Flexible photovoltaic support aeroelastic response wind tunnel test platform and method

Abstract

The invention discloses a flexible photovoltaic support aeroelastic response wind tunnel test platform and method, and the platform comprises a platform body which comprises a wind field simulation region and an experiment test region. A wind tunnel wedge is arranged at the front section of the incoming flow wind direction in the wind field simulation area; a flexible photovoltaic support model is arranged in the experimental test area; the flexible photovoltaic support model comprises a photovoltaic panel, a flexible photovoltaic panel support and a flexible photovoltaic panel base; the flexible photovoltaic panel base is fixed on the wind tunnel turntable; the photovoltaic panel is fixed on the flexible photovoltaic panel base through the flexible photovoltaic panel bracket; steel cables penetrate through the interior of the photovoltaic panel, and the steel cables on the two sides are connected with an electronic tension meter and a tightening device. Through the platform and the method, a real complex wind field environment can be simulated, dynamic response data of the support under different working conditions can be obtained, and a scientific basis is provided for design optimization and wind resistance improvement of the flexible photovoltaic support.

Description

Technical Field

[0001] The present invention relates to the technical field of performance testing of photovoltaic support structures, and in particular to an aeroelastic response wind tunnel testing platform and method for flexible photovoltaic support structures. Background Art

[0002] Photovoltaic brackets are an important part of photovoltaic systems. Their main function is to carry and fix photovoltaic modules and ensure the stability and long-term operation performance of photovoltaic power generation systems under complex environmental conditions. In recent years, with the increasing demand for lightweight and flexible design of photovoltaic systems, flexible photovoltaic brackets have gradually become one of the hot spots for research and development due to their excellent adaptability and economy.

[0003] Flexible photovoltaic brackets are made of materials with certain elasticity and deformability. Compared with traditional rigid brackets, they have the advantages of light weight, easy installation, and strong wind resistance. However, the structural characteristics of flexible photovoltaic brackets also make them exhibit more significant aerodynamic-structural coupling behavior under wind loads, such as aeroelastic phenomena such as vortex-induced vibration, flutter, and galloping. These phenomena may cause fatigue damage to the bracket, affect the power generation efficiency of photovoltaic modules, and may even cause structural failure of the system. Therefore, in-depth research on the dynamic characteristics of flexible photovoltaic brackets under wind is of great significance to improving the overall safety and reliability of photovoltaic systems.

[0004] At present, the research on the aerodynamic performance of photovoltaic brackets mainly focuses on numerical simulation and traditional wind tunnel tests. However, the existing technology has significant deficiencies in the following aspects: (1) Limitations of numerical simulation: Existing numerical simulation methods often require simplification of the wind field environment, bracket material properties and coupling effects, which makes it difficult to truly reflect the dynamic response characteristics of flexible brackets in complex wind fields, especially in the accurate prediction of nonlinear aerodynamic-structural coupling behavior. There are certain errors. (2) Insufficient experimental equipment: Traditional wind tunnel tests are mainly designed for rigid structures, and test equipment usually cannot meet the dynamic response requirements of flexible photovoltaic brackets. For example, existing wind tunnel equipment lacks the ability to fully measure the deformation and vibration characteristics of flexible brackets, making it difficult to truly simulate the behavior of brackets under actual wind field conditions. (3) Limited simulation capabilities of wind field environment: The wind field characteristics in the natural environment are complex, including the influence of multiple factors such as turbulence, gusts, and shear wind. Most existing wind tunnel test equipment uses uniform flow field testing, which is difficult to effectively simulate the non-uniform wind field characteristics in actual use environments. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of the prior art and provide a wind tunnel test platform and method for the aeroelastic response of a flexible photovoltaic bracket. Through this platform and method, a real complex wind field environment can be simulated, and the dynamic response data of the bracket under different working conditions can be obtained, providing a scientific basis for the design optimization and wind resistance improvement of the flexible photovoltaic bracket.

