KITESYSTEM

Description

[0001] The invention relates to a kite system comprising a kite, a boom, a gondola, and a tow rope. The kite is connected to the gondola via the boom. The tow rope extends between the gondola and a ground-based anchor point.

[0002] The kite can be moved along flight paths that are essentially perpendicular to the tow rope by appropriately adjusting its aerodynamic properties. As the kite moves along these paths, a pulling force is exerted on the tow rope. This pulling force can be used, for example, to generate electrical energy or as propulsion for a vessel.

[0003] Particularly when used on a ship or in offshore energy production, a kite may unintentionally end up in the water. A tow rope stretched between an attachment point and a kite at sea can pose a hazard to shipping. Retrieving and recovering a kite adrift in the water can be difficult because the water can exert considerable force on the kite. Furthermore, damage to the kite can occur if high forces are transmitted to the attachment point via the tow rope. A state-of-the-art kite is disclosed, for example, in document WO2005 / 100150.

[0004] The invention is based on the objective of providing a kite system that reduces the dangers associated with a kite unintentionally landing in the water. Starting from the aforementioned prior art, this objective is achieved by the features of the independent claim. Advantageous embodiments are specified in the dependent claims.

[0005] In the kite system according to the invention, a tensile force exerted by the kite is transmitted via a traction cord that extends from the kite, through the boom and the tow rope, to the attachment point. A release device, triggered upon contact with water, is arranged within the traction cord. The release device is an element of the traction cord through which the tensile forces acting between the kite and the attachment point are transmitted completely or partially.

[0006] The invention is based on the idea of ​​reducing the tensile forces emanating from a kite drifting in water by severing a section of the towing line involved in transmitting these forces. A kite landing in water is not an event anticipated in the normal operation of the kite system, which is why it cannot be assumed that all control mechanisms intended for normal operation are still functional. The invention proposes designing the severing device to be triggered by contact with water. In this way, the severing of the connection within the towing line functions reliably even if other control devices have failed.

[0007] A landing point is considered ground-based if the kite's pulling force prevents it from lifting off the Earth's surface. A ground-based landing point can be permanently attached to the ground. Ground-based landing points can also be located on a ship, a floating pontoon, or a mobile system on land.

[0008] The towline extending between the kite and the attachment point can comprise a first section in which the tensile force is transmitted via a plurality of parallel strand elements. This section of the towline can correspond to the line boom extending between the kite and the gondola. The release device can be located within one of these parallel strand elements. Even after the release device is triggered, this embodiment maintains a connection between the kite and the attachment point via the remaining strand elements, allowing tensile forces to be transmitted.

[0009] The traction line can branch into multiple parallel strands between the release device and the kite, so that after the release device is triggered, there are several points on the kite where no traction force is exerted. It is also possible for the kite system to include multiple release devices arranged parallel to each other within the traction line. In particular, it is possible to disconnect all strands of the first section, thus severing the connection to the second section of the traction line.

[0010] The traction cord can include a second section in which the entire pulling force is transmitted via a single cord element. This second section of the traction cord can correspond to the tow rope that extends between the gondola and the attachment point. The release device can be located within this second section of the traction cord, so that the connection between the kite and the attachment point is completely severed when the release device is triggered.

[0011] A release device arranged within the tow rope can be positioned adjacent to the gondola. In particular, the distance between the gondola and the release device can be less than 20%, preferably less than 10%, and more preferably less than 2% of the length of the tow rope when the tow rope is fully extended. After such a release device is triggered, the tow rope can be hauled in without significant resistance. The kite must be retrieved in a separate operation, for example, by sailing a vessel to the kite, which is floating freely in the water, and bringing the kite on board.

[0012] If, however, the pull cord is only partially severed when the release mechanism is triggered, it becomes possible to pull the kite, along with the pull cord, to the attachment point. For this to work, it is advantageous if the kite is brought into a state by the release mechanism in which it can be pulled through the water with minimal resistance.

[0013] In normal operation of the kite system, the control line is designed so that the kite covers a large area perpendicular to the direction of pull. This is achieved by attaching the boom to the kite at multiple points, which span a large area in a plane perpendicular to the direction of pull. The kite system can be designed such that the points of attachment to the control line still span an area perpendicular to the direction of pull, which corresponds to a maximum of 50%, preferably a maximum of 20%, and more preferably a maximum of 10% of the area covered in normal operation.

[0014] The kite can extend perpendicular to the direction of movement from a first outer section, through a central section, to a second outer section. The kite system can be designed so that, upon activation of the release mechanism, the strand elements extending to the first and second outer sections are severed. The pull line is then only connected to the central section of the kite. The peripheral sections can move backward as the kite is pulled through the water.

