An operating status detection system based on wind turbine blades

Abstract

The present invention discloses an operation status detection system based on wind turbine blades, which relates to the technical field of torque detection, including a main shaft rotatably arranged on an external mounting seat, wherein a torque sensor is provided at one end of the main shaft, an eccentric wheel is movably sleeved on the outer wall of the main shaft through a bearing, an annular guide rail is provided on the outside of the main shaft, the annular guide rail is fixedly connected to the side wall of the mounting seat of the main shaft, a friction seat is provided on one side of the eccentric wheel, a pre-tightening block is provided on the bottom of the friction seat, the friction seat contacts the outer wall of the eccentric wheel, a permanent magnet is installed on the friction seat, a Hall sensor is provided on one side of the friction seat, a moving mechanism is movably installed on the annular guide rail, a moving seat is fixedly installed on the moving mechanism, a rolling abutment assembly is provided in the moving seat, and the rolling abutment assembly includes a mounting block movably connected to the inner wall of the moving seat through a thread. The present invention has the characteristic of long detection time.

Description

Technical Field

[0001] The present invention relates to the technical field of torque detection, and in particular to an operating status detection system based on wind turbine blades. Background Art

[0002] Torque is a key indicator of wind turbine blade health. Monitoring the torque exerted by wind on blades can help assess turbine performance. Torque monitoring can also help identify potential faults, such as gearbox wear, blade damage, or other mechanical failures.

[0003] Existing blade actuation torque detection often uses direct torque sensor detection methods. Depending on the structure, detection methods are adopted, such as central shaft type, sprocket type, and embedded type. However, direct measurement methods often rely on mechanical transmission. As the wind turbine continues to operate, the rotating parts continue to wear and loosen, which will cause the measurement results to deviate more and more. Regular maintenance by maintenance personnel is required before the detection results can be used again. The detection results are not very timely. The blade shaft of the wind turbine is at a very high position, and the maintenance cost is high. If the maintenance is only carried out to improve the torque detection accuracy, it is not cost-effective. Therefore, it is necessary to design a wind turbine blade operation status detection system with long detection time. Summary of the Invention

[0004] The purpose of the present invention is to provide an operating status detection system based on wind turbine blades to solve the problems raised in the above background technology.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: a wind turbine blade operation status detection system, comprising a main shaft rotatably arranged on an external mounting seat, a torque sensor being arranged at one end of the main shaft, an eccentric wheel being movably sleeved on the outer wall of the main shaft through a bearing, an annular guide rail being arranged on the outside of the main shaft, the annular guide rail being fixedly connected to the side wall of the mounting seat of the main shaft, a friction seat being arranged on one side of the eccentric wheel, a pre-tightening block being arranged at the bottom of the friction seat, the friction seat being in contact with the outer wall of the eccentric wheel, a permanent magnet being arranged on the friction seat, a Hall sensor being arranged on one side of the friction seat, a moving mechanism being movably mounted on the annular guide rail, a moving seat being fixedly mounted on the moving mechanism, and a rolling support assembly being arranged in the moving seat.

[0006] According to the above technical solution, the rolling support assembly includes a mounting block that is movably connected to the inner wall of the movable seat by a thread, a butterfly spring and a distance sensor are installed on the top of the mounting block, a roller bracket is installed on the top of the butterfly spring, a roller is rotatably installed on the roller bracket, the roller is in contact with the outer wall of the eccentric wheel, and the annular guide rail and the rotation center of the main shaft are in a straight line.

[0007] According to the above technical solution, blades are installed on one end of the main shaft in a circumferential distribution, and pressure strain gauges are provided between the blades and the inner wall of the main shaft.

