US20140361122A1 - System and method for airborne wind energy production - Google Patents
System and method for airborne wind energy production Download PDFInfo
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- US20140361122A1 US20140361122A1 US14/467,413 US201414467413A US2014361122A1 US 20140361122 A1 US20140361122 A1 US 20140361122A1 US 201414467413 A US201414467413 A US 201414467413A US 2014361122 A1 US2014361122 A1 US 2014361122A1
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- glider
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Classifications
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C39/00—Aircraft not otherwise provided for
- B64C39/02—Aircraft not otherwise provided for characterised by special use
- B64C39/022—Tethered aircraft
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C19/00—Aircraft control not otherwise provided for
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C31/00—Aircraft intended to be sustained without power plant; Powered hang-glider-type aircraft; Microlight-type aircraft
- B64C31/02—Gliders, e.g. sailplanes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64C—AEROPLANES; HELICOPTERS
- B64C39/00—Aircraft not otherwise provided for
- B64C39/02—Aircraft not otherwise provided for characterised by special use
- B64C39/024—Aircraft not otherwise provided for characterised by special use of the remote controlled vehicle type, i.e. RPV
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64U—UNMANNED AERIAL VEHICLES [UAV]; EQUIPMENT THEREFOR
- B64U10/00—Type of UAV
- B64U10/60—Tethered aircraft
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03D—WIND MOTORS
- F03D13/00—Assembly, mounting or commissioning of wind motors; Arrangements specially adapted for transporting wind motor components
- F03D13/20—Arrangements for mounting or supporting wind motors; Masts or towers for wind motors
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03D—WIND MOTORS
- F03D5/00—Other wind motors
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03D—WIND MOTORS
- F03D5/00—Other wind motors
- F03D5/02—Other wind motors the wind-engaging parts being attached to endless chains or the like
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- F03D9/003—
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
- F03D—WIND MOTORS
- F03D9/00—Adaptations of wind motors for special use; Combinations of wind motors with apparatus driven thereby; Wind motors specially adapted for installation in particular locations
- F03D9/20—Wind motors characterised by the driven apparatus
- F03D9/25—Wind motors characterised by the driven apparatus the apparatus being an electrical generator
- F03D9/255—Wind motors characterised by the driven apparatus the apparatus being an electrical generator connected to electrical distribution networks; Arrangements therefor
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
- H02G11/00—Arrangements of electric cables or lines between relatively-movable parts
- H02G11/02—Arrangements of electric cables or lines between relatively-movable parts using take-up reel or drum
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B64—AIRCRAFT; AVIATION; COSMONAUTICS
- B64U—UNMANNED AERIAL VEHICLES [UAV]; EQUIPMENT THEREFOR
- B64U10/00—Type of UAV
- B64U10/25—Fixed-wing aircraft
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05B—INDEXING SCHEME RELATING TO WIND, SPRING, WEIGHT, INERTIA OR LIKE MOTORS, TO MACHINES OR ENGINES FOR LIQUIDS COVERED BY SUBCLASSES F03B, F03D AND F03G
- F05B2240/00—Components
- F05B2240/90—Mounting on supporting structures or systems
- F05B2240/92—Mounting on supporting structures or systems on an airbourne structure
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05B—INDEXING SCHEME RELATING TO WIND, SPRING, WEIGHT, INERTIA OR LIKE MOTORS, TO MACHINES OR ENGINES FOR LIQUIDS COVERED BY SUBCLASSES F03B, F03D AND F03G
- F05B2240/00—Components
- F05B2240/90—Mounting on supporting structures or systems
- F05B2240/92—Mounting on supporting structures or systems on an airbourne structure
- F05B2240/921—Mounting on supporting structures or systems on an airbourne structure kept aloft due to aerodynamic effects
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
- F05B—INDEXING SCHEME RELATING TO WIND, SPRING, WEIGHT, INERTIA OR LIKE MOTORS, TO MACHINES OR ENGINES FOR LIQUIDS COVERED BY SUBCLASSES F03B, F03D AND F03G
- F05B2240/00—Components
- F05B2240/90—Mounting on supporting structures or systems
- F05B2240/92—Mounting on supporting structures or systems on an airbourne structure
- F05B2240/923—Mounting on supporting structures or systems on an airbourne structure which is a vehicle
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/70—Wind energy
- Y02E10/728—Onshore wind turbines
Definitions
- the present invention generally relates to a system for electric power production from wind and, more particularly, to a method for operation of a system for electric power production from wind, and to a glider for a system for production power from wind and to the use of a glider for production of electric power from wind.
