Magnetoelectric coupling current sensor and preparation method thereof

Abstract

The invention discloses a magnetoelectric coupling current sensor and a preparation method thereof, and relates to the technical field of electromagnetic quantity measurement. The electric coupling current sensor comprises an opening magnetism gathering ring and a magnetoelectric coupling sensitive element. The magnetoelectric coupling sensitive element comprises a magnetostriction phase layer, a piezoelectric phase layer and a rigid base which are sequentially connected from top to bottom, the piezoelectric phase layer comprises four piezoelectric materials which have the same piezoelectric performance and are linearly arranged at equal intervals, the polarization directions of the piezoelectric materials are alternately arranged in the arrangement direction, a flexible electrode is arranged on the charge output face of each piezoelectric material, and the flexible electrode is arranged on the rigid base. The flexible electrodes are connected end to end according to an arrangement sequence to form a full-bridge differential circuit; and the magnetoelectric coupling sensitive element is arranged at the opening of the opening magnetism gathering ring to form the magnetoelectric coupling current sensor in an in-plane shear mode. The device has the advantages of high sensitivity, low cost, high stability, passivity and simple rear-end circuit.

Description

Technical Field

[0001] The present invention relates to the technical field of electromagnetic quantity measurement, and in particular to a magnetoelectric coupling current sensor and a preparation method thereof. Background Art

[0002] With the continuous development of modern science and technology, the demand for current measurement in various industries is increasing. In many fields such as industrial manufacturing, power grid monitoring, electric vehicles, etc., there is an urgent need for broadband current measurement. With the rapid development of smart grids, higher requirements are also put forward for current detection in power grids.

[0003] At present, the commonly used current sensors in the industry include current transformers, shunts, fiber optic current sensors, Hall current sensors, Rogowski coils, fluxgate current sensors, magnetoresistive current sensors, etc. Among them, the current transformer has a limited measurement frequency band; the shunt is a contact sensor, and there is a heating problem when measuring large currents; the fiber optic current sensor is easily affected by environmental factors such as vibration and temperature, resulting in reduced accuracy; the Hall current sensor cannot be used to measure MHz currents, and the accuracy is easily affected by temperature; the accuracy of the Rogowski coil is greatly reduced when measuring small currents; the fluxgate sensor is limited by materials, and its manufacturing cost is relatively high; and the magnetoresistive current sensor also has the problem of severe attenuation of the amplitude-frequency characteristic when measuring high-frequency MHz currents.

[0004] In summary, the existing current detection technology has many shortcomings in measurement sensitivity and measurement range. In view of the urgent demand for broadband and low-cost current sensors in application scenarios, it is necessary to design a broadband current sensor with wide measurement bandwidth, low cost and strong stability. Summary of the invention

[0005] The present invention provides a magnetoelectric coupling current sensor and a preparation method thereof, so as to solve the problems that the existing current sensor is insufficient in measurement frequency band and measurement sensitivity.

[0006] The present invention is achieved through the following technical solutions:

[0007] A first aspect of the present invention provides a magnetoelectric coupling current sensor, comprising:

[0008] Open magnetic ring;

[0009] A magnetoelectric coupling sensitive element comprises a magnetostrictive phase layer, a piezoelectric phase layer and a rigid base connected from top to bottom;

[0010] The piezoelectric phase layer includes four piezoelectric materials with the same piezoelectric properties and arranged linearly at equal intervals. The polarization directions of the piezoelectric materials are arranged alternately in the arrangement direction. A flexible electrode is arranged on the charge output surface of each piezoelectric material. The flexible electrodes are connected end to end in the arrangement order to form a full-bridge differential circuit.

[0011] The magneto-electric coupling sensitive element is arranged at the opening of the open magnetic focusing ring to form an in-plane shear mode magneto-electric coupling current sensor.

