Fan blade, fan and fan blade anti-sweeping method

Abstract

The invention discloses a fan blade, a fan and a fan blade anti-sweeping method, a main blade and a tail blade of the fan blade are detachably connected through a connecting assembly, the fan blade further comprises a position detection device, and the position detection device is used for detecting the distance between the fan blade and a fan tower drum. And the connecting assembly can release the connection between the main blade and the tail blade when the minimum distance is smaller than a threshold value. In the operation process of the fan, the distance between the fan blade and the fan tower drum is actively detected by using the position detection device, and when the risk that the fan blade sweeps the fan tower drum occurs, the connection assembly can timely release the connection between the main blade and the tail blade, so that the tail blade is separated from the main blade, the fan blade is prevented from sweeping the fan tower drum, and the service life of the fan is prolonged. The damage degree and the economic loss of the fan are reduced, and the difficulty of subsequent repair work of the fan is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of wind turbine power generation, and in particular to a wind turbine blade, a wind turbine and a wind turbine blade anti-sweep method. Background Art

[0002] As a new type of energy, wind power generation is being used more and more widely. In recent years, with the development of wind power technology, the power of the unit has become larger and larger, the corresponding blades have become longer and longer, the required tower height has become higher and higher, and the tower diameter has become larger and larger. Due to the imperfection of the wind turbine control system, when the blades are deformed by the wind, there is a delay in the response to the blade control, an overreaction, etc., and the blade sweeps the tower often. As a thin-walled structure, the steel tower is generally 4m to 5m in diameter and the wall thickness is 15mm to 40mm. When sweeping the tower, it is very easy to cause a tower collapse accident. Even if the blade rotates at a low speed and does not collapse during the tower sweep, the blade will be broken and the blade needs to be replaced as a whole. When the blade needs to be replaced later, in addition to the cost of the blade itself, a 1000t-level main crane is required to enter the site, which is extremely expensive, so the loss caused is very large. Summary of the invention

[0003] The technical problem to be solved by the present invention is to overcome the defects in the prior art that the fan blades sweep the tower causing blade damage and tower collapse, and to provide a fan blade, a fan and a fan blade anti-sweep method.

[0004] The present invention solves the above technical problems through the following technical solutions:

[0005] A fan blade, comprising a main blade close to a fan main unit, a tail blade far from the fan main unit, and a connecting assembly, wherein the main blade and the tail blade are detachably connected via the connecting assembly;

[0006] The fan blade further comprises a position detection device, wherein the position detection device is used to detect the distance between the fan blade and the fan tower;

[0007] The connection assembly is capable of releasing the connection between the main blade and the tail blade when the distance is less than a threshold value.

[0008] In the present technical solution, the fan blade is divided into two parts, a main blade and a tail blade, which are connected by a connecting assembly. At the same time, a position detection device is provided to detect the distance between the fan blade and the tower during the operation of the fan blade, and control the limit device according to the distance. The connecting assembly can maintain or release the connection between the main blade and the tail blade according to the feedback of the position detection device. When the distance between the fan blade and the fan tower is not less than a threshold value, the main blade and the tail blade are kept connected; when the distance between the fan blade and the fan tower is less than a threshold value, the connection between the main blade and the tail blade is released, so that the tail blade can be separated from the main blade under the action of centrifugal force, thereby preventing the fan blade from sweeping the fan tower, and realizing active anti-sweeping of the fan blade.

[0009] Preferably, the connection assembly comprises:

[0010] A first connecting member and a second connecting member, wherein the first connecting member and the second connecting member are respectively arranged on the main blade and the tail blade, the second connecting member is arranged and sleeved on the outer side of the first connecting member, the inner side surface of the second connecting member and the outer side surface of the first connecting member abut against each other, the first connecting member has a first limiting hole, the second connecting member has a second limiting hole, and the first limiting hole and the second limiting hole are arranged correspondingly;

[0011] A fixing member, wherein two ends of the fixing member are respectively inserted into the first limiting hole and the second limiting hole which are correspondingly arranged, and the structure of the second limiting hole is arranged to limit the freedom of the fixing member to move in a direction away from the first limiting hole;

[0012] an elastic member, the elastic member being used to exert a force on the fixing member to move toward the first limiting hole and away from the second limiting hole;

[0013] A limiting device is used to limit the fixing member from being separated from the second limiting hole, and can release the limitation on the fixing member when the distance is less than a threshold value.

