Wind power blade strength prediction equipment and prediction method thereof

Abstract

The invention discloses wind power blade strength prediction equipment and a prediction method thereof, and belongs to the technical field of blade fatigue test.The wind power blade strength prediction equipment comprises a test piece supporting mechanism used for being fixedly connected with the blade root of a blade test piece and a movable blade tool fixed to the outer side of the blade test piece; the movable blade tool comprises a supporting frame, a distance adjusting assembly, a lateral supporting assembly and a self-adaptive supporting assembly, and by means of the mode, the movable blade tool can adapt to blade test pieces with different widths and different thicknesses and can move in the length direction of the movable blade tool after being installed on the blade test pieces; the strength of each point position of the blade test piece is detected, so that multi-point-position force application detection of the blade test piece is realized, potential defects such as layering and micro-cracks of each area are actively excited through comprehensive analysis of data of each point position, and a blind area of single loading point test is avoided, so that a more real and practical simulation effect is realized; and the accuracy of prediction results is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of blade fatigue testing, and particularly to a wind turbine blade strength prediction device and a prediction method thereof. Background Art

[0002] By sampling and conducting fatigue tests on wind turbine blades, the fatigue performance of wind turbine blades can be comprehensively evaluated to ensure their long-term reliability under complex wind conditions.

[0003] Chinese Patent Application CN111811965A discloses a wind turbine blade fatigue testing device and method, including: a root bracket for fixing the root of the blade; a fixed frame, which is arranged near the tip of the blade, and the side of the fixed frame facing the blade is open; a tip clamp for clamping the tip and transmitting driving force; a longitudinal driving mechanism with a longitudinal connecting rod, and the longitudinal connecting rod is arranged at the bottom of the tip clamp, and the longitudinal driving mechanism is used to drive the tip clamp to reciprocate in the vertical direction; a transverse driving mechanism with a transverse connecting rod, and the transverse connecting rod is arranged on the side of the tip clamp, and the transverse driving mechanism is used to drive the tip clamp to reciprocate in the horizontal direction; through the driving of the tip clamp and the transverse driving mechanism and the longitudinal driving mechanism, the blade makes an elliptical motion on the plane where the cross-section is located, which not only simulates the up-and-down swing of the blade, but also simulates the wind blowing direction and torsional deformation during the actual operation of the blade. However, this device still has the following problems: 1. There are differences in the strength of the blade in different regions. During fatigue testing, it is necessary to dynamically apply force and control the load at multiple points on the blade, so that the operator needs to continuously climb up to disassemble and assemble the tooling to change the position of the tooling on the blade. At the same time, the size of the blade tooling is usually fixedly set. When clamping and fixing different models of blades and different positions of the same model of blades, it is necessary to re-manufacture the profiling mold, which not only increases the test cost, causes waste in the control of unused tooling, but also increases the time used for fatigue testing; 2. When the blade is undergoing fatigue testing, it is necessary to dynamically apply force in the flapping direction and the pitching direction, and two sets of driving structures are required to control respectively, which not only increases the test cost, but also is inconvenient to control the composite motion trajectory of the blade in two directions during the actual operation process.

[0004] Based on this, the present invention designs a wind turbine blade strength prediction device and a prediction method thereof to solve the above problems. Summary of the Invention

[0005] In view of the above-mentioned drawbacks of the prior art, the present invention provides a wind turbine blade strength prediction device and a prediction method thereof.

[0006] To achieve the above objectives, the present invention is realized through the following technical solutions: A wind turbine blade strength prediction device includes a specimen support mechanism for fixedly connecting with the blade root of a blade specimen and a mobile blade tooling fixed on the outer side of the blade specimen. The mobile blade tooling includes a support frame, a spacing adjustment component, a lateral support component, and an adaptive support component. Two support frames are symmetrically arranged on the upper and lower sides of the blade specimen. A moving component is arranged in the middle of the support frame, and the moving component is used to drive the support frame to move along the length direction of the blade specimen. Adaptive support components are symmetrically arranged on both sides of the support frame, and the adaptive support components are used to fit with the upper and lower outer walls of the blade specimen so that the support frame remains horizontal on the blade specimen. A spacing adjustment component is arranged between the two ends of the two support frames, and the spacing adjustment component is used to adjust the spacing between the upper and lower support frames. A lateral support component is also arranged at the mobile end of each support frame, and the lateral support component is used to limit the left and right outer walls of the blade specimen. A compound swing control mechanism is arranged on the lower side of the mobile blade tooling. The output end of the compound swing control mechanism is connected with the support frame. The compound swing control mechanism realizes dynamic force application to the blade specimen in the flap direction and the lead-lag direction through a single power source, and the compound swing control mechanism is fastened to the ground or a support platform.

[0007] Furthermore, the support frame is composed of two parallel cross bars and a connecting plate fixedly installed between the middle parts of the cross bars. The moving component includes a moving motor and fixed moving wheels. Two fixed moving wheels that are rotationally installed at one end of the connecting plate close to the blade specimen and are in rolling connection with the outer wall of the blade specimen are arranged. The fixed moving wheels are distributed along the length direction of the blade specimen. A moving motor is fixedly installed at the other end of the connecting plate, and the output end of the moving motor is in transmission connection with any one of the fixed moving wheels through a transmission component.

