Superconducting quench monitoring system and quench monitoring method

Abstract

The application provides a superconducting quench monitoring system and a quench monitoring method. The superconducting quench monitoring system comprises an optical time domain reflectometer module and a Mach-Zehnder interferometer module; the Mach-Zehnder interferometer module and the optical time domain reflectometer module have a shared component; the shared component comprises a laser, an electro-optic modulator, a circulator, a sensing optical fiber, a reference optical fiber and the like; the optical time domain reflectometer module further comprises a first polarization beam splitter, a second polarization beam splitter, a first data acquisition and processing system and the like; the Mach-Zehnder interferometer module comprises a second polarization controller, a second data acquisition system and the like; both modules of the application utilize polarization beam splitting technology, which can eliminate the influence of polarization scattering of a long-distance monitoring system; the Mach-Zehnder interferometer module and the optical time domain reflectometer module of the application have a shared component, which can greatly save costs; and the application jointly monitors the same external quench signal, which can further improve the accuracy of system monitoring.

Description

Technical Field

[0001] This invention relates to the field of superconductivity, specifically to a superconducting quench monitoring system and method, particularly to a high-temperature superconducting quench online monitoring system, especially to a novel distributed optical fiber high-temperature superconducting quench detection system, and more specifically to a high-temperature superconducting quench detection system based on composite optical fiber sensing technology. Background Technology

[0002] Superconductivity refers to a conductor whose resistance approaches zero at a certain temperature. Due to its zero resistance and ability to withstand large currents, it has broad application prospects in power transmission and controlled nuclear fusion magnetic confinement. In the early stages of superconductivity discovery, the property of near-zero resistance was achieved at liquid helium temperatures; this is known as low-temperature superconductivity. With further advancements, research has revealed that certain materials can also achieve zero resistance at liquid nitrogen temperatures; this is called high-temperature superconductivity. The discovery of high-temperature superconductivity represents another significant step forward in the application of next-generation technologies.

[0003] High-temperature superconductivity has made initial progress and is gradually being applied in fields such as electronics, biomedicine, and science and engineering. Superconductors exist in a superconducting state with zero resistance below their critical temperature. However, their ability to conduct current is limited; they cannot conduct current indefinitely. That is, when the current exceeds a certain value, the superconductor will transition from the superconducting state to a normal state, i.e., it loses its superconductivity. Under the influence of a large current, the normal-state conductor heats up intensely and transfers heat to surrounding conductors, causing the normal state to gradually spread. The accumulated heat further expands, eventually burning out the superconductor. If we cut off the operating current in the early stages of superconductivity loss, we can largely avoid the burnout of the superconductor. Therefore, real-time monitoring of superconductivity loss is extremely important.

[0004] Traditional online monitoring methods for quench loss in low-temperature superconducting systems mainly rely on voltage methods. However, since the working environment of superconductors is characterized by high current and strong magnetic fields, this can cause significant interference to the use of voltage characteristics to monitor quench loss behavior.

[0005] Therefore, there is an urgent need to propose a new method for testing superconducting quench. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the purpose of this invention is to provide a superconducting quench monitoring system and quench monitoring method.

[0007] A superconducting quench monitoring system according to the present invention includes an optical time-domain reflectometer module and a Mach-Zehnder interferometer module;

[0008] The Mach-Zehnder interferometer module and the optical time-domain reflectometer module share common components;

[0009] The Mach-Zehnder interferometer module and the optical time-domain reflectometer module can simultaneously monitor external disturbances in real time.

[0010] Preferably, the common components include a laser, an electro-optic modulator, a first beam splitter, a circulator, a sensing fiber, a reference fiber, and a second beam splitter.

[0011] The laser, electro-optic modulator, and first beam splitter are arranged in sequence. The first optical signal split by the first beam splitter enters the circulator, and the circulator is connected to one end of the sensing optical fiber.