[0014] In the present technical solution, the connection assembly is specifically achieved by inserting the fixing member into the first limiting hole and the second limiting hole of the main blade and the tail blade at the same time, so as to connect the main blade and the tail blade. Among them, the fixing member can be disengaged from the second limiting hole by setting an elastic member. Specifically, when the distance between the wind turbine blade and the wind turbine tower is not less than a threshold value, the fixing member is limited to the first limiting hole and the second limiting hole by a limiting device, so that the main blade and the tail blade remain in a connected state. When the distance between the wind turbine blade and the wind turbine tower is less than a threshold value, the limiting device releases the restriction on the fixing member, so that the fixing member is disengaged from the second limiting hole under the action of the elastic member, and the main blade and the tail blade cannot maintain a connected state.

[0015] Preferably, the limiting device comprises:

[0016] an airbag, the airbag abutting against an end of the fixing member relatively close to the first limiting hole, so as to limit the fixing member from being separated from the second limiting hole;

[0017] An explosive device, the explosive device is used to detonate the airbag;

[0018] A controller is connected to the blasting device and the position detection device respectively, and is used to obtain the minimum distance detected by the position detection device and control the blasting device to start when the minimum distance is less than a threshold value.

[0019] In this technical solution, an airbag is used to limit the latch, and a controller and an explosion device are used to control whether the airbag explodes. The airbag has a light structure, imposes a light burden on the fan blades, and the overall structure is simple and reliable.

[0020] Preferably, the first limiting hole and the second limiting hole extend along the normal direction of the outer surface of the first connecting member, and the airbag is arranged inside the inner surface of the first connecting member.

[0021] Preferably, the first connecting member is arranged on the main blade and is formed integrally with the main blade; the second connecting member is arranged on the tail blade and is formed integrally with the tail blade.

[0022] In the present technical solution, by integrally forming the first connecting member with the main blade and the second connecting member with the tail blade, on the one hand, the connection between the first connecting member and the main blade, and the connection between the second connecting member and the tail blade can be made more reliable; on the other hand, there is no need to drill holes on the main blade and the tail blade, and the main blade and the tail blade can be detachably connected without affecting the structural strength of the main blade and the tail blade.

[0023] Preferably, the elastic member is compressed in the second limiting hole, and along the expansion and contraction direction of the elastic member, two ends of the elastic member abut against the bottom wall of the second limiting hole and the fixing member respectively.

[0024] Preferably, the number of the second limiting holes and the number of the first limiting holes are both plural, the second limiting holes and the first limiting holes are arranged in one-to-one correspondence, and the fixing piece is inserted into at least one of the correspondingly arranged second limiting holes and the first limiting holes.

[0025] First limiting hole Second limiting hole Preferably, the first connecting member is a first connecting ring, the second connecting member is a second connecting ring, and the inner peripheral side surface of the second connecting ring abuts against the outer peripheral side surface of the first connecting ring.

[0026] Preferably, it is characterized in that the fixing member comprises a rectangular latch.

[0027] Preferably, the length of the fan blade is L, the length of the tail blade is a, and 0.05L≤a≤0.15L.

[0028] A wind turbine comprises a wind turbine tower and the wind turbine blades as described above.

[0029] Preferably, the wind turbine further comprises a nacelle, and the position detection device is arranged at the bottom of the nacelle.

[0030] A fan blade anti-sweep method comprises the following steps:

[0031] The fan blades are divided into main blades close to the fan main unit and tail blades far away from the fan main unit along the blade axis, and the main blades and the tail blades are connected by a connecting component;

[0032] The distance from the wind turbine blade to the wind turbine tower is detected. If the distance is less than a threshold value corresponding to the detected point, a control signal is sent to the connection component, and the connection component controls the tail blade to separate from the main blade.

[0033] In the present technical solution, the wind turbine blades are divided into two parts, a main blade and a tail blade, which are connected by a connecting component. During the operation of the wind turbine blades, the distance from the wind turbine blades to the wind turbine tower is detected. If the detected distance is less than the threshold corresponding to the detected point, it indicates that the wind turbine blades are at risk of sweeping the wind turbine tower. At this time, a control signal is sent by the connecting component to control the tail blades to separate from the main blades, thereby preventing the wind turbine blades from sweeping the wind turbine tower, reducing the degree of damage to the wind turbine and the economic losses, while reducing the difficulty of subsequent repair work.

