CN118275020A - Torsion test system and torsion test method for fan blade - Google Patents

Abstract

The present disclosure provides a torsion test system and torsion test method for wind turbine blades. The torsion test system includes: a test bench for fixing the root of the wind turbine blade; a clamping portion for clamping the tip of the wind turbine blade; a load-applying portion connected to at least one side of the clamping portion, for applying a load to the wind turbine blade through the clamping portion to cause the wind turbine blade to twist; a detection component for obtaining torsion deformation data at multiple positions of the wind turbine blade; a controller for calculating the torsion torque applied by the load-applying portion to the wind turbine blade based on the loaded load, and determining the torsion stiffness of the wind turbine blade based on the torsion torque and the torsion deformation data. By calculating the torsion stiffness of the wind turbine blade, it is possible to avoid problems with aeroelasticity and vibration of the wind turbine blade during operation, and it is beneficial to the design and development of large-sized wind turbine blades.

Description

Torsion test system and torsion test method for wind turbine blades

Technical Field

The present disclosure relates to the technical field of wind turbine testing, and more specifically, to a torsion testing system and a torsion testing method for wind turbine blades.

Background technique

As the size of wind turbine blades continues to increase, the flexibility of wind turbine blades becomes more and more obvious. Torsion, as an inherent property of wind turbine blades, has an increasingly greater impact on the overall performance of blades. For example, torsion can cause aeroelastic problems and blade operation vibration problems.

However, when measuring the strain state in the torsion test, the amount of data obtained is limited, making it difficult to fully test the blade surface data. In addition, the torsion deformation is much smaller than the bending deformation, and the existing methods for measuring torsion deformation are not accurate, resulting in poor convergence of multiple measurement results.

The current torsion test simulation and related data support are very weak. For the current status of theoretical calculations and related software calculations, it is difficult to obtain reliable and comprehensive torsion test data as a standard for simulation data correction, and therefore it is difficult to obtain accurate torsional stiffness of wind turbine blades.

Summary of the invention

Therefore, an object of the present disclosure is to provide a torsion testing system and a torsion testing method for a wind blade, which are capable of obtaining accurate torsional stiffness of the wind blade.

The present disclosure also aims to provide a torsion testing system and a torsion testing method for wind turbine blades, which can improve the rationality and reliability of blade design and development.

According to one aspect of the present disclosure, a torsion testing system for a wind blade is provided, the torsion testing system comprising: a test bench for fixing the root portion of the wind blade; a clamping portion for clamping the tip portion of the wind blade; a load applying portion connected to at least one side of the clamping portion, for applying a load to the wind blade through the clamping portion so as to twist the wind blade; a detection component for obtaining torsional deformation data at multiple positions of the wind blade; and a controller for calculating the torsional torque applied by the load applying portion to the wind blade based on the loaded load, and determining the torsional stiffness of the wind blade according to the torsional torque and the torsional deformation data.

Preferably, the torsion testing system may further include an inclinometer, which is mounted on the clamping part and is used to measure the angle change of the clamping part during the loading process of the load. The controller may calculate the torsional torque applied by the load loading part to the wind turbine blade based on the loaded load and the angle measured by the inclinometer.

Preferably, the detection assembly may include a plurality of detection lines arranged on the surface of the wind blade, the plurality of detection lines extending along the chord direction of the wind blade and spaced apart along the span direction of the wind blade, and the plurality of detection lines are used to detect the degree of torsional deformation of multiple cross sections of the wind blade.

Preferably, the detection component may also include a thermal imaging device, the detection line may be a resistance wire connected to a power source, capable of generating heat during the loading process of the load, and the thermal imaging device may capture a thermal image of the resistance wire during the loading process of the load.

Preferably, the detection component may further include a piezoelectric signal capturer, the detection line may be formed of a piezoelectric material, and the piezoelectric signal capturer can acquire a piezoelectric signal from the detection line during the loading process of the load.

Preferably, the detection component may include a camera, and a plurality of spots may be arranged on the surface of the wind blade, the camera can capture a picture of the wind blade during the loading process of the load, and the controller can determine the torsional deformation data of the wind blade based on the captured picture.

Preferably, the clamping portion may include a clamp body and a loading arm extending outward from the clamp body, and the inclinometer is disposed on the loading arm.