[0008] Furthermore, the adaptive support component includes a second support plate, a scissor bracket, a servo push rod, and a floating support component. Multiple second support plates are arranged and evenly distributed at equal intervals along the length direction of the blade specimen. The second support plates are in limit sliding connection with the cross bars. A floating support component that is in imitation fit with the side wall of the blade specimen is arranged on each second support plate. The servo push rod is fixedly connected with the end of the cross bar, and the output end of the servo push rod is fixedly connected with the second support plate. A scissor bracket is arranged on the second support plate, so that the second support plate can expand or contract along the length direction of the cross bar starting from the connecting plate.

[0009] Furthermore, the floating support component is composed of multiple groups of moving floating support structures and fixed floating support structures that are arranged in an alternating manner on the second support plate. The moving floating support structures are used to fit with the outer wall of the blade specimen when the support frame moves on the blade specimen to keep the support frame balanced. The fixed floating support structures are used to fit with the outer wall of the blade specimen when the support frame needs to be fixed on the outer side of the blade specimen to keep the support frame fastened to the blade specimen.

[0010] Furthermore, the fixed floating support structure includes a first push cylinder, an arc-shaped support plate and a pressure sensor. The first push cylinder is fixedly connected to the second support plate. The output end of the first push cylinder is hinged to the arc-shaped support plate, and the arc-shaped support plate is restricted by the rotation of the hinge seat so that the rotation range of the arc-shaped support plate is forty-five degrees to one hundred and thirty-five degrees; a non-slip rubber layer is provided on the arc-shaped support plate to increase friction; pressure sensors are provided at both ends of the arc-shaped support plate.

[0011] Furthermore, the mobile floating support structure includes a second push cylinder, a support roller and a pressure sensor. The second push cylinder is fixedly connected to the second support plate. The output end of the second push cylinder is equipped with a pressure sensor, and the lower end of the pressure sensor is equipped with a support roller.

[0012] Furthermore, the spacing adjustment component includes a first support plate, an adjusting motor and a rotating rod, the first support plate is slidingly connected to the cross bar, and the first support plate is fixedly connected to the outermost second support plate; the two rotating rods are rotatably connected to the first support plate on the upper support frame through bearings and are symmetrically distributed front and back, the two rotating rods are connected through a transmission assembly to achieve synchronous rotation, the lower end of the rotating rod is provided with a thread, and a screw sleeve matching the thread is fixedly installed on the first support plate of the lower support frame; the adjusting motor is fixedly connected to the first support plate, and the output end of the adjusting motor is fixedly connected to any rotating rod.

[0013] Furthermore, the lateral support assembly includes a connecting sleeve and a baffle, the connecting sleeve is rotatably mounted on the first support plate through a bearing, and the baffle is fixedly mounted between the connecting sleeves, and the baffle is used to abut against the side of the blade specimen.

[0014] Furthermore, the composite swing amplitude control mechanism includes a bracket, a longitudinal swing component, a lateral swing component, a linkage rod and a third push cylinder. The longitudinal swing component is arranged on the lower side of the blade specimen, the bracket is arranged on the left or right side of the blade specimen, and the lateral swing component is installed on the top of the bracket. The two ends of the linkage rod are respectively hinged to the moving ends of the longitudinal swing component and the lateral swing component; the third push cylinder is fixedly installed on the upper end of the bracket, and the output end of the third push cylinder is fixedly connected to the moving end of the lateral swing component; the moving ends of the longitudinal swing component and the lateral swing component are respectively connected to the bottom and side of the support frame, and are respectively used to control the swing of the blade specimen in the swing direction and the swinging direction.

