Google Patentsopen access

Methods for operating a wind turbine — General Electric Company (US8738192B2)

ABSTRACT

Abstract

A method for operating a wind turbine having at least one blade includes determining an ambient air operating envelope and controlling a power output of the wind turbine at least partially based on the determined ambient air operating envelope. Determining an ambient air operating envelope includes measuring at least one of an ambient air temperature, an ambient air pressure, an ambient air humidity, and wind turbine power output. The method also includes comparing at least one of a measured ambient air temperature, a measured ambient air humidity and a measured ambient air pressure to predetermined ambient air temperature, pressure and humidity values. The method further includes referencing the predetermined ambient air temperature, pressure and humidity values to at least one operational parameter of the wind turbine. The method also includes determining if an existing wind turbine power output is within a range associated with the determined ambient air operating envelope.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of U.S. patent application Ser. No. 11/551,884, filed Oct. 23, 2006, which is hereby incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

This invention relates generally to wind turbines, and more specifically to methods and apparatus for controlling operation of a wind turbine.

Generally, a wind turbine includes a rotor having multiple blades. The rotor is sometimes mounted within a housing, or nacelle, that is positioned on top of a base, for example a truss or tubular tower. At least some known electric utility grade wind turbines (i.e., wind turbines designed to provide electrical power to an electric utility grid) can have rotors of 30 meters (m) (98 feet (ft)) or more in diameter. The rotor blades transform mechanical wind energy into a mechanical rotational torque that drives one or more generators. The generators are sometimes, but not always, rotationally coupled to the rotor through a gearbox. The gearbox steps up the inherently low rotational speed of the turbine rotor for the generator to efficiently convert the rotational mechanical energy to electrical energy, which is fed into the electric utility grid. Gearless direct drive wind turbine generators also exist.

Seasonal changes to the ambient air conditions, for example changes to ambient air temperature and/or pressure, may affect performance of at least some known wind turbines. For example, the normal international engineering code (IEC) design envelope of a wind turbine defines loads acting on the wind energy turbine within a temperature range from about +40 degrees Celsius (° C.) (about 100 degrees Fahrenheit (° F.)) to about −20° C. (about −30° F.). Operation of a wind turbine below this temperature range may require new load calculations which will exceed the design load envelope if no countermeasures are taken, possibly resulting in the need of new, reinforced components. At least some known wind turbines, when subjected to cold weather conditions with ambient air temperature values below the lower temperature limit of the allowable temperature range, are shut off, which is disadvantageous insofar as no electric output power is generated.

Another example of seasonal changes affecting wind turbine performance is that air temperature-corrected turbine performance of at least some known wind turbines may be lower in the summer than in the winter. For example, a probability of the rotor blades of at least some known wind turbines to stall increases during summer conditions when ambient air temperatures are typically higher. Such stalling reduces a potential electric power output of the wind turbine. Moreover, reestablishment of airflow around at least some known wind turbine rotor blades after stalling may cause a short-term increase in generator speed and/or electric power output that may be difficult for a controller of the wind turbine to process. Such controller processing difficulty may increase a probability of the wind turbine to be disconnected from an electric grid due to over-speed and/or over-production conditions.

BRIEF DESCRIPTION OF THE INVENTION

In one aspect, a method for operating a wind turbine. The method includes measuring an ambient air temperature and decreasing a power output of the wind turbine if the measured ambient air temperature is below a predetermined limit to thereby facilitate reducing loads acting on components of the wind turbine.

In another aspect, a wind turbine is provided. The wind turbine includes a rotor that includes a hub and at least one rotor blade coupled to the hub. The wind turbine also includes a first sensor configured to measure ambient air temperature and generate and transmit an ambient air temperature signal. The wind turbine further includes at least one processor coupled in electronic data communication to the first sensor. The at least one processor is configured to facilitate reducing loads acting on components of the wind turbine by at least one of receiving a measured ambient air temperature signal from the first sensor and decreasing a power output of the wind turbine if the received ambient air temperature signal is below a predetermined limit.

In a further aspect, a method for operating a wind turbine having at least one blade is provided. The method includes determining an ambient air operating envelope and controlling a power output of the wind turbine at least partially based on the determined ambient air operating envelope.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of an exemplary wind turbine;

FIG. 2 is a schematic view of an exemplary nacelle that may be used with the wind turbine shown in FIG. 1 ;

FIG. 3 is an electrical and electronic schematic diagram of the wind turbine shown in FIG. 1 ;

FIG. 4 is a flowchart illustrating an exemplary method for controlling the wind turbine shown in FIG. 1 ; and

FIG. 5 is a flowchart illustrating another exemplary method for controlling the wind turbine shown in FIG. 1 .

DETAILED DESCRIPTION OF THE INVENTION

As used herein, the term “blade” is intended to be representative of any device that provides reactive force when in motion relative to a surrounding fluid. As used herein, the term “wind turbine” is intended to be representative of any device that generates rotational energy from wind energy, and more specifically, converts kinetic energy of wind into mechanical energy. As used herein, the term “wind turbine generator” is intended to be representative of any wind turbine that generates electrical power from rotational energy generated from wind energy, and more specifically, converts mechanical energy converted from kinetic energy of wind to electrical power. As used herein, the term “windmill” is intended to be representative of any wind turbine that uses rotational energy generated from wind energy, and more specifically mechanical energy converted from kinetic energy of wind, for a predetermined purpose other than generating electrical power, such as, but not limited to, pumping a fluid and/or grinding a substance.

FIG. 1 is a schematic view an exemplary wind turbine 10 . FIG. 2 is a schematic view of an exemplary nacelle 16 that may be used with wind turbine 10 (shown in FIG. 1 ). FIG. 3 is an electrical and electronic schematic diagram of wind turbine 10 (shown in FIG. 1 ). Wind turbine 10 described and illustrated herein is a wind generator for generating electrical power from wind energy. However, in some embodiments, wind turbine 10 may be, in addition or alternative to a wind generator, any type of wind turbine, such as, but not limited to, a windmill (not shown). Moreover, wind turbine 10 described and illustrated herein includes a horizontal-axis configuration. However, in some embodiments, wind turbine 10 may include, in addition or alternative to the horizontal-axis configuration, a vertical-axis configuration (not shown). Wind turbine 10 may be coupled to an electrical load (not shown), such as, but not limited to, a power grid (not shown), for receiving electrical power therefrom to drive operation of wind turbine 10 and/or its associated components and/or for supplying electrical power generated by wind turbine 10 thereto. Although only one wind turbine 10 is shown in FIG. 1-3 , in some embodiments a plurality of wind turbines 10 may be grouped together, sometimes referred to as a “wind farm”.

