JP5630633B2 - Multiphase current detector - Google Patents

Description

  In the present invention, a polyphase is formed by a plurality of primary conductors having a counterbore or U-shaped portion to which a current to be measured is applied, and is applied to each phase in the vicinity of each counterbore or U-shaped portion. The present invention relates to a multiphase current detection device for detecting a measured current.

  Conventionally, as a method for measuring a current to be measured in a non-contact manner, there is generally a method using a magnetic core. In a current sensor using a magnetic core, the magnetic core is installed so as to surround a conductor through which a current to be measured flows, and a magnetic circuit is formed together with a gap portion provided in the magnetic core. The magnitude of the current to be measured is measured in a non-contact manner by measuring the magnitude of the magnetic flux generated in the magnetic circuit by the current to be measured through the magnetoelectric conversion element installed in the gap portion.

  In recent years, a coreless type current sensor that does not use a magnetic core has been proposed for the purpose of miniaturization, weight reduction, high accuracy, and the like, particularly in large current measurement. As a multiphase current detection device using a coreless type current sensor, each surface mount type current sensor is arranged in the center of each detected current path bent at a right angle in a crank shape twice, and each detected current path is Some are aligned (see, for example, Patent Document 1).

  As another multiphase current detection device, each magnetoelectric conversion element is arranged in the vicinity of a bent portion of each conductor to be measured having a bent portion bent in a crank shape so that the bent portions do not overlap each other. There is one in which measurement conductors are arranged substantially in parallel (see, for example, FIG. 6 of Patent Document 2).

  JP-A-2005-233692   JP 2001-74783 A

Problems to be solved by the invention

  In the multiphase current detection device disclosed in Patent Document 1, when a multiphase current is measured by using a surface mount type current sensor, the surface mount type current sensor for detecting a current of a certain phase is different from the other phase. The multi-phase current can be detected without being basically affected by the magnetic field generated by the current. However, strictly speaking, since the leakage magnetic field from the detected current path of the other phase is applied in the direction of magnetic sensing of the surface mount type current sensor, it is detected when each phase is close and installed in a small space-saving manner. There was a problem that an error occurred and it was not suitable for miniaturization.

  Moreover, in the said patent document 2, the magnetoelectric conversion element whose magnetosensitive direction is an out-of-plane direction is each arrange | positioned in the vicinity of the bending part of each to-be-measured conductor which has the bending part bent in crank shape, and a bending part overlaps. Since the conductors to be measured are arranged substantially parallel to each other, the multiphase current can be detected without being affected by the magnetic field generated by the current of the other phase. However, since it is necessary to dispose the bent portions so that the bent portions do not overlap with each other, there is a problem that the current detector increases in size accordingly. Further, when each magnetoelectric conversion element is installed on the same substrate, there is a problem that not only the current detector but also the substrate is increased in size and is not suitable for cost reduction.

  The present invention has been made in order to solve the problems as described above, reduces the influence of other phase currents when detecting a multiphase current, can detect a more accurate current in each phase, and has a magnetic sensing direction. An object of the present invention is to obtain a multi-phase current detection device that is small in size and low in cost even when using a magnetoelectric conversion element having an out-of-plane direction.

Means for solving the problem

  The multiphase current detection device according to the present invention includes a plurality of primary conductors each having at least one counterbore portion, and an inner surface of at least one counterbore portion of each primary conductor in a direction outside the surface of the magnetosensitive surface. At least one magnetoelectric conversion element installed so that a magnetic flux generated by the measurement current is applied, and the center position of the cross section of the primary conductor different from the counterbore part substantially coincides with the magnetosensitive surface of the magnetoelectric conversion element In addition, the plurality of primary conductors are substantially parallel to each other and arranged in the same plane.

  According to another aspect of the present invention, there is provided a multiphase current detection device including a plurality of primary conductors each having at least one U-shaped portion, and a magnetosensitive surface within at least one U-shaped portion of each primary conductor. And at least one magnetoelectric conversion element installed so that a magnetic flux generated by the current to be measured is applied in the out-of-plane direction, and the central position of the cross section of the primary conductor different from the U-shaped portion and the magnetoelectric conversion element These magnetic sensitive surfaces substantially coincide with each other, and the plurality of primary conductors are substantially parallel to each other and arranged in the same plane.

