Method for starting a kite system, control unit for a kite device, and kite device
Patent Information
- Application Number
- AU2025229553
- Authority / Receiving Office
- AU · AU
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2024-02-28
- Filing Date
- 2025-02-03
- Publication Date
- 2026-10-08
Smart Images
Figure 00000000_0000_ABST
Abstract
Description
[0001] The invention relates to a method for launching a kite system and to a control unit for a kite device, wherein the kite device comprises a kite system and a base station. The invention also relates to a kite device.
[0002] Such a kite system, which comprises a pod and a kite, can be coupled to a base station via a tether. By suitable setting of the aerodynamic properties of the kite, the kite system can be moved along flight paths that are oriented substantially perpendicularly to the tether. Such a flight state of the kite is referred to below as free-flying. During the movement of the kite along the flight paths, a tensile force is exerted on the tether. The tensile force can be used, for example, to generate electrical energy or as a drive force for a ship.
[0003] During stoppages or still air phases, the kite system is accommodated in a stowed state at the base station. To put the kite system into operation, a launching process is necessary, with which the kite is brought into a state in which an aerodynamic lift is effective and with which the kite system then rises to the intended operating height. In an intermediate phase of the launching process, a guide line extends between the already free-flying kite system and the ground station. The guide line is needed, for example, in case the launching process must be aborted and the kite system must be hauled back to the ground station. If a launching process is successful, it is no longer necessary in the rest of the procedure for the guide line to be directly connected to the ground station. The guide line then becomes a hindrance to the further rising of the kite system and normal flying operation.
[0004] DE 10 2015 111 224 A1 discloses a method for launching a kite system in which the guide line is guided in the direction of the tether of the kite device using a pivot arm of a launching and landing mast of the base station. This design is complex to produce and expensive to maintain. EP 3 802 313 B1 discloses a kite system, in which multiple folding lines extend between the kite system and a ground station during a launching or landing process. The folding lines are disconnected by a manual intervention during launching and reconnected by a further manual intervention during landing.
[0005] The invention is based on the object of presenting a method for launching a kite system, a control device for a kite device, and a kite device with which the aforementioned disadvantages are reduced. The object is achieved with the features of the independent claims. Advantageous embodiments are specified in the dependent claims.
[0006] In the method according to the invention for launching a kite system, the kite system comprises a kite and a pod, wherein the pod is connected to the kite via a bridle, and wherein the kite system is coupled to a base station via a tether. In an intermediate phase of a launching process, a guide line extends between the free-flying kite system and the base station. The method comprises the following steps. The kite system is steered along a flight path so that the tether is guided in a lateral direction in relation to the wind direction until the guide line bears against the tether. The guide line is moved until the guide line lies in a guide line receptacle of the base station, which receptacle is adjacent to the tether. A distal portion of the guide line is separated from a proximal portion of the guide line.
[0007] The launching process is based on a sequence in which firstly the kite is brought into a starting position from which the kite can unfold. In the starting position, the guide line can form a connection between the ground station and the kite, wherein the guide line can be articulated on the ground station such that a tensile force exerted via the guide line has a different direction than a tensile force exerted using the tether. The angle between a tensile force of the tether and a tensile force of the guide line can be greater than 30°, preferably greater than 45°, further preferably greater than 60°. As soon as the kite is unfolded from the starting position and an aerodynamic lift has formed, the kite system can transition into the free-flying state in which the possible flight paths of the kite system depend on the distance from the ground station at which the kite system is kept by the tether. In the free-flying state, it is no longer necessary to support the kite system by means of the guide line. For the free-flying state, the guide line can be brought into a position, in which it does not hinder the operation of the kite system. So that the kite can be operated at an operating height of several 100 m, for example, the tether must be paid out to a corresponding extent. Because a distal portion of the guide line is separated from a proximal portion of the guide line, it is no longer necessary to pay out the guide line, which has no function during normal flying operation of the kite system, to the same length as the tether.
[0008] The launching process is to be carried out such that the guide line can be used again during a later landing process in order to retract and stow the kite. For this purpose, it is desirable for the guide line to be attached to the kite system in a defined position in the free-flying state of the kite system, such that the guide line can be accessed again during the landing process. The launching process according to the invention has the aim of producing such a defined relationship between the guide line and the kite system.
[0009] Against this background, the method according to the invention comprises a step, by way of which the guide line is guided toward the tether before the two portions of the guide line are disconnected. Before this step, there can be a state, in which the spatial relationship of the guide line relative to the tether is undefined. The kite system can be in a state, in which it is already flying independently and in which no tensile force is exerted via the guide line. The guide line can sag and move in an undefined manner relative to the tether under the influence of the weight force of the guide line, the influence of the wind, and the influence of other environmental conditions. If the guide line were to be disconnected in this state, it would be difficult to catch a free end of the guide line again during the subsequent landing process. By guiding the guide line toward the tether, a state is produced, in which the guide line touches the tether. When the guide line touches the tether, the position of the guide line relative to the tether is defined at least in one dimension. The defined position relates to the portion of the guide line and the portion of the tether, in which contact exists between the two. In this state, other portions of the guide line and other portions of the tether do not readily have a defined position relative to one another.
