CN111426993B - Magneto-electric effect-based magnetic gradiometer - Google Patents
Magneto-electric effect-based magnetic gradiometer Download PDFInfo
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- CN111426993B CN111426993B CN201911157642.1A CN201911157642A CN111426993B CN 111426993 B CN111426993 B CN 111426993B CN 201911157642 A CN201911157642 A CN 201911157642A CN 111426993 B CN111426993 B CN 111426993B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/02—Measuring direction or magnitude of magnetic fields or magnetic flux
- G01R33/06—Measuring direction or magnitude of magnetic fields or magnetic flux using galvano-magnetic devices
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/02—Measuring direction or magnitude of magnetic fields or magnetic flux
- G01R33/022—Measuring gradient
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A90/00—Technologies having an indirect contribution to adaptation to climate change
- Y02A90/30—Assessment of water resources
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- Measuring Magnetic Variables (AREA)
Abstract
The invention discloses a magnetic gradiometer based on magneto-electric effect, which comprises a reading unit and a plurality of multiferroic magnetic sensors connected in series, wherein the input end of the reading unit is connected with the multiferroic magnetic sensors, the output end of the reading unit is used as a signal reading end, and the relative placement directions among the multiferroic magnetic sensors are consistent. The invention utilizes the principle that the multiferroic magnetic sensor can generate potential difference after receiving magnetic field, and can realize superposition or cancellation of potential difference in a series connection mode, for example, the multiferroic magnetic sensor is placed in different magnetic field environments in a series connection mode, so that the intensity difference of different magnetic fields can be measured. The essential effects of the invention include: the direct measurement of the magnetic field intensity difference value is realized through a specific structure and a connection mode, no extra calculation is relied on, and the measurement is simple and quick.
Description
Technical Field
The invention relates to the field of magnetic field measurement, in particular to a magnetic gradiometer based on magneto-electric effect.
Background
The magneto-electric coupling effect refers to the phenomenon that materials generate electric polarization under the action of an external magnetic field or magnetization under the action of an external electric field. Thus, in a material system having both piezoelectric and magnetostrictive effects, a change in the external magnetic field may produce an electrical signal response through the magneto-electric coupling effect, and the electrical signal response has a linear relationship with the magnitude of the external magnetic field over a range. At present, the magnetoelectric material can detect 1.2x1 under the resonance frequency after good shielding treatment0 -10 An alternating magnetic field of T; by utilizing the high magnetic permeability and the strong magnetic anisotropy of the amorphous layer, the amorphous alloy/PZT fiber array laminated composite material has 10 degrees of direct current magnetic field -9 T sensitivity of up to 10 -5 Angular sensitivity of the degree. The existing research cases show the application prospect of the magnetic field sensor based on the magneto-electric material in the aspects of aviation, medical detection, geological exploration, information processing and the like, and the magnetic field sensor has the advantages of high sensitivity, low cost, low power consumption and the like.
The invention as set forth in grant publication number CN101047225B provides a magneto-electric coupling device comprising: two sheets of magnetostrictive material; a piezoelectric device positioned between and coupled to the two sheets of magnetostrictive material for converting displacement produced by the magnetostrictive material into an electrical signal; and a clamp on which the piezoelectric device and the two magnetostrictive material pieces are mounted and coupled together.
However, in many cases, the target magnetic field to be detected is often superimposed on the interfering magnetic field, and the numerical values read in the prior art are all superimposed magnetic fields, so that the target magnetic field cannot be directly read, and difficulty is brought to measurement.
Disclosure of Invention
Aiming at the problem that the prior art cannot directly acquire the magnetic field intensity of a target magnetic field from an interference magnetic field, the invention provides a magnetic gradiometer based on a magneto-electric effect, and a plurality of multiferroic magnetic sensors are connected in series by utilizing the induction principle of the multiferroic magnetic sensors, so that the difference value or the superposition value of the magnetic field intensity is directly acquired, and the problems are solved.
The following is a technical scheme of the invention.
The utility model provides a magnetic gradiometer based on magneto-electric effect, includes reading unit and a plurality of multiferroics magnetic sensor of establishing ties, the multiferroics magnetic sensor is connected to reading unit input, and reading unit's output is as signal reading end, and wherein the relative direction of putting between every multiferroics magnetic sensor is unanimous. The multiferroic magnetic sensor senses the magnetic field and then generates potential difference, and the superposition or cancellation of potential difference can be realized by utilizing a series connection mode, for example, the multiferroic magnetic sensor is placed in different magnetic field environments in a cancellation mode, so that the intensity difference of different magnetic fields can be measured, for example, when the magnetic field to be measured is superposed with other interference magnetic fields, the individual magnetic field intensity of the magnetic field to be measured can be accurately measured at one time by respectively placing the multiferroic magnetic sensor in the interference magnetic field and the superposition magnetic field. Wherein two multiferroic magnetic sensors are connected in series to form a first-order shaving meter, three multiferroic magnetic sensors are connected in series to form a second-order shaving meter, and the like.