  According to another aspect of the present invention, there is provided a multiphase current detection device including a plurality of primary conductors each having at least one U-shaped portion, and a magnetosensitive surface within at least one U-shaped portion of each primary conductor. At least one magnetoelectric conversion element installed so that a magnetic flux generated by the current to be measured is applied in the out-of-plane direction, and the position of the center of gravity of the cross section of the U-shaped portion and the magnetosensitive surface of the magnetoelectric conversion element are substantially The plurality of primary conductors are substantially parallel to each other and arranged in the same plane.

  In the multiphase current detection device according to the present invention, each magnetoelectric conversion element is installed on at least one sensor board, and the sensor board places the magnetoelectric conversion element at a predetermined position in the counterbore part or the U-shaped formation part. It is held and fixed on the primary conductor.

  According to another aspect of the present invention, there is provided a multiphase current detection device in which a conductive shield layer is provided inside a sensor substrate, and a sensor circuit portion is provided on the surface of the sensor substrate.

Effect of the invention

As described above, according to the present invention, since the magnetoelectric conversion element whose magnetic sensing direction is the out-of-plane direction is installed in each counterbore part of each primary conductor, each counterbore part in the longitudinal direction of each primary conductor. Even if they are installed overlapping each other, there is an effect of reducing the influence of the magnetic field generated by the current of the other phase when detecting the multiphase current and detecting the current to be measured with high accuracy.
Further, the counterbore portions may overlap each other as described above, and it is not necessary to displace the counterbore portions, so that the size of the multiphase current detection device does not increase in the longitudinal direction of the primary conductor, and the size is small. Has the effect of

In addition, since the magnetoelectric transducers having the magnetosensitive direction in the out-of-plane direction are installed in the respective U-shaped forming portions of the respective primary conductors, the respective U-shaped forming portions overlap each other in the longitudinal direction of the respective primary conductors. Even when installed, there is an effect of reducing the influence of the magnetic field generated by the current of the other phase when detecting the multiphase current and detecting the current to be measured with high accuracy.
Further, as described above, the U-shaped forming portions may overlap each other, and it is not necessary to shift the U-shaped forming portions so that the dimensions of the multiphase current detecting device are increased in the longitudinal direction of the primary conductor. There is no effect of downsizing.

  In addition, at least one small sensor substrate can cope with multiple phases, and the apparatus can be miniaturized, thereby simplifying the manufacturing process and reducing costs.

  Furthermore, by providing a shield layer on the inner layer of the sensor substrate, electric field noise mainly generated from the primary conductor can be removed or reduced with respect to the sensor circuit unit, which has the effect of increasing the accuracy of the sensor output. .

It is a perspective view of the primary conductor of the detection apparatus of the multiphase current by Embodiment 1 of this invention. It is a top view of the detection apparatus of the multiphase current by Embodiment 1 of this invention. It is sectional drawing of the detection apparatus of the multiphase current by Embodiment 1 of this invention. It is a magnetic flux diagram of the counterbore part cross-section vicinity in one current sensor by Embodiment 1 of this invention. It is magnetic flux vector explanatory drawing of the magnetic sensing part vicinity in the magnetoelectric conversion element of one current sensor by Embodiment 1 of this invention. It is magnetic flux vector explanatory drawing of the magnetic sensing part vicinity in another magnetoelectric conversion element of one current sensor by Embodiment 1 of this invention. It is a perspective view of the primary conductor of the detection apparatus of the multiphase current by Embodiment 2 of this invention. It is a top view of the detection apparatus of the multiphase current by Embodiment 2 of this invention. It is sectional drawing of the detection apparatus of the multiphase current by Embodiment 2 of this invention. It is a magnetic flux diagram of the U-shaped formation part cross section vicinity in one current sensor by Embodiment 2 of this invention. It is a perspective view of another primary conductor of the detection apparatus of the multiphase current by Embodiment 2 of this invention. It is a perspective view of the detection apparatus of the multiphase current by Embodiment 3 of this invention. It is a top view of the detection apparatus of the multiphase current by Embodiment 3 of this invention. It is sectional drawing of the detection apparatus of the multiphase current by Embodiment 3 of this invention.