[0015] In order to better achieve the purpose of the present invention, the present invention also provides a prediction method for a wind turbine blade strength prediction device, comprising the following steps: Step 1: Install strain gauges, displacement meters and accelerometers on the surface and inside of the blade specimen at set intervals along the length of the blade specimen; Step 2: Install the mobile blade tooling at the midpoint of the blade specimen. Adjust the distance between the upper and lower support frames through the spacing adjustment component so that the moving components on the two support frames always fit against the upper and lower side walls of the blade specimen to adapt to different thickness parts of the blade specimen. Step 3: Push the first support plate and the second support plate to move synchronously along the length direction of the blade specimen through the servo push rod, so that the baffles on both sides always abut against the two sides of the blade specimen to adapt to different width parts of the blade specimen. Step 4: Drive the support rollers to move vertically through the second push cylinder. When the reading of the pressure sensor at the end of the second push cylinder reaches the set value, the output end of the second push cylinder stops moving, so that each support roller fits against the outer wall of the blade specimen and the force is balanced. Control the rotation of the fixed moving wheels through the moving motor to drive the support frame to move along the length direction of the blade specimen to the force application point. Step 5: After the support frame moves to the force application point of the blade specimen, drive the arc-shaped support plate to move vertically through the first push cylinder. The arc-shaped support plate will automatically rotate after contacting the outer wall of the blade specimen, adjust its angle to make the contact area between the arc-shaped support plate and the outer wall of the blade specimen the largest, and when the readings of the pressure sensors at both ends of the arc-shaped support plate reach the set value, the output end of the first push cylinder stops moving, so that each arc-shaped support plate is evenly stressed, and further make the support frame fastened to the blade specimen. Step 6: The third push cylinder drives the transverse slide to reciprocate horizontally. The transverse slide drives the longitudinal slide to reciprocate synchronously vertically through the linkage rod. And the approaching and separating situations of the transverse slide and the blade specimen and the longitudinal slide and the blade specimen are opposite. The two are combined to realize the elliptical motion of the blade specimen; after the test is completed, the first push cylinder drives the arc-shaped support plate to reset. Step 7: Check whether the readings of the strain gauges, displacement gauges and accelerometers meet the set values. Step 8: Repeat Steps 4 to 7 until fatigue tests are carried out on multiple points at the midpoint and the tip of the blade specimen, and comprehensively judge the strength of the blade specimen through the readings of the sensors.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The mobile blade tooling can adapt to blade specimens with different widths and different thicknesses. After the mobile blade tooling is installed on the blade specimen, it can move along the length direction of the mobile blade tooling to detect the strength of each point of the blade specimen, so as to realize the multi-point force application detection of the blade specimen. Through the comprehensive analysis of the data of each point, the potential defects in each area, such as delamination, microcracks, etc., are actively excited, avoiding the blind area of single loading point testing, so as to achieve a more real and actual simulation effect and ensure the accuracy of the prediction result.

[0017] 2. Under the action of the linkage rod, when the transverse sliding table approaches the blade specimen, the longitudinal sliding table moves away from the blade specimen synchronously, and when the transverse sliding table moves away from the blade specimen, the longitudinal sliding table approaches the blade specimen synchronously. Thus, under the drive of a single power source of the third push cylinder, the swinging of the blade specimen in the flapping direction and the pitch direction can be controlled. The combination of the two realizes the elliptical motion of the blade specimen, achieving a more realistic simulation effect, ensuring the accuracy of the prediction results. Moreover, only when the transverse sliding table or the longitudinal sliding table moves away from the blade specimen, the power required by the third push cylinder increases. Since the approaching and separating situations of the transverse sliding table and the blade specimen and the longitudinal sliding table and the blade specimen are opposite, it will not cause a large load on the third push cylinder. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0019] Figure 1 is a three-dimensional view of a wind turbine blade strength prediction device of the present invention Figure 1 ; Figure 2 is a front view of a wind turbine blade strength prediction device of the present invention; Figure 3 is a three-dimensional view of a wind turbine blade strength prediction device of the present invention Figure 2 ; Figure 4 is a three-dimensional view of a wind turbine blade strength prediction device of the present invention Figure 3 ; Figure 5 is a three-dimensional view of a wind turbine blade strength prediction device of the present invention Figure 4 ; Figure 6 is a three-dimensional view of the mobile blade tooling of the present invention Figure 1 ; Figure 7 is a three-dimensional view of the mobile blade tooling of the present invention Figure 2 ; Figure 8 is Figure 6 an enlarged view of part A in Figure 9 is Figure 7 an enlarged view of part B in Figure 10 is a three-dimensional view of the floating support assembly of the present invention.

[0020] The reference numerals in the drawings respectively represent: 1. Blade specimen; 2. Specimen support mechanism; 3. Movable blade tooling; 31. Support frame; 311. Cross bar; 312. Connecting plate; 32. Spacing adjustment assembly; 321. First support plate; 322. Adjusting motor; 323. Rotating rod; 324. Thread; 325. Screw sleeve; 33. Lateral support assembly; 331. Connecting sleeve; 332. Baffle; 34. Adaptive support assembly; 341. Second support plate; 342. Scissor bracket; 3421. Connecting rod; 3422. Pin shaft; 343. Servo push rod; 344. First push cylinder; 345. Arc support plate; 346. Pressure sensor; 347. Second push cylinder; 348. Support roller; 35. Moving assembly; 351. Moving motor; 352. Fixed moving wheel; 4. Composite swing control mechanism; 41. Bracket; 42. Horizontal slide bar; 43. Horizontal slide table; 44. Horizontal connecting rod; 45. Vertical slide bar; 46. Vertical slide table; 47. Vertical connecting rod; 48. Linking rod; 49. Third push cylinder. Detailed implementation mode

[0021] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0022] The "left", "right", "front", "rear", "upper" and "lower" mentioned in the following description are oriented in the perspective direction of the front view.

