Wind turbine and wind power plant

Abstract

A dual-rotor wind turbine (10) is disclosed that includes a first turbine rotor (36) attached to a first turbine shaft (37) and a second turbine rotor (47) attached to a second turbine shaft (48). The first turbine shaft (37) is rotatable about a rotation axis (A), and the second turbine shaft (48) is rotatable in the opposite direction about the same rotation axis (A). The first turbine rotor (36) includes at least one first turbine blade (38) extending outwardly from the first turbine shaft (37), and the second turbine rotor (47) includes at least one second turbine blade (49) extending outwardly from the second turbine shaft (48). The at least one first turbine blade (38) further forms a first blade angle (40) with respect to the first turbine shaft (37), and the at least one second turbine blade (49) forms a second blade angle (51) with respect to the second turbine shaft (48). The first blade angle (40) and the second blade angle (51) are both acute angles when the wind turbine (10) is operating.

Description

Technical Field

[0001] The present invention relates to a dual-rotating wind turbine comprising at least a first turbine rotor and a second turbine rotor attached in a dual-rotating manner, and a wind power plant comprising a dual-rotating wind turbine comprising at least a first turbine rotor and a second turbine rotor attached in a dual-rotating manner.

Background Art

[0002] Wind power is playing an increasingly important role in the ongoing energy transition towards renewable energy. The worldwide cumulative installed capacity of onshore wind power is estimated to increase by more than threefold by 2030 and could increase sevenfold by 2050, and the installed wind power capacity is expected to increase substantially further globally towards 2050.

[0003] Currently, there are two main wind turbine technologies, classified by the orientation of the axis of rotation of the wind turbine. The three-blade horizontal axis wind turbine (HAWT) with blades above the tower accounts for the overwhelming majority of wind power in the world today. These turbines have a main rotor shaft and a generator at the top of the tower and are directed into the wind. The generator is placed on the shaft of the nacelle. The technology for such wind turbines is mature, and all horizontal turbines manufactured and installed today have a similar design. HAWTs have increased in size and installed capacity over the past few years and are now in the range of 1 MW to 14 MW per turbine. HAWTs have traditionally been installed on land but are now also installed on the seabed of shallow seas.

[0004] A vertical axis wind turbine (VAWT) has a rotational axis that is perpendicular to the wind direction and is typically installed using a rotational axis that is perpendicular to the ground. Thus, this is a type of wind turbine where the main components can be placed at the base of the turbine while the main rotor shaft is set horizontally with respect to the wind. This arrangement allows the generator to be placed close to the ground with a low center of gravity, which is useful for easy access for service and repair. VAWTs do not need to be pointed into the wind, eliminating the need for a mechanism to sense and orient to the wind. However, VAWTs have not received the same level of attention and investment as HAWTs and currently account for less than 0.1% of the installed wind power capacity.

[0005] Existing technologies related to VAWTs have certain drawbacks that can explain the very low attention VAWTs have received so far. First, the efficiency of conventional Savonius VAWT turbines is low compared to HAWTs because they are mainly turbines that rely on drag for their operation and the downstream blades do not contribute to power generation. Smaller Darrieus turbines also experience vibrations from the torque acting on the mast, leading to increased wear and cracking and the need for maintenance. Finally, perhaps most importantly, VAWTs have not received the same level of investment in research and development as HAWTs and are thus a much less mature technology.

[0006] Generally, the problem with existing wind turbines is the gear system that is subject to widely varying forces. Thus, the gear system must be designed to withstand forces that vary greatly over time and is therefore costly. Wind turbines still require extensive maintenance and monitoring to prevent and avoid complete failure of the gears.

[0007] Meteorological conditions are often severe at the locations where wind turbines are installed, and the design of wind turbines must also compensate for the effects of strong winds and the waves for wind turbines installed offshore. Additionally, wind conditions can vary quite a bit depending on how far the wind turbine is mounted from the ground or water surface.

SUMMARY OF THE INVENTION

PROBLEMS TO BE SOLVED BY THE INVENTION

[0008] Accordingly, an object of the present invention is to develop a wind turbine in which at least one, preferably several or all of the above problems are alleviated.

[0009] A further object of the present invention is to develop a wind turbine that can be scaled up to a much larger size than wind turbines installed today.

[0010] A further object of the present invention relates to a wind turbine that can generate substantially more power than wind turbines known today.

[0011] A further object of the present invention is to develop a wind turbine with a generator that does not require a gear system.

[0012] A further object of the present invention is to provide a wind turbine in which the manufacturing, maintenance, and monitoring costs of the gear system of the wind turbine are reduced.

MEANS FOR SOLVING THE PROBLEM

[0013] These objects are met by using the dual-rotating wind turbine defined in claim 1 and the wind power plant defined in claim 27. Further embodiments of the invention are defined in the dependent claims.

