Wind turbine with switchable clutch for rotary coupling of a power generator

Abstract

Wind turbine (1), comprising: - at least one wing (4) which is moved by wind flow (A, B, C), in particular rotated, and - a drive shaft (5) arranged on the ground side, which is driven by the movement of the at least one wing (4), characterized by several current generators (8) arranged on the ground (7), wherein a coupling (9) which can be switched between two switching positions, in particular electrically controllable, is arranged between at least one of the current generators (8) and the drive shaft (5), which in one switching position rotatably couples the at least one current generator (8) with the drive shaft (5) and in the other switching position does not rotatably couple it with the drive shaft (5).

Description

[0001] The invention relates to a wind turbine with at least one blade which is moved by the wind flow, in particular rotated, and with a drive shaft arranged on the ground which is driven by the movement of the at least one blade.

[0002] Wind turbines convert kinetic energy, such as that from horizontally flowing wind, into electrical energy and feed it into a power grid. The dominant design is a three-bladed rotor mounted at the top of a tall tower, allowing it to rotate around a horizontal axis. A generator is also located at the top of the tower, resulting in high shear forces, material fatigue, high maintenance requirements, a lack of redundancy, and large masses in the nacelle. Typically, the generator and rotor are steered to follow the wind direction by an electric motor. The resulting torque from the rotor is transmitted via a transmission unit, such as a shaft, drum, or cable system, to a drive shaft of the generator.

[0003] The object of the present invention is to distribute the forces occurring in a wind turbine of the type mentioned above as evenly as possible, to reduce material fatigue, to offer redundancy and reliability, and to be able to absorb load peaks.

[0004] This problem is solved according to the invention by several power generators arranged on the ground, wherein a coupling which can be switched between two switching positions, in particular electrically controlled, is arranged between at least one of the power generators and the drive shaft, which in one switching position rotatably couples the at least one power generator with the drive shaft and in the other switching position does not rotatably couple it with the drive shaft.

[0005] According to the invention, the torque generated by the blades can be selectively or as needed distributed among several ground-mounted generators, thereby reducing the load per generator, creating redundancy, and simplifying maintenance. Depending on the available wind or updraft power, only the required number of generators can be operated by selectively switching them on or off. This multiple-generator arrangement reduces the load per generator, increases redundancy, and improves operational reliability. Furthermore, it ensures an even load distribution across multiple generators.

[0006] Overall, the invention enables significant improvements over the prior art, namely: - lower maintenance costs, - longer lifespan, - improved efficiency, - Scalability and modularity, - increased operational reliability.

[0007] In one possible embodiment of the wind turbine according to the invention, at least some of the power generators, in particular all power generators, can each be rotaryally coupled to the drive shaft via their own switchable coupling. The power generators can be rotaryally coupled to the drive shaft as needed. Thus, for example in an emergency, all power generators can also be decoupled from the drive shaft.

[0008] In another possible embodiment of the wind turbine according to the invention, at least one of the generators is permanently rotaryally coupled to the drive shaft, while the other generator(s) can each be rotaryally coupled to the drive shaft via their own switchable coupling. The permanently rotaryally coupled generator can provide the base load of the wind turbine, and the other generators can be switched on as needed.

[0009] In another possible embodiment of the wind turbine according to the invention, a first power generator is permanently rotaryally coupled to the drive shaft or can be rotaryally coupled to the drive shaft via a switchable clutch, wherein at least one further power generator, in particular all other power generators, can be modularly rotaryally coupled to the respective preceding power generator via their own switchable clutch.

[0010] Preferably, a gear stage is arranged between the at least one power generator and the associated switchable clutch in order to be able to provide different speeds at the power generator.

[0011] At least some of the switchable clutches, in particular all switchable clutches, can advantageously be arranged axially one behind the other along the drive shaft, in particular at equidistant intervals, or around the drive shaft, in particular at equidistant angular intervals.

[0012] Particularly preferred are the single or multiple switchable clutches, each designed as an electrically controlled magnetic clutch, e.g., as a magnetic drive with pole-guided transmission, or as a gear clutch. In the former case, load peaks can be absorbed contactlessly by the magnetic clutches. The magnetic clutches and / or the gears of the gear clutch can, for example, be segmented.

[0013] In one possible embodiment, the wind turbine according to the invention has a rotor with several blades rotatably mounted about a horizontal axis of rotation.