Preferably, the clamping portion may include a first clamp and a second clamp that are arranged opposite to each other, and the first clamp and the second clamp clamp the fan blade at the pressure side and the suction side of the fan blade respectively.

Preferably, the clamping portion may further include a connecting rod and a supporting rod, both ends of the connecting rod are respectively connected to the first clamp and the second clamp, and one end of the supporting rod is connected to the connecting rod and the other end of the supporting rod is fixed.

Preferably, a conformal block matching the shape of the pressure side and the suction side of the fan blade may be disposed inside each of the first clamp and the second clamp.

According to another aspect of the present disclosure, a torsion test method for a wind blade is provided, the torsion test method comprising the following steps: fixing the root portion of the wind blade to a test bench, and clamping the tip portion of the wind blade with a clamping portion to keep the wind blade in a horizontal state; arranging detection components at multiple positions on the surface of the wind blade, and connecting the detection components to a controller; connecting a load loading portion to at least one side of the clamping portion, and applying a load to the wind blade through the clamping portion to cause the wind blade to twist; the controller obtains torsional deformation data of the wind blade from the detection component, calculates the torsional torque applied to the wind blade by the load loading portion based on the loaded load, and determines the torsional stiffness of the wind blade according to the torsional torque and the torsional deformation data.

Preferably, the step of arranging the detection component may include: installing an inclinometer on the clamping part, the inclinometer being used to measure the angle change of the clamping part during the loading process of the load, wherein the step of calculating the torsional moment may include: calculating the torsional moment based on the loaded load and the angle measured by the inclinometer.

Preferably, the step of arranging the detection component may include: setting a plurality of detection lines on the surface of the wind blade, the plurality of detection lines extending along the chord direction of the wind blade and spaced apart along the span direction of the wind blade, the plurality of detection lines being used to detect the degree of torsional deformation of multiple cross sections of the wind blade.

Alternatively, a plurality of spots are arranged on the wind blade, the detection component comprises a camera, the camera is capable of capturing a picture of the wind blade during the loading process of the load, and the controller is capable of determining the torsional deformation data of the wind blade based on the captured picture.

By adopting the above-mentioned torsion test system and torsion test method, the torsional stiffness of the wind turbine blades can be accurately calculated, thereby avoiding the aeroelasticity problem and blade operation vibration problem caused by insufficient stiffness of the wind turbine blades, and facilitating the design and development of large-sized wind turbine blades.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the present disclosure will be more clearly understood when the following detailed description is given in conjunction with the accompanying drawings, in which:

FIG1 is a schematic plan view showing a torsion test system for a wind turbine blade according to an embodiment of the present disclosure;

FIG2 is a schematic plan view showing a torsion test system for a wind turbine blade according to another embodiment of the present disclosure;

3 is a cross-sectional view showing a torsion test system for a wind turbine blade according to a first embodiment of the present disclosure;

4 is a cross-sectional view showing a torsion test system for a wind turbine blade according to a second embodiment of the present disclosure;

5 is a cross-sectional view showing a torsion test system for a wind turbine blade according to a third embodiment of the present disclosure;

FIG. 6 is a cross-sectional view showing a torsion testing system for a wind turbine blade according to a fourth embodiment of the present disclosure.

Detailed ways

Embodiments according to the present disclosure will be described in detail with reference to the accompanying drawings, examples of which are shown in the accompanying drawings, wherein like reference numerals refer to like components throughout.

Fig. 1 and Fig. 2 show plan schematic diagrams of a torsion test system for a wind turbine blade according to two embodiments of the present disclosure, mainly showing detection lines and spots on the surface of the wind turbine blade. Fig. 3 to Fig. 6 show cross-sectional views of a torsion test system according to the first to fourth embodiments of the present disclosure, mainly showing the differences in the clamping portion, the loading method and the torsion test method. The specific structure of the torsion test system for a wind turbine blade and the torsion test method according to the present disclosure will be described below with reference to Fig. 1 to Fig. 6.

