Electromagnetic sensor and magnet frame

Abstract

The utility model relates to the technical field of sensors, in particular to an electromagnetic sensor and a magnet frame. An electromagnetic sensor includes: a base tube; the first monitoring optical fiber and the second monitoring optical fiber are respectively arranged in the base tube, the first monitoring optical fiber is used for monitoring magnetic field change in the base tube, and the second monitoring optical fiber is used for monitoring temperature change in the base tube. The utility model provides an electromagnetic sensor and a magnet frame, aiming at solving the problems that an electromagnetic sensor often needs to carry out measurement in a complex magnetic field, and a traditional magnetic field sensor mostly carries out measurement through an electric signal and is subjected to electromagnetic interference in a strong magnetic field environment, so that a test result is inaccurate.

Description

Technical Field

[0001] The utility model relates to the technical field of sensors, in particular to an electromagnetic sensor and a magnet frame. Background Art

[0002] Electromagnetic measurement is a necessary means for condition monitoring and performance evaluation in fields such as electric power, national defense, and nuclear fusion. Most traditional electromagnetic measurement sensors are based on the electrical measurement method. Their measurement results are affected by electromagnetic interference, and there are problems such as poor insulation, large volume, and complex wiring. Especially when measuring in a complex strong magnetic field environment, the above problems are more prominent, resulting in inaccurate test results. Summary of the Utility Model

[0003] Therefore, the technical problem to be solved by the utility model is to overcome the defect that existing electromagnetic sensors often need to measure in a complex magnetic field, and most traditional magnetic field sensors measure through electrical signals and are affected by electromagnetic interference in a strong magnetic field environment, resulting in inaccurate test results, so as to provide an electromagnetic sensor and a magnet frame.

[0004] To solve the above problems, the utility model provides an electromagnetic sensor, including:

[0005] A base tube;

[0006] A first monitoring optical fiber and a second monitoring optical fiber, the first monitoring optical fiber and the second monitoring optical fiber are respectively arranged in the base tube, the first monitoring optical fiber is used to monitor the magnetic field change in the base tube, and the second monitoring optical fiber is used to monitor whether the temperature in the base tube changes.

[0007] Optionally, it further includes a first optical fiber sleeve and a second optical fiber sleeve, the first optical fiber sleeve and the second optical fiber sleeve are arranged in parallel, the first optical fiber sleeve is sleeved on the outer periphery of the first monitoring optical fiber, and the second optical fiber sleeve is sleeved on the outer periphery of the second monitoring optical fiber.

[0008] Optionally, one end of the base tube is provided with a semi-circular end, and a groove is provided on the end face of the semi-circular end.

[0009] Optionally, the end of the first monitoring optical fiber extending into the base tube is provided with a first fiber Bragg grating, the first fiber Bragg grating is pasted on the surface of a high-temperature superconducting tape, and the high-temperature superconducting tape is placed in the groove.

[0010] Optionally, the end of the second monitoring optical fiber extending into the base tube is provided with a second fiber Bragg grating, and the outer periphery of the second fiber Bragg grating is sleeved with a heat conduction ring, and the heat conduction ring is arranged on the side surface of the high-temperature superconducting tape.

[0011] Optionally, it further includes a position indicator, which is arranged in parallel with the high-temperature superconducting tape and extends out of the end of the base tube.

[0012] Optionally, the base tube is provided with a through-flow guiding hole, and a refrigeration medium is suitable for flowing into the guiding hole.

[0013] Optionally, a plugging head is provided at the end of the guiding hole located in the base tube.

[0014] Optionally, it further includes a test chamber cover, which includes a receiving groove adapted to the semi-circular end and is configured to receive the semi-circular end therein.

[0015] A magnet frame includes the above electromagnetic sensor and a magnet frame body.