[0012] The second optical signal output of the first beam splitter is connected to the second beam splitter via a reference optical fiber, and the first output of the second beam splitter is connected to a reference optical fiber.

[0013] Preferably, the optical time domain reflectometer module further includes a first polarization beamsplitter, a second polarization beamsplitter, a first compensator, a first polarization controller, a first coupler, a second coupler, a first balanced photodetector, a second balanced photodetector, and a first data acquisition and processing system;

[0014] The circulator transmits the optical signal to the first polarization beam splitter, which splits the light into first P-polarized light and first S-polarized light.

[0015] The optical signal split from the second outlet of the second beam splitter passes sequentially through the first polarization controller and the first compensator, and arrives at the second polarization beam splitter, which splits the light into second P-polarized light and second S-polarized light.

[0016] The first P-polarized light and the second P-polarized light are coupled in the first coupler, and then pass through the first balanced photodetector to reach the first data acquisition and processing system;

[0017] The first S-polarized light and the second S-polarized light are coupled in the first coupler, and then reach the first data acquisition and processing system through the second balanced photodetector.

[0018] Preferably, the Mach-Zehnder interferometer module further includes a second polarization controller, a second compensator, a third polarization beam splitter, a fourth polarization beam splitter, a third coupler, a fourth coupler, a third balanced photodetector, a fourth balanced photodetector, and a second data acquisition system.

[0019] The other end of the sensing fiber is connected to a third polarization beam splitter, which splits the light into third P-polarized light and third S-polarized light.

[0020] The first outlet of the second beam splitter, the second polarization controller, the second compensator, and the fourth polarization beam splitter are connected in sequence via a reference fiber.

[0021] Preferably, the sensing optical fiber is provided with a superconducting tape connection surface.

[0022] Preferably, the superconducting tape connection surface is connected to the external superconducting tape via epoxy resin adhesive.

[0023] Preferably, the splitting ratio of the second beam splitter is 1:99.

[0024] Preferably, the first beam splitter is a 3dB beam splitter.

[0025] Preferably, the sensing optical fiber is a distributed optical fiber.

[0026] According to the quench detection method provided by the present invention, using the superconducting quench detection system, the method further includes the following steps:

[0027] Step 1: The laser emits laser light, which is modulated into pulsed light by an electro-optic modulator and then enters the first beam splitter. The first beam splitter splits the light into two beams of equal power, namely the probe light and the reference light.

[0028] Step 2: The probe light enters the sensing fiber through the circulator, and the backscattered Rayleigh light generated in the sensing fiber enters the first polarization beam splitter through the circulator and is split into P and S polarizations.

[0029] Step 3: The light entering the reference fiber is split into two beams, a strong beam and a weak beam, by the second beam splitter;

[0030] The weak beam is introduced into the first polarization controller, then passes through the first compensator, and reaches the second polarization beam splitter. The second polarization beam splitter splits the light into P-polarized and S-polarized beams, which then couple and interfere with the P-polarized and S-polarized light split from the first polarization beam splitter in the second coupler and the first coupler, respectively.

[0031] Step 4: The optical signal emitted from the first coupler passes through the first balanced photodetector and enters the first data acquisition and processing system;

[0032] The optical signal emitted from the second coupler enters the first data acquisition and processing system via the second balanced photodetector.

[0033] The OTDR image is obtained using the first data acquisition and processing system;

[0034] Step 5: The optical waveguide propagating in the sensing fiber is split into P- and S-polarized light by the third polarization beam splitter. The strong light split from the reference fiber by the second beam splitter passes through the second polarization controller and the second compensator and enters the fourth polarization beam splitter to be split into P- and S-polarized light.

[0035] Step 6: The corresponding polarized beams generated by the third and fourth polarization beam splitters are coupled and interfered at the third and fourth couplers, respectively.

[0036] Step 7: The optical signal emitted from the third coupler passes through the third balanced photodetector and enters the second data acquisition system;

[0037] The optical signal emitted from the fourth coupler enters the first and second data acquisition systems via the fourth balanced photodetector.