[0014] Accordingly, a dual-rotor wind turbine is provided that includes at least a first turbine rotor attached to a first turbine shaft and a second turbine rotor attached to a second turbine shaft. The first turbine shaft is rotatable about a rotation axis (A), the second turbine shaft is rotatable in the opposite direction about the same rotation axis (A), the first turbine rotor includes at least one first turbine blade extending outwardly from the first turbine shaft, and the second turbine rotor includes at least one second turbine blade extending outwardly from the second turbine shaft.

[0015] At least one first turbine blade may form a first blade angle with respect to the first turbine shaft, at least one second turbine blade forms a second blade angle with respect to the second turbine shaft, and both the first blade angle and the second blade angle are acute angles, at least when the wind turbine is operating, and may also be acute angles when not operating in some cases.

[0016] Accordingly, preferably, at least one first turbine blade has a first longitudinal axis that forms the first blade angle with the rotation axis (A) such that the first longitudinal axis forms a conical shape when the at least one first turbine blade is rotating about the rotation axis (A), and / or at least one second turbine blade preferably has a second longitudinal axis that forms the second blade angle with the rotation axis (A) such that the second longitudinal axis forms a conical shape when the at least one second turbine blade is rotating about the rotation axis (A). Accordingly, at least one first turbine blade and at least one second turbine blade preferably sweep their respective conical-shaped regions when they are rotating about the rotation axis (A).

[0017] Therefore, at least one first rotor blade preferably sweeps a conical region when the dual-rotating wind turbine is operating, and / or at least one second rotor blade preferably sweeps the conical region.

[0018] The axis of rotation (A) preferably forms an acute angle with the horizontal plane when the wind turbine is operating. Therefore, the wind turbine has an axis of rotation inclined with respect to the direction of the wind, at least when the wind turbine is operating.

[0019] The first turbine rotor sweeps a first swept region during operation, and the second turbine rotor sweeps a second swept region during operation. Preferably, the first turbine rotor and the second turbine rotor are configured such that the first swept region and the second swept region do not substantially overlap when the axis of rotation (A) is vertical.

[0020] The second turbine shaft is preferably rotatably mounted within the first turbine shaft such that the first turbine shaft and the second turbine shaft are coaxial.

[0021] At least one first turbine blade is attached or attached to the first turbine shaft using a first connecting device, and at least one second turbine blade is attached to the second turbine shaft using a second connecting device.

[0022] The first longitudinal axis of at least one first turbine blade preferably extends from the outer tip of at least one first turbine blade to the center point of the first connecting device, and / or the second longitudinal axis of at least one second turbine blade preferably extends from the outer tip of at least one second turbine blade to the center point of the second connecting device.

[0023] The first connecting device is preferably configured to enable adjustment of the first blade angle, and / or the second connecting device is preferably configured to enable adjustment of the second blade angle.

[0024] The first blade angle and the second blade angle can preferably be adjusted independently of each other or separately.

[0025] The first connecting device is preferably configured to enable adjustment of the pitch of at least one first turbine blade, and / or the second connecting device is preferably configured to enable adjustment of the pitch of at least one first turbine blade.

[0026] The first blade angle and the second blade angle are preferably adjusted depending on each other such that, for example, the first blade angle and the second blade angle become equal after the adjustment.

[0027] The first blade angle can preferably be adjusted to be less than 70 degrees and greater than 20 degrees, and / or the second blade angle can preferably be adjusted to be less than 70 degrees and greater than 20 degrees.

[0028] More preferably, the first blade angle can preferably be adjusted to be less than 50 degrees and greater than 40 degrees, and / or the second blade angle can preferably be adjusted to be less than 50 degrees and greater than 40 degrees.

[0029] At least one first wind turbine blade preferably has an airfoil shape, and / or at least one second wind turbine blade preferably has an airfoil shape.

[0030] The first turbine rotor preferably comprises at least one first support arm attached to the first turbine blade and the first turbine shaft, and the second turbine rotor preferably comprises at least one second support arm attached to the second turbine blade and the second turbine shaft.

[0031] At least one first support arm is preferably attached to the upper side of the first turbine blade and the first turbine shaft, and / or at least one second support arm is preferably attached to the upper side of the second turbine blade and the second turbine shaft. As a result, the first turbine shaft preferably extends until at least one first support arm can be attached.

[0032] The length of at least one first support arm is preferably adjustable so as to be able to adjust the first blade angle, i.e., the angle between at least one first turbine blade and the axis of rotation. At least one first support arm may comprise two or more telescopic sections, for example, to adjust the length of at least one first support arm.

[0033] The length of at least one second support arm is preferably adjustable so as to be able to adjust the second blade angle, i.e., the angle between at least one second turbine blade and the axis of rotation. At least one second support arm may comprise two or more telescopic sections, for example, to adjust the length of at least one second support arm.