Embodiment 1 FIG.
FIG. 1 shows a perspective view of only a primary conductor 4 in a multiphase current detection apparatus 1 according to Embodiment 1 of the present invention. FIG. 2 is a plan view (XY plane) of the multiphase current detection apparatus 1. 3 is a cross-sectional view showing the AA cross section (YZ plane) in FIGS. 1 and 2, and FIG. 4 is a magnetic flux diagram at the time of applying the current to be measured in the AA cross section (YZ plane) for one phase in FIGS. is there. The multiphase current detection device 1 shown in the figure is an example in which, for example, in a three-phase alternating current, each phase current is detected by a current sensor 2 installed for each phase. It is composed of a magnetoelectric conversion element 3 and a primary conductor 4, and the primary conductor 4 is further provided with a counterbore part 5. In the figure, the primary conductor 4 is shown only in the vicinity of the current sensor 2 for simplicity, but it is actually extended and connected to a power source, various devices, and the like. In the actual apparatus configuration, the magnetoelectric conversion element 3 is installed connected to a printed circuit board or the like, but is omitted here and will be described in another embodiment.
In the first embodiment, counterbore portions 5 are formed in a part of each primary conductor 4, one magnetoelectric conversion element 3 is arranged in each counterbore portion 5, and each counterbore portion 5 is the longitudinal length of each primary conductor 4. The primary conductors 4 are arranged substantially in parallel so as to overlap with the direction.

First, the overall configuration of the multiphase current detection device 1 and the configuration of the current sensor 2 will be described.
As shown in FIG. 1, each primary conductor 4 to which a current to be measured is applied is a linear conductor, and here is a detection example of a three-phase current, and therefore three primary conductors are arranged substantially in parallel. . Each primary conductor 4 is provided with a current sensor 2, and is configured such that each current sensor 2 detects a measured current value of each phase. Each current sensor 2 is installed at a position overlapping each other in the longitudinal direction of each primary conductor 4, that is, in the X direction.
The configuration of the current sensor 2 for one phase will be described first from the primary conductor 4. A part of the upper surface of each primary conductor 4 is subjected to counterbore processing, and the counterbored depth in the Z direction is formed to be at least half of the height in the Z direction of the primary conductor 4 which is a non-counterbore part. . The cross-sectional area occupied by the primary conductor in the vicinity of the counterbore part 5 of the primary conductor 4 depends on the type of the magnetoelectric conversion element to be used, but is approximately within the range of the magnetic flux density desired to be applied to the magnetoelectric conversion element 3, that is, the current to be measured to be detected. Will be decided accordingly. If a large current value is detected, it is desirable that the cross-sectional area is large in order to reduce the current density of the primary conductor portion in the vicinity of the counterbore part 5, and if a small current value is detected, the primary conductor in the vicinity of the counterbore part 5 In order to increase the current density of the portion, it is desirable that the cross-sectional area is small. Further, as is apparent from the plan view of FIG. 2, the counterbore portions 5 are installed so that the positions of the counterbore portions 5 overlap in the longitudinal direction of the primary conductor 4, that is, the X direction here. Such a primary conductor 4 is produced by cutting a rectangular parallelepiped primary conductor 4 from, for example, a metal plate material such as copper, and then forming a counterbored portion by counterboring, or by casting or the like.
At least one magnetoelectric conversion element 3 is installed in each counterbore part 5 and constitutes the current sensor 2 together with the primary conductor 4. When a current to be measured is applied to the primary conductor 4, a magnetic flux is generated around the primary conductor 4. Here, the surface of the magnetosensitive surface 8 provided inside the magnetoelectric conversion element 3 with the magnetic flux in the Y direction. An element having a magnetosensitive direction in an out-of-plane direction that is measured outside is used. For example, as the above-described element, a Hall element or a Hall IC in which a Hall element and a processing circuit are integrated is used, but the element is not limited thereto. The position where the magnetoelectric conversion element 3 is installed will be described with reference to FIG. 3. The magnetosensitive surface 8 of each magnetoelectric conversion element 3 substantially coincides with the Z position, and also coincides with the center line 7a penetrating the non-counterbore portion of each primary conductor. It is a position to do. The position in the Y direction is a position where each magnetosensitive surface 8 of each magnetoelectric conversion element 3 coincides with the center line 7 b of each primary conductor 4.

