ROTOR BLADE, ROTOR, AND SYSTEM HAVING ROTOR AND ROTOR BLADE

Abstract

A rotor blade for a rotor having a vertical rotor shaft provides stream induced driving of the rotor in a direction of driving. The rotor blade includes streaming elements that are arranged successively and at a distance in the direction of driving, wherein each streaming element includes a front edge in the direction of driving and a rear edge in the direction of driving. The rear edge and the front edge are each formed such that, when streamed against by a wind component, it transmits a driving force to the rotor in the direction of driving. Furthermore, a rotor has a rotor blade and a system includes the rotor and an electric machine.

Claims

1-14. (canceled)

15: A rotor (100) having a vertical rotor shaft (M) and multiple rotor blades (110, 120, 130) that are arranged equidistantly in the circumferential direction and are of a uniform type, wherein each rotor blade (110, 120, 130) comprises a plurality of streaming elements (111, 112, 113, 114, 115) that are arranged successively and at a distance in the direction of driving (U), wherein each streaming element (111, 112, 113, 114, 115) comprises a front edge (151) in the direction of driving and a rear edge (152) in the direction of driving (152), and wherein each rear edge (152) and each front edge (151)—at least in a main power transmission region (k1)—are each formed such that, when streamed against by a wind component (v1, v2), it transmits a driving force to the rotor (100) in the direction of driving (U), wherein each front edge (151) has a shape that describes a dynamic stream shape of at least a part of the rotor blade, such that the front edge, when the wind component streams against from a direction that is more to the fore than the abeam direction of the rotor blade, transmits the driving force via a dynamic stream effect, typically dynamic lift effect, to the rotor (100), wherein an envelope (160) of the plurality of stream elements (111, 112, 113, 114, 115) having an envelope outer side (168) and an envelope inner side (169) describes the dynamic stream shape of the rotor blade (110, 120, 130), wherein each front edge (151) describes a convex surface in the direction of driving in the main power transmission region (k1) and the rear edge (152) describes a concave surface in the direction of driving in the main power transmission region (k1), wherein the concave surface of the front edge (151) and the convex surface of the rear edge (152) each are continuously curved such that they substantially describe differentiable surfaces at each location, wherein the envelope outer side (168), between the plurality of streaming elements (111, 112, 113, 114, 115), has at each point a constant radial distance (R1, R2), and wherein all rotor blades (110, 120, 130) of the rotor (100) are configured to be of a uniform type.

16: The rotor (100) according to claim 15, wherein all streaming elements (111, 112, 113, 114, 115) of each rotor blade (110, 120, 130) extend, on the envelope outer side (168), with a constant radial distance along the exterior of the rotor.

17: The rotor (100) according to claim 15, wherein the rear edge (152) of each streaming element (111, 112, 113, 114, 115) of each rotor blade (110, 120, 130) comprises a working surface for the wind component (v1) whose surface area is greater than a planar surface through the streaming element (111, 112, 113, 114, 115) in the radial direction.

18: The rotor (100) according to claim 15, wherein the plurality of streaming elements (111, 112, 113, 114, 115) of each rotor blade (110, 120, 130) each comprise a material thickness that rises from the outer and inner ends to the center of the respective streaming element (111, 112, 113, 114, 115).

19: The rotor (100) according to claim 15, wherein the streaming elements (111, 112, 113, 114, 115) of each rotor blade (110, 120, 130) are arranged successively in the direction of driving such that in the circumferential direction between two adjacent streaming elements (111, 112, 113, 114, 115) of a same respective rotor blade (110, 120, 130) a gap having a respective gap width (d1, d2, d3, d4), is formed, wherein the gap width enables an acting of the wind component (v1, v2) between the adjacent streaming elements.

20: The rotor (100) according to claim 19, wherein all adjacent streaming elements (111, 112, 113, 114, 115), of the same respective rotor blade (110, 120, 130) are shaped and have a gap width (d1, d2, d3, d4) such that an obstacle-free straight-aligned passage (175) is formed into a rotor inner region (170).

21: The rotor (100) according to claim 15, wherein all streaming elements (111, 112, 113, 114, 115) of the same rotor blade (110, 120, 130) further comprise a force transmission discontinuation region (k2) having a direction of curvature opposite to the main power transmission region (k1), wherein a transition of the directions of curvature from the main power transmission region (k1) to the force transmission discontinuation region (k2) typically extends, in each point, in a differentiable manner.

22: The rotor (100) according to claim 15, wherein at least one of the following group is adapted to the streaming conditions to be expected during normal operation and/or adapted to a size of the rotor blade: Gap width between two adjacent streaming elements; progression of different gap widths between multiple adjacent streaming elements; progression of different radii of curvature of multiple streaming elements; number of streaming elements per rotor blade.

23: The rotor (100) according to claim 15, wherein the streaming elements (111, 112, 113, 114, 115) of each rotor blade (110, 120, 130) are formed of a metal material.