[0034] The swept area of the first turbine rotor is preferably 0 to 20% larger than the swept area of the second turbine rotor.

[0035] At least one first support arm is preferably airfoil-shaped, and / or at least one second support arm is preferably airfoil-shaped.

[0036] At least one first support arm and / or at least one second support arm is provided with a motion damper device. Preferably, the motion damper device is configured to be able to attenuate / reduce impact and / or vibration.

[0037] The first support arm preferably forms an angle of less than 135 degrees and greater than 45 degrees with respect to at least one first turbine blade, and / or the second support arm preferably forms an angle of less than 135 degrees and greater than 45 degrees with respect to at least one second turbine blade.

[0038] More preferably, the first support arm preferably forms an angle of less than 120 degrees and greater than 70 degrees with respect to at least one first turbine blade, and / or the second support arm preferably forms an angle of less than 120 degrees and greater than 70 degrees with respect to at least one second turbine blade.

[0039] At least one first turbine blade is preferably provided with a first winglet attached to the tip portion of at least one first turbine blade, and / or at least one second turbine blade is preferably provided with a second winglet attached to the tip portion of at least one second turbine blade.

[0040] The first winglet is preferably arranged substantially perpendicular to the longitudinal axis of at least one first turbine blade, and / or the second winglet is preferably arranged substantially perpendicular to the longitudinal axis of at least one second turbine blade.

[0041] The first winglet can be attached with its concave surface facing the first turbine blade or with its concave surface facing outward from the first turbine blade. Similarly, the second winglet can be attached with its concave surface facing the second turbine blade or with its concave surface facing outward from the second turbine blade.

[0042] The first winglet is preferably adjustably attached to at least one first turbine blade and / or the second winglet is preferably adjustably attached to at least one second turbine blade.

[0043] The first winglet is preferably airfoil-shaped and / or the second winglet is preferably airfoil-shaped.

[0044] The length of at least one first turbine blade is preferably greater than the diameter of the first turbine shaft and / or the length of at least one second turbine blade is preferably greater than the diameter of the second turbine shaft.

[0045] The length of at least one first turbine blade is preferably substantially greater than the diameter of the first turbine shaft and / or the length of at least one second turbine blade is preferably substantially greater than the diameter of the second turbine shaft.

[0046] At least one first turbine blade preferably comprises a plurality of first blade segments connected or attached to each other and / or at least one second turbine blade preferably comprises a plurality of second blade segments connected or attached to each other.

[0047] Two adjacent first blade segments are preferably attached to each other at an angle such as to form a non-linear first turbine blade and / or two adjacent second blade segments are preferably attached to each other at an angle such as to form a non-linear second turbine blade.

[0048] At least one pair of adjacent first blade segments are preferably attached to each other in an articulated manner, and / or at least one pair of two adjacent second blade segments are preferably attached to each other in an articulated manner.

[0049] At least one first blade segment is preferably attached to at least one first support arm, and / or at least one second blade segment is preferably attached to at least one second support arm.

[0050] At least a part of at least one first turbine blade may be curved upward or downward with respect to the direction of the rotation axis (A), and / or at least a part of at least one second turbine blade may be curved upward or downward with respect to the direction of the rotation axis (A).

[0051] At least a part of at least one first turbine blade may be curved forward or backward with respect to the rotation direction of the first turbine rotor, and / or at least a part of at least one second turbine blade may be curved forward or backward with respect to the rotation direction of the second turbine rotor.

[0052] At least one first turbine blade may be at least partially curved in the circumferential direction around the first turbine shaft, and / or at least one second turbine blade may be at least partially curved in the circumferential direction around the second turbine shaft.

[0053] There is also provided a wind power plant comprising a double-reversal wind turbine that does not include any of the above additional features, one of the above additional features, some of the above additional features, or all of the above additional features.

[0054] The wind power plant preferably comprises a generator driven by a double-reversal wind turbine.

[0055] The generator is preferably a synchronous generator.

[0056] More preferably, the generator is preferably a permanent magnet synchronous generator. The permanent magnet synchronous generator may include, for example, a neodymium iron magnet or a ferrite magnet.

[0057] The armature winding preferably comprises a high voltage cable.

[0058] The first turbine shaft is preferably attached to the stator portion of the generator, and the second turbine shaft is preferably attached to the rotor portion of the generator.

[0059] The stator portion may be defined as part of a generator with an armature winding.

[0060] The stator portion on the rotating first turbine shaft preferably comprises a rectifier so that a direct current can be transmitted through a rotary contact. The rotary contact may comprise, for example, a slip ring or a liquid metal contact.

[0061] The generator is preferably dimensioned to withstand a load up to 1 to 5 times, preferably 2 to 3 times its rated power. This enables the operation control of the first and second wind turbines even under rough weather conditions.

[0062] The rectifier is preferably configured for active rectification or rectification using diodes.