Next, the operation of the current sensor 2 will be described. In FIG. 4, when the magnetoelectric conversion element 3a is installed at the position described above, the magnetic flux line 6a around the primary conductor 4a and a part of the magnetic flux vector 9a at the time of applying the current to be measured are shown on the AA cross section (YZ plane) for one phase. It is shown. In the counterbore part 5a of the primary conductor 4a, the cross section of the primary conductor 4a has a concave shape. Therefore, the magnetic flux line 6a becomes a curved ellipse in the vicinity of the primary conductor 4a. At that time, the magnetic flux vector 9 on the center line 7a outside the primary conductor 4a is substantially relative to the center line 7a, although it depends on the shape of the counterbore part 5, as indicated by, for example, the magnetic flux vector 9a1 and the magnetic flux vector 9a2. The direction is the Z direction, that is, the direction perpendicular to the Y direction. However, on the magnetic sensitive surface 8a, a magnetic flux vector 9a coinciding with the magnetic sensitive direction is applied.
FIG. 5 shows the magnetosensitive surface 8a. The magnetic flux vector 9 in FIG. When a current to be measured flows through each primary conductor 4, a magnetic flux is generated around each primary conductor 4 according to the magnitude of the current to be measured. In FIG. 3, an example of the magnetic flux is indicated by a broken magnetic flux line 6. The conductor 4a becomes the magnetic flux line 6a, the primary conductor 4b becomes the magnetic flux line 6b, and the primary conductor 4c becomes the magnetic flux line 6c. The magnetic flux vector 9 on the magnetosensitive surface 8a of the magnetoelectric transducer 3a caused by the magnetic flux lines 6 generated in each primary conductor 4 is the primary conductor 4a magnetic flux vector 9a, the primary conductor 4b magnetic flux vector 9b, and the primary conductor. 4c becomes the magnetic flux vector 9c. As can be seen from FIG. 5, since the magnetic flux vector 9b and the magnetic flux vector 9c are in the in-plane direction with respect to the magnetic sensitive direction of the magnetic sensitive surface 8a, the magnetoelectric conversion element 3a is insensitive and not detected. Is only the magnetic flux vector 9a by the primary conductor 4a which coincides with the out-of-plane direction of the magnetic sensitive surface 8a. Thus, when the magnetosensitive surface 8a of the magnetoelectric transducer 3a substantially coincides with the center line 7a passing through the primary conductor 4b and the primary conductor 4c, the magnetic flux vector 9b and the magnetic flux vector 9c generated in the primary conductor 4b and the primary conductor 4c. Is in a direction perpendicular to the magnetic sensing direction of the magnetic sensing surface 8a, that is, the insensitive direction, and thus does not affect the detection of the current to be measured of the primary conductor 3a. That is, the magnetic flux generated by the current to be measured to be detected can be accurately captured without being influenced by other phases.
Here, only the operation for the current sensor 2a in the primary conductor 4a has been described with reference to FIGS. 3, 4, and 5. However, neither the current sensor 2b nor the current sensor 2c is affected by other phases. The same applies to.
In this embodiment, the counterbore part is installed on the upper surface side of the primary conductor. However, the counterbore part may be installed on the lower surface side of the primary conductor, and the shape of the counterbore part is limited to a square shape. It may be a round shape or the like. In the present embodiment, an example of detecting a three-phase AC current has been described. However, the present invention is not limited to three phases, and a plurality of primary conductors may be installed in a plurality of phases. Even if the primary conductors 4 are arranged substantially in parallel so as not to overlap with each other in the longitudinal direction, they are not affected by other phases. In the present embodiment, the magnetosensitive surface 8 of each magnetoelectric conversion element 3 is not located at the center inside each magnetoelectric conversion element 3, but is shifted from the center. However, the present invention is not limited to this. Alternatively, the magnetosensitive surface 8 may be located in the center of each magnetoelectric conversion element 3.

Next, the position in the Z direction where the magnetoelectric conversion element 3 is installed is the same as in FIG. 3, and an example in which the position in the Y direction is varied will be described. In the above example, in the Y direction, the magnetosensitive surface 8a of the magnetoelectric conversion element 3a is set to a position coincident with the center line 7b of the primary conductor 4a. However, the magnetosensitive surface 8a of the magnetoelectric conversion element 3a is primary in the counterbore portion 5a. The position does not coincide with the center line 7b of the conductor 4a. FIG. 6 shows the magnetic flux vector 9 on the magnetosensitive surface 8a of the magnetoelectric conversion element 3a when the magnetoelectric conversion element 3a is installed at a position not coincident with the center line 7b. The magnetic flux vectors 9b and 9c generated in the primary conductor 4b and the primary conductor 4c are in the in-plane direction with respect to the magnetic sensitive surface 8a, and do not affect the current measurement of the primary conductor 3a as in FIG. It is. Since the magnetosensitive surface 8a of the magnetoelectric transducer 3a does not coincide with the center line 7b of the primary conductor 4a, the direction of the magnetic flux vector 9a by the primary conductor 4a does not coincide with the Y direction and is an angle with respect to the Y axis. It becomes. Therefore, on the magnetic sensing surface 8a of the magnetoelectric transducer 3a, the magnetic flux applied in the Y direction, which is the magnetic sensing direction, becomes a magnetic flux vector 9a 'obtained by resolving the magnetic flux vector 9a in the Y direction, and a value obtained by lowering the magnetic flux vector 9a. Become. Therefore, even if the current to be measured is a large current, the magnetic flux applied to the magnetoelectric conversion element 3a is suppressed, without worrying about output saturation, etc., and without increasing the external dimensions of the current detection device. , Large current can be easily detected.
In the present embodiment, an example of detecting the current of a three-phase alternating current has been described. However, the present invention is not limited to three phases, and a plurality of primary conductors may be installed in a plurality of phases.