As shown in Figures 1 to 6, the torsion test system includes: a test bench 10, used to fix the root of the fan blade 20; a clamping portion 30, used to clamp the tip of the fan blade 20; a load applying portion 40, connected to at least one side of the clamping portion 30, and used to apply a load to the fan blade 20 through the clamping portion 30 to cause the fan blade 20 to twist; a detection component, used to obtain torsional deformation data at multiple positions of the fan blade 20; a controller (not shown), which calculates the torsional torque applied by the load loading portion 40 to the fan blade 20 based on the loaded load, and determines the torsional stiffness of the fan blade 20 according to the torsional torque and the torsional deformation data.

In the present disclosure, the load applied by the load-applying part 40 to the clamping part 30 can be transmitted to the fan blade 20, causing the fan blade 20 to twist. At the same time, the detection component can obtain the torsional deformation data of multiple positions of the fan blade 20, and the controller calculates the torsional stiffness of the fan blade 20 according to the torsional moment and torsional deformation data of the fan blade 20. By adopting the above-mentioned torsion test system, the torsional stiffness of the fan blade can be accurately calculated, so as to determine whether the comprehensive performance of the blade meets the design requirements of the fan blade, avoid the air elasticity problem and the blade operation vibration problem of the fan blade due to insufficient stiffness, and facilitate the design and development of large-sized fan blades.

In one embodiment of the present disclosure, as shown in FIG. 1 , the detection assembly may include a plurality of detection lines 61 disposed on the surface of the fan blade 20, the plurality of detection lines 61 extending along the chord direction of the fan blade 20 and spaced apart along the span direction of the fan blade 20, and the plurality of detection lines 61 are used to detect the torsional deformation degree of multiple sections of the fan blade 20. The controller determines the torsional deformation data (e.g., torsion angle and surface strain, etc.) of the fan blade 20 according to the torsional deformation of multiple sections detected by the detection lines 61. In the present disclosure, the setting interval of the detection lines 61 may be small, so that dense detection lines 61 are formed on the blade surface, so that the torsional deformation of more sections of the fan blade 20 can be detected. The torsional deformation data may be calculated based on the deformation difference between two sections (e.g., a section before deformation and a section after deformation, or two adjacent sections) (which will be described in detail later). The blade characteristics are different in each section, and the closer the adjacent sections are to each other, the more they can represent the section characteristics, so that the obtained blade characteristics are more accurate and closer to the actual situation. The accuracy of the final evaluation result may be improved by increasing the density of the section arrangement in the span direction.

By using multiple detection lines 61 to detect the degree of torsional deformation of multiple cross-sections of the fan blade 20, the blade surface data can be tested more comprehensively (more comprehensively and objectively reflecting the response of the fan blade 20 under the action of load) and the amount of torsional deformation data obtained can be increased, thereby improving the accuracy of torsional test simulation and torsional stiffness calculation, and improving the rationality and reliability of blade design and development. Compared with the point distribution detection method, since the detection line 61 extends around the chord direction of the fan blade 20, the measurement continuity of the detection line 61 is better, and the torsional deformation of the entire cross-section of the fan blade 20 can be measured. Therefore, the measurement accuracy of the detection line 61 is higher, and the convergence of multiple measurement results is better.

Optionally, the detection line 61 can be a resistance wire and connected to a power source. During the loading process of the load, the resistance wire generates heat due to the power supply. The detection assembly can also include a thermal imaging device (not shown), and the thermal imaging device can capture the thermal image of the resistance wire during the loading process of the load. The controller or computer can process the obtained thermal images of multiple cross sections, and obtain the torsional deformation data of the fan blade by analysis and comparison.

Optionally, the detection line 61 may be formed of a piezoelectric material. During the load loading process, a piezoelectric signal is generated on the detection line 61. The detection assembly may also include a piezoelectric signal capturer (not shown), which can obtain a piezoelectric signal from the detection line 61 during the load loading process. The controller or computer can process the obtained piezoelectric signals of multiple cross sections, and obtain the torsional deformation data of the wind turbine blade by analysis and comparison.