[0023] Embodiment 1: In some embodiments, please refer to the Figure 1 , Figure 2 , Figure 5 and Figure 6 , a wind turbine blade strength prediction device, including a specimen support mechanism 2 for fixedly connecting with the blade root of the blade specimen 1 and a movable blade tooling 3 fixed outside the blade specimen 1; The specimen support mechanism 2 can adopt a wall structure formed by welding profiles or pouring concrete, and a fixed method of connecting with the blade root bolt of the blade specimen 1 by a flange; The mobile blade tooling 3 includes a support frame 31, a spacing adjustment component 32, a lateral support component 33, and an adaptive support component 34. Two support frames 31 are symmetrically arranged on the upper and lower sides of the blade specimen 1. A moving component 35 is arranged in the middle of the support frame 31, and the moving component 35 is used to drive the support frame 31 to move along the length direction of the blade specimen 1; Adaptive support components 34 are symmetrically arranged on both sides of the support frame 31, and the adaptive support components 34 are used to fit with the upper and lower outer walls of the blade specimen 1 so that the support frame 31 remains horizontal on the blade specimen 1; A spacing adjustment component 32 is arranged between the two ends of the two support frames 31, and the spacing adjustment component 32 is used to adjust the spacing between the upper and lower support frames 31. A lateral support component 33 is also arranged at the moving end of each support frame 31, and the lateral support component 33 is used to limit the left and right outer walls of the blade specimen 1; A compound swing control mechanism 4 is arranged on the lower side of the mobile blade tooling 3. The output end of the compound swing control mechanism 4 is connected to the support frame 31. The compound swing control mechanism 4 realizes dynamic force application to the blade specimen 1 in the flapping direction and the pitching direction through a single power source. The compound swing control mechanism 4 is fastened to the ground or the support platform; In the present invention, the mobile blade tooling 3 is installed at the mid-span of the blade specimen 1. The spacing between the upper and lower support frames 31 is adjusted through the spacing adjustment component 32, so that the moving components 35 on the two support frames 31 are respectively in contact with the upper and lower side walls of the blade specimen 1, and the adaptive support component 34 is controlled to be in profile contact with the upper and lower outer walls of the blade specimen 1 so that the support frame 31 remains horizontal. With the cooperation of the lateral support component 33, the entire mobile blade tooling 3 is tightly connected to the outer wall of the blade specimen 1. Subsequently, the support frame 31 is driven to move through the moving component 35, and the position of the mobile blade tooling 3 is adjusted to the set point of the blade specimen 1. The blade specimen 1 is clamped through the adaptive support component 34 so that the support frame 31 is fastened to the blade specimen 1. Then, the output end of the compound swing control mechanism 4 is connected to the blade specimen 1, and dynamic force application to the blade specimen 1 is realized through the compound swing control mechanism 4. When the number of cycles of dynamic force application reaches the set value, the strength of each point of the blade specimen 1 is detected, and then the position of the support frame 31 on the blade specimen 1 is adjusted for dynamic force application operation. Repeat several times to realize multi-point force application detection of the blade specimen 1. Through comprehensive analysis of the data of each point, potential defects in each area, such as delamination, microcracks, etc., are actively excited, avoiding the blind area of single loading point testing, so as to achieve a more real and practical simulation effect and ensure the accuracy of the prediction result.

