Quantum current sensor and current measuring method

Abstract

The invention belongs to the technical field of current detection, and provides a quantum current sensor and a current measurement method, and the sensor comprises a passive probe, a laser source, a photoelectric detection module, a microwave modulation module, and a microwave processing module. The passive probe comprises a diamond structure with a spinning color center, the laser source generates a laser signal, the microwave modulation module generates a microwave signal and modulates the microwave signal to generate a microwave modulation signal, the laser signal and the microwave modulation signal are transmitted to the passive probe to generate a fluorescence signal, and the photoelectric detection module converts the fluorescence signal into an electric signal. And the microwave processing module demodulates the electric signal to generate a demodulation signal and regulates and controls the microwave modulation module, so that the frequency of the microwave signal is matched with the resonant frequency of the spin color center of the diamond structure. Through the modulation and demodulation process and the remote transmission and frequency regulation and control of the microwave signal, the noise filtering effect and the current dynamic measurement range are improved, and the high-voltage side signal transmission without power consumption and the passive measurement of the high-voltage side are realized.

Description

Technical Field

[0001] The present application relates to the technical field of current detection, and in particular to a quantum current sensor and a current measurement method. Background Art

[0002] Quantum technology has made breakthroughs in many fields in recent years, especially in sensing technology. Its unique quantum properties have enabled it to show unprecedented potential in precision measurement. Among them, electromagnetic measurement based on quantum sensing technology has the advantages of wide measurement range, high sensitivity, and non-contact measurement, which makes it show wide application potential in the automotive industry, medical health, power systems and other fields.

[0003] In the field of high-voltage power transmission, the detection of the stable operation of the power grid is crucial to safeguarding the national economy and people's livelihood. By non-contact measurement of the electromagnetic signal generated by the cable current, the operation status of the power grid can be analyzed and detected in real time without interfering with the operation of the power grid, which is of great significance for ensuring the stable operation and maintenance of the power grid. The current sensing technology based on diamond spin color centers has great application potential in the field of power grid detection due to its large dynamic range, high-precision measurement, strong stability, and adjustable spin state.

[0004] At present, current sensing devices based on diamond spin color centers are often based on confocal systems, involving large and bulky experimental equipment with complex structures, which limits the integration of sensors. In addition, the limited space of high-voltage power grids increases the difficulty of sensor installation. At the same time, due to the insulation of high-voltage power grids and the equipotential requirements for sensor installation, sensors installed on the power grid cannot be electrically connected to the ground, resulting in difficulty in powering sensors installed on the power grid.

[0005] Based on this, the present application provides a non-contact quantum current sensor and current measurement method to solve the above problems.

[0006] It should be noted that the above introduction to the technical background is only for the convenience of providing a clear and complete description of the technical solutions of the present application and for the convenience of understanding by those skilled in the art. It cannot be considered that the above technical solutions are well known to those skilled in the art simply because they are described in the background technology section of the present application. Summary of the invention

[0007] In view of the above-mentioned shortcomings of the prior art, the purpose of the present application is to provide a quantum current sensor and a current measurement method to solve the problems existing in the prior art, such as the difficulty in equipment installation and the difficulty in energy supply.

[0008] To achieve the above-mentioned and other related purposes, the present application provides a quantum current sensor, including a passive probe, a laser source, a photoelectric detection module, a microwave modulation module and a microwave processing module;

[0009] The laser source generates a laser signal of a preset wavelength and transmits it to the passive probe;

[0010] The microwave modulation module is used to generate a microwave signal, modulate the microwave signal to generate a microwave modulation signal, and send the microwave modulation signal to the passive probe;

[0011] The passive probe comprises a diamond structure having a spin color center and is spaced apart from the conductor to be tested. According to the laser signal and the microwave modulation signal, the diamond structure generates a fluorescence signal and transmits it to the photoelectric detection module;

[0012] The photoelectric detection module converts the fluorescent signal into an electrical signal and sends it to the microwave processing module;

[0013] The microwave processing module demodulates the electrical signal to generate a demodulation signal, and regulates the microwave modulation module according to the demodulation signal so that the frequency of the microwave signal matches the resonance frequency of the spin color center of the diamond structure.

[0014] Optionally, the passive probe further comprises a circuit board, a microwave interface, an optical interface and a microwave receiver;

[0015] The microwave receiver is connected to the microwave interface and is used to receive the microwave modulation signal, and the microwave modulation signal is transmitted to the circuit board via the microwave interface;

[0016] The diamond structure is located between the circuit board and the optical interface. The circuit board is provided with a microwave input unit on a side close to the diamond structure. The microwave input unit partially or completely covers the diamond structure. The microwave modulation signal forms a uniform microwave field on the surface of the diamond structure through the microwave input unit.

[0017] The optical interface is used to couple the laser signal to the surface of the diamond structure to excite the spin color center of the diamond structure, and the fluorescence signal is output to the passive probe via the optical interface.

[0018] Optionally, the quantum current sensor further comprises an optical transmission module, wherein the optical transmission module comprises a first optical transmission channel, a second optical transmission channel and an optical fiber circulator;

[0019] The fiber optic circulator has a first interface, a second interface and a third interface. The first interface is used to receive the laser signal emitted by the laser source. The second interface is connected to the passive probe via the first optical transmission channel to transmit the laser signal to the passive probe and receive the fluorescence signal from the passive probe. The third interface is connected to the photoelectric detection module via the second optical transmission channel.

[0020] Optionally, the quantum current sensor further includes a spectrometer, which is located between the laser source and the optical fiber circulator to separate a reference light signal from the laser signal. The optical transmission module further includes a third optical transmission channel, and the reference light signal is transmitted to the photoelectric detection module via the third optical transmission channel.

[0021] Optionally, the quantum current sensor further includes an optical filter, and the optical filter is arranged on the second optical transmission channel.

[0022] Optionally, the microwave modulation module includes a microwave generating unit, a microwave modulation unit and a microwave transmitter;

[0023] The microwave generating unit generates the microwave signal and sends it to the microwave modulating unit, wherein the frequency of the microwave signal is set to the resonance frequency of the spin color center of the diamond structure;

[0024] The microwave modulation unit modulates the frequency of the microwave signal according to a preset reference signal to generate the microwave modulation signal, sends the reference signal to the microwave processing module, and sends the microwave modulation signal to the microwave transmitter;

[0025] The microwave transmitter is used to transmit the microwave modulation signal.

[0026] Optionally, the microwave processing module includes a demodulation unit and a microwave control unit;

[0027] The demodulation unit is used to demodulate the electrical signal according to the reference signal to obtain a demodulated signal, and send the demodulated signal to the microwave control unit;

[0028] Based on the demodulation signal and a preset demodulation slope, the microwave control unit calculates a frequency offset, and regulates the microwave generating unit according to the frequency offset, so that the microwave generating unit generates a microwave signal that matches the resonance frequency of the spin color center of the diamond structure.