Preferably, the multiferroic magnetic sensor comprises at least one piezoelectric layer and at least one magnetostrictive layer, wherein one end with the lowest working electromotive force is used as a cathode, one end with the highest working electromotive force is used as an anode, and the multiferroic magnetic sensors are connected in series in a homopolar connection mode. Through homopolar connection, the electromotive force of the adjacent multiferroic magnetic sensors can be counteracted, and the electromotive force corresponding to the magnetic field intensity difference is obtained when the whole numerical value is read.
Preferably, the multiferroic magnetic sensors are connected by a conductor, or adjacent multiferroic magnetic sensors are connected by sharing one piezoelectric layer. On the premise of connecting the homopolar connection modes in series, different physical connection modes are used, so that the manufacturing cost can be reduced, the manufacturing difficulty is reduced, and the reliability is improved.
Preferably, the reading unit comprises a signal processing module and a feedback module, wherein the input end of the signal processing module is connected with the multiferroic magnetic sensor, the output end of the signal processing module is connected with the input end of the feedback module, the feedback module generates a feedback magnetic field, and the output end of the signal processing module is used as the signal reading end. The feedback magnetic field generated by the feedback module compensates the magnetic field of the selected multiferroic magnetic sensor, so that the magnetic sensor works in a stable linear working interval, and the measurement accuracy is improved.
Preferably, the signal processing module comprises at least one amplifier, wherein the input end of the amplifier is connected with the multiferroic magnetic sensor, and the output end of the amplifier is used as the output end of the signal processing module.
Preferably, the signal processing module further comprises a low-pass filter, wherein an input end of the low-pass filter is connected with an output end of the amplifier, and an output end of the low-pass filter is used as an output end of the signal processing module.
Preferably, the feedback module comprises a feedback circuit and a magnetic field generating unit, wherein the input end of the feedback circuit is connected with the output end of the signal processing module, the output end of the feedback circuit is connected with the magnetic field generating unit, and the magnetic field generating unit generates a feedback magnetic field. On the basis of the existing feedback circuit, a magnetic field generating unit is connected to convert the fed-back electric signal into magnetic field intensity and is used for being superposed in a specific measured magnetic field, so that the superposed magnetic field is kept stable in the required magnetic field intensity, wherein the magnetic field generating unit can be any device capable of generating a controllable magnetic field according to the electric signal.
Preferably, the magnetic field generating unit is a coil group, and the coil group is disposed within a detection distance of the specific multiferroic magnetic sensor. The coil can generate a magnetic field, and has lower cost and simple structure. The magnetic field generating unit may influence any one of the multiferroic magnetic sensors.
Preferably, the multiferroic magnetic sensor is connected with the signal processing module through a transformer.
Preferably, the device further comprises a plurality of shielding boxes, and the shielding boxes are detachably connected with the multiferroic magnetic sensor. The shielding box can temporarily isolate the individual multiferroic magnetic sensors, so that the individual multiferroic magnetic sensors can no longer have potential differences, and the potential differences can be used for adjusting the finally output magnetic field intensity difference.
The essential effects of the invention include: the direct measurement of the magnetic field intensity difference value is realized through a specific structure and a connection mode, no extra calculation is needed, the measurement is simple and quick, the measured magnetic field is compensated through a feedback mode, the linear working point of the multiferroic magnetic sensor is locked, the linear interval limitation of the multiferroic magnetic sensor is avoided, and the final output voltage signal and the detected magnetic signal are ensured to have an ultra-wide linear working interval.
Drawings
FIG. 1 is a schematic diagram of a first embodiment of the present invention;
FIG. 2 is a schematic diagram of a second embodiment of the present invention;
FIG. 3 is a schematic diagram of a third embodiment of the present invention;
FIG. 4 is a schematic diagram of a fourth embodiment of the present invention;
in the figure: 1-first multiferroic magnetic sensor, 2-second multiferroic magnetic sensor, 3-signal processing module, 4-feedback circuit, 5-magnetic field generating unit, 6-third multiferroic magnetic sensor.
Detailed Description
The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application. In addition, numerous specific details are set forth in the following description in order to provide a better understanding of the present invention. It will be understood by those skilled in the art that the present invention may be practiced without some of these specific details. In some instances, well known methods, procedures, components, and circuits have not been described in detail so as not to obscure the present invention.
