Power OPGW optical cable data acquisition device and method based on distributed optical sensing technology

Abstract

The present invention discloses a power OPGW optical cable data acquisition device and method based on distributed optical sensing technology, and relates to the technical field of optical cable data acquisition. The technical key points of the present invention include: the OPGW optical cable data acquisition device includes a broadband laser, a first wavelength division multiplexer, an acousto-optic modulator, a first erbium-doped fiber amplifier, a first circulator, a second wavelength division multiplexer, an optical fiber to be tested, a narrow line width laser, a first coupler, a pulse generator, a second erbium-doped fiber amplifier, a Raman amplifier, a first data acquisition card, a first photodetector, a third wavelength division multiplexer, a second coupler, a second circulator, a second photodetector, a first optical filter, a third circulator, a second optical filter, a microwave source, an electro-optic modulator, an optical attenuator, a third coupler, a third photodetector, and a second data acquisition card. The present invention can realize the synchronous acquisition of temperature, strain, vibration and attenuation signals of the OPGW optical cable by using one fiber core.

Description

Technical Field

[0001] The present invention relates to the technical field of optical cable data acquisition, and in particular to a power OPGW optical cable data acquisition device and method based on distributed optical sensing technology. Background Art

[0002] OPGW optical cable places optical fiber in the ground wire of overhead high-voltage transmission line to form an optical fiber communication network on the transmission line. It has the dual functions of ground wire and communication. As the information transmission medium of power system, it plays an important role in the construction of smart grid. The OPGW optical cable placed on the top of the tower is subject to the harm caused by natural environmental changes such as ice, wind, and lightning strikes. At the same time, it is affected by factors such as construction quality, optical cable structure, and geographical location differences of towers in the tension section. OPGW faces static and dynamic tension, high temperature and lightning current, causing hardware damage, broken strands and fibers, tower collapse and other accidents, which brings hidden dangers to the safe and stable operation of OPGW optical cable.

[0003] Traditional monitoring technologies include image processing, GPS sensing, and fiber Bragg grating. Image processing is easily affected by weather, cannot work in harsh environments, and has poor reliability. The construction and daily maintenance costs of GPS system base stations are high, and the economy is insufficient. The sensing distance of fiber Bragg grating is limited. The signal transmission method, transmission distance, and capacity of existing sensors are limited, and they are easily affected by electromagnetic interference and require line power supply, which cannot meet monitoring needs. Distributed fiber optic sensing technology can achieve distributed sensing of hundreds of kilometers using existing optical fibers. It has natural advantages such as being passive, resistant to strong electromagnetic interference, no need for line power supply, and inherent safety. It has broad application prospects in power systems.

[0004] Currently, BOTDR (Brillouin optical time-domain reflectometer) is used to monitor stress, temperature, icing, and lightning strikes, and Φ-OTDR (phase-sensitive optical time-domain reflectometer) is used to monitor vibration, dancing, and icing. However, due to the complex climate environment that optical cables face, a single measurement parameter cannot accurately reflect the damage to the line. Therefore, the integration of multiple sensing mechanisms for multi-parameter sensing is of great significance for the evaluation of line status. Summary of the invention

[0005] To this end, the present invention proposes a power OPGW optical cable data acquisition device and method based on distributed optical sensing technology to solve the technical problem that existing measuring devices cannot simultaneously and accurately collect temperature, strain, vibration and attenuation signals of optical cables.

[0006] According to one aspect of the present invention, there is provided a power OPGW optical cable data acquisition device based on distributed optical sensing technology, the device comprising:

[0007] Broadband laser, first wavelength division multiplexer, acousto-optic modulator, first erbium-doped fiber amplifier, first circulator, second wavelength division multiplexer, optical fiber to be tested, narrow linewidth laser, first coupler, pulse generator, second erbium-doped fiber amplifier, Raman amplifier, first data acquisition card, first photodetector, third wavelength division multiplexer, second coupler, second circulator, second photodetector, first optical filter, third circulator, second optical filter, microwave source, electro-optic modulator, optical attenuator, third coupler, third photodetector, second data acquisition card;