Wind turbine 10 includes a body 16 , sometimes referred to as a “nacelle”, and a rotor (generally designated by 18 ) coupled to body 16 for rotation with respect to body 16 about an axis of rotation 20 . In the exemplary embodiment, nacelle 16 is mounted on a tower 14 . However, in some embodiments, in addition or alternative to tower-mounted nacelle 16 , wind turbine 10 includes a nacelle 16 adjacent the ground and/or a surface of water. The height of tower 14 may be any suitable height enabling wind turbine 10 to function as described herein. Rotor 18 includes a hub 22 and a plurality of blades 24 (sometimes referred to as “airfoils”) extending radially outwardly from hub 22 for converting wind energy into rotational energy. Although rotor 18 is described and illustrated herein as having three blades 24 , rotor 18 may have any number of blades 24 . Blades 24 may each have any length (whether described herein). For example, in some embodiments one or more rotor blades 24 are about 0.5 meters (m) (1.64 feet (ft)) long, while in some embodiments one or more rotor blades 24 are about 50 m (164 ft) long. Other examples of blade 24 lengths include 10 m (32.8 ft) or less, about 20 m (65.6 ft), about 37 m (121.4 ft), and about 40 m (131.2 ft). Still other examples include rotor blades between about 50 and about 100 meters long (164 ft to 328 ft).

Despite how rotor blades 24 are illustrated in FIG. 1 , rotor 18 may have blades 24 of any shape, and may have blades 24 of any type and/or any configuration, whether such shape, type, and/or configuration is described and/or illustrated herein. One example of another type, shape, and/or configuration of rotor blades 24 is a ducted rotor (not shown) having a turbine (not shown) contained within a duct (not shown). Another example of another type, shape, and/or configuration of rotor blades 24 is a darrieus wind turbine, sometimes referred to as an “eggbeater” turbine. Yet another example of another type, shape, and/or configuration of rotor blades 24 is a savonious wind turbine. Even another example of another type, shape, and/or configuration of rotor blades 24 is a traditional windmill for pumping water, such as, but not limited to, four-bladed rotors having wooden shutters and/or fabric sails. Moreover, wind turbine 10 may, in some embodiments, be a wind turbine wherein rotor</fig

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of U.S. patent application Ser. No. 11/551,884, filed Oct. 23, 2006, which is hereby incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

This invention relates generally to wind turbines, and more specifically to methods and apparatus for controlling operation of a wind turbine.

Generally, a wind turbine includes a rotor having multiple blades. The rotor is sometimes mounted within a housing, or nacelle, that is positioned on top of a base, for example a truss or tubular tower. At least some known electric utility grade wind turbines (i.e., wind turbines designed to provide electrical power to an electric utility grid) can have rotors of 30 meters (m) (98 feet (ft)) or more in diameter. The rotor blades transform mechanical wind energy into a mechanical rotational torque that drives one or more generators. The generators are sometimes, but not always, rotationally coupled to the rotor through a gearbox. The gearbox steps up the inherently low rotational speed of the turbine rotor for the generator to efficiently convert the rotational mechanical energy to electrical energy, which is fed into the electric utility grid. Gearless direct drive wind turbine generators also exist.

Seasonal changes to the ambient air conditions, for example changes to ambient air temperature and/or pressure, may affect performance of at least some known wind turbines. For example, the normal international engineering code (IEC) design envelope of a wind turbine defines loads acting on the wind energy turbine within a temperature range from about +40 degrees Celsius (° C.) (about 100 degrees Fahrenheit (° F.)) to about −20° C. (about −30° F.). Operation of a wind turbine below this temperature range may require new load calculations which will exceed the design load envelope if no countermeasures are taken, possibly resulting in the need of new, reinforced components. At least some known wind turbines, when subjected to cold weather conditions with ambient air temperature values below the lower temperature limit of the allowable temperature range, are shut off, which is disadvantageous insofar as no electric output power is generated.

Another example of seasonal changes affecting wind turbine performance is that air temperature-corrected turbine performance of at least some known wind turbines may be lower in the summer than in the winter. For example, a probability of the rotor blades of at least some known wind turbines to stall increases during summer conditions when ambient air temperatures are typically higher. Such stalling reduces a potential electric power output of the wind turbine. Moreover, reestablishment of airflow around at least some known wind turbine rotor blades after stalling may cause a short-term increase in generator speed and/or electric power output that may be difficult for a controller of the wind turbine to process. Such controller processing difficulty may increase a probability of the wind turbine to be disconnected from an electric grid due to over-speed and/or over-production conditions.

BRIEF DESCRIPTION OF THE INVENTION

In one aspect, a method for operating a wind turbine. The method includes measuring an ambient air temperature and decreasing a power output of the wind turbine if the measured ambient air temperature is below a predetermined limit to thereby facilitate reducing loads acting on components of the wind turbine.

In another aspect, a wind turbine is provided. The wind turbine includes a rotor that includes a hub and at least one rotor blade coupled to the hub. The wind turbine also includes a first sensor configured to measure ambient air temperature and generate and transmit an ambient air temperature signal. The wind turbine further includes at least one processor coupled in electronic data communication to the first sensor. The at least one processor is configured to facilitate reducing loads acting on components of the wind turbine by at least one of receiving a measured ambient air temperature signal from the first sensor and decreasing a power output of the wind turbine if the received ambient air temperature signal is below a predetermined limit.

In a further aspect, a method for operating a wind turbine having at least one blade is provided. The method includes determining an ambient air operating envelope and controlling a power output of the wind turbine at least partially based on the determined ambient air operating envelope.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of an exemplary wind turbine;

FIG. 2 is a schematic view of an exemplary nacelle that may be used with the wind turbine shown in FIG. 1 ;

FIG. 3 is an electrical and electronic schematic diagram of the wind turbine shown in FIG. 1 ;

FIG. 4 is a flowchart illustrating an exemplary method for controlling the wind turbine shown in FIG. 1 ; and

FIG. 5 is a flowchart illustrating another exemplary method for controlling the wind turbine shown in FIG. 1 .

