Current sensor and sensing equipment

Abstract

The invention discloses a current sensor and sensing equipment, and relates to the technical field of current measurement. The current sensor comprises a magnetism gathering ring unit which is provided with at least one opening air gap and a first channel for accommodating a wire; the magnetic resistance sensing unit is used for collecting magnetic field signals around the opening air gap; the shielding unit comprises at least two shielding shells, is used for surrounding the magnetism gathering ring unit and is provided with an annular opening close to the inner ring wall of the magnetism gathering ring unit so as to shield interference signals around an opening air gap; and the signal processing unit is electrically coupled with the magnetic resistance sensing unit through the annular opening and is used for processing an output signal of the magnetic resistance sensing unit. By improving the structure of the shielding unit, the shielding effect of the current sensor on interference signals in a strong magnetic field environment is greatly improved, and the current sensor has the advantages of being simple in structure and easy to implement.

Description

Technical Field

[0001] The present invention relates to the technical field of current detection, and in particular to a current sensor and a sensing device. Background Art

[0002] A current sensor is a device for detecting current. It is generally used in actual current measurement and protection systems, such as photovoltaics, wind power, electricity, smart grids, railway electromechanical, aerospace, new energy vehicles and other fields. As the main detection element, the current sensor plays a vital role in ensuring the safety and stability of the system.

[0003] In order to achieve non-contact current measurement, the wire is usually passed through a magnetic ring, and the magnetic field around the wire is sensed by the magnetoresistive element in the air gap of the magnetic ring. However, when there are other magnetic field signals in the environment, the magnetic field signal sensed by the magnetoresistive element will be disturbed, affecting the accuracy of current detection and easily causing misjudgment. Summary of the invention

[0004] The main purpose of the present invention is to provide a current sensor and a sensing device, aiming to solve the technical problem in the prior art that the environmental magnetic field has a great interference on the detection of the current sensor.

[0005] To achieve the above-mentioned object, a first aspect of the present invention provides a current sensor. The current sensor comprises: A magnetic concentrating ring unit, which is provided with at least one open air gap and has a first channel for accommodating a wire; A magnetoresistive sensing unit, which is used to collect magnetic field signals around the open air gap; A shielding unit, comprising at least two shielding shells, which are used to surround the magnetic focusing ring unit and have an annular opening close to the inner ring wall of the magnetic focusing ring unit to shield interference signals around the magnetic focusing ring unit; A signal processing unit is electrically coupled to the magnetoresistive sensing unit via the annular opening, and is used for processing an output signal of the magnetoresistive sensing unit.

[0006] According to some embodiments of the present invention, the magnetic focusing ring unit includes an annular base, a first magnetic focusing ring and a second magnetic focusing ring; the annular base includes a first receiving seat for receiving the first magnetic focusing ring, a second receiving seat for receiving the second magnetic focusing ring, and a first air gap position and a second air gap position located between the first receiving seat and the second receiving seat; The magnetoresistive sensor unit comprises at least one magnetoresistive sensor mounting seat and a magnetoresistive sensor element accommodated in the magnetoresistive sensor mounting seat, wherein the magnetoresistive sensor element has a Wheatstone bridge structure; The at least one magnetoresistive sensor mounting seat is disposed at the first air gap position and / or the second air gap position.

[0007] According to some embodiments of the present invention, the at least two shielding shells include a first shielding shell, the first shielding shell is used to surround the annular base and has a first annular opening close to the annular base; The first shielding shell comprises a first shielding base and a first shielding cover; the first shielding base surrounds the bottom, lower side wall and lower inner ring wall of the annular base; the first shielding cover surrounds the top, upper side wall and upper inner ring wall of the annular base; the first annular opening is located between the lower inner ring wall and the upper inner ring wall; The at least two shielding shells further include a second shielding shell, which is used to surround the first shielding shell and has a second annular opening close to the first annular opening; the second shielding shell is separated from the first shielding shell.

[0008] According to some embodiments of the present invention, the shielding unit further comprises a first insulating shell, the first insulating shell is used to surround the first shielding shell and has a third annular opening close to the first annular opening; The second shielding shell is used to surround the first insulating shell and has a second annular opening close to the third annular opening.

