally overcome by a hydraulic actuator 16. When the hydraulic pressure exceeds a threshold value corresponding to a desired limit rotational speed of the turbine a pressure switch 83 causes a pressure release valve 84 to dump the fluid pressure in the hydraulic actuator 16, thus allowing the spring to operate and cause the pivoting of the tip.
    Type: Grant
    Filed: May 22, 1984
    Date of Patent: March 11, 1986
    Assignee: James Howden & Company Ltd.
    Inventor: Allan W. Brown
  • Patent number: 4571156
    Abstract: An air foil which is coupled to a wind energy conversion machine is provided with a flexible and resilent trailing spoiler that limits the rotational speed of the machine and prevents overspeeding. The trailing spoiler is a flexible and resilient sheet that is laminated to the upwind side of a rigid blade so that a portion of the sheet extends past the trailing edge of the blade. The portion of the sheet that extends past the trailing edge bends towards the wind during high wind conditions to prevent overspeeding of the machine.
    Type: Grant
    Filed: March 5, 1984
    Date of Patent: February 18, 1986
    Assignee: D. C. Research, Inc.
    Inventor: Francis M. Penterman
  • Patent number: 4551066
    Abstract: A water wheel for operating fully submerged in an ocean current has a rotating frame member supported on the ocean floor for rotation about a vertical axis. The frame member supports a plurality of vertically extending vanes, each vane being rotatably supported on the frame for limited rotation about a vertical axis. It has a hydrofoil shape in cross-section with the axis of rotation parallel to the leading and trailing edges. Rotation of the vanes is limited relative to the frame by a hydraulic piston control system and shock absorbers.
    Type: Grant
    Filed: March 7, 1983
    Date of Patent: November 5, 1985
    Inventor: James O. Frisz
  • Patent number: 4518312
    Abstract: An improvement of the device disclosed in U.S. Pat. No. 4,297,075 permits the propeller assembly of a wind energy system to swing in two directions, both left and right with respect to wind direction. The improvement includes a snubber assembly which has a plurality of springs mounted on a central bar.
    Type: Grant
    Filed: March 7, 1983
    Date of Patent: May 21, 1985
    Assignee: Jacobs Wind Electric
    Inventors: Marcellus L. Jacobs, Paul R. Jacobs
  • Patent number: 4515525
    Abstract: Yaw (fishtail) oscillations in large wind turbines (10) are minimized by damping provided by a drive motor (65) connecting the turbine to the supporting tower (50) therefor at, for example, a yaw bearing (45). The drive motor drives the wind turbine in yaw and maintains desired yaw settings of the turbine. The motor is also capable of being driven by yaw oscillations of the wind turbine and in being so driven, dissipates the energy of such oscillations.
    Type: Grant
    Filed: November 8, 1982
    Date of Patent: May 7, 1985
    Assignee: United Technologies Corporation
    Inventor: Glidden S. Doman
  • Patent number: 4503673
    Abstract: Normally feathered propeller blades of a wind power generating system unfeather in response to the actuation of a power cylinder that responds to actuating signals. Once operational, the propellers generate power over a large range of wind velocities. A maximum power generation design point signals a feather response of the propellers so that once the design point is reached no increase in power results, but the system still generates power. At wind speeds below this maximum point, propeller speed and power output optimize to preset values. The propellers drive a positive displacement pump that in turn drives a positive displacement motor of the swash plate type. The displacement of the motor varies depending on the load on the system, with increasing displacement resulting in increasing propeller speeds, and the converse.
    Type: Grant
    Filed: May 25, 1979
    Date of Patent: March 12, 1985
    Inventors: Charles Schachle, Patrick J. Schachle, Edward C. Schachle, John R. Schachle
  • Patent number: 4504192
    Abstract: An air jet spoiler arrangement is provided for a Darrieus-type vertical axis wind-powered turbine. Air is drawn into hollow turbine blades through air inlets at the ends thereof and is ejected in the form of air jets through small holes or openings provided along the lengths of the blades. The air jets create flow separation at the surfaces of the turbine blades, thereby inducing stall conditions and reducing the output power. A feedback control unit senses the power output of the turbine and controls the amount of air drawn into the air inlets accordingly.