[0029] Optionally, the demodulation unit comprises a lock-in amplifier and a filter.

[0030] Optionally, the microwave modulation module includes a first microwave generating unit, a second microwave generating unit, a microwave modulation unit and a microwave transmitter, and the microwave processing module includes a first demodulation unit, a second demodulation unit and a microwave control unit;

[0031] The first microwave generating unit generates a first microwave signal, the microwave modulating unit modulates the first microwave signal to generate a first modulated signal, the second microwave generating unit generates a second microwave signal, the microwave modulating unit modulates the second microwave signal to form a second modulated signal, and the first modulated signal and the second modulated signal are transmitted to the passive connector via the microwave transmitter;

[0032] The first demodulation unit and the second demodulation unit are both connected to the photoelectric detection module to receive the electrical signal, the first demodulation unit demodulates the electrical signal to obtain a first demodulation signal, and sends the first demodulation signal to the microwave control unit, the second demodulation unit demodulates the electrical signal to obtain a second demodulation signal, and sends the second demodulation signal to the microwave control unit;

[0033] The resonant frequency of the diamond structure spin center includes a first resonant frequency and a second resonant frequency. The microwave control unit regulates the first microwave generating unit according to the first demodulation signal so that the frequency of the first microwave signal matches the first resonant frequency, and regulates the second microwave generating unit according to the second demodulation signal so that the frequency of the second microwave signal matches the second resonant frequency.

[0034] Optionally, there are multiple passive probes, and the multiple passive probes are distributed in an array to form a passive probe array.

[0035] Optionally, there are multiple passive probes, and the multiple passive probes are evenly surrounded by the outer circumference of the conductor to be tested.

[0036] The present application also provides a current measurement method, which uses any one of the quantum current sensors in the aforementioned embodiments to measure the current value of a conductor to be measured, comprising the following steps:

[0037] Arranging the passive probe of the quantum current sensor at a preset position;

[0038] modulating the microwave signal based on a preset reference signal to generate a microwave modulated signal;

[0039] Transmitting a laser signal of a preset wavelength and the microwave modulation signal to a passive probe to generate a fluorescence signal;

[0040] converting the fluorescent signal into an electrical signal;

[0041] Demodulating the electrical signal using the reference signal to obtain a demodulated signal;

[0042] Calculating a frequency offset according to the demodulated signal and a preset demodulation slope;

[0043] Regulating the microwave signal according to the frequency offset so that the frequency of the microwave signal matches the resonance frequency of the spin color center of the diamond structure;

[0044] The current value of the conductor to be measured is obtained by calculation according to the frequency of the microwave signal.

[0045] The quantum current sensor and current measurement method provided by the present application have at least the following beneficial effects:

[0046] On the first aspect, the quantum current sensor and current measurement method of the present application use a passive probe to achieve non-contact measurement of current, and there is no need to provide batteries or other power supply equipment on the high-voltage side where the conductor to be measured is located. The part with electrical power consumption is transferred to the low-voltage side, which reduces the difficulty of installation, improves the applicability of the equipment, and is more conducive to the promotion and use of the equipment.

[0047] On the second aspect, the quantum current sensor and current measurement method of the present application use an insulated optical transmission module to transmit optical signals, and use air to transmit microwave modulated signals, thereby achieving electrical insulation between the passive probe and the low-voltage side, and achieving long-distance transmission of optical signals and microwave signals, thereby achieving long-distance monitoring of the power grid status, reducing the difficulty of installation and use of the equipment, and improving the applicability of the equipment.

[0048] On the third aspect, the quantum current sensor and current measurement method of the present application, by setting a spectrometer and a filter to filter the laser noise, by modulating the microwave signal and demodulating the fluorescence signal, effectively improves the noise filtering effect of the equipment and improves the accuracy and reliability of the measurement results.

[0049] Fourthly, the quantum current sensor and current measurement method of the present application regulate the frequency of the microwave signal according to the demodulation signal so that the frequency of the microwave signal automatically tracks the resonance frequency of the spin center of the diamond structure, effectively expanding the dynamic measurement range of the current and improving the precision, accuracy and reliability of the measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0051] Figure 1 Shown is a schematic diagram of the structure of the quantum current sensor provided in Example 1 of the present application.

[0052] Figure 2 Shown is a schematic diagram of the relationship between the fluorescence signal intensity and the microwave signal frequency of the quantum current sensor provided in Example 1 of the present application.

[0053] Figure 3 Shown is a schematic diagram of the specific structure of the quantum current sensor provided in Example 1 of the present application.

[0054] Figure 4 Display as Figure 1 Schematic diagram of the structure of the passive probe in the quantum current sensor shown.

[0055] Figure 5 Display as Figure 1 The schematic diagram of the structure of the microwave processing module and the microwave modulation module in the quantum current sensor is shown.

[0056] Figure 6 It shows a schematic diagram of the relationship between the magnetic induction intensity and the current of the conductor to be measured obtained in the first embodiment of the present application.

[0057] Figure 7 Shown is a schematic diagram of the structure of the quantum current sensor provided in Example 2 of the present application.

[0058] Figure 8 Shown is a schematic structural diagram of a quantum current sensor provided in an optional embodiment of the third embodiment of the present application.

[0059] Fig. 9 Shown is a schematic structural diagram of a quantum current sensor provided in an optional embodiment of the fourth embodiment of the present application.

[0060] Fig.10 Shown is a flow chart of the current measurement method provided in Example 5 of the present application.

[0061] Reference numerals:

[0062] 10. Test wire; 11. Passive probe; 111. Circuit board; 1111. Microwave input unit; 112. Diamond structure; 113. Optical interface; 114. Microwave interface; 115. Microwave receiver; 101. First probe; 102. Second probe; 103. Third probe; 12. Laser source; 121. Spectrometer; 13. Photoelectric detection module; 131. Filter; 14. Microwave modulation module; 141. Microwave generating unit; 1411. First microwave generating unit Element; 1412, second microwave generating unit; 142, microwave modulation unit; 143, microwave transmitter; 15, microwave processing module; 151, demodulation unit; 1511, phase-locked amplifier; 1512, filter; 1501, first demodulation unit; 1502, second demodulation unit; 152, microwave control unit; 16, optical transmission module; 161, first optical transmission channel; 162, second optical transmission channel; 163, optical fiber circulator; 164, third optical transmission channel. DETAILED DESCRIPTION

[0063] In order to make the technical purpose, technical solution and technical effect of the present application clearer, the technical solution in the present application will be clearly and completely described in conjunction with the embodiments below. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0064] Therefore, the following detailed description of the embodiments of the present application is not intended to limit the scope of the present application for protection, but merely represents the selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work are within the scope of protection of the present application. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0065] In the description of the present application, it should be noted that the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "example", "specific example" or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the implementation or example are included in at least one implementation or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same implementation or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more implementations or examples in a suitable manner.

