A current measurement device and current measurement method based on silicon carbide spin defects

Abstract

The present invention discloses a current measuring device and a current measuring method based on silicon carbide spin defects. The device of the present invention has a simple structure and relatively low cost, and is very easy to promote and use. The present invention adopts a dual sensor structure for differential detection, which effectively avoids the influence of environmental magnetic field noise and greatly improves the measurement sensitivity. The detection sensitivity of the device of the present invention only depends on the concentration of silicon carbide spin defects, the density of excitation light and the fluorescence collection efficiency, and the sensitivity of magnetic field / current measurement can be further improved by optimizing the concentration and spin properties of silicon carbide spin defects, thereby broadening the space for improving detection accuracy. The present invention integrates silicon carbide and optical fiber into one, does not rely on a confocal optical path system, and uses optical fiber only for the transmission of excitation light and fluorescence. Its shape and length have little effect on the test results, and is very convenient to use.

Description

Technical Field

[0001] The present invention relates to the technical field of current sensors, and in particular to a current measuring device and a current measuring method based on silicon carbide spin defects. Background Art

[0002] Non-contact current sensors have the advantages of high safety, wide application range, easy installation and maintenance, strong anti-interference ability, etc. They perform well in various complex environments and are currently widely used. Non-contact current measurement converts current measurement into magnetic field measurement by utilizing the magnetic effect of current. The accuracy of magnetic field measurement determines the accuracy of current measurement.

[0003] At present, current sensors based on magnetic effect include: current transformer, Hall current sensor, fluxgate current sensor, giant magnetoresistance current sensor, fiber optic current sensor, etc.

[0004] Among them, the current transformer (such as the invention application with publication number CN118824712A) is based on the principle of electromagnetic induction, and converts large current into small current through a closed iron core and winding; the Hall current sensor (such as the invention application with publication number CN118884013A) is divided into open-loop and closed-loop types, the open-loop type adopts the Hall direct release principle, and the closed-loop type adopts the magnetic balance principle; the fluxgate current sensor (such as the invention application with publication number CN118884027A) measures the weak magnetic field by utilizing the saturation excitation phenomenon of the high permeability magnetic core in the alternating magnetic field, thereby indirectly measuring the current; the giant magnetoresistance current sensor (such as the invention application with publication number CN103616550A) is based on the giant magnetoresistance effect, that is, the resistivity of the magnetic material changes significantly under the action of the magnetic field; the optical fiber current sensor uses the Faraday magneto-optical effect to measure the magnetic field generated by the current through the optical fiber medium, rotate the angle of the polarized light, and thus measure the current.

[0005] However, the above current sensors also have shortcomings in practical applications, such as high manufacturing costs, sensitivity to magnetic field interference, and susceptibility to environmental influences. In particular, the physical properties of the optical fiber in the optical fiber current sensor, such as length and shape, also have a huge impact on current detection. These factors limit the stability and detection accuracy of the current sensor during use.

[0006] In recent years, research on spin defects in solid-state spin systems such as diamond and silicon carbide has received widespread attention, especially their achievements in the field of quantum sensing, which have achieved μT or even nT magnetic field sensing sensitivity using optical detection magnetic resonance (ODMR) spectroscopy technology. Summary of the invention

[0007] In view of the above-mentioned deficiencies in the prior art, the present invention provides a current measuring device and a current measuring method based on silicon carbide spin defects.

[0008] The present invention first provides a current measuring device based on silicon carbide spin defects, comprising:

[0009] Two silicon carbide optical fiber sensor probes, each of which includes an optical fiber and a sensor disposed on an end face of one end of the optical fiber, wherein the sensor is a piece of silicon carbide, and the silicon carbide contains spin defects; during detection, the two silicon carbide optical fiber sensor probes are respectively extended into the vicinity of the current-carrying conductor to be detected and are at an equal distance from the surface of the current-carrying conductor to be detected;

[0010] A microwave unit, comprising a microwave source for generating microwaves and a microwave antenna arranged around the periphery of one end of the optical fiber where the sensor is arranged, and for transmitting a microwave signal to the sensor, wherein the microwave signal is used to drive the silicon carbide spin defect;

[0011] A laser unit, comprising a laser, for inputting excitation light into the optical fibers in the two silicon carbide optical fiber sensor probes, wherein the excitation light is used to excite the sensors;