- the production of electric power from wind is generally accomplished by airfoils or structures with an aerodynamic profile, which produce lift forces upon exposure to wind. Thereby, energy is extracted from the wind, and the energy can be converted into electricity by, for example, using the lift forces to drive an electrical generator.
- Well known wind turbines include a rotor with aerodynamically profiled rotor blades, wherein the lift forces of the rotor blades cause the rotor to turn.
- the rotor is mounted to an electrical generator that is, for example, located on top of a tower, for production of electricity.
- U.S. Pat. No. 6,254,034 B1 discloses a tethered kite travelling a closed cycle. While the kite travels downwind, it is driven by the wind and the tether is pulled from a windlass drum that is rotationally connected to the rotor of an electrical generator. The rotor of the generator spins and produces energy. The cycle is completed by travelling the kite upwind back to the starting point. Net energy is gained when the energy generated during downwind travel of the kite exceeds the energy required for the upwind return.
- Another option is to alter the angle of attack or the equivalent supporting plane surface of the kite at the end of the downwind travel, thereby reducing the pull of the kite on the tether.
- the kite is now pulled back by switching the generator to motor operation, wherein due to the reduced pull less energy is consumed than has been produced during the preceding downwind travel.
- a fraction of the generated energy has to be spent in the interest of safety, because controllable flight of the kite requires a certain amount of pull on the tether.
- the underlying problem of the invention is to provide for electric power production from wind using an airborne airfoil, wherein in particular the integrated energy yield and/or the operational safety are to be improved with respect to the prior art described above.
- a system for electric power production from wind including a glider, the glider having an airfoil, on-board steering unit for pitching, rolling and yawing the glider when airborne, a flight controller for operation of the steering unit, and a connection unit for a tether.
- the system further includes a ground station including a reel for the tether, a rotating electrical machine connected to the reel, and a ground station controller for operation of the reel and the rotating electrical machine.
- the system further includes a master controller for controlling operation of the system in at least first and second operation modes.
- a first operation mode of the system is provided for electric power production with the rotating electrical machine from a rotation of the reel induced by reeling out the tether using a lift force generated upon exposure of the airfoil of the airborne glider to wind.
- a second operation mode of the system is provided for system recovery by driving the reel with the rotating electrical machine, thereby reeling in the tether onto the reel.
- a glider or sailplane in terms of the invention in particular is a fixed wing aircraft, wherein the on-board steering unit allows for full flight maneuverability of the glider around its longitudinal axis, its lateral axis and its vertical axis.
- these three principle axes form a Cartesian coordinate system, wherein the origin of said coordinate system is defined to be at the centre of gravity of the glider.
- the longitudinal axis relates to the direction of motion
- the vertical axis relates to the direction of lift
- the lateral axis is essentially horizontal to complete a Cartesian coordinate system.
- the glider for instance includes a fuselage and a main wing, wherein the main wing constitutes or comprises an airfoil.
- the longitudinal axis is essentially parallel to the fuselage
- the lateral axis is essentially parallel to the main wing
- the vertical axis is perpendicular to both the longitudinal and the lateral axis.
- the glider can have another airplane configuration, for instance an all-wing aircraft, with appropriate definitions of the principle axes.
- rolling refers to a rotation of the glider around its longitudinal axis
- pitching refers to a rotation of the glider around its lateral axis
- yawing refers to a rotation of the glider around its vertical axis.
- the steering unit of the glider includes control surfaces to aerodynamically exert torque on the glider around one or more of the glider's principle axes.