[0038] The MZIS image was obtained using the second data acquisition system.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] 1. This invention does not use the voltage method principle for quench detection, has strong anti-electromagnetic interference capability, avoids the adverse effects caused by the strong electromagnetic environment around the superconductor, and will not become a new source of electromagnetic interference.

[0041] 2. Both modules of this invention utilize polarization beam splitting technology, which can eliminate the influence of polarization scattering in long-distance monitoring systems and improve signal stability and accuracy.

[0042] 3. The Mach-Zehnder interferometer module and the optical time-domain reflectometer module of this invention share components, which can save costs to a great extent compared with separate OTDR and MZIS monitoring systems. Moreover, since they use the forward and backscattered signals of the same beam of light, they jointly monitor the same external quench signal, which can further improve the accuracy of system monitoring. Attached Figure Description

[0043] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0044] Figure 1 This is a schematic diagram of the structure of the present invention;

[0045] Figure 2 This is a schematic diagram of the optical time domain reflectometer module;

[0046] Figure 3 This is a schematic diagram of the Mach-Zehnder interferometer module.

[0047] The diagram shows:

[0048] Detailed Implementation

[0049] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0050] This invention provides a superconducting quench monitoring system, including an optical time domain reflectometer module (OTDR module) and a Mach-Zehnder interferometer module (MZIS module);

[0051] The Mach-Zehnder interferometer module and the optical time-domain reflectometer module share common components; the Mach-Zehnder interferometer module and the optical time-domain reflectometer module can simultaneously monitor external disturbances in real time;

[0052] The shared components include a laser 1, an electro-optic modulator 2, a first beam splitter 3, a circulator 4, a sensing fiber 5, a reference fiber 6, and a second beam splitter 7. The laser 1, the electro-optic modulator 2, and the first beam splitter 3 are arranged sequentially. The first optical signal (i.e., the probe light) split by the first beam splitter 3 enters the circulator 4, and the circulator 4 is connected to one end of the sensing fiber 5. The second optical signal (i.e., the sensing light) outlet of the first beam splitter 3 is connected to the second beam splitter 7 through the reference fiber 6, and the first outlet (i.e., the high-intensity light outlet) of the second beam splitter 7 is connected to the reference fiber 6.

[0053] The optical time-domain reflectometer module also includes a first polarization beam splitter 8, a second polarization beam splitter 9, a first compensator 10, a first polarization controller 11, a first coupler 12, a second coupler 13, a first balanced photodetector 14, a second balanced photodetector 15, and a first data acquisition and processing system 16.

[0054] The circulator 4 transmits the optical signal to the first polarization beam splitter 8, which splits the light into first P-polarized light and first S-polarized light.

[0055] The light signal (i.e. weak light) split from the second outlet of the second beam splitter 7 passes sequentially through the first polarization controller 11 and the first compensator 10, and arrives at the second polarization beam splitter 9. The second polarization beam splitter 9 splits the light into second P-polarized light and second S-polarized light.

[0056] The first P-polarized light and the second P-polarized light are coupled in the first coupler 12, and then reach the first data acquisition and processing system 16 through the first balanced photodetector 14.

[0057] The first S-polarized light and the second S-polarized light are coupled in the first coupler 12, and then reach the first data acquisition and processing system 16 through the second balanced photodetector 15.

[0058] The Mach-Zehnder interferometer module includes a second polarization controller 17, a second compensator 18, a third polarization beam splitter 19, a fourth polarization beam splitter 20, a third coupler 21, a fourth coupler 22, a third balanced photodetector 23, a fourth balanced photodetector 24, and a second data acquisition system 25. The other end of the sensing fiber 5 is connected to the third polarization beam splitter 19, which splits light into third P-polarized light and third S-polarized light. The first outlet of the second beam splitter 7, the second polarization controller 17, the second compensator 18, and the fourth polarization beam splitter 20 are sequentially connected via a reference fiber 6. In a preferred embodiment, the length of the reference fiber 6 between the first beam splitter 3 and the second beam splitter 7 is greater than the length of the reference fiber 6 between the second beam splitter 7 and the fourth polarization beam splitter 20.

