WO2023209967A1

WO2023209967A1 - Current sensor device, current sensor device array, and power converting device

Info

Publication number: WO2023209967A1
Application number: PCT/JP2022/019328
Authority: WO
Inventors: 開斗武島; 宗樹中田
Original assignee: 三菱電機株式会社
Priority date: 2022-04-28
Filing date: 2022-04-28
Publication date: 2023-11-02
Also published as: JPWO2023209967A1

Abstract

This current sensor device (100) comprises: a first magnetic shield (1) and a second magnetic shield (2) that are disposed so as to sandwich a busbar (30) that extends in a Y-axis direction and through which an electric current to be measured flows; and a magnetic sensor (3) that is disposed between the busbar (30) and the first magnetic shield (1). The first magnetic shield (1) includes a laminate (10) formed by stacking a first magnetic layer (11), a non-magnetic layer (12), and a second magnetic layer (13) in order in a Z-axis direction. The second magnetic layer (13) is closer to the magnetic sensor (3) than the first magnetic layer (11). Among the first magnetic layer (11) and the second magnetic layer (13), only the second magnetic layer (13) has a depletion portion (130) that is magnetically depleted.

Description

Current sensor device, current sensor device array, and power conversion device

The present disclosure relates to a current sensor device, a current sensor device array, and a power conversion device.

For example, an electric vehicle such as a hybrid vehicle (HV) includes a battery, a drive motor, and a power conversion device. The power converter converts DC power of a battery into AC power for driving a drive motor.

Japanese Unexamined Patent Application Publication No. 2019-109126 (Patent Document 1) describes a current sensor for measuring the current flowing between a power converter and a motor, including a bus bar serving as a current path, and a bus bar arranged in the thickness direction of the bus bar ( A first shield plate and a second shield plate are arranged to sandwich them from each other in the Z-axis direction (hereinafter referred to as the Z-axis direction) to absorb external magnetic fields, and a magnetic detection element is arranged between the first shield plate and the bus bar. A current sensor is disclosed.

In the current sensor described in Patent Document 1, the extending direction of the bus bar (hereinafter referred to as the Y-axis direction) is the same as the extending direction of each of the first magnetic shield plate and the second magnetic shield plate (hereinafter referred to as the X-axis direction). The magnetic sensor detects the magnetic field component in the X-axis direction of the magnetic field generated by the current flowing through the bus bar.

JP 2019-109126 Publication

However, in the above configuration, the generated magnetic field is concentrated on the magnetic shield. Therefore, between the magnetic shield where the magnetic sensor is placed and the bus bar, as it approaches the magnetic shield in the Z-axis direction, the direction of the magnetic flux points in the Z-axis direction, and the intensity of the magnetic field component that can be detected by the magnetic sensor increases. Attenuate. As a result, the current sensor having the above configuration has a low signal/noise ratio (hereinafter referred to as S/N ratio).

The main object of the present disclosure is to provide a current sensor device and a current sensor device array that have a higher S/N ratio than the above-described current sensor, and a power conversion device that includes at least one of the current sensor device and the current sensor device array. It is in.

A current sensor device according to the present disclosure includes a first magnetic shield and a second magnetic shield arranged to sandwich a bus bar extending in a first direction and through which a current to be measured flows, and a gap between the bus bar and the first magnetic shield. and a magnetic sensor located in the magnetic sensor. The first magnetic shield includes a laminate in which a first magnetic layer, a nonmagnetic layer, and a second magnetic layer are sequentially stacked in the second direction. The second magnetic layer is closer to the magnetic sensor than the first magnetic layer. Of the first magnetic layer and the second magnetic layer, only the second magnetic layer has a depletion portion that is magnetically depleted.

A current sensor device array according to the present disclosure includes a plurality of the above current sensor devices. The plurality of current sensor devices are arranged in a third direction perpendicular to each of the first direction and the second direction.

A power conversion device according to the present disclosure includes a main conversion circuit that converts and outputs input power, and a control circuit that controls the main conversion circuit. The control circuit includes at least one of the current sensor device and the current sensor device array, and controls the main conversion circuit based on the current value detected by the current sensor device or the current sensor device array.

According to the present disclosure, it is possible to provide a current sensor device and a current sensor device array that have a higher S/N ratio than the above-described current sensor, and a power conversion device that includes at least one of the current sensor device and the current sensor device array.

1 is a perspective view of a current sensor device according to Embodiment 1. FIG. FIG. 2 is a partial plan view of the current sensor device shown in FIG. 1; 2 is a sectional view taken along arrow III-III in FIG. 1. FIG. FIG. 3 is a perspective view of a current sensor device according to a second embodiment. FIG. 3 is a perspective view of a current sensor device according to a third embodiment. FIG. 7 is a perspective view of a current sensor device array according to a fourth embodiment. FIG. 7 is a perspective view showing a first modification of the current sensor device array according to the fourth embodiment. FIG. 7 is a perspective view showing a second modification of the current sensor device array according to the fourth embodiment. FIG. 3 is a block diagram of a power conversion device according to a fifth embodiment. FIG. 7 is a perspective view of a power conversion device according to a fifth embodiment.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the following drawings, the same or corresponding parts are given the same reference numerals and their descriptions will not be repeated. Further, for convenience of explanation, an X-axis direction (third direction), a Y-axis direction (first direction), and a Z-axis direction (second direction) that are orthogonal to each other are introduced. The dimensions shown in each drawing are examples optimized based on the configuration of the current sensor device according to each embodiment of the present disclosure. The dimensions of each part constituting the current sensor device according to the present disclosure are not limited to the dimensions shown in each figure, and can be arbitrarily set according to the configuration of the current sensor device according to each embodiment.