[0009] According to some embodiments of the present invention, the magnetic focusing ring unit comprises a left annular base, a right annular base, a first magnetic focusing ring and a second magnetic focusing ring; the left annular base and the right annular base form a first annular structure, and the first annular structure has the at least one open air gap and the first channel that can be opened and closed; The left annular base includes a first receiving seat for receiving the first magnetic focusing ring and a U-shaped bearing seat arranged along the edge of the left annular base; the U-shaped bearing seat is close to the annular opening; The right annular base includes a second receiving seat for receiving the second magnetic focusing ring; The magnetoresistive sensing unit includes a U-shaped mounting seat and magnetoresistive sensing elements accommodated on both sides of the U-shaped mounting seat, and the magnetoresistive sensing element has a Wheatstone bridge structure.

[0010] According to some embodiments of the present invention, the at least two shielding shells include a first left shielding shell and a first right shielding shell, the first left shielding shell is used to surround the left annular base and has a first left annular opening close to the left annular base; the first right shielding shell is used to surround the right annular base and has a first right annular opening close to the right annular base; the first left shielding shell and the first right shielding shell form a second annular structure surrounding the first annular structure; The first left shielding shell comprises a first left shielding base and a first left shielding cover; the first left shielding base surrounds the first left bottom, the first left lower side wall and the first left lower inner ring wall of the left annular base; the first left shielding cover surrounds the first left top, the first left upper side wall and the first left upper inner ring wall of the left annular base; the first left ring opening is located between the left lower inner ring wall and the left upper inner ring wall; the first right ring opening is located between the right lower inner ring wall and the right upper inner ring wall; The at least two shielding shells also include a second left shielding shell and a second right shielding shell; the second left shielding shell and the second right shielding shell form a third annular structure surrounding the second annular structure; the second left shielding shell and the second right shielding shell are respectively used to surround the first left shielding shell and the first right shielding shell and have a second left annular opening close to the first left annular opening and a second right annular opening close to the first right annular opening; the second left shielding shell and the first left shielding shell are separated from each other; the second right shielding shell and the first right shielding shell are separated from each other.

[0011] According to some embodiments of the present invention, the shielding unit further includes a first left insulating shell and a first right insulating shell; the first left insulating shell and the first right insulating shell form a fourth annular structure; the first left insulating shell and the first right insulating shell are respectively used to surround the first left shielding shell and the first right shielding shell and have a third left annular opening close to the left annular opening and a third right annular opening close to the first right annular opening; The second left shielding shell and the second right shielding shell are used to surround the first left insulating shell and the first right insulating shell respectively and have a second left annular opening close to the third left annular opening and a second right annular opening close to the third right annular opening.

[0012] According to some embodiments of the present invention, the current path sensor further comprises an openable and closable unit, the openable and closable unit comprising a left shell, a right shell, and an openable and closable structure respectively connected to the left shell and the right shell; the openable and closable structure is used to make the left shell and the right shell form a closed fifth annular structure; The left shell and the right shell respectively include a first elastic body and a second elastic body, which are used to reduce the gap between the left annular base and the right annular base in the fifth annular structure.

[0013] According to some embodiments of the present invention, the material of the at least two shielding shells is a soft magnetic material; Preferably, the soft magnetic material is Permalloy or nanocrystal.

[0014] To achieve the above object, a second aspect of the present invention provides a sensing device. The sensing device includes a current sensor, and the current sensor is the above current sensor.

[0015] Therefore, compared with the prior art, the present invention has the following beneficial effects: The current sensor disclosed in the present invention includes a magnetic ring unit, which is provided with at least one open air gap and has a first channel for accommodating a wire; a magnetoresistive sensing unit, which is used to collect magnetic field signals around the open air gap; a shielding unit, which includes at least two shielding shells, which are used to surround the magnetic ring unit and have an annular opening close to the inner ring wall of the magnetic ring unit to shield interference signals around the open air gap; and a signal processing unit, which is electrically coupled to the magnetoresistive sensing unit through the annular opening and is used to process the output signal of the magnetoresistive sensing unit. The present invention greatly improves the shielding effect of the current sensor on interference signals in a strong magnetic field environment by improving the structure of the shielding unit, and has the beneficial effects of simple structure and easy implementation. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0017] Figure 1 is a first structural schematic diagram of a current sensor according to an embodiment of the present invention; Figure 2 is a cross-sectional schematic diagram of a first shielding shell, a second shielding shell and an insulating shielding shell in a shielding unit according to an embodiment of the present invention; Figure 3 is a second structural schematic diagram of a current sensor according to an embodiment of the present invention; Figure 4 Schematic diagram of the structure of the magnetic focusing ring unit and the magnetic resistance sensor unit in the embodiment of the present invention; Figure 5 It is another structural schematic diagram of the magnetic focusing ring unit and the magnetic resistance sensor unit in another embodiment of the present invention; Figure 6 FIG. 4 is a schematic diagram of the structure of a current sensor in another embodiment of the present invention.