[0010] The invention is based on the concept of using the tether to direct the guide line into the desired position starting from the state, in which the guide line bears against the tether. The invention has recognized that, in the launching phase, a certain spatial arrangement is produced between the guide line and the tether, which arrangement results when the kite is oriented in a predefined manner relative to the wind in the course of the launching process. This spatial arrangement is utilized to guide the guide line along the tether and thus bring the guide line into a position in which the two portions can be separated from one another such that they can be reconnected in a later phase. For example, the possibility of reconnecting the distal portion of the guide line to the proximal portion can be used during landing of the kite system.
[0011] In the intermediate phase of the launching process, a part of the guide line that is attached to the base station can lie upwind of the tether, and a part of the guide line situated between the base station and the kite system can lie downwind of the tether. For this purpose, the length of a part of the guide line situated between the base station and the kite system can in particular be adjusted to a suitable length, and / or a part of the guide line attached to the base station can be moved to a suitable height. In the lateral direction, the position of the guide line relative to the tether can be undefined. This can mean, in particular, that there is a distance in the lateral direction between the guide line and the tether, and that there is no touching between the guide line and the tether. Proceeding from such a configuration, a state in which the guide line bears laterally against the tether can be brought about by moving the tether transversely to the wind direction, i.e., in a lateral direction in relation to the wind direction. In other words, by means of the movement in the lateral direction, the tether can be guided toward the guide line until the guide line touches the tether. The guide line can bear against a portion of the tether which is arranged between the pod and the base station.
[0012] To be able to adjust the length of the guide line, the kite device can comprise a guide line winch. The guide line winch can be provided with a motor drive in order to be able to retract the guide line. The guide line winch can comprise a brake to fix the length of the guide line. The brake can be released in order to bring the guide line winch into a state in which the guide line can be paid out by applying a tensile force. The tensile force can result, for example, from a wind load acting on the guide line. It is also possible for the guide line winch to be motor-driven for payout. Starting from a state, in which a tensile force is exerted on the kite via the guide line, the guide line can be paid out, such that the guide line sags between the ground station and the kite system. The guide line can be paid out so far that the lowest point of the guide line is in a position which lies below the pod.
[0013] A part of the guide line that lies upwind of the tether can be moved downwards in order to direct the guide line to the guide line receptacle of the base station. In this way, the guide line slides downwards along the tether into the region in which the tether transitions into the base station. According to the invention, a guide line receptacle is arranged in this region, in which receptacle the guide line is accommodated when the guide line slides downwards along the tether. Preferably, this takes place such that a deflection point within the guide line is defined by the guide line receptacle. By hauling the guide line in, a specific longitudinal position of the guide line can be guided toward the guide line receptacle. After the guide line has been brought into a defined position relative to the tether in this way, the distal portion of the guide line can be separated from the proximal portion of the guide line. This can be done via a coupling, which can be arranged at the relevant longitudinal position of the guide line. After the guide line has been disconnected, the tether can be paid out without a connection to the base station via the guide line still existing.
[0014] Owing to the aerodynamic lift of the kite, the tether is kept under tension as soon as the kite system is free- flying. Free-flying means that, apart from the tether, there are no further connections between the base station and the kite system by means of which the position of the kite system relative to the base station is defined. In the free-flying state, the guide line can be disconnected from the ground station or paid out so far that a tensile force influencing the flying state of the kite system is no longer exerted via the guide line. When the kite system is free-flying, it is at a distance, defined by the length of the tether, from the base station. The kite system can move in a direction transversely to the tensile force along paths guided by the tether.
[0015] In the intermediate phase in which the kite system is already in a free-flying state, the guide line can be paid out to a length that is, for example, between 5% and 40%, preferably between 10% and 30%, greater than the length of the tether. In this way, it can be ensured that the guide line has enough play to come to bear against the tether in the desired manner, while on the other hand the guide line is prevented from sagging down to the ground or water surface. The indication of the length relates to the instantaneous length of the tether between the base station and the kite system and to the instantaneous length of the guide line between the base station and the kite system.
[0016] To keep the sequence as easily controllable as possible, it is advantageous when the length of the tether and the length of the guide line are kept constant while the guide line slides along the tether in the direction of the guide line receptacle. Since the kite has not yet reached its operating height in this phase, this means that the rising of the kite is interrupted before the kite has reached its operating height in this variant of the method. In other words, there is a phase of the launching process in which the tether is no longer paid out.
[0017] The base station can be provided with an infeed device that receives the tether coming from the kite system. The infeed device can form the first point of the base station that touches the tether coming from the kite system. The infeed device can be part of a deflection pulley system via which the tether is guided. The deflection pulley system can comprise a frame that bears a deflection pulley. The infeed device can be mounted pivotably relative to the frame. The infeed device can be pivotable about an axis that coincides with the rotational axis of the deflection pulley.