[0059] In a preferred embodiment, the sensing fiber is provided with a superconducting tape connection surface. Preferably, the contact portion between the sensing fiber 5 and the superconducting tape directly serves as the connection surface between the fiber and the superconducting tape, i.e., the connection surface is the superconducting tape connection surface of the sensing fiber. The superconducting tape connection surface is connected to the external superconducting tape using epoxy resin adhesive. The splitting ratio of the second beam splitter 7 is 1:99. The first beam splitter 3 is a 3dB beam splitter. In a preferred embodiment, both the first polarization controller 11 and the second polarization controller 17 are polarization maintaining devices.

[0060] A quench detection method, employing the aforementioned superconducting quench detection system, further includes the following steps:

[0061] Step 1: Laser 1 emits a narrow linewidth laser beam, which is modulated into pulsed light by an electro-optic modulator and then enters the first beam splitter 3. The first beam splitter 3 splits the light into two beams of equal power, namely the probe beam and the reference beam.

[0062] Step 2: The probe light enters the sensing fiber 5 through the circulator 4. The backscattered Rayleigh light generated in the sensing fiber 5 enters the first polarization beam splitter 8 through the circulator 4 and is split into P and S polarizations.

[0063] Step 3: The light entering the reference fiber 6 is split into two beams, a strong beam and a weak beam, by the second beam splitter 7;

[0064] The weak beam is introduced into the first polarization controller 11 to ensure that the power of the two polarization states of the light remains consistent; then it passes through the first compensator 10 to compensate for the optical path difference between the reference light and the probe light; and then reaches the second polarization beam splitter 9, which splits the light into P polarization and S polarization, and then couples and interferes with the P polarization and S polarization light split by the first polarization beam splitter 8 respectively with the second coupler 13 and the first coupler 12.

[0065] Step 4: The optical signal emitted from the first coupler 12 passes through the first balanced photodetector 14 and enters the first data acquisition and processing system 16;

[0066] The optical signal emitted from the second coupler 13 enters the first data acquisition and processing system 16 via the second balanced photodetector 15;

[0067] The OTDR image is obtained using the first data acquisition and processing system 16.

[0068] Step 5: The optical waveguide propagating in the forward direction in the sensing fiber 5 is split into P- and S-polarized light by the third polarization beam splitter 19. The strong light split from the reference fiber 6 by the second beam splitter 7 passes through the second polarization controller 17 and the second compensator 18 and enters the fourth polarization beam splitter 20 to be split into P- and S-polarized light.

[0069] Step 6: The corresponding polarized beams generated by the third polarization beam splitter 19 and the fourth polarization beam splitter 20 are coupled and interfered with each other at the third coupler 21 and the fourth coupler 22, respectively.

[0070] Step 7: The optical signal emitted from the third coupler 21 passes through the third balanced photodetector 23 and enters the second data acquisition system 25;

[0071] The optical signal emitted from the fourth coupler 22 enters the first data acquisition and second data acquisition system 25 via the fourth balanced photodetector 24;

[0072] The MZIS image is obtained using the second data acquisition system 25.

[0073] The first data acquisition and processing system 16 and the second data acquisition system 25 utilize the forward optical waveguide and the back Rayleigh scattering light signal in the sensing fiber, respectively. They do not conflict with each other, making fuller use of the detection light and further ensuring the accuracy of the detection.

