Vibration signal anti-noise monitoring system based on double-path optical fiber Michelson interference orthogonal detection

Abstract

The invention provides a vibration signal anti-noise monitoring system based on double-path optical fiber Michelson interference orthogonal detection, and belongs to the technical field of vibration signal anti-noise monitoring. In order to solve the technical problems that an existing anti-noise vibration monitoring system is high in light source cost, poor in anti-noise effect and incapable of comprehensively capturing multi-dimensional acoustic vibration characteristics of equipment, the adopted technical scheme is that the output end of a laser pumping source is connected with the input end a of a wavelength division multiplexer, and the input end b of the wavelength division multiplexer is connected with the output end of a first fiber grating array; the input end of the first fiber grating array is connected with the output end of the polarization controller; an output end c of the wavelength division multiplexer is connected with an input end of a first erbium-doped fiber, an output end of the first erbium-doped fiber is connected with a port a of a first optical circulator, a port b of the first optical circulator is connected with an input end of a second fiber bragg grating array, and a port c of the first optical circulator is connected with an input end a of a first 1 * 2 coupler; the method is applied to vibration signal anti-noise monitoring.

Description

Technical Field

[0001] This invention provides a vibration signal noise reduction monitoring system based on dual-path fiber Michelson interferometric orthogonal detection, belonging to the field of vibration signal noise reduction monitoring technology. Background Technology

[0002] In the field of industrial automation and equipment health monitoring, continuously monitoring changes in the acoustic and vibration signals of equipment is an important means of assessing equipment operating status and achieving predictive maintenance. The sound waves and vibration signals generated by equipment during operation contain rich status information, and abnormal changes are often early signs of equipment performance degradation or potential failures. Timely capture and analysis of these anomalies are of vital economic and safety significance for preventing unplanned downtime, ensuring production safety, and extending equipment life.

[0003] However, the main electronic sensors used for vibration and acoustic monitoring are piezoelectric accelerometers, microphones, or eddy current sensors. These sensors have significant limitations in practical industrial applications. They are often susceptible to strong electromagnetic interference, temperature fluctuations, and complex background noise, which can lead to a decrease in signal-to-noise ratio and make it difficult to guarantee monitoring accuracy. In addition, the applicability of electronic sensors is also limited in certain flammable, explosive, or high-pressure special industrial environments.

[0004] With the development of fiber optic technology, fiber optic sensors, due to their advantages such as light weight, compact structure, high sensitivity, and resistance to electromagnetic interference, are increasingly being used in fields such as structural health monitoring and perimeter security. Among these, fiber optic vibration sensing systems based on Michelson interferometry offer advantages such as high sensitivity, low noise, and simple structure, making them suitable for monitoring vibration or acoustic signals. However, traditional Michelson interferometer structures still face the following three problems in practical applications: First, the system relies on expensive narrow-linewidth lasers to achieve interferometry, which is costly and sensitive to environmental disturbances, thus introducing noise limitations on the monitoring signal-to-noise ratio. Second, traditional interferometric structures cannot effectively distinguish between the real signal originating from the target being measured and the ubiquitous environmental common-mode noise (such as ground vibration, airborne sound waves, etc.), and the effective signal is easily submerged in complex industrial backgrounds with low signal-to-noise ratios. Finally, conventional probes are usually only sensitive to vibrations in a single direction, making it difficult to comprehensively capture the multi-dimensional acoustic and vibration characteristics of the equipment, thus limiting the accuracy of condition identification and diagnosis. In summary, it is necessary to improve upon the existing interference structure and develop a novel noise-resistant vibration monitoring system with high sensitivity. This system should incorporate a differential sensing mechanism that effectively suppresses environmental noise. The system should utilize a low-cost, low-noise, and stable light source, and the sensing probes should be able to detect vibrations in multiple directions and be flexibly optimized for placement based on the object being measured. This will enable accurate monitoring of vibration or acoustic signals, and provide early warnings and reports of abnormal conditions. By systematically addressing the issues of light source, noise reduction, and sensing structure, this system is of great significance for improving the safety and reliability of the entire production line. Summary of the Invention