DETAILED DESCRIPTION OF THE INVENTION

As used herein, the term “blade” is intended to be representative of any device that provides reactive force when in motion relative to a surrounding fluid. As used herein, the term “wind turbine” is intended to be representative of any device that generates rotational energy from wind energy, and more specifically, converts kinetic energy of wind into mechanical energy. As used herein, the term “wind turbine generator” is intended to be representative of any wind turbine that generates electrical power from rotational energy generated from wind energy, and more specifically, converts mechanical energy converted from kinetic energy of wind to electrical power. As used herein, the term “windmill” is intended to be representative of any wind turbine that uses rotational energy generated from wind energy, and more specifically mechanical energy converted from kinetic energy of wind, for a predetermined purpose other than generating electrical power, such as, but not limited to, pumping a fluid and/or grinding a substance.

FIG. 1 is a schematic view an exemplary wind turbine 10 . FIG. 2 is a schematic view of an exemplary nacelle 16 that may be used with wind turbine 10 (shown in FIG. 1 ). FIG. 3 is an electrical and electronic schematic diagram of wind turbine 10 (shown in FIG. 1 ). Wind turbine 10 described and illustrated herein is a wind generator for generating electrical power from wind energy. However, in some embodiments, wind turbine 10 may be, in addition or alternative to a wind generator, any type of wind turbine, such as, but not limited to, a windmill (not shown). Moreover, wind turbine 10 described and illustrated herein includes a horizontal-axis configuration. However, in some embodiments, wind turbine 10 may include, in addition or alternative to the horizontal-axis configuration, a vertical-axis configuration (not shown). Wind turbine 10 may be coupled to an electrical load (not shown), such as, but not limited to, a power grid (not shown), for receiving electrical power therefrom to drive operation of wind turbine 10 and/or its associated components and/or for supplying electrical power generated by wind turbine 10 thereto. Although only one wind turbine 10 is shown in FIG. 1-3 , in some embodiments a plurality of wind turbines 10 may be grouped together, sometimes referred to as a “wind farm”.

Wind turbine 10 includes a body 16 , sometimes referred to as a “nacelle”, and a rotor (generally designated by 18 ) coupled to body 16 for rotation with respect to body 16 about an axis of rotation 20 . In the exemplary embodiment, nacelle 16 is mounted on a tower 14 . However, in some embodiments, in addition or alternative to tower-mounted nacelle 16 , wind turbine 10 includes a nacelle 16 adjacent the ground and/or a surface of water. The height of tower 14 may be any suitable height enabling wind turbine 10 to function as described herein. Rotor 18 includes a hub 22 and a plurality of blades 24 (sometimes referred to as “airfoils”) extending radially outwardly from hub 22 for converting wind energy into rotational energy. Although rotor 18 is described and illustrated herein as having three blades 24 , rotor 18 may have any number of blades 24 . Blades 24 may each have any length (whether described herein). For example, in some embodiments one or more rotor blades 24 are about 0.5 meters (m) (1.64 feet (ft)) long, while in some embodiments one or more rotor blades 24 are about 50 m (164 ft) long. Other examples of blade 24 lengths include 10 m (32.8 ft) or less, about 20 m (65.6 ft), about 37 m (121.4 ft), and about 40 m (131.2 ft). Still other examples include rotor blades between about 50 and about 100 meters long (164 ft to 328 ft).

Despite how rotor blades 24 are illustrated in FIG. 1 , rotor 18 may have blades 24 of any shape, and may have blades 24 of any type and/or any configuration, whether such shape, type, and/or configuration is described and/or illustrated herein. One example of another type, shape, and/or configuration of rotor blades 24 is a ducted rotor (not shown) having a turbine (not shown) contained within a duct (not shown). Another example of another type, shape, and/or configuration of rotor blades 24 is a darrieus wind turbine, sometimes referred to as an “eggbeater” turbine. Yet another example of another type, shape, and/or configuration of rotor blades 24 is a savonious wind turbine. Even another example of another type, shape, and/or configuration of rotor blades 24 is a traditional windmill for pumping water, such as, but not limited to, four-bladed rotors having wooden shutters and/or fabric sails. Moreover, wind turbine 10 may, in some embodiments, be a wind turbine wherein rotor 18 generally faces upwind to harness wind energy, and/or may be a wind turbine wherein rotor 18 generally faces downwind to harness energy. Of course, in any embodiments, rotor 18 may not face exactly upwind and/or downwind, but may face generally at any angle (which may be variable) with respect to a direction of the wind to harness energy therefrom.

Referring now to FIGS. 2 and 3 , wind turbine 10 includes an electrical generator 26 coupled to rotor 18 for generating electrical power from the rotational energy generated by rotor 18 . In the exemplary embodiment, generator 26 is a round rotor, synchronous, three-phase, permanent magnet generator that includes a generator rotor 25 and a stator 27 . However, generator 26 may be any type of generator including, but not limited to, salient pole generators, double-sided stator generators, and/or doubly-fed induction generators. In the exemplary embodiment, generator rotor 25 includes a plurality of permanent magnets 29 that are coupled to generator rotor 25 . Alternatively, generator rotor 25 may be a wound rotor wherein the associated windings (neither shown) are separately-excited, for example, but not limited to, a salient-pole rotor. Generator rotor 25 and stator 27 are positioned such that a clearance gap 31 (sometimes referred to as an air gap) is defined between stator 27 and generator rotor 25 with a predetermined clearance gap radial dimension (not shown). Permanent magnets 29 with predetermined polarities are positioned to generate a magnetic field (not shown) around generator rotor 25 with a predetermined number of poles and a predetermined magnetic strength.

Stator 27 includes a plurality of stator windings (not shown). Gap 31 facilitates magnetic coupling of generator rotor 25 and stator 27 to generate a predetermined voltage within stator 27 at a predetermined frequency that is determined by generator rotor 25 rotational speed as generator rotor 25 is rotated within stator 27 . The generated voltages within stator 27 subsequently generate a predetermined electric current within stator 27 . The electric currents generated within stator 27 subsequently generate a plurality of magnetic fields and as the magnetic field generated in generator rotor 25 rotates, the magnetic field of generator rotor 25 interacts with the magnetic fields of stator 27 through gap 31 . The interaction of the magnetic fields induces magnetomotive axial and radial forces and a torque that act on generator rotor 25 . The radial and axial forces and torque induced on generator rotor 25 by the interaction of the magnetic fields are proportional to the strength and position of the magnetic flux component within gap 31 . As the flux component in gap 31 increases, the radial and axial forces and torque induced on generator rotor 25 increase. Similarly, as the flux component in gap 31 decreases, the radial and axial forces and torque induced on generator rotor 25 decrease. Therefore, modulating the flux modulates the radial and axial forces and torque induced on generator rotor 25 .