[0074] In using this invention, the sensing fiber 5 is attached to the surface of a high-temperature superconducting tape using epoxy resin adhesive. The tape with the sensing fiber attached and the reference fiber 6 are simultaneously immersed in liquid nitrogen. After the temperature reaches equilibrium, a narrow-linewidth laser emitted by the laser source is modulated into pulsed light by an electro-optic modulator for detection along the path. When the superconductor is not operating (no current flows), the power spectra output by the OTDR and MZIS are relatively stable (there may be slight, slow changes due to environmental disturbances), with no obvious abrupt changes. At the instant the operating current is applied to the superconductor, due to the Lorentz force, the superconductor undergoes violent deformation. At this time, the curves on the power spectra of the OTDR and MZIS change drastically until the various forces within the superconductor reach equilibrium, and the power spectrum images of the OTDR and MZIS return to a relatively stable state (at this point, there may also be slight, slow changes due to external environmental disturbances). Under conditions such as a disturbance overcurrent, local hotspot, or complex electromagnetic field changes, a high-temperature superconductor experiences localized quenching. The conductor in the quenched region transitions from a superconducting state to a normal state and rapidly heats up under the operating current, causing deformation. This sudden disturbance is transmitted to the sensing fiber, causing a change in the fiber's refractive index at that location. This further leads to abrupt changes in the amplitude and phase of the probe light transmitted within the probe fiber. Coupled with the reference light, this results in a sudden change in the ultimately acquired signal. In the MZIS power spectrum image, this manifests as a sudden change starting from a certain moment (specifically, a sharp fluctuation in amplitude after normalization of the power spectrum). If the quenched region spreads further, the severity of the image change will increase further. Unless the superconductor returns to its superconducting state after the quench disappears, the MZIS image will not return to the stable state it was in when the superconductor was operating normally; otherwise, the abruptly changed image will persist. On an OTDR power spectrum image, this manifests as a sudden increase in power at a specific location at a certain moment. If the superconducting quench region spreads, the abrupt change area on the OTDR image will also expand accordingly. When the quench region returns to the superconducting state at a certain moment, the abrupt change area on the image will gradually shrink until it returns to the stable state before the quench. The occurrence time of the abrupt change on both images represents the onset time of the superconductor quench, and the abrupt change area on the OTDR image represents the location of the superconductor quench region. Therefore, this system can be used to obtain the onset time and location of the superconductor quench, achieving the purpose of real-time monitoring of superconductor quench. Subsequently, the quench detection system provides a trigger signal, causing the energy release device in the corresponding superconducting protection system to start, completing the quench protection.

[0075] The working principle of this invention is as follows:

[0076] During normal operation, the sensing light in the sensing fiber 5 (also known as the probe fiber) and the probe light in the reference fiber couple and interfere, resulting in a stable or slightly varying (due to minor disturbances in the external environment) signal after data acquisition and processing. Under a disturbance (overcurrent, local hotspots, complex electromagnetic field changes, etc.), the high-temperature superconductor locally loses its quench. This loss of quench generates significant Joule heating, causing a temperature increase and deformation. This sudden disturbance propagates to the sensing fiber, altering its refractive index at that location. This further causes abrupt changes in the amplitude and phase of the probe light propagating within the sensing fiber, resulting in abrupt changes in the final acquired signal after coupling with the reference light. The OTDR module outputs a power spectrum image of the backscattered Rayleigh light as a function of its power and position, while the MZIS module outputs a power spectrum image of the forward waveguide power as a function of time. Because the OTDR and MZIS modules reuse the sensing fiber portion, when external disturbances propagate to the sensing fiber, local abrupt changes occur in the power spectra of both the OTDR and MZIS modules. Comparing the power spectra of the two devices at this point with those of the OTDR and MZIS during normal superconductor operation reveals significant differences, indicating a quench failure at that location. The quench detection system then issues a trigger signal, activating the energy release device in the subsequent superconducting protection system to complete the quench protection.