[0066] Embodiment 1

[0067] This embodiment provides a quantum current sensor, which is used to solve the problems of equipment power supply difficulties, installation and use difficulties in the prior art.

[0068] Reference Figure 1 The quantum current sensor of this embodiment includes a passive probe 11, a laser source 12, a photoelectric detection module 13, a microwave modulation module 14 and a microwave processing module 15.

[0069] Reference Figures 1 to 3 The passive probe 11 is spaced apart from the conductor 10 to be tested and is arranged in the area around the conductor 10 to be tested. Optionally, the distance between the passive probe and the conductor 10 to be tested is less than a first distance threshold. The passive probe 11 includes a diamond structure 112. The diamond structure 112 has a spin color center, which is an NV color center. The NV color center refers to a point defect formed when a nitrogen atom in a diamond replaces a carbon atom and combines with a neighboring hole to capture an electron. The NV color center can exhibit strong fluorescence under laser pumping. For example, under laser excitation with a wavelength of 532nm, the NV color center can emit fluorescence. At the same time, by radiating microwaves, the energy level distribution of the spin color center can be adjusted, thereby regulating the intensity of the emitted fluorescence. The electron spin resonance frequency of the spin color center is recorded as the resonance frequency f ± , the resonance frequency f of the spin color center ± Including the first resonant frequency f + and the second resonance frequency f - , and the resonant frequency f ± Satisfy the following formula:

[0070] f ± =D gs ±γB 0 (1)

[0071] Among them, D gs is the zero-field splitting of the quantum spin color center, γ is the magnetic gyro ratio of the quantum spin, B 0 is the magnetic induction intensity of the magnetic field induced by the quantum spin color center. When there is no external magnetic field, the spin energy levels corresponding to the first resonance frequency and the second resonance frequency are in a degenerate state. When the spin color center senses the external magnetic field, the first resonance frequency f + and the second resonance frequency f- are shifted by +γB 0 and -γB 0 When the applied microwave frequency is equal to the resonance frequency of the spin color center, under the excitation of continuous laser, a decreasing peak of the fluorescence intensity emitted by the spin color center can be observed, and then the magnetic induction intensity of the external magnetic field sensed by the spin color center can be obtained according to formula (1). Therefore, the fluorescence signal emitted by the spin color center can reflect the magnitude of the external magnetic field sensed by the spin color center.

[0072] The laser source 12 can generate a laser signal of a preset wavelength and transmit it to the passive probe 11 to excite the spin color center of the diamond structure 112, so that the self-selected color center of the diamond structure 112 can radiate fluorescence. Optionally, the preset wavelength can be, for example, 532nm, and the laser source 12 generates a laser signal of a wavelength of 532nm to irradiate the surface of the diamond structure 112 of the passive probe 11, so that the diamond structure 112 emits fluorescence.

[0073] The microwave modulation module 14 is used to generate a microwave signal, and modulate the microwave signal to generate a microwave modulation signal, and the microwave modulation module 14 transmits the microwave modulation signal to the passive probe 11. Under the action of the laser signal and the microwave modulation signal, the spin color center of the diamond structure 112 emits a fluorescence signal, and the microwave modulation signal can drive the energy level distribution of the spin color center, thereby realizing the regulation of the fluorescence signal. Specifically, the passive probe 11 can form a microwave field on the surface of its diamond structure 112 through the microwave modulation signal, thereby driving the energy level of the spin color center of the diamond structure 112, thereby realizing the regulation of the fluorescence signal intensity.

[0074] The photoelectric detection module 13 is connected to the wireless probe, and can receive the fluorescence signal emitted by the wireless probe and convert the fluorescence signal into an electrical signal. The photoelectric detection module 13 is also connected to the microwave processing module 15, and can transmit the electrical signal to the microwave processing module 15.

[0075] The microwave processing module 15 demodulates the received electrical signal to generate a demodulation signal, and optionally, the demodulation signal is a demodulation voltage. The microwave processing module 15 regulates the microwave modulation module 14 according to the demodulation signal, so that the frequency of the microwave signal generated by the microwave modulation module 14 matches the resonance frequency of the spin color center of the diamond structure 112, so that the frequency of the microwave signal can automatically track the resonance frequency of the spin color center of the diamond structure 112, thereby achieving the purpose of obtaining the magnetic field change of the conductor 10 to be tested through the frequency change.

[0076] When current flows through the wire 10 to be tested, a magnetic field is generated around the wire 10 to be tested. The magnetic field is detected by the passive probe 11 to obtain the magnitude of the magnetic field. The magnetic field induced by the wire 10 to be tested and the current in the wire 10 to be tested have the following relationship:

[0077] 2πRB=μ 0 I (2)

[0078] Wherein, B is the magnetic induction intensity of the external magnetic field sensed by the passive probe 11, R is the distance between the passive probe 11 and the wire 10 to be measured, I is the current of the wire 10 to be measured, μ 0According to the magnetic field size detected by the non-radial probe, the current of the conductor 10 to be measured can be calculated according to formula (2), thereby realizing non-contact measurement of the current of the conductor 10 to be measured.

[0079] In this embodiment, refer to Figure 3 and Figure 4 The passive probe 11 includes a circuit board 111 , a microwave interface 114 , an optical interface 113 and a microwave receiver 115 .

[0080] The microwave receiver 115 is connected to the microwave interface 114, and can receive the microwave modulation signal emitted by the microwave modulation module 14, and the microwave modulation signal is transmitted to the circuit board 111 via the microwave interface 114. Optionally, the microwave receiver 115 includes a receiving antenna, and the microwave modulation signal emitted by the microwave modulation module 14 is received by the receiving antenna; further, the receiving antenna is a directional antenna, such as a horn antenna, a parabolic antenna, etc., to increase the gain of the microwave receiver 115, thereby increasing the microwave power input to the passive probe 11.

[0081] In an optional embodiment, the microwave receiver 115 further includes a protective cover, which is sleeved around the periphery of the microwave receiver 115, for example, the protective cover is sleeved around the periphery of the receiving antenna of the microwave receiver 115. The protective cover can effectively prevent interference from external environments such as wind, rain, condensation, etc.

