Fan blade rotating speed monitoring device based on optical fiber technology

Abstract

A fan blade rotating speed monitoring device based on the optical fiber technology comprises a reflecting mirror and a speed measuring optical fiber, one end of the speed measuring optical fiber is aligned with the top of the movement stroke of the reflecting mirror, the reflecting mirror is located on a fan blade, the other end of the speed measuring optical fiber is connected with an optical splitter, a photoelectric converter and a controller, and the speed measuring optical fiber is further connected with a laser transmitter. Firstly, a laser generator generates an incident light signal, the incident light signal is reflected into a reflected light signal every time a reflector rotates and aligns to a speed measurement optical fiber, and the reflected light signal is processed into rotating speed information; the speed measuring optical fiber has good magnetic field interference resistance, and the rotating speed is monitored accurately; and the monitoring is not influenced by factors such as illumination and wind power, so that the adaptability to the monitoring environment is better. Therefore, according to the design, the fan blade is accurately monitored, and the adaptability to the monitoring environment is good.

Description

Technical Field

[0001] The utility model relates to a fan blade monitoring device, belongs to the technical field of fan blade detection, and particularly relates to a fan blade rotation speed monitoring device based on optical fiber technology. Background Art

[0002] The global energy crisis is getting worse, and wind power generation plays an important role in the increasingly urgent energy transformation in today's world. Wind power is a clean energy that has almost no impact on the environment during the power generation process. Using wind power generation can reduce dependence on fossil fuels, reduce carbon emissions, and effectively respond to global warming. At the same time, the continuous advancement of wind power generation technology and the reduction of costs have made it increasingly competitive in the energy industry, providing huge opportunities for sustainable economic development.

[0003] In the field of wind power generation, wind turbine blades are a vital component of wind turbines, and they directly affect the capture and conversion efficiency of wind energy. Wind turbine blades in good structural condition can maximize the use of wind energy resources and improve power generation efficiency. Compared with other components, wind turbine blades are directly exposed to the air and rotate, so the structure of wind turbine blades is very easy to be damaged; when the surface of wind turbine blades is damaged, that is, the surface of the blades is no longer smooth, the surface resistance of the blades increases, which will have a serious impact on the process of wind turbines converting wind energy into kinetic energy, and will cause the working performance of the blades to decline, which is specifically manifested as a decrease in the rotation speed of the blades.

[0004] At present, electromagnetic sensors are often used to monitor the rotational speed of wind turbine blades. Although electromagnetic sensors have no mechanical structure and will not rust or corrode, they are very susceptible to interference from external magnetic fields, resulting in inaccurate rotational speed monitoring.

[0005] The information disclosed in this background technology section is only intended to increase the understanding of the overall background of the application, and should not be regarded as acknowledging or suggesting in any form that the information constitutes the prior art already known to ordinary technicians in this field. Summary of the invention

[0006] The purpose of the utility model is to overcome the defects and problems of inaccurate rotation speed monitoring of fan blades in the prior art, and to provide a fan blade rotation speed monitoring device based on optical fiber technology which can accurately monitor the rotation speed of fan blades.

[0007] To achieve the above objectives, the technical solution of the utility model is:

[0008] A fan blade speed monitoring device based on optical fiber technology, the device comprising a reflector and a speed measuring optical fiber;

[0009] The speed measuring optical fiber includes an incident end, a reflecting end and an output end. The middle of the output end and the top of the movement stroke of the reflector are located at the same height. The movement stroke of the reflector is to rotate with the rotation center of the fan blade as the center of the circle. One side of the reflector is connected to one end of the fan blade; the incident end is connected to the outlet end of the first laser transmitter, the reflecting end is connected to the splitting entrance end of the spectrometer, the splitting exit end of the spectrometer is connected to one end of the photoelectric converter, and the other end of the photoelectric converter is connected to one end of the controller.

[0010] A strain monitoring device is arranged in the shell of the wind turbine blade, and the strain monitoring device includes a sensing optical fiber, in which a plurality of Bragg gratings are evenly distributed, the sensing inlet end of the sensing optical fiber is connected to one end of the second laser transmitter, and the sensing outlet end of the sensing optical fiber is connected to one end of the optical time domain phase reflectometer.

[0011] The end of the fan blade close to the center of rotation is the proximal end, and a plurality of Bragg gratings are evenly distributed on the proximal end; the end of the fan blade away from the center of rotation is the distal end, and a plurality of Bragg gratings are evenly distributed on the distal end.