[0012] The present invention proposes a contactless magnetoelectric coupling current sensor, in which a conductor to be measured is placed at the center of an open magnetic focusing ring. The current to be measured passes through the conductor and the center of the magnetic focusing ring, generating a circular magnetic field around the conductor, which is gathered at the opening through the open magnetic focusing ring to form a uniform magnetic field. The magnetostrictive phase of the magnetoelectric coupling sensitive element arranged at the opening is magnetized along the magnetic field direction, and generates mechanical contraction of the same frequency as the high-frequency magnetic field signal at the opening of the magnetic focusing ring, thereby driving the piezoelectric phase connected to it to generate in-plane shear vibration, and outputting a voltage signal of the same frequency on the lead-out flexible electrode, completing the contactless sensing of current-magnetic field-mechanical vibration-voltage. Four piezoelectric materials are connected to form a full-bridge differential structure, which improves the sensitivity to current measurement, so that the sensor has a very high resonant output voltage in the MHz frequency band, and also has a high sensitivity in low-frequency current measurement, thereby improving the measurement signal-to-noise ratio of wide-band current signals.

[0013] Furthermore, the magnetostrictive phase layer and the piezoelectric phase layer, and the piezoelectric phase layer and the rigid base are tightly bonded by epoxy resin.

[0014] Furthermore, the two output voltage signals of the full-bridge differential circuit are connected to an adder, and the output end of the adder is connected to an amplifying and filtering circuit to obtain a stable standardized output.

[0015] Furthermore, the piezoelectric material is in a hexahedral shape, and the polarization direction is along the body diagonal.

[0016] Furthermore, the piezoelectric material is made of AlN, quartz, LiNbO3, BaTiO3, ZnO, Pb(Zr,Ti)O3, Pb(Mg,Nb)O3-PbTiO3, Pb(Zn,Nb)O3-PbTiO3, Pb(Ni,Nb)O3-Pb(Zr,Ti)O3 or BiScO3-PbTiO3.

[0017] Furthermore, the magnetostrictive phase layer includes at least two layers of magnetostrictive thin sheets, and the magnetostrictive thin sheets are bonded by epoxy resin.

[0018] Furthermore, the material of the magnetostrictive sheet is one of Metglas, nickel-manganese-gallium alloy, nickel-iron oxide, terbium-dysprosium-iron, and cobalt-iron oxide, or a composite material of one of Metglas, nickel-manganese-gallium alloy, nickel-iron oxide, terbium-dysprosium-iron, and cobalt-iron oxide and a polymer.

[0019] Furthermore, the material of the rigid base is brass, copper, phosphor bronze, aluminum alloy, titanium alloy, glass or ceramic;

[0020] Furthermore, the outer diameter of the open magnetic focusing ring (100) is 30 to 100 mm, the inner diameter is 25 to 95 mm, and the diameter is 5 to 30 mm.

[0021] A second aspect of the present invention provides a preparation method for preparing the magnetoelectric coupling current sensor according to any one of the first aspects of the present invention, comprising:

[0022] Preparation of magnetostrictive phase layer: processing magnetostrictive material into magnetostrictive thin sheets, bonding multiple layers of magnetostrictive material with epoxy resin and leaving them to stand at room temperature to obtain magnetostrictive phase layer;

[0023] Preparation of piezoelectric phase layer: cutting the piezoelectric material into blocks, ultrasonically cleaning with ultrapure water, selecting four piezoelectric materials with the same performance parameters, making silver electrodes on two opposite surfaces in the width direction of each piezoelectric material, and polarizing along the body diagonal direction; arranging the four piezoelectric materials linearly in an alternating and equidistant manner according to the polarization direction, connecting the silver electrodes end to end in the order of arrangement to form a full-bridge differential structure, and obtaining the piezoelectric phase layer;

[0024] Preparation of magnetoelectric coupling sensitive element: the upper surface of the piezoelectric phase layer is tightly bonded to the magnetostrictive phase layer through epoxy resin, and the lower surface is tightly bonded to the rigid base through epoxy resin to obtain the magnetoelectric coupling sensitive element;

[0025] Preparation of magnetoelectric coupling current sensor: fix the magnetoelectric coupling sensitive element at the opening of the open magnetic focusing ring to obtain the magnetoelectric coupling current sensor in the in-plane shear mode.

[0026] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0027] The in-plane shear mode magnetoelectric coupling current sensor based on a full-bridge differential structure provided by the present invention not only has a very high resonant output voltage in the MHz frequency band, but also has a high sensitivity in low-frequency current measurement, thereby being able to improve the measurement signal-to-noise ratio of wide-band current signals.