[0012] Two static magnets arranged in pairs, the two static magnets are arranged near the two silicon carbide optical fiber sensor probes, the magnetic field direction generated by the static magnets is parallel to the c-axis direction of the silicon carbide crystal of the sensor, and is used to split the spin state energy level of the silicon carbide spin defect;

[0013] The detection unit includes two photodetectors and a phase-locked amplifier. The two photodetectors are used to respectively detect the reflected fluorescence generated after the sensor spin defect in one of the silicon carbide optical fiber sensor probes is excited by the excitation light. The phase-locked amplifier is used to process and analyze the reflected fluorescence signals detected by the two photodetectors.

[0014] Preferably, the insulating coating of the optical fiber is removed at one end where the sensor is provided to form an optical fiber tip with the core exposed, and the sensor is provided on the end face of the optical fiber tip; the microwave antenna is provided around the periphery of the optical fiber tip. The sensor can be bonded to the end face of the optical fiber by ultraviolet curing adhesive.

[0015] The microwave antenna may use a copper coil. Preferably, the laser unit includes a beam splitter and two dichroic mirrors, the laser is one, and the excitation light emitted by the laser is split into two beams by the beam splitter and enters the optical fiber after passing through the dichroic mirrors. When the beam splitter splits the excitation light into two beams and each is incident on the dichroic mirror, if required by the design, a reflector may be provided to reflect the excitation light to change the incident direction of the excitation light so that the positions of the components can be arranged more reasonably.

[0016] More preferably, the photodetector is located on a side of the dichroic mirror away from the silicon carbide optical fiber sensor probe.

[0017] During detection, the reflected fluorescence generated by the sensor returns to the dichroic mirror along the optical fiber together with the excitation light, wherein the excitation light is filtered by the dichroic mirror and the reflected fluorescence is detected by the photodetector through the dichroic mirror.

[0018] The static magnet may be a neodymium magnet. The static magnet is used to split the spin state energy level of the silicon carbide spin defect, and the resonance frequency of the ODMR spectrum can be observed more clearly.

[0019] Preferably, the optical fiber is provided with an optical fiber coupler at one end away from the sensor.

[0020] Preferably, to ensure milliampere-level measurement accuracy, the spin defect concentration of the sensor is not less than 5 ppm. The spin defect concentration determines the sensitivity of the detection, and the higher the spin defect concentration, the higher the sensitivity.

[0021] The present invention also provides a current measurement method based on silicon carbide spin defects. Using the current measurement device based on silicon carbide spin defects, the current measurement method comprises the following steps:

[0022] Two silicon carbide optical fiber sensor probes are respectively extended near the current-carrying conductor to be detected, the microwave source generates microwaves and transmits microwave signals to the sensor through a microwave antenna, and the microwave signals are used to drive silicon carbide spin defects;

[0023] The laser inputs excitation light to the two optical fibers to excite the sensors. The spin defects in silicon carbide are excited by the excitation light to generate reflected fluorescence. The two photodetectors each detect the reflected fluorescence generated by one sensor and transmit the detected data to the phase-locked amplifier, which processes and analyzes the detected data.

[0024] Preferably, the microwave source generates microwaves of different frequencies to perform microwave frequency scanning on the sensor, the two photodetectors detect the intensity of reflected fluorescence generated by the two sensors at different microwave frequencies, the phase-locked amplifier processes and analyzes the detected data to obtain an amplitude-modulated light detection magnetic resonance spectrum, and the light detection magnetic resonance frequency is obtained by fitting; then, the light detection magnetic resonance spectra corresponding to the two silicon carbide optical fiber sensor probes are differentially processed to calculate the magnetic field around the current-carrying conductor to be detected and the corresponding current magnitude.

[0025] The method for differential processing of optical detection magnetic resonance (ODMR) spectrum is as follows:

[0026] Under the magnetic field applied by a static magnet, the ODMR spectrum of silicon carbide will show two obvious microwave resonance frequencies, which are recorded as low resonance frequency and low resonance frequency. and high resonant frequency , the difference of resonance frequency is calculated by subtracting the two, that is, The magnitude of the static magnetic field is ,according to The gyromagnetic ratio of the SiC spin defect can be determined ( ).