[0005] To address the technical problems existing in the background art, the present invention adopts the following technical solution: providing a vibration signal noise reduction monitoring system based on dual-path fiber Michelson interferometric orthogonal detection, including a laser pump source, the output end of the laser pump source being connected to the a input end of a wavelength division multiplexer, the b input end of the wavelength division multiplexer being connected to the output end of a first fiber grating array, and the input end of the first fiber grating array being connected to the output end of a polarization controller; The output terminal c of the wavelength division multiplexer is connected to the input terminal of the first erbium-doped fiber, the output terminal of the first erbium-doped fiber is connected to the a port of the first optical circulator, the b port of the first optical circulator is connected to the input terminal of the second fiber grating array, and the c port of the first optical circulator is connected to the a input terminal of the first 1*2 coupler. The b output terminal of the first 1*2 coupler is connected to the a input terminal of the phase modulator, and the c output terminal of the first 1*2 coupler is connected to the input terminal of the polarization controller. The b output terminal of the phase modulator is connected to the input terminal of the second erbium-doped fiber, and the c input terminal of the phase modulator is connected to the c output terminal of the microprocessor. The output end of the second erbium-doped fiber is connected to the input end of the optical isolator, and the output end of the optical isolator is connected to the input end a of the 1*3 coupler; The b output terminal of the 1*3 coupler is connected to the input terminal of the second photodetector, the c output terminal of the 1*3 coupler is connected to the a port of the third optical circulator, and the d output terminal of the 1*3 coupler is connected to the a port of the second optical circulator. The b port of the second optical circulator is connected to the a input terminal of the second 1*2 coupler, and the c port of the second optical circulator is connected to the input terminal of the third photodetector. The b port of the third optical circulator is connected to the a input port of the third 1*2 coupler, and the c port of the third optical circulator is connected to the input port of the first photodetector. The output end b of the second 1*2 coupler is connected to the input end of the first sensing fiber, and the output end of the first sensing fiber is connected to the input end of the first Faraday rotating mirror. The output terminal of the second 1*2 coupler is connected to the input terminal of the second sensing fiber, and the output terminal of the second sensing fiber is connected to the input terminal of the second Faraday rotating mirror. The output end b of the third 1*2 coupler is connected to the input end of the third sensing fiber, and the output end of the third sensing fiber is connected to the input end of the third Faraday rotating mirror. The output terminal of the third 1*2 coupler is connected to the input terminal of the fourth sensing fiber, and the output terminal of the fourth sensing fiber is connected to the input terminal of the fourth Faraday rotating mirror. The output terminal of the first photodetector is connected to the input terminal of the first transimpedance amplifier module, and the output terminal of the first transimpedance amplifier module is connected to the b input terminal of the first proportional operation module. The output terminal of the second photodetector is connected to the input terminal a of the second transimpedance amplifier module, the output terminal b of the second transimpedance amplifier module is connected to the input terminal c of the first proportional operation module, and the output terminal c of the second transimpedance amplifier module is connected to the input terminal b of the second proportional operation module. The output terminal of the third photodetector is connected to the input terminal of the third transimpedance amplifier module, and the output terminal of the third transimpedance amplifier is connected to the c input terminal of the second proportional operation module. The output terminal 'a' of the first proportional operation module is connected to the input terminal of the first filtering module, the output terminal of the first filtering module is connected to the input terminal of the first demodulation module, and the output terminal of the first demodulation module is connected to the input terminal 'b' of the differential operation module. The output terminal 'a' of the second proportional operation module is connected to the input terminal of the second filtering module, the output terminal of the second filtering module is connected to the input terminal of the second demodulation module, and the output terminal of the second demodulation module is connected to the input terminal 'c' of the differential operation module. The output terminal a of the differential operation module is connected to the input terminal of the A / D conversion module, the output terminal of the A / D conversion module is connected to the input terminal b of the microprocessor, and the output terminal a of the microprocessor is connected to the input terminal of the wireless WiFi module. The wireless Wi-Fi module is wirelessly connected to the backend of the cloud server via a wireless network. The communication port of the cloud server backend is connected to the client.

[0006] The first sensing fiber, the second sensing fiber, the first Faraday rotator, and the second Faraday rotator are all encapsulated inside the first sensing probe; The third sensing fiber, the fourth sensing fiber, the third Faraday rotator, and the fourth Faraday rotator are all encapsulated inside the second sensing probe.

[0007] The cloud server backend performs spectrum analysis and pattern recognition on the vibration data, and sends the vibration data and alarm information to the client, providing the client with the device's operating status and alarm information.