[0008] According to the above technical solution, the device further includes a resultant force direction determination module, a rotation angle calculation module, an output voltage recording module, and a torque calculation module, wherein the resultant force direction determination module is electrically connected to the pressure strain gauge through a control system, the rotation angle calculation module is electrically connected to the distance sensor through a control system, the output voltage recording module is electrically connected to the Hall sensor through a control system, and the torque calculation module is electrically connected to the output voltage recording module;

[0009] The resultant force direction determination module is used to calculate the resultant force of the wind acting on the blade based on the pressure detection results of each pressure strain gauge; the rotation angle calculation module is used to calculate the rotation angle of the eccentric wheel based on the deformation of the butterfly spring; the output voltage recording module is used to count the output voltage of the Hall sensor at different detection times; and the torque calculation module is used to detect the torque of the main shaft based on the output voltage change of the Hall sensor.

[0010] According to the above technical solution, the working method of the system is:

[0011] S1. Before the wind turbine is put into operation, a known vertical force is applied to a single blade, and the computational relationship between the output voltage of the Hall sensor and the torque of the main shaft is determined based on the state of the eccentric wheel;

[0012] S2. When the wind turbine is maintained and running, the main shaft torque is directly detected by using a torque sensor and indirectly detected by using a Hall sensor;

[0013] S3. Adjust the weights of the direct detection and indirect detection results according to the operating time. When the difference between the two results is too large, stop the torque detection and remind maintenance. After the next wind turbine maintenance is completed, the operating time is reset and the adjustment is restarted.

[0014] According to the above technical solution, the specific steps of S1 are:

[0015] S1-1. When the blades are installed, no force is applied to the blades first, so that the moving mechanism drives the moving seat to the lowest end of the annular guide rail. At this time, the butterfly spring has an initial deformation because the roller contacts the bottom of the eccentric wheel. Provide preload force for the eccentric wheel, so that the elastic coefficient of the butterfly spring is , the preload block always applies a constant upward support force to the friction seat , calculated based on the torque balance ,in For support Horizontal distance from the eccentric wheel, The rotation center of the eccentric Rotation center of the spindle distance;

[0016] S1-2: At this time, one of the blades is in a horizontal state, and a vertical downward force is applied to the horizontal blade. ,at this time Can be converted into a vertical downward force acting on the main axis with a magnitude of Pressure and torque combination of, and ,in is the force The force point of the blade distance, and torque The butterfly spring cannot be transmitted to the eccentric wheel, and the butterfly spring generates an upward supporting force on the eccentric wheel due to the pressure. ,in is the deformation of the butterfly spring, so according to the torque balance ;

[0017] S1-3, with The increase of will make the friction seat move upward slightly until the preload block is separated from the friction seat. , making the eccentric wheel rotate compared to when it is stationary Angle, at this time ,because Very small, the permanent magnet moves with the rotation of the eccentric wheel, and the magnetic field it generates also moves around Rotation , that is, the relative position change in the magnetic field is ,in For Hall sensor and The horizontal distance, the output voltage change value of the Hall sensor ,in is the relative position change conversion coefficient, so .

[0018] According to the above technical solution, the specific steps of S2 are:

[0019] S2-1. Each blade 2 rotates in a circular motion under the action of wind. The forces detected by the three pressure strain gauges 3 are 、 、 , we can get the combined force of the three , The size of the torque cannot be calculated, only considering direction, will Equivalent to S1 , but the direction is not vertically downward, but according to 、 、 It depends on the size of the three;

[0020] S2-2, in order to maintain the reaction force provided by the roller 71 to the eccentric wheel 4 On the same line, the driving mechanism 73 quickly moves the moving seat 7 to The torque of spindle 1 is calculated again according to the steps in S1. ;

[0021] S2-3, fixed time interval 、 、 The sizes of the three are counted and the Reselect the direction and then Adjust the position of the movable seat 7 in the direction of the axis, and obtain the torque of the spindle 1 at different times at fixed intervals. .

[0022] According to the above technical solution, the specific step S3 is to directly obtain the direct measurement torque of the main shaft 1 at the current time through the torque sensor 8. , and the torque obtained by indirect measurement For comparison, if ,in If the torque difference threshold is reached, the torque detection will be stopped and maintenance will be prompted. The operation time of the wind turbine will be recorded after each maintenance. , the final torque value used ,in is always 1, and and Inversely proportional.