Rotor 18 includes a rotor shaft 30 coupled to rotor hub 22 for rotation therewith. Generator 26 is coupled to rotor shaft 30 such that rotation of rotor shaft 30 drives rotation of generator rotor 25 , and therefore facilitates operation of generator 26 . In the exemplary embodiment, generator rotor 25 includes a rotor shaft 28 rotatingly coupled thereto and rotatingly coupled to rotor shaft 30 such that rotation of rotor shaft 30 drives rotation of generator rotor 25 . In other embodiments, generator rotor 25 is directly rotatably coupled to rotor shaft 30 , sometimes referred to as a “direct-drive wind turbine”. In the exemplary embodiment, generator rotor shaft 28 is rotatably coupled to rotor shaft 30 through a gearbox 32 , although in other embodiments generator rotor shaft 28 is rotatably coupled directly to rotor shaft 30 . More specifically, in the exemplary embodiment gearbox 32 has a low speed side 34 rotatably coupled to rotor shaft 30 and a high speed side 36 rotatably coupled to generator rotor shaft 28 . The torque of rotor 18 drives generator rotor 25 to thereby generate variable frequency AC electrical power from rotation of rotor 18 . A frequency converter 38 is electrically coupled to generator 26 for converting the variable frequency AC to a fixed frequency AC for delivery to an electrical utility grid 39 . Frequency converter 38 may be located anywhere within or remote to wind turbine 10 . For example, in the exemplary embodiment, frequency converter 38 is located within a base (not shown) of tower 14 .

In some embodiments, wind turbine 10 may include at least one control system 40 coupled to at least one of the components of wind turbine 10 for generally controlling operation of wind turbine 10 and/or as some or all of the components thereof (whether such components are described and/or illustrated herein). In the exemplary embodiment, control system 40 is mounted within nacelle 16 . However, additionally or alternatively, control system 40 may be remote from nacelle 16 and/or other components of wind turbine 10 . Control system 40 may be used for, but is not limited to, overall system monitoring and control including, for example, pitch and speed regulation, high-speed shaft and yaw brake application, yaw and pump motor application, and/or fault monitoring. Alternative distributed or centralized control architectures may be used in some embodiments.

In some embodiments, wind turbine 10 may include a disc brake (not shown) for braking rotation of rotor 18 to, for example, slow rotation of rotor 18 , brake rotor 18 against full wind torque, and/or reduce the generation of electrical power from electrical generator 26 . Furthermore, in some embodiments, wind turbine 10 may include a yaw system 42 for rotating nacelle 16 about an axis of rotation 44 for changing a yaw of rotor 18 , and more specifically for changing a direction faced by rotor 18 to, for example, adjust an angle between the direction faced by rotor 18 and a direction of wind. Yaw system 42 may be coupled in electronic data communication to control system 40 for control thereby.

In some embodiments, wind turbine 10 may include anemometry 46 for measuring wind speed and/or wind direction. Anemometry 46 , in some embodiments, may be coupled in electronic data communication to control system 40 for sending measurements to control system 40 for processing thereof. For example, and although anemometry 46 may be coupled in electronic data communication to control system 40 for sending measurements thereto for controlling other operations of wind turbine 10 , anemometry 46 may send measurements to control system 40 for controlling and/or changing a yaw of rotor 18 using yaw system 42 . Alternatively, anemometry 46 may be coupled in electronic data communication directly to yaw system 42 for controlling and/or changing a yaw of rotor 18 .

Wind turbine 10 may also include a plurality of sensors 48 , each coupled to a corresponding blade 24 for measuring a pitch of each blade 24 , or more specifically an angle of each blade 24 with respect to a wind direction and/or with respect to rotor hub 22 . Sensors 48 may be any suitable sensor having any suitable location within or remote to wind turbine 10 , such as, but not limited to, optical encoders within pitch system 62 (described below). In some embodiments, sensors 48 are coupled in electronic data communication to control system 40 for sending pitch measurements to control system 40 for processing thereof.

In some embodiments, wind turbine 10 includes at least one sensor 50 coupled to rotor shaft 30 for measuring a speed of rotation of rotor shaft 30 and/or a torque of rotor shaft 30 . Sensor 50 may be any suitable sensor having any suitable location within or remote to wind turbine 10 , such as, but not limited to, optical encoders, digital proximity sensors, piezo-electric transducers, strain gages, and/or tachometers. In some embodiments, sensor 50 is coupled in electronic data communication to control system 40 for sending measurements to control system 40 for processing thereof. Furthermore, in some embodiments, wind turbine 10 includes at least one sensor 52 coupled to generator 26 for measuring an electrical power output of generator 26 . In some embodiments, sensor 52 is coupled in electronic data communication to control system 40 for sending measurements to control system 40 for processing thereof. Sensor 52 may be any suitable sensor having any suitable location within or remote to wind turbine 10 , such as, but not limited to, Hall effect current transducers (CTs) and/or capacitive voltage transducers (CVTs).

In some embodiments, wind turbine 10 includes at least one sensor 54 configured to measure ambient air pressure. Sensor 54 may be any suitable sensor having any suitable location within or remote to wind turbine 10 , such as, but not limited to, electric barometric pressure measurement instruments. In some embodiments, sensor 54 is coupled in electronic data communication to control system 40 for sending ambient air pressure measurement signals to control system 40 for processing thereof.

In some embodiments, wind turbine 10 includes at least one sensor 56 configured to measure ambient air temperature. Sensor 56 may be any suitable sensor having any suitable location within or remote to wind turbine 10 , such as, but not limited to, electronic thermometers. In some embodiments, sensor 56 is coupled in electronic data communication to control system 40 for sending ambient air temperature measurements to control system 40 for processing thereof.

In some embodiments, wind turbine 10 includes at least one sensor 58 configured to measure the flux generated within gap 31 and/or the torque induced on generator rotor 25 . Sensor 58 may be any suitable sensor having any suitable location within generator 26 , such as, but not limited to, flux measurement assemblies and/or torque measurement assemblies. In some embodiments, sensor 58 is coupled in electronic data communication to control system 40 for sending gap flux and/or generator rotor torque measurements to control system 40 for processing thereof.