[0012] Two Bragg gratings are evenly distributed on one end of the proximal end close to the center of rotation, and four Bragg gratings are evenly distributed on one end of the proximal end far from the center of rotation;

[0013] Four Bragg gratings are evenly distributed on one end of the distal end close to the center of rotation, and two Bragg gratings are evenly distributed on one end of the distal end away from the center of rotation.

[0014] One end of the second laser transmitter is connected to one end of the optical fiber coupler, and the other end of the optical fiber coupler is connected to the sensing input end.

[0015] The number of the light splitting outlet ports is two, and each light splitting outlet port is connected to a photoelectric converter.

[0016] The number of the reflectors is one to three, and each reflector is connected to a side of a fan blade close to the emission end.

[0017] The outlet end of the first laser transmitter is connected to one end of a multimode optical fiber coupler, and the other end of the multimode optical fiber coupler is connected to the incident end.

[0018] The outer cover of the emission end is provided with a protective cover; the protective cover comprises a horizontal tube and a vertical tube, one end of the vertical tube is vertically connected to one end of the horizontal tube, and the other end of the horizontal tube faces the top of the movement stroke of the reflector.

[0019] One end of the reflector away from the emission end is connected to one side of the epoxy resin adhesive, and the other side of the epoxy resin adhesive is connected to one side of the fan blade.

[0020] Compared with the prior art, the beneficial effects of the utility model are:

[0021] 1. In a fan blade speed monitoring device based on optical fiber technology, the utility model includes a reflector and a speed measuring optical fiber. The output end of the speed measuring optical fiber is aligned with the top of the movement stroke of the reflector. The reflector is located on the fan blade. The incident end of the speed measuring optical fiber is connected to the first laser transmitter. The reflecting end of the speed measuring optical fiber is connected to the optical splitter, the photoelectric converter, and the controller in sequence. When used, the first incident light signal is first emitted by the first laser transmitter, and the first incident light signal is then emitted after passing through the incident end and the output end. At the same time, the fan blade rotates to drive the reflector to rotate. When the reflector rotates to align with the output end, the reflector reflects the first incident light signal and then obtains a first reflected light signal. The first reflected light signal then passes through the output end and the reflecting end in sequence. Then, the first reflected light signal is processed by the optical splitter and the photoelectric converter in sequence to obtain an electrical signal in the form of a pulse. The electrical signal is then processed by the controller to obtain the speed information of the fan blade. The utility model also has the following advantages:

[0022] First point: Every time the reflector rotates to align with the emission end, a first reflected light signal can be obtained, so the speed information of the fan blade can be obtained by combining the interval time between the first reflected light signal and the second reflected light signal; the speed measuring optical fiber has good resistance to magnetic field interference, is not affected by external interference, and has good insulation, so the speed monitoring of the fan blade is accurate;

[0023] Second point: The speed measurement optical fiber is a multimode optical fiber, which is suitable for short-time transmission; and the multimode optical fiber has strong adaptability to the harsh environment of the wind farm and is not affected by light intensity, wind intensity and measurement distance;

[0024] Therefore, the utility model can monitor the rotation speed of the fan blades accurately and adapt well to the monitoring environment.

[0025] 2. In the utility model, a fan blade speed monitoring device based on optical fiber technology is provided in the housing on each fan blade. A sensing optical fiber is provided in the sensing optical fiber. The sensing optical fiber is connected to a second laser transmitter and an optical time domain phase reflectometer. When in use, the second laser transmitter sends a second incident light signal to the sensing optical fiber. The second incident light signal enters the Bragg grating, and then the Bragg grating obtains a second reflected light signal. The second reflected light signal is processed by the optical time domain phase reflectometer. The stress and strain information of the fan blade is obtained by the central wavelength offset of the second reflected light signal, and the damaged part information of the fan blade can be obtained, so as to achieve the effect of monitoring the state of the fan blade surface. The sensing optical fiber is shallowly buried in the surface layer of the fan blade, and the outside of the sensing optical fiber is also wrapped with GFPR material (fan blade manufacturing material). Therefore, the utility model can monitor the state of the fan blade surface.