In another embodiment of the present disclosure, as shown in FIG. 2 , the detection component may include a camera (not shown), and a plurality of spots 62 may be provided on the surface of the wind blade 20. For example, the spots 62 are arranged by spraying or stickers, and the density of the spots 62 is relatively high. The camera can capture images of the wind blade 20 during the loading process of the load, and the controller can determine the torsional deformation data (e.g., torsion angle and surface strain, etc.) of the wind blade 20 based on the captured images. For example, based on the DIC (digital image correlation) measurement technology, the torsional deformation data of the wind blade 20 can be obtained by analyzing and comparing the captured images (which can be analyzed and compared based on the positions of the spots 62). For example, the image before deformation can be compared with the image after deformation, and the deformation difference between the two images can be obtained to calculate the torsional deformation data. Since multiple spots 62 are densely arranged on the surface of the wind blade 20, the above method can obtain torsional deformation data of multiple positions on the blade surface (the quantity of these numbers is much larger than the quantity collected by conventional methods), which makes the obtained torsional deformation data more accurate, so as to more comprehensively and objectively reflect the response of the wind blade under the action of load, thereby improving the accuracy of torsional test simulation and torsional stiffness calculation, and enhancing the rationality and reliability of blade design and development.

The clamping part 30 , the inclinometer 50 , and the load applying part 40 of the torsion testing system will be described below with reference to FIGS. 3 to 6 .

As shown in FIGS. 3 to 6 , the clamping portion 30 may include a first clamp 31 and a second clamp 32 that are arranged opposite to each other. The first clamp 31 and the second clamp 32 clamp the fan blade 20 at the pressure side and the suction side of the fan blade 20 , respectively.

The first clamp 31 and the second clamp 32 of the clamping part 30 can be referred to as a clamp body, and the clamping part 30 can also include a loading arm 33 extending outward from the clamp body. The torsion test system of the present disclosure can also include an inclinometer 50 (as shown in Figures 3 and 5), which is arranged on the loading arm 33. The inclinometer 50 is used to measure the angle change of the clamping part 30 during the loading process of the load, for example, to measure the angle change of the angle between the load loading direction of the load loading part 40 and the loading arm 33. The controller calculates the torsional moment applied by the load loading part 40 to the fan blade 20 based on the loaded load and the angle measured by the inclinometer 50. Since the torsion test system of the present disclosure takes into account the angle change of the clamping part 30 in the calculation process of the torsional moment, the torsional moment applied by the load loading part to the fan blade can be calculated more accurately, thereby improving the accuracy of the calculation of the torsional stiffness of the fan blade.

However, the present disclosure is not limited thereto, and the inclinometer may be installed at any position on the clamping portion as long as it can detect the angle change of the clamping portion. For example, the clamping portion may not include a loading arm, and as shown in FIG6 , the inclinometer may be installed at any position on the clamp body (e.g., the first clamp and/or the second clamp).

In addition, as shown in FIGS. 3 and 5 , an inclinometer 50 is installed on the loading arm 33 connected to each of the first clamp 31 and the second clamp 32. By measuring the angle change between the loading arm 33 connected to each of the first clamp 31 and the second clamp 32 and the load loading direction by two inclinometers 50, respectively, the angle change of the clamping portion 30 can be determined more accurately. However, the present disclosure is not limited thereto, and the inclinometer may be installed only on the loading arm connected to one of the first clamp and the second clamp, as long as the inclinometer can measure the angle change of the clamping portion.

In the torsion test system shown in FIGS. 3 to 5 , the load loading unit 40 applies a load to each of the first clamp 31 and the second clamp 32 through the loading arm 33, so that the wind turbine blade 20 is twisted. However, the present disclosure is not limited thereto, and the load loading unit may directly apply a load to each of the first clamp and the second clamp without using the loading arm. For example, in the case where the clamping unit does not include a loading arm, as shown in FIG. 6 , the load loading unit 40 may be directly connected to the clamp body.

In addition, in the embodiment shown in FIG. 6 , the load loading unit 40 can apply the load only to the second clamp 32 through the pulley 80, and no load loading unit applies the load to the first clamp 31. In contrast, in the embodiment shown in FIGS. 3 to 5 , the load loading unit 40 applies the load to both the first clamp 31 and the second clamp 32. That is, the load loading unit 40 can load the clamping unit 30 on both sides, or can load the clamping unit 30 on one side, and both loading conditions can cause the fan blade 20 to twist. As shown in FIGS. 3 to 6 , the load can be represented by a loading force F, and the direction of the arrow represents the loading direction of the load.