[0006] The purpose of the present invention is achieved in one aspect as follows: A method for testing the aeroelastic response of a flexible photovoltaic bracket in a wind tunnel comprises the following steps:

[0007] 1) The flexible photovoltaic bracket model is made according to the actual photovoltaic bracket at a scale ratio, and flexible materials are used to simulate the elastic characteristics and deformation behavior of the actual structure; the flexible photovoltaic bracket model includes a flexible photovoltaic panel, a flexible photovoltaic panel bracket and a flexible photovoltaic panel base; the flexible photovoltaic panel base is fixed on the wind tunnel turntable; the flexible photovoltaic panel is fixed on the photovoltaic panel base through the photovoltaic panel bracket;

[0008] 2) Install a flexible photovoltaic bracket model in the experimental test area of ​​the wind tunnel laboratory, and install an electronic tensile gauge and a tightening device on the inclined steel strands of the flexible photovoltaic system;

[0009] 3) Adjust the tightening device to apply a pre-tightening force corresponding to the actual structure to the flexible photovoltaic panel;

[0010] 4) In the wind field simulation area, the turbulence field that conforms to the actual wind field is modulated by the wind tunnel wedge and roughness element, the incoming wind field is modulated, and the hot wire anemometer and pitot tube are arranged in the experimental test area of ​​the wind tunnel to accurately obtain the flow field information;

[0011] 5) Adjust the position of the movable bracket crossbar through the electronic remote control device so that the displacement sensor laser on the crossbar is facing the reflective paper on the photovoltaic panel below;

[0012] 6) Fix the micro acceleration sensor on the back of the flexible photovoltaic panel and arrange the strain gauge at the bottom of the photovoltaic bracket;

[0013] 7) Adjust the control panel outside the wind tunnel to set the wind speed and the angle between the flexible photovoltaic panel and the incoming wind;

[0014] 8) The signal acquisition system collects instantaneous data of displacement, acceleration and strain when the photovoltaic panel vibrates;

[0015] 9) Changing the structural parameters and size parameters of the flexible photovoltaic system, measuring the aeroelastic response of various flexible photovoltaic systems; adjusting the wind speed and the angle between the flexible photovoltaic panel and the incoming wind, and repeating step 8) after the wind field is stable, until all the data under the working conditions to be tested are measured;

[0016] 10) Analyze the effective data of displacement, acceleration and stress of flexible photovoltaic bracket during wind tunnel vibration;

[0017] 11) Draw a graph to compare the displacement and acceleration response of photovoltaic panels at different spatial positions under different wind fields, different wind directions and different wind speeds;

[0018] 12) Calculate the spectrum amplitude of the acceleration and displacement of the flexible photovoltaic bracket, the pulsation root mean square of the acceleration, and the drag coefficient, lift coefficient, and torque coefficient of the flexible photovoltaic bracket based on data analysis;

[0019] 13) After data analysis and verification are completed, the test is over, the flexible photovoltaic bracket, sensor and auxiliary bracket are removed, and the test instruments and equipment are disassembled, packed and put back to their original places.

[0020] As a further limitation of the present invention, the effective data of displacement, acceleration and stress of the flexible photovoltaic bracket during wind tunnel vibration in step 10) is analyzed; specifically according to the following formula:

[0021] a max =max|a(t)| (1)

[0022] x max =maxx(t)| (2)

[0023] σ max =E·maxε(t)| (3)

[0024] Δσ=σ max -σ min (4)

[0025] In the formula, a max 、x max , σ max , σ min are the maximum acceleration, maximum displacement, maximum stress and minimum stress of the flexible photovoltaic bracket, a(t), x(t) and |ε(t)| are the measured acceleration, displacement and stress time history, E is the elastic modulus of the material, and Δσ is the stress amplitude.