[0008] The beneficial effects of this invention compared to the prior art are as follows: The vibration signal noise reduction monitoring system based on dual-path fiber Michelson interferometric orthogonal detection provided by this invention uses two fiber grating arrays as reflection and transmission filters in its light source part to filter the optical signal of the fiber ring laser, and amplifies the light source through erbium-doped fiber, so that the narrow linewidth laser has the advantages of low cost, low noise, and stable power, suppresses the influence of light source noise on the vibration signal of the equipment, and improves the signal-to-noise ratio of the system; This invention constructs a dual-path Michelson interferometer structure. The light from the laser source is used as the reference light and the light signal returned by the fiber optic probe is proportionally canceled out. After amplification and filtering, the signal enters the phase demodulation circuit for demodulation. After demodulation, the two signals enter the differential circuit for differential division and further amplification. Environmental noise interference is filtered out, which can realize the accurate perception of vibration fault signals during equipment operation. This invention introduces an orthogonal detection mechanism into the design of a fiber optic sensing probe. By winding two sensing fibers in a specific manner around mutually orthogonal elastic elements, a single probe can simultaneously respond to vibration components in orthogonal spatial directions. This structural design not only improves probe sensitivity but also acquires directional vibration information, achieving vibration vector perception. It overcomes the shortcomings of traditional point-type or unidirectional sensors with limited information dimensions, providing richer feature data for accurate identification of equipment status. In actual deployment, the two probes are placed in different directions at key vibration points of the equipment to monitor vibration signals in orthogonal directions during equipment operation, improving the diagnostic rate of abnormal conditions in the target equipment and ensuring its normal operation. Attached Figure Description

[0009] The present invention will be further described below with reference to the accompanying drawings: Figure 1 This is a schematic diagram of the monitoring system of the present invention; Figure 2 This is a schematic diagram of the structure of the first sensing probe of the present invention; The numbers in the diagram represent the following: 1. Laser pump source; 2. First fiber grating array; 3. Wavelength division multiplexer; 4. First erbium-doped fiber; 5. First optical circulator; 6. First 1x2 coupler; 7. Second fiber grating array; 8. Polarization controller; 9. Phase modulator; 10. Second erbium-doped fiber; 11. Optical isolator; 12. 1x3 coupler; 13. Second optical circulator; 14. Third optical circulator; 15. Second 1x2 coupler; 16. First sensing fiber; 17. Second sensing fiber; 18. First Faraday rotator mirror; 19. Second Faraday rotator mirror; 20. First sensing probe; 21. Third 1x2 coupler; 22. Third sensing fiber; 23. 24. Fourth sensing fiber; 25. Third Faraday rotator mirror; 26. Fourth Faraday rotator mirror; 27. Second sensing probe; 28. First photodetector; 29. ​​Second photodetector; 30. Third photodetector; 31. First transimpedance amplifier module; 32. Second transimpedance amplifier module; 33. Third transimpedance amplifier module; 34. First proportional operation module; 35. Second proportional operation module; 36. First filtering module; 37. Second filtering module; 38. First demodulation module; 39. Second demodulation module; 40. Differential operation module; 41. A / D conversion module; 42. Microprocessor; 43. Wireless Wi-Fi module; 44. Cloud server backend; 45. Client. Detailed Implementation

[0010] like Figure 1 and Figure 2 As shown, the vibration signal noise-resistant monitoring system based on dual-path fiber Michelson interferometry orthogonal detection provided by this invention utilizes a fiber ring laser structure. The optical signal emitted from the laser pump source is filtered by two fiber grating arrays to form a low-cost, low-noise, and power-stable 1550nm narrow-linewidth laser as the system's light source, effectively suppressing the influence of light source noise on the vibration signal and improving the system's signal-to-noise ratio. This invention constructs a dual-path Michelson interferometry structure, performs proportional cancellation and demodulation on the signals acquired by the two probes and the light source signal, and then performs differential calculations to further amplify the signal while filtering out environmental noise interference, thus improving the system's signal-to-noise ratio. This invention improves the accuracy of identifying abnormal vibration states of equipment. It employs an orthogonal detection design for the fiber optic sensing probe, with the sensing fibers wound around mutually orthogonal elastic cylindrical arms. This enhances probe sensitivity and allows for simultaneous sensing of vibration components in orthogonal spatial directions, enabling the measurement of vibration vector information. This significantly improves the accuracy and reliability of equipment status identification. By placing two probes in different directions at key vibration points of the equipment, it achieves the perception and measurement of multi-directional vibration vector information during equipment operation. In the event of a fault, vibration data and alarm information are sent to the user via a cloud server, enabling remote monitoring of the equipment's operating status.