In addition, in the embodiments shown in FIGS. 3 to 6 , a load sensor 70 may be further provided between the load loading portion 40 and the clamping portion 30 (e.g., the loading arm 33 or the clamp body), and the load sensor 70 may detect the magnitude of the load applied by the load loading portion 40 to the clamping portion 30 (more specifically, to the fan blade 20). The controller may calculate the torsional moment applied by the load loading portion 40 to the fan blade 20 based on the load detected by the load sensor 70. The two load sensors 70 are respectively mounted on opposite sides of the clamping portion 30 (i.e., the first clamp 31 side and the second clamp 32 side). By measuring the loads on both sides of the clamping portion 30 by the two load sensors 70, the magnitude of the loads applied on both sides of the clamping portion 30 can be determined, and it is determined whether the loads on both sides are consistent. If the loads on both sides are inconsistent, the clamping portion 30 will cause the fan blade 20 to shake together, which affects the accuracy of the torsion test of the fan blade 20. In addition, when the loads on both sides of the clamping portion 30 are inconsistent, the load applied by the load applying portion 40 can be adjusted to make the loads on both sides of the clamping portion 30 consistent.

In addition, as shown in Figures 3 to 6, the clamping portion 30 may also include a connecting rod 34, and the two ends of the connecting rod 34 are respectively connected (for example, hinged) to the first clamp 31 and the second clamp 32. Specifically, the two connecting rods 34 connect the first clamp 31 and the second clamp 32 together on opposite sides of the first clamp 31 and the second clamp 32 (for example, the upper and lower sides shown in Figures 3 to 5, and the left and right sides shown in Figure 6). Therefore, during the torsion test, the first clamp 31 and the second clamp 32 can clamp the fan blade 20 and prevent the first clamp 31 and the second clamp 32 from separating from each other. The presence of the connecting rod 34 does not affect the angle change of the first clamp 31 and the second clamp 32 (that is, it does not affect the torsional deformation of the fan blade 20 caused by the clamping portion 30).

In addition, the clamping portion 30 may also include an anti-translation component for preventing the clamping portion 30 from translating (or moving) and not affecting the clamping portion 30 driving the fan blade 20 to twist. For example, as shown in FIG3 , the anti-translation component may be a support rod 35, one end of which is connected to the connecting rod 34, and the other end is fixed (for example, fixed to the ground). Since the root of the fan blade 20 is fixed by the test bench 10, the translation of the clamping portion 30 used to clamp the tip of the blade will generate a bending moment on the fan blade 20. The "translation" here refers to the translation of the fan blade 20 in a direction perpendicular to the span direction in addition to the twisting around the span direction. This translation generates a bending moment on the fan blade 20 and causes the fan blade 20 to bend and deform.

However, the present disclosure is not limited thereto, and the anti-translational motion component may also be any rigid component other than the support rod 35 , as long as it can limit the translation of the clamping portion 30 and thereby prevent the bending moment from being generated on the wind turbine blade 20 .

In the present disclosure, the torsion test system can determine the torsional stiffness of the wind blade 20 by a pure torsional moment test method and a bending-torsion coupling test method, and the difference between the two torsion test methods lies in whether the clamping part of the torsion test system undergoes translational motion. In addition, in the present disclosure, the torsion test system can not only calculate the torsional moment of the wind blade 20, but also analyze and process data related to the bending moment of the wind blade 20. Figures 3 and 4 show an example of determining the torsional stiffness of the wind blade 20 by a pure torsional moment test method, and Figures 5 and 6 show an example of determining the torsional stiffness of the wind blade 20 by a bending-torsion coupling test method. An embodiment of a torsion test system for performing the above two torsion test methods will be described in detail below.

In the torsion test system for wind blades according to the first embodiment of the present disclosure shown in FIG. 3 , the clamping portion 30 can only rotate under the constraint of the support rod 35, and does not move in translation (the wind blade 20 can only be deformed by torsion, not by bending). In other words, the support rod 35 constrains the translation of the wind blade 20 during the load loading process, thereby preventing the generation of bending moment on the wind blade 20. In this case, no bending moment is applied to the wind blade 20. Therefore, in the process of the controller calculating the torsional stiffness of the wind blade 20, only the data related to the torsional moment needs to be processed, and the data related to the bending moment does not need to be processed, so the amount of data processing is small.

