Blade, wind power generation device, and manufacturing method for blade

Abstract

To restrain ice, etc. from adhering to a blade.SOLUTION: A blade is used in such a manner that one end is connected to a rotating shaft, and comprises: a first edge located on the side where a wind flows in during rotation; a second edge located on the side where the wind flows out during the rotation; a first side that is a surface connecting the first edge and the second edge; and a second side that is a surface connecting the first edge and the second edge, and located on the side opposite to the first side. A surface structure in a portion of the first edge is different from that in the other portions of the first edge.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a blade, a wind power generation device, and a method for manufacturing a blade.

Background Art

[0002] Wind power generation devices are being installed in various locations in order to obtain clean energy. For example, wind power generation devices are also installed in cold regions (Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a wind power generation device installed in a cold region, ice or the like may adhere to the blade, which may cause a decrease in power generation efficiency or blade damage.

[0005] An object of the present disclosure is to provide a technique for suppressing the adhesion of ice or the like to a blade.

Means for Solving the Problems

[0006] The blade according to the present disclosure is a blade having one end connected to a rotation axis and used, and includes a first edge on the side where wind flows in during rotation, a second edge on the side where wind flows out during rotation, a first side that is a surface connecting the first edge and the second edge, and a second side that is a surface opposite to the first side and connecting the first edge and the second edge, and a part of the surface structure of the first edge is different from other parts of the first edge.

[0007] The wind power generation device according to the present disclosure includes the above blade.

[0008] The manufacturing method of the blade according to the present disclosure is a construction method of a blade used with one end connected to a rotating shaft. The blade includes a first edge on the side where wind flows in during rotation, a second edge on the side where wind flows out during rotation, a first side which is a plane connecting the first edge and the second edge, and a second side which is a plane opposite to the first side and connecting the first edge and the second edge. The surface structure of a part of the first edge is processed to be different from that of other parts of the first edge.

Advantages of the Invention

[0009] According to the present disclosure, it is possible to suppress the adhesion of ice or the like to the blade.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0011] Hereinafter, specific embodiments of the blade, the wind power generation device, and the manufacturing method of the blade according to the present disclosure will be described with reference to the drawings.

[0012] (This Embodiment) FIG. 1 is an external view of a wind power generation device according to the present embodiment.

[0013] The wind power generation device 1 includes a tower 2, a nacelle 3, a hub 4, and a plurality (for example, three) of blades 5. The tower 2 is installed on the ground and extends upward. The nacelle 3 is provided at the upper end of the tower 2 and is rotatable about a vertical axis as a rotation axis. Inside the nacelle 3, a speed increaser 6, a brake device 7, and a generator 8 are arranged. The hub 4 is provided at the front end of the nacelle 3 and is rotatable about a horizontal axis as a rotation axis. The rotation axis of the hub 4 is connected to the speed increaser 6, the brake device 7, and the generator 8 inside the nacelle 3. One end (root Q) in the longitudinal direction of the plurality of blades 5 is connected to the hub 4. The wind power generation device 1 generates electricity with the generator 8 by horizontally rotating the nacelle 3 in the direction of the wind direction and rotating the rotation axis of the hub 4 by the blades 5 receiving the force of the wind.

[0014] In cold regions, minute water droplets existing in a supercooled state in the atmosphere collide with an object and are frozen, causing icing on the wind power generation device 1. What has a great influence on the icing phenomenon on the wind power generation device 1 is the icing on the blade 5. Due to the icing on the blade 5, there may occur an "ice throw" where the ice that has adhered to the blade 5 during the operation of the wind power generation device 1 flies off, or output loss or blade breakage may occur due to fluctuations in the aerodynamic load of the blade 5. Therefore, icing on the operating blade 5 in the wind power generation device 1 installed in a cold region can be a factor in reducing the power generation efficiency or the lifespan of the wind power generation device 1. Thus, in the present embodiment, a technique for suppressing icing on the blade 5 will be described.