Hereinafter, the magnetic field generated by the current to be measured by the current sensor device will be simply referred to as a magnetic field, and the other magnetic fields will be referred to as external magnetic fields.

Embodiment 1.
<Configuration of current sensor device>
As shown in FIGS. 1 to 3, current sensor device 100 according to the first embodiment is for measuring the current flowing through bus bar 30 in the Y-axis direction. The current sensor device 100 includes a first magnetic shield 1, a second magnetic shield 2, and a magnetic sensor 3.

As shown in FIGS. 1 to 3, the first magnetic shield 1 and the second magnetic shield 2 are arranged to sandwich the bus bar 30 and the magnetic sensor 3 in the Z-axis direction. The first magnetic shield 1 and the second magnetic shield 2 are provided to absorb external magnetic fields. Bus bar 30 extends in the Y-axis direction. The magnetic sensor 3 is arranged between the bus bar 30 and the first magnetic shield 1 in the Z-axis direction.

As shown in FIG. 1, the first magnetic shield 1 includes a stacked body 10 in which a first magnetic layer 11, a nonmagnetic layer 12, and a second magnetic layer 13 are stacked in order in the Z-axis direction. The first magnetic layer 11 has the upper surface of the first magnetic shield 1 . The upper surface of the first magnetic shield 1 is a surface facing away from the bus bar 30 in the Z-axis direction. The second magnetic layer 13 has a lower surface of the first magnetic shield 1 . The lower surface of the first magnetic shield 1 is a surface facing the bus bar 30 side in the Z-axis direction.

The material constituting each of the first magnetic layer 11 and the second magnetic layer 13 may be any ferromagnetic material, but preferably a soft magnetic material. The material constituting each of the first magnetic layer 11 and the second magnetic layer 13 is, for example, selected from the group consisting of iron (Fe), nickel (Ni), cobalt (Co), permalloy (Ni-Fe alloy), and ferrite. Contains at least one of the selected items. The material constituting the non-magnetic layer 12 may be any non-magnetic material that does not exhibit ferromagnetism, and for example, at least one selected from the group consisting of aluminum (Al), copper (Cu), and epoxy resin. Including.

The nonmagnetic layer 12 has a surface joined to a surface of the first magnetic layer 11 located on the opposite side to the above-mentioned upper surface of the first magnetic shield 1, and a surface joined to the surface of the first magnetic layer 11 located on the opposite side to the above-mentioned lower surface of the first magnetic shield 1. It has a surface that is joined to the surface of the second magnetic layer 13. The above-mentioned joining may be realized by any joining method, for example, joining by high-pressure press working, or joining by adhesive or solder. For example, when the material constituting the nonmagnetic layer 12 is a nonmagnetic metal material such as aluminum (Al), the stacked body of the first magnetic layer 11, the nonmagnetic layer 12, and the second magnetic layer 13 is By pressing, each of the first magnetic layer 11 and the second magnetic layer 13 and the nonmagnetic layer 12 can be directly bonded (different materials bonded).

Note that, as described above, the joining method by press working is common in the manufacturing method of magnetic cores and magnetic shields.

As shown in FIG. 1, of the first magnetic layer 11 and the second magnetic layer 13 of the multilayer body 10, only the second magnetic layer 13 has a depletion portion 130 that is magnetically depleted and does not exhibit ferromagnetism. ing. The depletion portion 130 is filled with air, for example. Note that the depletion portion 130 may be filled with a material forming the nonmagnetic layer 12.

As shown in FIGS. 1 and 2, the second magnetic layer 13 has a first portion 131 and a second portion 132 that are arranged to sandwich a depletion portion 130 in the X-axis direction. The first portion 131 is, for example, separate from the second portion 132. The length of the depletion portion 130 in the Y-axis direction is, for example, equal to the length of the first magnetic layer 11 in the Y-axis direction. The length of the depletion portion 130 in the Z-axis direction is equal to the length (thickness) of the second magnetic layer 13 in the Z-axis direction. The length of the depletion portion 130 in the X-axis direction is shorter than the length of each of the first portion 131 and the second portion 132 in the X-axis direction.

Note that the first portion 131 may be partially connected to the second portion 132. The length of the depletion portion 130 in the Y-axis direction may be shorter than the length of the first magnetic layer 11 in the Y-axis direction. The second magnetic layer 13 may have an annular shape surrounding the entire periphery of the depletion portion 130 when viewed from the Z-axis direction.

As shown in FIG. 2, the length of the depletion portion 130 in the X-axis direction is shorter than the length of the bus bar 30 in the X-axis direction.

As shown in FIG. 2, the center line C1 connecting the centers of the depletion portion 130 in the X-axis direction is, for example, a straight line. When viewed from the Z-axis direction, the center line C1 overlaps with the center line of the first magnetic shield 1 in the X-axis direction.