[0018] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0021] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0022] A current sensor is a device for detecting current. It is generally used in actual current measurement and protection systems, such as photovoltaics, wind power, electricity, smart grids, railway electromechanical, aerospace, new energy vehicles and other fields. As the main detection element, the current sensor plays a vital role in ensuring the safety and stability of the system.

[0023] In order to achieve non-contact current measurement, the wire is usually passed through a magnetic ring, and the magnetic field around the wire is sensed by the magnetoresistive element in the air gap of the magnetic ring. However, when there are other magnetic field signals in the environment, the magnetic field signal sensed by the magnetoresistive element will be disturbed, affecting the accuracy of current detection and easily causing misjudgment.

[0024] Therefore, an embodiment of the present invention provides a current sensor, aiming to solve the technical problem in the prior art that the ambient magnetic field has a significant interference on the detection of the current sensor.

[0025] like Figure 1-4As shown, the current sensor of the embodiment of the present invention comprises a magnetic ring unit 100, a magnetoresistive sensing unit 200, a shielding unit 300 and a signal processing unit 400. The magnetoresistive sensing unit 200 is located at the open air gap position of the magnetic ring unit; the magnetoresistive sensing unit 200 passes through the inner ring wall of the shielding unit 300 and passes through the magnetic ring unit to be electrically coupled with the external signal processing unit 400.

[0026] The magnetic focusing ring unit 100 of the embodiment of the present invention is annular in structure, provided with two open air gaps, and has a first channel for accommodating a wire. The open air gap is used to accommodate a magnetic resistance sensor unit, and the magnetic focusing ring unit is used to enhance the magnetic field strength at the open air gap position.

[0027] It should be understood that the number of the open air gaps is not limited to two, and may be 1, 3 or more depending on the situation, and is not limited here.

[0028] The magnetic focusing ring unit 100 of the embodiment of the present invention includes two magnetic focusing rings: a first magnetic focusing ring 110 and a second magnetic focusing ring 120. The two magnetic focusing rings form an annular structure, and the annular structure forms a circular first channel.

[0029] It should be understood that the annular structure may also be an elliptical or other closed-loop channel.

[0030] The magnetoresistive sensing unit 200 of the embodiment of the present invention is used to collect magnetic field signals around an open air gap. The magnetoresistive sensing unit has a Wheatstone bridge structure. The magnetoresistive element in the magnetoresistive sensing unit has a resistance that varies with the magnetic field strength under a magnetic field. The magnetic field information of the position of the open air gap is determined by the differential signal output by the magnetoresistive sensing unit, and then the load current information of the conductor is determined.

[0031] It should be understood that the magnetoresistive element is an element with magnetoresistive effect, which may be an anisotropic magnetoresistive element, a giant magnetoresistive element, a tunneling magnetoresistive element or other magnetoresistive elements. The magnetoresistive element can sense a magnetic field in a first direction in an open air gap.

[0032] The signal processing unit 400 of the embodiment of the present invention is electrically coupled to the magnetoresistive sensing unit 200 at the open air gap position, and is used to process the differential signal output by the magnetoresistive sensing unit to determine the load current of the wire.

[0033] Specifically, the signal processing unit 400 receives the differential signal output by the magnetoresistive sensing units located at the two open air gap positions, and determines the load current information of the conductor according to the differential signal.

[0034] It should be understood that the differential signal output by the magnetoresistive sensing unit is related to the magnetic field strength at the open air gap position. If the magnetic field strength at the open air gap position exceeds the detection range of the magnetoresistive sensing unit, the signal processing unit 400 cannot determine the load current information of the conductor through the differential signal. The magnetic field strength is not specifically limited here.

[0035] The shielding unit 300 of the embodiment of the present invention includes two shielding shells: a first shielding shell 310 and a second shielding shell 320, which are used to surround the magnetic focusing ring unit 100, and have an annular opening 340 close to the inner ring wall of the magnetic focusing ring unit 100 to shield the interference signal around the magnetic focusing ring unit 100. The first shielding shell and the second shielding shell only expose the position of the annular opening 340.