[0015] FIG. 2 is an external view of the pressure side (PS) of the blade 5 according to the present embodiment. FIG. 3 is an external view of the suction side (SS) of the blade 5 according to the present embodiment. FIG. 4 is a cross-sectional view of the blade 5 taken along the line A-A in FIGS. 2 and 3.

[0016] The blade 5 includes a leading edge (LE) 11 through which wind flows in during rotation, and a trailing edge (TE) 12 through which wind flows out during rotation. Note that the leading edge 11 may be read as the first edge, and the trailing edge 12 may be read as the second edge.

[0017] Further, the blade 5 includes a pressure side 13 which is the wind-receiving side surface connecting the leading edge 11 and the trailing edge 12, and a suction side 14 which is the surface on the opposite side of the pressure side 13 connecting the leading edge 11 and the trailing edge 12. Note that the pressure side 13 may be read as the first side, and the suction side 14 may be read as the second side.

[0018] The outer shell of the blade 5 is made of high-strength FRP (Fiber Reinforced Plastics) such as GFRP (Glass Fiber Reinforced Plastics) or CFRP (Carbon Fiber Reinforced Plastics).

[0019] Paint may be applied to the exterior of the surface of the blade 5. Examples of paint materials include epoxy resin or polyester resin. Further, a protector made of thermoplastic polyurethane may be added to the leading edge 11 of the blade 5 to prevent erosion.

[0020] To prevent ice accretion on the blade 5, the surface structure of a part of the leading edge 11 is different from that of other parts. For example, a part of the leading edge 11 is processed from the surface of the material of the outer shell forming the edge. For example, the surface of a part of the leading edge 11 may be processed to be smoother compared to other surfaces. Thereby, a part of the processed leading edge 11 is, for example, less likely to get dirty and suppresses the adhesion of minute water droplets existing in a supercooled state in the atmosphere, making it less likely to ice up.

[0021] Alternatively, a part of the leading edge 11 may be provided with a member different from the material of the blade 5. Hereinafter, the case where the different member is provided will be described.

[0022] The member different from the material of the blade 5 may be an anti-icing member 20 for preventing icing. The anti-icing member 20 is provided within a predetermined range from the tip P to the root Q of the blade 5 in the leading edge 11. The predetermined range (that is, the range where the anti-icing member 20 is provided) may be a range L1 from the tip P of the blade 5 to half of the length of the blade 5 in the longitudinal direction (hereinafter referred to as "within the 1 / 2 range"). Preferably, as shown in FIGS. 2 and 3, the predetermined range (that is, the range where the anti-icing member 20 is provided) may be a range L2 from the tip P of the blade 5 to one-third of the length of the blade 5 in the longitudinal direction (hereinafter referred to as "within the 1 / 3 range").

[0023] Here, the reason why the within the 1 / 3 range L2 in the leading edge 11 is preferable as the range for providing the anti-icing member 20 will be described. It has been found by the inventor's experiments that when icing occurs on the leading edge 11, the rotation of the blade 5 tends to become unstable. Also, it has been found that when icing occurs within the 1 / 3 range L1 in the leading edge 11, the rotation of the blade 5 tends to become unstable. This is presumably because when icing occurs within the 1 / 3 range L2 of the leading edge 11, large tip vortices are generated during the rotation of the blade 5. Therefore, by setting the range for providing the anti-icing member 20 to the within the 1 / 3 range L2 of the leading edge 11, it is possible to suppress the member cost and construction cost, etc., while suppressing the rotation of the blade 5 from becoming unstable due to icing.

[0024] The anti-icing member 20 may be a sheet-like member (hereinafter referred to as an anti-icing sheet). In this case, the anti-icing sheet may be attached within the above-described predetermined range (for example, within the 1 / 3 range L2) of the leading edge 11.

[0025] Further, as shown in FIGS. 2, 3, and 4, the ice adhesion prevention member 20 may be provided so as to cover the leading edge 11. In this case, the ice adhesion prevention member 20 may be provided so as to cover the leading edge 11 and a part of the pressure side 13.