As shown in FIG. 2, when viewed from the Z-axis direction, each of the first magnetic layer 11, nonmagnetic layer 12, and second magnetic layer 13 has

outer edge portions

11E, 12E, and 13E that overlap with each other. . In other words, the end faces of each of the first magnetic layer 11, the nonmagnetic layer 12, and the second magnetic layer 13 extending along the Z-axis direction are continuous so as to form the same plane. The lengths of the first magnetic layer 11, the nonmagnetic layer 12, and the second magnetic layer 13 in the X-axis direction are equal to each other. The length of the second magnetic layer 13 in the X-axis direction is the sum of the lengths of the first portion 131, the depletion portion 130, and the second portion 132 in the X-axis direction. The lengths of the first magnetic layer 11, the nonmagnetic layer 12, and the second magnetic layer 13 in the Y-axis direction are equal to each other.

As shown in FIG. 2, the length of each of the first magnetic layer 11, the nonmagnetic layer 12, and the second magnetic layer 13 in the X-axis direction is It is longer than the length of each of the magnetic layers 13 in the Y-axis direction. In other words, when viewed from the Z-axis direction, the first magnetic shield 1 has a longitudinal direction along the X-axis direction and a lateral direction along the Y-axis direction.

As shown in FIG. 2, the length of the second magnetic shield 2 in the X-axis direction is longer than the length of the second magnetic shield 2 in the Y-axis direction. In other words, when viewed from the Z-axis direction, the second magnetic shield 2 has a longitudinal direction along the X-axis direction and a lateral direction along the Y-axis direction. Preferably, the longitudinal direction of the second magnetic shield 2 is parallel to the longitudinal direction of the first magnetic shield 1.

As shown in FIG. 2, the outer edge of the second magnetic shield 2 overlaps with the outer edge 1E of the first magnetic shield 1, for example, when viewed from the Z-axis direction. The length of the second magnetic shield 2 in the X-axis direction is, for example, equal to the length of the first magnetic shield 1 in the X-axis direction. The length of the second magnetic shield 2 in the Y-axis direction is, for example, equal to the length of the first magnetic shield 1 in the Y-axis direction.

Preferably, the length of each of the first magnetic shield 1 and the second magnetic shield 2 in the X-axis direction is longer than the length (width) of the bus bar 30 in the X-axis direction.

The magnetic sensor 3 is provided to output a voltage output signal according to the strength (magnetic flux density) of the magnetic field component along the X-axis direction. The magnetic sensor 3 may have any configuration as long as it has the above configuration, and is, for example, a Hall element or a magnetoresistive (MR) element. The MR element uses, for example, an anisotropic magnetoresistive effect (AMR), a giant magnetoresistive effect (GMR), or a tunnel magnetoresistive effect (Tunnel magnetoresistive effect). Magnetic resistance such as Magneto Resistance Effect (TMR) This is an element that utilizes effects.

The magnetic sensor 3 has a magnetically sensitive portion 4. As seen from the Z-axis direction, as shown in FIG. 2, the magnetically sensitive portion 4 is arranged such that, for example, the entirety thereof overlaps a part of the depletion portion 130. Preferably, the magnetically sensitive portion 4 is arranged so as to overlap the center line C1 of the depletion portion 130 when viewed from the Z-axis direction. More preferably, the center line passing through the center of the magnetically sensitive portion 4 in the X-axis direction is arranged to overlap with the center line C1 of the depletion portion 130 when viewed from the Z-axis direction. Note that it is sufficient that at least a portion of the magnetically sensitive portion 4 is arranged so as to overlap at least a portion of the depletion portion 130.

As shown in FIG. 2, the length of the depletion portion 130 in the X-axis direction is equal to or longer than the length of the magnetically sensitive portion 4 of the magnetic sensor 3 in the X-axis direction. Preferably, the length of the depletion portion 130 in the X-axis direction is longer than, for example, the length of the magnetically sensitive portion 4 of the magnetic sensor 3 in the X-axis direction.

As shown in FIG. 2, the length of the depletion portion 130 in the Y-axis direction is equal to or longer than the length of the magnetically sensitive portion 4 of the magnetic sensor 3 in the Y-axis direction. Preferably, the length of the depletion portion 130 in the Y-axis direction is longer than the length of the magnetically sensitive portion 4 of the magnetic sensor 3 in the Y-axis direction.

As shown in FIG. 3, the center of the depletion portion 130 in the X-axis direction and the center of the magnetically sensitive portion 4 of the magnetic sensor 3 are arranged on a virtual straight line C2 extending along the Z-axis direction. The virtual straight line C2 is perpendicular to the center line C1.

As shown in FIG. 3, the bus bar 30 is arranged, for example, closer to the second magnetic shield 2 than at an intermediate position between the first magnetic shield 1 and the second magnetic shield 2 in the Z-axis direction. The distance between the bus bar 30 and the first magnetic shield 1 in the Z-axis direction is longer than the distance between the bus bar 30 and the second magnetic shield 2 in the Z-axis direction, for example. The material constituting the bus bar 30 may be any conductive material, and includes, for example, at least one of Al and Cu.