[0034] Preferably, the distance is the minimum value of the horizontal distance from the wind turbine blades to the wind turbine tower.

[0035] The positive progressive effect of the present invention is that the fan blades, fan and fan blade anti-sweep method of the present invention can actively detect the distance between the fan blades and the fan tower during the operation of the fan, and can promptly separate the tail blades from the main blades when there is a risk that the fan blades will sweep the fan tower, thereby preventing the fan blades from sweeping the fan tower, reducing the degree of damage to the fan and economic losses, and reducing the difficulty of subsequent repair work on the fan. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a schematic diagram of the structure of the fan blade according to Example 1 of the present invention.

[0037] Figure 2 This is a schematic structural diagram of the main blade and the first connecting ring of Example 1 of the present invention.

[0038] Figure 3 It is a schematic structural diagram of the tail blade and the second connecting ring of Example 1 of the present invention.

[0039] Figure 4 This is a schematic diagram of the structure of the first connecting ring and the second connecting ring in Example 1 of the present invention.

[0040] Figure 5 It is a schematic diagram of the partial cross-sectional structure of the connection component of Example 1 of the present invention.

[0041] Figure 6 for Figure 5 Enlarged schematic diagram of part A.

[0042] Description of reference numerals:

[0043] Fan blade 1

[0044] Main blade 11

[0045] Tail blade 12

[0046] The first connecting member 131

[0047] The second connecting member 132

[0048] Fixing 133

[0049] Elastic member 134

[0050] Airbag 135

[0051] Signal line 14 DETAILED DESCRIPTION

[0052] The present invention is further described below by way of examples, but the present invention is not limited to the scope of the examples.

[0053] Example 1

[0054] like Figure 1-Figure 6 As shown, this embodiment provides a wind turbine, which includes a wind turbine blade 1 and a wind turbine tower (not shown in the figure).

[0055] Specific as Figure 1As shown, the length L of the fan blade 1 is 90m. The fan blade 1 includes a main blade 11 close to the fan main unit, a tail blade 12 far away from the fan main unit, and a connecting assembly. The separation point between the main blade 11 and the tail blade 12 is 5m from the blade tip a, and the main blade 11 and the tail blade 12 are detachably connected through the connecting assembly. The fan blade 1 also includes a position detection device (not shown in the figure), which is used to detect the distance between the fan blade and the fan tower; at the same time, the connecting assembly can release the connection between the main blade 11 and the tail blade 12 when the distance is less than a threshold. By dividing the fan blade 1 into two parts, the main blade 11 and the tail blade 12 are connected through the connecting assembly, and a position detection device is set to detect the distance between the fan blade 1 and the fan tower during the operation of the fan blade 1, and control the limit device according to the distance. The connecting assembly can maintain or release the connection between the main blade 11 and the tail blade 12 according to the feedback of the position detection device. When the distance between the fan blade 1 and the wind tower is not less than a threshold value, the main blade 11 and the tail blade 12 remain connected; when the distance between the fan blade 1 and the wind tower is less than a threshold value, the connection between the main blade 11 and the tail blade 12 is released, so that the tail blade 12 can be separated from the main blade 11 under the action of centrifugal force, thereby preventing the fan blade 1 from sweeping the wind tower, thereby realizing active anti-sweeping of the fan blade 1.

[0056] Generally speaking, the boundary position between the main blade 11 and the tail blade 12 is generally located 3m to 10m near the blade tip.

[0057] Specifically, if Figure 2-Figure 6 As shown, the connection assembly includes a first connection member 131, a second connection member 132, a fixing member 133, an elastic member 134 and a limiting device. Among them, the first connection member 131 is arranged on the main blade 11, the second connection member 132 is arranged on the tail blade 12, the second connection member 132 is arranged to be sleeved on the outside of the first connection member 131, the inner surface of the second connection member 132 and the outer surface of the first connection member 131 are mutually abutted, the first connection member 131 has a plurality of first limiting holes for the fixing member 133 to be inserted, and the second connection member 132 also has a plurality of second limiting holes for the fixing member 133 to be inserted, these first limiting holes and second limiting holes are arranged correspondingly, so that the two ends of each fixing member 133 can be inserted into any group of correspondingly arranged first limiting holes and second limiting holes, so that the main blade 11 and the tail blade 12 remain connected. Specifically in this embodiment, fixing members 133 are inserted in all the first limiting holes and second limiting holes to disperse stress.