- control surfaces include so-called ailerons to mainly induce rolling, so-called elevators to mainly induce pitching, and a so-called rudder to mainly induce yawing.
- a control surface can induce a rotation around an arbitrary axis that does not correspond to one of the principle axes of the glider.
- the steering unit of the glider further includes actuators, such as electric motors or hydraulic systems with pumps and cylinders, for moving the control surfaces.
- actuators such as electric motors or hydraulic systems with pumps and cylinders, for moving the control surfaces.
- These actuators are, for instance, powered by an on-board power source, such as a battery.
- a glider provides the advantage of low aerodynamic resistance or drag and a high aerodynamic lift due to the fixed wing with rigid aerodynamic profile or airfoil, respectively. This is in particular beneficial, because the energy effectively extracted from the wind strongly depends on lift and drag, in particular on the so called lift-over-drag-ratio.
- the tether has a drag-optimized shape or structure. This can for instance be a helical structure, which turned out to have a lower resistance or drag than a tether with a circular cross section.
- Another advantage of a glider is that the flight of the glider is stable even without any load on the tether, while a kite requires a certain pull on the tether for stable flight. Therefore, the invention allows for zero tether load and correspondingly minimum energy consumption during system recovery in the second operation mode.
- the flight of the glider is controllable and stable by itself, in particular without any connection to the ground. Even in case of system failures, for example when the generator load on the reel is lost or the tether breaks, the glider can be landed safely.
- the system according to the invention thus provides for particularly effective and safe production of electric power from wind energy.
- the flight controller provide for a first flight control mode for automated flight operation and for a second flight control mode for manual operation, in particular via a remote control unit with wired or wireless connection to the flight controller.
- the first flight control mode provides for automated operation with optimised energy yield, wherein the second flight control mode allows for manual intervention during maintenance and testing of the system as well as for emergency interventions in the case of failures. This way, the operation is simplified and the safety in operation is further enhanced.
- the glider includes an air speed sensor for determining an air speed of the glider.
- air speed refers to the speed of movement or velocity, respectively, of the glider with respect to the surrounding air.
- the air speed in general differs from the ground speed of the glider, i.e. the velocity of the glider relative to the ground.
- the air speed sensor preferably is a directional sensor providing both the magnitude and the direction of the glider's air speed.
- the air speed sensor is preferably arranged at the glider.
- the air speed sensor can also be positioned at the tether, wherein the position of the air speed sensor at the tether is preferably close to the connection between the tether and the glider.
- the glider includes a control unit incorporating both the flight controller of the glider and the master controller of the system.
- the connection between the flight controller and the master controller is particularly short in a physical sense, making it fast and robust against distortion and failure.
- fast feedback between the flight operations which is rather complex and influenced by eventually fast changing wind conditions, and the operation of the system as a whole is or can be established.
- the ground station further comprises a tension sensor for determining a tension of the tether.
- the tension of the tether is a good indicator for the overall system load and can, for instance, be used as an input parameter for controlled reeling out of the tether.
- the tension sensor is, for example, arranged at the ground station or integrated into the tether, wherein the tension sensor preferably is or can be connected to the ground station controller.
- the ground station controller is preferably designed for retaining a predetermined target tension of the tether, in particular during reeling out the tether.
- the ground station controller preferably is designed for retaining a predetermined reel speed, in particular during reeling in the tether.
- reel speed refers to the length of tether being reeled in or reeled out in a given amount of time.
- the reel speed is in particular correlated with the rotational velocity of the rotating reel.
- Retaining a predetermined reel speed which is, for instance, accomplished by retaining a predetermined target rotational velocity of the reel, is very effective in reducing sagging of the tether when the lift force or load exerted on the tether is low.
- the tether includes a power transmission line between the glider and the ground station.
- the various systems of the glider such as electronics of the flight controller or actuators of the flight controller, are powered from the ground.
- the glider can comprise a relatively low capacity power source allowing for control and safe landing of the glider.
- the tether preferably includes a data transmission line between the glider and the ground station, for instance for communication between the flight controller, the ground station controller and/or the main controller. Additional, alternative or redundant communication channels can for instance be realized by wireless transmission.