[0018] The base station can comprise a base frame that bears the deflection pulley system. The frame of the deflection pulley system can be mounted pivotably relative to the base frame of the base station. The direction of the pivot axis between the frame of the deflection pulley system and the base frame of the base station can form a right angle with the direction of the pivot axis between the infeed device and the frame of the deflection pulley system. By means of a movement about the two pivot axes, the plane of the deflection pulley and the direction of the infeed device can follow the pulling direction of the tether. In this way, it is possible for the deflection pulley system always to be correctly aligned with the pulling direction of the tether, independently of the position currently assumed by the kite system on its flight path.
[0019] The guide line receptacle can be a part of the deflection pulley system. The deflection pulley system can be designed such that the guide line receptacle is attached to the infeed device. The guide line receptacle can be arranged adjacently to an infeed point of the base station, i.e., the point of the base station that first touches the tether coming from the pod. The deflection pulley system can comprise a guide gate with which the guide line is lifted off the tether and directed into the guide line receptacle. The guide gate can be designed as an infeed slope, for example.
[0020] After the distal portion has been separated from the proximal portion of the guide line, the proximal portion of the guide line can be held on the deflection pulley system. After the distal portion has been separated from the proximal portion of the guide line, the distal portion of the guide line can be held on the tether. The deflection pulley system can comprise a sleeve in order to hold the guide line against the tether. A part of the guide line receptacle can be formed in the sleeve. A detachable connection can be provided between the sleeve and the deflection pulley system. The sleeve can be connected to the deflection pulley system as long as the proximal portion and the distal portion of the guide line are connected to one another. The sleeve can be separated from the deflection pulley system when the distal portion is separated from the proximal portion of the guide line. Conversely, it is also possible to separate the guide line by detaching the sleeve from the deflection pulley system. The sleeve can be detachably connected to the deflection pulley system. The connection can be detached by exerting a tensile force on the deflection pulley system and / or on the guide line receptacle using the tether. Alternatively, the connection to the deflection pulley system could be detached by means of an actuator.
[0021] The sleeve can be held on the tether in a fixed longitudinal position. The sleeve can be held on the tether using a locking mechanism. The locking mechanism can block a movement of the sleeve relative to the tether in one direction and permit said movement in the opposite direction. The locking mechanism can be designed such that it does not permit any rotation of the sleeve relative to the tether. This has the advantage that, when the tether is retracted, the sleeve runs back into the infeed device of the deflection pulley system with the correct orientation or orients itself as it runs in. Alternatively, the correct orientation on docking could also be ensured by an appropriate contour between the sleeve and the infeed device. The sleeve can be rotatable relative to the locking mechanism.
[0022] The distal portion and the proximal portion of the guide line can be connected to one another via a coupling. The coupling can be arranged at a longitudinal position of the guide line which runs into the guide line receptacle when the guide line is hauled in. The coupling can be separated by exerting a tensile force on the deflection pulley system and / or on the guide line receptacle using the tether. Alternatively, the coupling can be separated passively when the coupling is arrested in the guide line receptacle. It is also possible to trigger separation of the coupling by a control signal from a control unit. The detachment of the sleeve from the deflection pulley system and the separation of the coupling can take place in a single process.
[0023] The side of the tether on which the guide line comes to lie depends on the individual case. If the guide line is to the left of the tether, the guide line cannot be brought to bear against the tether by a movement of the tether from left to right. It is then not possible to direct the guide line along the tether into the guide line receptacle. To determine whether the process has been successful, it can be determined whether the guide line is lying in the guide line receptacle using a sensor. The sensor can be an optical sensor, for example.
[0024] If the introduction of the guide line into the guide line receptacle was not successful, the process can be repeated. For this purpose, the guide line can be moved into a position in which it can bear against the tether. The movement direction can be opposite the preceding movement with which the attempt was made to direct the guide line into the guide line receptacle. If the guide line is in a suitable starting position, the kite system can be actuated such that the tether is guided in a lateral direction in relation to the wind direction, wherein the lateral direction is opposite the lateral direction during the preceding attempt. It is generally the case that a movement parallel to the wind direction can be superimposed on the movement of the tether in the lateral direction. A lateral movement within the meaning of the invention is present when the movement of the tether has a component in the lateral direction.
[0025] The base station can comprise a first guide line receptacle and a second guide line receptacle. The guide line receptacles can be a part of the deflection pulley system, in particular a part of the infeed device. The guide line receptacles can be arranged such that the tether lies between the guide line receptacles.
[0026] The ground station of the kite device can comprise a launching and landing mast. In an early phase of the launching process before the intermediate phase, the kite system can be held on the launching and landing mast. In one embodiment, the kite system is held on a mast adapter that is attached to the launching and landing mast in a height-adjustable manner. The mast adapter can define an infeed point for the guide line. The guide line can extend through the mast adapter to the guide line winch. The step according to the invention of moving the guide line in order to direct the guide line into the guide line receptacle can be carried out by displacing the mast adapter along the launching and landing mast. In particular, the mast adapter can be displaced downwards along the launching and landing mast in order to direct the guide line into the guide line receptacle. If the attempt to bring the guide line into the guide line receptacle fails, the mast adapter can be moved upwards again along the launching and landing mast before the next attempt.