In the torsion test system for wind turbine blades according to the second embodiment of the present disclosure shown in FIG. 4 , although there is no support rod to constrain the translational movement of the clamping portion 30, the loading arm 33 connected to the first clamp 31 is relatively fixed (for example, fixed to the ground). Therefore, during the load loading process, the clamping portion 30 will not undergo translational movement, but can only undergo rotation (the wind turbine blade 20 can only undergo torsional deformation, not bending deformation). In this case, no bending moment is applied to the wind turbine blade 20. Therefore, in the process of the controller calculating the torsional stiffness of the wind turbine blade 20, only the data related to the torsional moment needs to be processed, and the data related to the bending moment does not need to be processed, so the amount of data processing is relatively small.

In the torsion test system for wind turbine blades according to the third and fourth embodiments of the present disclosure shown in FIG. 5 and FIG. 6, there is no component to constrain the translation of the clamping portion 30, so during the load loading process, the clamping portion 30 rotates and translates (the wind turbine blade 20 undergoes torsional deformation and bending deformation). In the torsion test system shown in FIG. 6, the first clamp 31 is connected to the load sensor 70 by, for example, a rope, and then connected to the ground. The difference between the torsion test systems in FIG. 5 and FIG. 6 lies in: the loading method of the load loading portion 40 (the torsion test system in FIG. 5 is double-sided loading, while the torsion test system in FIG. 6 is single-sided loading) and the direction in which the load is loaded by the load loading portion 40 (the load loading direction in FIG. 5 is perpendicular to the direction from the pressure side to the suction side of the wind turbine blade 20, while the load loading direction in FIG. 6 is parallel to the direction from the pressure side to the suction side of the wind turbine blade 20).

Although there are differences between the torsion test systems shown in Figures 5 and 6, both torsion test systems can apply bending moment and torsion moment to the wind blade 20. In this case, in the process of the controller calculating the torsion stiffness of the wind blade 20, it is necessary to process data related to both the bending moment and the torsion moment.

In addition, if the first clamp 31 of the clamping part shown in Figure 6 is fixed to the ground through an anti-translational motion component (for example, the rope connected between the first clamp 31 and the ground is replaced by an anti-translational motion component (for example, the support rod described above)), then the resulting torsion test system prevents the clamping part from moving horizontally and can only rotate, so the wind turbine blades can only be deformed by torsion but not by bending, and the resulting torsion test system is capable of performing pure torsional torque testing.

In addition, as shown in FIGS. 3 to 6 , a conformal block matching the shape of the pressure side and the suction side of the fan blade 20 is provided inside each of the first clamp 31 and the second clamp 32. During the load loading process, the conformal block can deform to conform to the shape of the pressure side and the suction side of the fan blade 20, so that the clamping portion 30 can stably clamp the fan blade 20. For example, a first conformal block 311 is provided inside the first clamp 31, and the first conformal block 311 can conform to the shape of the pressure side of the fan blade 20. A second conformal block 321 is provided inside the second clamp 32, and the second conformal block 321 can conform to the shape of the suction side of the fan blade 20.

The torsion test method for a wind turbine blade according to the present disclosure will be described in detail below. The torsion test method comprises the following steps:

The root of the fan blade 20 is fixed to the test bench 10, and the tip of the fan blade 20 is clamped by the clamping part 30 to keep the fan blade 20 in a horizontal state;

Arrange detection components at multiple locations on the surface of the fan blade 20, and connect the detection components to the controller;

The load-applying portion 40 is connected to at least one side of the clamping portion 30, and a load causing the fan blade 20 to twist is applied to the fan blade 20 through the clamping portion 30;

The controller obtains torsional deformation data of the fan blade 20 from the detection assembly, calculates the torsional moment applied to the fan blade 20 by the load applying part 40 based on the applied load, and determines the torsional stiffness of the fan blade 20 according to the torsional moment and the torsional deformation data.

Optionally, the step of arranging the detection assembly may include: installing an inclinometer 50 on the clamping portion 30, the inclinometer 50 being used to measure the angle change of the clamping portion 30 during the loading process of the load. In addition, the step of calculating the torsional moment may include: calculating the torsional moment based on the loaded load and the angle measured by the inclinometer 50.