[0023] Compared with the prior art, the beneficial effects achieved by the present invention are as follows: the present invention adopts a method combining direct detection and indirect detection results, adopts direct detection results in a short time after the maintenance is completed, increases the weight ratio of indirect detection results for a long time, and improves the accuracy of detection results throughout the entire time. When performing indirect measurement, a combination of eccentric wheels, butterfly springs and Hall sensors is used to indirectly detect the wind-driven torque using the principle of torque balance. This detection method can reduce dependence on direct mechanical transmission, maintain a certain detection accuracy even when rotating parts continue to wear and loosen, and reduce maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0025] Figure 1 It is a schematic diagram of the overall module structure of the present invention;

[0026] Figure 2 This is a schematic diagram of the installation of the friction seat and the movable seat of the present invention;

[0027] Figure 3 It is a schematic diagram of the indirect detection principle of the present invention;

[0028] 1. Main shaft; 2. Blade; 3. Pressure strain gauge; 4. Eccentric wheel; 5. Annular guide rail; 6. Friction seat; 61. Preload block; 62. Hall sensor; 7. Moving seat; 71. Roller; 72. Roller bracket; 73. Moving mechanism; 74. Butterfly spring; 75. Mounting block; 76. Distance sensor; 8. Torque sensor. DETAILED DESCRIPTION

[0029] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0030] See also Figure 1-Figure 3 The present invention provides a technical solution: a running status detection system based on wind turbine blades, comprising a main shaft 1 rotatably arranged on an external mounting seat, a torque sensor 8 being arranged at one end of the main shaft 1, an eccentric wheel 4 being movably sleeved on the outer wall of the main shaft 1 through a bearing, an annular guide rail 5 being arranged on the outside of the main shaft 1, the annular guide rail 5 being fixedly connected to the side wall of the mounting seat of the main shaft 1, a friction seat 6 being arranged on one side of the eccentric wheel 4, a pre-tightening block 61 being arranged on the bottom of the friction seat 6, the friction seat 6 being in contact with the outer wall of the eccentric wheel 4, a permanent magnet being mounted on the friction seat 6, a Hall sensor 62 being arranged on one side of the friction seat 6, a moving mechanism 73 being movably mounted on the annular guide rail 5, a moving seat 7 being fixedly mounted on the moving mechanism 73, and a rolling abutting assembly being arranged in the moving seat 7; the friction seat 6 and the rolling abutting assembly giving torques in opposite directions to the eccentric wheel 4, both play a driving role on the eccentric wheel 4;

[0031] The rolling abutment assembly includes a mounting block 75 movably connected to the inner wall of the movable seat 7 by a thread. A butterfly spring 74 and a distance sensor 76 are mounted on the top of the mounting block 75. A roller bracket 72 is mounted on the top of the butterfly spring 74. A roller 71 is rotatably mounted on the roller bracket 72. The roller 71 contacts the outer wall of the eccentric wheel 4, and the rotation center of the annular guide rail 5 and the main shaft 1 are in a straight line. The roller 71 abuts against the eccentric wheel 4, imparting an eccentric rotational torque to the eccentric wheel 4. When the butterfly spring 74 is compressed, it generates an upward reaction force and deforms, allowing the distance sensor 76 to sense the change in distance and thus measure the degree of deformation of the butterfly spring 74.

[0032] Blades 2 are installed in a circumferential distribution at one end of the main shaft 1, and pressure strain gauges 3 are provided between the blades 2 and the inner wall of the main shaft 1; the pressure strain gauges 3 are used to detect the wind force acting on each blade 2 in real time, which facilitates the calculation of the resultant force.