24: The rotor (100) according claim 15, wherein the number of rotor blades (110, 120, 130) is adapted to the streaming conditions to be expected during normal operation and/or adapted to a size of the rotor blade.

25: A system (10) having a rotor (100) according to claim 15 and an electric machine (200), wherein the rotor shaft (M) of the rotor is mechanically coupled to a machine shaft of the electric machine (200).

26: The system (10) according to claim 25, further comprising a control unit (300) for obtaining a rotational speed of the machine shaft and/or of the rotor shaft and for controlling the electric machine selectively in generator operation and motor operation, wherein the control unit is configured such that it controls the electric machine (200) in the motor operation when the obtained rotational speed falls below a predetermined threshold for a predetermined period.

Description

SHORT DESCRIPTION OF THE DRAWINGS

[0030] FIG. 1 illustrates a sectional view of a rotor having rotor blades according to an embodiment, when the section is taken through the rotor along a plane perpendicular to the axial direction of the rotor.

[0031] FIG. 2 illustrates the sectional view of FIG. 1 with further explanations;

[0032] FIG. 3 illustrates a schematic diagram of a system having a rotor according to an embodiment and having a control unit;

[0033] FIG. 4 illustrates a sectional view along the lines of FIG. 1 and FIG. 2, of a rotor having rotor blades according to an embodiment;

[0034] FIG. 5 illustrates a streaming element having a main power transmission region; and

[0035] FIG. 6 illustrates a streaming element having a main power transmission region and a force transmission discontinuation region.

DESCRIPTION OF EMBODIMENT(S)

[0036] FIG. 1 and FIG. 2 are a sectional view through a rotor 100 along a plane that extends perpendicularly to the direction of a rotor shaft M of the rotor 100. The embodiment shown in FIG. 1 and FIG. 2 is the same, and for reasons of clarity, FIG. 1 and FIG. 2 differ only in the labelling provided for explanation and in the reference signs. The following description thus refers at the same time to FIG. 1 and FIG. 2.

[0037] The rotor shaft M of the rotor 100 defines, at the same time, the direction of the rotational axis, i.e. the axial direction. Fastenings, for example struts (not illustrated), extend in the radial direction R, wherein a first rotor blade 110, a second rotor blade 120 and a third rotor blade 130, respectively, or their respective elements, are fixed, as described further below. It is noted that the number of rotor blades is not limited to three, and may be one, two, four, or more than four. Also, as shown in the embodiment according to FIG. 1, the rotor blades 110, 120, 130 are configured to be of a uniform or similar type. Even though the further description will carry on with this assumption, the configuration of multiple rotor blades 110, 120, 130 is not limited to them being uniform. When reference is made to “the rotor blade 110, 120, 130” in the following, this includes the configuration respectively described of one, multiple or all rotor blades 110, 120, 130.

[0038] The rotor 100 rotates by the arrangement and configuration of the rotor blades 110, 120, 130 always in the rotational direction which is shown in FIG. 1 by an arrow U of the circumferential direction. This rotational direction is the direction of driving and is thus fixed.

[0039] The rotor blade 110, 120, 130 comprises a plurality of streaming elements 111, 112, 113, 114, 115. The number of streaming elements per rotor blade 110, 120, 130 is not limited to five, and less or more than five streaming elements may be provided. The multiple streaming elements 111, 112, 113, 114, 115 of a rotor blade 110, 120, 130 are arranged at a distance to each other in the circumferential direction U, for example at an angular distance α4 between the first or frontmost streaming element 111 and the second streaming element 112 in the rotational direction, an angular distance α3 between the second streaming element 112 and the third streaming element 113, an angular distance α2 between the third streaming element 113 and the fourth streaming element 114, and an angular distance α1 between the fourth streaming element 114 and the fifth streaming element 115. Without limitation and as an example only, for example, α1=8°, α2=11°, α3=11°, and α4=13° applies.

[0040] An abeam direction Q1 is exemplarily shown for the fifth streaming element 115. The abeam direction Q1 is the direction that, from the axial center point of the rotor shaft M, radially intersects a center point of the streaming element 115 (that is, in the direction R). An abeam direction can thus be defined for each streaming element 111, 112, 113, 114, 115.

[0041] The streaming elements 111, 112, 113, 114, 115 are each curved such that they have a front edge, or leading edge, 151 and a rear edge, or trailing edge, 152 in the direction of driving. In the embodiment shown, the streaming elements have a thin material thickness; therefore, the front edge 151 and the rear edge 152 are each spaced apart at a minute distance b that is defined by the material thickness. For example, b<5 cm applies.

[0042] In the embodiment, furthermore, the streaming elements 111, 112, 113, 114, 115 are arranged such that elements adjacent to each other are spaced apart from each other at a distance of a gap d1, d2, d3, d4.