[0024] Please refer to Figures 5 - 10, the support frame 31 is composed of two parallel cross bars 311 and a connecting plate 312 fixedly installed between the middles of the cross bars 311. Linear guide rails are fixedly installed on the cross bars 311. The moving assembly 35 includes a moving motor 351 and fixed moving wheels 352. At one end of the connecting plate 312 close to the blade specimen 1, two fixed moving wheels 352 that are in rolling connection with the outer wall of the blade specimen 1 are rotatably installed. The fixed moving wheels 352 are distributed along the length direction of the blade specimen 1. At the other end of the connecting plate 312, a moving motor 351 is fixedly installed. The output end of the moving motor 351 is in transmission connection with any one of the fixed moving wheels 352 through a transmission assembly. The transmission assembly can adopt a belt and pulley transmission structure; The adaptive support assembly 34 includes a second support plate 341, a scissor support 342, a servo push rod 343, and a floating support assembly. A plurality of second support plates 341 are provided and evenly distributed at equal intervals along the length direction of the blade specimen 1. The second support plates 341 are in limit sliding connection with the linear guide rails on the cross bars 311 through sliders. A floating support assembly that is in imitation fit with the side wall of the blade specimen 1 is provided on each second support plate 341; The servo push rod 343 is fixedly connected to the end of the cross bar 311, and the output end of the servo push rod 343 is fixedly connected to the second support plate 341; The scissor support 342 is formed by connecting a plurality of scissor members end to end. The scissor member includes two connecting rods 3421 and a pin shaft 3422. The pin shaft 3422 is hinged to the middle of the two connecting rods 3421. A plurality of pin shafts 3422 are respectively fixedly connected to the second support plates 341, and the pin shaft 3422 closest to the connecting plate 312 is fixedly connected to the connecting plate 312, so that the second support plate 341 can expand or contract along the length direction of the cross bar 311 starting from the connecting plate 312; The servo push rod 343 is fixedly connected to the end of the blade specimen 1, and the output end of the servo push rod 343 is fixedly connected to the outermost second support plate 341; The floating support assembly is composed of multiple groups of moving floating support structures and fixed floating support structures arranged alternately on the second support plate 341. The moving floating support structure is used to fit with the outer wall of the blade specimen 1 when the support frame 31 moves on the blade specimen 1 to keep the support frame 31 balanced. The fixed floating support structure is used to fit with the outer wall of the blade specimen 1 when the support frame 31 needs to be fixed outside the blade specimen 1 to keep the support frame 31 and the blade specimen 1 fastened; The fixed floating support structure includes a first push cylinder 344, an arc-shaped support plate 345 and a pressure sensor 346. The first push cylinder 344 is fixedly connected to the second support plate 341. The output end of the first push cylinder 344 is hinged to the arc-shaped support plate 345. The arc-shaped support plate 345 is restricted by the rotation of the hinge seat so that the rotation range of the arc-shaped support plate 345 is 45 degrees to 135 degrees. The arc-shaped support plate 345 is provided with an anti-skid rubber layer for increasing friction. Pressure sensors 346 are provided at both ends of the arc-shaped support plate 345. The mobile floating support structure includes a second push cylinder 347, a support roller 348 and a pressure sensor 346. The second push cylinder 347 is fixedly connected to the second support plate 341. The output end of the second push cylinder 347 is equipped with a pressure sensor 346. The lower end of the pressure sensor 346 is equipped with a support roller 348. The support roller 348 is a steel ball roller. The spacing adjustment component 32 includes a first support plate 321, an adjustment motor 322 and a rotating rod 323. The first support plate 321 is slidably connected to the linear guide on the cross bar 311 through a slider, and the first support plate 321 is fixedly connected to the outermost second support plate 341, so that the first support plate 321 and the second support plate 341 move synchronously; the two rotating rods 323 are rotatably connected to the first support plate 321 on the upper support frame 31 through bearings and are symmetrically distributed front and back, and the two rotating rods 323 are connected by a transmission assembly to achieve synchronous rotation, and the transmission assembly can adopt a synchronous belt and synchronous pulley transmission structure; the lower end of the rotating rod 323 is provided with a thread 324, and a screw sleeve 325 matching the thread 324 is fixedly installed on the first support plate 321 of the lower support frame 31; the adjusting motor 322 is fixedly connected to the first support plate 321, and the output end of the adjusting motor 322 is fixedly connected to any rotating rod 323; The lateral support assembly 33 includes a connecting sleeve 331 and a baffle 332. The connecting sleeve 331 is rotatably mounted on the first support plate 321 through a bearing. The baffle 332 is fixedly mounted between the connecting sleeves 331. The baffle 332 is used to abut against the side of the blade specimen 1. In the present invention, by adjusting the motor 322 to drive the rotating rod 323 to rotate, the two support frames 31 move towards or away from each other under the cooperation of the thread 324 and the screw sleeve 325, so as to adjust the distance between the two support frames 31 and adapt to different thickness parts of the blade specimen 1; by the servo push rod 343 to push the first support plate 321 and the second support plate 341 to move synchronously along the length direction of the blade specimen 1, so that the rotating rods 323 of the lateral support assemblies 33 on both sides of the support frame 31 approach or move away from each other until the baffles 332 on both sides abut against both sides of the blade specimen 1 to adapt to different width parts of the blade specimen 1. At the same time, under the action of the scissor bracket 342, all the second support plates 341 move equidistantly, so that the floating support assemblies are always evenly distributed along the width direction of the blade specimen 1 to ensure the uniformity of the support effect; When it is necessary to change the force application point on the blade specimen 1, the second push cylinder 347 drives the support roller 348 to move vertically until the reading of the pressure sensor 346 at the end of the second push cylinder 347 reaches the set value, and the output end of the second push cylinder 347 stops moving, so that each support roller 348 is in contact with the outer wall of the blade specimen 1 and the force is balanced. The fixed moving wheel 352 is rotated by the moving motor 351 to drive the support frame 31 to move along the length direction of the blade specimen 1; After the support frame 31 moves to the force application point of the blade specimen 1, the first push cylinder 344 drives the arc-shaped support plate 345 to move vertically. After the arc-shaped support plate 345 contacts the outer wall of the blade specimen 1, it will automatically rotate to adjust its angle so that the contact area between the arc-shaped support plate 345 and the outer wall of the blade specimen 1 is the largest. When the readings of the pressure sensors 346 at both ends of the arc-shaped support plate 345 reach the set value, the output end of the first push cylinder 344 stops moving, so that each arc-shaped support plate 345 is evenly stressed, thus realizing the fastening effect on the blade specimen 1.