[0063] The absorption of the effects of the first wind turbine and / or the second wind turbine can preferably be controlled by controlling the rotational speed of the first and / or second wind turbines, i.e., stall control, through the torque of the generator, which can be controlled by active rectification or passive rectification by selecting the voltage level on the DC side of the rectifier.

[0064] The stator part preferably comprises a first stator part and a second stator part. The first stator part is preferably non-rotatable, and the second stator part is preferably rotatable.

[0065] The non-rotatable first stator part is attached to the tower section of the wind power plant, and the rotatable second stator part is attached to the first turbine shaft.

[0066] The stationary first stator part is preferably configured to be used as a motor capable of applying torque to the second turbine shaft.

[0067] During operation, the dual-rotating turbine is preferably configured such that the axis of rotation (A) is inclined with respect to the horizontal plane.

[0068] The wind power plant is preferably configured such that during operation, at least one first turbine blade forms a first blade angle with the axis of rotation (A) that is substantially equal to the inclination of the axis of rotation (A) with respect to the horizontal plane, and / or at least one second turbine blade forms a second blade angle with the axis of rotation (A) that is substantially equal to the inclination of the axis of rotation (A) with respect to the horizontal plane.

[0069] At least one first turbine blade may be arranged such that it is substantially vertical when the tip of the first blade is at the highest position of its rotation path.

[0070] At least one second turbine blade may be arranged such that the second turbine rotor is substantially vertical when the tip of the second blade is at the highest position of its rotation path.

[0071] The wind power plant may be an onshore wind power plant.

[0072] The wind power plant may also be a floating wind power plant, i.e., a wind power plant adapted to be floatingly arranged in a body of water.

[0073] The wind power plant preferably comprises at least one underwater wing arranged to be below the water surface of the body of water, and the at least one underwater wing is adjustable to provide a desired moment to the wind power plant when there is a water current in the body of water.

[0074] The tower of the wind power plant is preferably attached to a fixing system.

[0075] The fixing system is preferably configured to absorb any torque generated by the generator.

[0076] The generator can be configured to be used as a motor that can apply torque between a first turbine shaft and a second turbine shaft. Thereby, it becomes possible to use the generator as a motor for starting the rotation of the first and second turbine rotors.

[0077] The tower preferably comprises at least one buoyancy unit and / or ballast unit.

[0078] The tower is preferably made of steel, aluminum, wood, or a combination of these materials.

[0079] The buoyancy unit and / or ballast unit and / or generator housing are preferably made of steel or concrete or a combination of steel and concrete.

[0080] The first turbine shaft and / or the second turbine shaft are preferably made of steel, aluminum, wood, or a combination of these materials.

[0081] At least one first turbine blade and / or second turbine blade and / or first turbine shaft and / or second turbine shaft is preferably made of a composite material, steel, aluminum, wood, or a combination of these materials.

[0082] The joints connecting the first and second support arms to the first and second turbine blades and the first and second turbine shafts preferably have rotational freedom in at least one dimension so that bending moments are not transmitted by the joints.

[0083] All bearings of the wind power plant are preferably equipped with a monitoring system that enables remote monitoring of the bearing condition.

[0084] The dual-rotating wind turbine is preferably equipped with supervisory control and data acquisition (SCADA).

[0085] The fixed platform mooring and power take-off cable connection are preferably attached to the lower end of the second turbine shaft. The fixed platform may have a hydrodynamic damping plate to enhance rotational stability and reduce torque fluctuations from the mooring system.

[0086] The power cable connected to the platform mooring is preferably connected to a connection point for power transmission to an undersea ocean floor substation or the shore.

[0087] The tower preferably comprises at least one buoyancy unit and / or, preferably, a ballast unit.

[0088] The tower preferably comprises a buoyancy unit adapted to be disposed on the surface of the body of water in which the wind power plant is located.

[0089] The lower part of the tower preferably comprises a nacelle containing a ballast unit. Thus, the ballast unit can form part of the nacelle of a wind power plant.

[0090] The nacelle can further be provided with hydrodynamic wings on the outside. The wings can be controlled to provide a stabilizing effect to the wind power plant.

[0091] The mooring system is preferably rotatably attached to the ballast unit using a turret, for example, although other attachment means can also be used for attaching the mooring system to the wind power plant.

[0092] Non-limiting embodiments of the present invention will be described with reference to the accompanying drawings.

Brief Description of the Drawings

[0093]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

DETAILED DESCRIPTION OF THE INVENTION

[0094] In FIGS. 1 to 10, there is shown an embodiment of a wind turbine 10 according to the present invention, which is also according to the present invention and is arranged in a wind power plant 11.

[0095] FIG. 1 shows a wind power plant 11 equipped with a wind turbine 19. The wind power plant 11 shown in the figure is a semi-submersible wind power plant that floats on a water area with a surface 65.