  As described above, according to the first embodiment, the primary conductors are arranged in the same plane so that the counterbore portions provided with the magnetoelectric conversion elements overlap each other in the longitudinal direction of the primary conductors. Even when arranged substantially in parallel, the influence of the magnetic field generated by the current of the other phase when detecting the multiphase current can be reduced, and the current to be measured can be detected with high accuracy.

  In addition, since the magnetoelectric transducer with the magnetosensitive direction being out-of-plane direction is installed so that it fits in the counterbore part, the size of the multiphase current detection device does not increase in the height direction, and it is small and thin. Can be configured.

  In addition, since the magnetic flux applied in the magnetic sensing direction of the magnetoelectric conversion element can be varied depending on the installation position of the magnetoelectric conversion element, a large current can be easily detected, and a multiphase current detection device including a primary conductor The structure can be made compact.

Embodiment 2. FIG.
FIG. 7 shows a perspective view of only the primary conductor 4 in the multiphase current detection apparatus 1 according to Embodiment 2 of the present invention. FIG. 8 is a plan view (XY plane) of the multiphase current detection apparatus 1. 9 is a cross-sectional view showing the AA cross section (YZ plane) in FIGS. 7 and 8. FIG. 10 is a magnetic flux diagram at the time of applying the current to be measured in the AA cross section (YZ plane) for one phase in FIGS. is there. The multiphase current detection device 1 shown in the figure is an example in which, for example, in a three-phase alternating current, each phase current is detected by a current sensor 2 installed for each phase. The magnetoelectric conversion element 3 and the primary conductor 4 are configured, and the primary conductor 4 is provided with a U-shaped forming portion 10. In the figure, the primary conductor 4 is shown only in the vicinity of the current sensor 2 for the sake of simplicity, as in the first embodiment, but is actually extended and connected to a power source and various devices. In the actual apparatus configuration, the magnetoelectric conversion element 3 is installed connected to a printed circuit board or the like, but is omitted here and will be described in another embodiment.
In the second embodiment, a U-shaped forming portion 10 is formed on a part of each primary conductor 4, one magnetoelectric conversion element 3 is disposed in each U-shaped forming portion 10, and each U-shaped forming portion 10 is Each primary conductor 4 is arranged substantially in parallel so as to overlap with the longitudinal direction of each primary conductor 4.
The second embodiment is a configuration in which the counterbore portion provided in each primary conductor 4 in the first embodiment is changed to a U-shaped formation portion, and the redundant portions in other configurations and operations are omitted.