[0026] Another aspect of the purpose of the present invention is achieved as follows: the platform body includes a wind field simulation area and an experimental test area; a wind tunnel wedge is arranged in the front section of the incoming wind direction in the wind field simulation area; a flexible photovoltaic bracket model is arranged in the experimental test area; the flexible photovoltaic bracket model includes a flexible photovoltaic panel, a flexible photovoltaic panel bracket and a flexible photovoltaic panel base; the flexible photovoltaic panel base is fixed on the wind tunnel turntable; the flexible photovoltaic panel is fixed on the flexible photovoltaic panel base through the flexible photovoltaic panel bracket; a steel cable passes through the interior of the flexible photovoltaic panel, and the steel cables on both sides are connected with an electronic dynamometer and a tightening device;

[0027] Guide rail brackets are installed on both sides of the experimental test area, two transverse guide rails are arranged between the guide rail brackets, two longitudinal guide rails are installed between the transverse guide rails, and a drive motor is arranged on the guide rail bracket, and the drive motor is electrically connected to the electronic remote control device.

[0028] As a further limitation of the present invention, an acceleration sensor is fixed to the back of the flexible photovoltaic panel, and a strain gauge is fixed to the flexible photovoltaic panel bracket; the acceleration sensor and the strain gauge are electrically connected to the signal acquisition system through a signal line.

[0029] As a further limitation of the present invention, a displacement sensor is provided on the longitudinal guide rail; the displacement sensor is electrically connected to the signal acquisition system via a signal line.

[0030] As a further limitation of the present invention, a hot wire anemometer and a Pitot tube are arranged in the experimental test area, and the hot wire anemometer and the Pitot tube are installed on a telescopic bracket.

[0031] As a further limitation of the present invention, reflective paper is provided on the upper surface of the flexible photovoltaic panel.

[0032] As a further limitation of the present invention, the wind tunnel wedge is connected to the dial and the rotating shaft respectively through hinges.

[0033] The present invention adopts the above technical solution, and compared with the prior art, the beneficial effects are as follows: 1) The wind test platform of the present invention realizes the displacement measurement of different positions of the flexible photovoltaic bracket by moving the bracket, and arranges acceleration sensors and strain gauges at the same time to realize real-time collection of dynamic parameters such as vibration, deformation and stress. During the aerodynamic measurement process of the photovoltaic bracket, vibration coupling interference from different wind directions is prone to occur. The present invention ensures that the vibration acceleration of the flexible photovoltaic panel in the downwind and crosswind directions does not interfere with each other by reasonably setting the installation position of the acceleration sensor, thus ensuring the singleness of the measurement data. 2) The wind tunnel wedge with adjustable angle is designed and processed to realize the adjustment of different wind profiles, turbulence intensity profiles, gust frequencies, etc., to ensure the diversity and authenticity of the flexible photovoltaic bracket model. 3) In order to measure the flexible adjustment of structural parameters (such as stiffness, damping, and mass distribution) of different flexible photovoltaic bracket models, the key components of the flexible photovoltaic bracket model (such as support rods, beams, and photovoltaic panels) are designed as detachable modules for quick replacement. The flexibility of the model stiffness parameters is improved by configuring spring components or adjustable materials. Replaceable damping materials or liquid damping devices are used to simulate the damping characteristics of different structures. A variable angle device is configured to dynamically adjust the inclination of the photovoltaic panel and study the influence of different installation angles on the aerodynamic response. The measurement of aerodynamic performance in various situations is achieved to improve test efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1Overall schematic diagram of the test platform of the present invention.

[0035] Figure 2 A schematic structural diagram of the test area of ​​the present invention.

[0036] Figure 3 Layout diagram of the flexible photovoltaic bracket model of the present invention on the wind tunnel turntable.

[0037] Figure 4 Schematic diagram of the horizontal and vertical bar remote control of the present invention.

[0038] Figure 5 Schematic diagram of the electronic dynamometer and tightening device of the present invention.

[0039] Figure 6 A top view of the wind tunnel wedge of the wind field simulation area of ​​the present invention.