[0036] It should be understood that there are at least two shielding shells. Generally speaking, the more shielding shells there are, the stronger the shielding effect is. However, the setting of the shielding shells is likely to increase the volume and weight of the current sensor. Therefore, the specific setting depends on the actual situation. The material of the shielding shell is a soft magnetic material, which can be Permalloy, nanocrystalline or other materials, which are not specifically limited here.

[0037] Specifically, the shielding unit 300 includes a first shielding shell 310 with an annular structure, a second shielding shell 320 with an annular structure, and a first insulating shell 330 located between the first shielding shell 310 and the second shielding shell 320; the first insulating shell 330 is used to separate the first shielding shell 310 and the second shielding shell 320 to avoid direct contact between them, thereby weakening the shielding effect.

[0038] Further, the first shielding shell 310 surrounds the magnetic ring unit 100; the first insulating shell 330 surrounds the first shielding shell 310; and the second shielding shell 320 surrounds the first insulating shell 330. The inner ring walls of the first shielding shell 310, the second shielding shell 320 and the first insulating shell 330 respectively have a first annular opening, a second annular opening and a third annular opening corresponding to the annular opening. The magnetoresistive sensor unit 200 can pass through the first annular opening, the second annular opening and the third annular opening, and thus there is no need to open a through hole at other positions of the magnetic ring unit 100, thereby preventing the external magnetic field from interfering with the normal magnetic field induction of the magnetoresistive sensor unit through the through hole, thereby reducing the measurement error of the magnetoresistive sensor unit.

[0039] Therefore, the embodiment of the present invention further eliminates the interfering magnetic field outside the magnetic ring unit that is unfavorable to the induction of the magnetoresistive sensor unit through the annular opening 340 in the inner ring wall of the shielding unit 300 and the double-layer shielding shell structure, which can be helpful in restoring the magnetic field conditions of the first channel itself and improving the current collection accuracy of the magnetoresistive sensor unit.

[0040] like Figure 4As shown, the magnetic focusing ring unit 100 of the embodiment of the present invention includes, in addition to the first magnetic focusing ring 110 and the second magnetic focusing ring 120, an annular base 130 for accommodating the first magnetic focusing ring and the second magnetic focusing ring. The annular base includes a first accommodating seat for accommodating the first magnetic focusing ring 110, a second accommodating seat for accommodating the second magnetic focusing ring 120, and also includes a first air gap position for accommodating the first magnetoresistive element 240 in the magnetoresistive sensor unit and a second air gap position for accommodating the second magnetoresistive element 250 in the magnetoresistive sensor unit.

[0041] It should be understood that since the first magnetic focusing ring and the second magnetic focusing ring of the current sensor are generally provided with coils wound thereon to realize functions such as demagnetization and self-detection, the first receiving seat of the annular base 130 can also be used to receive the first magnetic focusing ring wound with the coils, and the second receiving seat can also be used to receive the second magnetic focusing ring wound with the coils.

[0042] The magnetoresistive sensor unit 200 of the embodiment of the present invention includes two magnetoresistive sensor mounting seats and magnetoresistive sensor elements located at the magnetoresistive sensor mounting seats. The first magnetoresistive sensor element in the magnetoresistive sensor element is fixed at the first air gap position through the first magnetoresistive sensor mounting seat, and the second magnetoresistive sensor element is fixed at the second air gap position through the second magnetoresistive sensor mounting seat. The magnetoresistive sensor mounting seat can be U-shaped and can fix the position of the magnetoresistive sensor element by clamping the end position of the first magnetic focusing ring or the second magnetic focusing ring.

[0043] It should be understood that the magnetoresistive sensor mounting base should be insensitive to the magnetic field, and its structure is not limited to a U-shape. For example, it can be placed flat at the first air gap position and the second air gap position, which is not limited here.

[0044] The first shielding shell 310 of the embodiment of the present invention includes two upper and lower parts: a first shielding base 314 and a first shielding cover 313. The first shielding base 314 and the first shielding cover 313 are nested and fixed with the first magnetic focusing ring and the second magnetic focusing ring through the annular base 130. The second shielding shell 320 includes two upper and lower parts: a second shielding base 324 and a second shielding cover 323. The second shielding base 324 and the second shielding cover 323 are nested and fixed with the first shielding base 314 and the first shielding cover 313 through the insulating base 334 and the insulating cover 333, respectively. Furthermore, as Figure 3 As shown, the second shielding base 324 and the second shielding cover in the current sensor form a circular ring structure, and the inner ring wall of the circular ring structure has a circular opening 340 .