[0016] The technical solution of the present utility model has the following advantages:

[0017] 1. The electromagnetic sensor provided by the present utility model includes: a base tube; a first monitoring optical fiber and a second monitoring optical fiber, which are respectively arranged in the base tube. The first monitoring optical fiber is used to monitor the magnetic field change in the base tube, and the second monitoring optical fiber is used to monitor whether the temperature in the base tube changes. By monitoring the magnetic field change with the first monitoring optical fiber and the temperature change with the second monitoring optical fiber, and by monitoring the temperature in the base tube, once the temperature in the base tube exceeds the preset value, it can remind the on-site personnel to avoid affecting the measurement result due to temperature change, thereby ensuring the accuracy of the magnetic field intensity measurement result.

[0018] 2. The electromagnetic sensor provided by the present utility model further includes a first optical fiber sleeve and a second optical fiber sleeve, which are arranged in parallel. The first optical fiber sleeve is sleeved on the outer periphery of the first monitoring optical fiber, and the second optical fiber sleeve is sleeved on the outer periphery of the second monitoring optical fiber. The first optical fiber sleeve protects the first monitoring optical fiber, and the second optical fiber sleeve protects the second monitoring optical fiber.

[0019] 3. For the electromagnetic sensor provided by the present utility model, one end of the base tube is provided with a semi-circular end, and the end face of the semi-circular end is provided with a groove for placing the ends of the first monitoring optical fiber and the second monitoring optical fiber.

[0020] 4. For the electromagnetic sensor provided by the present utility model, the end of the first monitoring optical fiber extending into the base tube is provided with a first fiber Bragg grating, which is pasted on the surface of the high-temperature superconducting tape. The high-temperature superconducting tape is placed in the groove. When a magnetic field acts on the high-temperature superconducting tape, due to perfect diamagnetism, the high-temperature superconducting tape will generate strain, which is then transmitted to the first fiber Bragg grating, causing its wavelength to change. The magnetic field can be detected by detecting the wavelength change.

[0021] 5. For the electromagnetic sensor provided by the present utility model, a second fiber Bragg grating is provided at the end of the second monitoring optical fiber extending into the base tube. The outer periphery of the second fiber Bragg grating is sleeved with a heat conduction ring, and the heat conduction ring is placed on the side of the high-temperature superconducting tape. The temperature of the high-temperature superconducting tape is conducted through the heat conduction ring, and then the temperature change near the high-temperature superconducting tape area is sensed by the second fiber Bragg optical fiber. The second Bragg grating is freely placed in the heat conduction ring and is in non-rigid contact with it, so that the second Bragg grating is only sensitive to temperature and is used to monitor the temperature at the position of the second Bragg grating. Through the second Bragg grating, temperature and magnetic field decoupling of the first Bragg grating are performed.

[0022] 6. The electromagnetic sensor provided by the present utility model further includes a position indicating member, which is arranged in parallel with the high-temperature superconducting tape and extends out of the end of the base tube. When the base tube rotates, the arrangement of the position indicating member facilitates personnel to master the position and angle of the high-temperature superconducting tape.

[0023] 7. For the electromagnetic sensor provided by the present utility model, the base tube is provided with a through-flow guiding hole, and a refrigerating medium is suitable for flowing into the guiding hole, and the refrigerating medium keeps the base tube within a preset temperature.

[0024] 8. For the electromagnetic sensor provided by the present utility model, a plugging head is provided at the end of the guiding hole located in the base tube to prevent the outflow of the refrigerating medium.

[0025] 9. The electromagnetic sensor provided by the present utility model further includes a test cavity cover, which includes a receiving groove adapted to the semi-ring end to receive the semi-ring end therein, and the test cavity cover protects the semi-ring end.

[0026] 10. For the magnet frame provided by the present utility model, since it adopts the electromagnetic sensor described in any one of the above, it has the advantages described in any one of the above, and further includes a magnet frame body. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the specific embodiments of the present utility model or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present utility model. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0028] Figure 1 It is a schematic diagram of the electromagnetic sensor provided in the embodiments of the present utility model;

[0029] Figure 2 It is a schematic diagram of the electromagnetic sensor provided in the embodiments of the present utility model from another angle;

[0030] Figure 3 Schematic diagram of the test chamber cover provided in the embodiment of the present utility model;

[0031] Figure 4 Schematic diagram of the connection between the electromagnetic sensor and the test chamber cover provided in the embodiment of the present utility model;

[0032] Figure 5 Schematic diagram of the electromagnetic sensor and the test chamber cover placed in the electromagnetic housing provided in the embodiment of the present utility model.