[0040] Figure 7 Comparison diagram of the root mean square of the added power of the flexible photovoltaic bracket of the present invention at different wind speeds.

[0041] Figure 8 A comparison diagram of the maximum disturbance of the flexible photovoltaic support of the present invention at different wind speeds.

[0042] Among them, 1 wind field simulation area, 2 experimental test area, 3 incoming wind direction, 4 wind tunnel wedge, 5 flexible photovoltaic panel, 6 guide rail bracket, 7 transverse guide rail, 8 longitudinal guide rail, 9 drive motor, 10 flexible photovoltaic panel bracket, 11 electronic tensile gauge, 12 preload device, 13 hot wire anemometer, 14 Pitot tube, 15 reflective paper, 16 steel cable, 17 acceleration sensor, 18 telescopic bracket, 19 displacement sensor, 20 signal line, 21 signal acquisition system, 22 electronic remote control device, 23 wind tunnel turntable, 24 flexible photovoltaic panel base, 25 strain gauge, 26 rotating shaft, 27 dial. DETAILED DESCRIPTION

[0043] like Figure 1 A flexible photovoltaic bracket aeroelastic response wind tunnel test platform shown in the figure includes a platform body, which includes a wind field simulation area 1 and an experimental test area 2; a wind tunnel wedge 4 is arranged in the front section of the incoming wind direction 3 in the wind field simulation area 1, and the wind tunnel wedge 4 is respectively connected to a dial 27 and a rotating shaft 26 through hinges; the wind tunnel wedge 4 is adjusted to form a wind profile and a turbulence profile that conform to the natural environment or extreme climate conditions;

[0044] like Figure 2As shown, a flexible photovoltaic bracket model is set in the experimental test area 2; the flexible photovoltaic bracket model includes a flexible photovoltaic panel 5, a flexible photovoltaic panel bracket 10 and a flexible photovoltaic panel base 24; the flexible photovoltaic panel base 24 is fixed on the wind tunnel turntable 23; the flexible photovoltaic panel 5 is fixed on the flexible photovoltaic panel base 24 through the flexible photovoltaic panel bracket 10; the angle of the wind tunnel turntable 23 is adjusted to change the angle between the turbulent wind and the flexible photovoltaic panel 5, and the interior of the flexible photovoltaic panel 5 passes through the steel cable 16, and the steel cables 16 on both sides are connected to the electronic dynamometer 11 and the tightening device 12; Figure 5 As shown, different pre-tightening forces can be applied to the electronic dynamometer 16 by the tightening device 12, and the pre-tightening force can be directly read from the electronic dynamometer 11;

[0045] A hot-wire anemometer 13 and a pitot tube 14 are arranged in the experimental test area 2, and the hot-wire anemometer 13 and the pitot tube 14 are installed on a telescopic bracket 18; the height of the hot-wire anemometer 13 and the pitot tube 14 is adjusted by the telescopic bracket 18 so that the height is greater than three times the height of the photovoltaic panel, and the wind speed, dynamic pressure and static pressure are measured without affecting the aerodynamic characteristics of the model;

[0046] Guide rail brackets 6 are installed on both sides of the experimental test area 2, two transverse guide rails 7 are arranged between the guide rail brackets 6, two longitudinal guide rails 8 are installed between the transverse guide rails 7, and a drive motor 9 is arranged on the guide rail bracket 6, and the drive motor 9 is electrically connected to the electronic remote control device 22; Figure 4 As shown, the driving motor 9 is controlled by an electronic remote control device 22 outside the wind tunnel to enable the two transverse guide rails 7 to achieve transverse movement and the two longitudinal guide rails 8 to achieve longitudinal movement;

[0047] A displacement sensor 19 is installed on each of the two longitudinal guide rails 8. The position of the guide rails is adjusted so that the laser emitted by the displacement sensor 19 shines on the reflective paper 15 on the upper surface of the flexible photovoltaic panel 5 directly below, so that the displacement data of the flexible photovoltaic panel 5 during the vibration process can be measured more accurately.