In some embodiments, wind turbine 10 includes at least one sensor 60 configured to measure ambient air humidity. Sensor 60 may be any suitable sensor having any suitable location within or remote to wind turbine 10 , such as, but not limited to, electronic relative humidity sensors. In some embodiments, sensor 60 is coupled in electronic data communication to control system 40 for sending ambient air humidity measurements to control system 40 for processing thereof.

Wind turbine 10 may also include one or more other sensors (not shown) coupled to one or more components of wind turbine 10 and/or the electrical load, whether such component(s) are described or illustrated herein, for measuring parameters of such component(s) and/or for measuring other ambient conditions. Such other sensor(s) may include, but are not limited to, sensors configured to measure any ambient condition, any operational parameter of any wind turbine component, displacement, yaw, pitch, moments, strain, stress, twist, damage, failure, rotor torque, rotor speed, an anomaly in the electrical load, and/or an anomaly of power supplied to any component of wind turbine 10 . Such other sensors may couple to any component of wind turbine 10 and/or the electrical load at any location thereof for measuring any parameter thereof, whether such component, location, and/or parameter is described and/or illustrated herein, and may be used to derive other measurements, e.g., viscosity, as known in the art.

Wind turbine 10 includes a variable blade pitch system 62 for controlling, including but not limited to changing, a pitch angle of rotor blades 24 with respect to a wind direction. Pitch system 62 may be coupled to control system 40 for control thereby. Pitch system 62 includes one or more actuators (not shown) coupled to hub 22 and blades 24 for changing the pitch angle of blades 24 by rotating blades 24 with respect to hub 22 . The pitch actuators may include any suitable structure, configuration, arrangement, means, and/or components, whether described an

CLAIMS

Claims ( 5 )

What is claimed is:

1. A method for operating a wind turbine having at least one blade, said method comprising:

determining an ambient air operating envelope comprises:

measuring at least one of an ambient air temperature, an ambient air pressure, an ambient air humidity, and wind turbine power output;

comparing at least one of the measured ambient air temperature, measured ambient air humidity and measured ambient air pressure to a predetermined ambient air temperature, predetermined ambient air pressure and predetermined ambient air humidity values; and

referencing the predetermined ambient air temperature, predetermined ambient air pressure and predetermined ambient air humidity values to at least one of a predetermined range of blade rotational speeds and a predetermined range of wind turbine power outputs; and

controlling a power output of the wind turbine at least partially based on the determined ambient air operating envelope.

2. A method in accordance with claim 1 further comprising determining if an existing wind turbine power output is within a range associated with the determined ambient air operating envelope.

3. A method in accordance with claim 1 wherein controlling a power output of the wind turbine comprises at least one of: controlling a pitch angle of at least one rotor blade of the wind turbine at least partially based on the ambient air operating envelope; and controlling a torque of a generator rotor of the wind turbine at least partially based on the ambient air operating envelope.

4. A method in accordance with claim 1 wherein the wind turbine is configured to withstand loads acting on the wind turbine within at least one of a predetermined ambient air temperature range, a predetermined ambient air pressure range and a predetermined ambient air humidity range, wherein each of the predetermined ambient air temperature, predetermined ambient air pressure and predetermined ambient air humidity ranges have lower and upper limits referenced to at least one of predetermined wind speed parameters and predetermined wind turbine power outputs, and wherein controlling the power output of the wind turbine at least partially based on the determined ambient air operating envelope comprises decreasing the power output of the wind turbine to facilitate withstanding loads acting thereon.

5. A method in accordance with claim 1 wherein the wind turbine is configured to mitigate stalling of the wind turbine within at least one of a predetermined ambient air temperature range, a predetermined ambient air pressure range and a predetermined ambient air humidity range, wherein each of the predetermined ambient air temperature, predetermined ambient air pressure and predetermined ambient air humidity ranges have lower and upper limits referenced to at least one of predetermined wind speed parameters and predetermined wind turbine power outputs, and wherein controlling a the power output of the wind turbine at least partially based on the determined ambient air operating envelope comprises decreasing the power output of the wind turbine to facilitate mitigating a potential for stalling thereon.

US13/720,441

2006-10-23

2012-12-19

Methods for operating a wind turbine

Active

US8738192B2

( en )

Priority Applications (1)

Application Number

Priority Date

Filing Date

Title

US13/720,441

US8738192B2

( en )

2006-10-23

2012-12-19

Methods for operating a wind turbine

Applications Claiming Priority (2)

Application Number

Priority Date

Filing Date

Title

US11/551,884

US20080112807A1

( en )

2006-10-23

2006-10-23

Methods and apparatus for operating a wind turbine

US13/720,441

US8738192B2

( en )

2006-10-23

2012-12-19

Methods for operating a wind turbine

Related Parent Applications (1)

Application Number

Title

Priority Date

Filing Date

US11/551,884

Division

US20080112807A1

( en )

2006-10-23

2006-10-23

Methods and apparatus for operating a wind turbine

Publications (2)

Publication Number

Publication Date

US20130108443A1

US20130108443A1 ( en )

2013-05-02

US8738192B2

true

US8738192B2 ( en )

2014-05-27

Family

ID=39156248

Family Applications (2)

Application Number

Title

Priority Date

Filing Date

US11/551,884

Abandoned

US20080112807A1

( en )

2006-10-23

2006-10-23

Methods and apparatus for operating a wind turbine

US13/720,441

Active

US8738192B2

( en )

2006-10-23

2012-12-19

Methods for operating a wind turbine

Family Applications Before (1)

Application Number

Title

Priority Date

Filing Date

US11/551,884

Abandoned

US20080112807A1

( en )

2006-10-23

2006-10-23

Methods and apparatus for operating a wind turbine

Country Status (5)

Country

Link

US

( 2 )

US20080112807A1

( en )

EP

( 1 )

EP1918581B1

( en )

CN

( 1 )

CN101169103B

( en )

DK

( 1 )

DK1918581T3

( en )

ES

( 1 )

ES2880615T3

( en )

Cited By (8)

* Cited by examiner, † Cited by third party

Publication number

Priority date

Publication date

Assignee

Title

US20120299298A1

( en )

*

2011-05-24

2012-11-29

Gamesa Innovation &amp; Technology, S.L.