[0011] Furthermore, such as Figure 1 The diagram shows the structure of the vibration signal noise reduction monitoring system of the present invention. The monitoring system includes a laser pump source 1, a first fiber grating array 2, a wavelength division multiplexer 3, a first erbium-doped fiber 4, a first optical circulator 5, a first 1x2 coupler 6, a second fiber grating array 7, a polarization controller 8, a phase modulator 9, a second erbium-doped fiber 10, an optical isolator 11, a 1x3 coupler 12, a second optical circulator 13, a third optical circulator 14, a second 1x2 coupler 15, a first sensing fiber 16, a second sensing fiber 17, a first Faraday rotator mirror 18, a second Faraday rotator mirror 19, a first sensing probe 20, a third 1x2 coupler 21, and a second 1x2 coupler 22. 22. Three-sensor fiber optic cable; 23. Fourth-sensor fiber optic cable; 24. Third Faraday rotator mirror; 25. Fourth Faraday rotator mirror; 26. Second sensor probe; 27. First photodetector; 28. Second photodetector; 29. ​​Third photodetector; 30. First transimpedance amplifier module; 31. Second transimpedance amplifier module; 32. Third transimpedance amplifier module; 33. First proportional operation module; 34. Second proportional operation module; 35. First filter module; 36. Second filter module; 37. First demodulation module; 38. Second demodulation module; 39. Differential operation module; 40. A / D conversion module; 41. Microprocessor; 42. Wireless Wi-Fi module; 43. Cloud server backend; 44. Client. Figure 2 The diagram shows the structure of the first and second sensing probes in the monitoring system. The sensing probes shown in the diagram have the first sensing fiber 16 and the second sensing fiber 17 wound around mutually orthogonal elastic cylindrical arms to sense vibration signals in the transverse and longitudinal directions, respectively. The internal structure of the second sensing probe 26 provided in this invention is consistent with that of the first sensing probe 20.

[0012] The following is combined with Figure 1 and Figure 2 Specific embodiments of the present invention are described below: In use, the laser emitted from the laser pump source 1 enters the wavelength division multiplexer 3 at input port a, which is coupled to the input port of the first erbium-doped fiber 4 for amplification before entering port a of the first optical circulator 5. The optical signal is output from port b of the first optical circulator 5 to the input port of the second fiber grating array 7. The second fiber grating array 7 acts as a mirror, filtering the optical signal for the first time and reflecting it. The reflected optical signal is output to port b of the first optical circulator 5, and then output from port c of the first optical circulator 5 to input port a of the first 1*2 coupler 6. Finally, it is output from port c of the first 1*2 coupler 6 to the polarization converter. The polarization controller 8 adjusts the polarization state of the optical signal and suppresses side modes before outputting it to the input of the first fiber grating array 2. The first fiber grating array 2 acts as a transmission mirror to filter the optical signal again before outputting it to the b input of the wavelength division multiplexer 3. Together with the optical signal from the laser pump source 1, it is coupled into the first erbium-doped fiber 4 to form a fiber ring 1550nm narrow linewidth laser. Compared with traditional narrow linewidth lasers, the narrow linewidth laser based on dual fiber grating arrays used in this invention has the characteristics of low cost, low noise, and stable power, and suppresses the influence of light source noise on the vibration signal of the equipment.

[0013] The b-output terminal of the first 1*2 coupler 6 outputs a narrow linewidth laser signal, which enters the a-input port of the phase modulator 9 for phase modulation. The b-output terminal of the phase modulator 9 is connected to the input terminal of the second erbium-doped fiber 10, which amplifies the optical signal again to ensure the stability of the laser power. The c-input terminal of the phase modulator 9 is connected to the c-output terminal of the microprocessor 41 to control the parameters of the phase modulation signal. The output end of the second erbium-doped fiber 10 is connected to the input end of the optical isolator 11, and the output end of the optical isolator 11 is connected to the a input end of the 1*3 coupler 12 to ensure unidirectional laser transmission. The b output end of the 1*3 coupler 12 is connected to the input end of the second photodetector 28 as a reference signal and is proportionally canceled with the two interference signals through the first proportional operation module 33 and the second proportional operation module 34 to avoid the influence of the accompanying amplitude modulation in the internally modulated laser signal on the demodulation result. The c output end of the 1*3 coupler 12 is connected to the a port of the third optical circulator 14, and the d output end of the 1*3 coupler 12 is connected to the a port of the second optical circulator 13.