[0033] It also includes a resultant force direction determination module, a rotation angle calculation module, an output voltage recording module, and a torque calculation module. The resultant force direction determination module is electrically connected to the pressure strain gauge 3 through a control system, the rotation angle calculation module is electrically connected to the distance sensor 76 through a control system, the output voltage recording module is electrically connected to the Hall sensor 62 through a control system, and the torque calculation module is electrically connected to the output voltage recording module;

[0034] The resultant force direction determination module is used to calculate the resultant force of the wind acting on the blade 2 based on the pressure detection results of each pressure strain gauge 3. The rotation angle calculation module is used to calculate the rotation angle of the eccentric wheel 4 based on the deformation of the butterfly spring. The output voltage recording module is used to count the output voltage of the Hall sensor 62 at different detection times. The torque calculation module is used to detect the torque of the main shaft 1 based on the output voltage change of the Hall sensor 62.

[0035] The system works as follows:

[0036] S1. Before the wind turbine is put into operation, a known vertical force is applied to a single blade 2, and the computational relationship between the output voltage of the Hall sensor 62 and the torque of the main shaft 1 is determined based on the state of the eccentric wheel 4.

[0037] S2. When the wind turbine is maintained and in operation, the torque sensor 8 is used to directly detect the torque of the main shaft 1, and the Hall sensor 62 is used to indirectly detect the main shaft torque;

[0038] S3. Adjust the weights of the direct and indirect detection results based on the operating time. If the difference between the two results is too large, stop torque detection and prompt maintenance. After the next wind turbine maintenance is completed, reset the operating time and restart the adjustment.

[0039] The specific steps of S1 are:

[0040] S1-1. When the blade 2 is installed, no force is applied to the blade 2, so that the moving mechanism 73 drives the moving seat 7 to move to the lowest end of the annular guide rail 5. At this time, the butterfly spring 74 has an initial deformation because the roller 71 contacts the bottom of the eccentric wheel 4. Provide preload force for eccentric wheel 4, so that the elastic coefficient of butterfly spring 74 is The preload block 61 always exerts a constant upward support force on the friction seat 6 , calculated based on the torque balance ,in For support The horizontal distance from the eccentric wheel 4, The rotation center of the eccentric wheel 4 Rotation center of spindle 1 distance;

[0041] S1-2: At this time, one of the blades 2 is placed in a horizontal state, and a vertical downward force is applied to the blade 2 in the horizontal state. ,at this time can be converted into a vertical downward force acting on the main axis 1 and having a magnitude of Pressure and torque combination of, and ,in is the force The force application point of blade 2 is distance, and torque The butterfly spring 74 generates an upward supporting force on the eccentric wheel 4 due to the pressure. ,in is the deformation amount of the butterfly spring 74, so according to the torque balance ;

[0042] S1-3, with The increase of will cause the friction seat 6 to move upward slightly until the preload block 61 is separated from the friction seat 6. , so that the eccentric wheel 4 rotates compared to when it is stationary Angle, at this time ,because The displacement of the detection end of the Hall sensor 62 in the magnetic field is approximately . Since the permanent magnet moves with the rotation of the eccentric wheel 4, the magnetic field it generates also moves around Rotation , that is, the relative position change in the magnetic field is ,in The Hall sensor 62 and The horizontal distance, the output voltage change value of the Hall sensor 62 ,in is the relative position change conversion coefficient, so ;

[0043] By detecting the voltage of the Hall sensor 62, the current torque of the main shaft 1 can be detected in real time, and the operational relationship between the two is proportional, which makes the calculation more convenient. Although the indirect measurement method is not as direct and effective as the direct detection in the early stage, its detection accuracy will exceed that of the direct detection over time, and it is suitable for situations where wind turbines require less maintenance.