[0026] Also, as shown in FIG. 4, the thickness of the portion of the ice adhesion prevention member 20 that covers the leading edge 11 may be greater than the thickness of at least a part of the portion that covers the pressure side 13. For example, the ice adhesion prevention member 20 may have the greatest thickness in the portion that covers the leading edge 11, and the thickness of the portion that covers a part of the pressure side 13 may become thinner toward the trailing edge 12. Thereby, while obtaining an ice adhesion prevention effect, the adhesion of the ice adhesion prevention member 20 (ice adhesion prevention sheet) is improved. Further, when the ice adhesion prevention member 20 has elasticity, a greater thickness of the portion that covers the leading edge 11 enhances the ice adhesion prevention effect. Also, by making the ice adhesion prevention member 20 thinner at the portion of the trailing edge 12, the self-weight is reduced, and as a result, the deflection of the ice adhesion prevention member 20 due to gravity is reduced. Thereby, the ice adhesion prevention member 20 easily adheres to a flat surface. The thin ice adhesion prevention member 20 easily maintains an even pressure distribution, and an even force acts on the entire contact surface, so the adhesion is improved.

[0027] In the cross-section of the blade 5 shown in FIG. 4, the position where the thickness L5 between the pressure side 13 and the suction side 14 is maximum is referred to as the blade thickness maximum position 31. As shown in FIG. 4, the length L4 of the portion of the ice adhesion prevention member 20 that covers a part of the pressure side 13 may be within the range from the leading edge 11 to the blade thickness maximum position 31. It has been found from the inventor's experiments that ice adhesion to the blade mainly occurs from the first edge to the portion of the maximum blade thickness. For example, the length L4 of the portion of the ice adhesion prevention member 20 that covers a part of the pressure side 13 may be one-tenth of the length L3 from the leading edge 11 to the trailing edge 12. Thereby, ice adhesion can be effectively prevented.

[0028] Further, the anti-icing member 20 may be an elastic member. Also, the surface roughness Ra of the anti-icing member 20 may be 0.2 μm or less.

[0029] The anti-icing member 20 (anti-icing sheet) may be an elastic member containing silicone. Examples of the elastic member containing silicone include silicone resin, silicone rubber, etc.

[0030] Alternatively, the anti-icing member 20 (anti-icing sheet) may be an elastic member containing fluorine. Examples of the elastic member containing fluorine include fluororesin, fluororubber, etc.

[0031] As a manufacturing method of the blade 5, an operator processes the surface structure of a part of the leading edge 11 of the blade 5 to be different from other parts. For example, the operator attaches the above-mentioned anti-icing member 20 (anti-icing sheet) within the range L2 within 1 / 3 of the leading edge 11.

[0032] FIG. 5 is a graph showing the average power output and output reduction rate of the wind power generation device 1 provided with the anti-icing member 20 on the blade 5, and the average power output and output reduction rate of the wind power generation device 1 not provided with the anti-icing member 20 on the blade 5. The graph when the anti-icing member 20 is provided on the blade 5 is the measurement result when an anti-icing sheet containing silicone is provided as the anti-icing member 20 in the range of 1 / 5 from the tip P of the blade 5 at the leading edge 11.

[0033] The graph shown in FIG. 5 was measured during a certain period in winter in a cold region. In the graph shown in FIG. 5, the horizontal axis indicates time, the left vertical axis indicates the average power output (kW) per 10 minutes, and the right vertical axis indicates the efficiency (%). The efficiency is a value indicating the ratio of the actually output average power output to the average power output that should originally be output at a predetermined wind speed. In FIG. 5, graph 50A shows the average power output per time in the wind power generation device 1 provided with the anti-icing member 20 on the blade 5, referring to the left vertical axis. Graph 50B shows the average power output per time in the wind power generation device 1 not provided with the anti-icing member 20 on the blade 5, referring to the left vertical axis. Graph 51A shows the output reduction rate per time in the wind power generation device 1 provided with the anti-icing member 20 on the blade 5, referring to the right vertical axis. Graph 51B shows the output reduction rate per time in the wind power generation device 1 not provided with the anti-icing member 20 on the blade 5, referring to the right vertical axis.