[0082] A microwave input unit 1111 is provided on one side of the circuit board 111 close to the diamond structure 112, and the microwave input unit 1111 partially or completely covers the diamond structure 112, so that the microwave modulated signal can be transmitted in the circuit board 111 and form a uniform microwave field on the surface of the diamond structure 112. The microwave field can be used to adjust the energy level of the spin color center of the diamond structure 112, thereby affecting the fluorescence intensity radiated by the spin color center.

[0083] In an optional embodiment, the microwave input unit 1111 includes a resonator and a microstrip line. The microwave modulated signal is transmitted in the microstrip line and generates a uniform microwave field of a specific frequency through the resonator, which effectively improves the measurement accuracy of the passive probe 11. The microstrip line has a larger bandwidth, which improves the measurement range of the passive probe 11.

[0084] The optical interface 113 is connected to the laser source 12 and is arranged on a side of the diamond structure 112 away from the circuit board 111, so that the diamond structure 112 is located between the optical interface 113 and the circuit board 111. The optical interface 113 is used to couple the laser signal and irradiate it to the surface of the diamond structure 112 to excite the spin color center of the diamond structure 112, and output the fluorescence signal radiated by the diamond structure 112 from the passive probe 11.

[0085] In this embodiment, the quantum current sensor further includes an optical transmission module 16 for transmitting optical signals such as laser signals and fluorescent signals. Optionally, the optical transmission module 16 is an optical fiber.

[0086] In an alternative embodiment, reference Figure 3 , the optical transmission module 16 includes a first optical transmission channel 161, a second optical transmission channel 162 and an optical fiber circulator 163. The optical fiber circulator 163 has a first interface, a second interface and a third interface. The first interface is used to receive the laser signal emitted by the laser source 12. The second interface is connected to the passive probe 11 via the first optical transmission channel 161. The laser signal enters the optical transmission module 16 through the first interface for transmission, and is transmitted to the passive probe 11 via the second interface and the first optical transmission channel 161. The fluorescent signal emitted by the passive probe 11 enters the optical transmission module 16 through the first optical transmission channel 161 for transmission. The third interface is connected to the photoelectric detection module 13 via the second optical transmission channel 162. The fluorescent signal is transmitted to the photoelectric detection module 13 via the first optical transmission channel 161, the second interface, the optical fiber circulator 163, the third interface, and the second optical transmission channel 162 in sequence. Optionally, the first optical transmission channel 161 and the second optical transmission channel 162 can be optical devices such as optical fibers and optical waveguides, and the present embodiment is not limited thereto.

[0087] In an alternative embodiment, reference Figure 3 The quantum current sensor also includes a spectrometer 121, which is disposed between the laser source 12 and the optical fiber circulator 163. The spectrometer 121 is used to separate a reference light signal from the laser signal. The optical transmission module 16 includes a third optical transmission channel 164. The reference light signal is transmitted to the photoelectric detection module 13 via the third optical transmission channel 164. The photoelectric detection module 13 can differentially amplify the reference light signal and the fluorescent signal, thereby eliminating the laser signal contained in the fluorescent signal, thereby achieving common-mode suppression of laser noise, achieving the purpose of optical signal noise reduction, and improving the accuracy of the measurement result. Optionally, the spectrometer 121 is a spectroscope, and the laser signal is transmitted to the optical transmission module 16 via the spectroscope. The spectroscope separates the reference light signal from the incident laser signal and transmits it to the photoelectric detection module 13 via the third optical transmission channel 164.

[0088] In an alternative embodiment, reference Figure 3 The quantum current sensor further includes an optical filter 131, which is disposed on the second optical transmission channel 162. The fluorescent signal emitted by the passive probe 11 is filtered by the optical filter 131 and then transmitted to the photoelectric detection module 13 to filter the laser noise. Optionally, the optical filter 131 may be, for example, a long-pass filter, which can effectively filter the laser noise in the fluorescent signal and improve the accuracy of the measurement result.

[0089] In this embodiment, refer to Figure 5The microwave modulation module 14 includes a microwave generating unit 141 , a microwave modulation unit 142 and a microwave transmitter 143 .

[0090] The microwave generating unit 141 is used to generate a microwave signal and transmit the microwave signal to the microwave modulation unit 142. Optionally, the microwave generating unit 141 can generate a microwave signal with a specific frequency, for example, the frequency of the microwave signal is set to the resonant frequency of the spin center of the diamond structure 112, and the microwave generating unit 141 is used to generate a microwave signal with a frequency of the resonant frequency.

[0091] The microwave modulation unit 142 is connected to the microwave generation unit 141, and is used to modulate the frequency of the microwave signal according to a preset reference signal to generate a microwave modulation signal, and transmit the reference signal to the microwave processing module 15, and transmit the microwave modulation signal to the microwave transmitter 143. Optionally, the preset reference signal is 2πtf mod , the frequency of the microwave modulation signal is f 0 ±f dev sin(2πtf mod ), where t is time, f 0 is the frequency of the microwave signal, denoted by f dev is the amplitude of the modulation frequency, the reference signal constitutes the phase of the modulation frequency, f mod is the preset reference change frequency.

[0092] The microwave transmitter 143 is connected to the microwave modulation unit 142, and is used to receive the microwave modulation signal and transmit the microwave modulation signal so that the microwave modulation signal is transmitted to the passive probe 11. Optionally, the microwave transmitter 143 includes a transmitting antenna, through which the microwave modulation signal is transmitted. Further, the transmitting antenna is a directional antenna, such as a horn antenna, a parabolic antenna, etc., to increase the microwave power transmitted to the passive probe 11.

[0093] In an optional embodiment, a protective cover is disposed around the microwave transmitter 143 , for example, the protective cover is disposed around the transmitting antenna to prevent the external environment from interfering with the microwave transmitter 143 .

[0094] In an optional embodiment, the microwave modulation module 14 also includes a microwave power amplifier, which is arranged between the microwave modulation unit 142 and the passive probe 11, and is used to amplify the microwave modulation signal to increase the microwave power of the microwave modulation signal received by the passive probe 11, thereby driving a larger number of spin color centers and improving the fluorescence contrast.

[0095] In this embodiment, refer to Figure 5The microwave processing module 15 includes a demodulation unit 151 and a microwave control unit 152. The demodulation unit 151 is connected to the microwave modulation unit 142 and the photoelectric detection module 13 respectively to receive the reference signal sent by the microwave modulation unit 142 and the electrical signal sent by the photoelectric detection module 13. According to the received reference signal, the demodulation unit 151 demodulates the electrical signal to obtain a demodulated signal, and sends the demodulated signal to the microwave control unit 152. Optionally, the demodulation unit 151 includes a lock-in amplifier 1511 and a filter 1512. The electrical signal and the reference signal are multiplied in the lock-in amplifier 1511 to obtain a frequency (f mod ±f mod ) and transmits the above signal to the filter 1512 to filter out the frequency 2f mod signal, thereby obtaining a demodulated signal with a frequency of zero, and further, the filter 1512 is a low-frequency filter.