[0025] The compound swing control mechanism 4 includes a bracket 41, a longitudinal swing assembly, a transverse swing assembly, a linkage rod 48 and a third push cylinder 49. The longitudinal swing assembly is arranged on the lower side of the blade specimen 1. The bracket 41 is arranged on the left or right side of the blade specimen 1. The top of the bracket 41 is provided with a transverse swing assembly. The two ends of the linkage rod 48 are respectively hinged to the mobile ends of the longitudinal swing assembly and the transverse swing assembly; the third push cylinder 49 is fixedly installed at the upper end of the bracket 41, and the output end of the third push cylinder 49 is fixedly connected to the mobile end of the transverse swing assembly; the mobile ends of the longitudinal swing assembly and the transverse swing assembly are respectively connected to the bottom and the side of the support frame 31, and are respectively used to control the swing of the blade specimen 1 in the flapping direction and the pitching direction; Please refer to Figures 3 - 5, the lateral swing assembly includes a lateral slide bar 42, a lateral slide table 43 and a lateral connecting rod 44. The lateral slide bar 42 is fixedly connected to the top of the bracket 41. The lateral slide table 43 is slidably connected to the lateral slide bar 42 with a limit. The two ends of the lateral connecting rod 44 are respectively hinged to the side surface of the support frame 31 and the lateral slide table 43. The output end of the third push cylinder 49 is fixedly connected to the lateral slide table 43; The longitudinal swing assembly includes a longitudinal slide bar 45, a longitudinal slide table 46 and a longitudinal connecting rod 47. The lower end of the longitudinal slide bar 45 is fixed to the ground or the support platform. The longitudinal slide table 46 is slidably connected to the longitudinal slide bar 45 with a limit. The two ends of the longitudinal connecting rod 47 are respectively hinged to the lower end of the support frame 31 and the longitudinal slide table 46; The two ends of the linkage rod 48 are respectively hinged to the lateral slide table 43 and the longitudinal slide table 46. The linkage rod 48 adopts a telescopic rod structure. By changing the length of the linkage rod 48, the swing trajectory of the blade specimen 1 can be changed, so as to realize the life detection of the blade specimen 1 under different torsion conditions; In the present invention, under the action of the linkage rod 48, when the lateral slide table 43 approaches the blade specimen 1, the longitudinal slide table 46 synchronously moves away from the blade specimen 1, and when the lateral slide table 43 moves away from the blade specimen 1, the longitudinal slide table 46 synchronously approaches the blade specimen 1. Thus, under the drive of a single power source of the third push cylinder 49, the swing of the blade specimen 1 in the flapping direction and the waving direction can be controlled. The combination of the two realizes the elliptical motion of the blade specimen 1, achieving a more realistic simulation effect and ensuring the accuracy of the prediction results. Moreover, only when the lateral slide table 43 or the longitudinal slide table 46 moves away from the blade specimen 1, the power required by the third push cylinder 49 increases. The approach and separation of the lateral slide table 43 from the blade specimen 1 and the longitudinal slide table 46 from the blade specimen 1 are opposite, and will not cause a large load on the third push cylinder 49.

[0026] Embodiment 2: In some embodiments, as Figures 1 - 10 shown, as a preferred embodiment of the present invention, a prediction method for a wind turbine blade strength prediction device includes the following steps: Step 1: Install sensors such as strain gauges, displacement gauges, and accelerometers on the surface and inside of the blade specimen 1 at a set spacing along the length of the blade specimen 1, for example, at an interval of one meter; Step 2: Install the mobile blade tooling 3 at the mid-span of the blade specimen 1. Adjust the spacing between the upper and lower support frames 31 through the spacing adjustment assembly 32, so that the moving components 35 on the two support frames 31 always fit the upper and lower side walls of the blade specimen 1 to adapt to different thickness parts of the blade specimen 1; Step 3: Push the first support plate 321 and the second support plate 341 to move synchronously along the length direction of the blade specimen 1 through the servo push rod 343, so that the baffles 332 on both sides always abut against both sides of the blade specimen 1 to adapt to different width parts of the blade specimen 1; Step 4: Drive the supporting roller 348 to move vertically through the second push cylinder 347. When the reading of the pressure sensor 346 at the end of the second push cylinder 347 reaches the set value, the output end of the second push cylinder 347 stops moving, so that each supporting roller 348 is in contact with the outer wall of the blade specimen 1 and the force is balanced. Then, control the rotation of the fixed moving wheel 352 through the moving motor 351 to drive the supporting frame 31 to move along the length direction of the blade specimen 1 to the force application point; Step 5: After the supporting frame 31 moves to the force application point of the blade specimen 1, drive the arc-shaped supporting plate 345 to move vertically through the first push cylinder 344. After the arc-shaped supporting plate 345 contacts the outer wall of the blade specimen 1, it will automatically rotate to adjust its angle to make the contact area between the arc-shaped supporting plate 345 and the outer wall of the blade specimen 1 the largest. When the readings of the pressure sensors 346 at both ends of the arc-shaped supporting plate 345 reach the set value, the output end of the first push cylinder 344 stops moving, so that each arc-shaped supporting plate 345 is evenly stressed, and then the supporting frame 31 is fastened to the blade specimen 1; Step 6: The third push cylinder 49 drives the transverse sliding table 43 to reciprocate horizontally. The transverse sliding table 43 drives the longitudinal sliding table 46 to reciprocate synchronously vertically through the linkage rod 48. Moreover, the approaching and separating situations of the transverse sliding table 43 and the blade specimen 1 and the longitudinal sliding table 46 and the blade specimen 1 are opposite. The two are combined to realize the elliptical motion of the blade specimen 1. After the test is completed, the first push cylinder 344 drives the arc-shaped supporting plate 345 to reset; Step 7: Check whether the readings of each sensor meet the set value; Step 8: Repeat Step 4 to Step 7 until fatigue tests are carried out on multiple points at the blade midpoint and blade tip of the blade specimen 1, and comprehensively judge the strength of the blade specimen 1 through the readings of the sensors.