[0045] The first shielding base 314 of the embodiment of the present invention is used to surround the bottom, lower side wall and lower inner ring wall of the annular base 130; the first shielding cover 313 is used to surround the top, upper side wall and upper inner ring wall of the annular base 130, and a first annular opening is provided between the lower inner ring wall and the upper inner ring wall.

[0046] The insulating base 334 of the embodiment of the present invention is used to include the bottom, lower side wall and lower inner ring wall of the first shielding shell 310, and the insulating cover 333 is used to surround the top, upper side wall and upper inner ring wall of the first shielding shell 310, and form a third annular opening between the lower inner ring wall and the upper inner ring wall. The third annular opening is close to the first annular opening.

[0047] The second shielding base 324 of the embodiment of the present invention is used to surround the bottom, lower side wall and lower inner ring wall of the first insulating shell 330; the second shielding cover 323 is used to surround the top, upper side wall and upper inner ring wall of the first insulating shell 330, and a second annular opening is provided between the lower inner ring wall and the upper inner ring wall. The second annular opening is close to the third annular opening.

[0048] Therefore, the annular base of the embodiment of the present invention is respectively nested by the first shielding base and the first shielding cover; the first shielding base is nested by the insulating base in the first insulating shell, and the first shielding cover is nested by the insulating cover in the first insulating shell; the second shielding base is nested by the insulating base in the first insulating shell, and the second shielding cover is nested by the insulating cover in the first insulating shell. Then the magnetic focusing ring unit is fixedly connected to the shielding unit.

[0049] In another embodiment of the present invention, Figure 5-6 As shown, the current sensor is openable and closable. The annular base 130 of the current sensor includes a left annular base 132 and a right annular base 131. The left annular base 132 and the right annular base 131 form a first annular structure; the first annular structure has two open air gaps and an openable and closable first channel.

[0050] The left annular base 132 is used to accommodate the first magnetic focusing ring 110, and the right annular base 132 is used to accommodate the second magnetic focusing ring 120. The magnetoresistive element in the magnetoresistive sensor unit 200 is fixed to the inner ring wall of the left annular base and the first air gap position and the second air gap position through the magnetoresistive sensor mounting seat 230.

[0051] like Figure 5 As shown, the magnetoresistive sensor mounting base 230 is U-shaped, including a first connecting bar and a second connecting bar located at two air gap positions, and an arc-shaped connecting plate connecting the first connecting bar and the second connecting bar. The magnetoresistive sensor element can be flatly fixed on the first connecting bar and the second connecting bar.

[0052] It should be understood that when the magnetoresistive sensing unit 200 is disposed at only one air gap position, the magnetoresistive sensing element may be fixed to the first connecting bar or the second connecting bar, which is not specifically limited herein.

[0053] In the embodiment of the present invention, the first shielding shell in the shielding unit includes a first left shielding shell and a first right shielding shell, the second shielding shell includes a second left shielding shell and a second right shielding shell, and the first insulating shell includes a first left insulating shell and a first right insulating shell.

[0054] The first left shielding shell is used to surround the left annular base and has a first left annular opening close to the left annular base; the first right shielding shell is used to surround the right annular base and has a first right annular opening close to the right annular base. The first left shielding shell and the first right shielding shell form a second annular structure surrounding the first annular structure.

[0055] The first left insulating shell is used to surround the first left shielding shell and has a third left annular opening close to the first left shielding shell; the right shielding shell is used to surround the first right shielding shell and has a third right annular opening close to the first right annular opening, and the first left insulating shell and the first right insulating shell form a fourth annular structure surrounding the second annular structure; The second left shielding shell is used to surround the first left insulating shell and has a second left annular opening close to the third left annular opening; the second right shielding shell is used to surround the first right insulating shell and has a second right annular opening close to the third right annular opening, and the second left shielding shell and the second right shielding shell form a third annular structure surrounding the fourth annular structure.

[0056] In order not to affect the measurement effect, the first left shielding shell and the first right shielding shell, the second left shielding shell and the second right shielding shell, the first left insulating shell and the first right insulating shell do not surround the end surfaces of the first magnetic focusing ring and the second magnetic focusing ring.