[0008] The optical signal output end of the broadband laser is connected to the No. 1 port of the first wavelength division multiplexer, the optical signal output end of the narrow linewidth laser is connected to the first coupler, the first coupler is connected to the No. 2 port of the first wavelength division multiplexer and the optical signal input end of the electro-optic modulator respectively and simultaneously, the No. 3 port of the first wavelength division multiplexer is connected to the optical signal input end of the acousto-optic modulator, the microwave signal output end of the pulse generator is connected to the microwave signal loading end of the acousto-optic modulator, the optical signal output end of the acousto-optic modulator is connected to the optical signal input end of the first erbium-doped fiber amplifier, the optical signal output end of the first erbium-doped fiber amplifier is connected to the No. 1 optical signal port of the first circulator, the No. 2 optical signal port of the first circulator is connected to the No. 1 port of the second wavelength division multiplexer, the optical signal output end of the Raman amplifier is connected to the No. 2 port of the second wavelength division multiplexer, and the No. 3 port of the second wavelength division multiplexer is connected to the optical fiber to be tested;

[0009] The No. 3 optical signal port of the first circulator is connected to the optical signal input end of the second erbium-doped fiber amplifier, the optical signal output end of the second erbium-doped fiber amplifier is connected to the No. 3 port of the third wavelength division multiplexer, the No. 1 port of the third wavelength division multiplexer is connected to the optical signal input end of the first photodetector, the electrical signal output end of the first photodetector is connected to the electrical signal input end of the first data acquisition card, and the trigger signal output end of the pulse generator is connected to the trigger signal input end of the first data acquisition card;

[0010] Port No. 2 of the third wavelength division multiplexer is communicated with port No. 1 of the second coupler, port No. 2 of the second coupler is communicated with port No. 1 of the second circulator, port No. 2 of the second circulator is communicated with the first optical filter, port No. 3 of the second circulator is communicated with the optical signal input end of the second photodetector, the electrical signal output end of the second photodetector is communicated with the electrical signal input end of the second data acquisition card, and the trigger signal output end of the pulse generator is communicated with the trigger signal input end of the second data acquisition card;

[0011] Port No. 3 of the second coupler is connected to port No. 1 of the third circulator, port No. 2 of the third circulator is connected to the second optical filter, port No. 3 of the third circulator is connected to the third coupler, the trigger signal output end of the pulse generator is connected to the synchronization signal input end of the microwave source; the microwave signal output end of the microwave source is connected to the microwave signal loading end of the electro-optical modulator, the optical signal output end of the electro-optical modulator is connected to the optical attenuator, the optical attenuator is connected to the third coupler, the third coupler is connected to the optical signal input end of the third photodetector, and the electrical signal output end of the third photodetector is connected to the electrical signal input end of the second data acquisition card.

[0012] Furthermore, the broadband laser has an output optical power of 20 mW and a central wavelength of 1570 nm; the narrow-linewidth laser adopts a single-frequency narrow-linewidth fiber laser, has an output optical power of 11 mW and a wavelength of 1550.12 nm.

[0013] Furthermore, the transmission wavelength of the first wavelength division multiplexer is 1550.12nm, the transmission bandwidth is 0.22nm, and the reflection wavelength is 1552nm~1590nm; the transmission wavelength of the second wavelength division multiplexer is 1550nm~1590nm, the transmission bandwidth is 0.22nm, and the reflection wavelength is 1480nm; the transmission wavelength of the third wavelength division multiplexer is 1550.12nm, the transmission bandwidth is 0.22nm, and the reflection wavelength is 1552nm~1590nm.

[0014] Furthermore, the frequency shift of the acousto-optic modulator is 200 MHz, and the extinction ratio is 50 dB; the coupling ratio of the first coupler is 90:10, the coupling ratio of the second coupler is 50:50, and the coupling ratio of the third coupler is 50:50.

[0015] Furthermore, the output optical power of the Raman amplifier is 300mW and the wavelength is 1480nm.

[0016] Furthermore, the detection bandwidth of the first photodetector is 50 MHz, the detection bandwidth of the second photodetector is 50 MHz, and the detection bandwidth of the third photodetector is 500 MHz.

[0017] Furthermore, the central wavelength of the first optical filter is 1550.12 nm, and the bandwidth is 2 GHz; the central wavelength of the second optical filter is 1550.22 nm, and the bandwidth is 2 GHz.