As shown in FIG. 3, the magnetic sensing portion 4 of the magnetic sensor 3 is spaced from each of the first magnetic shield 1 and the bus bar 30 in the Z-axis direction. As shown in FIG. 3, the distance in the Z-axis direction between the magnetically sensitive portion 4 of the magnetic sensor 3 and the first magnetic shield 1 is, for example, the distance in the Z-axis direction between the magnetically sensitive portion 4 of the magnetic sensor 3 and the bus bar 30. shorter than the axial distance. Preferably, the magnetically sensitive portion 4 of the magnetic sensor 3 is arranged at an intermediate position between the first magnetic shield 1 and the second magnetic shield 2 in the Z-axis direction. Note that the distance in the Z-axis direction between the magnetically sensitive portion 4 of the magnetic sensor 3 and the first magnetic shield 1 is equal to or equal to the distance in the Z-axis direction between the magnetically sensitive portion 4 of the magnetic sensor 3 and the bus bar 30. It may be longer. The magnetically sensitive portion 4 of the magnetic sensor 3 may be arranged closer to the first magnetic shield 1 than the intermediate position in the Z-axis direction. Further, the magnetically sensitive portion 4 of the magnetic sensor 3 may be arranged closer to the bus bar 30 than the intermediate position in the Z-axis direction.

<Method for manufacturing current sensor device>
An example of a method for manufacturing the current sensor device 100 will be described below. First, a first magnetic shield 1, a second magnetic shield 2, and a magnetic sensor 3 are prepared. The first magnetic shield 1 is constructed, for example, by forming an outer edge portion 1E on the laminate 10, and then removing a portion of the second magnetic layer 13 at a predetermined position with respect to the outer edge portion 1E to create a depletion portion 130. may be prepared by forming a. Second, the first magnetic shield 1 , the second magnetic shield 2 , and the magnetic sensor 3 are positioned with respect to the bus bar 30 . In this way, current sensor device 100 can be manufactured.

<Effects of current sensor device>
Below, the effects of the current sensor device 100 will be explained based on comparison with a comparative example. The current sensor described in Patent Document 1 is taken as a comparative example. In the comparative example, the direction of the magnetic flux generated between the magnetic shield and the bus bar is directed toward the Z-axis as it approaches the magnetic shield in the Z-axis direction. Therefore, as the position of the magnetic sensor in the Z-axis direction approaches the magnetic shield, the intensity of the magnetic field component in the X-axis direction that can be detected by the magnetic sensor is attenuated, and the S/N ratio becomes lower.

On the other hand, in the current sensor device 100, the first magnetic shield 1 includes a laminate in which the first magnetic layer 11, the nonmagnetic layer 12, and the second magnetic layer 13 are laminated in order in the Z-axis direction, and the second magnetic The layer 13 is closer to the magnetic sensor 3 than the first magnetic layer 11, and of the first magnetic layer 11 and the second magnetic layer 13, only the second magnetic layer 13 is magnetically depleted near the magnetic sensor. It has a depletion part. Therefore, the magnetic flux passing through the first portion 131 of the second magnetic layer 13 is caused by the difference in magnetic permeability between the magnetic material forming the first portion 131 and the non-magnetic material (air) forming the depletion portion 130. As a result, the magnetism leaks into the depletion portion 130 and is again concentrated in the second portion 132 of the second magnetic layer 13 . Therefore, in the current sensor device 100, the magnetic flux passing through the inside of the depletion part 130 and the region close to the depletion part 130 in the Z-axis direction is directed in the X-axis direction, so that the magnetic flux penetrating the magnetically sensitive part 4 of the magnetic sensor 3 is The magnetic flux passing between the first magnetic shield 1 and the bus bar 30 and the magnetic flux passing through each of the first portion 131 and the second portion 132 of the second magnetic layer 13 of the first magnetic shield 1 are superimposed. Become. As a result, in the current sensor device 100, the magnetic flux passing through the first portion 131, the depletion portion 130, and the second portion 132 of the second magnetic layer 13 compensates for the attenuation of the intensity of the magnetic field component in the X-axis direction. Ru. In other words, the intensity change of the magnetic field component in the X-axis direction between the first magnetic shield 1 and the bus bar 30 of the current sensor device 100 becomes gentler than in the comparative example. The S/N ratio of such current sensor device 100 is higher than that of a conventional current sensor. In addition, in such a current sensor device 100, even if the relative position of the magnetic sensor 3 in the Z-axis direction with respect to the first magnetic shield 1, the second magnetic shield 2, and the bus bar 30 changes due to manufacturing errors, the S/N The ratio is not easily affected by the amount of variation in the relative position. In other words, the robustness of the current sensor device 100 is higher than that of conventional current sensors.

Furthermore, in the current sensor device 100, since the first magnetic shield 1 includes a laminate in which the first magnetic layer 11, the nonmagnetic layer 12, and the second magnetic layer 13 are laminated in order in the Z-axis direction, the second magnetic layer 13 The first magnetic layer 11, which is magnetically separated from the first magnetic layer 11, can absorb an external magnetic field. Therefore, the S/N ratio of the current sensor device 100 is higher than that of a current sensor device including the first magnetic shield made of only the second magnetic layer 13.

In the current sensor device 100, since the depletion portion 130 is arranged so as to overlap the magnetically sensitive portion 4 of the magnetic sensor 3 when viewed from the Z-axis direction, the depletion portion 130 is arranged so as not to overlap the magnetically sensitive portion 4 of the magnetic sensor 3. The attenuation of the strength of the magnetic field component in the X-axis direction can be compensated for more effectively than when the magnetic field component is disposed in the X-axis direction. Therefore, the S/N ratio of the current sensor device 100 is higher than that of a current sensor device in which the depletion portion 130 is arranged so as not to overlap the magnetic sensing portion of the magnetic sensor 3.