[0034] Typically, in the wind power generation device 1, as the wind speed increases, the average power output also increases up to the rated output. However, as shown in FIG. 5, in the wind power generation device 1 not provided with the anti-icing member 20 on the blade 5, after 19:30 when the wind speed was sufficiently high, as shown in graphs 50B and 51B, the average power output did not increase and the output reduction rate remained low. This is considered to be due to the change in the aerodynamic load of the blade 5 caused by icing on the blade 5, resulting in output loss.

[0035] On the other hand, in the wind power generation device 1 provided with the anti-icing member 20 on the blade 5, after 19:30 when the wind speed was sufficiently high, as shown in graphs 50A and 50B, the average power output was output up to the rated output, and the output reduction rate was also almost 0%. Thus, it can be seen that the wind power generation device 1 provided with the anti-icing member 20 on a part of the blade 5 has significantly improved power generation efficiency compared to the wind power generation device 1 not provided with the anti-icing member 20 on the blade 5. In the graph shown in FIG. 5, the output decreases in both cases where the anti-icing member 20 is provided on the blade 5 and where it is not provided immediately before 21:00, but this is because the wind power generation device 1 was stopped.

[0036] That is, by providing the anti-icing member 20 within the range L2 (for example, the above-mentioned 1 / 5 range) within the 1 / 3 range at the leading edge 11, it is possible to suppress the rotation of the blade 5 from becoming unstable and improve the power generation efficiency in the wind power generation device 1 installed in a cold region.

[0037] (Summary of this embodiment) From the description of the above embodiment, the following technologies are disclosed. <Technology 1> The blade 5, one end (root Q) of which is connected to the rotating shaft and used, includes a first edge (for example, the leading edge 11) on the side where the wind flows in during rotation, a second edge (for example, the trailing edge 12) on the side where the wind flows out during rotation, a first side (for example, the pressure side 13) which is the surface connecting the first edge and the second edge, and a second side (for example, the suction side 14) which is the surface opposite to the first side and connecting the first edge and the second edge, and is characterized in that the surface structure of a part of the first edge is different from that of the other part of the first edge.

[0038] <Technology 2> In the blade (5) described in Technology 1, a member different from the material of the blade (5) is provided on a part of the first edge.

[0039] <Technology 3> In the blade (5) described in Technology 1 or 2, the member different from the material of the blade (5) is an anti-icing member (20) for preventing icing.

[0040] <Technology 4> In the blade (5) described in Technology 3, the anti-icing member (20) is provided within a predetermined range from the other end (tip P), which is opposite to one end (root Q) of the blade (5), toward one end at the first edge.

[0041] <Technology 5> In the blade (5) described in Technology 4, the predetermined range is a range (L1) from the other end (root Q) of the blade (5) to half of the length of the blade 5 in the longitudinal direction.

[0042] <Technology 6> In the blade (5) described in Technology 4 or 5, the predetermined range is a range (L2) from the other end (tip P) of the blade (5) to one-third of the length of the blade (5) in the longitudinal direction.

[0043] <Technology 7> In the blade (5) described in any one of Technologies 3 to 6, the anti-icing member (20) is provided so as to cover the first edge.

[0044] <Technology 8> In the blade (5) described in Technology 7, the anti-icing member (20) is provided so as to cover the first edge and a part of the first side.

[0045] <Technology 9> In the blade (5) described in any one of Technologies 3 to 8, the anti-icing member (20) has elasticity, the thickness of the part covering the first edge is the largest, and the thickness of the part covering a part of the first side becomes thinner toward the second edge.

[0046] <Technology 10> In the blade (5) according to Technique 8 or 9, the portion covering a part of the first side of the ice adhesion prevention member (20) is within the range from the first edge to the position (31) of the maximum thickness between the first side and the second side.

[0047] <Technique 11> In the blade (5) according to any one of Techniques 3 to 10, the ice adhesion prevention member (20) is a sheet-like member.

[0048] <Technique 12> In the blade (5) according to any one of Techniques 3 to 11, the ice adhesion prevention member (20) is a member containing silicone.