[0014] The optical signal input at port a of the second optical circulator 13 is output to port a of the second 1*2 coupler 15 via port b of the second optical circulator 13. It is then split into two paths and output from ports b and c of the second 1*2 coupler 15 to the first sensing fiber 16 and the second sensing fiber 17, respectively. After reflection, the light reflected from the first Faraday rotator mirror 18 and the second Faraday rotator mirror 19 returns to ports b and c of the second 1*2 coupler 15 for coupling, forming the first Michelson interference structure. When an external vibration signal acts on the first sensing fiber 16 and the second sensing fiber 17, the two beams of light interfere at the second 1*2 coupler 15, realizing the sensing of the vibration signal. The interference signal is output from port a of the second 1*2 coupler 15 to port b of the second optical circulator 13, and then from port c of the second optical circulator 13 to the input of the third photodetector 29. The optical signal input at port a of the third optical circulator 14 is output through port b to port a of the third 1*2 coupler 21, then splits into two paths. These paths are output from ports b and c of the third 1*2 coupler 21 to the third sensing fiber 22 and the fourth sensing fiber 23, respectively, and then reflected at the input ends of the third Faraday rotator mirror 24 and the fourth Faraday rotator mirror 25. The light reflected from the third Faraday rotator mirror 24 and the fourth Faraday rotator mirror 25 returns to ports b and c of the third 1*2 coupler 21 for coupling, thus forming... A second Michelson interference structure is formed. When an external vibration signal acts on the third sensing fiber 22 and the fourth sensing fiber 23, the two beams of light interfere at the third 1*2 coupler 21, realizing the sensing of the vibration signal. The interference signal is output from port a of the third 1*2 coupler 21 to port b of the third optical circulator 14, and then from port c of the third optical circulator 14 to the input end of the first photodetector 27. Thus, a dual Michelson interference structure is formed, laying the optical path structure foundation for subsequent demodulation, differential processing, and other processing of the two interference signals. The first sensing probe 20 is used to encapsulate the first sensing fiber 16, the second sensing fiber 17, the first Faraday rotator 18, and the second Faraday rotator 19; The second sensing probe 26 is used to encapsulate the third sensing fiber 22, the fourth sensing fiber 23, the third Faraday rotator 24, and the fourth Faraday rotator 25; The first sensing probe 20 and the second sensing probe 26 mentioned above both adopt an orthogonal detection structure, which improves the sensitivity of the probe and can sense and demodulate vibration signal components in different directions. The first sensing probe 20 and the second sensing probe 26 are arranged in different directions at the key vibration parts of the equipment to monitor vibration signals in different directions during equipment operation.

[0015] The output terminal of the first photodetector 27 is connected to the input terminal of the first transimpedance amplifier module 30; the output terminal of the second photodetector 28 is connected to the input terminal a of the second transimpedance amplifier module 31; the output terminal of the third photodetector 29 is connected to the input terminal of the third transimpedance amplifier module 32; the first transimpedance amplifier module 30, the second transimpedance amplifier module 31, and the third transimpedance amplifier module 32 respectively perform I / V conversion and amplify the two interference signals and the laser signal; The a output terminal of the first proportional operation module 33 is connected to the input terminal of the first filtering module 35, the b input terminal of the first proportional operation module 33 is connected to the output terminal of the first transimpedance amplification module 30, and the c input terminal of the first proportional operation module 33 is connected to the b output terminal of the second transimpedance amplification module 31 to perform proportional cancellation operation on the first interference signal and the light source signal. The a output terminal of the second proportional operation module 34 is connected to the input terminal of the second filtering module 36, the b input terminal of the second proportional operation module 34 is connected to the c output terminal of the second transimpedance amplification module 31, and the c input terminal of the second proportional operation module 34 is connected to the output terminal of the third transimpedance amplification module 32, so as to perform proportional cancellation operation on the second interference signal and the light source signal. The output of the first filtering module 35 is connected to the input of the first demodulation module 37 to demodulate the first interference signal; the output of the second filtering module 36 is connected to the input of the second demodulation module 38 to demodulate the second interference signal.