[0015] Alternatively, the kite system can be designed so that, after the release mechanism is triggered, only an edge section of the kite remains connected to the tow line, while the line elements extending to the opposite edge section and to a central section are severed. The edge section of the kite still connected to the tow line can be a transversely peripheral section, a longitudinally forward section, or a longitudinally aft section. The longitudinal direction is defined as the direction parallel to the kite's direction of movement, which is typically a direction parallel to the kite's airfoil profile.

[0016] The separating device can include a locking mechanism that allows it to switch between a closed and an open state. In the closed state, a tensile force can be transmitted via the separating device located in the tension member. In the open state, the tension member is separated at that point.

[0017] The separating device can include a release element that reacts to contact with water. The release element can be in mechanical contact with the locking mechanism, so that the separating device is held in the closed position as long as the release element does not come into contact with water. For example, the release element can have a body made of a water-soluble material, so that the body dissolves upon contact with water, thereby releasing an actuation path for the locking mechanism. The body could be, for example, a cellulose tablet or a salt tablet. The locking mechanism can be spring-loaded, so that it automatically returns to the open position after the actuation path is released.

[0018] It is also possible that the release element is designed as a trigger sensor that sends a control signal upon contact with water. This control signal can be transmitted to the locking mechanism via cable or radio link. Upon receipt of the control signal, the locking mechanism can be actuated, causing the separating device to switch from the closed to the open state. This also includes embodiments in which the locking mechanism is actuated in other ways, for example, pneumatically or hydraulically.

[0019] The separating device can be designed to switch between the open and closed states without triggering the release element. In particular, the separating device can have a locking mechanism that can be actuated without triggering the release element. In this way, the separating device can be used, for example, to establish or disconnect a connection between the tow rope boom and the gondola or between the gondola and the haul rope. The release element can remain unchanged and retain its function of triggering upon contact with water.

[0020] The actuating element can be spring-loaded to hold the separating device in the closed position. The spring force holding the actuating element can be dimensioned so that it can be overcome manually.

[0021] In one embodiment, the cutting device is a shackle that opens automatically after the release element is triggered. Alternatively, cutting devices designed to separate the tension member or a portion thereof by mechanical action, such as cutting, are also possible. In one embodiment, the cutting device is a pyrotechnic cutter. Cutting devices that act on a portion of the tension member by burning or blasting are also possible.

[0022] The release mechanism can be configured to activate only upon contact with saltwater, but not with freshwater. This can be useful when the kite is being flown over the sea, so that a crash would result in contact with saltwater. Conversely, contact with rainwater would not trigger the release mechanism.

[0023] Additionally or alternatively, the separating device can be designed so that the release element is protected from rainwater. For example, the release element can be covered from above or only accessible from the outside via a channel, so that the release element only triggers after immersion in water.

[0024] A separating device with one or more of the aforementioned features has independent inventive content, even without being used in connection with a kite system according to the invention.

[0025] The kite system can also include the land-based anchor point to which the tow rope extends. This anchor point can be part of a floating structure, such as a pontoon or a ship. The kite system can also be a component of a device for generating electrical energy. This device can include a generator driven by a winch. Alternatively, the kite system can be connected to a ship's anchor point, allowing the kite system to generate propulsion for the ship.

[0026] The invention is described below by way of example with reference to the accompanying drawings and advantageous embodiments. The drawings show: Fig. 1: a device for generating electrical energy with a kite system according to the invention; Fig. 2: a schematic representation of an operating state of the device. Fig. 1 ; Fig. 3-4: Details of the kite system made of Fig. 1 in enlarged view; Fig. 5: a kite system according to the invention; Fig. 6: an alternative embodiment of a kite system according to the invention; Fig. 7: the kite system made of Fig. 6 in a different state; Fig. 8: another embodiment of a kite system according to the invention; Fig. 9: the kite system made of Fig. 8 In another state, Fig. 10: an embodiment of a separating device of a kite system according to the invention; Fig. 11: a ship with a kite system according to the invention.

[0027] One in Fig. 1 The device shown for generating electrical energy comprises a kite system 23 according to the invention, which is connected to a winch 16 via a pull rope 15. The winch 16 forms a pivot point within the meaning of the invention. The kite system 23 comprises a kite 14, which is connected to a gondola 25 via a boom 24.

[0028] Coupled with the winch 16 is an electric power machine 17, which operates as a generator in a first operating state and as a motor in a second operating state. The power machine is connected to a public transmission network 19 via an electrical power train 18, which includes a converter and a transformer, so that either electrical energy generated by the power machine 17 can be fed into the transmission network 19 or the power machine 17 can be operated as a motor using electrical energy drawn from the transmission network 19. The device includes a control unit 20, which is designed to control the interaction of the device's components.