The configuration of the current sensor 2 for one phase will be described first from the primary conductor 4. A U-shaped forming portion 10 is formed on a part of each primary conductor 4. Although the cross-sectional area of the U-shaped forming part 10 depends on the type of the magnetoelectric conversion element to be used, it is generally determined according to the magnetic flux density to be applied to the magnetoelectric conversion element 3, that is, the range of the current to be detected. If a large current value is to be detected, it is desirable that the cross-sectional area is large, that is, that the U-shape is large in order to reduce the current density in the vicinity of the U-shaped portion 10, and if a small current value is to be detected, U In order to increase the current density in the vicinity of the character forming portion 10, it is desirable that the cross-sectional area is small, that is, the U-shape is small. Further, as is apparent from the plan view of FIG. 8, the U-shaped portions 10 are aligned so that the positions of the U-shaped portions 10 overlap in the longitudinal direction of the primary conductor 4, that is, the X direction here. Installed. Such a primary conductor 4 is produced by, for example, a combination of cutting a metal plate material such as copper into a convex shape and bending the convex portion into a U shape, or casting. The length in the X direction of the U-shaped portion 10 is at least five times the length in the X direction of the magnetoelectric transducer 3 to be installed in order to allow the current to be measured to flow stably through the U-shaped portion 10. It is desirable that
At least one magnetoelectric conversion element 3 is installed inside each U-shaped forming portion 10 and constitutes a current sensor 2. When a current to be measured is applied to the primary conductor 4, a magnetic flux is generated around the primary conductor 4. Even in this embodiment, the magnetic flux in the Y direction is measured out of the plane of the magnetoelectric transducer 3. As the element, a Hall element or a Hall IC in which a Hall element and a processing circuit are integrated is used, but the element is not limited thereto. The position where the magnetoelectric conversion element 3 is installed will be described with reference to FIG. 9. To do. The position in the Y direction is a position where each magnetosensitive surface 8 of each magnetoelectric conversion element 3 coincides with the center line 7 b of each U-shaped portion 10.

Next, the operation of the current sensor 2 will be described with reference to FIGS. In FIG. 10, when the magnetoelectric conversion element 3a is installed at the position described above, the magnetic flux line 6a around the primary conductor 4a and a part of the magnetic flux vector 9a when the current to be measured is applied are taken along the AA cross section (YZ plane) for one phase. It is shown. In the U-shaped formation part 10a of the primary conductor 4a, the cross section has a concave shape. Therefore, the magnetic flux line 6a becomes a curved elliptical shape in the vicinity of the U-shaped forming portion 10a. At that time, the magnetic flux vector 9 on the center line 7a penetrating the center of gravity of the U-shaped portion 10a is generally based on the shape of the U-shaped portion 10a as shown by the magnetic flux vector 9a1 and the magnetic flux vector 9a2, for example. The center line 7a is in the Z direction, that is, the direction perpendicular to the Y direction. However, on the magnetic sensitive surface 8a, a magnetic flux vector 9a coinciding with the magnetic sensitive direction is applied.
The operation in three phases will be described with reference to FIG. The magnetic flux vector explanatory diagram is the same as FIG. When a current to be measured flows through each primary conductor 4, a magnetic flux is generated around each primary conductor 4 according to the magnitude of the current to be measured. When an example of the magnetic flux is indicated by a broken magnetic flux line 6, the primary conductor 4 a The line 6a and the primary conductor 4b become the magnetic flux line 6b, and the primary conductor 4c becomes the magnetic flux line 6c. The magnetic flux vector 9 on the magnetosensitive surface 8a of the magnetoelectric transducer 3a caused by the magnetic flux lines 6 generated in each primary conductor 4 is the primary conductor 4a magnetic flux vector 9a, the primary conductor 4b magnetic flux vector 9b, and the primary conductor. 4c becomes the magnetic flux vector 9c. As can be seen from FIG. 5, since the magnetic flux vector 9b and the magnetic flux vector 9c are in the in-plane direction with respect to the magnetosensitive surface 8a, the magnetoelectric transducer 3a is insensitive and is not detected. Only the magnetic flux vector 9a by the primary conductor 4a coincides with the out-of-plane direction of 8a. Thus, when the magnetosensitive surface 8a of the magnetoelectric transducer 3a coincides with the center line 7a passing through the center of gravity of the U-shaped portion 10b and the U-shaped portion 10c, the magnetic flux generated in the primary conductor 4b and the primary conductor 4c. Since the vectors 9b and 9c are in the in-plane direction, that is, the insensitive direction with respect to the magnetic sensitive surface 8a, they do not affect the current measurement of the primary conductor 3a. That is, the magnetic flux generated by the current to be measured to be detected can be accurately captured without being influenced by other phases.
Here, only the operation of the current sensor 2a in the primary conductor 4a has been described with reference to FIGS. 5, 9, and 10. However, the current sensor 2b and the current sensor 2c are installed at positions overlapping each other in the X direction. However, the same applies to the configuration that is not affected by other phases.
In this embodiment, the U-shaped forming part is installed on a part of the primary conductor, but the reverse U-shaped forming part, that is, the convex U-shaped forming part is installed on a part of the primary conductor. In addition, the shape of the U-shaped bottom portion of the U-shaped forming portion is not limited to the arc shape, and may be a square shape or the like. In the present embodiment, a three-phase AC current detection example has been described. However, the present invention is not limited to three phases, and a plurality of primary conductors may be installed in a plurality of phases. Even if the primary conductors 4 are arranged substantially in parallel so as not to overlap with the longitudinal direction of the four, they are not affected by other phases. However, when the U-shaped portion 10 does not overlap, the magnetosensitive surface 8 of the magnetoelectric conversion element 3 installed in the U-shaped portion 10 coincides with the center line penetrating the non-U-shaped portion of the other primary conductor 4. It is assumed that this is configured.