[0058] At the same time, the elastic member 134 is arranged between the fixing member 133 and the second limiting hole, and has a force on the fixing member 133 to break away from the second limiting hole. The limiting device is arranged at the other end of the fixing member 133, and is used to limit the fixing member 133 from breaking away from the second limiting hole. The limiting device can release the restriction on the fixing member 133 when the minimum distance is less than the threshold. Specifically in this embodiment, the first limiting hole is a through hole, which provides a space for the elastic member 134 to break away from the second limiting hole; the second limiting hole is a blind hole, so as to achieve the purpose of limiting the freedom of the fixing member to move in the direction away from the first limiting hole. At the same time, the second limiting hole also facilitates the elastic member to be compressed in the second limiting hole by abutting the bottom wall of the blind hole and the fixing member 133 at both ends, so as to provide a force for the fixing member 133 to break away from the second limiting hole. Among them, the setting of the threshold value is related to the detection point of the position detection device, and different detection points have different threshold values. The threshold value is the prior art, that is, the threshold value of different detection points can be determined according to the statistical data or calculation method in the prior art, which will not be repeated here.

[0059] Specifically in this embodiment, the position detection device detects the minimum distance between the fan blade and the fan tower. Meanwhile, the position detection device used in this embodiment is a prior art, such as a photoelectric position sensor, etc., which will not be described in detail here.

[0060] That is to say, in this embodiment, the connection component specifically realizes the connection between the main blade 11 and the tail blade 12 by inserting the fixing member 133 into the first limiting hole and the second limiting hole. Among them, the fixing member 133 can be separated from the second limiting hole by setting the elastic member 134. At the same time, a position detection device is set so that during the operation of the fan blade 1, the connection component can detect the distance between the fan blade 1 and the tower, and control the limiting device according to the distance. Specifically, when the distance between the fan blade 1 and the fan tower is not less than the threshold value corresponding to the detection point, the pin is limited to the first limiting hole and the second limiting hole by the limiting device, so that the main blade 11 and the tail blade 12 remain in a connected state. When the distance between the fan blade 1 and the fan tower is less than the threshold value corresponding to the detection point, the limiting device releases the restriction on the fixing member 133, so that the fixing member 133 is separated from the second limiting hole under the action of the elastic member 134, so that the main blade 11 and the tail blade 12 cannot maintain a connected state.

[0061] Of course, in other embodiments, the second limiting hole can also be set to other structural forms in the prior art that can limit the freedom of the fixing part to move in a direction away from the first limiting hole. For example, the second limiting hole can be set to a through hole. In this case, a protrusion can be set on the inner circumferential side surface of the second limiting hole, and the compression of the elastic part can be achieved by the abutment between the protrusion and the elastic part, which will not be repeated here.

[0062] Furthermore, in the present embodiment, since the main blade 11 is still intact, when repairing the fan blade 1, it is only necessary to reinstall the new tail blade 12 without replacing the entire fan blade 1, and the material cost for the repair is relatively low. In addition, the tail blade 12 is relatively short and lower to the ground, so a large-tonnage main crane is not required for repair, and only a 100t truck crane is required. The mechanical cost for repairing the fan blade 1 will be further reduced, and the repair period will be greatly reduced, thereby reducing the normal power generation loss of the fan caused by repair.

[0063] At the same time, since the main blade 11 and the tail blade 12 are connected by the first connecting member 131 and the second connecting member 132, the first connecting member 131 and the second connecting member 132 have a certain length along the length direction of the fan blade 1, ensuring that the connection between the main blade 11 and the tail blade 12 can withstand a certain shear force and bending moment, thereby preventing the fan blade 1 from bending at the connection between the main blade 11 and the tail blade 12.

[0064] Of course, in other embodiments, the detachable connection between the main blade and the tail blade can also be achieved through other connecting components in the prior art, or in more embodiments, the first connecting member can be set on the tail blade and the second connecting member can be set on the main blade, which will not be repeated here.

[0065] Specifically in this embodiment, Figure 2-Figure 4 As shown, the first connecting member 131 is a first connecting ring, and the first connecting ring matches the cross-sectional shape of the thicker position of the main blade, and is rounded near the thinner position of the main blade; the second connecting ring matches the cross-sectional shape of the tail blade, and the second connecting ring matches the cross-sectional shape of the thicker position of the tail blade, and is rounded near the thinner position of the tail blade. The inner peripheral side surface of the second connecting ring abuts against the outer peripheral side surface of the first connecting ring. By setting the first connecting member 131 and the second connecting ring to be annular, and matching the shapes of the first connecting ring and the second connecting ring with the cross-sectional shape of the thicker position of the blade, the connection between the first connecting member 131 and the main blade and the connection between the second connecting member 132 and the tail blade are more reliable.