[0027] When the conductor to be tested is energized, one of the sensors (defined as the first sensor) measures the sum of the magnetic field generated by the energized conductor to be tested and the external magnetic field (i.e., the magnetic field other than the magnetic field generated by the energized conductor), and the other sensor (defined as the second sensor) measures the difference between the magnetic field generated by the energized conductor and the external magnetic field:

[0028] ,

[0029] ,

[0030] ,

[0031] in, and are the resonance frequency differences of the first sensor and the second sensor respectively; considering that the ambient magnetic field noise around the first sensor and the second sensor is slightly different, and They represent the magnitude of the external magnetic field around the first sensor and the second sensor respectively, and there is a fixed difference between them, namely 2 ; is the magnetic field generated by the conductor with current. and The difference can be calculated ; Under power-on condition, by and Differential processing can effectively eliminate the influence of the external magnetic field, and thus accurately obtain the magnetic field and corresponding current generated by the current-carrying conductor.

[0032] Compared with the prior art, the advantages of the present invention are:

[0033] The device of the present invention has a simple structure and relatively low cost, and is very easy to promote and use. The present invention adopts a dual sensor structure for differential detection, which effectively avoids the influence of environmental magnetic field noise and greatly improves the measurement sensitivity. The detection sensitivity of the device of the present invention only depends on the concentration of silicon carbide spin defects, the density of excitation light and the fluorescence collection efficiency, and the sensitivity of magnetic field / current measurement can be further improved by optimizing the concentration and spin properties of silicon carbide spin defects, thereby broadening the space for improving detection accuracy. The present invention integrates silicon carbide and optical fiber into one, does not rely on a confocal optical path system, and uses optical fiber only for the transmission of excitation light and fluorescence. Its shape and length have little effect on the test results, and is very convenient to use. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 Schematic diagram of the structure of the current measuring device of the present invention.

[0035] Figure 2 The figure is a schematic diagram of the structure of two sensors in the present invention, namely silicon carbide optical fiber sensor probes.

[0036] Figure numerals: 1 - laser, 2 - beam splitter, 3 - mirror, 4 / 5 - dichroic mirror, 6 / 7 - fiber coupler, 8 / 9 - optical fiber, 10 / 11 - photodetector, 12 / 13 - microwave antenna, 14 - microwave source, 15 - phase-locked amplifier, 16 - computer, 17 / 18 - static magnet, 19 - current-carrying conductor, 20 / 21 - sensor, 22 / 23 - optical fiber tip. DETAILED DESCRIPTION

[0037] The following is a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the protection scope of the present invention.

[0038] like Figure 1~Figure 2 As shown, a current measurement device based on silicon carbide spin defects includes two silicon carbide optical fiber sensor probes, a microwave unit, a laser unit and a detection unit.

[0039] Each of the two silicon carbide optical fiber sensor probes includes an optical fiber (optical fiber 8, optical fiber 9) and a sensor (sensor 20, sensor 21) disposed on the end surface of one end of the optical fiber. Each sensor is a piece of silicon carbide, which contains spin defects, and the spin defect concentration of silicon carbide is not less than 5ppm. During detection, the two silicon carbide optical fiber sensor probes are respectively extended to the vicinity of the current-carrying conductor to be detected and are at an equal distance from the surface of the current-carrying conductor to be detected.

[0040] The microwave unit includes a microwave source 14 for generating microwaves and a microwave antenna (microwave antenna 12, microwave antenna 13) arranged around the periphery of the end of the optical fiber where the sensor is arranged and used to transmit microwave signals to the sensor. The microwave signal is used to drive the spin defects of silicon carbide. The optical fiber is provided with a sensor at one end by removing the insulating skin to form an optical fiber tip (optical fiber tip 22, optical fiber tip 23) with the core exposed. The sensor is arranged on the end face of the optical fiber tip; the microwave antenna is arranged around the periphery of the optical fiber tip. The carbon sensor can be bonded to the end face of the optical fiber by UV curing glue.

[0041] One end of the optical fiber 8 has an optical fiber tip 22, on the end surface of which a sensor 20 is provided, and a microwave antenna 12 is provided around the outer periphery of the optical fiber tip 22. One end of the optical fiber 9 has an optical fiber tip 23, on the end surface of which a sensor 21 is provided, and a microwave antenna 13 is provided around the outer periphery of the optical fiber tip 23. A copper coil can be used as the microwave antenna.