[0096] The wind power plant 11 includes a first turbine rotor 36 and a second turbine rotor 47. The first turbine rotor 36 includes at least one first turbine blade 38, but preferably includes a plurality of first turbine blades 38 as shown in the figure. The first turbine blade 38 is attached to a first turbine shaft 37. The first turbine shaft 37 is rotatable about a rotation axis A.

[0097] The second turbine rotor 47 includes at least one second turbine blade 49, and preferably includes a plurality of second turbine blades 49 as shown in the figure. The second turbine blade 49 is attached to the second turbine shaft 48. The second turbine shaft 48 is rotatable about the same axis of rotation A.

[0098] As shown in FIG. 6, the first turbine blade 38 and the second turbine blade 49 may be provided with respective first winglets 43 and second winglets 54 attached to the first blade tip 39 and the second blade tip 50, respectively.

[0099] The first turbine rotor 36 and the second turbine rotor 47 are arranged to rotate in a double reverse manner. Therefore, they are coaxial and rotate in opposite directions about the same axis of rotation A.

[0100] When the wind power plant 11 includes the tower 30. When the wind power plant 11 is operating, the tower 30, and thus the axis of rotation A, are arranged such that the tower 30 and the axis of rotation A are inclined with respect to the horizontal plane as shown in the figure.

[0101] As shown in the figure, the first turbine shaft 37 can be considered to form at least a part of the upper part 32 of the tower 30 of the wind power plant 11.

[0102] The lower part 31 of the tower 30 includes a buoyancy unit 12. The buoyancy unit 12 can be arranged to partially sink into the water as shown in the figure. The buoyancy unit 12 can also be arranged to completely sink into the water.

[0103] The lower part 31 of the tower 30 further includes a nacelle 14. The generator 17 of the wind power plant 11 is driven by the double-reversing first turbine shaft 37 and second turbine shaft 48 of the wind turbine 10 and is arranged in the nacelle 14.

[0104] As shown in FIG. 8, the generator 17 includes a stator portion 18 attached to the second turbine rotor 48 and a rotor portion 19 attached to the first turbine rotor 37, i.e., the nacelle 14. The generator 17 is preferably a permanent magnet synchronous generator. The rotor portion 19 of the generator 17 may include, for example, neodymium iron magnets or ferrite magnets, and the stator portion 18 of the generator 17 preferably includes an armature winding with a high voltage cable.

[0105] The generator 17 generates electric power that can be exported to an external consumer or an external energy storage facility through at least one export cable 20.

[0106] The lower part 31 of the tower 30 is preferably firmly attached to the upper part 32 of the tower 30 using a connecting device 34. The connecting device 34 may be, for example, a conventional flange connection in which each flange provided on the lower part 31 and the upper part 32 of the tower 30 is bolted together with an appropriate number of bolts as shown in FIG. 8. Thereby, the lower part 31 and the upper part 32 of the tower 30 are non-rotatably connected, and the lower part 31 and the upper part 32 of the tower 30 rotate together when the wind power plant 11 is operating.

[0107] The second turbine shaft 48 enters the nacelle 14 through the buoyancy unit 12 and is rotatably supported by the tower 30 by a plurality of bearing devices 27. Such bearing devices 27 are shown in FIGS. 6 and 8. Therefore, the second turbine shaft 48 is rotatable with respect to the tower 30 including the buoyancy unit 12 and the nacelle 14.

[0108] At the lower ends of the tower 30 and the nacelle 14, a mooring device 22 with a mooring line connector 23 is provided. The mooring line connector 23 is rotatably supported by a bearing device 24 arranged in the nacelle 14 as shown in FIG. 8. The mooring line connector 23 is designed to allow relative movement between the mooring line connector 23 and the nacelle 14. The mooring line connector 23 can be, for example, a turret that allows relative rotation between the turret and the nacelle 14.

[0109] The mooring device 22 further includes at least one, but preferably a plurality of, mooring lines 25 that are attached at one end to the mooring line connector 23 and, for example, at the other end to the seabed. The mooring system 22 is preferably of a well-known design used, for example, for the fixation of semi-submersible vessels and will not be further described here.

[0110] One or more ballast units 15 are preferably provided in the lower part 31 of the tower 30 as shown in FIG. 8. The ballast unit 15 can be a ballast tank for water so that the amount of additional weight in the lower part 31 of the tower 30 can be adjusted. Alternatively, the ballast unit can be a solid weight, for example, made of steel or iron, arranged in the nacelle 14. The ballast unit may also comprise a combination of a ballast tank and a solid weight.

[0111] As shown in FIGS. 9 and 10, the first turbine blade 38 and the second turbine blade 49 are provided with at least one, preferably a plurality of, connecting arms 57, for example, two connecting arms 57 as shown in the figures. The connecting arm 57 can be an integral part of the first turbine blade 38 and the second turbine blade 49 as shown in the figures. Alternatively, the connecting arm 57 can be a separate part that is firmly fastened to the first turbine blade 38 and the second turbine blade 49 using appropriate fastening means.