[0096] The demodulation signal is a demodulation voltage. When the frequency of the microwave signal is equal to the resonance frequency of the spin center of the passive probe 11, the demodulation voltage is zero. When the magnetic field strength sensed by the passive probe 11 changes, the resonance frequency of the diamond structure 112 of the passive probe 11 changes accordingly, so that there is a frequency deviation between the frequency of the microwave signal and the current resonance frequency, and then the value of the demodulation voltage changes accordingly. Within a certain range, the demodulation voltage maintains a linear change relationship with the induced magnetic field. Therefore, the magnetic field strength sensed by the passive probe 11 can be reflected by the value of the demodulation voltage, and noise suppression is achieved, thereby improving the accuracy of the measurement result.

[0097] The microwave control unit 152 is connected to the demodulation unit 151 and the microwave modulation module 14 respectively to receive the demodulation signal and control the microwave modulation module 14 to generate a microwave signal. Based on the demodulation signal and the preset demodulation frequency, the microwave control unit 152 can calculate the frequency offset and regulate the microwave generating unit 141 according to the frequency offset so that the microwave generating unit 141 generates a microwave signal that matches the resonance frequency of the spin color center of the diamond structure 112. Specifically, when the frequency of the microwave signal is equal to the resonance frequency of the spin color center of the passive probe 11, the demodulated signal is zero. When the frequency of the microwave signal changes, within a certain range, the demodulated signal changes linearly with the frequency of the microwave signal, and the slope of the linear change of the demodulated signal with the frequency of the microwave signal is recorded as the demodulation slope k. When the magnetic field sensed by the passive probe 11 changes, the frequency offset Δf=ΔV / k of the microwave signal can be calculated according to the demodulation slope k and the demodulation signal change ΔV. According to the frequency offset, the microwave control unit 152 is used to control the microwave generating unit 141 so that the frequency of the generated microwave signal changes accordingly by Δf, thereby matching the frequency of the microwave signal with the resonance frequency of the spin color center of the passive probe 11, so that the value of the demodulated signal becomes zero again, thereby realizing the automatic tracking of the frequency of the microwave signal to the resonance frequency of the spin color center of the diamond structure 112, expanding the measurement range of the quantum current sensor, and making the quantum current sensor have extremely high use and promotion value.

[0098] In an optional embodiment, the microwave processing module 15 further includes a current output unit, which is used to calculate the current of the conductor 10 to be measured and output the current to the microwave processing module 15. Specifically, the current output unit is connected to the microwave control unit 152. According to the frequency of the microwave signal, the current output unit can calculate the current value of the conductor 10 to be measured using formula (1) and formula (2). Optionally, the quantum current sensor further includes an output module, which is connected to the microwave processing module 15 and is used to display the measured current value of the conductor 10 to be measured.

[0099] To verify the current measurement performance of the quantum current sensor of this embodiment, refer to Figure 6, the current in the wire 10 to be tested is increased from 0 to 150A. At the same time, according to the frequency of the microwave signal transmitted by the quantum current sensor to the passive probe 11, the measured value of the magnetic induction intensity at the location of the passive probe 11 is calculated using formula (1), and the reference value of the magnetic induction intensity at the location of the passive probe 11 is calculated using formula (2). The measured value of the magnetic induction intensity is compared with the reference value, which can reflect the quantum current sensor's ability to measure current. Specifically, when the current of the wire 10 to be tested is 150A, the measured value of the magnetic induction intensity is 410.5uT, and the maximum error point appears at the point corresponding to 50A, with an error of 0.53uT. It can be seen that the measurement error of the quantum current sensor is much less than 1%, which verifies that the quantum current sensor of this embodiment has excellent current measurement capability.

[0100] The quantum current sensor of this embodiment uses a passive probe 11 for non-contact measurement, and there is no need to install energy supply equipment on the high-voltage side of the conductor 10 to be measured, which reduces the difficulty of installation and is conducive to the promotion and use of quantum current sensors; the passive probe 11 can be remotely transmitted with the laser source 12 and the microwave modulation module 14, thereby realizing remote monitoring of the operation status of the power grid; the optical transmission module 16 is used to transmit optical signals, and the microwave modulation signal is transmitted through the air, avoiding the use of metal cables for transmission, realizing electrical insulation between the passive probe 11 and the low-voltage side of the equipment, and improving the applicability of the quantum current sensor; by The spectrometer 121 and the filter are provided to achieve effective filtering of laser noise, thereby improving the accuracy and precision of the measurement result; the microwave modulation unit 142 is used to modulate the microwave signal, and the demodulation unit 151 is used to demodulate the electrical signal. Through this modulation and demodulation method, the filtering effect of noise is further enhanced, and the accuracy of the measurement result is improved; based on the demodulation signal and the preset demodulation slope, the microwave control unit 152 is used to control the frequency of the microwave signal, thereby achieving automatic tracking of the frequency of the microwave signal to the resonance frequency of the spin color center of the diamond structure 112, thereby expanding the measurement range of the quantum current sensor.

[0101] Embodiment 2

[0102] This embodiment provides a quantum current sensor, which is basically the same as the first embodiment, wherein the similarities are not repeated here. The difference is that in the quantum current sensor of this embodiment, the microwave modulation module 14 may include multiple microwave generating units, and the microwave processing module 15 may include one or more demodulation units.

[0103] In an alternative embodiment, reference Figure 7The microwave modulation module 14 may include, for example, two microwave generating units, specifically, the microwave modulation module 14 includes a first microwave generating unit 1411, a second microwave generating unit 1412, a microwave modulation unit 142, and a microwave transmitter 143. The microwave processing module 15 may include, for example, two demodulation units, specifically, the microwave processing module 15 includes a first demodulation unit 1501, a second demodulation unit 1502, and a microwave control unit 152.

[0104] The microwave modulation signal includes a first modulation signal and a second modulation signal, and the microwave signal includes a first microwave signal and a second microwave signal. The first microwave generating unit 1411 is capable of generating a first microwave signal, and the microwave modulation unit 142 modulates the first microwave signal to generate a first modulation signal. Specifically, the frequency of the first microwave signal is modulated according to a preset reference signal to generate a first modulation signal, and the reference signal is sent to the microwave processing module 15. The second microwave generating unit 1412 is capable of generating a second microwave signal, and the microwave modulation unit 142 modulates the second microwave signal to form a second modulation signal. Specifically, the frequency of the second microwave signal is modulated according to a preset reference signal to generate a second modulation signal. The first microwave modulation signal and the second modulated microwave signal are transmitted to the passive connector via the microwave transmitter 143. Optionally, the spin color center of the diamond structure 112 in the passive probe 11 has a first resonant frequency and a second resonant frequency, the frequency of the first microwave signal is set to the first resonant frequency, and the frequency of the second microwave signal is set to the second resonant frequency.