[0028] By using four piezoelectric materials with the same performance to form a full-bridge differential structure, and outputting the two voltage signals output by the full-bridge structure through an adder, a stable output signal can be obtained while further improving the measurement sensitivity; it can detect wide-band weak currents as low as below 10μA, and standardized output can be achieved by designing a simple amplification and filtering circuit.

[0029] The magnetostrictive phase is a multilayer magnetostrictive material tightly bonded by epoxy resin, thereby reducing the generation of eddy current loss inside the magnetoelectric coupling sensitive element under a high-frequency magnetic field. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other relevant drawings can be obtained based on these drawings without creative work. In the drawings:

[0031] Figure 1 is a schematic structural diagram of a magnetoelectric coupling current sensor according to an embodiment of the present invention;

[0032] Figure 2 is a structural schematic diagram of a magnetoelectric coupling sensitive element according to an embodiment of the present invention;

[0033] Figure 3 is a schematic diagram of the polarization direction of a piezoelectric phase layer in an embodiment of the present invention;

[0034] Figure 4 It is a connection circuit diagram of a piezoelectric phase layer full-bridge differential according to an embodiment of the present invention;

[0035] Figure 5 is a schematic diagram of a working mode of a magnetoelectric coupling sensing element according to an embodiment of the present invention;

[0036] Figure 6 This is a diagram showing the current detection limit result of measuring a 30MHz high frequency current using the magnetoelectric coupling current sensor of the present invention;

[0037] Figure 7 This is a current sensitivity test result diagram of measuring 30MHz high-frequency current using the magnetoelectric coupling current sensor of the present invention.

[0038] The reference numerals and their descriptions are as follows:

[0039] 100, open magnetic concentrator; 200, magnetoelectric coupling sensitive element; 300, wire; 201, magnetostrictive phase layer; 202, piezoelectric phase layer; 203, rigid base; 204, epoxy resin; 210, piezoelectric material. DETAILED DESCRIPTION

[0040] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0041] It should be noted that the terms "including" and "having" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to or inherent to other steps or units of the device.

[0042] The terms used in the various embodiments of the application are only used to describe the purpose of specific embodiments and are not intended to limit the various embodiments of the application. As used herein, the singular form is intended to also include the plural form, unless the context clearly indicates otherwise. Unless otherwise limited, all terms used here (including technical terms and scientific terms) have the same meaning as the meanings commonly understood by ordinary technicians in the field of the various embodiments of the application. The terms (such as the terms defined in the dictionary generally used) will be interpreted as having the same meaning as the contextual meaning in the relevant technical field and will not be interpreted as having an idealized meaning or an overly formal meaning, unless clearly defined in the various embodiments of the application.

[0043] The embodiment of the present invention provides a magnetoelectric coupling current sensor and a preparation method thereof, which is suitable for non-contact current measurement in a wide frequency band and has the advantages of high sensitivity, low cost, high stability, passivity and simple back-end circuit.

[0044] like Figure 1 The structure diagram of a magnetoelectric coupling current sensor according to an embodiment of the present invention is shown, which includes an open magnetic focusing ring 100 and a magnetoelectric coupling sensitive element 200, wherein the magnetoelectric coupling sensitive element 200 is fixed in the opening of the open magnetic focusing ring 100. The open magnetic focusing ring is a high magnetic permeability open magnetic focusing ring, and the opening length is slightly longer than the magnetoelectric coupling sensitive element. The conductor to be measured is placed at the center of the open magnetic focusing ring, and the current to be measured is passed through the conductor to be measured, and the passed current is measured by magnetoelectric induction.

