Dynamic wind resistance control method for flexible tracking support

Abstract

The invention relates to the technical field of photovoltaic power generation, in particular to a control method for dynamic wind resistance of a flexible tracking support, which comprises the following steps: receiving a strong wind alarm signal and laying a photovoltaic module flat; the vibration displacement sensor calculates an amplitude peak value of the photovoltaic module and compares the amplitude peak value with an amplitude threshold; when the amplitude peak value of the photovoltaic module exceeds an amplitude threshold value, all motors run in the same direction to drive the photovoltaic module to rotate and deviate from a horizontal state; monitoring the running angle and amplitude of the photovoltaic module, and controlling the motor to stop running when conditions are met; a layered intervention wind-resistant mode is adopted, flexible adaptation can be achieved according to the wind condition and the vibration state of the photovoltaic module, the wind-resistant adaptability is higher, meanwhile, the vibration displacement sensor is used for dynamically detecting the amplitude of the photovoltaic module, the resonance risk is accurately and rapidly recognized, the angle of the photovoltaic module is adjusted, and the fault rate of the photovoltaic support is greatly reduced.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic power generation technology, and in particular to a method for controlling the dynamic wind resistance of a flexible tracking support. Background Technology

[0002] Flexible photovoltaic (PV) brackets are support devices that use high-strength steel cables, composite material cables, and other flexible materials to replace traditional rigid brackets. They fix PV modules to a specific spatial structure through a tensioning system. They have advantages such as strong spatial adaptability, flexible module arrangement, and lightweight design. They do not require a large amount of concrete and heavy steel during installation, which can effectively shorten the construction period and reduce construction costs.

[0003] Due to their inherent characteristics, flexible photovoltaic supports have a low natural frequency, making them prone to significant vibrations under wind loads. When the load frequency is close to or the same as the support's natural frequency, resonance can occur, potentially leading to module damage or structural fatigue failure. Therefore, dynamically adjusting the support's natural frequency to avoid resonance is a core issue that needs to be addressed to ensure the safety and durability of flexible supports.

[0004] Chinese invention patent application number 202411198561.7 discloses a wind-resistant adjustable mountain photovoltaic support structure. By using a pressure sensor, controller and servo motor in combination, when the photovoltaic panel body is subject to wind resistance, the photovoltaic panel body is rotated from an inclined state to a more horizontal state to reduce wind resistance.

[0005] However, the existing patented solutions only trigger the wind resistance mechanism by physically squeezing the pressure sensor by the photovoltaic panel. The triggering method is simple and lacks a resonance suppression mechanism. In long-term high-wind environments, this may lead to the breakage of the bracket weld points and the wear of the slide rail, thus shortening the service life. Summary of the Invention

[0006] The main technical problem to be solved by this invention is to provide a dynamic wind resistance control method for flexible tracking brackets. The wind resistance mode adopts a layered intervention, which can flexibly adapt to the wind conditions and the vibration state of the photovoltaic modules, making it more adaptable to wind resistance. At the same time, it uses vibration displacement sensors to dynamically detect the amplitude of the photovoltaic modules, accurately and quickly identify resonance risks and adjust the angle of the photovoltaic modules, thereby significantly reducing the failure rate of the photovoltaic brackets.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution: A method for controlling the dynamic wind resistance of a flexible tracking support, characterized by comprising the following steps: S1. The control device receives a strong wind alarm signal, controls the motor to run, and adjusts the photovoltaic modules to a horizontal position. S2. Activate the vibration displacement sensor, analyze and calculate the peak value of the photovoltaic module amplitude in each analysis cycle, and compare the peak value with the system's preset amplitude threshold. S3. When the peak amplitude of the photovoltaic module exceeds the system's preset amplitude threshold, the system enters the wind-resistant state: the drive device controls all motors to run in the same direction, causing the photovoltaic module to rotate away from the horizontal state, so as to achieve the effect of breaking resonance and reducing vibration. S4. During the adjustment process, the operating angle and amplitude of the photovoltaic module are monitored in real time. When the amplitude is less than the preset amplitude threshold or the operating angle is greater than the preset angle threshold, the drive device controls the motor to stop running and locks the current angle.