Wind turbine control methods and systems for cold climate and low altitude conditions

US20140056706A1

( en )

*

2012-08-24

2014-02-27

Hans Laurberg

Operating a wind turbine with multiple temperature sensors

US20140248123A1

( en )

*

2011-09-30

2014-09-04

Vestas Wind Systems A/S

Control of wind turbines

US20160348646A1

( en )

*

2015-05-26

2016-12-01

General Electric Company

System and method for de-rating power of a wind turbine as a function of temperature

US10400753B2

( en )

2014-04-09

2019-09-03

Wobben Properties Gmbh

Method for feeding in electrical energy by means of a wind turbine

US20210388816A1

( en )

*

2018-10-10

2021-12-16

Siemens Gamesa Renewable Energy Service Gmbh

Method and assembly for accessing scada data of wind turbines

US20220291649A1

( en )

*

2019-08-14

2022-09-15

Siemens Gamesa Renewable Energy A/S

Method for computer-implemented determination of control parameters of a turbine

US11542921B2

( en )

*

2017-06-16

2023-01-03

Vestas Wind Systems A/S

Apparatus and methods for monitoring the ambient environment of wind turbines

Families Citing this family (76)

* Cited by examiner, † Cited by third party

Publication number

Priority date

Publication date

Assignee

Title

AU2008313747A1

( en )

*

2007-10-15

2009-04-23

Suzlon Energy Gmbh

Wind energy installation with enhanced overvoltage protection

US8736092B2

( en )

*

2008-03-07

2014-05-27

Vestas Wind Systems A/S

Control system and a method for redundant control of a wind turbine

US8474255B2

( en )

2008-04-09

2013-07-02

Sustainx, Inc.

Forming liquid sprays in compressed-gas energy storage systems for effective heat exchange

US8037678B2

( en )

2009-09-11

2011-10-18

Sustainx, Inc.

Energy storage and generation systems and methods using coupled cylinder assemblies

US8448433B2

( en )

2008-04-09

2013-05-28

Sustainx, Inc.

Systems and methods for energy storage and recovery using gas expansion and compression

US8479505B2

( en )

2008-04-09

2013-07-09

Sustainx, Inc.

Systems and methods for reducing dead volume in compressed-gas energy storage systems

WO2009126784A2

( en )

2008-04-09

2009-10-15

Sustainx, Inc.

Systems and methods for energy storage and recovery using compressed gas

US7958731B2

( en )

2009-01-20

2011-06-14

Sustainx, Inc.

Systems and methods for combined thermal and compressed gas energy conversion systems

US8359856B2

( en )

2008-04-09

2013-01-29

Sustainx Inc.

Systems and methods for efficient pumping of high-pressure fluids for energy storage and recovery

US8250863B2

( en )

2008-04-09

2012-08-28

Sustainx, Inc.

Heat exchange with compressed gas in energy-storage systems

US7802426B2

( en )

2008-06-09

2010-09-28

Sustainx, Inc.

System and method for rapid isothermal gas expansion and compression for energy storage

US8240140B2

( en )

2008-04-09

2012-08-14

Sustainx, Inc.

High-efficiency energy-conversion based on fluid expansion and compression

US8677744B2

( en )

2008-04-09

2014-03-25

SustaioX, Inc.

Fluid circulation in energy storage and recovery systems

US20100307156A1

( en )

2009-06-04

2010-12-09

Bollinger Benjamin R

Systems and Methods for Improving Drivetrain Efficiency for Compressed Gas Energy Storage and Recovery Systems

US8225606B2

( en )

2008-04-09

2012-07-24

Sustainx, Inc.

Systems and methods for energy storage and recovery using rapid isothermal gas expansion and compression

NZ590221A

( en )

*

2008-06-30

2013-05-31

Vestas Wind Sys As

Controlling instantaneous power output from a wind power plant based on a determined upper limit power output

GB2461711A

( en )

*

2008-07-08

2010-01-13

Cypress Wind Turbines Oy

Vertical axis wind turbine with direct-drive coupling between shaft and generator

US8108155B2

( en )

*

2008-07-11

2012-01-31

Vestas Wind Systems A/S

System for monitoring a restoration factor of a wind turbine population

US8109711B2

( en )

2008-07-18

2012-02-07

Honeywell International Inc.

Tethered autonomous air vehicle with wind turbines

US7946814B2

( en )

*

2008-08-29

2011-05-24

General Electric Company

Wind turbine blade cleaning method

US20100090463A1

( en )

*

2008-10-10

2010-04-15

Jacob Johannes Nies

Combined environmental monitoring and power supply device

US7963110B2

( en )

2009-03-12

2011-06-21

Sustainx, Inc.

Systems and methods for improving drivetrain efficiency for compressed gas energy storage

AT508242B1

( en )

*

2009-04-10

2015-05-15

Andritz Hydro Gmbh

ENERGY INJECTION INTO A CURRENT NETWORK

EP2264314B1

( en )

*

2009-05-25

2016-05-25

Vestas Wind Systems A/S

A method and a system for controlling operation of a wind turbine

US7780412B2

( en )

*

2009-05-28

2010-08-24

General Electric Company

Operating a wind turbine at motor over-temperature conditions

US8104274B2

( en )

2009-06-04

2012-01-31

Sustainx, Inc.

Increased power in compressed-gas energy storage and recovery

CN101981310B

( en )

*

2009-06-05

2013-10-30

三菱重工业株式会社

Wind power generation device, control method thereof, and wind power generation system

US20100326343A1

( en )

*

2009-06-30

2010-12-30

Hunt Turner

Mooring system for a tethered hydrokinetic device and an array thereof

US7948103B2

( en )

*

2009-09-03

2011-05-24

General Electric Company

Method and system for verifying wind turbine operation

US8328514B2

( en )

*

2009-09-11

2012-12-11

General Electric Company

System and methods for determining a monitor set point limit for a wind turbine

US8295986B2

( en )

*

2009-09-28

2012-10-23

Chandramouli Vaidyanathan

Net metering apparatus for power generation systems

US8215907B2

( en )

*

2009-09-30

2012-07-10

General Electric Company

Method and apparatus for controlling acoustic emissions of a wind turbine

ATE546646T1

( en )

2009-10-06

2012-03-15

Siemens Ag

METHOD FOR CONTROLLING A WIND TURBINE IN THE EVENT OF THERMAL OVERLOADS

US20100135790A1

( en )

*

2009-10-14

2010-06-03

Sujan Kumar Pal

Wind turbine blade with foreign matter detection devices

US7880320B2

( en )

2009-10-30

2011-02-01

General Electric Company

System, device, and method for controlling a wind turbine using seasonal parameters

US8118536B2

( en )

*

2009-10-30

2012-02-21

General Electric Company

Method and system for operating a wind turbine

WO2011056855A1

( en )

2009-11-03

2011-05-12

Sustainx, Inc.