Optionally, the step of arranging the detection assembly may include: arranging a plurality of detection lines 61 on the surface of the fan blade 20, the plurality of detection lines 61 extending along the chord direction of the fan blade 20 and spaced apart along the span direction of the fan blade 20, the plurality of detection lines 61 being used to detect the torsional deformation degree of a plurality of cross sections of the fan blade 20. The torsional deformation data may be calculated based on the deformation difference between the cross section before deformation and the cross section after deformation at the same detection line 60 of the fan blade 20 and/or the deformation difference between two cross sections of the fan blade 20 at two adjacent detection lines 61.

By collecting the torsional deformation data of multiple cross sections, the torsional deformation of the blade surface of the entire wind turbine blade 20 can be determined. Specifically, the torsional deformation of the portion of the blade surface between two adjacent cross sections can be determined by differential analysis based on the torsional deformation of adjacent cross sections, and by combining the collected torsional deformation of multiple cross sections with the torsional deformation determined by differential analysis, the torsional deformation of the blade surface of the entire wind turbine blade 20 can be determined.

Furthermore, the detection assembly may also include a thermal imaging device, the detection line 61 may be a resistance wire and connected to a power source, and may generate heat during the loading process of the load, and the thermal imaging device may capture a thermal image of the resistance wire during the loading process of the load, and send the thermal image to the controller. The controller may analyze the received thermal image to determine the torsional deformation of the blade surface.

Furthermore, the detection assembly may also include a piezoelectric signal capturer, the detection line 61 may be formed of a piezoelectric material, and the piezoelectric signal capturer can obtain a piezoelectric signal from the detection line 61 during the loading process of the load, and send the piezoelectric signal to the controller. The controller can analyze the piezoelectric signal to determine the torsional deformation of the blade surface.

Optionally, the step of arranging the detection component may include: arranging a plurality of spots 62 on the wind blade 20, the detection component may include a camera, the camera can capture images of the wind blade 20 during the loading process, and the controller can determine the torsional deformation data of the wind blade 20 based on the captured images.

By adopting the above-mentioned torsion test system and torsion test method, the torsional stiffness of the fan blade can be accurately calculated, so as to determine whether the comprehensive performance of the blade meets the design requirements of the fan blade, avoid the problem of air elasticity and blade operation vibration of the fan blade due to insufficient stiffness, and facilitate the design and development of large-sized fan blades. In addition, by adopting the torsion test system disclosed in the present invention, the response of the fan blade under the action of load can be more comprehensively, objectively and accurately reflected, thereby improving the accuracy of torsion test simulation and torsional stiffness calculation, improving the rationality and reliability of blade design and development, and making the convergence of multiple measurement results better. In the case of using multiple detection lines to detect the torsional deformation degree of multiple sections of the fan blade, the continuity of the measurement is better, and the torsional deformation of the entire section of the fan blade can be obtained, so the measurement accuracy of the detection line is higher. In the case of detecting the torsional deformation degree of the fan blade by densely arranged spots, the torsional deformation data of multiple positions on the blade surface can be obtained, so the measurement accuracy of this method is higher.

Although some embodiments of the present disclosure have been shown and described, it will be appreciated by those skilled in the art that modifications may be made to the embodiments without departing from the principles and spirit of the present disclosure, the scope of which is defined by the claims and their equivalents.

Claims (13)