[0044] The specific steps of S2 are:

[0045] S2-1. Each blade 2 rotates in a circular motion under the action of wind. The forces detected by the three pressure strain gauges 3 are 、 、 , we can get the combined force of the three , The size of the torque cannot be calculated, only considering direction, will Equivalent to S1 , but the direction is not vertically downward, but according to 、 、 It depends on the size of the three;

[0046] S2-2, in order to maintain the reaction force provided by the roller 71 to the eccentric wheel 4 On the same line, the driving mechanism 73 quickly moves the moving seat 7 to The torque of spindle 1 is calculated again according to the steps in S1. ;

[0047] S2-3, fixed time interval 、 、 The sizes of the three are counted and the Reselect the direction and then Adjust the position of the movable seat 7 in the direction of the axis, and obtain the torque of the spindle 1 at different times at fixed intervals. ;

[0048] Through this design of real-time adjustment of the position of the movable seat 7, it is not limited to the situation where the blade 2 is subjected to a vertical downward force, but the corresponding reverse support force direction and force point are adjusted according to the combined force exerted on each blade 2, making the detection more suitable for the operating status detection of the wind turbine blades.

[0049] Specifically, S3 directly obtains the current measured torque of the main shaft 1 through the torque sensor 8. , and the torque obtained by indirect measurement For comparison, if ,in If the torque difference threshold is reached, the torque detection will be stopped and maintenance will be prompted. The operation time of the wind turbine will be recorded after each maintenance. , the final torque value used ,in is always 1, and and By adjusting the weights, we can increase the adoption of direct testing in the early stages and switch to indirect testing in the later stages, maintaining the accuracy of testing and leveraging the advantages of different testing methods.

[0050] A method combining direct and indirect detection results is adopted. Direct detection results are used in a short period of time after maintenance is completed, and the weight ratio of indirect detection results is increased over a long period of time, thereby improving the accuracy of detection results throughout the entire time. When performing indirect measurement, a combination of eccentric wheels, butterfly springs, and Hall sensors is used to indirectly detect the wind actuation torque using the principle of torque balance. This detection method can reduce dependence on direct mechanical transmission, maintain a certain detection accuracy even when rotating parts continue to wear and loosen, and reduce maintenance costs.