[0027] The launching and landing mast can be mounted pivotably on a base frame of the base station. As soon as the kite system is free-flying, the launching and landing mast can be pivoted into a position remote from the tether in order to give the tether enough movement space when the kite system is flying along flight paths.
[0028] The invention also relates to a control unit for a kite device, which control unit is designed to actuate the components of the kite device such that the method according to the invention is carried out in an automated process. The control unit is designed to actuate the kite system of the kite device, in an intermediate phase of a launching process in which a guide line extends between a free-flying kite system and a base station, such that the kite system moves along a flight path and such that the tether is guided in a lateral direction in relation to the wind direction until the guide line bears against the tether. The control unit is designed to actuate a mast adapter of a launching and landing mast of the kite device such that a guide line guided in the mast adapter is moved until the guide line lies in a guide line receptacle of the base station, which receptacle is adjacent to the tether. The control unit is designed to emit a control signal in order to separate a distal portion of the guide line from a proximal portion of the guide line. In one embodiment, a triggering mechanism is directly actuated using the control signal. It is also possible to actuate the guide line winch using the control signal such that the guide line winch exerts an increased tensile force and that the separation of the two portions of the guide line is triggered via the increased tensile force.
[0029] The invention also relates to a kite device having a kite system, a control unit and a ground station. The kite system comprises a kite and a pod, wherein the pod is connected to the kite via a bridle. The kite system is coupled to the base station via a tether. The base station comprises a tether winch for retracting the tether. The base station comprises a guide line winch for retracting the guide line. The control unit is designed according to the invention.
[0030] The base station can be a ground station arranged on the ground. The kite device can be designed to generate electrical energy. The kite system can be connected via the tether to a generator / motor so that in a first operating state the generator / motor acts as a generator that is driven by the tether and in a second operating state the generator / motor acts as a motor with which the tether is retracted.
[0031] It is also possible for the base station to be part of a ship so that a drive force for the ship can be generated with the kite system.
[0032] The disclosure includes developments of the method having features that are described in connection with the control unit according to the invention or with the kite device according to the invention. The disclosure includes developments of the control unit and of the kite device having features that are described in connection with the method according to the invention.
[0033] The invention is described by way of example below using advantageous embodiments, with reference to the attached drawings. In the figures: Figure 1: shows a schematic diagram of a kite device according to the invention; Figure 2: shows a schematic diagram of an operating state of the kite device from Figure 1; Figure 3: shows a kite device according to the invention during a phase of a launching process; Figures 4-5: show details of the kite device from Figure 3 in an enlarged diagram; Figures 6-9: show the view according to Figure 3 in intermediate phases of the launching process; Figure 10: shows a schematic diagram of an aspect of the kite device from Figure 3; Figure 11: shows a section along line A-A in Figure 10; Figure 12: shows a schematic diagram of another aspect of the kite device from Figure 3; Figure 13: shows the infeed device from Figure 12 in a different state; Figure 14: shows the view according to Figure 3 in a further phase of the launching process; Figure 15: shows a block diagram of a control unit according to the invention; Figure 16: shows an alternative embodiment of a kite device according to the invention.
[0034] A kite device shown in Figure 1 is designed to generate electrical energy using a kite system 23. The kite system 23 comprises a kite 14, a pod 25, and a bridle 24, via which the kite 14 is connected to the pod 25. The pod 25 is coupled to a base station 16 via a tether 15. The point of the base station 16 at which the tether 15 coming from the pod 25 first touches the base station 16 forms an infeed point 26 of the base station.
[0035] The base station 16 comprises a tether winch 27 (Figure 3) that is coupled to an electrical generator / motor 17. The generator / motor 17 operates as a generator in a first operating state and as a motor in a second operating state. The generator / motor 17 is connected to a public transmission grid 19 via an electrical power train 18 that comprises a converter and a transformer so that either electrical energy generated using the generator / motor 17 can be fed into the transmission grid 19, or the generator / motor 17 can be operated as a motor using electrical energy drawn from the transmission grid 19. The device comprises a control unit 20 that is designed to control the interplay of the components of the device.
[0036] The control unit 20 comprises an antenna 21 so that control signals can be exchanged with the pod 25 via a radio link 22. In particular, control signals are sent from the control unit 20 to the pod 25 in order to control the flying direction of the kite 14. Using the control signals, the length of control lines of the bridle 24 is changed, whereby the flying direction of the kite 14 is influenced.