[0029] The winch 16 with the power machine 17 and the components of the electrical wiring harness 18 is arranged on a floating pontoon 12, which floats on the sea 11. The floating pontoon 12 is connected to an anchor 10 located on the seabed 13.

[0030] The control unit 20 includes an antenna 21, enabling the exchange of control signals 22 with the gondola 25 via a radio link. Specifically, the control unit 20 sends control signals to the gondola 25 to steer the flight path of the kite 14. Using these control signals, the length of the control lines on the line boom 24 is changed, thereby influencing the flight direction of the kite 14.

[0031] In the embodiment according to Fig. 2 The kite 14 is guided along a figure-eight pattern oriented essentially perpendicular to the wind direction (W). As the kite 14 follows this path, a tractive force is exerted on the tow rope 15, which drives the power machine 17 via the winch 16. The power machine 17, operating as a generator in this state, converts the mechanical energy into electrical energy and feeds it into the public transmission grid 19 via the power train 18. It is also possible to store some of the generated energy in electrical form in an energy storage device of the power train 18. Electrical energy can be generated in this way until the length of the tow rope 15 is exhausted and the tow rope 15 is fully extended by the winch 16. The tow rope 15 is then retracted by the power machine 17, which is operating as a motor, before electrical energy can be generated again.

[0032] The line boom 24 of the kite system 23 according to the invention comprises according to Fig. 3 Active steering lines 26, passive steering lines 27, and fixed lines 28, each attached to the gondola 25, branch out from nodes 29 into a plurality of ends attached to the kite 14. The fixed lines 28 extend from an end rigidly connected to the gondola 25 to a central section of the kite 14. The active steering lines 26, whose length is adjustable, extend from the gondola 25 to two peripheral sections of the kite 14. The passive steering lines 27, which are redirected over pulleys 30 on the gondola 25, are attached to the kite 14 between the fixed lines 28 and the active steering lines 26.

[0033] The direction of movement of the kite 14 can be controlled by adjusting the length of the active steering lines 26. When adjusting the active steering lines 26, the passive steering lines 27 are guided over the pulleys 30, whereby the length of the passive steering lines 27 from the kite 14 over the pulleys 30 back to the kite 14 remains unchanged.

[0034] The Kite 14 forms an airfoil profile that extends longitudinally from a Fig. 3 visible front surface 31 via an outer surface 32 and an inner surface 33 to a point in Fig. 3 The kite 14 extends to a non-visible rear end. Inside the kite 14 is a cavity which is pressurized during normal operation of the kite system. The kite 14 includes openings 34 formed in its frontal surface 31, through which air can enter the interior and through which the positive pressure is built up when the kite 14 is in motion.

[0035] According to Fig. 5 The gondola 25 is attached to the haul rope 15 via a release device 40. The release device 40 is triggered upon contact with water 40 and disconnects the connection between the gondola 25 and the haul rope 15. If the kite 14 falls into the sea 11 due to an unusual operating situation, the release device 40 comes into contact with the seawater and the connection between the gondola 25 and the haul rope 15 is released. The haul rope 15 can then be retrieved using the winch 16 without requiring significant force. This has the advantage that any potential hazard to shipping caused by the haul rope 15 stretched between the winch 16 and the gondola 25 can be quickly eliminated. After the release device 40 is triggered, the kite 14 and the gondola 15 drift freely on the sea and can be recovered by a vessel.

[0036] In Fig. 10 Figure 1 shows an embodiment of a separating device 40 according to the invention in the form of a shackle. The shackle comprises a shackle body 41 formed as a cast part. A locking piece 43 is attached to a front end of the shackle body 41 via a hinge connection 42, which is engaged by a latch 44 in the Fig. 10 The closed state shown is maintained. At the opposite rear end of the shackle, an eyelet 45 is screwed into the shackle body 41. During operation of the kite system 23 from Fig. 5 The tow rope 15 is connected to the eyelet 45 and the front end of the shackle is attached to the gondola 25.

[0037] The shackle includes a retaining element 46, which holds the bolt 44 in the closed position. The retaining element 46 is arranged in a bore of the shackle body 41 and is held in place by a retaining spring 47 in the Fig. 10 The front position shown is maintained. The bore is closed with a plug 48. The retaining spring 47 is supported by a cellulose tablet 49 at the front end of the plug 48.

[0038] If the shackle falls into the sea 11, the cellulose tablet 49 comes into contact with seawater and dissolves. The retaining element 46 is no longer supported by the plug 48, thus allowing movement for the bolt 44. The bolt 44 is released by the force of a bolt spring 50, which is normally under tension. The locking piece 43 opens and the gondola 25 is separated from the tow cable 15.

