Power increasing blade structure suitable for low-wind-speed fan

Abstract

The invention provides a power-increasing blade structure suitable for a low-wind-speed fan, which comprises a hub, three fan blades and an annular power-increasing structure, and the three fan blades are circumferentially and uniformly distributed by taking the hub as a center; the annular power increasing structure comprises three arc-shaped wing-shaped pieces, one wing-shaped piece is arranged between every two adjacent fan blades, and the two ends of each wing-shaped piece are connected with the two corresponding fan blades respectively, so that an annular structure is defined by the three wing-shaped pieces. According to the power increasing blade structure suitable for the low-wind-speed draught fan, the low-wind-speed performance of the draught fan can be improved, and meanwhile wake flow turbulence and wind speed and wind energy losses behind the draught fan are reduced.

Description

Technical Field

[0001] The invention relates to the technical field of wind power generation, and in particular to a power-enhancing blade structure suitable for a wind turbine with small wake and low wind speed. Background Art

[0002] At present, in the field of wind power generation, the development of small tail wind turbines with low wind speed has far-reaching and significant significance. Small tail wind turbines with low wind speed have greatly expanded the geographical scope of wind energy development. In the past, wind energy development was often limited to specific areas with high wind speeds. The emergence of small tail wind turbines with low wind speeds has enabled those areas with relatively low wind speeds but large areas to effectively utilize wind energy, thereby greatly increasing the total amount of exploitable wind energy resources.

[0003] The existing wind turbine generator set usually adopts a three-blade structure. In order to improve the utilization rate of wind energy resources, the blade size of the wind turbine generator set can reach hundreds of meters. This type of wind turbine generator set is difficult to be effectively used in low wind speed areas. Therefore, how to improve the structure of the existing three-blade wind turbine to improve the low wind speed power generation performance is a technical problem that technicians in this field need to solve. Summary of the invention

[0004] The object of the present invention is to provide a power-enhancing blade structure suitable for a low-wind-speed wind turbine, which can improve the low-wind-speed performance of the wind turbine and reduce the wake turbulence and wind speed wind energy loss behind the wind turbine.

[0005] The present invention provides a power-enhancing blade structure suitable for a low-wind-speed wind turbine, comprising a hub, three fan blades and an annular power-enhancing structure, wherein the three fan blades are evenly distributed on a circumference with the hub as the center; the annular power-enhancing structure comprises three arc-shaped airfoil pieces, one of which is provided between each two adjacent fan blades, and the two ends of each airfoil piece are respectively connected to the corresponding two fan blades, so that the three airfoil pieces are enclosed to form a circular ring structure.

[0006] According to a power-enhancing blade structure suitable for a low wind speed wind turbine provided by the present invention, a rolling bearing is respectively installed on each of the wind turbine blades, the inner ring of the rolling bearing is connected and fixed to the wind turbine blade, and the outer ring of the rolling bearing is connected and fixed to two adjacent airfoil sheets.

[0007] According to a power-enhancing blade structure suitable for a low-wind-speed wind turbine provided by the present invention, the inner ring of the rolling bearing is sleeved on the outside of the wind turbine blade, and the inner ring of the rolling bearing is connected and fixed to the outer surface of the wind turbine blade.

[0008] According to a power-enhancing blade structure suitable for a low wind speed wind turbine provided in the present invention, a mounting groove is opened on one side of the wind turbine blade, a part of the rolling bearing is arranged in the mounting groove, and the rest of the rolling bearing is arranged outside the wind turbine blade, and one side of the inner ring of the rolling bearing is connected and fixed to the inner wall of the mounting groove, and the other side of the inner ring of the rolling bearing is connected and fixed to the outer surface of the wind turbine blade.

[0009] According to a power-enhancing blade structure suitable for a low-wind-speed wind turbine provided by the present invention, two adjacent airfoil pieces are respectively connected and fixed to opposite sides of the outer ring of the rolling bearing.

[0010] According to a power-enhancing blade structure suitable for a low-wind-speed wind turbine provided by the present invention, the length between the installation position of the airfoil on the wind turbine blade and the root of the wind turbine blade is 1 / 3 of the overall length of the wind turbine blade.

[0011] According to a power-enhancing blade structure suitable for a low wind speed wind turbine provided by the present invention, the cross-section of the airfoil is an airfoil structure, the chord length direction of the airfoil forms an angle of 10 to 15 degrees with the horizontal plane, and the leading edge of the airfoil is arranged toward the windward side.

[0012] According to a power-enhancing blade structure suitable for a low wind speed wind turbine provided in the present invention, the airfoil comprises an airfoil shell and a reinforced frame arranged in the airfoil shell, the airfoil shell is made of carbon fiber material, and the reinforced frame is a PET sandwich structure frame.