Systems and methods for compressed-gas energy storage using coupled cylinder assemblies

US8120194B2

( en )

*

2010-03-05

2012-02-21

General Electric Company

System, device, and method for wind turbine load reduction in a cold weather environment

US8171728B2

( en )

2010-04-08

2012-05-08

Sustainx, Inc.

High-efficiency liquid heat exchange in compressed-gas energy storage systems

US8191362B2

( en )

2010-04-08

2012-06-05

Sustainx, Inc.

Systems and methods for reducing dead volume in compressed-gas energy storage systems

US8234863B2

( en )

2010-05-14

2012-08-07

Sustainx, Inc.

Forming liquid sprays in compressed-gas energy storage systems for effective heat exchange

US8222760B2

( en )

*

2010-06-29

2012-07-17

General Electric Company

Method for controlling a proximity sensor of a wind turbine

US8495872B2

( en )

2010-08-20

2013-07-30

Sustainx, Inc.

Energy storage and recovery utilizing low-pressure thermal conditioning for heat exchange with high-pressure gas

CN103154509B

( en )

2010-08-23

2016-03-16

维斯塔斯风力系统集团公司

Method of operating a wind turbine and wind turbine

US8578708B2

( en )

2010-11-30

2013-11-12

Sustainx, Inc.

Fluid-flow control in energy storage and recovery systems

DE102010054014A1

( en )

2010-12-10

2012-06-14

Nordex Energy Gmbh

Method for operating a pitch-controlled wind turbine

DE102010054013A1

( en )

2010-12-10

2012-06-14

Nordex Energy Gmbh

Method for operating a pitch-controlled wind turbine

EP2679811B1

( en )

2011-02-23

2017-10-04

Mitsubishi Heavy Industries, Ltd.

Control device for wind turbine device, wind turbine device, and method for controlling wind turbine device

WO2012129721A1

( en )

*

2011-03-29

2012-10-04

General Electric Company

Method for adjusting power output of wind turbine

EP2712402B1

( en )

*

2011-05-06

2020-12-23

Seawind Ocean Technology Holding BV

Systems for minimizing the yaw torque needed to control power output by yawing , for wind turbines with two hinged teetering blades.

EP2715075A2

( en )

2011-05-17

2014-04-09

Sustainx, Inc.

Systems and methods for efficient two-phase heat transfer in compressed-air energy storage systems

DE102011101897A1

( en )

2011-05-18

2012-11-22

Nordex Energy Gmbh

Method for operating a wind energy plant

US20120025528A1

( en )

*

2011-05-20

2012-02-02

General Electric Company

Magnetostrictive sensor system and method

US20130091834A1

( en )

2011-10-14

2013-04-18

Sustainx, Inc.

Dead-volume management in compressed-gas energy storage and recovery systems

EP2610484A1

( en )

*

2011-12-26

2013-07-03

Vestas Wind Systems A/S

Method for controlling a wind turbine

US20130259682A1

( en )

*

2012-03-27

2013-10-03

General Electric Company

Method of rotor-stall prevention in wind turbines

CA2871946C

( en )

2012-05-04

2015-10-20

Wind Energy Corporation

Wind turbine system and method of operating a wind turbine system

CN104564529B

( en )

*

2014-12-30

2017-07-14

北京金风科创风电设备有限公司

Output power compensation method, device and system of wind generating set

DE102016110190A1

( en )

2016-06-02

2017-12-07

Wobben Properties Gmbh

Method for controlling a wind turbine and wind turbine

DE102016124703A1

( en )

2016-12-16

2018-06-21

Wobben Properties Gmbh

A method of operating a wind turbine and means for controlling and / or regulating a wind turbine and corresponding wind turbine with a rotor and a generator driven via the rotor for generating an electrical power

DE102016125375A1

( en )

*

2016-12-22

2018-06-28

Innogy Se

TRANSMISSION STATION, METHOD AND DEVICE FOR A TRANSMISSION STATION

EP3343025A1

( en )

*

2016-12-30

2018-07-04

Acciona Windpower, S.A.

Method of reducing loads acting on a wind turbine yaw system

EP3638902B1

( en )

*

2017-06-16

2021-04-21

Vestas Wind Systems A/S

Apparatus and methods for determining icing risk in wind turbines

WO2019042751A1

( en )

*

2017-08-28

2019-03-07

Siemens Gamesa Renewable Energy A/S

Bearing protection arrangement

US10669988B2

( en )

*

2017-10-10

2020-06-02

General Electric Company

System and method for operating wind turbines to avoid stall during derating

CN108425801A

( en )

*

2018-02-13

2018-08-21

梁瑞城

A kind of model wind generating device with real time temperature monitoring function

DE102018113531A1

( en )

2018-06-06

2019-12-12

Wobben Properties Gmbh

A method of operating a wind turbine and means for controlling and / or regulating a wind turbine and wind turbine with a rotor and a generator driven via the rotor

US11261845B2

( en )

*

2018-07-26

2022-03-01

General Electric Company

System and method for protecting wind turbines during extreme wind direction change

CN109372690B

( en )

*

2018-12-29

2022-12-13

新疆金风科技股份有限公司

Power control method, device, electronic equipment and medium of wind power generating set

CN113027696B

( en )

*

2019-12-24

2022-11-15

新疆金风科技股份有限公司

Fault diagnosis method and device of hydraulic variable pitch system

EP3869031B1

( en )

*

2020-02-21

2022-09-28

Siemens Gamesa Renewable Energy A/S

Method of controlling a blade pitch angle of a wind turbine by use of a hydraulic system

CN114439681B

( en )

*

2020-10-30

2024-12-10

金风科技股份有限公司

Power boosting method and device for wind turbine generator set

EP3995691B1

( en )

2020-11-04

2026-04-29

Wobben Properties GmbH

Methods for operating a wind turbine

US11536250B1

( en )

*

2021-08-16

2022-12-27

General Electric Company

System and method for controlling a wind turbine

CN113432658B

( en )

*

2021-08-26

2022-01-11

广东信通通信有限公司

A risk prediction and evaluation system for electric power operation

CN115783276B

( en )

*

2023-02-02

2023-04-11

江苏新扬新材料股份有限公司

Temperature compensation device of airplane propeller speed regulator

Citations (32)

* Cited by examiner, † Cited by third party

Publication number

Priority date

Publication date

Assignee

Title

US3671814A

( en )

1970-04-22

1972-06-20

Voith Getriebe Kg

Electromagnet with a field-responsive control system

US4193005A

( en )

1978-08-17

1980-03-11

United Technologies Corporation

Multi-mode control system for wind turbines

US4245181A

( en )

1979-02-26

1981-01-13

General Electric Company

Method and apparatus for generating an air gap flux signal for an AC machine from AC line voltage and current values

US4339666A

( en )

1980-12-24

1982-07-13

United Technologies Corporation

Blade pitch angle control for a wind turbine generator

US4345198A

( en )

1981-02-20

1982-08-17

General Electric Company

Generator air gap electrical torque monitor

US5083039A

( en )

1991-02-01

1992-01-21

U.S. Windpower, Inc.