In particular, in the current sensor device 100, in a cross section orthogonal to the Y-axis direction, the center of the depletion portion 130 in the X-axis direction and the center of the magnetically sensitive portion 4 in the 3), so the magnetic field component in the X-axis direction is The intensity attenuation can be compensated more effectively. Therefore, the S/N ratio of the current sensor device 100 is higher than that of a current sensor device in which the depletion portion 130 is arranged so as not to overlap the magnetic sensing portion of the magnetic sensor 3.

In the current sensor device 100, the length (width) of the depletion portion 130 is longer than the length (width) of the magnetically sensitive portion 4 in the X-axis direction. Even if the relative position of the magnetically sensitive part 4 in the X-axis direction with respect to the depletion part 130 changes due to manufacturing errors, the S/N ratio will change due to the change in the relative position compared to the case where it is the same or shorter. Less affected by quantity.

In the current sensor device 100, when viewed from the Z-axis direction, each of the first magnetic layer 11, the nonmagnetic layer 12, and the second magnetic layer 13 has

outer edge portions

11E, 12E, and 13E (outer edge portion 1E) that overlap with each other. ing. Such

outer edge portions

11E, 12E, and 13E may be formed at the same time by processing the laminate 10. Further, depletion portions 130 may be formed at predetermined positions relative to

outer edges

11E, 12E, and 13E. Therefore, in the current sensor device 100, the relative position of the depletion portion 130 with respect to the

outer edge portions

11E, 12E, and 13E is unlikely to change due to manufacturing errors or the like.

Embodiment 2.
As shown in FIG. 4, the current sensor device 101 according to the second embodiment has basically the same configuration as the current sensor device 100 according to the first embodiment, and has the same effects, but the second magnetic shield The current sensor device 2 is different from the current sensor device 100 in that the current sensor device 2 has a pair of opposing portions 22 that are arranged to face each other with a bus bar 30 in between in the X-axis direction. Below, the differences between current sensor device 101 and current sensor device 100 will be mainly explained.

As shown in FIG. 4, the second magnetic shield 2 is disposed on the opposite side of the first magnetic shield 1 in the Z-axis direction with respect to the bus bar 30, and has an extension portion 21 extending along the X-axis direction. It further has. The extending portion 21 is provided, for example, so as to overlap the first magnetic shield 1 when viewed from the Z-axis direction. One end and the other end of the extending portion 21 in the X-axis direction are arranged outside the bus bar 30 in the X-axis direction. One of the pair of opposing portions 22 protrudes from one end of the extending portion 21 in the X-axis direction toward the first magnetic shield 1 side in the Z-axis direction. The other of the pair of opposing portions 22 protrudes from the other end of the extension portion 21 in the X-axis direction toward the first magnetic shield 1 side in the Z-axis direction.

From a different perspective, the second magnetic shield 2 is provided so as to surround the bus bar 30 on three sides when viewed from the Y-axis direction. The outer shape of the second magnetic shield 2 is approximately U-shaped when viewed from the Y-axis direction.

The length of each of the pair of opposing portions 22 in the X-axis direction is shorter than the length of each of the first portion 131 and second portion 132 of the second magnetic layer 13 in the X-axis direction. Each end portion (hereinafter referred to as an upper end portion) of the pair of opposing portions 22 located on the first magnetic shield 1 side in the Z-axis direction is connected to each of the first portion 131 and the second portion 132 of the second magnetic layer 13. It is arranged so as to overlap in the Z-axis direction with a portion located outside of the center in the X-axis direction.

The length of the pair of opposing portions 22 in the Y-axis direction is, for example, equal to the length of the extending portion 21 in the Y-axis direction.

As shown in FIG. 4, each of the pair of opposing portions 22 protrudes toward the first magnetic shield 1 side relative to the bus bar 30 in the Z-axis direction, for example. The upper end portions of each of the pair of opposing portions 22 are arranged to sandwich the magnetic sensor 3, for example, in the X-axis direction.

In the current sensor device 101, among the magnetic fields generated by the current flowing through the bus bar 30, the magnetic flux passing through the second magnetic shield 2 side with respect to the bus bar 30 also passes through the pair of opposing portions 22, and passes through the first magnetic shield 2 side with respect to the bus bar 30. Guided to the 1st side. Therefore, the magnetic flux penetrating the magnetically sensitive portion of the magnetic sensor 3 of the current sensor device 101 is guided toward the first magnetic shield 1 side with respect to the bus bar 30 by the pair of opposing portions 22, in addition to what has been explained regarding the current sensor device 100. Includes magnetic flux. When the current value flowing through each bus bar 30 of the current sensor device 101 and the current sensor device 100 is the same, the strength of the magnetic field component along the X-axis direction between the first magnetic shield 1 of the current sensor device 101 and the bus bar 30 is larger than the intensity of the magnetic field component along the X-axis direction between the first magnetic shield 1 and the bus bar 30 of the current sensor device 101, and the magnetic flux that penetrates the magnetically sensitive portion of the magnetic sensor 3 of the current sensor device 101 is The density becomes higher than the magnetic flux density that penetrates the magnetically sensitive portion of the magnetic sensor 3 of the current sensor device 100. As a result, the S/N ratio of current sensor device 101 can be further increased than that of current sensor device 100.