[0008] The following are further optimizations of the above technical solution by the present invention: In step S4, after the motor stops running, the vibration displacement sensor continues to detect the peak amplitude of the photovoltaic module. When the detected peak amplitude is higher than the set threshold, step S3 is repeated to adjust the angle of the photovoltaic module.

[0009] Further optimization: When the control device receives a signal indicating that the strong wind alarm signal has been cancelled, the flexible tracking bracket is deactivated from its wind-resistant state, the vibration displacement sensor stops working, and the normal tracking state is restored to enable photovoltaic power generation.

[0010] Further optimization: The step of calculating the peak amplitude of the photovoltaic module in step S2 is as follows: L1. Data Acquisition and Analysis: The vibration displacement sensor acquires the displacement of the photovoltaic module at the corresponding detection point of the sensor, transmits the information to the control system, and the control system analyzes the data to obtain the axial displacement of the current detection point. L2. Calculate the composite displacement: Calculate the straight-line distance of the current detection point relative to its initial stationary position, i.e., the instantaneous composite displacement D. 合成 ; L3. Confirm maximum displacement: Set up a data window to store the most recent N D values. 合成 The numerical value, based on the system's preset analysis period, confirms D within each period. 合成 The maximum value is the peak value of the photovoltaic module amplitude within that cycle.

[0011] Further optimization: In step L3, the size of the data window is fixed, and the newly calculated D... 合成 The values ​​are stored in the window, and the oldest data in the window is removed, completing the iteration of the data in the window.

[0012] Further optimization: In step S4, the method for monitoring the operating angle of the photovoltaic module is as follows: The control system comprehensively collects the angle data from the tilt sensor and the Hall sensor, and performs fusion calculation according to the weighting coefficient preset by the system. After filtering, the fused data is used to obtain the actual angle of the photovoltaic module. After comparing it with the target tracking angle, the deviation of the actual angle of the photovoltaic module is corrected to form a closed-loop control.

[0013] Further optimization: The working steps of the tilt sensor are as follows: R1. Initialization and zero-point calibration: Place the tilt sensor horizontally, collect the original acceleration data of the tilt sensor in the three directions of x-axis, y-axis and z-axis, and calculate the compensated triaxial acceleration data. R2. Data Acquisition and Filtering: Select the N most recently acquired compensated triaxial acceleration data sets, calculate the average value, and complete the moving average filtering; R3, Tilt Angle Calculation: Calculate the pitch angle and roll angle of the photovoltaic module.

[0014] The present invention, by adopting the above technical solution, has the following beneficial effects: This invention employs a layered intervention mode in high-wind scenarios, flexibly adapting to the wind conditions and the vibration state of the photovoltaic modules, dynamically adjusting the posture of the photovoltaic modules, resulting in stronger wind resistance and adaptability, especially suitable for complex wind environments such as mountainous and coastal areas.

[0015] This invention uses vibration displacement sensors to dynamically detect the amplitude of photovoltaic modules under strong wind warning conditions and compares it with the amplitude threshold set by the system. This allows for accurate and rapid identification of resonance risks and adjustment of the photovoltaic module angle, actively disrupting resonance conditions and significantly reducing the probability of damage to the support structure caused by resonance, such as weld breakage and cable wear.

[0016] The dynamic wind resistance control method of the present invention detects the amplitude and angle values ​​in real time during the dynamic adjustment of photovoltaic modules. When the amplitude is lower than the threshold or the angle exceeds the limit, the position is locked. This can prevent the motor from running idle or repeatedly starting and stopping when no adjustment is needed, and prevent the photovoltaic module from deflecting too much, which would cause the center of gravity of the support to shift and cause the overall structure to become unstable.

[0017] This invention obtains the real-time tilt angle of a photovoltaic module by weighted fusion of data from tilt sensors and Hall sensors, and compares this real-time tilt angle value with the theoretically calculated target tracking angle to correct the angle deviation of the photovoltaic module in a timely manner. This allows for more accurate adaptation to lighting conditions and improves power generation efficiency.

[0018] The present invention will be further described below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0019] Figure 1This is a control principle diagram of the flexible tracking support system of the present invention; Figure 2 This is a flowchart illustrating the operation of the vibration displacement sensor of the present invention. Figure 3 This is a flowchart of the dynamic wind resistance control method of the present invention. Detailed Implementation

[0020] A method for controlling the dynamic wind resistance of a flexible tracking support is implemented based on a flexible tracking support system, such as... Figure 1 As shown, the flexible tracking support system includes a main support frame that provides stable support for the overall system. A photovoltaic module is installed at the top of the main support frame. An angle adjustment actuator is installed between the main support frame and the photovoltaic module to drive the photovoltaic panel to rotate and achieve angle adjustment.