[0048] like Figure 3 As shown, an acceleration sensor 17 is fixed on the back of the flexible photovoltaic panel 5, which can measure the acceleration data of the photovoltaic panel 5 during the vibration process. A strain gauge 25 is fixed on the flexible photovoltaic panel bracket 10, which can measure the stress generated by the photovoltaic bracket during the vibration process; the data of the displacement sensor 19, the acceleration sensor 17 and the strain gauge 25 are connected to the signal acquisition system 21 through the signal line 20 to realize data collection.

[0049] A wind tunnel test method for aeroelastic response of a flexible photovoltaic bracket comprises the following steps:

[0050] 1) The flexible photovoltaic bracket model is made according to the actual photovoltaic bracket at a scale ratio, and the scale ratio is designed and processed in the range of 1:50 to 1:20. Flexible materials are used to simulate the elastic properties and deformation behavior of the actual structure. After processing, the natural frequency of the measured model meets the vibration characteristics of the actual model;

[0051] 2) Install a flexible photovoltaic bracket model in the experimental test area of ​​the wind tunnel laboratory, place the flexible photovoltaic bracket model that meets the structural vibration characteristics on the wind tunnel turntable in the experimental test area, and install an electronic tensile gauge and a tightening device on the inclined steel strand of the flexible photovoltaic system;

[0052] 3) Adjust the tightening device to apply a pre-tightening force corresponding to the actual structure to the flexible photovoltaic panel;

[0053] 4) In the wind field simulation area, the turbulence field that conforms to the actual wind field is modulated by the wind tunnel wedge and roughness element, the incoming wind field is modulated, and the hot wire anemometer and pitot tube are arranged in the experimental test area of ​​the wind tunnel to accurately obtain the flow field information;

[0054] 5) Adjust the position of the movable bracket crossbar through the electronic remote control device so that the displacement sensor laser on the crossbar is facing the reflective paper on the flexible photovoltaic panel below;

[0055] 6) Fix the micro acceleration sensor on the back of the flexible photovoltaic panel and arrange the strain gauge at the bottom of the photovoltaic bracket for real-time stress parameters;

[0056] 7) Adjust the control panel outside the wind tunnel to set the wind speed and the angle between the flexible photovoltaic panel and the incoming wind;

[0057] 8) The signal acquisition system collects instantaneous data of displacement, acceleration and strain when the photovoltaic panel vibrates;

[0058] 9) Changing the structural parameters and size parameters of the flexible photovoltaic system, measuring the aeroelastic response of various flexible photovoltaic systems; adjusting the wind speed and the angle between the photovoltaic panel and the incoming wind, and repeating step 8) after the wind field is stable, until all the data under the working conditions to be tested are measured;

[0059] 10) Analyze the effective data of displacement, acceleration and stress of flexible photovoltaic bracket during wind tunnel vibration;

[0060] The maximum displacement, acceleration and stress amplitude of the flexible photovoltaic bracket during wind tunnel vibration are analyzed according to the following formulas:

[0061] a max =max|a(t)| (1)

[0062] x max =maxx(t)| (2)

[0063] σ max=E·maxε(t)| (3)

[0064] Δσ=σ max -σ min (4)

[0065] In the formula, a max 、x max , σ max , σ min are the maximum acceleration, maximum displacement, maximum stress and minimum stress of the flexible photovoltaic bracket, a(t), x(t) and |ε(t)| are the measured acceleration, displacement and stress time history, E is the elastic modulus of the material, and Δσ is the stress amplitude.