[0037] In the exemplary embodiment according to Figure 2, the kite 14 is guided along a horizontal figure of eight oriented substantially transversely to the wind direction W. The horizontal figure of eight lies completely within a wind window 29 in which the wind W acts on the kite 14 with a large amount of force. While the kite 14 follows the flying direction, a tensile force is exerted on the tether 15, with which tensile force the generator / motor 17 is driven via the tether winch 27. Using the motor / generator 17, which in this operating state is operated as a generator, the mechanical energy is converted into electrical energy and fed 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 store of the power train 18. Electrical energy can be generated in this way until the length of the tether 15 is exhausted. The tether 15 is then retracted using the motor / generator 17 operated as a motor before electrical energy can be generated again.
[0038] The base station 16 comprises a deflection pulley system 33 via which the tether 15 coming from the pod 25 is deflected in the direction of the tether winch 27. According to Figure 4, the deflection pulley system 33 comprises a structural part 38 that is fixedly connected to a base frame 43 of the base station 16. A deflection pulley 35 is mounted pivotably about an axis 39 in a frame 40. The frame 40 is mounted pivotably on the structural part 38 via a pivot joint 41, wherein the pivot axis 37 coincides with the axis along which the tether 15 extends between the deflection pulley 35 and the tether winch 27. When the kite 14 executes flight patterns as in Figure 2, the frame 40 is pivoted relative to the structural part 38 so that the tether 15 can always run out from the deflection pulley system 33 within the plane of the deflection pulley 35.
[0039] The deflection pulley system 33 comprises an infeed device 34 through which a portion of the tether 15 that leads to the pod 25 runs. The infeed device 34 forms the infeed point 26, i.e., the first point of the base station 16 that the tether 15 coming from the pod 25 touches. The infeed device 34 is held on a pivot arm 36 that is mounted pivotably on the frame 40. The pivot axis about which the pivot arm 36 can be pivoted is identical to the axis 39 about which the deflection pulley 35 rotates. When the kite 14 executes flight patterns as in Figure 2, the pivot arm 36 is pivoted about the axis 39 so that the tether 15 can run through the infeed device 34 without lateral tension.
[0040] During stoppages or still air phases, the kite system 23 is in a stowed state (not shown) in which the kite 14 is accommodated at the base station 16 in a folded-up state. To transfer the kite system 23 into an operating state as in Figures 1 and 2, a launching process is necessary, with which the kite 14 is first brought into a state in which an aerodynamic lift is effective and in which the kite 14 then rises using the aerodynamic lift to a greater height of a few 100 m, for example.
[0041] Figure 3 shows an early phase of the launching process in which an aerodynamic lift is already effective, and therefore the tether 15 between the pod 25 and the base station 16 is held under tension, but in which the kite 14 is still connected to a launching and landing mast 30 of the base station 16 by a guide line 29. To bring the kite system into this state, the base frame 43 of the base station 16 is oriented relative to the wind direction W such that the launching and landing mast 30 is arranged upwind of the deflection pulley system 33. In this way, it is ensured that the kite 14, under the influence of the wind force, pulls the tether 15 in a direction in which the tether 15 does not collide with the launching and landing mast 30. An X-Z plane is spanned by the wind direction W and the vertical direction. A Y direction perpendicular to the X-Z plane corresponds to the lateral direction 42 within the meaning of the invention.
[0042] To allow this orientation to the wind direction W, the base frame 43 of the base station 16 rests on a foundation 44 via a rotating assembly 45. Via the rotating assembly 45, the base frame 43 can be rotated about a vertical axis relative to the foundation 44.
[0043] The launching and landing mast 30 is connected to the base frame 43 of the base station 16 pivotably about a horizontal axis 47. A rail 48 that bears a mast adapter 46 extends along the launching and landing mast 30. The mast adapter 46 can be displaced along the rail 48 with a motor drive 53. The rail 48 extends beyond the axis 47 into the region of the base frame 43 that bears a segment 49 of the rail 48 that is separate from the launching and landing mast 30.
[0044] The guide line 29 coming from the kite 14 runs via the mast adapter 46 into the base station 16. According to Figure 5, the mast adapter 46 comprises a first pulley 50 and a second pulley 51, via which the guide line 29 is deflected such that it runs parallel to the rail 48. The guide line 29 extends along the rail 48 to the base frame 43 of the base station 16, where the other end of the guide line 29 is wound onto a guide line winch 52. The guide line winch 52 can be set in rotation by a motor in order to wind up the guide line 29. The unrolling of the guide line 29 from the guide line winch 52 takes place passively by exertion of a tensile force on the guide line 29.
[0045] Proceeding from the state in Figure 3, it is not possible to pay out the tether 15 further without the guide line 29 following at the same time. With the invention, a sequence of the launching process is proposed in which the guide line 29 is separated so that a proximal portion 31 of the guide line 29 remains at the base station 16 and a distal portion 32 of the guide line 29 can rise upwards with the kite system 23 (Figure 14). For this purpose, the guide line 29 is provided with a coupling 54 via which the proximal portion 31 and the distal portion 32 of the guide line 29 remain connected to one another until an end phase of the launching process.