[0042] The laser unit comprises a laser 1, which is used to input excitation light into the optical fibers in the two silicon carbide optical fiber sensor probes, and the excitation light is used to excite silicon carbide.

[0043] The laser unit includes a beam splitter 2 and two dichroic mirrors (dichroic mirror 4, dichroic mirror 5). The laser 1 is one. The excitation light emitted by the laser 1 is divided into two beams by the beam splitter 2. One beam is reflected by the reflector 3 and then enters the optical fiber 8 after passing through the dichroic mirror 4. The other beam enters the optical fiber 9 after passing through the dichroic mirror 5.

[0044] The optical fiber is provided with an optical fiber coupler at one end away from the sensor. Among them, an optical fiber 8 is provided with an optical fiber coupler 6 at one end, and an optical fiber 9 is provided with an optical fiber coupler 7 at one end.

[0045] The detection unit includes two photodetectors (photodetector 10, photodetector 11) and a phase-locked amplifier 15. The two photodetectors are respectively located on the side of the dichroic mirror on the corresponding side away from the silicon carbide fiber sensor probe. The two photodetectors are used to respectively detect the reflected fluorescence generated by the silicon carbide spin defect in one of the silicon carbide fiber sensor probes after being excited by the excitation light. Among them, the photodetector 10 is used to detect the reflected fluorescence generated by the sensor 20, and the photodetector 11 is used to detect the reflected fluorescence generated by the sensor 21. The phase-locked amplifier 15 is used to process and analyze the reflected fluorescence signals detected by the two photodetectors.

[0046] The current measurement device based on silicon carbide spin defects in the present application also includes two static magnets (static magnet 17, static magnet 18) arranged in pairs. The two static magnets are arranged near two silicon carbide optical fiber sensor probes. The direction of the magnetic field generated by the static magnets is parallel to the c-axis direction of the silicon carbide crystal, and is used to split the spin state energy level of the silicon carbide spin defect. The static magnet can be a neodymium magnet. Through the setting of the static magnet, it is used to split the spin state energy level of the silicon carbide spin defect, and the resonant frequency of the ODMR spectrum can be observed more clearly.

[0047] The current measurement device based on silicon carbide spin defects of the present application also includes a computer 16, which is used to operate the control system. The computer 16 is signal-connected to the microwave source 14 and the phase-locked amplifier 15 respectively, and is used to control the operation of the microwave source 14 and the phase-locked amplifier 15, and at the same time receive data from the phase-locked amplifier 15 for result processing and analysis.

[0048] The present invention also provides a current measurement method based on silicon carbide spin defects. Using the current measurement device based on silicon carbide spin defects of the present invention, the current measurement method comprises the following steps:

[0049] Two silicon carbide optical fiber sensor probes are respectively inserted near the current-carrying conductor 19 to be detected, and the microwave source 14 generates microwaves and transmits the microwave signals to the two sensors through two microwave antennas. The microwave signals are used to drive the silicon carbide spin defects.

[0050] Laser 1 emits excitation light, and the wavelength of the excitation light can be selected according to the type of spin defect. For example, the optimal excitation wavelength of silicon vacancy is 785nm, and the optimal excitation wavelength of divacancy is 920nm. In this embodiment, the excitation wavelength is 721nm. The excitation light is divided into two by beam splitter 2, one of which is reflected by beam splitter 2 and dichroic mirror 5, and then enters optical fiber 9 through fiber coupler 7, and finally enters sensor 21; the other excitation light passes through beam splitter 2 and is reflected by reflector 3 and dichroic mirror 4, and then enters optical fiber 8 through a fiber coupler 6, and finally enters sensor 20. After being irradiated by the excitation light, the silicon carbide spin defect generates reflected fluorescence, and the reflected fluorescence and the excitation light are both returned along the optical fiber. After passing through the dichroic mirror, the excitation light is filtered, and only the fluorescence signal is transmitted and enters the photodetector. The photodetector can realize the detection of weak fluorescence signals. Photodetector 10 and photodetector 11 detect the fluorescence signals of spin defects of sensor 20 and sensor 21 respectively, and transmit the collected data to phase-locked amplifier 15 for processing and analysis.