[0066] Of course, in other embodiments, the first connector and the second connector may also be block-shaped or sheet-shaped connectors that meet the connection strength requirements. When the first connector or the second connector is a block-shaped or sheet-shaped connector, the inner surface and the outer surface of the second connector of the first connector are distinguished in the following manner: a vertical line is drawn through the center of the connection position of the main blade and the tail blade to connect the first connector and the second connector, and the side surface that the vertical line passes through first is the inner surface, and the side surface that the vertical line passes through later is the outer surface.

[0067] Specifically in this embodiment, the fixing member 133 is a rectangular latch.

[0068] Of course, in other embodiments, the fixing member may also be a part with a relatively smooth peripheral surface to facilitate separation from the second limiting hole, such as a round pin or a nail, etc., which will not be described in detail here.

[0069] Specifically in this embodiment, Figure 5 and Figure 6 As shown, the limiting device includes an airbag 135, a blasting device (not shown in the figure) and a controller (not shown in the figure). The airbag 135 abuts against one end of the fixing member 133 relatively close to the first limiting hole. The airbag 135 is filled with nitrogen, and its gas pressure can prevent the fixing member 133 from popping out of the hole of the fixing member 133. The blasting device is arranged on the airbag 135 for detonating the airbag 135. The position detection device and the controller are arranged at the bottom of the cabin. The controller is connected to the blasting device and the position detection device respectively. The controller is used to obtain the distance detected by the position detection device, and control the blasting device to detonate the airbag 135 when the distance is less than the threshold. By using the airbag 135 to limit the fixing member 133, and using the controller and the blasting device to control whether the airbag 135 explodes or not, the structure of the airbag 135 is light, the burden on the fan blade 1 is light, and the overall structure is simple and reliable.

[0070] Specifically, during the operation of the fan blade 1, the position detection device detects the distance between the fan blade 1 and the fan tower, and sends a detection signal to the controller, and the controller explodes the device according to the detection signal. Specifically, when the position detection device detects that the distance between the fan blade 1 and the fan tower is not less than the threshold value, the controller does not send a signal to the blasting device, and the blasting device does not detonate the airbag 135, so that the airbag 135 that remains inflated can resist the fixing member 133, and the main blade 11 and the tail blade 12 are kept in a connected state through the fixing member 133. When the position detection device detects that the distance between the fan blade 1 and the fan tower is less than the threshold value, the controller sends a signal to the blasting device, controls the blasting device to detonate the airbag 135, and the outer side of the fixing member 133 loses the limit of the airbag 135, and is pushed by the elastic member 134 to break away from the second limit hole, so that the main blade 11 and the tail blade 12 lose connection, and the tail blade 12 is separated from the main blade 11. Of course, in other embodiments, other solutions existing in the prior art may be adopted to enable the latch to disengage from the second limiting hole when the distance between the wind turbine blade 1 and the wind turbine tower is too close, so that the tail blade 12 falls off, which will not be described in detail here.

[0071] In this embodiment, if Figure 5As shown, the position detection device is electrically connected to the controller via a signal line 14, and the controller is electrically connected to the blasting device via a signal line 14, wherein the signal line 14 connected to the blasting device is connected to the controller via a slip ring in the cabin to prevent the continuous rotation of the fan blades from causing the signal line 14 to twist, thereby realizing signal transmission between the position detection device, the controller, and the blasting device. Of course, in other embodiments, the position detection device, the controller, and the blasting device can also transmit signals through other methods such as wireless transmission, which will not be repeated here.

[0072] In this embodiment, if Figure 2 , Figure 3 and Figure 4 As shown, the overall shape of the first connecting member 131 and the second connecting member 132 is substantially the same as the cross-sectional shape of the fan blade 1. Specifically, the overall shape of the first connecting member 131 and the second connecting member 132 matches the cross-sectional shape of the thicker portion of the fan blade 1, and a circular arc transition is used at the trailing edge of the blade. In this embodiment, the outer diameter of the first connecting member just matches the inner diameter of the second connecting ring, and the lengths of the two also match each other.