[0077] The OTDR module of this invention introduces an interference section different from that of traditional OTDR devices. This significantly improves the dynamic range of the OTDR, which was originally limited by receiver sensitivity, thus greatly increasing the measurement distance. Furthermore, this invention allows for the replacement of appropriate components according to specific needs. Utilizing distributed fiber optic sensing technology, it can monitor the temperature distribution of the entire conductor, enabling the system to operate continuously throughout the entire operation of the high-temperature superconductor. It is not damaged by short-term quench loss and allows for repeated online monitoring of the device.

[0078] This invention simultaneously collects both the forward-propagating waveguide light and the backscattered Rayleigh light propagating in an optical fiber to sense the same quench phenomenon, further improving the accuracy and speed of quench monitoring while reducing costs. When applied to online monitoring of superconducting quench, the MZIS module can quickly sense disturbances, thus detecting quench early to prevent device burnout; while the OTDR module can locate the fault after a certain delay, obtaining information about the fault point and providing guidance for maintenance and design optimization. The two modules share some components and perform real-time monitoring of the same superconductor, improving the reliability of quench detection to a certain extent while also saving costs.

[0079] Furthermore, since the quench propagation speed in high-temperature superconducting materials is several orders of magnitude lower than that in low-temperature superconducting materials, existing voltage methods cannot promptly reflect the initial state of quench in long-distance high-temperature superconducting quench monitoring. However, the distributed fiber optic sensing technology employed in this invention can sense external disturbances and characterize them in conjunction with other related equipment. Therefore, this invention utilizes distributed fiber optic sensing technology for online monitoring of disturbances such as temperature rise and deformation caused by superconducting quench. Distributed fiber optic sensing not only allows for continuous detection of temperature distribution at various locations within the superconductor but is also unaffected by harsh electromagnetic environments. In summary, this invention, employing distributed fiber optics, compared to traditional voltage-based quench detection methods, not only operates in harsh electromagnetic environments with monitoring performance unaffected by electromagnetic field disturbances but is also suitable for long-distance high-temperature superconducting quench monitoring and can be applied to the online detection of other external disturbances.

[0080] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0081] Those skilled in the art will understand that, in addition to implementing the system, apparatus, and their modules provided by this invention in purely computer-readable program code, the same program can be implemented in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers by logically programming the method steps. Therefore, the system, apparatus, and their modules provided by this invention can be considered a hardware component, and the modules included therein for implementing various programs can also be considered structures within the hardware component; alternatively, modules for implementing various functions can be considered both software programs implementing the method and structures within the hardware component.

[0082] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A superconducting quench monitoring system, characterized by, The module comprises a Mach-Zehnder interferometer module and an optical time domain reflectometer module; The Mach-Zehnder interferometer module and the optical time domain reflectometer module have a common component; The Mach-Zehnder interferometer module and the optical time domain reflectometer module can simultaneously monitor external disturbances in real time; The common component comprises a laser (1), an electro-optic modulator (2), a first beam splitter (3), a circulator (4), a sensing optical fiber (5), a reference optical fiber (6), and a second beam splitter (7); The laser (1), the electro-optic modulator (2), and the first beam splitter (3) are arranged in sequence, the first beam splitter (3) divides a first light signal into the circulator (4), and the circulator (4) is connected to one end of the sensing optical fiber (5); A second light signal outlet of the first beam splitter (3) is connected to the second beam splitter (7) through the reference optical fiber (6), and a first outlet of the second beam splitter (7) is connected to the reference optical fiber (6); The optical time domain reflectometer module further comprises a first polarization beam splitter (8), a second polarization beam splitter (9), a first compensator (10), a first polarization controller (11), a first coupler (12), a second coupler (13), a first balanced photodetector (14), a second balanced photodetector (15), and a first data acquisition and processing system (16); The circulator (4) transmits the light signal to the first polarization beam splitter (8), and the first polarization beam splitter (8) divides the light into first P-polarized light and first S-polarized light; The second outlet of the second beam splitter (7) divides the light signal into the first polarization controller (11) and the first compensator (10) in sequence, and then the light signal reaches the second polarization beam splitter (9), and the second polarization beam splitter (9) divides the light into second P-polarized light and second S-polarized light; The first P-polarized light and the second P-polarized light are coupled in the first coupler (12), and then pass through the first balanced photodetector (14) to reach the first data acquisition and processing system (16); The first S-polarized light and the second S-polarized light are coupled in the first coupler (12), and then pass through the second balanced photodetector (15) to reach the first data acquisition and processing system (16); The Mach-Zehnder interferometer module further comprises a second polarization controller (17), a second compensator (18), a third polarization beam splitter (19), a fourth polarization beam splitter (20), a third coupler (21), a fourth coupler (22), a third balanced photodetector (23), a fourth balanced photodetector (24), and a second data acquisition system (25); The other end of the sensing optical fiber (5) is connected to the third polarization beam splitter (19), and the third polarization beam splitter (19) divides the light into third P-polarized light and third S-polarized light; The first outlet of the second beam splitter (7), the second polarization controller (17), the second compensator (18), and the fourth polarization beam splitter (20) are connected in sequence through the reference optical fiber (6).