Embodiment 3.
As shown in FIG. 5, the current sensor device 102 according to the third embodiment has basically the same configuration as the current sensor device 100 according to the first embodiment, and has the same effect, but the first magnetic shield The current sensor device 100 differs from the current sensor device 100 in that it further includes a substrate 5 disposed between the magnetic sensor 1 and the magnetic sensor 3. Below, the differences between the current sensor device 102 and the current sensor device 100 will be mainly explained.

The substrate 5 has a first surface 5A on which the first magnetic shield 1 is mounted, and a second surface 5B located on the opposite side of the first surface 5A and on which the magnetic sensor 3 is mounted. The method of mounting each of the first magnetic shield 1 and the magnetic sensor 3 is not particularly limited. Each of the first magnetic shield 1 and the magnetic sensor 3 may be mounted on the substrate 5 using an adhesive or solder, or may be fitted into a through hole or a recess formed in the substrate 5 in advance. Good too.

The material constituting the substrate 5 may be any non-magnetic material, including, for example, epoxy resin.

In the method for manufacturing the current sensor device 102, the first magnetic shield 1 and the magnetic sensor 3 can be prepared as being mounted on the substrate 5, so it is assumed that the first magnetic shield 1 and the magnetic sensor 3 are separate members independent of each other. Compared to the case where the depletion portion 130 of the first magnetic shield 1 and the magnetically sensitive portion 4 of the magnetic sensor 3 are prepared and positioned as such, fluctuations in the relative positions of the depletion portion 130 of the first magnetic shield 1 and the magnetic sensing portion 4 of the magnetic sensor 3 can be suppressed.

On each of the first surface 5A and second surface 5B of the substrate 5, for example, a mounting area for the first magnetic shield 1 or the magnetic sensor 3 is printed by silk printing or the like, or a counterbore is formed in the mounting area. It's okay. In this way, displacement in the relative positions of the first magnetic shield 1 and the magnetic sensor 3 can be suppressed. In particular, in the current sensor device 101 as well, the attenuation of the strength of the magnetic field component in the X-axis direction can be compensated for as described above, but the degree of this effect depends on the relative position between the magnetic sensor 3 and the first magnetic shield 1. Increase or decrease depending on If the relative positional deviation between the first magnetic shield 1 and the magnetic sensor 3 is suppressed, variations in the above effects can be suppressed.

Note that the current sensor device according to the third embodiment may have the same configuration as the current sensor device 101 according to the second embodiment, except for including the substrate 5.

Embodiment 4.
The current sensor device array according to the fourth embodiment includes a plurality of current sensor devices according to the first embodiment. In the current sensor device array according to the fourth embodiment, each current sensor device is the current sensor device 100 according to the first embodiment, the current sensor device 101 according to the second embodiment, or the current sensor device according to the third embodiment. It has the same configuration as 102. In the current sensor device array according to the fourth embodiment, each current sensor device is provided to measure, for example, one alternating current in a multiphase alternating current.

The current sensor device array 110 shown in FIG. 6 includes three

current sensor devices

100a, 100b, and 100c. Each

current sensor device

100a, 100b, 100c is provided to measure, for example, one phase of three-phase alternating current. Single-phase alternating current flows through each of the bus bar 30a of the current sensor device 100a, the bus bar 30b of the current sensor device 100b, and the bus bar 30c of the current sensor device 100c. The magnetic sensor 3a of the current sensor device 100a detects the magnetic field generated by the single-phase alternating current flowing through the bus bar 30a, and the magnetic sensor 3b of the current sensor device 100b detects the magnetic field generated by the single-phase alternating current flowing through the bus bar 30b. The sensors 3c each detect the magnetic field generated by the single-phase alternating current flowing through the bus bar 30c. The

current sensor devices

100a, 100b, and 100c are arranged, for example, in line in the X-axis direction. Note that the direction in which the

current sensor devices

100a, 100b, and 100c are arranged is not particularly limited, and may be along the Z-axis direction, for example.

In the current sensor device array 110, each of the

current sensor devices

100a, 100b, and 100c has the same configuration as the current sensor device 100 according to the first embodiment. Each

current sensor device

100a, 100b, 100c includes a first magnetic shield 1 having a depletion portion 130. Therefore, the current sensor device array 110 provides the same effects as the current sensor device 100.

The current sensor device array according to the fourth embodiment can be modified as follows.
In the current sensor device array according to the fourth embodiment, each current sensor device may be provided to measure single-layer alternating current flowing independently of each other.

As shown in FIG. 7, in the current sensor device array according to the fourth embodiment, at least one of the first magnetic shield 1 and the second magnetic shield 2 of each current sensor device is configured as the same member. Good too. In this case, each current sensor device in the current sensor device array is arranged side by side in the X-axis direction.

In the current sensor device array 111 shown in FIG. 7, the first magnetic shield 1 has a plurality of

depletion portions

130a, 130b, and 130c formed at intervals in the X-axis direction. Furthermore, the first magnetic shield 1 has a third portion 131a, a fourth portion 134, a fifth portion 135, and a sixth portion 132c.