[0014] In another possible embodiment, the wind turbine according to the invention has a self-contained drive belt which rotates on an upper deflection element and a lower deflection element, which are rotatably mounted about axes of rotation parallel to each other, in particular horizontal. A plurality of vanes are attached to the drive belt and project outwards beyond the drive belt. Preferably, the vanes have an airfoil profile (air profile) in a cross-sectional plane perpendicular to the normal of the drive belt, in which one side of the airfoil is convexly curved and has a longer flow length, and the opposite side of the airfoil is concavely curved and has a shorter flow length, whereby the drive belt, driven by air flowing in the axial direction of the axes of rotation of the deflection elements, rotates in one direction.

[0015] Further advantages of the invention will become apparent from the description, the claims, and the drawing. The embodiments shown and described are not to be understood as an exhaustive list, but rather serve as examples for illustrating the invention.

[0016] They show: Fig. 1 schematically a wind turbine according to the invention with several ground-side power generators, each of which can be rotatably coupled to a drive shaft by means of its own magnetic coupling; Fig. 2 schematically a second wind turbine according to the invention with several ground-side power generators, each of which can be rotatably coupled to a drive shaft by means of its own magnetic coupling; Fig. 3 the wing cross-section of the in Fig. 2 wings shown along III-III; Fig. 4 schematically the drive shaft of a wind turbine according to the invention with several ground-side power generators, one of which is permanently rotary-coupled to the drive shaft and the other power generators can each be rotary-coupled to the drive shaft by means of their own magnetic coupling; Fig. 5 schematically the drive shaft of a wind turbine according to the invention with several ground-side power generators, of which a first power generator can be rotatably coupled to the drive shaft by means of a magnetic coupling and each subsequent power generator can be rotatably coupled to the respective preceding power generator modularly via a magnetic coupling; Fig. 6 a gear stage arranged between the magnetic coupling and the associated power generator of a wind turbine according to the invention; Fig. 7 several magnetic couplings arranged one after the other along the drive shaft of a wind turbine according to the invention; and Fig. 8 several magnetic couplings arranged around the drive shaft of a wind turbine according to the invention.

[0017] The in Fig. The wind turbine 1 shown comprises a rotor 3 rotatably mounted about a horizontal axis of rotation 2, with several, here three, in particular inclined blades 4 relative to the axis of rotation A, which are rotated by the wind flow (horizontal flows A, B, vertical (updraft) flow C), a drive shaft 5 located at ground level, a transmission unit (e.g. shaft, drum or cable system) 6 which transmits the rotational movement of the rotor 3 into a rotational movement of the drive shaft 5, and several, here only four by way of example, power generators 8 located at ground level 7, which can be driven by the drive shaft 5. Between the drive shaft 5 and the power generators 8, a magnetic coupling 9, which can be switched in two positions and in particular is electrically controlled, is arranged, which in one switching position rotatably couples the respective power generator 8 to the drive shaft 5 and in the other switching position does not rotatably couple it to the drive shaft 5.

[0018] In contrast to the wind turbine of the Fig. 1 are at the in Fig. In the wind turbine 1 shown in Figure 2, the several blades 4 (sixteen by way of example) are not attached to a rotor, but to a closed drive belt 10, which rotates on an upper deflection element (pulley) 11a and a lower deflection element (pulley) 11b, which are rotatably mounted about parallel, here horizontal, axes of rotation 2a, 2b. The blades 4 project outwards beyond the drive belt 10 and are preferably arranged equidistant from each other.

[0019] As seen in the cross-sectional view of the Fig. As shown in Figure 3, the wings 4 can have an airfoil profile (air profile) in a cross-sectional plane E extending perpendicular to the normal of the drive belt 10, in which one wing side 12 - in Fig. 3 the upper surface of the wing - is convexly curved and has a longer flow path and the opposite, other wing side 13 - in Fig. 3 the underside of the wing is concavely curved and has a shorter flow path. This causes the drive belt 10 to rotate in the direction of rotation 14, driven by horizontal airflow B flowing along the wing 4 in the axial direction of the rotation axes 2a, 2b of the two deflection elements 11a, 11b. Furthermore, for rising air in each rotational position of the drive belt 10, the total drag of all elements on one side is reduced. Fig. 2. The existing wings on the right side of the band are 4 greater than the total drag of all wings on the other side. Fig. The 2 left-hand side of the belt has a wing 4, causing the drive belt 10, driven by vertical (updraft) flow C, to rotate in the direction of rotation 14. The lower deflection element 11, if arranged on the ground side, can simultaneously form the drive shaft 5.