1. A torsion test system for a wind turbine blade, characterized in that the torsion test system comprises: A test bench (10) for fixing the blade root of the fan blade (20); A clamping portion (30) used for clamping the tip of the fan blade (20); A load-applying portion (40) connected to at least one side of the clamping portion (30) and used for applying a load to the fan blade (20) through the clamping portion (30) so as to cause the fan blade (20) to twist; A detection component, used for obtaining torsional deformation data at multiple positions of the fan blade (20); The controller calculates the torsional moment applied by the load applying part (40) to the fan blade (20) based on the applied load, and determines the torsional stiffness of the fan blade (20) according to the torsional moment and the torsional deformation data. 2. According to claim 1, the torsion testing system for wind blades is characterized in that the torsion testing system also includes an inclinometer (50), which is installed on the clamping part (30) and is used to measure the angle change of the clamping part (30) during the loading process of the load, and the controller calculates the torsion torque applied by the load loading part (40) to the wind blade (20) based on the loaded load and the angle measured by the inclinometer (50). 3. The torsion testing system for wind blades according to claim 1 is characterized in that the detection component includes a plurality of detection lines (61) arranged on the surface of the wind blade (20), the plurality of detection lines (61) extending along the chord direction of the wind blade (20) and spaced apart along the span direction of the wind blade (20), and the plurality of detection lines (61) are used to detect the degree of torsional deformation of multiple cross sections of the wind blade (20). 4. The torsion test system for wind turbine blades according to claim 3 is characterized in that the detection component also includes a thermal imaging device, the detection line (61) is a resistance wire and is connected to a power supply, and can generate heat during the loading process of the load, and the thermal imaging device can capture a thermal image of the resistance wire during the loading process of the load. 5. According to the torsion test system for wind turbine blades according to claim 3, it is characterized in that the detection component also includes a piezoelectric signal capturer, the detection line (61) is formed of piezoelectric material, and the piezoelectric signal capturer can obtain a piezoelectric signal from the detection line (61) during the loading process of the load. 6. The torsion testing system for wind blades according to claim 1 is characterized in that the detection component includes a camera, and a plurality of spots (62) are arranged on the surface of the wind blade (20), the camera is capable of capturing a picture of the wind blade (20) during the loading process of the load, and the controller is capable of determining the torsional deformation data of the wind blade (20) based on the captured picture. 7. The torsion test system for wind turbine blades according to claim 2, characterized in that the clamping portion (30) comprises a clamp body and a loading arm (33) extending outward from the clamp body, and the inclinometer (50) is arranged on the loading arm (33). 8. The torsion testing system for wind blades according to claim 1 is characterized in that the clamping portion (30) comprises a first clamp (31) and a second clamp (32) arranged opposite to each other, and the first clamp (31) and the second clamp (32) clamp the wind blade (20) at the pressure side and the suction side of the wind blade (20), respectively. 9. The torsion test system for wind turbine blades according to claim 8 is characterized in that the clamping portion (30) further comprises a connecting rod (34) and a support rod (35), the two ends of the connecting rod (34) are respectively connected to the first clamp (31) and the second clamp (32), and one end of the support rod (35) is connected to the connecting rod (34) and the other end of the support rod (35) is fixed. 10. The torsion testing system for wind blades according to claim 8, characterized in that a conformal block matching the shape of the pressure side and the suction side of the wind blade (20) is arranged inside each of the first fixture (31) and the second fixture (32). 11. A torsion test method for a wind turbine blade, characterized in that the torsion test method comprises the following steps: The root of the fan blade (20) is fixed to the test bench (10), and the tip of the fan blade (20) is clamped by a clamping part (30) so that the fan blade (20) is kept in a horizontal state; Arranging detection components at multiple positions on the surface of the fan blade (20), and connecting the detection components to a controller; Connecting a load-applying portion (40) to at least one side of the clamping portion (30), and applying a load causing the fan blade (20) to twist to the fan blade (20) through the clamping portion (30); The controller obtains torsional deformation data of the fan blade (20) from the detection component, calculates the torsional moment applied by the load-applying part (40) to the fan blade (20) based on the loaded load, and determines the torsional stiffness of the fan blade (20) according to the torsional moment and the torsional deformation data. 12. The torsion test method for a wind turbine blade according to claim 11, characterized in that: The step of arranging the detection assembly comprises: installing an inclinometer (50) on the clamping portion (30), the inclinometer (50) being used to measure the angle change of the clamping portion (30) during the loading process of the load, The step of calculating the torsional moment comprises: calculating the torsional moment based on the applied load and the angle measured by the inclinometer (50). 13. The torsion test method for a wind turbine blade according to claim 11, characterized in that: The step of arranging the detection assembly comprises: arranging a plurality of detection lines (61) on the surface of the fan blade (20), the plurality of detection lines (61) extending along the chord direction of the fan blade (20) and spaced apart along the span direction of the fan blade (20), the plurality of detection lines (61) being used to detect the torsional deformation degree of a plurality of cross sections of the fan blade (20); Alternatively, a plurality of spots (62) are arranged on the wind blade (20), the detection component comprises a camera, the camera is capable of capturing a picture of the wind blade (20) during the loading process of the load, and the controller is capable of determining the torsional deformation data of the wind blade (20) based on the captured picture.