The terms "first" and "second" are used below for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present embodiment, unless otherwise specified, the meaning of "plurality" is two or more.
Embodiment one:
as shown in fig. 1, the magnetic gradiometer based on magneto-electric effect comprises a reading unit and two multiferroic magnetic sensors connected in series, which are respectively called a first multiferroic magnetic sensor 1 and a second multiferroic magnetic sensor 2, wherein the input end of the reading unit is connected with the first multiferroic magnetic sensor 1, the output end of the reading unit is used as a signal reading end, and the relative arrangement directions of the multiferroic magnetic sensors are consistent.
The multiferroic magnetic sensor of the embodiment comprises two piezoelectric layers and one magnetostrictive layer, wherein one end with the lowest working electromotive force is used as a cathode, the other end with the highest working electromotive force is used as an anode, and the multiferroic magnetic sensors are connected in series through leads in a homopolar connection mode. When the voltage is read from the outside, namely the electromotive force corresponding to the magnetic field intensity difference.
The embodiment has wide application, for example, when the magnetic field to be measured is in other magnetic fields, the individual magnetic field strength of the magnetic field to be measured can be accurately measured at one time by a mode of respectively placing multiferroic magnetic sensors.
The reading unit of this embodiment includes a signal processing module 3 and a feedback module, wherein an input end of the signal processing module 3 is connected with the multiferroic magnetic sensor, an output end of the signal processing module 3 is connected with an input end of the feedback module, and the feedback module generates a feedback magnetic field, wherein an output end of the signal processing module 3 is used as a signal reading end. The feedback magnetic field generated by the feedback module compensates the magnetic field of the selected multiferroic magnetic sensor, so that the magnetic sensor works in a stable linear working interval, and the measurement accuracy is improved.
The signal processing module 3 comprises an amplifier and a low-pass filter, wherein the input end of the amplifier is connected with the multiferroic magnetic sensor, the input end of the low-pass filter is connected with the output end of the amplifier, and the output end of the low-pass filter is used as the output end of the signal processing module 3.
The feedback module comprises a feedback circuit 4 and a magnetic field generating unit 5, wherein the input end of the feedback circuit 4 is connected with the output end of the signal processing module 3, the output end of the feedback circuit 4 is connected with the magnetic field generating unit 5, and the magnetic field generating unit 5 generates a feedback magnetic field. On the basis of the existing feedback circuit 4, a magnetic field generating unit 5 is connected to convert the fed-back electric signal into magnetic field intensity for being superposed in a specific measured magnetic field, so that the superposed magnetic field is kept stable in the required magnetic field intensity, wherein the magnetic field generating unit 5 can be any device capable of generating a controllable magnetic field according to the electric signal.
The magnetic field generating unit 5 is a coil group placed within a detection distance of the second multiferroic magnetic sensor 2. The coil can generate a magnetic field, and has lower cost and simple structure. The magnetic field generating unit 5 may affect any multiferroic magnetic sensor.
The embodiment is also provided with a shielding box which is detachably connected with the multiferroic magnetic sensor. One of the multiferroic magnetic sensors can be temporarily loaded into the shielding box when needed, and the two multiferroic magnetic sensors still remain electrically connected, so that the magnetic field strength is measured independently to meet different measurement requirements.
Embodiment two:
as shown in fig. 2, the difference between this embodiment and the previous embodiment is that the two multiferroic magnetic sensors are connected in series by sharing one piezoelectric layer.
Embodiment III:
as shown in fig. 3, the present embodiment differs from the first embodiment in that 3 multiferroic magnetic sensors are used, and a third multiferroic magnetic sensor 6 is connected in series with the first multiferroic magnetic sensor 1 and the second multiferroic magnetic sensor 2 to form a second-order magnetic shaving meter.
Embodiment four:
as shown in fig. 4, the difference between the present embodiment and the third embodiment is that the piezoelectric layer is shared by the piezoelectric layers.
From the foregoing description of the embodiments, it will be appreciated by those skilled in the art that, for convenience and brevity of description, only the above-described division of functional modules is illustrated, and in practical application, the above-described functional allocation may be implemented by different functional modules according to needs, i.e. the internal structure of a specific apparatus is divided into different functional modules to implement all or part of the functions described above.
In the embodiments provided in this application, it should be understood that the disclosed structures and methods may be implemented in other ways. For example, the embodiments described above with respect to structures are merely illustrative, e.g., the division of modules or units is merely a logical functional division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another structure, or some features may be omitted, or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via interfaces, structures or units, which may be in electrical, mechanical or other forms.
The units described as separate parts may or may not be physically separate, and the parts shown as units may be one physical unit or a plurality of physical units, may be located in one place, or may be distributed in a plurality of different places. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.