[0013] According to a power-enhancing blade structure suitable for a low wind speed wind turbine provided by the present invention, a plurality of reinforced frames are provided, and the plurality of reinforced frames are arranged in sequence and at intervals along the length extension direction of the airfoil shell; each of the reinforced frames includes a front support rod, an upper connecting rod, a rear support rod and a lower connecting rod, the length of the front support rod is greater than that of the rear support rod, and the front support rod, the upper connecting rod, the rear support rod and the lower connecting rod are connected end to end to form a quadrilateral frame body, and the two diagonals of the quadrilateral frame body are connected by a reinforcing rod.

[0014] According to a power-enhancing blade structure suitable for a low-wind-speed wind turbine provided by the present invention, the diameter of the circular ring formed by the three airfoils is 60 to 65 meters, the width of each airfoil is 5 meters, and the maximum thickness of each airfoil is 1 meter.

[0015] The power-enhancing blade structure suitable for a low-wind-speed fan provided by the present invention is achieved by installing an annular power-enhancing structure on three fan blades, the annular power-enhancing structure comprising three arc-shaped airfoils, and by arranging an airfoil between each two adjacent fan blades, the two ends of each airfoil are respectively connected to the corresponding two fan blades, so that the three airfoils are enclosed to form a circular ring structure; by installing the annular power-enhancing structure on the fan blades, the Bernoulli principle can be used to increase the air flow in the ring, thereby improving the low-wind-speed performance of the fan, while reducing the wake turbulence and wind speed and wind energy loss behind the fan, and by installing the annular power-enhancing structure on the fan blades, the overall structural stability of the fan can be increased, the blade vibration can be suppressed to a certain extent, and the reliability of the fan operation can be improved.

[0016] The power-enhancing blade structure suitable for low wind speed wind turbines provided by the present invention adds an annular power-enhancing structure on the wind turbine blades, so that the wind turbine has higher low wind speed power generation performance than traditional wind turbines, and its wind speed and wake stability are also better than traditional wind turbines of the same size, which reduces the mutual spacing between wind turbines in the wind farm when they are arranged, and improves land utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a schematic diagram of a power-increasing blade structure applicable to a low-wind-speed wind turbine according to the present invention;

[0019] Figure 2 It is a schematic diagram of a structure in which a fan blade is connected to an airfoil through a rolling bearing in a power-enhancing blade structure applicable to a low-wind-speed fan of the present invention;

[0020] Figure 3 It is another structural schematic diagram of a power-enhancing blade structure applicable to a low-wind-speed fan of the present invention, in which a fan blade is connected to an airfoil through a rolling bearing;

[0021] Figure 4 It is a schematic diagram of the arrangement of the cross section of the airfoil relative to the horizontal plane in the power-enhancing blade structure applicable to a low-wind-speed wind turbine of the present invention;

[0022] Figure 5 The figure is a schematic diagram of the internal structure of the airfoil in the power-enhancing blade structure suitable for low-wind-speed wind turbines according to the present invention.

[0023] Description of reference numerals:

[0024] 100, wheel hub; 200, fan blade; 300, annular power amplification structure;

[0025] 1. Airfoil; 101. Airfoil shell; 102. Reinforced frame; 102A. Front support rod; 102B. Upper connecting rod; 102C. Rear support rod; 102D. Lower connecting rod; 102E. Reinforcement rod;

[0026] 2. Rolling bearings. DETAILED DESCRIPTION

[0027] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0029] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined. In addition, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] like Figures 1 to 5As shown, the power-enhancing blade structure for a low-speed wind turbine according to an embodiment of the present invention comprises a hub 100, three wind turbine blades 200 and an annular power-enhancing structure 300, wherein the three wind turbine blades 200 are evenly distributed around the hub 100. The annular power-enhancing structure 300 comprises three arc-shaped airfoil pieces 1, one airfoil piece 1 is respectively arranged between each two adjacent wind turbine blades 200, and the two ends of each airfoil piece 1 are respectively connected to the corresponding two wind turbine blades 200, so that the three airfoil pieces 1 are enclosed to form an annular structure.

[0031] The power-enhancing blade structure suitable for a low wind speed wind turbine of the embodiment of the present invention can utilize the Bernoulli principle to increase the air flow in the ring by installing an annular power-enhancing structure 300 on the wind turbine blade 200, thereby improving the low wind speed performance of the wind turbine, while reducing the wake turbulence and wind speed and wind energy loss behind the wind turbine. Furthermore, by installing the annular power-enhancing structure 300 on the wind turbine blade 200, the overall structural stability of the wind turbine can be increased, the vibration of the wind turbine blade can be suppressed to a certain extent, and the reliability of the fan operation can be improved.