[0057] In the embodiment of the present invention, in order to make the left annular base fixedly connected to the shielding unit, the first left shielding shell surrounds the left annular base, the first left insulating shell surrounds the first left shielding shell, and the second left shielding shell surrounds the first left insulating shell. Furthermore, the left annular base is fixed to the left shielding assembly in the shielding unit.

[0058] To make the right annular base fixedly connected to the shielding unit, the first right shielding shell surrounds the right annular base, the first right insulating shell surrounds the first right shielding shell, and the second right shielding shell surrounds the first right insulating shell. Furthermore, the right annular base is fixed to the right shielding assembly in the shielding unit.

[0059] After multiple tests, it was found that when the left shielding assembly and the right shielding assembly are as close as possible and the gap between the first magnetic focusing ring and the second magnetic focusing ring is reduced, the current measurement achieved by the magnetoresistive sensing unit has higher accuracy.

[0060] In the embodiment of the present invention, in order to reduce the distance between the left shielding component and the right shielding component, as shown in FIG. Figure 6 As shown, the current sensor further includes an openable and closable unit, which includes a left housing (401 and 403), a right housing (402 and 404) and an openable and closable structure (not shown) connected to the left housing and the right housing. The openable and closable structure is used to make the left housing and the right housing form a closed fifth annular structure.

[0061] The left shell is fixed up and down by the left base 401 and the left cover 403 and the rivets arranged between the left base 401 and the left cover 403, and the gap between the left annular base 132 and the right annular base 131 is reduced in the closed state by a first elastomer (not shown) arranged between the outer wall of the left shielding assembly and the left base 401.

[0062] The right shell is fixed up and down by the right base 402 and the right cover 404 and rivets arranged between the right base 402 and the right cover 404, and the gap between the left annular base and the right annular base is reduced in the closed state by a second elastomer (not shown) arranged between the outer wall of the right shielding unit and the right base 402.

[0063] It should be understood that the left shell and the right shell should be insensitive to the external magnetic field to avoid interference with the current measurement. At the same time, the left shell and the right shell may or may not include an inner shell covering the inner ring wall of the shielding unit, which is not limited here.

[0064] To achieve the above objective, an embodiment of the present invention further discloses a sensing device.

[0065] The sensing device comprises a current sensor, which is any one of the current sensors described above.

[0066] The sensor device in the embodiment of the present invention can at least be used for current collection.

[0067] Furthermore, the sensor device according to the embodiment of the present invention can also be used for functions such as power collection and power consumption collection.

[0068] In summary, the current sensor provided by the embodiment of the present invention includes a magnetic ring unit, which is provided with at least one open air gap and has a first channel for accommodating a wire; a magnetoresistive sensing unit, which is used to collect magnetic field signals around the open air gap; a shielding unit, which includes at least two shielding shells, which are used to surround the magnetic ring unit and have an annular opening close to the inner ring wall of the magnetic ring unit to shield interference signals around the open air gap; a signal processing unit, which is electrically coupled to the magnetoresistive sensing unit through the annular opening, and is used to process the output signal of the magnetoresistive sensing unit. By improving the structure of the shielding unit, the shielding effect of the current sensor on interference signals in a strong magnetic field environment is greatly improved, and it has the beneficial effects of simple structure and easy implementation.

[0069] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A current sensor, characterized in that: include: A magnetic concentrating ring unit, which is provided with at least one open air gap and has a first channel for accommodating a wire; A magnetoresistive sensing unit, which is used to collect magnetic field signals around the open air gap; A shielding unit, comprising at least two shielding shells, which are used to surround the magnetic focusing ring unit and have an annular opening close to the inner ring wall of the magnetic focusing ring unit to shield interference signals around the magnetic focusing ring unit; A signal processing unit is electrically coupled to the magnetoresistive sensing unit via the annular opening, and is used for processing an output signal of the magnetoresistive sensing unit.

2. The current sensor according to claim 1, characterized in that: The magnetic focusing ring unit comprises an annular base, a first magnetic focusing ring and a second magnetic focusing ring; the annular base comprises a first receiving seat for receiving the first magnetic focusing ring, a second receiving seat for receiving the second magnetic focusing ring, and a first air gap position and a second air gap position located between the first receiving seat and the second receiving seat; The magnetoresistive sensor unit comprises at least one magnetoresistive sensor mounting seat and a magnetoresistive sensor element accommodated in the magnetoresistive sensor mounting seat, wherein the magnetoresistive sensor element has a Wheatstone bridge structure; The at least one magnetoresistive sensor mounting seat is disposed at the first air gap position and / or the second air gap position.