[0112] At the end of the connection arm 57, a blade connector 61 is provided. The blade connector 61 can be an integral part of the first turbine blade 38 and the second turbine blade 49. Alternatively, the blade connector 61 can be a separate component that is firmly fastened to the connection arm 57 using appropriate fastening means. The blade connector 61 is provided with bolt holes 62 as shown in FIG. 9.

[0113] The first turbine shaft 38 and the second turbine shaft 49 are provided with bolt connectors 58 that are firmly attached to the first turbine shaft 38 and the second turbine shaft 49, for example, by welding. The bolt connector 58 is provided with bolt holes corresponding to the bolt holes 62 of the blade connector 61, and the bolt 60 is disposed so as to penetrate through the bolt holes of the bolt connector 58 and the bolt holes 62 of the blade connector 61. Thereby, the first turbine blade 38 and the second turbine blade 49 are rotatably connected to the first turbine shaft 37 and the second turbine shaft 48, respectively, which are rotatable about the bolt 60.

[0114] The first turbine rotor 36 is preferably provided with at least one first support arm 41. The number of support arms 41 is usually the same as the number of the first turbine blades 38. The length of the first support arm 41 may be adjustable or may be fixed.

[0115] The first support arm 41 can have one end rotatably attached to the first turbine blade 38 and the other end rotatably attached to the first turbine shaft 37. Further, as shown in FIG. 7, the first support arm 41 may include a first telescopic section 44 and a second telescopic section 45. Thereby, a first blade angle 40 (see FIG. 3), which is an angle between the first turbine blade 38 and the first turbine shaft 37, can be adjusted. Alternatively, the first support arm 41 may be slidably attached at one end to either the first turbine blade 38 or, more preferably, the first turbine shaft 37 in order to adjust the angle between the first turbine blade 38 and the first turbine shaft 37. Thereby, the inclination of the first turbine blade 38 with respect to the first turbine shaft 37 is adjustable, but adjustable such that the first blade angle 40 is an acute angle.

[0116] Similarly, the second turbine rotor 47 is preferably provided with at least one second support arm 52. The number of the second support arms 52 is usually the same as the number of the second turbine blades 49. The length of the second support arm 52 may be adjustable or fixed.

[0117] The second support arm 52 can have one end rotatably attached to the second turbine blade 49 and the other end rotatably attached to the second turbine shaft 48. Further, the second support arm 52 may include a first telescopic section 44 and a second telescopic section 45, as shown in FIG. 7. Thereby, the second blade angle 51 (see FIG. 3), which is the angle between the second turbine blade 49 and the second turbine shaft 48, can be adjusted. Alternatively, the second support arm 52 may be slidably attached at one end to either the second turbine blade 49 or, more preferably, the second turbine shaft 48 to adjust the angle between the second turbine blade 49 and the second turbine shaft 48. Thereby, the inclination of the second turbine blade 49 with respect to the second turbine shaft 48 is adjustable, but adjustable such that the second blade angle 51 is an acute angle.

[0118] In FIG. 3, the inclination of the first turbine blade 38 with respect to the first turbine shaft 37 (and the axis of rotation A) is between 40 degrees and 50 degrees, more precisely about 45 degrees. The inclination of the second turbine blade 49 with respect to the second turbine shaft 48 (and the axis of rotation A) is also between 40 degrees and 50 degrees, more precisely about 45 degrees.

[0119] Furthermore, the inclination of the tower 30 and the axis of rotation A with respect to the horizontal plane and thus with respect to the surface 65 of the water is between 40 degrees and 50 degrees, more precisely about 45 degrees.

[0120] When the first blade angle 40 is approximately the same as the inclination of the axis of rotation A with respect to the horizontal plane, the first turbine blade 38 is in a substantially horizontal position when the first blade tips 39 are in their lowest positions. Thereby, the possibility that the first turbine blade 38 collides with the water is reduced. At the same time, the first turbine blade 38 is in a substantially vertical position when the first blade tips 39 are in their highest vertical positions and an optimal sweep area is obtained.

[0121] When the second blade angle 51 is approximately the same as the inclination of the rotation axis A with respect to the horizontal plane, the second turbine blade 49 is also in a substantially horizontal position when the second blade tips 50 are in their lowest positions. At the same time, when the second blade tips 50 are in their highest vertical positions and an optimal sweep area is obtained, the second turbine blade 49 is in a substantially vertical position.

[0122] When the first turbine rotor 36 and the second turbine rotor 47 rotate, the first turbine blade 38 and the second turbine blade sweep a conical-shaped area 67 as shown in FIG. 5. The sweep area 68 swept by the first rotor blade 38 and the sweep area 69 swept by the second rotor blade have an elliptical shape in vertical projection as shown in FIG. 4.