    Type: Grant
    Filed: September 15, 1983
    Date of Patent: March 12, 1985
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: Jack D. Cyrus, Emil G. Kadlec, Paul C. Klimas
  • Patent number: 4494007
    Abstract: To generate power from wind economically, a feathering vane is pivotally mounted perpendicular to a tail vane and shifts the orientation of a sprocket assembly controlled by the tail vane in response to wind velocity. The sprocket assembly changes the orientation of blades which orbit about and rotate the main power shaft so that, as wind velocity changes, the blade orientations are shifted in a compensating direction under the control of the tail vane. A lever shifts the position of the blades to positions that balance wind power and brake the rotation for maintenance purposes. The speed-control mechanism includes a damper to avoid being excessively affected by wind gusts. The main shaft is connected through a speed increaser which has less mass at the high-speed end than the low-speed end to an induction generator when used for cogeneration, the field of the induction generator being excited by the cogeneration frequency.
    Type: Grant
    Filed: September 2, 1982
    Date of Patent: January 15, 1985
    Assignee: Gaston Manufacturing, Inc.
    Inventor: Everett E. Gaston
  • Patent number: 4490093
    Abstract: A windpower system includes a support and a turbine having a shaft rotatively mounted to the support. The turbine has variable pitch blades whose pitch is controlled by the differential motion of a rotary control shaft coaxial with the turbine shaft and the turbine shaft itself so that the blade pitch can be varied by a stationary motor without requiring any slip rings or other such wear-prone couplings. In the event of a power failure, rotary motion of the control shaft is prevented so that the turbine blades are feathered solely due to the force developed by the rotating turbine. Also, if the turbine is used to generate electrical power, an induction generator coupled to the turbine shaft is employed whose shaft speed is indicative of generator output power.
    Type: Grant
    Filed: July 13, 1981
    Date of Patent: December 25, 1984
    Assignee: U.S. Windpower, Inc.
    Inventors: Allan Chertok, John Gjertsen, Sr., Louis Manfredi
  • Patent number: 4443155
    Abstract: A new type of overspeed control system for a rotor driven by wind or some other fluid flow. The rotor support is mounted so that it can move back some small distance along the direction of the fluid flow, the rotor axis remaining in substantially the same direction during this movement. This backward movement is in response to the thrust generated by the lift and drag forces on the rotor impellers. At a predetermined thrust force, indicating that the rotor is operating in a fluid velocity high enough to cause overspeeding, the backward movement of the rotor engages a brake to slow the rotor. Essential to the invention is the use of the backward movement of the rotor to brake the rotor.
    Type: Grant
    Filed: October 6, 1980
    Date of Patent: April 17, 1984
    Inventor: Donald R. Smith
  • Patent number: 4439105
    Abstract: An offset-axis type wind generator uses a passive cyclic pitch-change rotor whose shaft axis is inclined downward and aft, with its sense of rotation selected so that the yaw component of the shaft torque at least partially of the shaft torque offsets that component of thrust which accompanies power extraction. A wind-alignment vane extends from a boom mounted on a furling hinge, equipped with mechanism to limit the vane's anti-furling moment to balance only the remainder of the moment of rotor thrust. Hence, disengagement of power extraction does not cause the rotor to overspeed, and the machine may idle even in gale-force winds, furled to nearly 90.degree..