[0073] Specifically, the cross section of the first connecting member 131 is L-shaped, and a portion of the first connecting member 131 protrudes relative to the main blade 11 toward the tail blade 12. The root of the first connecting member 131 is 15 cm thick and 30 cm long, and the length of the extended portion is 40 cm and 5 cm thick. The cross section of the second connecting member 132 is rectangular, 40 cm long, and 10 cm thick, that is, the outer diameter of the extended portion of the L-shaped first connecting member just matches the inner diameter of the second connecting ring, and the length of the extended portion of the first connecting member matches the length of the second connecting member, so that the outer peripheral side of the extended portion of the first connecting member abuts against the inner peripheral side of the second connecting member. The second connecting member 132 is arranged at the end of the tail blade 12 close to the main blade 11, so that after the main blade 11 and the tail blade 12 are aligned, a rectangular space is formed between the first connecting member 131 and the tail blade 12, the first connecting member 131 is just located in the rectangular space, the outer peripheral side of the protruding part of the second connecting member 132 relative to the main blade 11 is abutted with the inner peripheral side of the second connecting member 132, and the cross section of the connecting ring formed as a whole after the first connecting member 131 and the second connecting member 132 abut is a rectangle, the width of the rectangle is the thickness of the connecting ring, which is 15cm, and the length of the rectangle is the total width of the first connecting member 131, which is 70cm. In addition to being able to connect the main blade 11 and the tail blade 12, the connecting ring can further improve the ability of the connection between the main blade 11 and the tail blade 12 to withstand shear force and bending moment by setting the cross section of the first connecting member to an L-shape to match the first connecting member.

[0074] Of course, in other embodiments, the overall shape of the first connecting ring and the second connecting ring may also be circular, elliptical, etc. The closer the overall shape of the first connecting ring and the second connecting ring is to the shape of the fan cross section, the higher the fit between the first connecting ring and the second connecting ring and the fan blade, and the more reliable the connection, which will not be elaborated here.

[0075] Specifically, in the present embodiment, the first connecting member 131 and the main blade 11 are integrally formed, and the second connecting member 132 and the tail blade 12 are integrally formed. By integrally forming the first connecting member 131 and the main blade 11, and integrally forming the second connecting member 132 and the tail blade 12, on the one hand, the connection between the first connecting member 131 and the main blade 11, and the connection between the second connecting member 132 and the tail blade 12 can be made more reliable, and on the other hand, it is not necessary to punch holes in the main blade 11 and the tail blade 12, and the detachable connection between the main blade 11 and the tail blade 12 can be achieved without affecting the structural strength of the main blade 11 and the tail blade 12.

[0076] Of course, in other embodiments, the first connecting ring and the fan blade, and the second connecting ring and the fan blade may also be connected in other ways.

[0077] In this embodiment, the first limiting hole and the second limiting hole extend along the normal direction of the outer peripheral side surface of the first connecting ring, and the airbag 135 is arranged inside the inner peripheral side surface of the first connecting ring. In other words, the first connecting ring is sleeved on the outside of the airbag 135, and the fixing member 133 is perpendicular to the outer peripheral side surface of the second connecting ring. Since the outer peripheral side surface of the first connecting ring is a curved surface, the normal direction of the outer peripheral side of the first connecting ring mentioned here refers to the normal direction of the tangent plane at the intersection of the axis of the first limiting hole and the outer peripheral side surface of the first connecting ring.

[0078] In other embodiments, when the first connecting member and the second connecting member are block-shaped or sheet-shaped connecting members, the first limiting hole extends along the normal direction of the plane where the outer surface of the first connecting ring is located.

[0079] In this embodiment, the fixing member 133 is a rectangular steel plate latch, and the length of the fixing member 133 is about 5 cm less than the sum of the lengths of the first limiting hole and the second limiting hole, that is, the length of the fixing member 133 is 10 cm, the width is 199 mm, and the thickness is 39 mm. The elastic member 134 is compressed in the second limiting hole, and along the expansion and contraction direction of the elastic member 134, the two ends of the elastic member 134 are respectively in contact with the bottom wall of the second limiting hole and the fixing member 133. Specifically in this embodiment, the elastic member 134 is a coil spring. By compressing the coil spring in the second limiting hole, a force is applied to the fixing member 133 to disengage from the second limiting hole, and the structure is simple and reliable.