  FIG. 11 shows a perspective view of only another primary conductor 4 in the multiphase current detection device 1 according to Embodiment 2 of the present invention. Except for the configuration of the primary conductor, the overlapping parts in other configurations are as follows. Omitted. In the previous example shown in FIG. 7 and the like, the U-shaped forming part is formed by processing the convex part which is a part of the primary conductor, but in the example of FIG. 11, the U-shaped forming part is formed in advance. The primary conductor is connected to both ends thereof. In particular, the connection method is not shown in the figure, but it is desirable to connect in close contact in order to prevent heat generation by screwing or brazing, but it is not limited to these methods. In the previous example, there is an advantage that the primary conductor and the U-shaped forming portion are integrated, but when cut out from the plate material, a portion to be discarded is inevitably generated and wasted. In the example of FIG. 11, man-hours are generated in the connection between the U-shaped forming portion and the primary conductor, but it is possible to prevent waste during material removal.

  As described above, according to the second embodiment, the primary conductors are arranged on the same plane so that the U-shaped portions provided with the magnetoelectric transducers overlap each other in the longitudinal direction of the primary conductors. Even when arranged in parallel, the influence of the magnetic field generated by the current of the other phase when detecting the multiphase current can be reduced, and the current to be measured can be detected with high accuracy.

  In addition, since the magnetoelectric conversion element having a magnetosensitive direction in the out-of-plane direction is installed so as to be accommodated in the U-shaped portion, the size of the multiphase current detection device can be reduced in size in the width direction without increasing the size. .

Embodiment 3 FIG.
12 is a perspective view of a multiphase current detection device 1 according to Embodiment 3 of the present invention. FIG. 13 is a plan view (XY plane) of the multiphase current detection device 1, and FIG. It is sectional drawing which shows the AA cross section (YZ surface) in FIG. The multiphase current detection device 1 shown in the figure is an example in which, for example, in a three-phase alternating current, each phase current is detected by a current sensor 2 installed for each phase. A primary conductor 4 provided with a counterbore part 5 and a magnetoelectric conversion element 3 are configured. The magnetoelectric conversion element 3 is connected to a sensor substrate 11 provided on the upper part of the primary conductor 4. In the drawing, the primary conductor 4 is shown only in the vicinity of the current sensor 2 for the sake of simplicity. However, in the present embodiment 3, each primary conductor 4 is assumed to be extended and connected to a power source, various devices, and the like. A counterbore part 5 is formed in part, one magnetoelectric conversion element 3 is arranged in each counterbore part 5, each magnetoelectric conversion element 3 is connected and fixed to the sensor substrate 11, and each counterbore part 5 is each primary The primary conductors 4 are arranged substantially in parallel so as to overlap with the longitudinal direction of the conductors 4.
The third embodiment has a configuration in which a sensor substrate is added to the first embodiment, and the overlapping portions in other configurations are omitted.

The configuration of the multiphase current detection device 1 in the present embodiment will be described. Each magnetoelectric conversion element 3 is arranged on one surface of the sensor substrate 11 via a spacer 15. The spacer 15 is provided to mechanically install each magnetoelectric conversion element 3 at the predetermined position shown in the first embodiment, and does not affect the detection of the current to be measured. It is desirable to use a magnetic member. Each magnetoelectric conversion element 3 is also electrically connected to the sensor substrate 11 via wire bonding, solder, or the like in order to connect to a sensor circuit unit 12 described later. A sensor circuit unit 12 is provided on the other surface of the sensor substrate 11 to supply voltage or current to each magnetoelectric conversion element 3 and to perform appropriate amplification or adjustment on the output voltage or output current of each magnetoelectric conversion element 3. The external terminal 13 is used for electrical connection with an external input / output terminal.
The sensor substrate 11 and the primary conductor 4 are fixed using an adhesive, a mounting member, or the like, although not particularly shown. The mounting member is not particularly limited in material, but is preferably non-magnetic and less deteriorated with time, and may be entirely or partially resin-molded in order to increase the effect of insulation and pressure resistance.
As shown in the cross-sectional view of FIG. 14, the electric field shield layer 14 having conductivity is provided on the inner layer of the sensor substrate 11. The electric field shield layer 14 is for removing or reducing electric field noise applied to the sensor circuit unit 12 as noise that degrades the performance as a current sensor, and is installed between the sensor circuit unit 12 and the primary conductor 4. If possible, it is desirable to install so as to cover the magnetoelectric conversion element 3 and the sensor circuit unit 12. The material of the electric field shield layer 14 may be conductive, for example, copper, aluminum or the like, and is connected to an electrical ground provided on the sensor substrate 11. As a form of installation, for example, a ground layer may be provided on at least one of the inner layers of the multilayer substrate.
The operation of each current sensor 2 is the same as that of the first embodiment, and is omitted because it is duplicated.