[0051] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0052] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art will be able to modify the technical solutions described in the aforementioned embodiments or substitute equivalents for some of the technical features. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A wind turbine blade operating status detection system, characterized by: The invention comprises a main shaft (1) rotatably arranged on an external mounting seat, a torque sensor (8) being arranged at one end of the main shaft (1), an eccentric wheel (4) being movably sleeved on the outer wall of the main shaft (1) through a bearing, an annular guide rail (5) being arranged on the outside of the main shaft (1), the annular guide rail (5) being fixedly connected to the side wall of the mounting seat of the main shaft (1), a friction seat (6) being arranged on one side of the eccentric wheel (4), a pre-tightening block (61) being arranged at the bottom of the friction seat (6), the friction seat (6) being in contact with the outer wall of the eccentric wheel (4), a permanent magnet being arranged on the friction seat (6), a Hall sensor (62) being arranged on one side of the friction seat (6), a moving mechanism (73) being movably arranged on the annular guide rail (5), a moving seat (7) being fixedly arranged on the moving mechanism (73), and a rolling abutting component being arranged in the moving seat (7); The rolling support assembly includes a mounting block (75) movably connected to the inner wall of the movable seat (7) by a thread, a butterfly spring (74) and a distance sensor (76) are installed on the top of the mounting block (75), a roller bracket (72) is installed on the top of the butterfly spring (74), a roller (71) is rotatably mounted on the roller bracket (72), the roller (71) contacts the outer wall of the eccentric wheel (4), and the rotation center of the annular guide rail (5) and the main shaft (1) are in a straight line; One end of the main shaft (1) is provided with blades (2) distributed in a circumferential manner, and a pressure strain gauge (3) is provided between the blades (2) and the inner wall of the main shaft (1); It also includes a resultant force direction determination module, a rotation angle calculation module, an output voltage recording module, and a torque calculation module, wherein the resultant force direction determination module is electrically connected to the pressure strain gauge (3) through a control system, the rotation angle calculation module is electrically connected to the distance sensor (76) through a control system, the output voltage recording module is electrically connected to the Hall sensor (62) through a control system, and the torque calculation module is electrically connected to the output voltage recording module; The resultant force direction determination module is used to calculate the resultant force of the wind acting on the blade (2) according to the pressure detection results of each pressure strain gauge (3); the rotation angle calculation module is used to calculate the rotation angle of the eccentric wheel (4) according to the deformation of the butterfly spring; the output voltage recording module is used to count the output voltage of the Hall sensor (62) at different detection times; and the torque calculation module is used to detect the torque of the main shaft (1) according to the output voltage change of the Hall sensor (62); The system works as follows: S1. Before the wind turbine is put into use, a known vertical force is applied to a single blade (2), and the operational relationship between the output voltage of the Hall sensor (62) and the torque of the main shaft (1) is determined according to the state of the eccentric wheel (4); S2. When the wind turbine generator is maintained and in operation, a torque sensor (8) is used to record the main shaft (1) torque for direct detection, and a Hall sensor (62) is used to indirectly detect the main shaft torque; S3. Adjust the weights of the direct and indirect detection results based on the operating time. If the difference between the two results is too large, stop torque detection and prompt maintenance. After the next wind turbine maintenance is completed, reset the operating time and restart the adjustment. The specific steps of S1 are: S1-1. When the blade (2) is installed, no force is applied to the blade (2), so that the moving mechanism (73) drives the moving seat (7) to move to the lowest end of the annular guide rail (5). At this time, the butterfly spring (74) has an initial deformation because the roller (71) contacts the bottom of the eccentric wheel (4). Provide preload force for the eccentric wheel (4) so ​​that the elastic coefficient of the butterfly spring (74) is , the preload block (61) always applies a constant upward support force to the friction seat (6) , calculated based on the torque balance ,in For support Horizontal distance from the eccentric wheel (4), is the rotation center of the eccentric wheel (4) With the rotation center of the main shaft (1) distance; S1-2: At this time, one of the blades (2) is placed in a horizontal state, and a vertical downward force is applied to the blade (2) in the horizontal state. ,at this time can be transformed into a vertical downward force acting on the main axis (1) with a magnitude of Pressure and torque combination of, and ,in For the force The force application point of the blade (2) distance, and torque The butterfly spring (74) generates an upward supporting force on the eccentric wheel (4) due to the pressure. ,in is the deformation of the butterfly spring (74), so according to the torque balance ; S1-3, with The increase of will cause the friction seat (6) to move upward slightly until the preload block (61) is separated from the friction seat (6). , so that the eccentric wheel (4) rotates at this time compared to when it is stationary Angle, at this time ,because The permanent magnet moves with the rotation of the eccentric wheel (4), and the magnetic field it generates also moves around the Rotation , that is, the relative position change in the magnetic field is ,in The Hall sensor (62) and The horizontal distance, the output voltage change value of the Hall sensor (62) ,in is the relative position change conversion coefficient, so ; The specific steps of S2 are: S2-1. Each blade (2) rotates in a circular motion under the action of wind. The forces detected by the three pressure strain gauges (3) are 、 、 , we can get the combined force of the three , The size of the torque cannot be calculated, only considering direction, will Equivalent to S1 , but the direction is not vertically downward, but according to 、 、 The size of the three depends on the S2-2, in order to maintain the reaction force provided by the roller (71) to the eccentric wheel (4) On the same line, the driving mechanism (73) quickly moves the moving seat (7) to The torque of the spindle (1) is calculated again according to the steps in S1. ; S2-3, fixed time interval 、 、 The sizes of the three are counted and the Reselect the direction and then The position of the movable seat (7) is adjusted in the direction of the axis, and the torque of the main shaft (1) at different times is obtained at fixed intervals. .

2. The wind turbine blade operating status detection system according to claim 1, characterized in that: Specifically, the S3 is to directly obtain the current measured torque of the main shaft (1) through the torque sensor (8) , and the torque obtained by indirect measurement For comparison, if ,in If the torque difference threshold is reached, the torque detection will be stopped and maintenance will be prompted. The operation time of the wind turbine will be recorded after each maintenance. , the final torque value used ,in is always 1, and and Inversely proportional.

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