The third portion 131a, the depletion portion 130a, and the fourth portion 134 have the same configuration as the first portion 131, the depletion portion 130, and the second portion 132 in the current sensor device 100. The relationship between each of the third portion 131a and the fourth portion 134 and the depletion portion 130a is equivalent to the relationship between each of the first portion 131 and the second portion 132 and the depletion portion 130 in the current sensor device 100.

The fourth portion 134, the depletion portion 130b, and the fifth portion 135 have the same configuration as the first portion 131, the depletion portion 130, and the second portion 132 in the current sensor device 100. The relationship between each of the fourth portion 134 and the fifth portion 135 and the depletion portion 130b is equivalent to the relationship between each of the first portion 131 and the second portion 132 and the depletion portion 130 in the current sensor device 100. From a different perspective, the fourth portion 134 corresponds to a member in which the second portion 132a for the depletion portion 130a and the first portion 131b for the depletion portion 130b shown in FIG. 6 are integrated.

The fifth portion 135, the depletion portion 130c, and the sixth portion 132c have the same configuration as the first portion 131, the depletion portion 130, and the second portion 132 in the current sensor device 100. That is, the relationship between each of the fifth portion 135 and the sixth portion 132c and the depletion portion 130c is equivalent to the relationship between each of the first portion 131 and the second portion 132 and the depletion portion 130 in the current sensor device 100. From a different perspective, the fifth portion 135 corresponds to a member in which the second portion 132b for the depletion portion 130c and the first portion 131c for the depletion portion 130c shown in FIG. 6 are integrated.

Since the current sensor device array 111 shown in FIG. 7 includes one each of the first magnetic shield 1 and the second magnetic shield 2, the current sensor device array 111 shown in FIG. Compared to the sensor device array 110, the number of parts and manufacturing steps can be reduced.

As shown in FIG. 8, each current sensor device of the current sensor device array according to the fourth embodiment has the same configuration as the current sensor device 102 according to the third embodiment, and each

current sensor device

102a , 102b, 102c may be configured as the same member.

Since the current sensor device array 112 shown in FIG. 8 includes one substrate 5, the number of parts and manufacturing steps can be reduced compared to a current sensor device array including a plurality of substrates 5.

Furthermore, in the current sensor device array 112 shown in FIG. are mounted and positioned, it is possible to suppress relative displacement of each of the plurality of

current sensor devices

102a, 102b, and 102c.

In the current sensor device array 112 as well, the mounting area of each first magnetic shield 1 or magnetic sensor 3 may be printed on each of the first surface 5A and the second surface 5B of the substrate 5, or the mounting area may be printed on each of the first magnetic shield 1 or the magnetic sensor 3. A counterbore may be formed. In this way, the relative positional deviation between each first magnetic shield 1 and each magnetic sensor 3 can be suppressed. In particular, in the current sensor device 101 as well, the attenuation of the strength of the magnetic field component in the X-axis direction can be compensated for as described above, but the degree of this effect depends on the relative position between the magnetic sensor 3 and the first magnetic shield 1. Increase or decrease depending on If the relative positional deviation between the first magnetic shield 1 and the magnetic sensor 3 is suppressed, variations in the above effects can be suppressed.

Embodiment 5.
A power conversion device 200 according to the fifth embodiment is a power conversion device in which at least one of the current sensor devices according to the first to third embodiments and the current sensor device array according to the fourth embodiment is applied. Power conversion device 200 according to Embodiment 5 includes a main conversion circuit that converts and outputs input power, and a control circuit that controls the main conversion circuit. The control circuit controls the main conversion circuit based on the current value detected by the current sensor device according to the first to third embodiments or the current sensor device array according to the fourth embodiment.

Although the present disclosure is not limited to a specific power conversion device, a case will be described below as Embodiment 5 in which the present disclosure is applied to a three-phase inverter.

FIG. 9 is a block diagram showing the configuration of a power conversion system to which the power conversion device according to Embodiment 5 is applied.

The power conversion system shown in FIG. 9 is composed of a power source 300, a power conversion device 200, and a load 400. Power supply 300 is a DC power supply and supplies DC power to power conversion device 200. The power source 300 can be composed of various things, for example, it can be composed of a DC system, a solar battery, a storage battery, or it can be composed of a rectifier circuit or an AC/DC converter connected to an AC system. Good too. Moreover, the power supply 300 may be configured with a DC/DC converter that converts DC power output from a DC system into predetermined power.

The power conversion device 200 is a three-phase inverter connected between a power source 300 and a load 400, converts DC power supplied from the power source 300 into AC power, and supplies AC power to the load 400. As shown in FIG. 9, the power conversion device 200 includes a main conversion circuit 201 that converts DC power into AC power and outputs it, and a control circuit that outputs a control signal for controlling the main conversion circuit 201 to the main conversion circuit 201. 202. The main conversion circuit 201 includes a bus bar 30a, a bus bar 30b, and a bus bar 30c. Currents of each phase flow in the Y-axis direction through each of the

bus bars

30a, 30b, and 30c.

The load 400 is a three-phase electric motor driven by AC power supplied from the power converter 200. Note that the load 400 is not limited to a specific application, but is a motor installed in various electrical devices, and is used, for example, as a motor for a hybrid vehicle, an electric vehicle, a railway vehicle, an elevator, or an air conditioner.