[0123] As shown in FIG. 6, the first support arm 41 and the second support arm 52 may be either straight or curved.

[0124] The first turbine rotor 36 may further include, for example, a first support strut 42 when the first blade angle 40 is fixed and adjustment of the inclination of the first turbine blade 38 with respect to the first turbine shaft 38 is not possible. The first support strut is attached to the first turbine blade 38 at one end and to the first turbine shaft 37 at the other end.

[0125] The second turbine rotor 47 may further include, for example, a second support strut 53 when the second blade angle 51 is fixed and adjustment of the inclination of the second turbine blade 49 with respect to the second turbine shaft 48 is not possible. The second support strut 53 is attached to the second turbine blade 49 at one end and to the second turbine shaft 48 at the other end.

[0126] Reference numerals used in the description of the drawings:

Table 1

Claims

1. A dual-rotating wind turbine comprising a first turbine rotor attached to a first turbine shaft and a second turbine rotor attached to a second turbine shaft, wherein the first turbine shaft is rotatable about a rotation axis (A), the second turbine shaft is rotatable in the opposite direction about the same rotation axis (A), the first turbine rotor comprises at least one first turbine blade extending outwardly from the first turbine shaft, the second turbine rotor comprises at least one second turbine blade extending outwardly from the second turbine shaft, the at least one first turbine blade forms a first blade angle with respect to the first turbine shaft, the at least one second turbine blade forms a second blade angle with respect to the second turbine shaft, and both the first blade angle and the second blade angle are acute angles when the wind turbine is operating, the dual-rotating wind turbine.

2. The rotation axis (A) forms an acute angle with the horizontal plane when the wind turbine is operating. The dual-rotating wind turbine according to claim 1.

3. The at least one first turbine blade and the at least one second turbine blade sweep respective conical-shaped regions when they are rotating about the rotation axis (A). The dual-rotating wind turbine according to claim 1 or 2.

4. The first turbine rotor sweeps a first swept area during operation, the second turbine rotor sweeps a second swept area during operation, and the first turbine rotor and the second turbine rotor are configured such that the first swept area and the second swept area do not substantially overlap when the rotation axis (A) is vertical. The dual-rotating wind turbine according to claim 1 or 2.

5. The at least one second turbine blade and the at least one second turbine blade are arranged such that the at least one first turbine blade and the at least one second turbine rotor are substantially perpendicular when the second blade tip is at the highest position in the vertical direction of its rotation path. The dual-rotating wind turbine according to any one of claims 1 to 4.

6. The at least one first turbine blade is attached or mounted to the first turbine shaft using a first connecting device, and the at least one second turbine blade is attached to the second turbine shaft using a second connecting device. The dual-reverse wind turbine according to any one of claims 1 to 5.

7. The first connecting device is configured to enable adjustment of the first blade angle, and / or the second connecting device is configured to enable adjustment of the second blade angle. The dual-reverse wind turbine according to any one of claims 1 to 6.

8. The first blade angle and the second blade angle are adjustable independently of each other. The dual-reverse wind turbine according to any one of claims 1 to 7.

9. The first blade angle can be adjusted to be less than 70 degrees and greater than 20 degrees, and / or the second blade angle can be adjusted to be less than 70 degrees and greater than 20 degrees. The dual-reverse wind turbine according to any one of claims 1 to 8.

10. The first blade angle can be adjusted to be less than 50 degrees and greater than 40 degrees, and / or the second blade angle can be adjusted to be less than 50 degrees and greater than 40 degrees. The dual-reverse wind turbine according to any one of claims 1 to 9.

11. The at least one first wind turbine blade has an airfoil shape, and / or the at least one second wind turbine blade has an airfoil shape. The dual-reverse wind turbine according to any one of claims 1 to 10.

12. The first turbine rotor includes at least one first support arm attached to the first turbine blade and the first turbine shaft, and the second turbine rotor includes at least one second support arm attached to the second turbine blade and the second turbine shaft. The dual-reverse wind turbine according to any one of claims 1 to 11.

13. The swept area of the first turbine rotor is 0 to 20% larger than the swept area of the second turbine rotor. The dual-reverse wind turbine according to any one of claims 1 to 12.

14. The at least one first support arm is in the shape of an airfoil section and / or the at least one second support arm is in the shape of an airfoil section. The dual-reversal wind turbine according to any one of claims 1 to 13.

15. A motion damper device is provided on the at least one first support arm and / or the at least one second support arm. The dual-reversal wind turbine according to any one of claims 1 to 14.

16. The at least one first turbine blade is provided with a first winglet attached to the tip portion of the at least one first turbine blade, and / or the at least one second turbine blade is provided with a second winglet attached to the tip portion of the at least one second turbine blade. The dual-reversal wind turbine according to any one of claims 1 to 15.