[0066] 11) Draw a graph to compare the displacement and acceleration response of photovoltaic panels at different spatial positions under different wind fields, different wind directions and different wind speeds;

[0067] like Figure 7 The figure shows the acceleration root mean square comparison of the flexible photovoltaic bracket of the invention under different wind speeds. The wind speed of the wind field in the experiment is 5m / s~15m / s (corresponding to the actual wind speed of 15m / s~45m / s), the sampling frequency of the pressure scanning valve and the acceleration is 1000Hz, the sampling time is 60s, the horizontal axis is the different wind speeds, and the vertical axis is the acceleration root mean square of different positions of the photovoltaic panel. Figure 7 It can be seen that the data obtained by using the measuring device of the present invention can better reflect the change law of the acceleration of the flexible photovoltaic at different wind speeds and spatial positions.

[0068] like Figure 8 As shown in the figure, the maximum disturbance comparison diagram of the flexible photovoltaic bracket of the present invention under different wind speeds. The wind speed of the wind field in the experiment is 5m / s to 15m / s, the sampling frequency of the pressure scanning valve and the displacement sensor is 1000Hz, the sampling time is 60s, the horizontal axis is different wind speeds, and the vertical axis is the maximum deflection of different positions of the photovoltaic panel. Figure 8 It can be seen that the data obtained by using the measuring device of the present invention can better reflect the variation pattern of the maximum disturbance of flexible photovoltaics at different wind speeds and spatial positions.

[0069] 12) Calculate the spectrum amplitude of the acceleration and displacement of the flexible photovoltaic bracket, the pulsation root mean square of the acceleration, and the drag coefficient, lift coefficient, and torque coefficient of the flexible photovoltaic bracket based on data analysis;

[0070] According to equations (5) and (6), the acceleration and displacement signals are transformed by Fourier transform to calculate the frequency spectrum amplitude of the acceleration and displacement of the flexible photovoltaic bracket.

[0071]

[0072] Where A(f) and X(f) are the frequency spectrum amplitudes of acceleration and displacement, respectively, and f is the frequency.

[0073] The pulsation root mean square of acceleration is calculated according to formula (7) to evaluate the overall intensity of vibration;

[0074]

[0075] In the formula, a RMS is the pulsation root mean square of acceleration, and T is the time window.

[0076] According to formulas (8), (9) and (10), the drag coefficient, lift coefficient and torque coefficient of the flexible photovoltaic bracket are calculated respectively;

[0077]

[0078] In the formula, C D , C L and C M are the drag coefficient, lift coefficient, and torque coefficient respectively, ρ is the air density, A is the windward area, V is the incoming wind speed, and F D 、F L , M are the drag, lift and torque measured respectively.

[0079] 13) After data analysis and verification are completed, the test is over, the flexible photovoltaic bracket, sensor and auxiliary bracket are removed, and the test instruments and equipment are disassembled, packed and put back to their original places.

[0080] The present invention provides a wind tunnel test platform and method for aeroelastic response of a flexible photovoltaic bracket, which adjusts the size and angle of the wind tunnel wedge to reproduce the dynamic changes of typhoon wind speed in different stages, including the wind speed characteristics of the typhoon eye, eyewall area and peripheral wind field. The bracket is designed and adjusted in the wind tunnel test section to complete wind field measurements at different heights, and further comprehensively evaluate the vibration characteristics of the flexible photovoltaic bracket under typhoon conditions.

[0081] The key components of the flexible photovoltaic bracket model (such as support rods, beams, and photovoltaic panels) are designed as detachable modules to facilitate quick replacement, improve the flexibility of the model's stiffness parameters, adapt to a variety of photovoltaic bracket designs, support a variety of parametric studies, and help evaluate the design optimization effect.

[0082] Calibrate the experimental data with the computational fluid dynamics (CFD) simulation results to verify the accuracy of the numerical model; establish a structural dynamics model based on the experimental data, and optimize the photovoltaic bracket design in combination with the fluid-solid coupling theory; configure the experimental data interface to support the direct import of experimental results into the design software for optimization analysis. Improve the theoretical value of the experimental results and provide all-round support for the design of flexible photovoltaic brackets; optimize the collaborative process between experiments and design and shorten the product development cycle.