[0046] Following the phase in Figure 3, the tether 15 is paid out so that the kite 14 rises vertically but still far below its later operating height. With the rising of the kite 14, the guide line 29 is unwound from the guide line winch 52 by a corresponding length. The coupling 54 runs via the two pulleys 50, 51 of the mast adapter 46. This is possible because the diameter of the coupling 54 is not substantially greater than the diameter of the guide line 29.
[0047] In this way, the kite system 23 is brought into a state that is shown in Figure 6. The mast adapter 46 is then moved downwards along the rail 48 into a position shown in Figure 7. The launching and landing mast 30 is pivoted outwards in order to create space for flying movements of the kite 14; see Figure 8. During these steps, the guide line 29 is unwound from the guide line winch 52 and in Figure 8 can have a length between 150 m and 200 m, for example, between the kite 14 and the mast adapter 46. The length of the tether 15 between the pod 25 and the guide line receptacle 34 is smaller than the length of the guide line 29 and can be between 120 m and 170 m, for example. Figures 7 and 8 show the kite device in an intermediate phase 28 within the meaning of the invention, in which a bulge forms in the guide line from the luff to the lee side or upwind to downwind.
[0048] Up to this point in time, the movement of the kite 14 is substantially limited to rising upwards counter to the pulling direction of the tether 15. Proceeding from the state shown in Figure 8, the control unit 20 sends control signals to the pod 25 in order to steer the kite 14 along flight paths at the height predefined by the tether 15. The repeating flight paths can correspond to the pattern of a horizontal figure of eight as shown in Figure 2, for example. The kite 14 is steered along such flight paths by the pod 25 lengthening or shortening the length of individual control lines belonging to the bridle 24.
[0049] The flying movements of the kite 14 cause the tether 15 to execute movements transversely to its longitudinal direction. The movements of the tether 15 can have a component in the wind direction W and a component in the lateral direction 42. For the invention, the movement in the lateral direction 42 is of interest, which movement causes the guide line 29 to come to bear laterally against the tether 15 in the course of a flight path. If, in the phase in which the guide line 29 bears laterally against the tether 15, the mast adapter 46 is moved downwards along the rail 48 and the guide line 29 is optionally additionally retracted, the guide line 29 slides along the tether 15 in the direction of the infeed device 34 (see Figure 9) until the guide line undergoes a defined deflection in the region of the infeed device 34; see reference sign 67 in Figure 9.
[0050] Selected aspects of the infeed device 34 are shown schematically in Figure 10. According to this, a first guide line receptacle 55 and a second guide line receptacle 56 are formed in the infeed device 34. The guide line receptacles 55, 56 extend over the entire extent of the infeed device 34 in relation to the longitudinal direction of the tether 15 and each form an outwardly open depression, i.e., a depression open towards the direction from which the mast adapter comes. A stop 59 is formed in the lower third of each guide line receptacle 55, 56, so that a portion of the guide line receptacles 55, 56 below the stop 59 has a smaller diameter than a portion above the stop 59. The diameter of the guide line receptacles 55, 56 in each case widens towards the upper end. A collar that has a conical outer face 58 and extends around the tether 15 is formed at the upper end of the infeed device 34. A sensor 57 is arranged in the interior of the infeed device 34.
[0051] If the mast adapter 46 is moved downwards along the rail 48 from the state shown in Figure 8, the guide line 29 slides downwards on the tether 15 until the intersection point between the tether and the guide line strikes the infeed device 34. The guide line is guided through the contour 58 of the infeed device into one of the guide line receptacles. If the guide line 29 is then retracted using the guide line winch 52, the guide line 29 in the exemplary embodiment shown is pulled in the longitudinal direction through the first guide line receptacle 55 until the coupling 54 of the guide line 29 strikes the stop 59 of the first guide line receptacle 55.
[0052] Other aspects of the infeed device 34 are shown in schematic form in Figures 12 and 13. According to these, the infeed device 34 comprises a base body 60 that is fixedly connected to the base frame 43 of the base station 16 via the pivot arm 36 of the deflection pulley system 33. A sleeve 65 is accommodated in the base body 60 and is detachably connected to the base body 60 via a locking mechanism 61. The locking mechanism 61 is shown in a locked state in Figure 12, and the locking mechanism 61 is released in Figure 13.
[0053] If the guide line 29 is retracted further from the state shown in Figure 10, in which the coupling 54 of the guide line 29 bears against the stop 59 of the first guide line receptacle 55, pressure is exerted on the locking mechanism 61 via the stop 59, and a spring element of the locking mechanism 61 is compressed. As a result of the compression of the locking mechanism 61, multiple processes in the infeed device 34 are triggered. Within the sleeve 65, a lever 64 is turned, which acts on the coupling 54 so that an upper part 63 of the coupling 54 is separated from a lower part 62 of the coupling 54. The lever 64 has the further effect that the sleeve 65 is braced against the tether 15, therefore the tether 15 can no longer run freely through the sleeve 65. Finally, the locking mechanism 61 itself is released so that the sleeve 65 is no longer locked relative to the base body 60.