[0026] 3. In the utility model, a wind turbine blade speed monitoring device based on optical fiber technology, the number of the splitter outlet ends is two; the number of the reflectors is three, and the first laser transmitter is connected to the incident end through a multimode optical fiber coupler. When used, the speed measuring optical fiber is a multimode optical fiber, so it cooperates with the multimode optical fiber coupler to accommodate multiple incident light signals; the number of the reflectors is three, so when the wind turbine blade rotates one circle, three first reflected light signals can be obtained, and more first reflected light signals help to improve the accuracy of speed monitoring; the number of the splitter outlet ends is two, that is, the first reflected light signal can be divided into two first reflected light signals, one first reflected light signal is used for detection, and the other first reflected light signal is used for auxiliary detection to improve the monitoring accuracy. Therefore, the wind speed monitoring accuracy of the utility model is relatively high.

[0027] 4. In the fan blade speed monitoring device based on optical fiber technology of the utility model, the outer cover of the output end is provided with a protective cover, and the reflector is connected to the fan blade through an epoxy resin adhesive. When used, the protective cover is used to fix the output end so that the output end can stably emit the first incident light signal; the epoxy resin adhesive stably bonds the reflector and the fan blade to prevent the reflector from falling, so that the reflector can stably reflect the first reflected light signal. Therefore, the structure of the present invention is stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a structural schematic diagram of the utility model.

[0029] Figure 2 yes Figure 1 Schematic diagram of the structure of the medium speed monitoring device.

[0030] Figure 3 yes Figure 2 Schematic diagram of the structure of the middle reflection end.

[0031] Figure 4 yes Figure 1 Schematic diagram of the structure of the middle shell.

[0032] Figure 5 yes Figure 4 Schematic diagram of the structure of the medium strain monitoring device.

[0033] Figure 6 yes Figure 5 Schematic diagram of the structure of the optical fiber used in the test.

[0034] Figure 7 yes Figure 1 Schematic diagram of the structure of the medium strain monitoring device.

[0035] Figure 8 yes Figure 7 Schematic diagram of the structure of the medium speed measurement optical fiber.

[0036] Fig. 9 yes Figure 8 Schematic diagram of the structure of the optical splitter.

[0037] Fig.10 yes Figure 7 Schematic diagram of the structure of the second laser emitter.

[0038] In the figure: rotation speed monitoring device 1, reflector 11, epoxy resin adhesive 111, speed measuring optical fiber 12, incident end 121, reflecting end 122, output end 123, protective cover 124, horizontal tube 125, vertical tube 126, first laser emitter 13, spectrometer 14, spectrometer entrance end 141, spectrometer exit end 142, photoelectric converter 15, controller 16, strain monitoring device 2, measuring optical fiber 21, Bragg grating 211, measuring entrance end 212, measuring exit end 213, second laser emitter 22, optical time domain phase reflectometer 23, fan blade 3, shell 31, fan chassis 32, proximal end 33, distal end 34, rotation center 35, multimode optical fiber coupler 4, optical fiber coupler 5. DETAILED DESCRIPTION

[0039] The present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0040] See also Figure 1 — Fig.10 , a wind turbine blade speed monitoring device based on optical fiber technology, the device comprising a reflector 11 and a speed measuring optical fiber 12;

[0041] The speed measuring optical fiber 12 includes an incident end 121, a reflecting end 122 and an output end 123. The middle of the output end 123 is located at the same height as the top of the movement stroke of the reflector 11. The movement stroke of the reflector 11 rotates around the rotation center of the fan blade 3. One side of the reflector 11 is connected to one end of the fan blade 3. The incident end 121 is connected to the outlet end of the first laser emitter 13, the reflecting end 122 is connected to the splitting entrance end 141 of the splitter 14, the splitting exit end 142 of the splitter 14 is connected to one end of the photoelectric converter 15, and the other end of the photoelectric converter 15 is connected to one end of the controller 16.

[0042] A strain monitoring device 2 is provided in the shell 31 of the wind turbine blade 3, and the strain monitoring device 2 includes a sensing optical fiber 21, in which a plurality of Bragg gratings 211 are evenly distributed, a sensing input end 212 of the sensing optical fiber 21 is connected to one end of a second laser emitter 22, and a sensing output end 213 of the sensing optical fiber 21 is connected to one end of an optical time domain phase reflectometer 23.

[0043] The end of the fan blade 3 close to the rotation center 35 is the proximal end 33, and a plurality of Bragg gratings 211 are evenly distributed on the proximal end 33; the end of the fan blade 3 away from the rotation center 35 is the distal end 34, and a plurality of Bragg gratings 211 are evenly distributed on the distal end 34.