[0083] A six-degree-of-freedom force measurement sensor can be arranged at the bottom of the photovoltaic bracket to measure the wind load (lift, drag, torque, etc.) on the photovoltaic bracket. The wireless data acquisition system is integrated to simplify the wiring difficulty through wireless transmission technology; an artificial intelligence-based dynamic data processing algorithm is introduced to automatically identify vibration modes, resonance points and key wind load characteristics; a high-frequency data acquisition module is configured to support acquisition frequencies of more than 10kHz to capture high-frequency aerodynamic vibration phenomena. Improve test accuracy and efficiency, adapt to complex dynamic response test requirements, simplify experimental operation procedures, and reduce the impact of manual intervention.

[0084] According to different environmental conditions and test requirements, an adjustable temperature control system can be configured to simulate the aerodynamic response of photovoltaic brackets under different temperature conditions, and a rainfall simulation system can be introduced to study the wind-rain coupling effect of photovoltaic brackets under rainfall conditions; an adjustable surface roughness module can be added to simulate different terrain environments (such as mountains, plains, and coasts) by adjusting the roughness of the wind tunnel floor, providing more real-life test conditions, further expanding the scope of experimental research, and providing a scientific basis for bracket design optimization under different environments.

[0085] The present invention is not limited to the above-mentioned embodiments. On the basis of the technical solution disclosed in the present invention, technicians in this field can make some substitutions and deformations to some technical features therein according to the disclosed technical content without creative labor, and these substitutions and deformations are all within the protection scope of the present invention.

Claims

1. A wind tunnel test method for aeroelastic response of a flexible photovoltaic bracket, characterized in that: The following steps are involved: 1) The flexible photovoltaic bracket model is made according to the actual photovoltaic bracket at a scaled ratio, and flexible materials are used to simulate the elastic characteristics and deformation behavior of the actual structure; the flexible photovoltaic bracket model includes a flexible photovoltaic panel, a flexible photovoltaic panel bracket and a flexible photovoltaic panel base; the flexible photovoltaic panel base is fixed on the wind tunnel turntable; the flexible photovoltaic panel is fixed on the flexible photovoltaic panel base through the photovoltaic panel bracket; 2) Install a flexible photovoltaic bracket model in the experimental test area of ​​the wind tunnel laboratory, and install an electronic tensile gauge and a tightening device on the inclined steel strands of the flexible photovoltaic system; 3) Adjust the tightening device to apply a pre-tightening force corresponding to the actual structure to the flexible photovoltaic panel; 4) In the wind field simulation area, the turbulence field that conforms to the actual wind field is modulated by the wind tunnel wedge and roughness element, the incoming wind field is modulated, and the hot wire anemometer and pitot tube are arranged in the experimental test area of ​​the wind tunnel to accurately obtain the flow field information; 5) Adjust the position of the movable bracket crossbar through the electronic remote control device so that the displacement sensor laser on the crossbar is facing the reflective paper on the flexible photovoltaic panel below; 6) Fix the micro acceleration sensor on the back of the flexible photovoltaic panel and arrange the strain gauge at the bottom of the flexible photovoltaic bracket; 7) Adjust the control panel outside the wind tunnel to set the wind speed and the angle between the flexible photovoltaic panel and the incoming wind; 8) The signal acquisition system collects instantaneous data of displacement, acceleration and strain when the photovoltaic panel vibrates; 9) Changing the structural parameters and size parameters of the flexible photovoltaic system, measuring the aeroelastic response of various flexible photovoltaic systems; adjusting the wind speed and the angle between the photovoltaic panel and the incoming wind, and repeating step 8) after the wind field is stable, until all the data under the working conditions to be tested are measured; 10) Analyze the effective data of displacement, acceleration and stress of flexible photovoltaic bracket during wind tunnel vibration; 11) Draw a graph to compare the displacement and acceleration response of photovoltaic panels at different spatial positions under different wind fields, different wind directions and different wind speeds; 12) Calculate the spectrum amplitude of the acceleration and displacement of the flexible photovoltaic bracket, the pulsation root mean square of the acceleration, and the drag coefficient, lift coefficient, and torque coefficient of the flexible photovoltaic bracket based on data analysis; 13) After data analysis and verification are completed, the test is over, the flexible photovoltaic bracket, sensor and auxiliary bracket are removed, and the test instruments and equipment are disassembled, packed and put back to their original places.