[0051] The microwave source 14 generates microwaves of different frequencies to perform microwave frequency scanning on the two sensors. The two photoelectric detectors detect the intensity of the reflected fluorescence generated by the two sensors at different microwave frequencies. The phase-locked amplifier 15 processes and analyzes the detected data to obtain an amplitude-modulated light detection magnetic resonance spectrum, and the light detection magnetic resonance frequency is obtained by fitting. The light detection magnetic resonance spectra corresponding to the two silicon carbide optical fiber sensor probes are then differentially processed to calculate the magnetic field around the current-carrying conductor 19 to be detected and the corresponding current size.

[0052] The two sensors contain a high concentration of spin defects. In one embodiment, the silicon carbide used as the sensor can use 4H crystals, and the spin defects are produced by electron irradiation, followed by high-temperature vacuum annealing at 600 degrees Celsius and immediate thermal quenching, and the spin defect concentration is about 5 ppm. Then, two block samples of the same size of 2 mm × 2 mm × 1 mm are cut from the same silicon carbide sample, and they are bonded to the end faces of optical fibers 8 and 9 by UV-curing glue. The optical fiber is a multimode optical fiber with a core diameter of 62.5 μm and an NA of 0.275.

[0053] The fluorescence intensity of the two silicon carbide optical fiber sensor probes at different microwave frequencies is recorded by the photodetector 10, the photodetector 11 and the phase-locked amplifier 15 to obtain the amplitude modulated ODMR, and the resonance frequency of the ODMR is obtained by fitting. Then, the ODMR spectra of the sensor 21 and the sensor 20 are differentially processed, and the magnetic field around the current-carrying conductor 19 and the corresponding current magnitude can be accurately calculated.

[0054] The method of ODMR spectrum difference processing is as follows:

[0055] Under the magnetic field applied by a static magnet, the ODMR spectrum of silicon carbide will show two obvious microwave resonance frequencies, which are recorded as low resonance frequency and low resonance frequency. and high resonant frequency , the difference of resonance frequency is calculated by subtracting the two, that is, The magnitude of the static magnetic field is ,according to The gyromagnetic ratio of the spin defects in SiC can be determined ( ).

[0056] When the conductor to be measured is energized, sensor 21 (defined as the first sensor) measures the sum of the magnetic field generated by the energized conductor and the external magnetic field, while sensor 20 (defined as the second sensor) measures the difference between the magnetic field generated by the energized conductor and the external magnetic field:

[0057] ,

[0058] ,

[0059] ,

[0060] in, and are the resonance frequency differences of the first sensor and the second sensor respectively; considering that the ambient magnetic field noise around the first sensor and the second sensor is slightly different, and They represent the magnitude of the external magnetic field around the first sensor and the second sensor respectively, and there is a fixed difference between them, namely 2 ; is the magnetic field generated by the conductor with current. and The difference can be calculated ; Under power-on condition, by and Differential processing can effectively eliminate the influence of the external magnetic field, and thus accurately obtain the magnetic field and corresponding current generated by the current-carrying conductor.