[0044] Two Bragg gratings 211 are evenly distributed on one end of the proximal end 33 close to the rotation center 35, and four Bragg gratings 211 are evenly distributed on one end of the proximal end 33 away from the rotation center 35;

[0045] Four Bragg gratings 211 are evenly distributed on one end of the distal end 34 close to the rotation center 35 , and two Bragg gratings 211 are evenly distributed on one end of the distal end 34 away from the rotation center 35 .

[0046] One end of the second laser emitter 22 is connected to one end of the optical fiber coupler 5 , and the other end of the optical fiber coupler 5 is connected to the sensing input end 212 .

[0047] There are two light splitting outlet ports 142 , and each light splitting outlet port 142 is connected to a photoelectric converter 15 .

[0048] The number of the reflectors 11 is one to three, and each reflector 11 is connected to a surface of a fan blade 3 close to the emission end 123 .

[0049] The outlet end of the first laser emitter 13 is connected to one end of the multimode fiber coupler 4 , and the other end of the multimode fiber coupler 4 is connected to the incident end 121 .

[0050] The outer cover of the emission end 123 is provided with a protective cover 124 ; the protective cover 124 includes a horizontal tube 125 and a vertical tube 126 , one end of the vertical tube 126 is vertically connected to one end of the horizontal tube 125 , and the other end of the horizontal tube 125 faces the top of the movement stroke of the reflector 11 .

[0051] One end of the reflector 11 away from the emission end 123 is connected to one side of the epoxy resin adhesive 111 , and the other side of the epoxy resin adhesive 111 is connected to one side of the fan blade 3 .

[0052] The supplementary description of this utility model is as follows:

[0053] The controller 16 described in the utility model is: an information processing device; when the controller 16 receives an electrical signal in a pulse form, the controller 16 performs an amplification and shaping technology on it, and the controller 16 then processes it into a rotation speed value; when the controller 16 receives an electrical signal containing damage information, the controller 16 processes it into information on the damaged part of the fan blade 3.

[0054] Embodiment 1:

[0055] See also Figure 1 — Fig.10 , a wind turbine blade speed monitoring device based on optical fiber technology, characterized in that: the device includes a reflector 11 and a speed measuring optical fiber 12; the speed measuring optical fiber 12 includes an incident end 121, a reflecting end 122 and an emitting end 123, the middle of the emitting end 123 is located at the same height as the top of the movement stroke of the reflector 11, the movement stroke of the reflector 11 is to rotate with the rotation center of the wind turbine blade 3 as the center of the circle, and one side of the reflector 11 is connected to one end of the wind turbine blade 3; the incident end 121 is connected to the outlet end of the first laser emitter 13, the reflecting end 122 is connected to the splitting entrance end 141 of the splitter 14, the splitting exit end 142 of the splitter 14 is connected to one end of the photoelectric converter 15, and the other end of the photoelectric converter 15 is connected to one end of the controller 16.

[0056] When in use, the first laser emitter 13 first emits a first incident light signal, the first incident light signal passes through the incident end 121, and then passes through the exit end 123. At this time, the fan blade 3 is also rotating continuously, so the reflector 11 is also rotating continuously. Whenever the reflector 11 rotates to align with the exit end 123, the first incident light signal is reflected by the reflector 11 to obtain a first reflected light signal, the first reflected light signal passes through the exit end 123, and then passes through the reflection end 122. The first reflected light signal passes through the splitter entrance end 141 and the splitter exit end 142 in sequence, and then the first reflected light signal enters the photoelectric converter 15 and is processed into an electrical signal in the form of a pulse, and the electrical signal enters the controller 16 and is processed into the rotation speed information of the fan blade 3.

[0057] Embodiment 2:

[0058] The basic content is the same as that of Example 1, except that:

[0059] See also Figure 1 — Figure 8 The housing 31 of the fan blade 3 is provided with a strain monitoring device 2, and the strain monitoring device 2 includes a sensing optical fiber 21, and a plurality of Bragg gratings 211 are evenly distributed in the sensing optical fiber 21. The sensing inlet end 212 of the sensing optical fiber 21 is connected to one end of the second laser emitter 22, and the sensing outlet end 213 of the sensing optical fiber 21 is connected to one end of the optical time domain phase reflectometer 23. The end of the fan blade 3 close to the rotation center 35 is the proximal end 33, and a plurality of Bragg gratings 211 are evenly distributed on the proximal end 33; the end of the fan blade 3 away from the rotation center 35 is the distal end 34, and a plurality of Bragg gratings 211 are evenly distributed on the distal end 34. Two Bragg gratings 211 are evenly distributed on the end of the proximal end 33 close to the rotation center 35, and four Bragg gratings 211 are evenly distributed on the end of the proximal end 33 away from the rotation center 35; four Bragg gratings 211 are evenly distributed on the end of the distal end 34 close to the rotation center 35, and two Bragg gratings 211 are evenly distributed on the end of the distal end 34 away from the rotation center 35. One end of the second laser emitter 22 is connected to one end of the optical fiber coupler 5, and the other end of the optical fiber coupler 5 is connected to the sensing input port 212.