[0027] 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 foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements will not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A wind turbine blade strength prediction device, comprising a specimen support mechanism (2) for fixedly connecting with the blade root of a blade specimen (1) and a mobile blade tooling (3) fixed on the outer side of the blade specimen (1), characterized in that: The mobile blade tooling (3) includes a support frame (31), a spacing adjustment component (32), a lateral support component (33) and an adaptive support component (34). Two support frames (31) are symmetrically arranged on the upper and lower sides of the blade specimen (1). A moving component (35) is arranged in the middle of the support frame (31). The moving component (35) is used to drive the support frame (31) to move along the length direction of the blade specimen (1). Adaptive support components (34) are symmetrically arranged on both sides of the support frame (31). The adaptive support component (34) is used to fit with the upper and lower outer walls of the blade specimen (1) so that the support frame (31) remains horizontal on the blade specimen (1). Spacing adjustment components (32) are arranged between the two ends of the two support frames (31). The spacing adjustment component (32) is used to adjust the spacing between the upper and lower support frames (31). A lateral support component (33) is also arranged at the mobile end of each support frame (31). The lateral support component (33) is used to limit the left and right outer walls of the blade specimen (1). A compound swing control mechanism (4) is arranged on the lower side of the mobile blade tooling (3). The output end of the compound swing control mechanism (4) is connected with the support frame (31). The compound swing control mechanism (4) realizes dynamic force application to the blade specimen (1) in the flapping direction and the pitching direction through a single power source. The compound swing control mechanism (4) is fastened to the ground or a support platform.

2. The wind turbine blade strength prediction device according to claim 1, characterized in that, The support frame (31) is composed of two parallel cross bars (311) and a connecting plate (312) fixedly installed between the middle parts of the cross bars (311). The moving component (35) includes a moving motor (351) and fixed moving wheels (352). Two fixed moving wheels (352) that are in rolling connection with the outer wall of the blade specimen (1) are rotatably installed at one end of the connecting plate (312) close to the blade specimen (1). The fixed moving wheels (352) are distributed along the length direction of the blade specimen (1). A moving motor (351) is fixedly installed at the other end of the connecting plate (312). The output end of the moving motor (351) is in transmission connection with any one of the fixed moving wheels (352) through a transmission component.

3. The wind turbine blade strength prediction device according to claim 2, characterized in that, The adaptive support assembly (34) includes a second support plate (341), a scissor bracket (342), a servo push rod (343), and a floating support assembly. A plurality of second support plates (341) are provided and evenly distributed at equal intervals along the length direction of the blade specimen (1). The second support plates (341) are connected to the cross bar (311) in a limit sliding manner. A floating support assembly that is shaped to fit the side wall of the blade specimen (1) is provided on each second support plate (341). The servo push rod (343) is fixedly connected to the end of the cross bar (311), and the output end of the servo push rod (343) is fixedly connected to the second support plate (341). A scissor bracket (342) is provided on the second support plate (341), so that the second support plate (341) can expand or contract along the length direction of the cross bar (311) starting from the connecting plate (312).

4. The wind power blade strength prediction device according to claim 3, characterized in that The floating support assembly is composed of multiple groups of moving floating support structures and fixed floating support structures that are staggered on the second support plate (341). The moving floating support structures are used to fit the outer wall of the blade specimen (1) when the support frame (31) moves on the blade specimen (1) to keep the support frame (31) balanced. The fixed floating support structures are used to fit the outer wall of the blade specimen (1) when the support frame (31) needs to be fixed outside the blade specimen (1) to keep the support frame (31) and the blade specimen (1) fastened.

5. The wind power blade strength prediction device according to claim 4, characterized in that, The fixed floating support structure includes a first push cylinder (344), an arc-shaped support plate (345), and a pressure sensor (346). The first push cylinder (344) is fixedly connected to the second support plate (341), and the output end of the first push cylinder (344) is hinged to the arc-shaped support plate (345). And the arc-shaped support plate (345) is restricted by the hinge seat to rotate within a range of 45 degrees to 135 degrees. An anti-slip rubber layer for increasing friction is provided on the arc-shaped support plate (345). Pressure sensors (346) are provided at both ends of the arc-shaped support plate (345).

6. The wind power blade strength prediction device according to claim 5, characterized in that The moving floating support structure includes a second push cylinder (347), a support roller (348), and a pressure sensor (346). The second push cylinder (347) is fixedly connected to the second support plate (341), a pressure sensor (346) is installed at the output end of the second push cylinder (347), and a support roller (348) is installed at the lower end of the pressure sensor (346).