[0105] The first demodulation unit 1501 and the second demodulation unit 1502 are both connected to the photoelectric detection module 13, and the photoelectric detection module 13 transmits the electrical signal to the first demodulation unit 1501 and the second demodulation unit 1502 respectively. The demodulation signal includes the first demodulation signal and the second demodulation signal. The first demodulation unit 1501 demodulates the electrical signal to obtain the first demodulation signal, and sends the first demodulation signal to the microwave control unit 152. Optionally, the first demodulation unit 1501 includes a first phase-locked amplifier and a first filter. The first demodulation unit 1501 receives the electrical signal sent by the photoelectric detection module 13 and the reference signal sent by the microwave modulation unit 142. The electrical signal and the reference signal are multiplied in the first phase-locked amplifier, and filtered by the first filter to obtain the first demodulation signal. The second demodulation unit 1502 demodulates the electrical signal to obtain a second demodulation signal, and sends the second demodulation signal to the microwave control unit 152. Optionally, the second demodulation unit 1502 includes a second phase-locked amplifier and a second filter. The second demodulation unit 1502 receives the electrical signal sent by the photoelectric detection module 13 and the reference signal sent by the microwave modulation unit 142. The electrical signal and the reference signal are multiplied in the second phase-locked amplifier and filtered by the second filter to obtain the second demodulation signal.

[0106] It should be noted that, in the microwave processing module 15 of this embodiment, the number of demodulation units can be set according to actual needs. For example, when the first microwave signal and the second microwave signal meet specific conditions, one demodulation unit can be set to demodulate the electrical signal to obtain the first demodulation signal and the second demodulation signal, or two demodulation units can be set to demodulate the electrical signal respectively to obtain the first demodulation signal and the second demodulation signal.

[0107] The microwave control unit 152 regulates the first microwave generating unit 1411 according to the received first demodulation signal so that the frequency of the first microwave signal matches the first resonance frequency, and regulates the second microwave generating unit 1412 according to the second demodulation signal so that the frequency of the second microwave signal matches the second resonance frequency. Specifically, in a manner substantially similar to the first embodiment, the first microwave generating unit 1411 and the second microwave generating unit 1412 are regulated according to the first demodulation signal and the second demodulation signal respectively by using a preset demodulation slope, so that the frequency of the first microwave signal can automatically track the first resonance frequency, and the frequency of the second microwave signal can automatically track the second resonance frequency.

[0108] In this embodiment, two microwave generating units are provided to respectively emit a first microwave signal and a second microwave signal, so that the frequency of the first microwave signal automatically tracks the first resonant frequency, and the frequency of the second microwave signal automatically tracks the second resonant frequency. According to the frequency of the first microwave signal and the frequency of the second microwave signal, by using formula (1) in the first embodiment, the magnetic induction intensity of the external magnetic field sensed by the passive probe 11 can be calculated by calculating the difference between the frequencies of the two microwave signals. The magnetic induction intensity calculated by this method can effectively suppress the influence of external factors such as temperature drift on the measurement results, thereby further improving the accuracy of the measurement results.

[0109] Embodiment 3

[0110] The present embodiment is a quantum current sensor, which is basically the same as the first embodiment or the second embodiment, wherein the similarities are not repeated here. The difference is that the quantum current sensor of the present embodiment includes a plurality of passive probes 11, and the plurality of passive probes 11 are distributed in an array to form an array of passive probes 11. Optionally, the number of passive probes 11 can be, for example, 2, 3, 4, or other suitable numbers.

[0111] In an alternative embodiment, reference Figure 8The number of passive probes 11 can be set to 3, for example, and the three passive probes 11 are linearly spaced and distributed in the same plane. Specifically, the three passive probes 11 are respectively recorded as a first probe 101, a second probe 102, and a third probe 103. The first probe 101, the second probe 102, and the third probe 103 are arranged in sequence, wherein the distance between the first probe 101 and the second probe 102 is l 12 , the distance between the first probe 101 and the third probe 103 is l 13 The magnetic induction intensities measured by the first probe 101, the second probe 102 and the third probe 103 are B 1 , B 2 and B 3 , then according to the principle of electromagnetic induction, the current I in the conductor 10 to be tested can be calculated as:

[0112]

[0113] in,

[0114] d=B 2 B 3 , a=B 3 / B 1 -B 3 / B 2 .

[0115] From the above formula (3), it can be seen that the current of the measured conductor 10 is independent of the distance from the three passive probes 11 to the measured conductor 10, and is also independent of the rotation angle of the measured conductor 10. The rotation angle of the measured conductor 10 is the angle between the straight lines formed by the measured conductor 10 and the three passive probes 11. Therefore, when installing and using the quantum current sensor, there is no need to consider the relative position between the passive probe 11 and the measured conductor 10, which reduces the installation difficulty of the quantum current sensor, improves the applicability of the equipment and the fault tolerance rate, and is conducive to the promotion and use of the quantum current sensor.

[0116] Embodiment 4

[0117] The present embodiment is a quantum current sensor, which is basically the same as the first embodiment or the second embodiment, wherein the similarities are not repeated here, and the difference is that the quantum current sensor of the present embodiment includes a plurality of passive probes 11, and the plurality of passive probes 11 are uniformly surrounded on the periphery of the conductor 10 to be measured, and optionally, the number of the passive probes 11 can be, for example, 3, 4, 5, 6, or other suitable numbers.

[0118] In an alternative embodiment, reference Fig. 9, the number of passive probes 11 can be set to 8, for example, and the 8 passive probes 11 are evenly arranged around the periphery of the conductor 10 to be measured, so that the angle between the connecting lines of adjacent passive probes 11 and the conductor 10 to be measured is 45°, and the distances between the 8 passive probes 11 and the conductor 10 to be measured are all R. According to the Ampere loop theorem, the current I of the conductor 10 to be measured can be calculated using the magnetic induction intensity measured by the 8 passive probes 11. Specifically, the current I of the conductor 10 to be measured can be given by the following formula:

[0119] ∮Bdl=Nu 0 I (4)

[0120] Among them, l is the length of the magnetic field closed loop, and N is the number of wires in the closed loop. In actual measurement, the value of N can be 1.