[0054] If the tether 15 is then paid out further, the sleeve 65 runs together with the tether 15, the upper part 63 of the coupling 54 and the distal portion 32 of the guide line 29 out of the base body. The further paying out of the tether 15 is then no longer subject to any limitation caused by the guide line 29.
[0055] Figure 14 shows the final phase of the launching process after the sleeve 65 has run out of the base body 60. In this phase, the tether 15 is paid out further until the kite 14 has reached its operating height. This can be followed by the operating phase shown in Figure 2, in which electrical energy is generated using the kite system 23.
[0056] There are uncertainties as to whether the guide line 29 will come to lie on the left side or the right side of the tether 15 upon transitioning between the state in Figure 6 and the state in Figure 7. The diagram in Figures 10-13 proceeds from the assumption that the guide line 29 lies behind the tether 15 in relation to the view in Figure 7. If the guide line 29 slides along the tether 15 on this side, it runs into the first guide line receptacle 55 of the infeed device 34, as shown in Figures 10-13. If the guide line 29 in Figure 7 were to lie in front of the tether 15, the guide line 29 would run into the second guide line receptacle 56 of the infeed device 34.
[0057] When the mast adapter 46 is moved downwards (Figure 9), it is determined using the sensor 57 of the infeed device 34 whether the guide line 29 has come to lie either in the first guide line receptacle 55 or in the second guide line receptacle 56. If this is the case, the launching process can be continued as described.
[0058] If this is not the case, the preceding steps of the launching process must be repeated. For this purpose, the mast adapter 46 is moved back upwards a little into the position according to Figure 7, and the described process is repeated when the tether 15 moves in the opposite lateral direction. The guide line 29 then lies on the other side of the tether 15 and runs into the second guide line receptacle 56 of the infeed device 34 during the described sequence of steps. If things proceed normally, the guide line 29 lies either in the first guide line receptacle 55 or in the second guide line receptacle 56 at the latest after the first repetition of the sequence. This is established using the sensor 57, and the launching process can be continued with the subsequent steps.
[0059] If the guide line 29 does not yet lie in one of the guide line receptacles 55, 56 even on the second approach as a result of exceptional circumstances, for example unfavourable wind conditions, further repetitions can follow until the guide line 29 has been successfully introduced into one of the guide line receptacles 55, 56.
[0060] Figure 15 shows a block diagram of the control system 20, which is designed to actuate the components of the device such that the launching process takes place in an automated sequence. At the start of the launching process, the control unit 20 actuates an actuator of the guide line winch 52 so that the brake of the guide line winch 52 is released. The guide line 29 can then be unwound from the guide line winch 52 as soon as a tensile force acts on the guide line 29. In the next step, the control unit 20 actuates an actuator of the tether winch 27 so that the tether 15 is paid out by a predefined amount. The kite device is thus brought into the state according to Figure 6. In the next step, the control unit 20 actuates the motor drive 53 of the mast adapter 46 so that the mast adapter 46 moves downwards along the rail 48 of the launching and landing mast 30; Figure 7. An actuator (not shown) is actuated in order to pivot the launching and landing mast 30 outwards; Figure 8.
[0061] In the next step, the control unit 20 sends control signals to the pod 25 via the radio link 22 so that the kite 14 is steered along predefined flight paths. A signal is sent from the pod 25 to the control unit 20 as soon as the tether 15 has reached an extreme position in the lateral direction 42 and the lateral movement direction has reversed. After receiving the signal, the control unit 20 actuates the motor drive 53 of the mast adapter 46 so that the mast adapter 46 moves further downwards along the rail 48 until the mast adapter 46 reaches the position shown in Figure 9. If, after the downward movement of the mast adapter 46, the guide line 29 is in one of the two guide line receptacles and is detected there by the sensor 57, the actuator of the guide line winch 52 is actuated so that the guide line winch 52 rotates and retracts the guide line. The guide line winch 52 is configured such that the rotation process stops automatically as soon as either an increased tensile force emanates from the guide line 29 or the guide line 29 has been retracted so far that the coupling 54 can no longer run into the infeed device 34. The control unit 20 then interrogates the sensor 57 as to whether the guide line 29 is in one of the guide line receptacles 55, 56. As soon as the coupling bears against the stop 59 of the guide line receptacle, the control unit 20 can send a control signal to open the locking mechanism 61, as a result of which the sleeve detaches from the base body 60. The locking mechanism 61 of the infeed device 34 is thereby operated, as a result of which the sleeve detaches from the base body 60. The control unit 20 can then send a control signal to the tether winch 27 so that the tether 15 is paid out as far as the desired operating height of the kite.
[0062] If the sensor 57 reports that the guide line 29 is not in any of the guide line receptacles 55, 56, the control unit 20 actuates the motor drive 53 of the mast adapter 46 so that the mast adapter 46 moves back upwards. The control unit repeats the described sequence until the sensor 57 reports that the guide line 29 is in one of the guide line receptacles 55, 56.