[0016] The output terminal a of the differential operation module 39 is connected to the input terminal of the A / D conversion module 40, the input terminal b of the differential operation module 39 is connected to the output terminal of the first demodulation module 37, and the input terminal c of the differential operation module 39 is connected to the output terminal of the second demodulation module 38. The two demodulated vibration signals are differentially operated and amplified again to filter out the interference of environmental noise and further amplify the signal. Then the signal enters the A / D conversion module 40 for analog-to-digital conversion. The b input terminal of the microprocessor 41 is connected to the output terminal of the A / D conversion module 40, and the a output terminal of the microprocessor 41 is connected to the wireless WiFi module 42. The microprocessor 41 is used to receive data and control the frequency of analog-to-digital conversion. After further processing the collected vibration signal, the microprocessor 41 sends the data to the wireless WiFi module 42.

[0017] The wireless Wi-Fi module 42 connects to the cloud server backend 43 via a wireless network protocol, pushing vibration data to the database of the cloud server backend 43. The cloud server backend 43 connects to the client 44 via a network protocol. After performing spectrum analysis and feature extraction on the data in the database, the cloud server backend 43 identifies the working status of the device. When the device experiences abnormal vibration, the cloud server backend 43 sends vibration data and early warning information to the client 44 via a network interface protocol. Staff can then remotely monitor the working status of the device through the client 44, improving the stability of the device during operation and ensuring the normal operation of the system.

[0018] This invention addresses the monitoring of vibration signals generated during the operation of industrial equipment. It employs a dual-path Michelson interferometer structure, utilizing a dual fiber grating array to filter a fiber ring laser as the system's light source. A microprocessor-controlled phase modulator generates a modulation signal to internally modulate the laser source. The modulated signal is then split into three paths via a 1x3 coupler. One path serves as a reference path, while the other two paths pass through fiber optic probes within the Michelson interferometer structure. The two fiber optic probes are orthogonally designed, with their internal sensing fibers wound around mutually orthogonal elastic cylindrical arms. When subjected to external vibrations, the sensing fibers undergo deformation in both the lateral and longitudinal directions, enhancing the sensitivity of the probes and enabling the detection of orthogonal vibrations. The system senses the vibration vector signal. The optical signals returned by the two fiber optic probes are converted into photoelectric signals by an optical circulator. They are then proportionally canceled out by the reference optical path to remove the influence of accompanying amplitude modulation on the demodulation result. After amplification and filtering, the signals enter the demodulation circuit to demodulate the vibration signal. The two signals are differentially filtered to remove the influence of environmental noise, and then enter the A / D module for analog-to-digital conversion. The microprocessor further processes the data and sends it to the cloud server backend database via a wireless Wi-Fi module for spectrum analysis and feature recognition. When the equipment experiences abnormal vibration, an alarm is triggered, and the vibration data and alarm information are sent to the client to realize remote monitoring of the equipment's vibration status.