2. The superconducting quench monitoring system of claim 1, wherein, The sensing optical fiber (5) is provided with a superconducting strip connection surface.

3. The superconducting quench monitoring system of claim 2, wherein, The superconducting tape connecting surface is connected with the external superconducting tape through epoxy resin glue.

4. The superconducting quench monitoring system of claim 1, wherein, The second beam splitter (7) has a splitting ratio of 1:

99.

5. The superconducting quench monitoring system of claim 1, wherein, The first beam splitter (3) is a 3dB beam splitter.

6. The superconducting quench monitoring system of claim 1, wherein, The sensing optical fiber (5) is a distributed optical fiber.

7. A quench monitoring method using the superconducting quench monitoring system of any one of claims 1-6, further comprising the following steps: Step 1: the laser (1) emits laser light, which is modulated into pulsed light by an electro-optical modulator, and then enters the first beam splitter (3), which splits the light into two beams with equal power, which are the probe light and the reference light, respectively; Step 2: the probe light enters the sensing optical fiber (5) through the circulator (4), and the backscattered Rayleigh scattering light generated in the sensing optical fiber (5) enters the first polarization beam splitter (8) through the circulator (4) and is split into P and S polarizations; Step 3: the light entering the reference optical fiber (6) is split into strong and weak beams by the second beam splitter (7); The weak beam is introduced into the first polarization controller (11), and then passes through the first compensator (10) to reach the second polarization beam splitter (9), which splits the light into P and S polarizations, which are then coupled and interfered in the second coupler (13) and the first coupler (12), respectively; Step 4: the optical signal emitted by the first coupler (12) passes through the first balanced photodetector (14) and enters the first data acquisition and processing system (16); The optical signal emitted by the second coupler (13) passes through the second balanced photodetector (15) and enters the first data acquisition and processing system (16); The image of the OTDR is obtained using the first data acquisition and processing system (16); Step 5: the light waveguide propagating forward in the sensing optical fiber (5) is split into P and S polarizations by the third polarization beam splitter (19), and the strong light split from the reference optical fiber (6) by the second beam splitter (7) passes through the second polarization controller (17) and the second compensator (18) to enter the fourth polarization beam splitter (20) and be split into P and S polarizations; Step 6: the corresponding polarization state lights generated by the third polarization beam splitter (19) and the fourth polarization beam splitter (20) are coupled and interfered in the third coupler (21) and the fourth coupler (22), respectively; Step 7: the optical signal emitted by the third coupler (21) passes through the third balanced photodetector (23) and enters the second data acquisition system (25); The optical signal emitted by the fourth coupler (22) passes through the fourth balanced photodetector (24) and enters the first data acquisition second data acquisition system (25); The image of the MZIS is obtained using the second data acquisition system (25).

Images