- the present invention further includes a method for operation of a system for electric power production from wind, the system including a glider connected to a tether and a ground station with a reel for the tether, wherein the system is operated alternately in a first operation mode for power production and a second operation mode for system recovery.
- the first operation mode includes:
- the second operation mode includes:
- the integrated energy yield i.e. the amount of electric power produced at given wind conditions in certain amount of time, is particularly optimized when the lift force generated by the airfoil is maximized during operation of the system in the first operation mode and minimized during operation in the second operation mode.
- the energy yield is further increased when the time required for reeling in the tether, that is the minimum duration for the system to be operated in the second operation mode, where no electric power is produced, is as short as possible.
- the maneuverability of a glider allows for a first flight pattern, which is in particular a high lift flight pattern, where the glider for instance flies downwind of the ground station across the wind along a flight path, which for instance resembles a circular or eight-shaped figure. Highest lift forces are generally achieved in fast cross-wind flight of the glider.
- the glider for instance is brought in a descent towards the ground station.
- the pull on the tether is reduced and eventually brought to zero. This way, minimum energy is consumed for spinning the reel, while no energy is required to pull the glider towards the ground station.
- the speed of the glider towards the ground station is maximized and the dead time, i.e. the time required for system recovery, is minimized.
- reeling out the tether is controlled to retain a target tension of the tether, which in particular is predetermined as a function of an air speed of the glider.
- the air speed of the glider in particular is the velocity of the airfoil relative to the air, and thus is an indication for the lift force generated by the airfoil.
- the target tension does not have to be constant with time.
- the air speed which is a vector quantity and has a magnitude as well as a directional component, will change over the course of the flight pattern with varying angle between direction of flight of the glider and the wind direction. Also, changes in the wind conditions result in air speed differences.
- reeling in the tether is controlled to retain a target reel speed, which in particular is predetermined as a function of an air speed of the glider.
- the target reel speed can also be predetermined from other observables, for instance a ground speed of the glider.
- a feature in particular or particularly means that the feature is an optional feature.
- FIG. 1 schematically illustrates a system according to the invention.
- FIG. 2 a schematically illustrates operation of a system according to the invention in a first operation mode.
- FIG. 2 b schematically illustrates operation of a system according to the invention in a second operation mode.
- FIG. 3 is a block diagram illustrating the control of a system according to the invention.
- FIG. 1 shows an exemplary embodiment of a system for electric power production from wind according to the invention.
- the airborne or potentially airborne part of the system comprises a glider 10 , which in the embodiment depicted in FIG. 1 is designed to be a fixed wing aircraft.
- the glider 10 comprises a fuselage 12 , a main wing 14 , a tailplane 16 and control surfaces 20 , 22 , 24 . Also shown are the longitudinal axis 32 , the lateral axis 34 and the vertical axis 36 , which meet at the centre of gravity 30 of the glider and which constitute the intrinsic coordinate system of the glider.
- the fuselage 12 comprises a tube constructed from fiber reinforced composite material as mechanical backbone between the main wing 14 and the tailplane 16 and a nacelle for electronics, power source, sensors and the like, which is mounted in front of the main wing 14 .
- the main wing 14 can for instance be constructed from a single wing, as in the embodiment depicted in FIG. 1 .
- alternative designs for instance with a separate main wing 14 on either side of the fuselage 12 are within the scope of the invention.
- control surfaces which in the exemplary embodiment comprise ailerons 20 at either side of the main wing 12 , as well as elevators 22 and a rudder 24 at the tailplane 16 .
- the control surfaces 20 , 22 , 24 for instance are hinged surfaces used to induce torque around the principle axes 32 , 34 , 36 of the glider 10 by aerodynamic means.
- Torque around the longitudinal axis 32 is induced by the ailerons 20 , which can be or are operated simultaneously and in opposite directions.
- opposite directions means that when the left aileron is moved upwards with respect to the main wing 14 , the right aileron is moved downwards.