    Type: Grant
    Filed: October 2, 1981
    Date of Patent: March 27, 1984
    Assignee: Jerome A. Gross
    Inventor: Kurt H. Hohenemser
  • Patent number: 4435647
    Abstract: Damping of the primary bending mode of a tower (12) mounting a wind turbine having a control (36) for providing a pitch blade angle reference signal (40) to modulate the pitch of the turbine blades (1) through a pitch change mechanism (38) for constant power is provided by generating the pitch blade angle reference signal as the integral (104) of the summation (266) of a torque/power controlling blade pitch angle reference rate signal (98) with an estimated acceleration signal (255) generated by filtering (250, 252, 254) the blade pitch angle reference signal (40) with the following transfer function ##EQU1##
    Type: Grant
    Filed: April 2, 1982
    Date of Patent: March 6, 1984
    Assignee: United Technologies Corporation
    Inventors: Kermit I. Harner, John P. Patrick, Joseph M. Kos
  • Patent number: 4426192
    Abstract: In order to control the turbine speed of a windmill employed for power generation, the pitch of the turbine blades is based on a dual-deadband control strategy. If the current turbine speed is determined to be outside of a relatively wide deadband, action is taken to correct the speed by changing blade pitch accordingly. If the current speed is not outside of the relatively wide deadband, then the average of the turbine speed over a recent interval is compared with a relatively narrow deadband within the wider deadband. Action is then taken to change the blade pitch if the average speed is outside the narrow deadband. In this way, wide excursions of turbine speed are corrected promptly, but the frequency of control actions is minimized by requiring only the average speed to be kept within tight limits.
    Type: Grant
    Filed: February 7, 1983
    Date of Patent: January 17, 1984
    Assignee: U.S. Windpower, Inc.
    Inventors: Allan Chertok, Joel Donahue, William Widnall
  • Patent number: 4420692
    Abstract: An accelerometer (1) disposed on the support tower (12) of a wind turbine electric generating system in the vicinity of the rotor (10, 16) thereof provides a signal (1) indicative of acceleration of the tower in the direction of the rotor rotational axis. The signal (2) is passed through a band-pass filter (4) for summation (9) with a torque/power controlled (100) blade pitch angle reference rate signal (98), the integral (104) of which provides a blade pitch angle reference signal (40) to control the pitch angle of the rotor blades (10) through a pitch change mechanism (38), thereby to provide additional, positive aerodynamic damping to the tower while modulating blade angle for constant torque/power in response to wind turbulence.
    Type: Grant
    Filed: April 2, 1982
    Date of Patent: December 13, 1983
    Assignee: United Technologies Corporation
    Inventors: Joseph M. Kos, John P. Patrick, Kermit I. Harner
  • Patent number: 4406584
    Abstract: A windmill of the vertical axis type having a plurality of circumferentially and radially outwardly spaced rotatably mounted vanes vertically parallel to the axis shaft wherein means are provided for controlling multistage feathering of the vanes in conjunction with said vanes feathering to rotate on their individual axes in a direction opposite to the direction of rotation of the windmill assembly in increments of 45 degrees twice for each blade before finally feathering a final half rotation completing the rotation of 360 degrees on its individual axis while the windmill makes one revolution, thus repeatedly repositioning the blades to the most optimum resistance angle to the wind as the windmill rotates increasing the power angle to near seventy-five percent of the circle of the windmill rotation, a construction option prevailing to routinely cause all the blades to feather when near a zero angular position to the wind, and having associated therewith a conglomerate of mechanical phenomena to perform said
    Type: Grant
    Filed: August 7, 1980
    Date of Patent: September 27, 1983
    Inventor: William J. Stepp
  • Patent number: 4381902
    Abstract: A fiberglass-epoxy flexbeam extends from tip to tip of each opposed blade pair, carrying the blade centrifugal forces so that none of the centrifugal loading is carried by the hub. The primary load-carrying connector between the flexbeam and the hub is a set of elastomeric pads. These provide a soft mount between the flexbeam and the hub to keep the primary bending moments within the flexbeams where the filaments are designed to accommodate them. The elastomeric pads are also effective in isolating the hub from chordwise loads which include the steady driving torque and the "C" mode and "S" modes of coriolis vibration. The elastomeric hub mount damps these vibrations and tunes their frequencies to values well separated from the rotor frequency.
    Type: Grant
    Filed: December 20, 1979
    Date of Patent: May 3, 1983
    Assignee: Hughes Helicopters, Inc.