[0018] According to another aspect of the present invention, a method for collecting data of an electric power OPGW optical cable based on distributed optical sensing technology is provided, and the method for collecting data of an electric power OPGW optical cable is implemented based on the above-mentioned electric power OPGW optical cable data collection device;

[0019] The power OPGW optical cable data collection method comprises:

[0020] The continuous light output by the narrow linewidth laser is divided into two upper and lower branches by the first coupler. The continuous light signal of the lower branch is modulated by the electro-optic modulator and then output as a reference light signal by the optical attenuator. The continuous light of the upper branch and the broadband continuous light signal output by the broadband laser are combined by the first wavelength division multiplexer and modulated into a pulse light signal by the acousto-optic modulator. After peak power amplification by the first erbium-doped fiber amplifier, the first circulator injects the Raman light signal output by the second wavelength division multiplexer and the Raman light signal output by the Raman amplifier into the optical fiber to be tested at the same time. The Raman light signal realizes the distributed amplification of the backscattered light signal generated by Brillouin scattering and Rayleigh scattering in the optical fiber to be tested. The backscattered light signal after distributed amplification is reflected and filtered out by the second wavelength division multiplexer to remove the Raman light signal. The remaining light signal is transmitted and injected into the second erbium-doped fiber amplifier through the first circulator for optical power amplification. Then, the broadband light signal is filtered out by the third wavelength division multiplexer and detected in real time by the first photodetector. The output photocurrent is collected in real time by the first data acquisition card to form an OTDR system.

[0021] The remaining narrowband scattered light signal is divided into two paths through the second coupler. The first narrowband scattered light signal is input through the first optical signal port of the second circulator, and injected into the first optical filter through the second optical signal port of the second circulator for filtering to obtain a Rayleigh scattered light signal, which is detected by the second photodetector. The output photocurrent is collected in real time by the second data acquisition card to form a Φ-OTDR system.

[0022] The second narrowband scattered light signal is input through the first optical signal port of the third circulator, and injected into the second optical filter through the second optical signal port of the second circulator for filtering, thereby obtaining a Brillouin scattered light signal, which is detected by the third photodetector, and the output photocurrent is collected in real time by the second data acquisition card, thus forming a BOTDR system;

[0023] The pulse generator controls the acousto-optic modulator, the microwave source, the first data acquisition card and the second data acquisition card respectively; the microwave source controls the electro-optic modulator, thereby using the same fiber core to realize synchronous acquisition of temperature, strain, vibration and attenuation signals.

[0024] The beneficial technical effects of the present invention are:

[0025] The present invention adopts BOTDR, Φ-OTDR and OTDR technologies, combined with front-end distributed first-order Raman amplification technology to realize long-distance multi-parameter OPGW optical cable monitoring, and comprehensively reflects the safety status of the optical cable. If static strain, dynamic strain and loss anomaly exist at the same position, the optical cable has a major safety hazard, thereby realizing the synchronous collection of temperature, strain, vibration and attenuation signals of the OPGW optical cable by using only the same device and the same fiber core. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The above and other objects, features and advantages of the exemplary embodiments of the present invention will become readily understood by reading the detailed description below with reference to the accompanying drawings. In the accompanying drawings, several embodiments of the present invention are shown in an exemplary and non-limiting manner, in which:

[0027] Figure 1 It is a structural schematic diagram of a power OPGW optical cable data acquisition device based on distributed optical sensing technology according to an embodiment of the present invention;

[0028] Figure 2 is a graph of optical fiber attenuation measured by OTDR technology in an embodiment of the present invention;

[0029] Figure 3 is a diagram of the Brillouin frequency shift result measured by using the BOTDR technology in an embodiment of the present invention;

[0030] Figure 4 is a strain result diagram obtained by using BOTDR technology in an embodiment of the present invention;

[0031] Figure 5 : is a signal result diagram detected by the Φ-OTDR technology in an embodiment of the present invention;

[0032] Figure 6 It is a differential three-dimensional spectrum measured by the Φ-OTDR technology in an embodiment of the present invention. DETAILED DESCRIPTION

[0033] The principles and spirit of the present invention will be described below with reference to several exemplary embodiments. It should be understood that these embodiments are provided only to enable those skilled in the art to better understand and implement the present invention, and are not intended to limit the scope of the present invention in any way. On the contrary, these embodiments are provided to make the present disclosure more thorough and complete, and to fully convey the scope of the present disclosure to those skilled in the art.