3. The current sensor according to claim 2, characterized in that: The at least two shielding shells include a first shielding shell, the first shielding shell is used to surround the annular base and has a first annular opening close to the annular base; The first shielding shell comprises a first shielding base and a first shielding cover; the first shielding base surrounds the bottom, lower side wall and lower inner ring wall of the annular base; the first shielding cover surrounds the top, upper side wall and upper inner ring wall of the annular base; the first annular opening is located between the lower inner ring wall and the upper inner ring wall; The at least two shielding shells further include a second shielding shell, which is used to surround the first shielding shell and has a second annular opening close to the first annular opening; the second shielding shell is separated from the first shielding shell.

4. The current sensor according to claim 3, characterized in that: The shielding unit further comprises a first insulating shell, the first insulating shell is used to surround the first shielding shell and has a third annular opening close to the first annular opening; The second shielding shell is used to surround the first insulating shell and has a second annular opening close to the third annular opening.

5. The current sensor according to claim 2, characterized in that: The magnetic focusing ring unit comprises a left annular base, a right annular base, a first magnetic focusing ring and a second magnetic focusing ring; the left annular base and the right annular base form a first annular structure, and the first annular structure has at least one open air gap and the first channel that can be opened and closed; The left annular base includes a first receiving seat for receiving the first magnetic focusing ring and a U-shaped bearing seat arranged along the edge of the left annular base; the U-shaped bearing seat is close to the annular opening; The right annular base includes a second receiving seat for receiving the second magnetic focusing ring; The magnetoresistive sensing unit includes a U-shaped mounting seat and magnetoresistive sensing elements accommodated on both sides of the U-shaped mounting seat, and the magnetoresistive sensing element has a Wheatstone bridge structure.

6. The current sensor according to claim 5, characterized in that: The at least two shielding shells include a first left shielding shell and a first right shielding shell, wherein the first left shielding shell is used to surround the left annular base and has a first left annular opening close to the left annular base; the first right shielding shell is used to surround the right annular base and has a first right annular opening close to the right annular base; the first left shielding shell and the first right shielding shell form a second annular structure surrounding the first annular structure; The first left shielding shell comprises a first left shielding base and a first left shielding cover; the first left shielding base surrounds the first left bottom, the first left lower side wall and the first left lower inner ring wall of the left annular base; the first left shielding cover surrounds the first left top, the first left upper side wall and the first left upper inner ring wall of the left annular base; the first left ring opening is located between the left lower inner ring wall and the left upper inner ring wall; the first right ring opening is located between the right lower inner ring wall and the right upper inner ring wall; The at least two shielding shells further include a second left shielding shell and a second right shielding shell; the second left shielding shell and the second right shielding shell form a third annular structure surrounding the second annular structure; the second left shielding shell and the second right shielding shell are respectively used to surround the first left shielding shell and the first right shielding shell and have a second left annular opening close to the first left annular opening and a second right annular opening close to the first right annular opening; The second left shielding shell is separated from the first left shielding shell; and the second right shielding shell is separated from the first right shielding shell.

7. The current sensor according to claim 6, characterized in that: The shielding unit further includes a first left insulating shell and a first right insulating shell; the first left insulating shell and the first right insulating shell form a fourth annular structure; the first left first insulating shell and the first right insulating shell are respectively used to surround the first left shielding shell and the first right shielding shell and have a third left annular opening close to the left annular opening and a third right annular opening close to the first right annular opening; The second left shielding shell and the second right shielding shell are used to surround the first left insulating shell and the first right insulating shell respectively and have a second left annular opening close to the third left annular opening and a second right annular opening close to the third right annular opening.

8. The current sensor according to claim 5, characterized in that: The current path sensor further comprises an openable and closable unit, the openable and closable unit comprising a left shell, a right shell and an openable and closable structure respectively connected to the left shell and the right shell; the openable and closable structure is used to make the left shell and the right shell form a closed fifth annular structure; The left shell and the right shell respectively include a first elastic body and a second elastic body, which are used to reduce the gap between the left annular base and the right annular base in the fifth annular structure.

9. The current sensor according to claim 1, characterized in that: The material of the at least two shielding shells is soft magnetic material; Preferably, the soft magnetic material is Permalloy or nanocrystal.

10. A sensing device, characterized in that: The sensing device comprises a current sensor, and the current sensor is the current sensor according to any one of claims 1-9.

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