17. The first winglet is adjustably attached to the at least one first turbine blade, and / or the second winglet is adjustably attached to the at least one second turbine blade. The dual-reversal wind turbine according to claim 16.

18. The first winglet is in the shape of an airfoil section and / or the second winglet is in the shape of an airfoil section. The dual-reversal wind turbine according to claim 16 or 17.

19. The length of the at least one first turbine blade is greater than the diameter of the first turbine shaft, and / or the length of the at least one second turbine blade is greater than the diameter of the second turbine shaft. The dual-reversal wind turbine according to any one of claims 1 to 18.

20. The at least one first turbine blade comprises a plurality of first blade segments connected or attached to each other, and / or the at least one second turbine blade comprises a plurality of second blade segments connected or attached to each other. The dual-reversal wind turbine according to any one of claims 1 to 19.

21. Two adjacent first blade segments are attached to each other at an angle such as to form a non-linear first turbine blade, and / or two adjacent second blade segments are attached to each other at an angle such as to form a non-linear second turbine blade. The dual-reversal wind turbine according to claim 20.

22. At least one pair of adjacent first blade segments are articulated to each other, and / or two adjacent second blade segments are articulated to each other. The dual-reversal wind turbine according to claim 20 or 21.

23. At least one first blade segment is attached to the at least one first support arm, and / or at least one second blade segment is attached to the at least one second support arm. The dual-reversal wind turbine according to any one of claims 20 to 22.

24. At least a part of the at least one first turbine blade is curved upward or downward with respect to the direction of the rotation axis (A), and / or at least a part of the at least one second turbine blade is curved upward or downward with respect to the direction of the rotation axis (A). The dual-reversal wind turbine according to any one of claims 1 to 23.

25. At least a part of the at least one first turbine blade is curved forward or backward with respect to the rotation direction of the first turbine rotor, and / or at least a part of the at least one second turbine blade is curved forward or backward with respect to the rotation direction of the second turbine rotor. The dual-reversal wind turbine according to any one of claims 1 to 24.

26. The at least one first turbine blade is at least partially curved in the circumferential direction around the first turbine shaft, and / or the at least one second turbine blade is at least partially curved in the circumferential direction around the second turbine shaft. The dual-reversal wind turbine according to any one of claims 1 to 25.

27. A wind power plant comprising the dual-reversal wind turbine according to any one of claims 1 to 26.

28. Comprising a generator driven by the dual-reversal wind turbine. The wind power plant according to claim 27.

29. The first turbine shaft is attached to the stator portion of the generator, and the second turbine shaft is attached to the rotor portion of the generator. The wind power plant according to claim 27 or 28.

30. The stator portion on the rotating first turbine shaft includes a rectifier so that direct current can be transmitted through the rotating contact. The wind power plant according to any one of claims 27 to 29.

31. The rectifier is configured for active rectification or rectification using diodes. The wind power plant according to claim 30.

32. The stator portion includes a first stator portion and a second stator portion. The first stator portion is non-rotatable, and the second stator portion is rotatable. The wind power plant according to any one of claims 27 to 31.

33. The non-rotatable first stator portion is attached to the tower of the wind power plant, and the rotatable second stator portion is attached to the first turbine shaft. The wind power plant according to claim 32.

34. The stationary first stator portion is configured to be usable as a motor capable of applying torque to the second turbine shaft. The wind power plant according to claim 33.

35. During operation, the dual-rotating turbine is configured such that the rotating shaft (A) is inclined with respect to the horizontal plane. The wind power plant according to any one of claims 27 to 34.

36. During operation, the wind power plant is configured such that at least one first turbine blade forms a first blade angle with the rotating shaft (A) that is substantially equal to the inclination of the rotating shaft (A) with respect to the horizontal plane, and / or at least one second turbine blade forms a second blade angle with the rotating shaft (A) that is substantially equal to the inclination of the rotating shaft (A) with respect to the horizontal plane. The wind power plant according to any one of claims 27 to 35.

37. The wind power plant includes a tower, and the tower is at least partially formed by the first turbine shaft. The wind power plant according to any one of claims 27 to 36.

38. The wind power plant is a floating wind power plant adapted to be arranged in a body of water. The wind power plant according to any one of claims 27 to 37.

39. The tower section is attached to a fixing system. The wind power plant according to any one of claims 27 to 38.

40. The fixing system is configured to absorb any torque generated by the generator. The wind power plant according to any one of claims 24 to 36.

41. The tower comprises at least one buoyancy unit and / or a ballast unit. The wind power plant according to any one of claims 27 to 40.

42. The tower comprises a buoyancy unit adapted to be arranged on the surface of the body of water in which the wind power plant is arranged. The wind power plant according to claim 41.

43. The lower part of the tower comprises a ballast unit. The wind power plant according to claim 41 or 42.

44. The mooring system is rotatably attached to the ballast unit. The wind power plant according to claim 43.

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