Wind power blade fatigue testing device

Abstract

An embodiment of the utility model provides a wind power blade fatigue testing device which comprises a winding rope and a pulling rope, one end of the pulling rope is fixedly connected with a fixed pulley, the other end of the pulling rope is fixedly connected with a calibration support, the calibration support is fixed on the ground, and the winding rope is fixed on the fixed pulley. One end of the winding rope is fixedly connected with a take-up mechanism used for tightening the winding rope, the take-up mechanism is fixed over the fixed pulley, the winding rope penetrates through the fixed pulley, the end, away from the take-up mechanism, of the winding rope is fixedly connected with a force sensor, and the end, away from the winding rope, of the force sensor is fixedly connected to the tested fan blade. Aiming at an existing fatigue test static calibration mode, an original loading electric hoist transverse pulling mode is changed into a vertical direction use mode, an original loading electric hoist hanging mode is changed into a joist barrow hanging mode from a crane hanging mode, and the upper limit of calibration loading force is improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of wind turbine blade testing, and in particular relates to a wind turbine blade fatigue testing device. Background Art

[0002] During the fatigue test of wind turbine blades, static calibration of the blades is required to confirm the relationship between the strain value and the test load during the test, so as to determine whether the blade fatigue test meets the test load requirements. Currently, static calibration during the blade fatigue test is basically performed by fixing the blade with a crane and loading it horizontally with an electric hoist.

[0003] As the length of wind turbine blades has exceeded 120m, the large-scale blades require a greater loading force for static calibration. The current loading method uses a 50T crane as a fixed support, and its maximum loading force is only 50kN. If a larger calibration loading force is required, a larger tonnage crane is required as a fixed support. Moreover, the horizontal pulling loading method of the crane or electric hoist is contrary to its designed working method, which poses a safety risk during the use of the equipment. Utility Model Content

[0004] In view of the above problems existing in the prior art, an object of the embodiments of the present utility model is to provide a wind turbine blade fatigue testing device.

[0005] The technical solution adopted in the embodiment of the utility model is a wind turbine blade fatigue testing device, including a winding rope and a traction rope, one end of the traction rope is fixedly connected to a fixed pulley, the other end of the traction rope is fixedly connected to a calibration bracket, the calibration bracket is fixed on the ground, one end of the winding rope is fixedly connected to a take-up mechanism for tightening the winding rope, the take-up mechanism is fixed directly above the fixed pulley, the winding rope passes through the fixed pulley, and the end of the winding rope away from the take-up mechanism is fixedly connected to a force sensor, and the end of the force sensor away from the winding rope is fixedly connected to the wind blade under test.

[0006] Furthermore, a fixing mechanism is installed at one end of the force sensor away from the rope winding, and the fixing mechanism is used to fix the force sensor to the wind blade under test.

[0007] Furthermore, the fixing mechanism is a sling or a clamp.

[0008] Furthermore, the calibration bracket includes a base and a pull rod, a long pin is movably installed on one end of the top of the base, and the base is movably connected to one end of the pull rod through the long pin, the pull rod can rotate with the long pin as the axis, and a plurality of fixing holes are sequentially opened on the pull rod along the length direction, and the fixing holes are used to fix one end of the traction rope away from the fixed pulley.

[0009] Furthermore, a support frame is movably mounted on one end of the top of the base away from the long latch, and the support frame can rotate with the connection point between the support frame and the base as an axis, and the free end of the support frame can support the pull rod.

[0010] Furthermore, it also includes a pin, which can be inserted into the fixing hole, and the pin is used to fix the end of the traction rope away from the fixed pulley to the fixing hole.

[0011] Furthermore, a plurality of guide rail grooves are provided on the ground, bolts are installed in the guide rail grooves, and the bolts can move along the guide rail grooves. A connecting piece is fixedly connected to the side wall of the calibration bracket, and a U-shaped groove matching with the bolt is opened on the connecting piece. When fixing the calibration bracket, the bolt is placed in the U-shaped groove and locked.