- lift is enhanced on the right side of the main wing 14 and reduced on the left side of the main wing 14 , causing a torque around the longitudinal axis 32 .
- the resulting movement of the glider 10 , a rotation around its longitudinal axis 32 is referred to as rolling.
- a rotation of the glider 10 around its lateral axis 34 which is referred to as pitching, is achieved by the elevators 22 , which are used to increase or decrease the lift at the tailplane, thereby inducing a torque around the lateral axis 34 .
- Rotation of the glider 10 around its vertical axis 36 which is referred to as yawing, is induced by the rudder 24 .
- the glider 10 is connected to the ground station 40 via a tether 44 , which is attached to or connected with the glider 10 at a connection unit, which is preferably arranged close to the centre of gravity 30 of the glider 10 . This way, varying loads on the tether 44 do not significantly impair the balance of the glider 10 in flight.
- excess length of the tether 44 is stored on a reel 42 , which is connected to a rotating electrical machine 46 .
- the rotation electrical machine 46 is connected to an electricity storage and/or distribution system (not shown) such as a power grid, a transformer station or a large scale energy reservoir.
- electricity storage and/or distribution system can be any device or system capable of receiving electricity from and delivering electricity to the rotating electrical machine.
- the system shown in FIG. 1 is alternately operated in a first operation mode for production of electric power, illustrated in FIG. 2 a , and a second operation mode for system recovery, illustrated in FIG. 2 b.
- the glider 10 is steered to follow a high lift flight pattern indicated by line 52 downwind of the ground station 40 .
- the direction of the wind is indicated by arrow 50 .
- the airfoil or the main wing 14 , respectively, of the glider 10 generates a lift force much larger than required to keep the glider 10 at a given altitude.
- the glider exerts a pull on the tether 44 , which is correlated to the excess lift force.
- the pull on the tether 44 is used for reeling out the tether 44 from the reel 42 in direction of arrow R, thereby inducing a rotation of the reel 42 .
- the resulting torque which in particular depends on the diameter of the reel 42 and the force with which the tether 44 is pulled, is transmitted to the rotating electrical machine 46 , where the mechanical energy is transformed to the electric power.
- a gear box is arranged between the reel 42 and the rotating electrical machine 46 , which is not shown in the figures for reasons of simplicity.
- the load on the tether 44 and on the glider 10 can be influenced.
- the glider 10 flies away from the ground station 40 . Keeping the system in the first operation mode thus is limited by the overall length of the tether 44 .
- the rotating electrical machine 46 For recovery of the tether 44 , i.e. for reeling in the tether 44 onto the reel 42 , the rotating electrical machine 46 is operated as a motor rather than as a generator. The necessary power for instance is provided or delivered by the electricity storage and/or distribution system.
- the pull on the tether 44 is reduced by steering the glider 10 to follow a low lift flight pattern indicated by dashed line 54 .
- This low lift flight pattern 54 for instance is a descent or a fast dive of the glider 10 against the wind 50 towards the ground station 40 .
- the low lift flight pattern 54 can also be an approach of the glider 10 towards the ground station 40 without loss in altitude, including a slight gain in altitude.
- the free length of the tether 44 is shortened and the tether 44 is reeled in onto the reel 42 as indicated by arrow R′.
- the pull on the tether 44 is as low as possible in order to minimize power consumption for reeling in the tether 44 and as fast as possible in order to minimize the dead time, i.e. the period of time where the system does not produce electric power.
- These goals are preferably met by controlling reeling in the tether 44 to retain a target reel speed, which in particular depends on the velocity of the glider 10 approaching the ground station 40 , which for instance can be derived from an air speed of the glider 10 .
- FIG. 3 shows a block diagram of an exemplary control scheme for the system described above.
- the control scheme provides for a modular design with a flight controller 64 , a ground station controller 66 and a master controller 62 .
- the flight controller 64 is designed to control and/or regulate the devices and actuators associated to flight operation of the glider 10 .
- these include but are not limited to ailerons 20 , elevators 22 and rudder 24 of the glider 10 .