[0039] The space in which the cellulose tablet 49 is arranged is connected to the environment by a first channel 51 formed in the plug 48 and by a second channel 52 formed in the closure body 41. Seawater can enter through one of the channels, while air can escape through the other. This prevents the entrapment of air bubbles. The channels 51 and 52 are designed and oriented such that, during normal operation of the kite system 23, rainwater cannot reach the cellulose tablet 49. The cellulose tablet 49 dissolves only after the shackle is immersed in water.

[0040] The shackle can also be opened without dissolving the cellulose tablet 49 by an operator applying pressure to the latch 44 via a gripping surface 53. The retaining spring 47 is dimensioned so that it can be compressed by hand.

[0041] In Fig. 6 The simplified kite boom 24 has three fixed lines 28 extending to a central section of the kite 14, and three steering lines 26 extending to opposite outer sections of the kite 14. The kite system comprises a total of three release devices 40. Two of the three fixed lines 28 are attached to the gondola 25 via the first release device 40, and two of the three steering lines 26 are attached to the gondola 25 via the second and third release devices 40. If the kite 14 falls into the sea 11, the three release devices 40 are released, so that only one of the fixed lines 28 and only one of each of the steering lines 26 remain connected to the gondola 25.The connection is to a front section of the airfoil of the Kite 14, the rear part of the Kite 14 can swing out to the rear: In this state, the Kite 14 forms a flat structure which can be retrieved with the pull rope 15 without having to exert large forces, see . Fig. 7 .

[0042] In the Fig. 8 und 9 An alternative embodiment is shown in which two separation devices 40 are arranged in the simplified depiction of the line boom 24. The first separation device 40 disconnects all three fixed lines 28 from the gondola 25. The second separation device completely disconnects the set of steering lines 26 arranged on one side of the fixed lines 28 from the gondola, so that the kite 14 is connected to the gondola 25 only via the other set of steering lines 26. After the separation devices 40 are released, a flat structure is also formed, which can be pulled through the water without much effort and can be retrieved with the tow rope 15, see [reference]. Fig. 9 .

[0043] In Fig. 11 An alternative embodiment of the invention is shown in which the kite system 23 according to the invention is used to generate a propulsive force for a ship 54. The tow rope 15 is attached to a pivot point 55 of the ship 54.

Claims

1. Kite system comprising a kite (14), a line arrangement (24), a pod (25), and a tension rope (15), wherein the kite (14) is connected to the pod (25) via the line arrangement (24), and wherein the tension rope (15) extends between the pod (25) and a terrestrial attachment point (16, 55), and wherein a tensile force exerted by the kite (14) during operation is transferred via a tension strand (15, 24), which extends from the kite (14) to the attachment point (16, 55) via the line arrangement (24) and the tension rope (15), characterized in that a separating device (40), which is triggered upon contact with water, is arranged within the tension strand (15, 24).

2. Kite system according to Claim 1, characterized in that the tension strand (15, 24) is fully parted when the separating device (40) is triggered.

3. Kite system according to Claim 1 or 2, characterized in that the tension strand (15, 24) comprises a section in which the tensile force is transmitted via a plurality of mutually parallel strand elements (26, 27, 28).

4. Kite system according to Claim 3, characterized in that the separating device (40) is arranged within one of several mutually parallel strand elements (26, 27, 28).

5. Kite system according to Claim 3 or 4, characterized by a plurality of separating devices (40), which are arranged parallel to one another within the tension strand (15, 24).

6. Kite system according to one of Claims 3 to 5, characterized in that the tension strand (15, 24) is partially parted when the separating device (40) is triggered.

7. Kite system according to Claim 6, characterized in that the points of the kite (14) which are attached to the tension strand after the triggering of the separating device (40) generate a surface that is perpendicular to the direction of tension and that still corresponds to a maximum of 50%, preferably a maximum of 20%, as a further preference a maximum of 10%, of the surface generated in normal operation.

8. Kite system according to one of Claims 1 to 3, characterized in that the tension strand (15, 24) comprises a section in which the entire tensile force is transmitted via a single strand element (15), and in that the separating device (40) is arranged within the single strand element (15).

9. Kite system according to one of Claims 1 to 8, characterized in that the separating device (40) comprises a triggering element (49) which is dissolved upon contact with water.

10. Kite system according to one of Claims 1 to 9, characterized in that the triggering element (49) is triggered only upon contact with salt water.

11. Kite system according to Claim 9 or 10, characterized in that the triggering element (49) is protected from contact with rainwater.

12. Kite system according to one of Claims 9 to 11, characterized in that the triggering element (49) is in mechanical contact with a locking mechanism (44) of the separating device (40).

13. Kite system according to one of Claims 9 to 12, characterized in that the separating device (40) has a locking mechanism which can be actuated without triggering the triggering element (49).