[0019] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A vibration signal noise-resistant monitoring system based on dual-path fiber Michelson interferometric orthogonal detection, comprising a laser pump source (1), characterized in that: The output end of the laser pump source (1) is connected to the a input end of the wavelength division multiplexer (3), the b input end of the wavelength division multiplexer (3) is connected to the output end of the first fiber grating array (2), and the input end of the first fiber grating array (2) is connected to the output end of the polarization controller (8). The c output terminal of the wavelength division multiplexer (3) is connected to the input terminal of the first erbium-doped fiber (4), the output terminal of the first erbium-doped fiber (4) is connected to the a port of the first optical circulator (5), the b port of the first optical circulator (5) is connected to the input terminal of the second fiber grating array (7), and the c port of the first optical circulator (5) is connected to the a input terminal of the first 1*2 coupler (6). The b output terminal of the first 1*2 coupler (6) is connected to the a input terminal of the phase modulator (9), and the c output terminal of the first 1*2 coupler (6) is connected to the input terminal of the polarization controller (8). The b output terminal of the phase modulator (9) is connected to the input terminal of the second erbium-doped fiber (10), and the c input terminal of the phase modulator (9) is connected to the c output terminal of the microprocessor (41). The output end of the second erbium-doped fiber (10) is connected to the input end of the optical isolator (11), and the output end of the optical isolator (11) is connected to the a input end of the 1*3 coupler (12). The b output terminal of the 1*3 coupler (12) is connected to the input terminal of the second photodetector (28), the c output terminal of the 1*3 coupler (12) is connected to the a port of the third optical circulator (14), and the d output terminal of the 1*3 coupler (12) is connected to the a port of the second optical circulator (13). The b port of the second optical circulator (13) is connected to the a input terminal of the second 1*2 coupler (15), and the c port of the second optical circulator (13) is connected to the input terminal of the third photodetector (29). The b port of the third optical circulator (14) is connected to the a input port of the third 1*2 coupler (21), and the c port of the third optical circulator (14) is connected to the input port of the first photodetector (27). The b output end of the second 1*2 coupler (15) is connected to the input end of the first sensing fiber (16), and the output end of the first sensing fiber (16) is connected to the input end of the first Faraday rotating mirror (18). The c output end of the second 1*2 coupler (15) is connected to the input end of the second sensing fiber (17), and the output end of the second sensing fiber (17) is connected to the input end of the second Faraday rotating mirror (19). The output end of the third 1*2 coupler (21) is connected to the input end of the third sensing fiber (22), and the output end of the third sensing fiber (22) is connected to the input end of the third Faraday rotating mirror (24). The c output end of the third 1*2 coupler (21) is connected to the input end of the fourth sensing fiber (23), and the output end of the fourth sensing fiber (23) is connected to the input end of the fourth Faraday rotating mirror (25). The output terminal of the first photodetector (27) is connected to the input terminal of the first transimpedance amplifier module (30), and the output terminal of the first transimpedance amplifier module (30) is connected to the b input terminal of the first proportional operation module (33). The output terminal of the second photodetector (28) is connected to the a input terminal of the second transimpedance amplifier module (31), the b output terminal of the second transimpedance amplifier module (31) is connected to the c input terminal of the first proportional operation module (33), and the c output terminal of the second transimpedance amplifier module (31) is connected to the b input terminal of the second proportional operation module (34). The output terminal of the third photodetector (29) is connected to the input terminal of the third transimpedance amplifier module (32), and the output terminal of the third transimpedance amplifier (32) is connected to the c input terminal of the second proportional operation module (34). The a output terminal of the first proportional operation module (33) is connected to the input terminal of the first filtering module (35), the output terminal of the first filtering module (35) is connected to the input terminal of the first demodulation module (37), and the output terminal of the first demodulation module (37) is connected to the b input terminal of the differential operation module (39). The output terminal 'a' of the second proportional operation module (34) is connected to the input terminal of the second filtering module (36), the output terminal of the second filtering module (36) is connected to the input terminal of the second demodulation module (38), and the output terminal of the second demodulation module (38) is connected to the input terminal 'c' of the differential operation module (39). The output terminal a of the differential operation module (39) is connected to the input terminal of the A / D conversion module (40), the output terminal of the A / D conversion module (40) is connected to the input terminal b of the microprocessor (41), and the output terminal a of the microprocessor (41) is connected to the input terminal of the wireless wifi module (42). The wireless Wi-Fi module (42) is wirelessly connected to the backend of the cloud server (43) via a wireless network; The communication port of the cloud server backend (43) is connected to the client (44).

2. The vibration signal noise-resistant monitoring system based on dual-path fiber optic Michelson interferometric orthogonal detection according to claim 1, characterized in that: The first sensing fiber (16), the second sensing fiber (17), the first Faraday rotator (18), and the second Faraday rotator (19) are all encapsulated inside the first sensing probe (20); The third sensing fiber (22), the fourth sensing fiber (23), the third Faraday rotator (24), and the fourth Faraday rotator (25) are all encapsulated inside the second sensing probe (26).

3. The vibration signal noise-resistant monitoring system based on dual-path fiber optic Michelson interferometric orthogonal detection according to claim 1, characterized in that: The cloud server backend (43) performs spectrum analysis and pattern recognition on the vibration data and sends the vibration data and alarm information to the client (44) to provide the client (44) with the working status of the equipment and alarm information.

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