[0121] In this embodiment, multiple passive probes 11 are used to surround the outer circumference of the conductor 10 to be tested to measure the current of the conductor 10 to be tested, which can reduce the installation requirements of the equipment, improve the fault tolerance of the equipment, and thus improve the accuracy of the measurement results and the working reliability of the equipment, which is beneficial to the promotion and use of the product.

[0122] Embodiment 5

[0123] This embodiment provides a current measurement method, using any one of the quantum current sensors in the first to fourth embodiments to measure the current value of the conductor 10 to be measured, referring to Fig.10 , the current measurement method of this embodiment includes steps S1 to S8.

[0124] Step S1: placing a passive probe of a quantum current sensor at a preset position.

[0125] Specifically, the passive probe 11 is installed at a position in the power grid suitable for measuring the current of the conductor 10 to be measured. For example, the passive probe 11 can be set at a position close to the conductor 10 to be measured. The installation position of the passive probe 11 can be based on actual installation requirements and the power grid space.

[0126] In an optional embodiment, after the passive probe 11 of the quantum current sensor is arranged at a preset position, the following steps are further included: installing a voltage grading ring to the area of ​​the conductor 10 to be measured close to the passive probe 11. The use of the voltage grading ring can improve the uniformity of the electric field around the conductor 10 to be measured, prevent tip discharge, and ensure the working stability of the equipment and the accuracy of the measurement results.

[0127] Step S2: modulating the microwave signal based on a preset reference signal to generate a microwave modulated signal.

[0128] In this embodiment, the microwave generating unit 141 in the microwave modulation module 14 of the quantum current sensor is used to generate a microwave signal, and the generated microwave signal is modulated by the microwave modulation unit 142 to generate a microwave modulation signal. Optionally, the frequency of the microwave signal is set to the resonance frequency of the spin center of the passive probe 11.

[0129] Step S3: transmitting the laser signal of a preset wavelength and the microwave modulation signal to the passive probe to generate a fluorescence signal.

[0130] Specifically, the laser source 12 generates a laser signal of a preset wavelength, and transmits the laser signal to the passive probe 11 by using the optical transmission module 16; the microwave modulation module 14 is provided with a microwave transmitter 143, and the microwave modulation signal is sent to the passive probe 11 by using the microwave transmitter 143. The passive probe 11 generates a fluorescence signal under the action of the laser signal and the microwave modulation signal, and the intensity of the fluorescence signal can reflect the intensity of the external magnetic field sensed by the passive probe 11, thereby realizing the measurement of the magnetic field intensity.

[0131] Step S4: Convert the fluorescent signal into an electrical signal.

[0132] In this embodiment, the fluorescence signal is sent to the photoelectric detection module 13 of the quantum current sensor, and the photoelectric detection module 13 performs photoelectric conversion on the fluorescence signal to obtain an electrical signal.

[0133] Specifically, the fluorescence signal is transmitted to the photoelectric detection module 13 through the optical transmission module 16, and the spectrometer 121 of the quantum current sensor separates the reference light signal from the laser signal, differentially amplifies the reference light signal and the fluorescence signal to eliminate the laser signal in the fluorescence signal, and then performs photoelectric conversion on the differentially amplified fluorescence signal to obtain an electrical signal.

[0134] Step S5: Demodulate the electrical signal using the reference signal to obtain a demodulated signal.

[0135] In this embodiment, the demodulation unit 151 in the microwave processing module 15 is used to demodulate the electrical signal to obtain a demodulated signal. Specifically, the demodulation unit 151 is used to multiply and filter the electrical signal and the reference signal in sequence to obtain a demodulated signal. Optionally, the demodulated signal is a demodulated voltage, and the demodulation unit 151 is a DC signal with a frequency of zero.

[0136] Step S6: Calculate the frequency offset according to the demodulated signal and the pre-measured demodulation slope.

[0137] Specifically, within a certain range, there is a linear relationship between the frequency of the demodulated signal and the microwave signal. The slope of the linear relationship is recorded as the demodulation slope k. When the magnetic field sensed by the passive probe 11 changes, the frequency offset of the microwave frequency Δf=ΔV / k can be calculated based on the demodulation slope k and the change in the demodulated signal ΔV.

[0138] Step S7: regulating the microwave signal according to the frequency offset so that the frequency of the microwave signal matches the resonance frequency of the spin color center of the diamond structure.

[0139] Specifically, the microwave control unit 152 of the microwave processing module 15 is used to regulate the microwave generating unit 141 according to the frequency offset, so that the frequency of the microwave signal generated by the microwave generating unit 141 is correspondingly offset by Δf, so that the frequency of the microwave signal matches the resonance frequency of the spin color center of the diamond structure 112.

[0140] Step S8: Calculate the current value of the conductor to be tested according to the frequency of the microwave signal.

[0141] When the frequency of the microwave signal is the same as the resonance frequency of the spin center of the diamond structure 112, the intensity of the fluorescence signal shows a decreasing peak, and the intensity of the demodulated signal is zero. At this time, according to formula (1) of the first embodiment, the magnetic field intensity sensed by the passive probe 11 can be calculated, and then the current value of the conductor 10 to be tested can be calculated according to formula (2).

[0142] The current measurement method of this embodiment uses any one of the quantum current sensors in Embodiments 1 to 4 to measure the current value of the conductor 10 to be measured, and therefore has the same beneficial effects as Embodiments 1 to 4.

[0143] In summary, the present application provides a quantum current sensor and a current measurement method, comprising a passive probe, a laser source, a photoelectric detection module, a microwave modulation module and a microwave processing module; the passive probe comprises a diamond structure having a spin color center and is spaced apart from a conductor to be measured; the laser source generates a laser signal and transmits it to the passive probe to excite the spin color center of the diamond structure to generate a fluorescence signal; the microwave modulation module generates a microwave signal and modulates it to generate a microwave modulation signal; the photoelectric detection module converts the fluorescence signal into an electrical signal; the microwave processing module demodulates the electrical signal to generate a demodulation signal, and regulates the microwave modulation module according to the demodulation signal to match the frequency of the microwave signal with the resonance frequency of the spin color center of the diamond structure. The present application realizes contactless measurement of current through a passive probe, and remote transmission can be performed between the passive probe and the laser source and microwave modulation module, realizing remote monitoring of the operation status of the power grid, reducing the difficulty of use and installation, and improving the filtering effect of noise by modulating the microwave signal and demodulating the fluorescent signal, thereby improving the accuracy of measurement, and regulating the frequency of the microwave signal according to the demodulated signal so that it automatically tracks the resonance frequency of the spin color center, effectively improving the dynamic measurement range and measurement accuracy of the current. Therefore, the present application effectively overcomes various shortcomings in the prior art and has high industrial value.