[0034] The embodiment of the present invention provides a power OPGW optical cable data acquisition device based on distributed optical sensing technology, such as Figure 1As shown, the data acquisition device includes: a broadband laser 1, a first wavelength division multiplexer 2, an acousto-optic modulator 3, a first erbium-doped fiber amplifier 4, a first circulator 5, a second wavelength division multiplexer 6, an optical fiber to be tested 7, a narrow linewidth laser 8, a first coupler 9, a pulse generator 10, a second erbium-doped fiber amplifier 11, a Raman amplifier 12, a first data acquisition card 13, a first photodetector 14, a third wavelength division multiplexer 15, a second coupler 16, a second circulator 17, a second photodetector 18, a first optical filter 19, a third circulator 20, a second optical filter 21, a microwave source 22, an electro-optic modulator 23, an optical attenuator 24, a third coupler 25, a third photodetector 26, and a second data acquisition card 27; wherein,

[0035] The optical signal output end of the broadband laser 1 is connected to the No. 1 port of the first wavelength division multiplexer 2, the optical signal output end of the narrow linewidth laser 8 is connected to the first coupler 9, the first coupler 9 is connected to the No. 2 port of the first wavelength division multiplexer 2 and the optical signal input end of the electro-optic modulator 23 respectively, the No. 3 port of the first wavelength division multiplexer 2 is connected to the optical signal input end of the acousto-optic modulator 3, the microwave signal output end of the pulse generator 10 is connected to the microwave signal loading end of the acousto-optic modulator 3, the optical signal output end of the acousto-optic modulator 3 is connected to the optical signal input end of the first erbium-doped fiber amplifier 4, the optical signal output end of the first erbium-doped fiber amplifier 4 is connected to the No. 1 optical signal port 5-1 of the first circulator 5, the No. 2 optical signal port 5-2 of the first circulator 5 is connected to the No. 1 port of the second wavelength division multiplexer 6, the optical signal output end of the Raman amplifier 12 is connected to the No. 2 port of the second wavelength division multiplexer 6, and the No. 3 port of the second wavelength division multiplexer 6 is connected to the optical fiber 7 to be tested;

[0036] The third optical signal port 5-3 of the first circulator 5 is connected to the optical signal input end of the second erbium-doped fiber amplifier 11, the optical signal output end of the second erbium-doped fiber amplifier 11 is connected to the third port of the third wavelength division multiplexer 15, the first port of the third wavelength division multiplexer 15 is connected to the optical signal input end of the first photodetector 14, the electrical signal output end of the first photodetector 14 is connected to the electrical signal input end of the first data acquisition card 13, and the trigger signal output end of the pulse generator 10 is connected to the trigger signal input end of the first data acquisition card 13; the first data acquisition card 13 acquires OTDR data;

[0037] The second port of the third wavelength division multiplexer 15 is connected to the first port of the second coupler 16, the second optical signal port of the second coupler 16 is connected to the first port 17-1 of the second circulator 17, the second port 17-2 of the second circulator 17 is connected to the first optical filter 19, the third port 17-3 of the second circulator 17 is connected to the optical signal input end of the second photodetector 18, the electrical signal output end of the second photodetector 18 is connected to the electrical signal input end of the second data acquisition card 27, and the trigger signal output end of the pulse generator 10 is connected to the trigger signal input end of the second data acquisition card 27; the first channel of the second data acquisition card 27 acquires Φ-OTDR data;

[0038] Port No. 3 of the second coupler 16 is connected to port No. 1 20-1 of the third circulator 20, port No. 20-2 of the third circulator 20 is connected to the second optical filter 21, port No. 3 20-3 of the third circulator 20 is connected to the third coupler 25, the trigger signal output end of the pulse generator 10 is connected to the synchronization signal input end of the microwave source 22; the microwave signal output end of the microwave source 22 is connected to the microwave signal loading end of the electro-optical modulator 23, the optical signal output end of the electro-optical modulator 23 is connected to the optical attenuator 24, the optical attenuator 24 is connected to the third coupler 25, the third coupler 25 is connected to the optical signal input end of the third photodetector 26, the electrical signal output end of the third photodetector 26 is connected to the electrical signal input end of the second data acquisition card 27; the second channel of the second data acquisition card 27 acquires BOTDR data.

[0039] In this embodiment, preferably, the broadband laser 1 has an output optical power of 20 mW and a central wavelength of 1570 nm.

[0040] In this embodiment, preferably, the transmission wavelength of the first wavelength division multiplexer 2 is 1550.12 nm, the transmission bandwidth is 0.22 nm, and the reflection wavelength is 1552 nm to 1590 nm.