[0061] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A current measuring device based on silicon carbide spin defects, characterized in that: include: Two silicon carbide optical fiber sensor probes, each of which includes an optical fiber and a sensor disposed on an end face of one end of the optical fiber, wherein the sensor is a piece of silicon carbide, and the silicon carbide contains spin defects; during detection, the two silicon carbide optical fiber sensor probes are respectively extended into the two sides of the current-carrying conductor to be detected and are at an equal distance from the surface of the current-carrying conductor to be detected; A microwave unit, comprising a microwave source for generating microwaves and a microwave antenna arranged around the periphery of one end of the optical fiber where the sensor is arranged, and for transmitting a microwave signal to the sensor, wherein the microwave signal is used to drive the silicon carbide spin defect; A laser unit, comprising a laser, for inputting excitation light into the optical fibers in the two silicon carbide optical fiber sensor probes, wherein the excitation light is used to excite the sensors; Two static magnets arranged in pairs, the two static magnets are arranged near the two silicon carbide optical fiber sensor probes, the magnetic field direction generated by the static magnets is parallel to the c-axis direction of the silicon carbide crystal of the sensor, and is used to split the spin state energy level of the silicon carbide spin defect; A detection unit, comprising two photodetectors and a lock-in amplifier, wherein the two photodetectors are used to respectively detect reflected fluorescence generated after the sensor spin defect in one of the silicon carbide optical fiber sensor probes is excited by the excitation light, and the lock-in amplifier is used to process and analyze the reflected fluorescence signals detected by the two photodetectors; The microwave source generates microwaves of different frequencies to perform microwave frequency scanning on the sensor, the two photoelectric detectors detect the intensity of the reflected fluorescence generated by the two sensors at different microwave frequencies, the phase-locked amplifier processes and analyzes the detected data to obtain an amplitude-modulated light detection magnetic resonance spectrum, and the light detection magnetic resonance frequency is obtained by fitting; the light detection magnetic resonance spectra corresponding to the two silicon carbide optical fiber sensor probes are then differentially processed to calculate the magnetic field around the current-carrying conductor to be detected and the corresponding current magnitude; The method for differential processing of optical detection magnetic resonance spectrum is as follows: Under the magnetic field applied by a static magnet, the optical detection magnetic resonance spectrum of silicon carbide exhibits two wave resonance frequencies, which are denoted as the low resonance frequency and high resonant frequency , the resonance frequency difference ; The magnitude of the static magnetic field generated by the static magnet is recorded as ,according to Determining the gyromagnetic ratio of spin defects in silicon carbide ; When the conductor to be tested is energized, one sensor measures the sum of the magnetic field generated by the conductor to be tested and the external magnetic field, and the other sensor measures the difference between the magnetic field generated by the conductor and the external magnetic field: ， ， ， in, and are the resonance frequency differences of the two sensors respectively; considering that the ambient magnetic field noise around the two sensors is slightly different, and They represent the magnitude of the external magnetic field around the second sensor, and there is a fixed difference between them, namely 2 ; is the magnetic field generated by the energized conductor to be tested; when no power is supplied, the measured and Calculate the difference ; Under power-on condition, by and Differential processing eliminates the influence of the external magnetic field and obtains the magnetic field and corresponding current generated by the current-carrying conductor.

2. The current measurement device based on silicon carbide spin defects according to claim 1, characterized in that: The insulating skin of the optical fiber is removed at one end where the sensor is provided to form an optical fiber tip with a bare core, and the sensor is provided on the end face of the optical fiber tip; The microwave antenna is disposed around the outer circumference of the tip of the optical fiber.

3. The current measurement device based on silicon carbide spin defects according to claim 1, characterized in that: The laser unit comprises a beam splitter and two dichroic mirrors. There is one laser. The excitation light emitted by the laser is split into two beams by the beam splitter and enters the optical fiber after passing through the dichroic mirrors respectively.

4. The current measurement device based on silicon carbide spin defects according to claim 3, characterized in that: The photodetector is located on a side of the dichroic mirror away from the silicon carbide optical fiber sensor probe. During detection, the reflected fluorescence generated by the sensor returns to the dichroic mirror along the optical fiber together with the excitation light, wherein the excitation light is filtered by the dichroic mirror and the reflected fluorescence is detected by the photodetector through the dichroic mirror.

5. The current measurement device based on silicon carbide spin defects according to claim 1, characterized in that: The optical fiber is provided with an optical fiber coupler at one end away from the sensor.

6. The current measurement device based on silicon carbide spin defects according to claim 1, characterized in that: The spin defect concentration of the sensor is not less than 5 ppm.

7. A current measurement method based on silicon carbide spin defects, characterized in that: Using the current measuring device based on silicon carbide spin defects according to any one of claims 1 to 6, the current measuring method comprises the following steps: Two silicon carbide optical fiber sensor probes are respectively extended near the current-carrying conductor to be detected, the microwave source generates microwaves and transmits microwave signals to the sensor through a microwave antenna, and the microwave signals are used to drive silicon carbide spin defects; The laser inputs excitation light to the two optical fibers to excite the sensors. The silicon carbide spin defects are excited by the excitation light to produce reflected fluorescence. The two photodetectors each detect the reflected fluorescence produced by a sensor and transmit the detected data to the phase-locked amplifier, which processes and analyzes the detected data.

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