[0012] Compared with the prior art, the utility model aims at the existing fatigue test static calibration method, changes the original horizontal pulling mode of the loading electric hoist to vertical use, and changes the original loading electric hoist from crane suspension to gantry suspension, thereby increasing the upper limit of the calibration loading force.

[0013] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not intended to restrict the present invention.

[0014] The overview of various implementations or examples of the technology described in this utility model is not a comprehensive disclosure of the entire scope or all features of the disclosed technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In the drawings that are not necessarily drawn to scale, the same reference numerals may describe similar parts in different views. The same reference numerals with letter suffixes or different letter suffixes may represent different instances of similar parts. The accompanying drawings generally illustrate various embodiments by way of example and not limitation, and together with the specification and claims, are used to illustrate the embodiments of the utility model. When appropriate, the same reference numerals are used in all drawings to refer to the same or similar parts. Such embodiments are illustrative and are not intended to be exhaustive or exclusive embodiments of the present device or method.

[0016] Figure 1 It is a schematic structural diagram of an embodiment of the utility model.

[0017] Figure 2 This is a schematic diagram of the calibration bracket structure of an embodiment of the utility model.

[0018] Figure 3 This is a schematic diagram of a static calibration scheme for fatigue testing according to an embodiment of the utility model.

[0019] Figure 4 It is a measurement and calculation schematic diagram of an embodiment of the utility model. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution of the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings of the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. Based on the described embodiment of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0021] Unless otherwise defined, the technical terms or scientific terms used in the present invention shall have the usual meanings understood by persons with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Words such as "include" or "comprise" and the like mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Words such as "connect" or "connected" and the like are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0022] In order to keep the following description of the embodiments of the present invention clear and concise, the present invention omits detailed descriptions of known functions and known components.

[0023] See also Figures 1 to 4 The embodiment of the utility model provides a wind turbine blade fatigue test device, including a rope 5 and a traction rope 2, one end of the traction rope 2 is fixedly connected to a fixed pulley 3, the other end of the traction rope 2 is fixedly connected to a calibration bracket 1, the calibration bracket 1 is fixed on the ground, one end of the rope 5 is fixedly connected to a take-up mechanism 4 for tightening the rope 5, the take-up mechanism 4 is fixed just above the fixed pulley 3, the rope 5 passes through the fixed pulley 3, and the end of the rope 5 away from the take-up mechanism 4 is fixedly connected to a force sensor 6, and the end of the force sensor 6 away from the rope 5 is fixedly connected to the wind blade under test. Aiming at the existing fatigue test static calibration method, the utility model changes the original horizontal pulling method of the loading electric hoist to vertical use, and changes the original loading electric hoist from crane suspension to gantry suspension, thereby increasing the upper limit of the calibration loading force.

[0024] This technical solution is designed using the parallelogram rule of composite force and the principle of changing the direction of force by a fixed pulley. By using the principle of changing the direction of force by the fixed pulley 3, the horizontal calibration loading force F1 required for static calibration is changed to the vertical electric hoist force F2 of the same magnitude, and the angle between the two forces is 90°. Then, by using the parallelogram rule of composite force, the traction rope of the fixed pulley 3 is arranged in the opposite direction of the composite force F of the loading reaction force F1 and the electric hoist force F2, so that the force F3 of the traction rope is balanced with the composite force of the two forces F1 and F2. In the process of adjusting the loading force by static calibration, the two forces F1 and F2 change synchronously but the direction of the composite force does not change. In this way, the requirement of static calibration of fatigue test for constant application of loading force in horizontal direction is achieved (see Figure 3 ). Similarly, in some special requirements for the loading force angle direction (non-horizontal), the solution can also adjust the angle between F1 and F2 to meet the requirements of the special loading angle.

[0025] The end of the force sensor 6 away from the rope 5 is equipped with a fixing mechanism 7, and the fixing mechanism 7 is used to fix the force sensor 6 to the tested wind blade. In order to cope with different installation sites, the fixing mechanism 7 can choose to use a sling or a clamp to fix the force sensor 6 to the tested wind blade.