[0041] In this embodiment, preferably, the frequency shift of the acousto-optic modulator 3 is 200 MHz, and the extinction ratio is 50 dB.

[0042] In this embodiment, preferably, the transmission wavelength of the second wavelength division multiplexer 6 is 1550nm-1590nm, the reflection wavelength is 1480nm, and the transmission bandwidth is 0.22nm.

[0043] In this embodiment, the narrow linewidth laser 8 is a single-frequency narrow linewidth fiber laser with an output optical power of 11 mW and a wavelength of 1550.12 nm.

[0044] In this embodiment, preferably, the coupling ratio of the first coupler 9 is 90:10.

[0045] In this embodiment, preferably, the output optical power of the Raman amplifier 12 is 300 mW and the wavelength is 1480 nm.

[0046] In this embodiment, preferably, the detection bandwidth of the first photodetector 14 is 50 MHz.

[0047] In this embodiment, preferably, the transmission wavelength of the third wavelength division multiplexer 15 is 1550.12 nm, the transmission bandwidth is 0.22 nm, and the reflection wavelength is 1552 nm to 1590 nm.

[0048] In this embodiment, preferably, the coupling ratio of the second coupler 16 is 50:50.

[0049] In this embodiment, preferably, the detection bandwidth of the second photodetector 18 is 50 MHz.

[0050] In this embodiment, preferably, the central wavelength of the first optical filter 19 is 1550.12 nm and the bandwidth is 2 GHz.

[0051] In this embodiment, preferably, the central wavelength of the optical filter 21 is 1550.22 nm and the bandwidth is 2 GHz.

[0052] In this embodiment, preferably, the coupling ratio of the third coupler 25 is 50:50.

[0053] In this embodiment, preferably, the detection bandwidth of the third photodetector 26 is 500 MHz.

[0054] The power OPGW optical cable data acquisition device based on distributed optical sensing technology described in the embodiment of the present invention combines BOTDR, Φ-OTDR and OTDR technologies to realize multi-parameter sensing of temperature, strain, vibration and attenuation; the process of realizing optical cable data acquisition using the above-mentioned power OPGW optical cable data acquisition device is as follows:

[0055] The continuous light output by the narrow linewidth laser 8 is divided into two branches, an upper branch and an lower branch, by the first coupler 9. The continuous light signal of the lower branch is modulated by the electro-optic modulator 23 and then outputted as a reference light signal by the optical attenuator 24. The continuous light of the upper branch is combined with the broadband continuous light signal output by the broadband laser 1 by the first wavelength division multiplexer 2 and then modulated into a pulse light signal by the acousto-optic modulator 3. The peak power is amplified by the first erbium-doped fiber amplifier 4 and then injected into the second wavelength division multiplexer 6 and the Raman light signal output by the Raman amplifier 12 through the first circulator 5 into the optical fiber to be tested 7 at the same time. The Raman light signal realizes the backscattering caused by Brillouin scattering and Rayleigh scattering in the optical fiber to be tested. Distributed amplification of optical signals improves signal quality and sensing distance; the backscattered optical signal after distributed amplification is reflected and filtered out by the second wavelength division multiplexer 6 to remove the Raman optical signal, and the remaining optical signal is transmitted and injected into the second erbium-doped fiber amplifier 11 through the first circulator 5 for optical power amplification, and then the broadband optical signal of the 1570nm band is filtered out by the third wavelength division multiplexer 15, and is detected in real time by the first photodetector 14, and the output photocurrent is collected in real time by the first data acquisition card 13 to form an OTDR system; by taking logarithmic processing of the OTDR signal, the distance of the OPGW optical cable and the attenuation and welding position along the line are located and measured;

[0056] The remaining narrowband scattered light signal is divided into two paths through the second coupler 16. The first narrowband scattered light signal is input through the first optical signal port of the second circulator 17, and injected into the first optical filter 19 for filtering through the second optical signal port of the second circulator 17 to obtain a Rayleigh scattered light signal, which is detected by the second photodetector 18. The output photocurrent is collected in real time by the second data acquisition card 27 to form a Φ-OTDR system; by averaging and differential processing of the Rayleigh signal, real-time positioning and measurement of vibration along the OPGW optical cable are achieved;