[0033] Description of the reference numerals: 1, base tube; 2, second optical fiber sleeve; 3, first optical fiber sleeve; 4, position indicator; 5, snap ring; 6, semi-ring end; 7, diversion hole; 8, heat conducting ring; 9, high temperature superconducting tape; 10, groove; 11, plugging head; 12, test chamber cover; 13, receiving groove; 14, magnet housing. Detailed embodiments

[0034] Next, the technical solutions of the present utility model will be clearly and completely described in conjunction with the accompanying drawings. Obviously, the described embodiments are some, but not all, of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0035] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present utility model. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0036] In the description of the present utility model, it should be noted that unless otherwise clearly defined and limited, the terms "installed", "connected", "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0037] In addition, the technical features involved in different embodiments of the present utility model described below can be combined with each other as long as they do not conflict with each other.

[0038] As shown in Figure 1 -5, a specific embodiment of an electromagnetic sensor includes: a base tube 1, a first monitoring optical fiber and a second monitoring optical fiber disposed within the base tube 1, and a clamping ring 5 provided on the outer peripheral surface of the base tube 1. Specifically, the base tube 1 is made of an insulating resin rod.

[0039] As shown in Figure 1 、 Figure 2 , the base tube 1 is annular, one end of the base tube 1 is provided with a semi-circular end 6, and a groove 10 is provided on the end surface of the semi-circular end 6.

[0040] As shown in Figure 1 、 Figure 2 , it further includes a first optical fiber sleeve 3 and a second optical fiber sleeve 2. The first optical fiber sleeve 3 and the second optical fiber sleeve 2 are arranged in parallel. The first optical fiber sleeve 3 is sleeved on the outer periphery of the first monitoring optical fiber, the second optical fiber sleeve 2 is sleeved on the outer periphery of the second monitoring optical fiber, and the first optical fiber sleeve 3 and the second optical fiber sleeve 2 are respectively fixedly connected to the base tube 1. As shown in Figure 1 、 Figure 2 , the end of the first monitoring optical fiber extending into the base tube 1 is provided with a first fiber Bragg grating, the first fiber Bragg grating is adhered to the surface of the high-temperature superconducting tape 9, the high-temperature superconducting tape 9 is placed in the groove 10, and the high-temperature superconducting tape 9 and the first fiber Bragg grating are adhesively fixedly connected. As shown in Figure 1 、 Figure 2 , the end of the second monitoring optical fiber extending into the base tube 1 is provided with a second fiber Bragg grating, the outer periphery of the second fiber Bragg grating is sleeved with a heat conduction ring 8, the heat conduction ring 8 is disposed on the side surface of the high-temperature superconducting tape 9 and they are not in contact with each other, the heat conduction ring 8 is disposed close to the high-temperature superconducting tape 9, and the second fiber Bragg grating can move freely within the heat conduction ring 8 and is a non-rigid connection. Specifically, the heat conduction ring 8 is made of copper. For the second fiber Bragg grating, both the temperature and strain changes will cause the wavelength to change. During use, it is necessary to decouple the temperature and strain to distinguish whether it is the temperature or the strain that causes the wavelength change. During use, the heat conduction ring 8 has the following functions: one is to protect the second fiber Bragg grating and prevent it from being damaged by external forces; the second is that since the second fiber Bragg grating moves freely within the heat conduction ring 8, even if the external strain changes, the second Bragg grating cannot sense it, and the second Bragg grating is only sensitive to temperature; the third is that the heat conduction ring 8 is disposed on the side surface of the high-temperature superconducting tape 9, which is convenient for them to be in the same temperature region, that is, the temperature at the first fiber Bragg grating can be monitored to distinguish whether the factor causing the wavelength change of the first fiber Bragg grating is temperature or magnetic field.