[0080] Of course, in other embodiments, the latch may also be a steel cylinder, and the specific size of the latch may also be adjusted according to the specific size of the first connecting ring and the second connecting ring, which will not be described in detail here.

[0081] Specifically in the present embodiment, there are eight second limiting holes and eight first limiting holes, and the eight second limiting holes and the plurality of first limiting holes are arranged in one-to-one correspondence. At the same time, the number of the fixing members 133 is also eight, and the eight fixing members 133 are respectively arranged in the one-to-one corresponding first limiting holes and second limiting holes. Further, the eight first limiting holes and the eight second limiting holes are evenly arranged on the first connecting member 131 and the second connecting member 132 along the circumference of the first connecting member 131 and the second connecting member 132. By setting a plurality of first limiting holes and a plurality of second limiting holes, and evenly arranging these first limiting holes, the connection between the first connecting member 131 and the second connection is more reliable.

[0082] Of course, in other embodiments, the number of the first limiting holes and the second limiting holes can be adaptively adjusted according to the size of the blade and the size of the first connecting ring and the second connecting ring. When the number of the first limiting holes and the second limiting holes are both set in multiple numbers, the first connecting ring and the second connecting ring are relatively reliable, which will not be repeated here.

[0083] Specifically in the present embodiment, the length L of the fan blade 1 is 90m, and the length a of the tail blade 12 is 5m, then the length of the tail blade 12 is about 5% of the length of the entire fan blade 1. When there is a risk of the fan blade 1 sweeping the tower, after the tail blade 12 actively separates from the main blade 11 at a length of about 5m at the tip of the fan blade 1, the fan blade 1 will basically no longer sweep the tower.

[0084] Of course, in other embodiments, the length of the tail blade can be adjusted according to the actual situation according to the size of the fan blade. Generally speaking, the length of the tail blade should account for about 5% to 15% of the total length of the fan blade. When the fan blade is at risk of sweeping the tower, the tail blade can be separated from the main blade to avoid the situation.

[0085] Example 2

[0086] The present embodiment provides a method for preventing the blades of a fan from being swept, which comprises the following steps: dividing the fan blades into main blades close to the main unit of the fan and tail blades far away from the main unit of the fan along the axial direction of the blades, and connecting the main blades and the tail blades through a connecting component; detecting the distance between the fan blades and the fan tower, and if the distance is less than a threshold, sending a control signal to the connecting component, and the connecting component controls the tail blades to be separated from the main blades. By connecting the main blades and the tail blades through the connecting component, the distance between the fan blades and the fan tower is detected during the operation of the fan blades. If the distance is detected to be less than the threshold, it indicates that the fan blades are at risk of sweeping the fan tower. At this time, by sending a control signal to the connecting component, the connecting component controls the tail blades to be separated from the main blades, thereby preventing the fan blades from sweeping the fan tower, reducing the degree of damage to the fan and the economic loss, and reducing the difficulty of subsequent repair work. Specifically in the present embodiment, the detected distance is the minimum distance between the fan blades and the fan tower, wherein the minimum distance is the minimum value of the horizontal distance between the fan blades and the fan tower. Furthermore, the minimum distance is the minimum value of the distance from the closest point of the wind turbine blade to the wind turbine tower to the axis of the wind turbine tower.

[0087] For example, in this embodiment, a position detection device is arranged at the bottom of the nacelle of the wind turbine, the length of the wind turbine blade is 90m, and the threshold value is set to 0.9m. When the position detection device detects that the minimum value of the distance from the wind turbine blade to the axis center of the wind turbine tower is 0.9m or 1m at a certain moment, there is no need to send a control signal to the connecting component to control the tail blade to separate from the main blade; when the position detection device detects that the minimum value of the distance from the wind turbine blade to the axis center of the wind turbine tower is 0.88m at a certain moment, a control signal is sent to the connecting component, and the connecting component controls the tail blade to separate from the main blade to avoid the accident of the wind turbine blade sweeping the tower.

[0088] Of course, in other embodiments, the threshold value can be set according to the actual situation of the blade and the measurement method of the minimum distance, and the minimum distance from the fan blade to the fan tower also has multiple detection points, such as measuring the horizontal distance from the closest point of the fan blade to the fan tower to the outer peripheral wall of the fan tower, etc. In other words, the threshold value will also change according to different detection points, and the selection or calculation method of the threshold value is a prior art and will not be repeated here.