[0026] In order to meet the testing needs of blades of different models and different blade heights, a set of calibration bracket fixtures for the static calibration method is designed. The calibration bracket fixture can meet the static calibration of blades with different cross-sections and different height positions by adjusting the hole positions, and at the same time ensure that the direction of the loading force remains horizontal during the static calibration process. The calibration bracket 1 includes a base 13 and a pull rod 11. A long pin 15 is movably installed at one end of the top of the base 13, and the base 13 is movably connected to one end of the pull rod 11 through the long pin 15. The pull rod 11 can rotate with the long pin 15 as the axis. A plurality of fixing holes 16 are sequentially opened on the pull rod 11 along the length direction. The fixing hole 16 is used to fix the end of the traction rope 2 away from the fixed pulley 3. The fixing holes 16 are numbered n in sequence from the constraint end of the pull rod 11 to the free end.

[0027] See also Figure 4 After the blade is installed on the test bench according to the requirements of the blade fatigue test, the height H of the blade's calibrated loading point from the ground is measured: when there is no fixture at the blade loading point, the height from the ground at the trailing edge of the blade is measured; when there is a fixture at the blade loading point, the height from the ground at the center of the blade fixture is measured.

[0028] Calculate the total length L of the traction rope and the starting point of the calibration bracket according to the height H:

[0029] L=(H-225) / sin45°=1.414*(H-225)

[0030] n=(Ll-180) / 141.4=(1.414*(H-225)-l-180) / 141.4

[0031] ≈0.01H-(l / 141.4)-3.5 (rounded to the nearest integer 0≤n≤20)

[0032] There are three specifications for the length l of the traction rope: when 5301mm<H≤7400mm, l=7070mm; when 7400mm<H≤9400mm, l=9898mm; when 9400mm<H≤11400mm, l=12726mm;

[0033] During the on-site calibration process, the length l of the traction rope and the number n of the bracket installation hole are calculated and selected according to the blade loading point height H to meet the loading requirements of different blade heights.

[0034] ——H is the height of the blade’s calibrated loading point from the ground (unit: mm)

[0035] ——L is the total length of the traction rope and the starting point of the calibration bracket (unit: mm)

[0036] ——a is the height of the blade calibration loading point from the calibration bracket starting point (unit: mm)

[0037] ——b is the length of the rope from the fixed pulley to the force sensor (unit: mm)

[0038] ——l is the length of the traction rope (unit: mm)

[0039] ——n is the hole number of the calibration bracket

[0040] ——h is the height corresponding to the hole number of the calibration bracket (unit: mm)

[0041] ——180 is the length of the shackle, that is, the distance from the traction rope to the center of the fixed pulley is 180mm

[0042] ——225 is the height of the calibrated bracket starting point from the ground, 225mm

[0043] Where: a = H-225;

[0044] b≥1.5 times the blade deformation;

[0045] h=100*n.

[0046] A support frame 14 is movably mounted on one end of the top of the base 13 away from the long bolt 15. The support frame 14 can rotate around the connection point between the support frame 14 and the base 13. The free end of the support frame 14 can support the pull rod 11. The support frame 14 is used to support the pull rod 11 when in use for easy operation.

[0047] It also includes a latch 12, which can be inserted into the fixing hole 16, and the latch 12 is used to fix the end of the traction rope 2 away from the fixed pulley 3 to the fixing hole 16. The traction rope 2 is fixed on the latch 12, and the latch 12 is then inserted into the fixing hole 16, so there is no need to insert the traction rope 2 into the fixing hole 16, which is conducive to conveniently fixing the traction rope 2.

[0048] A plurality of guide rail grooves 9 are provided on the ground, and bolts are installed in the guide rail grooves 9, and the bolts can move along the guide rail grooves 9. A connector 17 is fixedly connected to the side wall of the calibration bracket 1, and a U-shaped groove 18 is provided on the connector 17 to cooperate with the bolts. When the calibration bracket 1 is fixed, the bolts are placed in the U-shaped groove 18 and locked. The guide rail groove 9 is conducive to conveniently fixing the calibration bracket 1 on the one hand, and is convenient for adjusting the position of the calibration bracket 1 on the other hand, so that the fixed pulley 3 is directly below the take-up mechanism 4.