[0043] According to the embodiment, the outer points 161, 162, 163, 164, 165 (and the respectively opposed outer points in the direction of the rotor shaft M) describe, in the sectional plane, a dynamic stream shape or a streamlined shaped 160 that effects an advancing or propulsion in the direction of driving. The streamlined shape 160 is a (conceptual) envelope that would be obtained if the outer points 161, 162, 163, 164, 165 were covered by an elastic skin such that an envelope outer side 168 is obtained, and the elastic skin were continued on the side facing a rotor inner region 170 such that an envelope inner side 169 is obtained. It is noted that the envelope 160 of the envelope outer side 168 and the envelope inner side 169 is not a real element but rather serves for a simplified description in the form of a concept of thinking.

[0044] The envelope outer side 168, between the plurality of stream elements 111, 112, 113, 114, 115, has substantially at each point a constant radial distance R1, R2. The radius of the envelope outer side 168 relating to the center point M of the rotor 100 is thus substantially the same at least at each place between the plurality of streaming elements 111, 112, 113, 114, 115 as well as on their respective outer points 161, 162, 163, 164, 165. Particularly, at least on the envelope outer side, the streaming elements 111, 112, 113, 114, 115 do not run spirally towards the center point M of the rotor 100, but they extend substantially constant on the exterior of the rotor.

[0045] The streaming elements 111, 112, 113, 114, 115 effect, by their shaping, their spacing apart or the gaps inbetween, respectively, that the rear edge 152 and the front edge 151 are each shaped such that when streamed against by a wind component v1, v2, they transmit a driving force to the rotor 100 that acts in the direction of driving.

[0046] For example, FIG. 1 shows a wind component v1 that impacts more abaft than the abeam direction Q1 onto the streaming element 115. At the same time, the wind component v1 also impacts more abaft than abeam onto the further streaming elements 111, 112, 113, 114, 115 belonging to the rotor blade 110. By the spacing apart of the streaming elements 111, 112, 113, 114, 115, the wind component v1 streaming onto the rotor blade 110 can act, through the gaps, on the respective rear edges 152 and push the rotor 100 in the direction of driving.

[0047] In the example in FIG. 2, a wind component v2 is shown that impacts more to the fore than the abeam direction Q1 onto the streaming element 115. At the same time, the wind component v2 also impacts more to the fore than abeam onto the further streaming elements 111, 112, 113, 114, 115 belonging to the rotor blade 110. By the spacing apart of the streaming elements 111, 112, 113, 114, 115, the wind component v2 streaming onto the rotor blade 110 can act, through the gaps, on the respective front edges 151 and, by the dynamic streaming effect, pull the rotor 100 in the direction of driving.

[0048] At the same time, in the example in FIG. 2, the wind component v2 also acts onto the streaming elements as a whole that form the dynamic stream shape 160. Thereby, the efficiency can be further improved.

[0049] FIG. 3 shows a schematic diagram of a system 10 having a rotor 100, an electric machine 200 and a control unit 300. The rotor shaft M is connected, via a connection shaft 250, with a machine shaft (not shown) of the electric machine 200. The connection shaft 250 may also be formed by one of the rotor shaft M and the machine shaft. Furthermore, a control unit is signally connected with the electric machine 200 and configured such that it acquires the rotational speed of the connection shaft 250, the machine shaft and/or the rotor shaft M and controls the electric machine 200 selectively in generator operation and motor operation. When the acquired rotational speed exceeds a predetermined threshold for a predetermined period, the control unit 300 controls the electric machine 200 in the motor operation.

[0050] FIG. 4 illustrates a sectional view along the lines of FIG. 1 and FIG. 2, of a rotor 100 having rotor blades 110, 120, 130 according to the embodiment. The explanations above that have been given in connection with FIGS. 1-3 also apply to FIG. 4, and repeated explanations are omitted here. As apparent from FIG. 4, the streaming elements are formed and spaced apart such that there is an obstacle-free passage along a straight line 175 into the rotor inner region 170. In FIG. 4, this is exemplary shown for the streaming elements 112, 113 of the rotor blade 130; however, this concept is applicable to all streaming elements of all rotor blades. This may contribute to an advantageous utilization of possible swirls or vortexes of the impacting wind component.

[0051] FIG. 5 illustrates a streaming element 211 having a main power transmission region k1 in which an impacting wind component transmits a greater part of its force, for example more than 80%, of the force that is theoretically possible, to the respective streaming element 211. The material thickness of the streaming element 211 increases from the outer points thereof towards the center continuously or steadily, such that substantially a streamlined shape is obtained.

[0052] FIG. 6 illustrates a streaming element 311 having a main power transmission region k1 and a force transmission discontinuation region k2. The transition between the directions of curvature from the main power transmission region k1 to the force transmission discontinuation region k2 extends typically such that is differentiable in each point. Such a force transmission discontinuation region k2 may contribute to further reduce swirls or vortexes of the impacting wind component that disturb the driving and/or to further amplify swirls or vortexes of the impacting wind component that promote the driving.