    Inventors: Robert E. Head, Debashis Banerjee
  • Patent number: 4364708
    Abstract: A windmill having blades with both variable pitch and variable spanwise twist. The windmill includes a hub which may be supported on top of a tower for rotation about a substantially horizontal axis. A plurality of blades are provided, each having a root, a tip and a spanwise twistable intermediate section. Linkage mechanisms connect the roots of the blades to the hub to permit selective independent rotation of the roots and the tips of the blades for varying the pitch and the spanwise twist of the blades. An electric power generator is drivingly connected to the hub. A control mechanism is connected to the linkage mechanisms for varying the pitch and spanwise twist of the blades in accordance with a predetermined desired relationship.
    Type: Grant
    Filed: August 27, 1981
    Date of Patent: December 21, 1982
    Inventor: Constant V. David
  • Patent number: 4362466
    Abstract: A wind-wheel for a wind-operated power generator comprises a rotor shaft, carrying the vanes of the wind-wheel, and mounted at its ends in rotary bearings supported by a frame. The frame is mounted on the top of a tower by means of a support member which itself is rotatable about a vertical axis through the tower. The connection between the support member and the frame enables the frame to be rotated about a horizontal axis below the bottom of the vanes. In a high wind, the wind-wheel can, thus, swing out of the vertical plane, spilling wind from the vanes, to avoid damage.
    Type: Grant
    Filed: July 23, 1980
    Date of Patent: December 7, 1982
    Inventor: Walter Schonball
  • Patent number: 4360315
    Abstract: The present invention relates to wind turbines and more particularly to such a device having a horizontally disposed power output shaft pivotally supported by a turntable. Attached to the output shaft are a number of circumferentially spaced apart blades which are each hinged along their leading edges with the hinge axes inclined obliquely to the longitudinal axis of the shaft. A spring controlled governor is provided to control the pivotal position of each of the blades around their respective hinge axis of rotation.
    Type: Grant
    Filed: April 14, 1980
    Date of Patent: November 23, 1982
    Inventor: Leonard Olson
  • Patent number: 4349315
    Abstract: A system of rotatably and pivotally mounted radially extended bent supports for radially extending windmill rotor vanes in combination with axially movable radially extended control struts connected to the vanes with semi-automatic and automatic torque and other sensing and servo units provide automatic adjustment of the windmill vanes relative to their axes of rotation to produce mechanical output at constant torque or at constant speed or electrical quantities dependent thereon.
    Type: Grant
    Filed: January 11, 1980
    Date of Patent: September 14, 1982
    Assignee: Wind Engineering Corporation
    Inventor: William L. Ducker
  • Patent number: 4335996
    Abstract: Opposing windmill airfoil blades extend from a central hub and are connected thereto by a pair of cables secured to the inner ends of the blades and which each freely engages through the opposite ends of a cross member secured to the hub. These cables then extend to a reel on the hub thus forming a triangular configuration to support each airfoil blade. The reel is driven by a small reversible electric motor which extends and retracts the cables and hence the blades depending upon the tension in the cables which is sensed by a sensor which in turn actuates the electric motor. As the wind speed increases in velocity, the cables lengthen and vice-versa. Guide vanes or control tail wings extend from adjacent the inner ends of each of the airfoil blades and are fixed in manufacture thus automatically presenting the desired angle of attack of the airfoil blades to the wind.
    Type: Grant
    Filed: December 1, 1980
    Date of Patent: June 22, 1982
    Inventor: Joel M. Ross
  • Patent number: 4333018
    Abstract: A wind energy conversion system for converting wind energy into controlled wind turbine torque comprising a wind turbine with an essentially horizontally disposed shaft, a means, rotatably mounted to a chassis, for sensing and reacting to wind turbine torque such that reaction torque acting on the means causes angular displacement of the means, a driven machine drivenly connected to the shaft of the wind turbine, and a means for adjusting wind turbine efficiency which is drivenly connected to the first mentioned means in such a way as to prevent continual angular speed thereof. Angular displacement of the first mentioned means provides the power for the last mentioned means to adjust wind turbine efficiency.
    Type: Grant
    Filed: July 9, 1980
    Date of Patent: June 1, 1982
    Assignee: Ventus Energy Corp.
    Inventor: Gerald W. Bottrell