[0057] The second narrowband scattered light signal is input through the first optical signal port of the third circulator 20, and is injected into the second optical filter 21 for filtering through the second optical signal port of the second circulator 17 to obtain a Brillouin scattered light signal, which is detected by the third photodetector 26, and the output photocurrent is collected in real time by the second data acquisition card 27 to form a BOTDR system; the Brillouin signal is subjected to Lorentz fitting to obtain a Brillouin spectrum, and the real-time positioning and measurement of the temperature and strain along the OPGW optical cable are achieved through the movement size of the Brillouin spectrum;

[0058] The pulse generator 10 controls the acousto-optic modulator 3, the microwave source 22, the first data acquisition card 13 and the second data acquisition card 27 respectively; the microwave source 22 controls the electro-optic modulator 23, thereby realizing the synchronous acquisition of temperature, strain, vibration and attenuation signals.

[0059] The first data acquisition card 13 is used to collect OTDR signals, and the host computer is used to measure and analyze events. OTDR uses the principles of Rayleigh scattering and Fresnel reflection, and can be used to measure information such as the length / attenuation / breakage, return loss, fusion loss, and reflectivity of optical fibers. When light is transmitted in an optical fiber, the light is Rayleigh scattered due to the defects of the optical fiber itself and the non-uniformity of the doping components. In addition, when light encounters the boundary of two media with different refractive indices, such as connectors, mechanical splices, breaks, or optical fiber interruptions, Fresnel reflection occurs, and part of the scattered and reflected light will return along the optical fiber. It is currently the most important detection technology for power communication optical cables, and is used to measure whether there is a broken core, large loss, or large attenuation.

[0060] The BOTDR time domain signal is collected by the second acquisition card 27. The BOTDR system uses the linear relationship between the change in the frequency shift of the spontaneous Brillouin scattered light in the optical fiber and the axial strain and temperature of the optical fiber to measure the temperature and strain along the optical fiber. The microwave source is used to control the frequency sweep to obtain the time domain signal at different frequencies, and a three-dimensional Brillouin scattering power spectrum of "frequency-distance-intensity" at each position along the optical fiber is constructed. The frequency domain signal at each position along the optical fiber is fitted with a Lorentz curve to obtain the Brillouin scattering frequency shift. The linear relationship between the change in the frequency shift of the spontaneous Brillouin scattered light in the optical fiber and the axial strain and temperature of the optical fiber is used to measure the temperature and strain along the optical fiber. The result reflects whether there is a strain area in the optical cable, and the static stress area of ​​the optical cable is measured.

[0061] The second acquisition card 27 is used to collect the Φ-OTDR time domain signal. The Φ-OTDR uses the Rayleigh scattering effect in the optical fiber. When the sensing optical fiber is affected by external vibration, the refractive index of the optical fiber at the corresponding position will change, thereby causing the light phase at the corresponding position to change, and further causing the amplitude of the backward Rayleigh scattering interference signal to change. The final interference result will directly reflect the location of the disturbance point, so that the specific location of the external interference can be determined. The time domain signal obtained by the host computer is differentiated from the previous set of time domain signals to obtain a differential signal, and it is determined whether the differential signal is greater than the threshold. If it is greater than the threshold, the differential signal within a period of time is saved, and the differential three-dimensional spectrum composed of multiple differential signals at the point where the differential signal is greater than the threshold is Fourier transformed to obtain the frequency of the disturbance area, so as to determine whether the optical cable is affected by dynamic stress and whether the optical cable vibrates.

[0062] Combining the test results of OTDR, BOTDR, and Φ-OTDR, the safety status of the optical cable is comprehensively reflected. If static strain, dynamic strain, and loss anomalies exist at the same position, there are major safety hazards in the optical cable. This enables the synchronous collection of temperature, strain, vibration, and attenuation signals of the OPGW optical cable using only the same device and the same fiber core.

[0063] Although the spirit and principle of the present invention have been described with reference to several specific embodiments, it should be understood that the present invention is not limited to the disclosed specific embodiments, and the division of various aspects does not mean that the features in these aspects cannot be combined to benefit, and such division is only for the convenience of expression. The present invention is intended to cover various modifications and equivalent arrangements included in the spirit and scope of the attached claims.