[0045] like Figure 2 The figure shows a schematic diagram of the structure of a magnetoelectric coupling sensitive element 200, including a magnetostrictive phase layer 201, a piezoelectric phase layer 202, a rigid base 203, and a flexible electrode led out from the side of the piezoelectric material that is not connected to the magnetostrictive phase layer and the rigid base. The flexible electrode is connected to the surface marked with "+" and "-" on the piezoelectric material (the back side marked with "+" and "-" is not shown in the figure), that is, each piezoelectric material is connected to 2 flexible electrodes, a total of 8 flexible electrodes, and the 8 flexible electrodes are arranged according to Figure 4 The magnetostrictive phase is magnetized along the length direction, and the piezoelectric phase works in the in-plane shear mode, i.e., d 36Mode. The piezoelectric phase layer 202 includes four piezoelectric materials 210 with the same piezoelectric properties and arranged linearly at equal intervals. The polarization directions of the piezoelectric materials 210 are arranged alternately in the arrangement direction, that is, the arrangement sequence is arranged alternately and at equal intervals according to the positive and negative polarities of the output voltage of the piezoelectric material. The charge output surface of each piezoelectric material 210 is provided with a flexible electrode, and the flexible electrodes are respectively closely attached to the charge output surface of each piezoelectric phase. The flexible electrodes are connected end to end in the arrangement sequence to form a full-bridge differential circuit.

[0046] The upper surface of the piezoelectric phase layer 202 is closely attached to and fixed on the magnetostrictive phase layer 201 , and the lower surface of the piezoelectric phase layer 202 is closely attached to and fixed on the rigid base 203 , ensuring that the piezoelectric phase generates thickness shear strain.

[0047] Furthermore, the magnetostrictive phase layer 201 and the piezoelectric phase layer 202 , as well as the piezoelectric phase layer 202 and the rigid base 203 are tightly bonded by epoxy resin 204 .

[0048] like Figure 3 The figure shows the polarization direction of the piezoelectric phase layer 202, where P represents the polarization direction. The piezoelectric material 210 is in the shape of a regular hexahedron, and the polarization direction P is along its body diagonal. In the linear arrangement direction, two polarization directions in opposite directions are alternately arranged, so that the flexible electrode tails drawn from the charge output surface of the piezoelectric material are connected to form a full-bridge differential structure, see Figure 4 The full-bridge differential structure connection circuit diagram of the piezoelectric phase layer is shown, and R1, R2, R3, and R4 respectively represent the equivalent resistances of four piezoelectric materials.

[0049] like Figure 1 , Figure 5 As shown, Figure 5 The working mode diagram of the magnetoelectric coupling sensitive element. During measurement, the current to be measured passes through the center of the magnetic ring through the through-core wire. According to Faraday's law of electromagnetic induction, a circular magnetic field is generated around the through-core wire, and it is gathered at the opening of the magnetic ring to form a uniform magnetic field. Based on the magnetoelectric coupling effect, the magnetostrictive phase of the magnetoelectric coupling sensitive element is magnetized along the magnetic field direction, and the high-frequency magnetic field signal at the opening of the magnetic ring generates mechanical expansion and contraction of the same frequency, thereby driving the piezoelectric phase close to it to generate in-plane shear vibration, and outputting a voltage signal of the same frequency on the lead-out flexible electrode, completing the non-contact sensing of current-magnetic field-mechanical vibration-voltage; and the connection of the four piezoelectric materials through a full-bridge differential structure can further improve the sensitivity of current measurement.

[0050] In one embodiment, the two output voltage signals of the full-bridge differential circuit are connected to an adder, see Figure 4 As shown in the figure, after the adder output, a stable voltage signal can be obtained while further improving the measurement sensitivity, and a wide-band weak current as low as 10μA can be detected.

[0051] Furthermore, by connecting an amplifying and filtering circuit to the output end of the adder, a stable standardized output can be obtained.

[0052] In one embodiment, the magnetostrictive phase layer includes at least two layers of magnetostrictive thin sheets, and adjacent magnetostrictive thin sheets are bonded and fixed by epoxy resin, thereby reducing the generation of eddy current loss inside the magnetoelectric coupling sensitive element under high-frequency magnetic field.

[0053] The magnetostrictive material used in the magnetostrictive phase can be one of Metglas, nickel manganese gallium alloy (Ni2MnGa), nickel iron oxide (NiFe2O4), terbium dysprosium iron [Terfenol-D (Tb0.27-0.30Dy0.73-0.70Fe1.90-1.95)], cobalt iron oxide (CoFe2O4), or one of the magnetostrictive composite materials formed by combining the above magnetostrictive materials with polymers.