2. A wind tunnel test method for aeroelastic response of a flexible photovoltaic bracket according to claim 1, characterized in that: The effective data of displacement, acceleration and stress of the flexible photovoltaic bracket during wind tunnel vibration are analyzed in step 10); specifically according to the following formula: a max =max | a(t) | (1) x max =maxx(t) | (2) s max =E·maxε(t) | (3) Ds = s max -s min (4) In the formula, a max 、x max , σ max , σ min are the maximum acceleration, maximum displacement, maximum stress and minimum stress of the flexible photovoltaic bracket, a(t), x(t) and | ε(t) | are the measured acceleration, displacement and stress time history, E is the elastic modulus of the material, and Δσ is the stress amplitude.

3. A flexible photovoltaic bracket aeroelastic response wind tunnel test platform, comprising a platform body, characterized in that: The platform body comprises a wind field simulation area (1) and an experimental test area (2); a wind tunnel wedge (4) is arranged in the front section of the incoming wind direction (3) in the wind field simulation area (1); a flexible photovoltaic bracket model is arranged in the experimental test area (2); the flexible photovoltaic bracket model comprises a flexible photovoltaic panel (5), a flexible photovoltaic panel bracket (10) and a flexible photovoltaic panel base (24); the flexible photovoltaic panel base (24) is fixed on the wind tunnel turntable (23); the flexible photovoltaic panel (5) is fixed on the flexible photovoltaic panel base (24) through the flexible photovoltaic panel bracket (10); a steel cable (16) passes through the interior of the flexible photovoltaic panel (5), and the steel cables (16) on both sides are connected with an electronic dynamometer (11) and a tightening device (12); Guide rail brackets (6) are installed on both sides of the experimental test area (2), two transverse guide rails (7) are arranged between the guide rail brackets (6), two longitudinal guide rails (8) are installed between the transverse guide rails (7), and a drive motor (9) is arranged on the guide rail bracket (6), and the drive motor (9) is electrically connected to the electronic remote control device (22).

4. A flexible photovoltaic bracket aeroelastic response wind tunnel test platform according to claim 3, characterized in that: An acceleration sensor (17) is fixed on the back of the flexible photovoltaic panel (5), and a strain gauge (25) is fixed on the flexible photovoltaic panel bracket (10); the acceleration sensor (17) and the strain gauge (25) are electrically connected to a signal acquisition system (21) via a signal line (20).

5. The flexible photovoltaic bracket aeroelastic response wind tunnel test platform according to claim 3, characterized in that: A displacement sensor (19) is provided on the longitudinal guide rail (8); the displacement sensor (19) is electrically connected to a signal acquisition system (21) via a signal line (20).

6. A flexible photovoltaic bracket aeroelastic response wind tunnel test platform according to claim 3, characterized in that: A hot wire anemometer (13) and a Pitot tube (14) are arranged in the experimental test area (2), and the hot wire anemometer (13) and the Pitot tube (14) are installed on a telescopic bracket (18).

7. A flexible photovoltaic bracket aeroelastic response wind tunnel test platform according to claim 3, characterized in that: The upper surface of the flexible photovoltaic panel (5) is provided with reflective paper (15).

8. The aeroelastic response wind tunnel test platform for flexible photovoltaic brackets according to claim 3 is characterized in that: The wind tunnel wedge (4) is respectively connected to the scale plate (27) and the rotating shaft (26) through hinges.

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