[0041] As shown in Figure 1 , a diversion hole 7 is further provided in the base tube 1, a refrigerating medium is suitable for flowing into the diversion hole 7, and a plug 11 is provided at the end of the diversion hole 7 facing away from the semi-circular end 6. Specifically, the refrigerating medium is liquid nitrogen.

[0042] To protect the semi-ring end 6, as Figure 3 shown, it further includes a test chamber cover 12. The test chamber cover 12 includes a receiving groove 13, which is adapted to the semi-ring end 6 and can receive the semi-ring end 6 therein, and the test chamber cover 12 protects the semi-ring end 6.

[0043] A magnet frame, as Figure 4 and Figure 5 shown, includes the above-mentioned magnet sensor and a magnet frame body 14. The part of the magnet sensor with the semi-ring end 6 extends into the magnet frame body 14. The clamping ring 5 is clamped and fixed to the magnet frame body 14, and there is a coil in the magnet frame body 14. Different intensities of magnetic fields are generated by changing the current in the coil.

[0044] Before the electromagnetic sensor is used, the magnet frame body 14 needs to be used as a calibration magnet to calibrate the electromagnetic sensor first: The test chamber cover 12 cooperates with the semi-ring end 6 to make the refrigeration medium flow into the receiving groove 13 through the diversion hole 7. After being filled with the refrigeration medium, it is sealed with a plugging head 11. Then, the part of the magnet sensor with the semi-ring end 6 is extended into the magnet frame body 14, and the clamping ring 5 is clamped and fixed to the magnet frame body 14. By applying different magnitudes of current to the coil, the wavelength changes of the first fiber Bragg grating at different magnetic field intensities are recorded, and a change relationship between the magnetic field intensity and the wavelength can be obtained. Then, when the base tube 1 is rotated at the same magnetic field intensity, the change relationships between the magnetic fields and wavelengths at different angles are obtained with the help of the position indicating member 4, so as to calibrate the electromagnetic sensor. At the same time, the second fiber Bragg grating judges the temperature in the receiving groove 13, especially the temperature at the high-temperature superconducting tape, according to the heat transferred by the heat conduction ring 8 to monitor the temperature change, so as to realize the decoupling of the first Bragg grating for temperature and magnetic field.

[0045] Actually, the high-temperature superconducting tape 9 has perfect diamagnetism, that is, when an external magnetic field acts on the surface of the high-temperature superconducting tape 9 in the superconducting state, a superconducting current will appear on the surface of the superconductor due to the magnetic field of the magnet. The magnetic field formed by this superconducting current inside the superconductor is exactly equal in magnitude and opposite in direction to the magnetic field of the magnet. Therefore, a force will be formed between the magnet and the high-temperature superconducting tape 9, resulting in strain of the high-temperature superconducting tape 9. The fiber Bragg grating is a fiber device for wavelength demodulation. When the temperature or stress where the fiber Bragg grating is located changes, the change of the grating pitch period and the refractive index of the fiber core causes the center wavelength of the fiber Bragg grating to shift. By detecting the shift of the Bragg wavelength, the change of the temperature and stress to be measured can be obtained.

[0046] The electromagnetic sensor provided by the present utility model is based on the perfect diamagnetism of the high-temperature superconducting tape 9 and the principle of fiber Bragg grating. The high-temperature superconducting tape 9 is adhesively fixed to the first fiber Bragg grating. After the magnetic field is generated, due to the interaction between the magnetic field and the perfect diamagnetism, the high-temperature superconducting tape 9 will generate strain, resulting in a change in the wavelength of the first fiber Bragg grating. By detecting the change in wavelength, the magnetic field strength can be detected.