[0054] Preferably, in the magnetostrictive phase layer composed of multiple layers of magnetostrictive sheets, the thickness of a single layer is 20 μm to 300 μm, the length is 5 to 100 mm, and the width is 2 to 5 mm.

[0055] Furthermore, the piezoelectric material used in the piezoelectric phase is one of AlN, quartz, LiNbO3, BaTiO3, ZnO, Pb(Zr,Ti)O3, Pb(Mg,Nb)O3-PbTiO3, Pb(Zn,Nb)O3-PbTiO3, Pb(Ni,Nb)O3-Pb(Zr,Ti)O3 or BiScO3-PbTiO3.

[0056] Preferably, the piezoelectric material has a thickness of 0.1 to 5 mm, a length of 1 to 10 mm, and a width of 2 to 5 mm, and the width of the piezoelectric phase is consistent with that of the magnetostrictive phase.

[0057] Furthermore, the base material of the flexible electrode is one of polyethylene terephthalate PET, polydimethylsiloxane PDMS, polyethylene PE, polyvinyl chloride PVC or polypropylene PP, and the conductive material of the flexible electrode is one of Au, Ag, Al, Cu, Pt or Ni.

[0058] Furthermore, the material of the magnetic focusing ring is one of ferrite, Permalloy, amorphous alloy and the like.

[0059] Preferably, the outer diameter of the magnetic focusing ring is 30-100 mm, more preferably 50 mm; the inner diameter is 25-95 mm, more preferably 40 mm; the thickness is 5-30 mm, more preferably 12 mm.

[0060] The material of the rigid base should be a diamagnetic material with a relatively large elastic modulus, preferably one of alloys such as brass, copper, phosphor bronze, aluminum alloy, titanium alloy, or one of glass and ceramics.

[0061] A second aspect of the present invention provides a method for preparing the magnetoelectric coupling current sensor of the present invention, comprising:

[0062] Preparation of magnetostrictive phase layer: processing magnetostrictive material into magnetostrictive thin sheets, bonding multiple layers of magnetostrictive material with epoxy resin and leaving them to stand at room temperature to obtain magnetostrictive phase;

[0063] Preparation of piezoelectric phase layer: cutting the piezoelectric material into blocks, ultrasonically cleaning with ultrapure water, selecting four piezoelectric materials with the same performance parameters, making silver electrodes on two opposite surfaces in the width direction of each piezoelectric material (i.e., the width direction of the magnetostrictive phase), and polarizing along the body diagonal direction, the surface on which the silver electrode is made is the side that is not connected to the magnetostrictive phase and the rigid base; arranging the four piezoelectric materials linearly in an alternating and equidistant manner according to the polarization direction, connecting the silver electrodes end to end in the arrangement order, forming a full-bridge differential structure, and obtaining a piezoelectric phase layer;

[0064] Preparation of magnetoelectric coupling sensitive element: the upper surface of the piezoelectric phase layer is tightly bonded to the magnetostrictive phase layer through epoxy resin, and the lower surface is tightly bonded to the rigid base through epoxy resin to obtain the magnetoelectric coupling sensitive element;

[0065] Preparation of magnetoelectric coupling current sensor: fix the magnetoelectric coupling sensitive element at the opening of the open magnetic focusing ring to obtain the magnetoelectric coupling current sensor in the in-plane shear mode.

[0066] In the above method, the materials and dimensions of the magnetostrictive phase layer, piezoelectric phase layer, rigid base and open magnetic focusing ring can refer to the above embodiments. The flexible electrode can be formed on the upper and lower surfaces of each piezoelectric material by electroplating, silver paste annealing, etc.

[0067] like Figure 6 , Figure 7 Shown is a current detection limit curve and a current sensitivity test curve obtained by measuring and testing a 30MHz high-frequency current using the magnetoelectric coupling current sensor in the above embodiment of the present invention made by the above preparation method. The test has verified that the magnetoelectric coupling current sensor proposed in the present invention has the advantages of wide-band current measurement and high sensitivity in the MHz frequency band.