[0032] The power-enhancing blade structure suitable for low wind speed wind turbines in the embodiment of the present invention adds an annular power-enhancing structure 300 to the wind turbine blade 200, so that the wind turbine has higher low wind speed power generation performance than traditional wind turbines, and the wind speed and wake stability are better than traditional wind turbines of the same size, which reduces the mutual spacing between wind turbines in the wind farm layout and improves land utilization.

[0033] Specifically, the length between the installation position of the airfoil 1 on the fan blade 200 and the root of the fan blade 200 is 1 / 3 of the overall length of the fan blade 200. That is, the airfoil 1 is installed at a position of 1 / 3 of the length of the fan blade 200. The cross section of the airfoil 1 is an airfoil structure, the chord length direction of the airfoil 1 forms an angle of 10 to 15 degrees with the horizontal plane, and the leading edge of the airfoil 1 is arranged toward the windward surface. When the fan is running, each airfoil 1 can rotate with each fan blade 200. When the airflow passes through the annular power-enhancing structure 300 formed by the three airfoils 1, the flow velocity in the annular power-enhancing structure 300 increases and the air pressure decreases due to the Bernoulli principle, thereby increasing the wind energy flowing through the swept area of ​​the fan blade and increasing the wind speed behind the fan blade. Therefore, the power-enhancing blade structure suitable for low wind speed wind turbines in the embodiment of the present invention can effectively solve the problems of poor low wind speed performance and high wake of 100-meter-class blade wind turbines, especially for some areas with low wind speed and small space, and can greatly improve the installed capacity and power generation performance.

[0034] Specifically, the airfoil 1 includes an airfoil shell 101 and a reinforced frame 102 arranged in the airfoil shell 101, wherein the airfoil shell 101 is made of carbon fiber material, and the reinforced frame 102 adopts a PET sandwich structure frame, so as to ensure that the annular power amplification structure 300 has high stability while also helping to improve the stability of the 100-meter-class wind turbine blades.

[0035] Among them, a plurality of reinforced frames 102 are arranged in each airfoil shell 101, and the plurality of reinforced frames 102 are arranged in sequence and spaced along the length extension direction of the airfoil shell 101. Each reinforced frame 102 includes a front support rod 102A, an upper connecting rod 102B, a rear support rod 102C and a lower connecting rod 102D, the front support rod 102A is arranged close to the leading edge of the airfoil shell 101, and the rear support rod 102C is arranged close to the trailing edge of the airfoil shell 101, so the length of the front support rod 102A is greater than the length of the rear support rod 102C, and the front support rod 102A, the upper connecting rod 102B, the rear support rod 102C and the lower connecting rod 102D are connected end to end to form a quadrilateral frame, and are connected at two diagonals of the quadrilateral frame by reinforcing rods 102E, respectively, to ensure that the reinforced frame 102 has high structural strength and stability.

[0036] Specifically, for a 100-meter-class wind turbine blade, the diameter of the annular power-increasing structure 300 formed by the three airfoil sheets 1 can be set to 60-65 meters, the width of each airfoil sheet 1 can be set to 5 meters, and the maximum thickness of each airfoil sheet 1 can be set to 1 meter. Thus, the three airfoil sheets 1 form an integral annular power-increasing structure 300, which can effectively reduce the vibration of the 100-meter-class ultra-long wind turbine blades during operation and reduce the risk of tower sweeping. Moreover, the power-increasing blade structure applicable to low-wind-speed wind turbines of the embodiment of the present invention can also be used to modify wind turbines in existing wind farms to improve power generation performance.

[0037] In some embodiments of the present invention, a rolling bearing 2 is respectively installed on each wind blade 200, the inner ring of the rolling bearing 2 is connected and fixed to the wind blade 200, and the outer ring of the rolling bearing 2 is connected and fixed to two adjacent airfoil pieces 1, thereby achieving reliable installation of the three airfoil pieces 1 on the three wind blades 200. Moreover, since the airfoil pieces 1 and the wind blades 200 are connected by the rolling bearings 2, the pitch control of the wind blades 200 will not be affected.

[0038] In a specific embodiment, the inner ring of the rolling bearing 2 can be mounted on the outside of the fan blade 200, and the inner ring of the rolling bearing 2 is connected and fixed to the outer surface of the fan blade 200, while the two adjacent airfoil pieces 1 are respectively connected and fixed to the opposite sides of the outer ring of the rolling bearing 2, thereby achieving reliable installation between the airfoil piece 1 and the fan blade 200, and the airfoil piece 1 will not affect the pitch change of the fan blade 200 after installation.