[0049] The blade 8 under test is fixed by a fixing mechanism 7, a force sensor 6 is installed on the loading side, and then connected to the hook of the take-up mechanism 4 (such as an electric hoist) through a rope 5 passing through the fixed pulley 3. The calibration bracket 1 is fixed on the guide groove 9 of the test bench, one end of the traction rope 2 is fixed on the calibration bracket 1, and the other end is connected to the fixed pulley 3. The height of the hole of the calibration bracket 1 and the length of the traction rope 2 are adjusted to adapt to blades of different heights. The rope is slightly tightened by adjusting the gantry or electric hoist 4. When the blade end of the rope is kept horizontal and the end of the electric hoist 4 is kept vertical, the static calibration operation of the blade 8 can be performed.

[0050] The above description is intended to be illustrative rather than restrictive, and those skilled in the art may make changes, modifications, substitutions and variations to the above embodiments within the scope of the present disclosure. Moreover, the above examples (or one or more of them) may be used in combination with each other, and it is contemplated that these embodiments may be combined with each other in various combinations or permutations.

Claims

1. A wind turbine blade fatigue testing device, comprising a winding rope (5) and a traction rope (2), characterized in that: One end of the traction rope (2) is fixedly connected to a fixed pulley (3), and the other end of the traction rope (2) is fixedly connected to a calibration bracket (1), and the calibration bracket (1) is fixed on the ground. One end of the winding rope (5) is fixedly connected to a take-up mechanism (4) for tightening the winding rope (5), and the take-up mechanism (4) is fixed directly above the fixed pulley (3). The winding rope (5) passes through the fixed pulley (3), and one end of the winding rope (5) away from the take-up mechanism (4) is fixedly connected to a force sensor (6), and one end of the force sensor (6) away from the winding rope (5) is fixedly connected to the wind blade under test.

2. A wind turbine blade fatigue testing device according to claim 1, characterized in that: A fixing mechanism (7) is installed at one end of the force sensor (6) away from the rope (5), and the fixing mechanism (7) is used to fix the force sensor (6) to the wind blade under test.

3. A wind turbine blade fatigue testing device according to claim 2, characterized in that: The fixing mechanism (7) is a sling or a clamp.

4. A wind turbine blade fatigue testing device according to any one of claims 1 to 3, characterized in that: The calibration bracket (1) comprises a base (13) and a pull rod (11), a long pin (15) is movably mounted on one end of the top of the base (13), and the base (13) is movably connected to one end of the pull rod (11) via the long pin (15), and the pull rod (11) can rotate around the long pin (15), and a plurality of fixing holes (16) are sequentially provided on the pull rod (11) along the length direction, and the fixing hole (16) is used to fix one end of the traction rope (2) away from the fixed pulley (3).

5. A wind turbine blade fatigue testing device according to claim 4, characterized in that: A support frame (14) is movably mounted on one end of the top of the base (13) away from the long latch (15); the support frame (14) can rotate with the connection point between the support frame and the base (13) as an axis, and the free end of the support frame (14) can support the pull rod (11).

6. A wind turbine blade fatigue testing device according to claim 4, characterized in that: It also comprises a latch (12), which can be inserted into the fixing hole (16) and is used to fix one end of the traction rope (2) away from the fixed pulley (3) to the fixing hole (16).

7. A wind turbine blade fatigue testing device according to claim 1, characterized in that: A plurality of guide rail grooves (9) are provided on the ground, bolts are installed in the guide rail grooves (9), and the bolts can move along the guide rail grooves (9). A connecting piece (17) is fixedly connected to the side wall of the calibration bracket (1), and a U-shaped groove (18) is provided on the connecting piece (17) for matching with the bolts. When the calibration bracket (1) is fixed, the bolts are placed in the U-shaped groove (18) and locked.

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