[0068] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A magnetoelectric coupling current sensor, characterized in that: include: Open magnetic focusing ring (100); A magnetoelectric coupling sensitive element (200) comprises a magnetostrictive phase layer (201), a piezoelectric phase layer (202) and a rigid base (203) connected from top to bottom; The piezoelectric phase layer (202) comprises four piezoelectric materials (210) with the same piezoelectric properties and arranged linearly at equal intervals, the polarization directions of the piezoelectric materials (210) being arranged alternately in the arrangement direction, and a flexible electrode being arranged on the charge output surface of each of the piezoelectric materials (210), and the flexible electrodes being connected end to end in the arrangement order to form a full-bridge differential circuit; The magnetoelectric coupling sensitive element (200) is arranged at the opening of the open magnetic focusing ring (100) to form a magnetoelectric coupling current sensor in an in-plane shear mode.

2. The magnetoelectric coupling current sensor according to claim 1, characterized in that: The magnetostrictive phase layer (201) and the piezoelectric phase layer (202), and the piezoelectric phase layer (202) and the rigid base (203) are tightly bonded via epoxy resin (204).

3. The magnetoelectric coupling current sensor according to claim 1, characterized in that: The two output voltage signals of the full-bridge differential circuit are connected to an adder, and the output end of the adder is connected to an amplifying and filtering circuit to obtain a stable standardized voltage output.

4. The magnetoelectric coupling current sensor according to claim 1, characterized in that: The piezoelectric material (210) is in a hexahedral shape, and the polarization direction is along the diagonal line of the body.

5. The magnetoelectric coupling current sensor according to claim 4, characterized in that: The piezoelectric material (210) is made of AlN, quartz, LiNbO3, BaTiO3, ZnO, Pb(Zr, Ti)O3, Pb(Mg, Nb)O3-PbTiO3, Pb(Zn, Nb)O3-PbTiO3, Pb(Ni, Nb)O3-Pb(Zr, Ti)O3 or BiScO3-PbTiO3.

6. The magnetoelectric coupling current sensor according to claim 1, characterized in that: The magnetostrictive phase layer (201) comprises at least two layers of magnetostrictive thin sheets, and the magnetostrictive thin sheets are bonded together by epoxy resin.

7. The magnetoelectric coupling current sensor according to claim 6, characterized in that: The material of the magnetostrictive sheet is one of Metglas, nickel-manganese-gallium alloy, nickel-iron oxide, terbium-dysprosium-iron, and cobalt-iron oxide, or a composite material of one of Metglas, nickel-manganese-gallium alloy, nickel-iron oxide, terbium-dysprosium-iron, and cobalt-iron oxide and a polymer.

8. The magnetoelectric coupling current sensor according to claim 1, characterized in that: The material of the rigid base (203) is brass, copper, phosphor bronze, aluminum alloy, titanium alloy, glass or ceramic.

9. The magnetoelectric coupling current sensor according to claim 1, characterized in that: The open magnetic focusing ring (100) has an outer diameter of 30 to 100 mm, an inner diameter of 25 to 95 mm, and a diameter of 5 to 30 mm.

10. A preparation method for preparing the magnetoelectric coupling current sensor according to any one of claims 1 to 9, characterized in that: include: Preparation of magnetostrictive phase layer: processing magnetostrictive material into magnetostrictive thin sheets, bonding multiple layers of magnetostrictive material with epoxy resin and leaving them to stand at room temperature to obtain magnetostrictive phase layer; Preparation of piezoelectric phase layer: cutting the piezoelectric material into blocks, ultrasonically cleaning with ultrapure water, selecting four piezoelectric materials with the same performance parameters, making silver electrodes on two opposite surfaces in the width direction of each piezoelectric material, and polarizing along the body diagonal direction; arranging the four piezoelectric materials linearly in an alternating and equidistant manner according to the polarization direction, connecting the silver electrodes end to end in the order of arrangement to form a full-bridge differential structure, and obtaining the piezoelectric phase layer; Preparation of magnetoelectric coupling sensitive element: the upper surface of the piezoelectric phase layer is tightly bonded to the magnetostrictive phase layer through epoxy resin, and the lower surface is tightly bonded to the rigid base through epoxy resin to obtain the magnetoelectric coupling sensitive element; Preparation of magnetoelectric coupling current sensor: fix the magnetoelectric coupling sensitive element at the opening of the open magnetic focusing ring to obtain the magnetoelectric coupling current sensor in the in-plane shear mode.

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