[0144] The above embodiments are merely illustrative of the principles and effects of the present application and are not intended to limit the present application. Anyone familiar with the technology may modify, change or combine the above embodiments without violating the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by a person of ordinary skill in the art without departing from the spirit and technical ideas disclosed in the present application shall still be covered by the claims of the present application.

Claims

1. A quantum current sensor, characterized in that: It includes a passive probe, a laser source, a photoelectric detection module, a microwave modulation module and a microwave processing module; The laser source generates a laser signal of a preset wavelength and transmits it to the passive probe; The microwave modulation module is used to generate a microwave signal, modulate the microwave signal to generate a microwave modulation signal, and send the microwave modulation signal to the passive probe; The passive probe comprises a diamond structure having a spin color center and is spaced apart from the conductor to be tested. According to the laser signal and the microwave modulation signal, the diamond structure generates a fluorescence signal and transmits it to the photoelectric detection module; The photoelectric detection module converts the fluorescent signal into an electrical signal and sends it to the microwave processing module; The microwave processing module demodulates the electrical signal to generate a demodulation signal, and regulates the microwave modulation module according to the demodulation signal so that the frequency of the microwave signal matches the resonance frequency of the spin color center of the diamond structure.

2. The quantum current sensor according to claim 1, characterized in that: The passive probe also includes a circuit board, a microwave interface, an optical interface and a microwave receiver; The microwave receiver is connected to the microwave interface and is used to receive the microwave modulation signal, and the microwave modulation signal is transmitted to the circuit board via the microwave interface; The diamond structure is located between the circuit board and the optical interface. The circuit board is provided with a microwave input unit on a side close to the diamond structure. The microwave input unit partially or completely covers the diamond structure. The microwave modulation signal forms a uniform microwave field on the surface of the diamond structure through the microwave input unit. The optical interface is used to couple the laser signal to the surface of the diamond structure to excite the spin color center of the diamond structure, and the fluorescence signal is output to the passive probe via the optical interface.

3. The quantum current sensor according to claim 1 or 2, characterized in that: The quantum current sensor further comprises an optical transmission module, wherein the optical transmission module comprises a first optical transmission channel, a second optical transmission channel and an optical fiber circulator; The fiber optic circulator has a first interface, a second interface and a third interface. The first interface is used to receive the laser signal emitted by the laser source. The second interface is connected to the passive probe via the first optical transmission channel to transmit the laser signal to the passive probe and receive the fluorescence signal from the passive probe. The third interface is connected to the photoelectric detection module via the second optical transmission channel.

4. The quantum current sensor according to claim 3, characterized in that: The quantum current sensor also includes a spectrometer, which is located between the laser source and the optical fiber circulator to separate a reference light signal from the laser signal. The optical transmission module also includes a third optical transmission channel, and the reference light signal is transmitted to the photoelectric detection module via the third optical transmission channel.

5. The quantum current sensor according to claim 3, characterized in that: The quantum current sensor further includes an optical filter, which is arranged on the second light transmission channel.

6. The quantum current sensor according to claim 1, characterized in that: The microwave modulation module includes a microwave generating unit, a microwave modulation unit and a microwave transmitter; The microwave generating unit generates the microwave signal and sends it to the microwave modulating unit, wherein the frequency of the microwave signal is set to the resonance frequency of the spin color center of the diamond structure; The microwave modulation unit modulates the frequency of the microwave signal according to a preset reference signal to generate the microwave modulation signal, sends the reference signal to the microwave processing module, and sends the microwave modulation signal to the microwave transmitter; The microwave transmitter is used to transmit the microwave modulation signal.

7. The quantum current sensor according to claim 6, characterized in that: The microwave processing module includes a demodulation unit and a microwave control unit; The demodulation unit is used to demodulate the electrical signal according to the reference signal to obtain a demodulated signal, and send the demodulated signal to the microwave control unit; Based on the demodulation signal and a preset demodulation slope, the microwave control unit calculates a frequency offset, and regulates the microwave generating unit according to the frequency offset, so that the microwave generating unit generates a microwave signal that matches the resonance frequency of the spin color center of the diamond structure.

8. The quantum current sensor according to claim 7, characterized in that: The demodulation unit includes a lock-in amplifier and a filter.

9. The quantum current sensor according to claim 1, characterized in that: The microwave modulation module includes a first microwave generating unit, a second microwave generating unit, a microwave modulation unit and a microwave transmitter, and the microwave processing module includes a first demodulation unit, a second demodulation unit and a microwave control unit; The first microwave generating unit generates a first microwave signal, the microwave modulating unit modulates the first microwave signal to generate a first modulated signal, the second microwave generating unit generates a second microwave signal, the microwave modulating unit modulates the second microwave signal to form a second modulated signal, and the first modulated signal and the second modulated signal are transmitted to the passive connector via the microwave transmitter; The first demodulation unit and the second demodulation unit are both connected to the photoelectric detection module to receive the electrical signal, the first demodulation unit demodulates the electrical signal to obtain a first demodulation signal, and sends the first demodulation signal to the microwave control unit, the second demodulation unit demodulates the electrical signal to obtain a second demodulation signal, and sends the second demodulation signal to the microwave control unit; The resonant frequency of the diamond structure spin center includes a first resonant frequency and a second resonant frequency. The microwave control unit regulates the first microwave generating unit according to the first demodulation signal so that the frequency of the first microwave signal matches the first resonant frequency, and regulates the second microwave generating unit according to the second demodulation signal so that the frequency of the second microwave signal matches the second resonant frequency.

10. The quantum current sensor according to claim 1, characterized in that: There are multiple passive probes, and the multiple passive probes are distributed in an array to form a passive probe array.

11. The quantum current sensor according to claim 1, characterized in that: There are multiple passive probes, and the multiple passive probes are evenly surrounded by the outer circumference of the wire to be tested.

12. A current measurement method, using the quantum current sensor according to any one of claims 1 to 11 to measure the current value of a conductor to be measured, characterized in that: The following steps are involved: Arranging the passive probe of the quantum current sensor at a preset position; modulating the microwave signal based on a preset reference signal to generate a microwave modulated signal; Transmitting a laser signal of a preset wavelength and the microwave modulation signal to a passive probe to generate a fluorescence signal; converting the fluorescent signal into an electrical signal; Demodulating the electrical signal using the reference signal to obtain a demodulated signal; Calculating a frequency offset according to the demodulated signal and a preset demodulation slope; Regulating the microwave signal according to the frequency offset so that the frequency of the microwave signal matches the resonance frequency of the spin color center of the diamond structure; The current value of the conductor to be measured is obtained by calculation according to the frequency of the microwave signal.

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