[0049] <Technique 13> In the blade (5) according to any one of Techniques 3 to 11, the ice adhesion prevention member (20) is a member containing fluorine.

[0050] <Technique 14> In the blade (5) according to Technique 1, a part of the first edge is obtained by processing the surface of the material constituting the edge.

[0051] <Technique 15> A wind power generation device (1) including the blade (5) according to any one of the above Techniques 1 to 14.

[0052] <Technique 16> In a method for manufacturing a blade (5) having one end (root Q) connected to a rotating shaft and used, the blade (5) includes a first edge (for example, leading edge 11) on the side where wind flows in during rotation, a second edge (for example, trailing edge 12) on the side where wind flows out during rotation, a first side (for example, pressure side 13) which is a surface connecting the first edge and the second edge, and a second side (for example, suction side 14) which is a surface opposite to the first side and connecting the first edge and the second edge, and the surface structure of a part of the first edge is processed to be different from other parts.

[0053] Note that the present disclosure is not limited to the above-described embodiments, and can be appropriately modified, improved, etc. In addition, the material, shape, dimensions, numerical values, form, number, arrangement location, etc. of each component in the above-described embodiments are arbitrary as long as the present invention can be achieved, and are not limited.

Industrial Applicability

[0054] The technology of the present disclosure is useful for a blade that rotates by receiving the force of wind and a wind power generation device including the blade.

Explanation of Reference Numerals

[0055] 1 Wind power generation device 2 Tower 3 Nacelle 4 Hub 5 Blade 6 Speed increaser 7 Brake device 8 Generator 11 Leading edge 12 Trailing edge 13 Pressure side 14 Suction side 20 Ice prevention member 31 Maximum blade thickness position

Claims

1. A blade having one end connected to a rotating shaft and used, comprising: a first edge on the side where wind flows in during rotation; a second edge on the side where wind flows out during rotation; a first side which is a plane connecting the first edge and the second edge; a second side which is a plane opposite to the first side and connecting the first edge and the second edge, wherein a surface structure of a part of the first edge is different from that of other parts of the first edge. Blade.

2. A part of the first edge is provided with a member different from the material of the blade. The blade according to Claim 1.

3. The member different from the material of the blade is an anti-icing member for preventing icing. The blade according to Claim 2.

4. The anti-icing member is provided within a predetermined range from the other end of the blade, which is opposite to the one end of the blade, towards the one end on the first edge. The blade according to Claim 3.

5. The predetermined range is a range from the other end of the blade to half of the length of the blade in the longitudinal direction. The blade according to Claim 4.

6. The predetermined range is a range from the other end of the blade to one-third of the length of the blade in the longitudinal direction. The blade according to Claim 5.

7. The anti-icing member is provided so as to cover the first edge. The blade according to Claim 4.

8. The anti-icing member is provided so as to cover the first edge and a part of the first side. The blade according to Claim 7.

9. The anti-icing member has elasticity, and the thickness of the part covering the first edge is thicker than at least a part of the thickness of the part covering the first side. The blade according to Claim 8.

10. The part of the anti-icing member covering a part of the first side is within a range from the first edge to the position of the maximum thickness between the first side and the second side. The blade according to Claim 8.

11. The anti-icing member is a sheet-like member. The blade according to any one of Claims 3 to 10.

12. The anti-icing member is a member containing silicone. The blade according to Claim 11.

13. The anti-icing member is a member containing fluorine. The blade according to Claim 11.

14. A part of the first edge is obtained by processing the surface of the material constituting the edge. The blade according to claim 1.

15. Comprising the blade according to claim 1, Wind power generation device.

16. A method for manufacturing a blade used with one end connected to a rotating shaft, The blade is A first edge on the side where wind flows in during rotation, A second edge on the side where wind flows out during rotation, A first side that is a plane connecting the first edge and the second edge, A second side that is a plane on the opposite side of the first side and connecting the first edge and the second edge, and is provided with, Processing is performed so that the surface structure of a part of the first edge is different from other parts of the first edge. Method for manufacturing a blade.

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