Claims

1. The power OPGW optical cable data acquisition device based on distributed optical sensing technology is characterized by: include: Broadband laser (1), a first wavelength division multiplexer (2), an acousto-optic modulator (3), a first erbium-doped fiber amplifier (4), a first circulator (5), a second wavelength division multiplexer (6), an optical fiber to be tested (7), a narrow linewidth laser (8), a first coupler (9), a pulse generator (10), a second erbium-doped fiber amplifier (11), a Raman amplifier (12), a first data acquisition card (13), a first photodetector (14), a third wavelength division multiplexer (15), a second coupler (16), a second circulator (17), a second photodetector (18), a first optical filter (19), a third circulator (20), a second optical filter (21), a microwave source (22), an electro-optic modulator (23), an optical attenuator (24), a third coupler (25), a third photodetector (26), and a second data acquisition card (27); The optical signal output end of the broadband laser (1) is connected to the first port of the first wavelength division multiplexer (2), the optical signal output end of the narrow line width laser (8) is connected to the first coupler (9), the first coupler (9) is connected to the second port of the first wavelength division multiplexer (2) and the optical signal input end of the electro-optic modulator (23) respectively, the third port of the first wavelength division multiplexer (2) is connected to the optical signal input end of the acousto-optic modulator (3), the microwave signal output end of the pulse generator (10) is connected to the microwave signal loading end of the acousto-optic modulator (3), and the acoustic The optical signal output end of the optical modulator (3) is connected to the optical signal input end of the first erbium-doped fiber amplifier (4), the optical signal output end of the first erbium-doped fiber amplifier (4) is connected to the first optical signal port (5-1) of the first circulator (5), the second optical signal port (5-2) of the first circulator (5) is connected to the first port of the second wavelength division multiplexer (6), the optical signal output end of the Raman amplifier (12) is connected to the second port of the second wavelength division multiplexer (6), and the third port of the second wavelength division multiplexer (6) is connected to the optical fiber to be tested (7); The third optical signal port (5-3) of the first circulator (5) is connected to the optical signal input end of the second erbium-doped fiber amplifier (11), the optical signal output end of the second erbium-doped fiber amplifier (11) is connected to the third port of the third wavelength division multiplexer (15), the first port of the third wavelength division multiplexer (15) is connected to the optical signal input end of the first photodetector (14), the electrical signal output end of the first photodetector (14) is connected to the electrical signal input end of the first data acquisition card (13), and the trigger signal output end of the pulse generator (10) is connected to the trigger signal input end of the first data acquisition card (13); The second port of the third wavelength division multiplexer (15) is connected to the first port of the second coupler (16), the second optical signal port of the second coupler (16) is connected to the first port (17-1) of the second circulator (17), the second port (17-2) of the second circulator (17) is connected to the first optical filter (19), the third port (17-3) of the second circulator (17) is connected to the optical signal input end of the second photodetector (18), the electrical signal output end of the second photodetector (18) is connected to the electrical signal input end of the second data acquisition card (27), and the trigger signal output end of the pulse generator (10) is connected to the trigger signal input end of the second data acquisition card (27); The third port of the second coupler (16) is in communication with the first port (20-1) of the third circulator (20), the second port (20-2) of the third circulator (20) is in communication with the second optical filter (21), the third port (20-3) of the third circulator (20) is in communication with the third coupler (25), the trigger signal output end of the pulse generator (10) is in communication with the synchronization signal input end of the microwave source (22); the microwave signal output end of the microwave source (22) is in communication with the microwave signal loading end of the electro-optic modulator (23), the optical signal output end of the electro-optic modulator (23) is in communication with the optical attenuator (24), the optical attenuator (24) is in communication with the third coupler (25), the third coupler (25) is in communication with the optical signal input end of the third photoelectric detector (26), and the electrical signal output end of the third photoelectric detector (26) is in communication with the electrical signal input end of the second data acquisition card (27).

2. The power OPGW optical cable data acquisition device based on distributed optical sensing technology according to claim 1 is characterized in that: The broadband laser (1) has an output optical power of 20 mW and a central wavelength of 1570 nm; the narrow linewidth laser (8) adopts a single-frequency narrow linewidth fiber laser, has an output optical power of 11 mW and a wavelength of 1550.12 nm.