Variable speed wind turbine

US5761086A

( en )

*

1996-02-13

1998-06-02

Westinghouse Electric Corporation

Apparatus and method for monitoring pressure-temperature margins

US6057622A

( en )

1999-01-21

2000-05-02

Lockhead Martin Energy Research Corporation

Direct control of air gap flux in permanent magnet machines

US6361275B1

( en )

1997-07-25

2002-03-26

Aloys Wobben

Wind energy installation

US6525504B1

( en )

1997-11-28

2003-02-25

Abb Ab

Method and device for controlling the magnetic flux in a rotating high voltage electric alternating current machine

US6600240B2

( en )

1997-08-08

2003-07-29

General Electric Company

Variable speed wind turbine generator

US6703718B2

( en )

2001-10-12

2004-03-09

David Gregory Calley

Wind turbine controller

US20040135375A1

( en )

2001-02-28

2004-07-15

Aloys Wobben

Atmospheric density-dependent power adjustment for wind turbines

US6809431B1

( en )

1998-09-26

2004-10-26

Dewind Ag

Control logic for a wind energy system

US20060002791A1

( en )

2004-06-30

2006-01-05

Moroz Emilian M

Methods and apparatus for reducing peak wind turbine loads

US7011498B2

( en )

1998-04-03

2006-03-14

Athena Technologies, Inc.

Optimization method for power generation systems

CN1833103A

( en )

2003-09-10

2006-09-13

三菱重工业株式会社

Blade pitch angle control device and wind power generation device

CN1873219A

( en )

2005-06-03

2006-12-06

通用电气公司

System and method for operating a wind farm under high wind speed conditions

US20070018457A1

( en )

2005-07-22

2007-01-25

Gamesa Eolica, S.A.

Method of operating a wind turbine

US20070041837A1

( en )

2003-09-10

2007-02-22

Mitsubishi Heavy Industries, Ltd.

Blade-pitch-angle control device and wind power generator

US20070216166A1

( en )

2004-09-21

2007-09-20

Repower Systems Ag

Method for controlling a wind power plant and corresponding wind power plant

EP2067989A2

( en )

2007-12-06

2009-06-10

General Electric Company

System and method for controlling a wind power plant

US20100133827A1

( en )

2009-09-30

2010-06-03

Xiongzhe Huang

Method and system for controlling a wind turbine

US7794209B2

( en )

2004-02-13

2010-09-14

Aloys Wobben

Rotor blade for a wind turbine

US20100274400A1

( en )

2009-04-22

2010-10-28

Vestas Wind Systems A/S

Wind turbine configuration system

US7857586B2

( en )

*

2003-05-23

2010-12-28

Aloys Wobben

Method for operating a wind turbine

US7942634B2

( en )

*

2007-07-14

2011-05-17

Vestas Wind Systems A/S

Wind turbine, a method for compensating for disparities in a wind turbine rotor blade pitch system and use of a method

US8057174B2

( en )

*

2008-10-09

2011-11-15

General Electric Company

Method for controlling a wind turbine using a wind flow model

US20110309621A1

( en )

2008-11-18

2011-12-22

Thomas Steiniche Bjertrup Nielsen

Method for controlling operation of a wind turbine

US8183707B2

( en )

2007-10-30

2012-05-22

General Electric Company

Method of controlling a wind energy system and wind speed sensor free wind energy system

US8239071B2

( en )

*

2007-08-31

2012-08-07

Vestas Wind Systems A/S

Method for controlling at least one adjustment mechanism of a wind turbine, a wind turbine and a wind park

US8328514B2

( en )

*

2009-09-11

2012-12-11

General Electric Company

System and methods for determining a monitor set point limit for a wind turbine

2006

2006-10-23

US

US11/551,884

patent/US20080112807A1/en

not_active

Abandoned

2007

2007-10-17

EP

EP07118641.5A

patent/EP1918581B1/en

active

Active

2007-10-17

DK

DK07118641.5T

patent/DK1918581T3/en

active

2007-10-17

ES

ES07118641T

patent/ES2880615T3/en

active

Active

2007-10-23

CN

CN200710182379.2A

patent/CN101169103B/en

active

Active

2012

2012-12-19

US

US13/720,441

patent/US8738192B2/en

active

Active

Patent Citations (38)

* Cited by examiner, † Cited by third party

Publication number

Priority date

Publication date

Assignee

Title

US3671814A

( en )

1970-04-22

1972-06-20

Voith Getriebe Kg

Electromagnet with a field-responsive control system

US4193005A

( en )

1978-08-17

1980-03-11

United Technologies Corporation

Multi-mode control system for wind turbines

US4245181A

( en )

1979-02-26

1981-01-13

General Electric Company

Method and apparatus for generating an air gap flux signal for an AC machine from AC line voltage and current values

US4339666A

( en )

1980-12-24

1982-07-13

United Technologies Corporation

Blade pitch angle control for a wind turbine generator

US4345198A

( en )

1981-02-20

1982-08-17

General Electric Company

Generator air gap electrical torque monitor

US5083039B1

( en )

1991-02-01

1999-11-16

Zond Energy Systems Inc

Variable speed wind turbine

US5225712A

( en )

<td itempro

Related documents

• Generating augmented reality experiences utilizing physical objects to … — Meta Platforms Technologies, Llc (US20260037214A1)#653960
• Virtual reality system using multiple force arrays for a solver — DeepMotion, Inc. (US10657696B2)#653961
• Tracking position of device inside-out for virtual reality interactivity — Sony Interactive Entertainment America Llc (US10535153B2)#653962
• Augmented reality system with spatialized audio tied to user manipulated … — Magic Leap, Inc. (US11231770B2)#653963
• Big data-based autonomous flight drone system and autonomous flight method … — Rgblab Co., Ltd. (US20210390867A1)#653964