Power conversion device 200 includes at least one of the current sensor devices according to Embodiments 1 to 3 and the current sensor device array according to

Embodiments

4 and 5, which have a higher S/N ratio than conventional current sensor devices. Therefore, the control circuit can control the main conversion circuit based on highly accurate measurement results obtained by the current sensor device. As a result, the conversion accuracy of power conversion device 200 is higher than that of a power conversion device including a conventional current sensor device.

The power conversion device 200 shown in FIG. 10 includes the current sensor device array 112 shown in FIG. 8. On the substrate 5, active elements and passive elements constituting a control circuit are mounted. In such a power conversion device 200, the current sensor device array 112 is formed integrally with the control circuit, so it can be made smaller compared to a case where the current sensor array is formed separately from the control circuit.

Embodiments 1-5 disclosed this time should be considered to be illustrative in all respects and not restrictive. Unless there is a contradiction, at least two of the embodiments 1 to 5 disclosed herein may be combined. The scope of the present disclosure is indicated by the claims rather than the above description, and is intended to include meanings equivalent to the claims and all changes within the range.

1 First magnetic shield, 1E, 11E, 12E, 13E outer edge, 2 Second magnetic shield, 3, 3a, 3b, 3c magnetic sensor, 4 Magnetically sensitive part, 5 Substrate, 5A first surface, 5B second surface, 10 Laminated body, 11 First magnetic layer, 12 Non-magnetic layer, 13 Second magnetic layer, 21 Extending portion, 22 Opposing portion, 30, 30a, 30b, 30c Bus bar, 100, 100a, 100b, 100c, 101, 102 , 102B, 102C, 102a, 102b, 102c Current sensor device, 110, 111, 112 Current sensor device array, 130, 130a, 130b, 130c Depletion part, 131, 131b, 131c First part, 131a Third part, 132, 132a, 132b second part, 132c sixth part, 134 fourth part, 135 fifth part, 200 power conversion device, 201 main conversion circuit, 202 control circuit, 300 power supply, 400 load.

Claims

a first magnetic shield and a second magnetic shield arranged in a second direction orthogonal to the first direction so as to sandwich a bus bar extending in the first direction and through which a current to be measured flows;
a magnetic sensor disposed between the bus bar and the first magnetic shield,
The first magnetic shield includes a laminate in which a first magnetic layer, a nonmagnetic layer, and a second magnetic layer are laminated in order in the second direction,
the second magnetic layer is closer to the magnetic sensor than the first magnetic layer;
A current sensor device, wherein of the first magnetic layer and the second magnetic layer, only the second magnetic layer has a depletion portion that is magnetically depleted.
The magnetic sensor has a magnetically sensitive portion,
The current sensor device according to claim 1, wherein the depletion portion is arranged to overlap the magnetically sensitive portion when viewed from the second direction.
In a cross section perpendicular to the first direction, the center of the depletion part in a third direction perpendicular to each of the first direction and the second direction, and the center of the magnetically sensitive part in the third direction are The current sensor device according to claim 2, wherein the current sensor device is arranged on a virtual straight line extending in two directions.
The current sensor device according to claim 2 or 3, wherein the length of the depletion portion is longer than the length of the magnetically sensitive portion in a third direction perpendicular to each of the first direction and the second direction.
5. The method according to claim 1, wherein each of the first magnetic layer, the non-magnetic layer, and the second magnetic layer has outer edge portions that overlap with each other when viewed from the second direction. Current sensor device as described.
Claims 1 to 5, wherein the second magnetic shield has a pair of opposing portions that are arranged opposite to each other across the bus bar in a third direction perpendicular to each of the first direction and the second direction. The current sensor device according to any one of the above.
A plurality of current sensor devices according to any one of claims 1 to 6 are provided,
The plurality of current sensor devices are a current sensor device array arranged in a third direction orthogonal to each of the first direction and the second direction.
The current sensor device array according to claim 7, wherein the first magnetic shields of each of the plurality of current sensor devices are provided integrally with each other.
further comprising a substrate disposed between the first magnetic shield and the magnetic sensor of each of the plurality of current sensor devices,
The substrate is located on a first surface on which the first magnetic shield of each of the plurality of current sensor devices is mounted, and is located on a side opposite to the first surface and has a first surface on which the first magnetic shield of each of the plurality of current sensor devices is mounted. The current sensor device array according to claim 7 or 8, further comprising a second surface on which a magnetic sensor is mounted.
a main conversion circuit that converts input power and outputs it;
and a control circuit that controls the main conversion circuit,
The main conversion circuit includes the bus bar,
The control circuit includes at least one of the current sensor device according to any one of claims 1 to 6 and the current sensor device array according to any one of claims 7 to 9, and the current sensor device Alternatively, a power conversion device that controls the main conversion circuit based on a current value flowing through the bus bar detected by the current sensor device array.
a main conversion circuit that converts input power and outputs it;
and a control circuit that controls the main conversion circuit,
The main conversion circuit includes the bus bar,
The control circuit includes a current sensor device array according to claim 9, and controls the main conversion circuit based on a current value flowing through the bus bar detected by the current sensor device or the current sensor device array. ,
A power conversion device, wherein the control circuit is mounted on the board.