[0020] In Fig. 1 and Fig. 2 all power generators 8 are each rotaryally coupled to the drive shaft 5 via their own switchable magnetic coupling 9.

[0021] Fig. Figure 4 shows the drive shaft 5 and several, here four, bottom-mounted power generators 8, at least one of which is in Fig. 4 Only the left one is permanently rotary-coupled to the drive shaft 5. The remaining three generators 8 can each be rotary-coupled to the drive shaft 5 by means of their own magnetic coupling 9.

[0022] Fig. Figure 5 shows the drive shaft 5 and several, here three, bottom-mounted power generators 8, one of which is a power generator 8 in Fig. The left-hand generator 5 can be rotaryally coupled to the drive shaft 5 by means of a magnetic coupling 9. Each subsequent generator 8 can be modularly rotaryally coupled to the preceding generator 8 via a magnetic coupling 9.

[0023] Fig. Figure 6 shows a gear stage 15 arranged between the magnetic coupling 9 and the associated generator 8 in order to be able to provide different speeds at the generator 8.

[0024] Fig. Figure 7 shows several magnetic couplings arranged one behind the other along the drive shaft 5.

[0025] Fig. Figure 8 shows several magnetic couplings 9 arranged concentrically in a planetary arrangement around the drive shaft 5 to distribute the torque of the drive shaft 5 evenly to the power generators 8.

Claims

[1] Wind power plant (1), comprising: - at least one wing (4) which is moved by wind flow (A, B, C), in particular rotated, and - a drive shaft (5) arranged on the ground side, which is driven by the movement of at least one wing (4), characterized by several power generators (8) arranged on the ground (7), wherein a coupling (9) which can be switched between two switching positions, in particular electrically controlled, is arranged between at least one of the power generators (8) and the drive shaft (5), which in one switching position rotatably couples the at least one power generator (8) with the drive shaft (5) and in the other switching position does not rotatably couple it with the drive shaft (5). [2] Wind turbine (1) according to claim 1, characterized by, that at least some of the power generators (8), in particular all power generators (8), are each rotatably coupled to the drive shaft (5) via their own switchable clutch (9). [3] Wind turbine (1) according to claim 1 or 2, characterized by , that at least one of the power generators (8) is permanently rotary-coupled to the drive shaft (5) and the other power generator(s) (8) can each be rotary-coupled to the drive shaft (5) via their own switchable clutch (9). [4] Wind turbine (1) according to claim 1 or 2, characterized by , that a first power generator (8) is permanently rotary-coupled to the drive shaft (5) or can be rotary-coupled to the drive shaft (5) via a switchable clutch (9) and at least one further power generator (8), in particular all other power generators (8), can be modularly rotary-coupled to the respective preceding power generator (8) via their own switchable clutch (9). [5] Wind turbine (1) according to any one of the preceding claims, characterized by , that a gear stage (15) is arranged between the at least one power generator (8) and the associated switchable clutch (9). [6] Wind turbine (1) according to any one of the preceding claims, characterized by , that at least some of the switchable clutches (9), in particular all switchable clutches (9), are arranged axially one behind the other along the drive shaft (5). [7] Wind power plant (1) according to any one of claims 1 to 6, characterized by , that at least some of the switchable clutches (9), in particular all switchable clutches (9), are arranged around the drive shaft (5). [8] Wind turbine (1) according to any one of the preceding claims, characterized by , that the one switchable clutch (9) or the several switchable clutches (9) are each designed as a magnetic clutch or as a toothed clutch. [9] Wind turbine (1) according to any one of the preceding claims, characterized by a rotor (3) rotatably mounted about a horizontal axis of rotation (2) with several blades (4). [10] Wind turbine (1) according to any one of claims 1 to 8, characterized by a self-contained drive belt (10) which runs on an upper deflection element (11a) and a lower deflection element (11b) which are rotatably mounted about parallel, in particular horizontal, axes of rotation (2a, 2b), and by a plurality of wings (4) attached to the drive belt (10) which project outwards beyond the drive belt (10). [11] Wind turbine (1) according to claim 10, characterized by, that the wings (4) have an airfoil profile in a cross-sectional plane (E) perpendicular to the normal of the drive belt (10), whereby the drive belt (10), driven by air (B) flowing in the axial direction of the axes of rotation (2a, 2b) of the two deflection elements (11a, 11b), rotates in a direction of rotation (14).

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