[0063] Figure 16 shows an alternative embodiment of the 5 invention in which the kite device according to the invention is used to generate a drive force for a ship 66.
Claims
1. Method for launching a kite system (23), wherein the kite system (23) comprises a kite (14) and a pod (25), wherein the pod (25) is connected to the kite (14) via a bridle(24), and wherein the kite system (23) is coupled to a base station (16) via a tether (15), in which, in anintermediate phase of a launching process, a guide line(29) extends between the free-flying kite system (23) andthe base station (16), such that a part of the guide line(29) which is attached to the base station (16) lies upwindof the tether (15), and a part of the guide line (29)situated between the base station (16) and the kite system (23) lies downwind of the tether (15), comprising the following steps:a. steering the kite system (23) along a flight pathduring the intermediate phase of the launching process, such that the tether (23) is guided in alateral direction (42) in relation to the wind direction (W) until the guide line (29) bears against the tether (15);b. moving the guide line (29), such that the guide line (29) slides downward along the tether (15) until theguide line (29) lies in a guide line receptacle (55,56) of the base station (16), which receptacle isadjacent to the tether (15);c. separating a distal portion (32) of the guide line(29) from a proximal portion (31) of the guide line (29).
2. Method according to Claim 1, wherein, in the intermediatephase of the launching process, a part of the guide line(29) that is attached to the base station (16) lies upwindof the tether (15), and a part of the guide line situatedbetween the base station (16) and the kite system (23) lies downwind of the tether.
3. Method according to Claim 1 or 2, wherein a part of the guide line (29) that lies upwind of the tether (15) ismoved downwards in order to direct the guide line (29) to the guide line receptacle (55, 56) of the base station(16).
4. Method according to one of Claims 1 to 3, wherein the guideline receptacle (55, 56) is part of a deflection pulleysystem (33) via which the tether (15) is deflected.
5. Method according to Claim 4, wherein the deflection pulleysystem (33) comprises a contour (58) with which the guideline (29) is lifted off the tether (15) and directed into the guide line receptacle (55, 56).
6. Method according to Claim 4 or 5, wherein, after the guide line (29) is separated, the proximal portion (31) is held on the deflection pulley system (33).
7. Method according to one of Claims 1 to 6, wherein, after the guide line (29) is separated, the distal portion (32) is held on the tether (15).
8. Method according to one of Claims 4 to 7, wherein a sleeve (65) is detachably connected to the deflection pulley system (33).
9. Method according to one of Claims 1 to 8, wherein the distal portion (32) and the proximal portion (31) of theguide line (29) are connected to one another via acoupling (54), and wherein the coupling (54) is separated after the guide line (29) runs into the guide line receptacle (55, 56).
10. Method according to one of Claims 1 to 9, wherein it isdetermined using a sensor (57) whether the guide line (29)is in the guide line receptacle (55, 56).
11. Method according to one of Claims 1 to 10, wherein thetether (15) is guided in a first lateral direction, and wherein, if the guide line (29) has not been brought tobear against the tether (15), the tether (15) is guided in a second lateral direction opposite the first direction.
12. Method according to one of Claims 1 to 11, wherein the basestation (16) comprises a first guide line receptacle (55) and a second guide line receptacle (56), and wherein thetether (15) is arranged between the first guide linereceptacle (55) and the second guide line receptacle (56).
13. Control unit for a kite device, wherein the control unit isdesigned to actuate the kite system (23) in an intermediatephase (28) of a launching process, in which a guide line (29) extends between a free-flying kite system (23) of thekite device and a base station (16), such that a part ofthe guide line (29) which is attached to the base station(16) lies upwind of the tether (23), and a part of theguide line (29) situated between the base station (16) and the kite system (23) lies downwind of the tether (23), suchthat the kite system (23) moves along a flight path duringthe intermediate phase of the launching process, and suchthat the tether (23) is guided in a lateral direction (42)in relation to the wind direction (W) until the guide line(29) bears against the tether (15); to actuate a mastadapter (46) of a launching and landing mast (30) of the kite device such that a guide line (29) guided in the mastadapter (46) is moved such that the guide line (29) slidesdownward along the tether (15) until the guide line (29) lies in a guide line receptacle (55, 56) of the basestation (16), which receptacle is adjacent to the tether(15); and to emit a control signal in order to separate adistal portion (32) of the guide line (29) from a proximalportion (31) of the guide line (29).
14. Kite device having a kite system (23), a control unit (20)and a base station (16), wherein the kite system (23) comprises a kite (14) and a pod (25), wherein the pod (25)is connected to the kite (14) via a bridle (24), whereinthe kite system (23) is coupled to the base station (16)via a tether (15), wherein the base station (16) comprisesa tether winch (27) for retracting the tether (15), whereinthe base station (16) comprises a guide line winch (52) for retracting the guide line (29), wherein the control unit (20) is designed according to Claim 13.