[0060] When used, the second laser emitter 22 first emits a second incident light signal, and the second incident light signal then enters the optical fiber coupler 5 and is converted into multiple second incident light signals, and then the multiple second incident light signals enter the sensing input port 212, and the second incident light signal generates a second reflected light signal on the Bragg grating 211; if a certain part of the fan blade 3 is damaged, the Bragg grating 211 in the part will be deformed, thereby causing the center wavelength of the second reflected light signal generated on the Bragg grating 211 to shift; the second reflected light signal then passes through the sensing output port 213, and then the second reflected light signal enters the optical time domain phase reflectometer 23 and is processed as damage information of the fan blade 3; the damaged part The greater the deformation, the greater the central wavelength offset; two rows of Bragg gratings 211 are arranged at the near end 33 and the far end 34 respectively, four Bragg gratings 211 are arranged at the wider part of the near end 33, and two Bragg gratings 211 are arranged at the narrower part of the near end 33, four Bragg gratings 211 are arranged at the wider part of the far end 34, and two Bragg gratings 211 are arranged at the narrower part of the far end 34, thereby realizing comprehensive monitoring of the wind turbine blades 3; the number of Bragg gratings 211 or the position of the Bragg gratings 211 can be increased or decreased or the position of the Bragg gratings 211 can be changed as needed to achieve better monitoring effect; the sensing optical fiber 21 is a multimode optical fiber, so the optical fiber coupler 5 is used to cooperate to obtain multiple beams of second incident laser signals.

[0061] Embodiment 3:

[0062] The basic content is the same as that of Example 1, except that:

[0063] See also Figure 1 — Fig.10 The number of the light splitting outlet ports 142 is two, and each light splitting outlet port 142 is connected to a photoelectric converter 15. The number of the reflectors 11 is one to three, and each reflector 11 is respectively connected to a side of a fan blade 3 close to the exit end 123. The exit end of the first laser emitter 13 is connected to one end of the multimode fiber coupler 4, and the other end of the multimode fiber coupler 4 is connected to the incident end 121.

[0064] When in use, the first laser emitter 13 emits a first incident light signal, and the first incident light signal then enters the multimode fiber coupler 4. At this time, the first incident light signal is divided into multiple identical first incident light signals, and then multiple identical first incident light signals enter the incident end 121. The fiber coupler 5 cooperates with the sensing fiber 21 belonging to the multimode fiber, which can effectively reduce the device cost compared to the use of single-mode fiber. The three fan blades 3 are all in a rotating state. If the three fan blades 3 are provided with a reflector 11, the reflector 11 reflects the first incident light. The number of optical signals is large, so a large number of first reflected light signals can be obtained, which can improve the accuracy of the rotational speed information obtained by subsequent processing; after the first reflected light signal is divided into two identical first reflected light signals by the spectrometer 14, each first reflected light signal moves to a spectrometer outlet end 142 respectively, and each first reflected light signal is then moved to the photoelectric converter 15 respectively, and then each first reflected light signal moves to the controller 16, one first reflected light signal is used for detection, and the other first reflected light signal is used to assist and compare the detection of the first reflected light signal.

[0065] Embodiment 4:

[0066] The basic content is the same as that of Example 1, except that:

[0067] See also Figure 1 — Fig.10 The outer cover of the emission end 123 is provided with a protective cover 124; the protective cover 124 includes a horizontal tube 125 and a vertical tube 126, one end of the vertical tube 126 is vertically connected to one end of the horizontal tube 125, and the other end of the horizontal tube 125 faces the top of the movement stroke of the reflector 11. One end of the reflector 11 away from the emission end 123 is connected to one side of the epoxy resin adhesive 111, and the other side of the epoxy resin adhesive 111 is connected to one side of the fan blade 3.