3. The power OPGW optical cable data acquisition device based on distributed optical sensing technology according to claim 1 is characterized in that: The transmission wavelength of the first wavelength division multiplexer (2) is 1550.12 nm, the transmission bandwidth is 0.22 nm, and the reflection wavelength is 1552 nm to 1590 nm; the transmission wavelength of the second wavelength division multiplexer (6) is 1550 nm to 1590 nm, the transmission bandwidth is 0.22 nm, and the reflection wavelength is 1480 nm; the transmission wavelength of the third wavelength division multiplexer (15) is 1550.12 nm, the transmission bandwidth is 0.22 nm, and the reflection wavelength is 1552 nm to 1590 nm.

4. The power OPGW optical cable data acquisition device based on distributed optical sensing technology according to claim 1 is characterized in that: The acousto-optic modulator (3) has a shift frequency of 200 MHz and an extinction ratio of 50 dB.

5. The power OPGW optical cable data acquisition device based on distributed optical sensing technology according to claim 1 is characterized in that: The coupling ratio of the first coupler (9) is 90:10, the coupling ratio of the second coupler (16) is 50:50, and the coupling ratio of the third coupler (25) is 50:

50.

6. The power OPGW optical cable data acquisition device based on distributed optical sensing technology according to claim 1 is characterized in that: The output optical power of the Raman amplifier (12) is 300 mW and the wavelength is 1480 nm.

7. The power OPGW optical cable data acquisition device based on distributed optical sensing technology according to claim 1 is characterized in that: The detection bandwidth of the first photodetector (14) is 50 MHz, the detection bandwidth of the second photodetector (18) is 50 MHz, and the detection bandwidth of the third photodetector (26) is 500 MHz.

8. The power OPGW optical cable data acquisition device based on distributed optical sensing technology according to claim 1 is characterized in that: The central wavelength of the first optical filter (19) is 1550.12 nm and the bandwidth is 2 GHz; the central wavelength of the second optical filter (21) is 1550.22 nm and the bandwidth is 2 GHz.

9. A method for collecting data of power OPGW optical cables based on distributed optical sensing technology, characterized in that: The power OPGW optical cable data collection method is implemented based on the power OPGW optical cable data collection device according to any one of claims 1 to 8; The power OPGW optical cable data collection method comprises: The continuous light output by the narrow linewidth laser (8) is divided into two upper and lower branches by the first coupler (9); the continuous light signal of the lower branch is modulated by the electro-optic modulator (23) and then output as a reference light signal by the optical attenuator (24); the continuous light of the upper branch is combined with the broadband continuous light signal output by the broadband laser (1) by the first wavelength division multiplexer (2) and then modulated into a pulse light signal by the acousto-optic modulator (3); the pulse light signal is peak-power amplified by the first erbium-doped fiber amplifier (4) and then injected into the second wavelength division multiplexer (6) through the first circulator (5) and simultaneously injected into the optical fiber to be tested with the Raman light signal output by the Raman amplifier (12). (7), the Raman optical signal realizes distributed amplification of the backscattered optical signal generated by Brillouin scattering and Rayleigh scattering in the optical fiber to be tested (7); the backscattered optical signal after distributed amplification is reflected and filtered out by the second wavelength division multiplexer (6) to remove the Raman optical signal, and the remaining optical signal is transmitted through the first circulator (5) and injected into the second erbium-doped optical fiber amplifier (11) for optical power amplification, and then the broadband optical signal is filtered out by the third wavelength division multiplexer (15), and is detected in real time by the first photodetector (14), and the output photocurrent is collected in real time by the first data acquisition card (13), forming an OTDR system; The remaining narrowband scattered light signal is divided into two paths through the second coupler (16), the first narrowband scattered light signal is input through the first optical signal port of the second circulator (17), injected into the first optical filter (19) through the second optical signal port of the second circulator (17) for filtering, and a Rayleigh scattered light signal is obtained, which is detected by the second photodetector (18), and the output photocurrent is collected in real time by the second data acquisition card (27), thereby forming a Φ-OTDR system; The second narrow-band scattered light signal is input through the first optical signal port of the third circulator (20), injected into the second optical filter (21) through the second optical signal port of the second circulator (17) for filtering, and a Brillouin scattered light signal is obtained, which is detected by the third photodetector (26), and the output photocurrent is collected in real time by the second data acquisition card (27), thereby forming a BOTDR system; The pulse generator (10) controls the acousto-optic modulator (3), the microwave source (22), the first data acquisition card (13) and the second data acquisition card (27) respectively; the microwave source (22) controls the electro-optic modulator (23), thereby using the same fiber core to achieve synchronous acquisition of temperature, strain, vibration and attenuation signals.

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