[0039] In another specific embodiment, a mounting groove may be opened on one side of the fan blade 200, and a portion of the rolling bearing 2 is arranged in the mounting groove, and the remaining portion of the rolling bearing 2 is arranged outside the fan blade 200, and one side of the inner ring of the rolling bearing 2 is connected and fixed to the inner wall of the mounting groove, and the other side of the inner ring of the rolling bearing 2 is connected and fixed to the outer surface of the fan blade 200, and two adjacent airfoil pieces 1 are respectively connected and fixed to the opposite sides of the outer ring of the rolling bearing 2, thereby achieving reliable installation between the airfoil piece 1 and the fan blade 200, and the airfoil piece 1 will not affect the pitch change of the fan blade 200 after installation.

[0040] In order to facilitate the transformation of wind turbines in existing wind farms, when an annular power-increasing structure 300 is added to the wind turbine blade 200, the inner ring of the rolling bearing 2 and the wind turbine blade 200 can be connected and installed by connecting plates, thereby facilitating construction and installation.

[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A power-enhancing blade structure suitable for a low-speed wind turbine, characterized in that: It includes a hub, three fan blades and an annular power amplification structure, wherein the three fan blades are evenly distributed on a circle with the hub as the center; the annular power amplification structure includes three arc-shaped airfoil pieces, one airfoil piece is respectively arranged between each two adjacent fan blades, and the two ends of each airfoil piece are respectively connected to the corresponding two fan blades, so that the three airfoil pieces are enclosed to form a circular ring structure.

2. The power-enhancing blade structure suitable for a low-speed wind turbine according to claim 1, characterized in that: A rolling bearing is respectively installed on each of the fan blades, the inner ring of the rolling bearing is connected and fixed to the fan blade, and the outer ring of the rolling bearing is connected and fixed to two adjacent airfoil sheets.

3. The power-enhancing blade structure suitable for a low-speed wind turbine according to claim 2, characterized in that: The inner ring of the rolling bearing is sleeved on the outside of the fan blade, and the inner ring of the rolling bearing is connected and fixed to the outer surface of the fan blade.

4. The power-enhancing blade structure suitable for a low-speed wind turbine according to claim 2, characterized in that: A mounting groove is provided on one side of the fan blade, a portion of the rolling bearing is arranged in the mounting groove, and the remaining portion of the rolling bearing is arranged outside the fan blade, and one side of the inner ring of the rolling bearing is connected and fixed to the inner wall of the mounting groove, and the other side of the inner ring of the rolling bearing is connected and fixed to the outer surface of the fan blade.

5. The power-enhancing blade structure suitable for a low-speed wind turbine according to claim 2, characterized in that: Two adjacent airfoil sheets are respectively connected and fixed to opposite sides of the outer ring of the rolling bearing.

6. The power-enhancing blade structure suitable for a low-speed wind turbine according to claim 1, characterized in that: The length between the installation position of the airfoil on the fan blade and the root of the fan blade is 1 / 3 of the overall length of the fan blade.

7. The power-enhancing blade structure for a low-speed wind turbine according to claim 1, characterized in that: The cross section of the airfoil is an airfoil structure, the chord length direction of the airfoil forms an angle of 10 to 15 degrees with the horizontal plane, and the leading edge of the airfoil is arranged toward the windward surface.

8. The power-enhancing blade structure for a low-speed wind turbine according to claim 1, characterized in that: The airfoil sheet comprises an airfoil shell and a reinforced frame arranged in the airfoil shell. The airfoil shell is made of carbon fiber material, and the reinforced frame is a PET sandwich structure frame.

9. The power-enhancing blade structure suitable for a low-speed wind turbine according to claim 8, characterized in that: There are multiple reinforced frames, and the multiple reinforced frames are arranged in sequence along the length extension direction of the wing-shaped shell; each of the reinforced frames includes a front support rod, an upper connecting rod, a rear support rod and a lower connecting rod, the length of the front support rod is greater than the length of the rear support rod, and the front support rod, the upper connecting rod, the rear support rod and the lower connecting rod are connected end to end to form a quadrilateral frame, and the two diagonals of the quadrilateral frame are connected by a reinforcing rod.

10. The power-enhancing blade structure suitable for a low-speed wind turbine according to claim 1, characterized in that: The diameter of the circular ring formed by the three airfoil pieces is 60-65m, the width of each airfoil piece is 5m, and the maximum thickness of each airfoil piece is 1m.

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