[0021] The angle adjustment actuator includes a motor, and the power output end of the motor is connected to a push rod. When the motor works, it outputs rotational power, which drives the extension end of the push rod to extend or retract, thereby driving the photovoltaic module at the top of the main support frame to adjust its angle so that the photovoltaic module can receive sunlight to the maximum extent.

[0022] The flexible tracking support system also includes a control device. A drive device is electrically connected between the control device and the angle adjustment actuator. The action commands issued by the control device are processed by the drive device and converted into drive signals to drive the motor.

[0023] The control device includes an MCU and a sensor module. The MCU has a built-in control algorithm to control the normal operation of the entire system. The sensor module includes a position information sensor, which is used to receive the installation position information of the flexible tracking bracket and complete the calculation of the current solar altitude angle; and a light sensor, which is used to sense changes in light on the photovoltaic modules to correct for the effects of cloud shading.

[0024] In this embodiment, the motor is a brushless DC motor. Three Hall sensors are installed on the motor stator at 120° intervals. The Hall sensors generate pulse signals during motor operation and transmit the signals to the MCU. The MCU records the number of pulses and, in combination with the motor reduction ratio and the lead of the push rod, can convert the number of motor cycles into the angle change of the photovoltaic module.

[0025] In this embodiment, the driving device uses a G2133 chip, which processes logic signals and converts them into driving signals, controls dead time to prevent short circuits, realizes high-low level conversion, drives high-power transistors, and also has protection functions such as output blocking in case of abnormality and pulse filtering function to ensure stable and safe operation of the motor.

[0026] The control device is equipped with a tilt sensor to detect and calculate the actual tilt angle of the photovoltaic module, assisting in the angle adjustment of the photovoltaic module. During use, the control system collects data from the tilt sensor and the Hall sensor respectively, and performs fusion calculation according to the system's preset weighting coefficient. After filtering, the fused data is used to obtain the actual angle of the photovoltaic module. The control system combines the difference between the actual angle and the target tracking angle to generate an angle adjustment command, which is sent to the motor through the drive device to complete the angle adjustment.

[0027] When fusing data from tilt sensors and Hall effect sensors, tilt sensor data is used as the primary reference for static attitude measurement to ensure long-term accuracy, while Hall effect sensor data is used as the primary reference for dynamic response to detect rapid short-term changes, ensuring the accuracy of photovoltaic module angle adjustment and improving power generation efficiency.

[0028] In this embodiment, the tilt sensor is model SC7A20. By measuring the projection of gravity components on the x, y, and z axes, the current pitch and roll angles of the object are calculated. The specific workflow is as follows: R1. Initialization and zero-point calibration: Place the tilt sensor horizontally and collect the raw acceleration data of the tilt sensor in the x-axis, y-axis and z-axis directions. Collect N sets of data continuously and calculate the zero-point offset of the three axes. In the subsequent continuous measurement process, use the raw data of each axis collected each time to subtract the zero-point offset of the corresponding axis to obtain the compensated triaxial acceleration data. R2. Data Acquisition and Filtering: Select the N most recently acquired compensated triaxial acceleration data sets, calculate the average value, and perform moving average filtering to eliminate the influence of circuit interference, slight vibrations, and other factors on the original acceleration data.

[0029] R3. Tilt Angle Calculation: Let the coordinate system of the tilt sensor be defined as follows: x-axis horizontal to the right, y-axis horizontal forward, z-axis vertical upward (opposite to the direction of gravity). Then the angle of rotation around the y-axis is the pitch angle, and the angle of rotation around the x-axis is the roll angle.

[0030] Vibration displacement sensors are installed on the steel cables of the main support frame. The vibration of the photovoltaic modules is transmitted to the vibration displacement sensors through the steel cables. The vibration displacement sensors are connected to the control system. After receiving a strong wind alarm signal, the control device activates the vibration displacement sensors to collect the vibration information of the photovoltaic modules and convert it into an electrical signal, which is then transmitted to the control system.