[0047] The electromagnetic sensor provided by the present utility model has the following advantages: (1) By utilizing the inherent perfect diamagnetism of the high-temperature superconducting tape 9 and the characteristic that the wavelength of the fiber Bragg grating changes when it is stressed, the measurement of the magnetic field is realized. It has the characteristics of anti-electromagnetic interference, high insulation resistance, small volume, and simple wiring, and is suitable for magnetic measurement in complex electromagnetic environments; (2) The sensor has a simple structure, is easy to manufacture, and is convenient to use; (3) By monitoring the temperature change through the second monitoring optical fiber, the temperature inside the base tube 1 is monitored. Once the temperature inside the base tube 1 exceeds the preset value, the on-site personnel will be reminded to avoid affecting the superconducting state of the high-temperature superconducting tape 9 due to temperature changes and ensure the accuracy of the magnetic field strength measurement result; (4) The electromagnetic sensor of the present application is based on the fiber Bragg grating. The fiber Bragg grating is sensitive to both temperature and magnetic field (strain), and the changes in temperature and magnetic field (strain) will both cause changes in the wavelength of the fiber Bragg grating. By monitoring the temperature through the second fiber Bragg grating, the decoupling of the first Bragg grating to temperature and magnetic field (strain) is realized to ensure the accuracy of the magnetic field measurement result.

[0048] As an alternative embodiment, the material of the heat-conducting ring 8 can also be other heat-conducting materials such as aluminum and iron.

[0049] Obviously, the above embodiments are merely examples given for clear illustration and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation manners here. And the obvious changes or modifications derived therefrom are still within the protection scope of the present utility model.

Claims

1. An electromagnetic sensor, characterized in that: include: Base tube (1); A first monitoring optical fiber and a second monitoring optical fiber, wherein the first monitoring optical fiber and the second monitoring optical fiber are respectively arranged in a base tube (1), the first monitoring optical fiber is used to monitor the change of the magnetic field in the base tube (1), and the second monitoring optical fiber is used to monitor whether the temperature in the base tube (1) changes.

2. The electromagnetic sensor according to claim 1, characterized in that: It also comprises a first optical fiber sleeve (3) and a second optical fiber sleeve (2), wherein the first optical fiber sleeve (3) and the second optical fiber sleeve (2) are arranged in parallel, the first optical fiber sleeve (3) is sleeved on the outer periphery of the first monitoring optical fiber, and the second optical fiber sleeve (2) is sleeved on the outer periphery of the second monitoring optical fiber.

3. The electromagnetic sensor according to claim 2, characterized in that: One end of the base pipe (1) is provided with a semi-ring end (6), and the end surface of the semi-ring end (6) is provided with a groove (10).

4. The electromagnetic sensor according to claim 3, characterized in that: A first fiber Bragg grating is provided at the end of the first monitoring optical fiber extending into the substrate tube (1); the first fiber Bragg grating is adhered to the surface of a high-temperature superconducting tape (9); and the high-temperature superconducting tape (9) is placed in the groove (10).

5. The electromagnetic sensor according to claim 4, characterized in that: A second fiber Bragg grating is provided at the end of the second monitoring optical fiber extending into the base tube (1), and the outer periphery of the second fiber Bragg grating is sleeved on a heat conducting ring (8), and the heat conducting ring (8) is arranged on the side of the high-temperature superconducting tape (9).

6. The electromagnetic sensor according to claim 5, characterized in that: It also comprises a position indicator (4), wherein the position indicator (4) is arranged in parallel with the high-temperature superconducting tape (9), and the position indicator (4) extends out of the end of the substrate tube (1).

7. The electromagnetic sensor according to claim 1, characterized in that: The base tube (1) is provided with a flow guide hole (7) which is arranged through the base tube, and the flow guide hole (7) is suitable for the refrigerant to flow into the base tube.

8. The electromagnetic sensor according to claim 7, characterized in that: The guide hole (7) is located at the end of the base pipe (1) and is provided with a plugging head (11).

9. The electromagnetic sensor according to claim 3, characterized in that: The invention also comprises a test chamber cover (12), wherein the test chamber cover (12) comprises a receiving groove (13), wherein the receiving groove (13) is adapted to the semi-ring end (6), and the receiving groove (13) is used to receive the semi-ring end (6) therein.

10. A magnet frame, characterized in that: The electromagnetic sensor comprises the electromagnetic sensor as claimed in any one of claims 1 to 9, and further comprises a magnetic frame (14).

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