[0089] Although the specific embodiments of the present invention are described above, it should be understood by those skilled in the art that this is only for illustration and the protection scope of the present invention is defined by the appended claims. Those skilled in the art may make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but these changes and modifications all fall within the protection scope of the present invention.

Claims

1. A fan blade, characterized in that: The fan blades include a main blade close to the fan main unit, a tail blade far away from the fan main unit, and a connecting assembly, and the main blade and the tail blade are detachably connected through the connecting assembly; The fan blade further comprises a position detection device, wherein the position detection device is used to detect the distance between the fan blade and the fan tower; The connection assembly is capable of releasing the connection between the main blade and the tail blade when the distance is less than a threshold value.

2. The fan blade according to claim 1, characterized in that: The connection component comprises: A first connecting member and a second connecting member, wherein the first connecting member and the second connecting member are respectively arranged on the main blade and the tail blade, the second connecting member is arranged and sleeved on the outer peripheral side of the first connecting member, the inner side surface of the second connecting member and the outer side surface of the first connecting member abut against each other, the first connecting member has a first limiting hole, the second connecting member has a second limiting hole, and the first limiting hole and the second limiting hole are arranged correspondingly; A fixing member, wherein two ends of the fixing member are respectively inserted into the first limiting hole and the second limiting hole which are correspondingly arranged, and the structure of the second limiting hole is arranged to limit the freedom of the fixing member to move in a direction away from the first limiting hole; an elastic member, the elastic member being used to exert a force on the fixing member to move toward the first limiting hole and away from the second limiting hole; A limiting device is used to limit the fixing member from being separated from the second limiting hole, and can release the limitation on the fixing member when the distance is less than a threshold value.

3. The fan blade according to claim 2, characterized in that: The limiting device comprises: an airbag, the airbag abutting against an end of the fixing member relatively close to the first limiting hole, so as to limit the fixing member from being separated from the second limiting hole; An explosive device, the explosive device is used to detonate the airbag; A controller is connected to the blasting device and the position detection device respectively, and is used to obtain the distance detected by the position detection device and control the blasting device to detonate the airbag when the distance is less than a threshold value.

4. The fan blade according to claim 3, characterized in that: The first limiting hole and the second limiting hole extend along the normal direction of the outer surface of the first connecting member, and the airbag is arranged inside the inner surface of the first connecting member.

5. The fan blade according to claim 2, characterized in that: The first connecting member is disposed on the main blade and is integrally formed with the main blade; and / or: The second connecting member is arranged on the tail blade and is integrally formed with the tail blade.

6. The fan blade according to any one of claims 2 to 5, characterized in that: The elastic member is compressed in the second limiting hole, and along the expansion and contraction direction of the elastic member, two ends of the elastic member are respectively in contact with the bottom wall of the second limiting hole and the fixing member.

7. The fan blade according to any one of claims 2 to 5, characterized in that: The number of the second limiting holes and the number of the first limiting holes are both plural, and the second limiting holes and the first limiting holes are arranged in a one-to-one correspondence, and the fixing piece is inserted into at least one of the correspondingly arranged second limiting holes and the first limiting holes.

8. The fan blade according to any one of claims 2 to 5, characterized in that: The first connecting member is a first connecting ring, and the second connecting member is a second connecting ring. The inner peripheral side surface of the second connecting ring abuts against the outer peripheral side surface of the first connecting ring.

9. The fan blade according to any one of claims 2 to 5, characterized in that: The fixing member comprises a rectangular latch.

10. The fan blade according to any one of claims 2 to 5, characterized in that: The length of the fan blade is L, the length of the tail blade is a, and 0.05L≤a≤0.15L.

11. A fan, characterized in that: The wind turbine comprises: a wind turbine tower; A fan blade as claimed in any one of claims 1 to 10.

12. The fan according to claim 11, characterized in that The wind turbine further comprises a nacelle, and the position detection device is arranged at the bottom of the nacelle.

13. A method for preventing fan blades from being swept, characterized in that: It includes the following steps: The fan blades are divided into main blades close to the fan main unit and tail blades far away from the fan main unit along the blade axis, and the main blades and the tail blades are connected by a connecting component; The distance from the wind turbine blade to the wind turbine tower is detected. If the distance is less than a threshold value corresponding to the detected point, a control signal is sent to the connection component, and the connection component controls the tail blade to separate from the main blade.

14. The fan blade anti-sweep method according to claim 13, characterized in that: The distance is the minimum value of the horizontal distance from the fan blades to the fan tower.

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