[0031] In this embodiment, the vibration displacement sensor is connected to the control system via RS485 communication standard. During use, the vibration displacement sensor collects vibration and displacement data (such as amplitude and displacement) of the photovoltaic module, converts it into electrical signals conforming to the protocol, and transmits them to the control system. Figure 2As shown, the specific workflow is as follows: L1. Data Acquisition and Analysis: The vibration displacement sensor acquires the displacement of the photovoltaic module at the corresponding detection point of the sensor and transmits the information to the control system. The control system analyzes the data to obtain the displacement of the current detection point on the X-axis, Y-axis and Z-axis.

[0032] The displacement obtained in step L1 is a relative displacement. The absolute displacement of the current detection point on the three coordinate axes, x, y, and z, is obtained by the cumulative calculation of the control program.

[0033] L2. Calculate the composite displacement: Calculate the straight-line distance of the current detection point relative to its initial stationary position, i.e., the instantaneous composite displacement. The specific calculation formula is as follows: D 合成 = ……………………………………………(12) In equation (12), D 合成 Let x be the instantaneous composite displacement of the current detection point, and let x, y, and z be the absolute displacements of the current detection point on the three coordinate axes, respectively.

[0034] L3. Confirm maximum displacement: Set up a data window to store the most recent N D values. 合成 The numerical value, based on the system's preset analysis period, confirms D within each period. 合成 The maximum value is the peak value of the photovoltaic module amplitude within that period, and the specific calculation formula is as follows: D max =max(D 1合成， D 2合成， ...,D N合成） ………………………………(13) In equation (13), D max Where N is the maximum displacement within the data window during the current analysis period, and D is the number of data entries stored within the data window. 1合成， D 2合成， ...,D N合成 The instantaneous composite displacement of the photovoltaic module at different times is calculated using formula (12).

[0035] In step L3, the size of the data window is fixed, meaning the number of stored data rows N is a fixed value, and the newly calculated D... 合成 The values ​​are stored in the window, and the oldest data in the window is removed, completing the iteration of the data in the window.

[0036] In normal operation, the control device analyzes and calculates the target tracking angle of the photovoltaic module at the current moment through the information collected by the sensor module, and issues action commands to control the motor to adjust the angle of the photovoltaic module using the drive device.

[0037] After the photovoltaic module completes the angle adjustment, the control system comprehensively collects the angle data from the tilt sensor and the Hall sensor, performs weighted calculations to obtain the actual angle of the photovoltaic module, compares it with the target tracking angle, and corrects the deviation of the actual angle of the photovoltaic module to form a closed-loop control, thereby improving the accuracy of the photovoltaic module angle adjustment.

[0038] When the control device detects strong winds, it sends a strong wind alarm signal to the drive device. At this time, the strong wind leveling mechanism is triggered, which rotates the photovoltaic module to a horizontal position to reduce its frontal wind area. At the same time, the vibration displacement sensor is activated to detect the vibration amplitude of the photovoltaic module in real time. When the vibration amplitude exceeds the preset threshold, it means that the flexible tracking bracket has resonated, and the system immediately enters the wind-resistant state.

[0039] like Figure 3 As shown, the dynamic wind resistance control method for a flexible tracking support according to the present invention includes the following steps: S1. The control device receives a strong wind alarm signal, controls the motor to run, and adjusts the photovoltaic modules to a horizontal position. S2. Activate the vibration displacement sensor, analyze and calculate according to the above L1-L3 steps, obtain the peak value of the photovoltaic module amplitude in each analysis cycle, and compare the peak value with the system's preset amplitude threshold. S3. When the peak amplitude of the photovoltaic module exceeds the system's preset amplitude threshold, the system enters the wind-resistant state: the drive device controls all motors to run in the same direction, causing the photovoltaic module to rotate away from the horizontal state, so as to achieve the effect of breaking resonance and reducing vibration. In step S3, the photovoltaic module rotates according to the target tracking angle calculated by the control system. When the calculated target tracking angle is greater than 0°, the photovoltaic module rotates eastward. When the calculated target tracking angle is less than 0°, the photovoltaic module rotates westward.