In addition, each functional unit in the embodiments of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit. The integrated units may be implemented in hardware or in software functional units.
The integrated units, if implemented in the form of software functional units and sold or used as stand-alone products, may be stored in a readable storage medium. Based on such understanding, the technical solution of the embodiments of the present application may be essentially or a part contributing to the prior art or all or part of the technical solution may be embodied in the form of a software product stored in a storage medium, including several instructions to cause a device (may be a single-chip microcomputer, a chip or the like) or a processor (processor) to perform all or part of the steps of the methods of the embodiments of the present application. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read Only Memory (ROM), a random access memory (random access memory, RAM), a magnetic disk, or an optical disk, or other various media capable of storing program codes.
The foregoing is merely specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily think about changes or substitutions within the technical scope of the present application, and the changes and substitutions are intended to be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.
Claims (5)
1. The magnetic gradiometer based on magneto-electric effect is characterized by comprising a reading unit and a plurality of multiferroic magnetic sensors connected in series, wherein the input end of the reading unit is connected with the multiferroic magnetic sensors, the output end of the reading unit is used as a signal reading end, and the relative placement directions among the multiferroic magnetic sensors are consistent; the multiferroic magnetic sensor comprises at least one piezoelectric layer and at least one magnetostrictive layer, wherein one end with the lowest working electromotive force is used as a cathode, one end with the highest working electromotive force is used as an anode, and the multiferroic magnetic sensors are connected in series in a homopolar connection mode;
the reading unit comprises a signal processing module and a feedback module, wherein the input end of the signal processing module is connected with the multiferroic magnetic sensor, the output end of the signal processing module is connected with the input end of the feedback module, the feedback module generates a feedback magnetic field, and the output end of the signal processing module is used as a signal reading end;
the signal processing module comprises at least one amplifier, the input end of the amplifier is connected with the multiferroic magnetic sensor, and the output end of the amplifier is used as the output end of the signal processing module;
the feedback module comprises a feedback circuit and a magnetic field generating unit, wherein the input end of the feedback circuit is connected with the output end of the signal processing module, the output end of the feedback circuit is connected with the magnetic field generating unit, and the magnetic field generating unit generates a feedback magnetic field;
the magnetic field generating unit is a coil group which is arranged in the detection distance of the specific multiferroic magnetic sensor.
2. A magnetic gradiometer based on the magneto-electric effect according to claim 1, wherein the multiferroic magnetic sensors are connected by conductors or adjacent multiferroic magnetic sensors are connected by sharing a piezoelectric layer.
3. The magnetic gradiometer of claim 2 wherein the signal processing module further comprises a low pass filter having an input coupled to the output of the amplifier, the output of the low pass filter being the output of the signal processing module.
4. A magnetic gradiometer based on magneto-electric effect according to claim 3, wherein the multiferroic magnetic sensor is connected to the signal processing module via a transformer.
5. A magnetic gradiometer based on the magneto-electric effect according to claim 1 or 2, further comprising a plurality of shield boxes detachably connected to the multiferroic magnetic sensor.
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| CN201911157642.1A CN111426993B (en) | 2019-11-22 | 2019-11-22 | Magneto-electric effect-based magnetic gradiometer |
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| CN203732707U (en) * | 2014-03-05 | 2014-07-23 | 华中科技大学 | System for testing magneto-electric properties of multiferroic materials under pulsed high magnetic field |
| CN110320481A (en) * | 2019-07-11 | 2019-10-11 | 南京理工大学 | It is a kind of based on magnetoelectricity-electrochromic effect magnetic field visualization sensor |
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| US6327122B1 (en) * | 1998-12-04 | 2001-12-04 | International Business Machines Corporation | Spin valve sensor having antiparallel (AP) pinned layer with high resistance and low coercivity |
| US8760157B2 (en) * | 2009-09-17 | 2014-06-24 | The Boeing Company | Multiferroic antenna/sensor |
| CN104198961B (en) * | 2014-07-18 | 2017-06-13 | 中国科学院上海微系统与信息技术研究所 | Using the superconducting quantum interference device Magnetic Sensor of single operational amplifier |
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| CN203732707U (en) * | 2014-03-05 | 2014-07-23 | 华中科技大学 | System for testing magneto-electric properties of multiferroic materials under pulsed high magnetic field |
| CN110320481A (en) * | 2019-07-11 | 2019-10-11 | 南京理工大学 | It is a kind of based on magnetoelectricity-electrochromic effect magnetic field visualization sensor |
Non-Patent Citations (1)
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| 《多铁性磁电复合薄膜的研究进展及应用》;连紫薇 等;《Science Discovery》;第1-8页 * |
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