- the flight controller 64 includes algorithms and feedback loops for automated flight operation of the glider 10 . It will be appreciated by those skilled in the art that there will be appropriate sensors connected to the flight controller 64 for determining and monitoring the flight conditions, wherein an air speed sensor 18 is shown in FIG. 3 as one example.
- the ground station controller 66 has the purpose of controlling and/or regulating the components of the ground station 40 , in particular the reel 42 and the rotating electrical machine 46 . It will be appreciated by those skilled in the art that the conversion of mechanic energy to electric power, i.e. the operation of the rotating electrical machine 46 as a generator, as well as reeling in the tether 44 , i.e. the operation of the rotating electrical machine 46 as a motor, is also controlled and/or regulated by the ground station controller 66 .
- Both the flight controller 64 and the ground station controller 66 in particular provide for different behaviour associated with different operation modes of the system according to the invention.
- the operation mode of the system itself in particular a first operation mode for production of electric power and a second operation mode for system recovery, is controlled and/or regulated by a master controller 62 .
- the master controller 62 preferably includes or provides automated decision making and switching between one operation mode and the other.
- the flight controller 64 , the ground station controller 66 and the master controller 62 are connected to each other via bi-directional communication channels, wherein in particular the flight controller 64 and the ground station controller 66 communicate status information about the glider 10 or the ground station 40 , respectively, to the master controller 62 .
- the master controller 62 communicates the current operation mode of the system to both the flight controller 64 and the ground station controller 66 , wherein control and/or regulation of the glider 10 and the ground station 40 is performed independently by the flight controller 64 and the ground station controller 66 , respectively.
- the modular design of the control scheme shown in FIG. 3 has the advantage that operational safety of the glider 10 and the ground station 40 , which are normally separated by several hundred meters, is guaranteed individually even in the case of signal delays, signal distortions and communication channel failures.
- the master controller 62 is arranged in close proximity to either the flight controller 64 or the ground station controller 66 .
- the master controller 62 and the flight controller 64 are preferably both arranged on board the glider 10 and can in particular be combined into a single control unit.
- the airborne glider 10 is not. It is therefore desirable to have the possibility to intervene in the control, in particular the flight control, of the glider 10 .
- the flight controller 64 allows for external access to the flight control via a remote control unit 68 , which is preferably connected to the flight controller 64 via a wireless communication channel.
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- Engineering & Computer Science (AREA)
- Aviation & Aerospace Engineering (AREA)
- Mechanical Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Development (AREA)
- Sustainable Energy (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- General Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Remote Sensing (AREA)
- Wind Motors (AREA)
Priority Applications (1)
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US17/074,833 US11358716B2 (en) | 2012-02-27 | 2020-10-20 | System and method for airborne wind energy production |
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EP12157057.6A EP2631468B1 (en) | 2012-02-27 | 2012-02-27 | System and method for airborne wind energy production |
PCT/EP2013/000478 WO2013127499A1 (en) | 2012-02-27 | 2013-02-19 | System and method for airborne wind energy production |
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EP (1) | EP2631468B1 (pt) |
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Also Published As
Publication number | Publication date |
---|---|
AU2018201966A1 (en) | 2018-04-12 |
DK2631468T3 (en) | 2016-12-12 |
AU2019271968A1 (en) | 2019-12-19 |
JP2015514893A (ja) | 2015-05-21 |
PL2631468T3 (pl) | 2017-07-31 |
WO2013127499A1 (en) | 2013-09-06 |
AU2021273556A1 (en) | 2021-12-16 |
PT2631468T (pt) | 2016-12-02 |
AU2013225398A1 (en) | 2014-09-18 |
CA2864682A1 (en) | 2013-09-06 |
ES2605421T3 (es) | 2017-03-14 |
CA2864682C (en) | 2019-08-27 |
EP2631468B1 (en) | 2016-09-07 |
JP6215849B2 (ja) | 2017-10-18 |
US11358716B2 (en) | 2022-06-14 |
AR090093A1 (es) | 2014-10-15 |
US20210047033A1 (en) | 2021-02-18 |
EP2631468A1 (en) | 2013-08-28 |
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