[0040] S4. During the adjustment process, the operating angle and amplitude of the photovoltaic module are monitored in real time. When the amplitude is less than the preset amplitude threshold or the operating angle is greater than the preset angle threshold, the drive device controls the motor to stop running and locks the current angle.

[0041] In step S4, after the motor stops running, the vibration displacement sensor continues to detect the peak amplitude of the photovoltaic module. When the detected peak amplitude is higher than the set threshold, step S3 is repeated to adjust the angle of the photovoltaic module.

[0042] When the control device receives a signal indicating that the strong wind alarm has been cancelled, the flexible tracking bracket is deactivated from its wind-resistant state, the vibration displacement sensor stops working, and the system resumes normal tracking to generate photovoltaic power.

[0043] For those skilled in the art, any changes, modifications, substitutions, and variations made to the embodiments without departing from the principles and spirit of the present invention, based on the teachings of the present invention, still fall within the protection scope of the present invention.

Claims

1. A control method of a flexible tracking support dynamic wind resistance, characterized in that, The method comprises the following steps: S1, the control device receives a strong wind warning signal, controls the motor to run, and adjusts the photovoltaic module to a horizontal state; S2, the vibration displacement sensor is enabled, the peak value of the amplitude of the photovoltaic module in each analysis period is obtained through analysis and calculation, and the peak value is compared with the amplitude threshold value preset by the system; S3, when the peak value of the amplitude of the photovoltaic module exceeds the amplitude threshold value preset by the system, the system enters the wind-resistant state: the driving device controls all the motors to run in the same direction, drives the photovoltaic module to rotate away from the horizontal state, so as to achieve the effect of destroying resonance and reducing vibration; S4, the running angle and amplitude of the photovoltaic module are monitored in real time during the adjustment process, when the amplitude is less than the preset amplitude threshold value or the running angle is greater than the preset angle threshold value, the driving device controls the motor to stop running and locks the current angle.

2. The control method of claim 1, wherein, In step S4, after the motor stops running, the vibration displacement sensor still continuously detects the amplitude peak value of the photovoltaic module, and when the detected amplitude peak value is higher than the set threshold value, the step S3 is repeated to adjust the angle of the photovoltaic module.

3. The control method of claim 1, wherein, When the control device receives a signal for canceling the strong wind warning signal, the flexible tracking support releases the wind-resistant state, the vibration displacement sensor stops being used, and the normal tracking state is restored to generate photovoltaic power.

4. The control method of claim 1, wherein, The step of calculating the amplitude peak value of the photovoltaic module in step S2 is: L1, data acquisition and analysis: the vibration displacement sensor obtains the displacement amount of the photovoltaic module at the detection point corresponding to the sensor, transmits the information to the control system, and the control system analyzes to obtain the shaft displacement amount of the current detection point; L2, calculate the synthetic displacement amount: calculate the straight line distance of the current detection point relative to its initial static position, that is, the instantaneous synthetic displacement amount D 合成 ; L3, confirm the maximum displacement amount: set a data window to store the last N data 合成 values, according to the system preset analysis period, confirm the maximum value of D 合成 in each period, that is, the peak value of the amplitude of the photovoltaic module in the period.

5. The control method of claim 4, wherein, The size of the data window is fixed in step L3, and the newly calculated D 合成 The numerical value is stored in the window, and the oldest data in the window is removed, completing the iteration of the data in the window.

6. The control method of claim 1, wherein, In step S4, the monitoring method of the running angle of the photovoltaic module is: the control system comprehensively collects the angle data of the inclination sensor and the Hall sensor, and performs fusion operation according to the weighting coefficient preset by the system, the actual angle of the photovoltaic module is obtained after the fused data is filtered, and the actual angle of the photovoltaic module is compared with the target tracking angle, and the actual angle of the photovoltaic module is corrected, to form a closed loop control.

7. The control method of claim 1, wherein the control method is a dynamic wind resistance control method of a flexible tracking support. The working steps of the inclination sensor are: R1, initialization and zero calibration: place the inclination sensor horizontally, collect the original acceleration data of the inclination sensor in the x-axis, y-axis and z-axis directions, and calculate the compensated three-axis acceleration data; R2, data acquisition and filtering: select the latest N groups of compensated three-axis acceleration data, calculate the average value, and complete the sliding average filtering; R3, inclination calculation: calculate the pitch angle and roll angle of the photovoltaic module.

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