[0068] When in use, a protective cover 124 is provided on the outside of the output end 123 to fix and protect the output end 124, so that the first incident light signal emitted by the output end 123 is stable, thereby obtaining a stable first reflected light signal; the epoxy resin adhesive 111 is very suitable for bonding the fiberglass material of the fan blade 3 and the glass material of the reflector 11, and the epoxy resin adhesive 111 has good viscosity, and only a small amount of epoxy resin adhesive 111 is needed to firmly adhere the reflector 11 to the fan blade 3. The epoxy resin adhesive 111 is stable in nature when used, and also has the advantages of being wind and rain resistant and high temperature resistant.

[0069] The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiment. Any equivalent modifications or changes made by ordinary technicians in this field based on the contents disclosed in the present invention should be included in the protection scope recorded in the claims.

Claims

1. A fan blade speed monitoring device based on optical fiber technology, characterized in that: The device comprises a reflector (11) and a speed measuring optical fiber (12); The speed measuring optical fiber (12) comprises an incident end (121), a reflection end (122) and an output end (123); the middle of the output end (123) is located at the same height as the top of the movement stroke of the reflector (11); the movement stroke of the reflector (11) is to rotate with the rotation center of the fan blade (3) as the center of the circle; one surface of the reflector (11) is connected to one end of the fan blade (3); the incident end (121) is connected to the output end of the first laser emitter (13); the reflection end (122) is connected to the light splitting entrance end (141) of the light splitter (14); the light splitting exit end (142) of the light splitter (14) is connected to one end of a photoelectric converter (15); and the other end of the photoelectric converter (15) is connected to one end of a controller (16).

2. The fan blade speed monitoring device based on optical fiber technology according to claim 1 is characterized in that: A strain monitoring device (2) is arranged in the shell (31) of the fan blade (3), and the strain monitoring device (2) comprises a sensing optical fiber (21), a plurality of Bragg gratings (211) are evenly distributed in the sensing optical fiber (21), a sensing input end (212) of the sensing optical fiber (21) is connected to one end of a second laser transmitter (22), and a sensing output end (213) of the sensing optical fiber (21) is connected to one end of an optical time domain phase reflectometer (23).

3. The fan blade speed monitoring device based on optical fiber technology according to claim 2 is characterized in that: The end of the fan blade (3) close to the rotation center (35) is a proximal end (33), and a plurality of Bragg gratings (211) are evenly distributed on the proximal end (33); the end of the fan blade (3) away from the rotation center (35) is a distal end (34), and a plurality of Bragg gratings (211) are evenly distributed on the distal end (34).

4. The fan blade speed monitoring device based on optical fiber technology according to claim 3 is characterized in that: Two Bragg gratings (211) are evenly distributed on one end of the proximal end (33) close to the rotation center (35), and four Bragg gratings (211) are evenly distributed on one end of the proximal end (33) away from the rotation center (35); Four Bragg gratings (211) are evenly distributed on an end of the distal end (34) close to the rotation center (35), and two Bragg gratings (211) are evenly distributed on an end of the distal end (34) away from the rotation center (35).

5. The fan blade speed monitoring device based on optical fiber technology according to claim 4 is characterized in that: One end of the second laser emitter (22) is connected to one end of the optical fiber coupler (5), and the other end of the optical fiber coupler (5) is connected to the sensing input end (212).

6. The fan blade speed monitoring device based on optical fiber technology according to claim 1 is characterized in that: The number of the light splitting outlet ports (142) is two, and each light splitting outlet port (142) is connected to a photoelectric converter (15).

7. The fan blade speed monitoring device based on optical fiber technology according to claim 6 is characterized in that: The number of the reflectors (11) is one to three, and each reflector (11) is respectively connected to a surface of a fan blade (3) close to the emission end (123).

8. The fan blade speed monitoring device based on optical fiber technology according to claim 7 is characterized in that: The outlet end of the first laser emitter (13) is connected to one end of the multimode optical fiber coupler (4), and the other end of the multimode optical fiber coupler (4) is connected to the incident end (121).

9. The wind turbine blade speed monitoring device based on optical fiber technology according to claim 1, characterized in that: The exterior of the emission end (123) is covered with a protective cover (124); the protective cover (124) comprises a horizontal tube (125) and a vertical tube (126); one end of the vertical tube (126) is vertically connected to one end of the horizontal tube (125); and the other end of the horizontal tube (125) faces the top of the movement stroke of the reflector (11).

10. The wind turbine blade speed monitoring device based on optical fiber technology according to claim 1, characterized in that: One end of the reflector (11) away from the emission end (123) is connected to one side of the epoxy resin adhesive (111), and the other side of the epoxy resin adhesive (111) is connected to one side of the fan blade (3).

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