  As described above, according to the third embodiment, the primary conductors are arranged in the same plane so that the counterbore portions provided with the magnetoelectric transducers overlap each other in the longitudinal direction of the primary conductors. Even when arranged substantially in parallel, the influence of the magnetic field generated by the current of the other phase when detecting the multiphase current can be reduced, and the current to be measured can be detected with high accuracy.

  In addition, since the magnetoelectric transducer having a magnetosensitive direction that is out-of-plane direction is installed in the counterbore part and connected to the sensor substrate 11 so as to be accommodated in the counterbore part, a multiphase current detection device in the height direction and the width direction is provided. The size can be reduced in size and thickness without increasing the size.

  In addition, at least one small sensor substrate can cope with multiple phases, the apparatus becomes small, and the manufacturing process is simplified and the cost is reduced.

  Furthermore, by providing a shield layer on the inner layer of the sensor substrate, electric field noise mainly generated from the primary conductor can be removed or reduced with respect to the sensor circuit unit, so that the sensor output is highly accurate.

DESCRIPTION OF SYMBOLS 1 Detection apparatus of multiphase current, 2 Current sensor, 3 Magnetoelectric conversion element, 4 Primary conductor, 5 Counterbore part, 6 Magnetic flux line, 7 Center line, 8 Magnetic sensing surface, 9 Magnetic flux vector, 10 U-shaped formation part, 11 Sensor Board, 12 Sensor circuit, 13 External terminal, 14 Shield layer, 15 Spacer

Claims (5)

A current to be measured is applied to each of the plurality of primary conductors each having at least one counterbore, and the current to be measured in the out-of-plane direction of the magnetosensitive surface inside at least one of the counterbore of each primary conductor. And at least one magnetoelectric conversion element installed so that the magnetic flux generated by
While the center position of the cross section of the primary conductor of the part different from the counterbore part and the magnetosensitive surface of the magnetoelectric conversion element substantially coincide,
The multi-phase current detection device, wherein the plurality of primary conductors are substantially parallel to each other and arranged in the same plane. A plurality of primary conductors each having a current to be measured, each having at least one U-shaped portion, and an out-of-plane direction of the magnetosensitive surface within at least one U-shaped portion of each primary conductor And at least one magnetoelectric transducer installed so that a magnetic flux generated by the current to be measured is applied to
While the central position of the cross section of the primary conductor at a site different from the U-shaped portion and the magnetosensitive surface of the magnetoelectric transducer substantially coincide,
The multi-phase current detection device, wherein the plurality of primary conductors are substantially parallel to each other and arranged in the same plane. A plurality of primary conductors each having a current to be measured, each having at least one U-shaped portion, and an out-of-plane direction of the magnetosensitive surface within at least one U-shaped portion of each primary conductor And at least one magnetoelectric transducer installed so that a magnetic flux generated by the current to be measured is applied to
The center of gravity position of the cross section of the U-shaped portion and the magnetosensitive surface of the magnetoelectric transducer substantially coincide with each other,
The multi-phase current detection device, wherein the plurality of primary conductors are substantially parallel to each other and arranged in the same plane.   Each of the magnetoelectric conversion elements is installed on at least one sensor substrate, and the sensor substrate holds the magnetoelectric conversion element at a predetermined position of the counterbore part or the U-shaped formation part and is fixed on the primary conductor. The multiphase current detection device according to claim 1, 2, or 3.   The multiphase current detection device according to claim 4, wherein a conductive shield layer is provided inside the sensor substrate, and a sensor circuit portion is provided on a surface of the sensor substrate.

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