7. The wind turbine blade strength prediction device according to claim 6, characterized in that, The spacing adjustment assembly (32) comprises a first support plate (321), an adjustment motor (322) and a rotating rod (323); the first support plate (321) is slidably connected to the cross bar (311) in a limited position, and the first support plate (321) is fixedly connected to the outermost second support plate (341); the two rotating rods (323) are rotatably connected to the first support plate (321) on the upper support frame (31) through bearings and are symmetrically distributed front to back; the two rotating rods (323) are transmission-connected through a transmission assembly to achieve synchronous rotation; the lower end of the rotating rod (323) is provided with a thread (324); a screw sleeve (325) matching the thread (324) is fixedly mounted on the first support plate (321) of the lower support frame (31); the adjustment motor (322) is fixedly connected to the first support plate (321), and the output end of the adjustment motor (322) is fixedly connected to any rotating rod (323).

8. The wind turbine blade strength prediction device according to claim 7, characterized in that, The lateral support assembly (33) comprises a connecting sleeve (331) and a baffle (332); the connecting sleeve (331) is rotatably mounted on each of the first support plates (321) via a bearing; the baffle (332) is fixedly mounted between the connecting sleeves (331); the baffle (332) is used to abut against the side surface of the blade specimen (1).

9. The wind power blade strength prediction device according to claim 8, wherein, The composite swing amplitude control mechanism (4) comprises a bracket (41), a longitudinal swing component, a transverse swing component, a linkage rod (48) and a third push cylinder (49); the longitudinal swing component is arranged on the lower side of the blade specimen (1); the bracket (41) is arranged on the left or right side of the blade specimen (1); the top of the bracket (41) is provided with a transverse swing component; the two ends of the linkage rod (48) are respectively hinged to the movable ends of the longitudinal swing component and the transverse swing component; the third push cylinder (49) is fixedly mounted on the upper end of the bracket (41); the output end of the third push cylinder (49) is fixedly connected to the movable end of the transverse swing component; the movable ends of the longitudinal swing component and the transverse swing component are respectively connected to the bottom and the side of the support frame (31), and are respectively used to control the swing of the blade specimen (1) in the swing direction and the swinging direction.

10. A prediction method, using the wind turbine blade strength prediction device according to claim 9, characterized in that, The following steps are involved: Step 1: Installing strain gauges, displacement meters and accelerometers on the surface and inside of the blade specimen (1) along the length of the blade specimen (1) at set intervals; Step 2: Install the movable blade fixture (3) at the middle of the blade specimen (1), and adjust the distance between the upper and lower support frames (31) by means of the distance adjustment component (32), so that the movable components (35) on the two support frames (31) always fit the upper and lower side walls of the blade specimen (1) to adapt to the parts of the blade specimen (1) with different thicknesses; Step 3: using the servo push rod (343) to push the first support plate (321) and the second support plate (341) to move synchronously along the length direction of the blade specimen (1), so that the baffles (332) on both sides always abut against both sides of the blade specimen (1) to adapt to parts of the blade specimen (1) with different widths; Step 4: Drive the support rollers (348) to move vertically through the second push cylinder (347). When the reading of the pressure sensor (346) at the end of the second push cylinder (347) reaches the set value, the output end of the second push cylinder (347) stops moving, so that each support roller (348) is in contact with the outer wall of the blade specimen (1) and the force is balanced. Then, control the rotation of the fixed moving wheel (352) through the moving motor (351) to drive the support frame (31) to move along the length direction of the blade specimen (1) to the force application point; Step 5: After the support frame (31) moves to the force application point of the blade specimen (1), drive the arc-shaped support plate (345) to move vertically through the first push cylinder (344). After the arc-shaped support plate (345) contacts the outer wall of the blade specimen (1), it will automatically rotate to adjust its angle to make the contact area between the arc-shaped support plate (345) and the outer wall of the blade specimen (1) the largest. When the readings of the pressure sensors (346) at both ends of the arc-shaped support plate (345) reach the set value, the output end of the first push cylinder (344) stops moving, so that each arc-shaped support plate (345) is evenly stressed, and then the support frame (31) is fastened to the blade specimen (1); Step 6: The third push cylinder (49) drives the mobile end of the lateral swing assembly to reciprocate horizontally. The mobile end of the lateral swing assembly drives the mobile end of the longitudinal swing assembly to reciprocate synchronously vertically through the linkage rod (48). Moreover, the approach and separation between the mobile end of the lateral swing assembly and the blade specimen (1) and between the mobile end of the longitudinal swing assembly and the blade specimen (1) are opposite. The two are combined to realize the elliptical motion of the blade specimen (1). After the test is completed, the first push cylinder (344) drives the arc-shaped support plate (345) to reset; Step 7: Check whether the readings of the strain gauges, displacement gauges, and accelerometers meet the set values; Step 8: Repeat steps 4 to 7 until fatigue tests are carried out on multiple points at the blade midpoint and blade tip of the blade specimen (1), and comprehensively judge the strength of the blade specimen (1) based on the readings of the sensors.

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