Current sensor and electrical control device

Abstract

The present invention provides a current sensor for detecting magnetism generated by a conductor in which current flows in a first direction, and is characterized in that it has a magnetic detection portion capable of detecting magnetism, a magnetic collecting core, and a magnetic shield. The magnetic collecting core includes: a first core portion, which is substantially parallel to the first direction; a second core portion and a third core portion, which are respectively continuous with the two ends of the first core portion in a second direction orthogonal to the first direction. The second core portion and the third core portion extend from the ends of the first core portion in a manner along a third direction orthogonal to the first direction and the second direction, respectively. The magnetic detection portion has a magnetically sensitive direction in the second direction, and is located in a core gap sandwiched by the end of the second core portion and the end of the third core portion in the third direction. The magnetic shield includes a plate-shaped shield portion positioned so as to overlap with the core gap when viewed along the third direction.

Description

Technical Field

[0001] The invention relates to a current sensor and an electric control device. Background Art

[0002] In recent years, current sensors are used in hybrid electric vehicles (HEV) or electric vehicles (EV) to measure the remaining amount of batteries, measure the drive current of motors, and power control devices such as converters and inverters. As such current sensors, current sensors with magnetic sensors are known, which include magnetic detection elements that can detect the magnetic field generated by the flow of current in conductors such as bus bars. In the current sensor, for example, the current flowing in a conductor such as a bus bar is detected in a non-contact state by a magnetoresistance effect element such as an AMR element, a GMR element, a TMR element, or a magnetic detection element such as a Hall element.

[0003] At present, it is known that the current sensor has an annular magnetic core having a gap (gap), and a magnetic sensor including a magnetic detection element is arranged in the gap (see Patent Document 1). With such a structure, the magnetic flux generated from the conductor can be gathered on the magnetic core, and the magnetic flux gathered by the magnetic core can be applied to the magnetic detection element arranged in the gap.

[0004] Prior art literature

[0005] Non-patent literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2019-78542 Summary of the invention

[0007] Problems to be solved by the invention

[0008] In the current sensor disclosed in Patent Document 1, if the current flowing in the conductor becomes relatively large, the magnetic field generated from the conductor becomes strong, and thus the magnetic core is easily magnetically saturated, so the linearity of the output of the magnetic sensor may deteriorate. If the gap (interval) of the magnetic core is enlarged or the volume of the magnetic core is increased, the deterioration of the linearity of the output of the magnetic sensor can be improved. However, if the gap (interval) of the magnetic core is enlarged, the magnetic field other than the magnetic field generated by the conductor (hereinafter sometimes referred to as "interference magnetic field") is easily applied to the magnetic detection element, and the detection accuracy of the current sensor may be reduced.

[0009] In view of the above-mentioned problems, an object of the present invention is to provide a current sensor and an electric control device capable of suppressing the influence of a disturbance magnetic field.

[0010] Technical solutions to solve problems

[0011] In order to solve the above-mentioned problems, the present invention provides a current sensor, which is used to detect magnetism generated by a conductor in which current flows in a first direction, and is characterized in that it has a magnetic detection part that can detect the magnetism, a magnetic collecting core, and a magnetic shield, the magnetic collecting core including: a first core part, which is substantially parallel to the first direction; a second core part and a third core part, which are respectively continuous with the two ends of the first core part in a second direction orthogonal to the first direction, the second core part and the third core part respectively extend from the end of the first core part in a manner along a third direction orthogonal to the first direction and the second direction, the magnetic detection part has a magnetic sensitive direction in the second direction, a core gap sandwiched near the end of the second core part and the end of the third core part in the third direction, and the magnetic shield includes a plate-shaped shielding part positioned in a manner overlapping with the core gap when viewed along the third direction.

[0012] Alternatively, the magnetic core further includes a fourth core portion continuous with the vicinity of the end of the second core portion and a fifth core portion continuous with the vicinity of the end of the third core portion, and the fourth core portion and the fifth core portion extend in a mutually approaching manner along the second direction. The conductor may be a plate-like body with the thickness direction set to the second direction and extending along the first direction, or may be a plate-like body with the thickness direction set to the third direction and extending along the first direction.

[0013] It may also be that the magnetic shield includes a first shield portion and a second shield portion which are respectively continuous with both ends of the plate-shaped shield portion along the first direction and extend along the third direction, and when viewed along the first direction, the magnetic detection portion is located in the core gap clamped by the first shield portion and the second shield portion.

[0014] Alternatively, the plate-shaped shielding portion may be formed with a slit portion penetrating in the third direction, and when viewed along the third direction, the long side direction of the slit portion may be substantially consistent with the first direction, and the long side direction of the slit portion may be substantially consistent with the second direction. A plurality of slit portions may also be formed in the plate-shaped shielding portion.

[0015] Alternatively, the iron loss of the constituent material of the magnetic shield is greater than the iron loss of the constituent material of the magnetic core, the magnetic detection unit may include a magnetoresistance effect element or a Hall element, and the magnetoresistance effect element may be a GMR element or a TMR element. The conductor may also be arranged to penetrate the space formed by the first core portion, the second core portion, and the third core portion of the magnetic core along the first direction.

[0016] The present invention provides an electrical control device, characterized by comprising the above-mentioned current sensor.

[0017] Effects of the Invention

[0018] According to the present invention, it is possible to provide a current sensor and an electric control device capable of suppressing the influence of a disturbance magnetic field. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a perspective view showing a schematic structure of a first form of a current sensor according to an embodiment of the present invention.

[0020] Figure 2 It is a side view showing a schematic structure of a first form of the current sensor according to the embodiment of the present invention.

[0021] Figure 3 It is a side view showing a schematic structure of a first form of the current sensor according to the embodiment of the present invention.

[0022] Figure 4 It is a partially enlarged cutaway end view showing a schematic structure of a first form of the current sensor according to the embodiment of the present invention.

[0023] Figure 5A This is a side view for explaining the influence of the X-direction disturbance magnetic field on a current sensor having a magnetic collecting core with a relatively narrow core gap and no magnetic shield.

[0024] Figure 5B This is a side view for explaining the influence of the Y-direction disturbance magnetic field on a current sensor having a magnetic collecting core with a relatively narrow core gap and no magnetic shield.

[0025] Fig. 6A This is a side view for explaining the influence of the X-direction disturbance magnetic field on a current sensor having a magnetic collecting core with a relatively wide core gap and no magnetic shield.

[0026] Figure 6B This is a side view for explaining the influence of the Y-direction disturbance magnetic field on a current sensor having a magnetic collecting core with a relatively wide core gap and no magnetic shield.

[0027] Figure 6C This is a side view for explaining the influence of the X-direction disturbance magnetic field on the current sensor having the magnetic collecting core and the magnetic shield with a relatively wide core gap.

[0028] Figure 7 This is a block diagram showing a schematic configuration of a current sensor according to an embodiment of the present invention.

[0029] Figure 8 : is a circuit diagram schematically showing a circuit configuration of a magnetic detection unit in an embodiment of the present invention.

[0030] Fig. 9This is a perspective view showing a schematic structure of one form of a magnetoresistive effect element in an embodiment of the present invention.

[0031] Fig.10 This is a cut-away end view showing a schematic structure of one form of a magnetoresistive effect element in an embodiment of the present invention.

[0032] Fig.11A It is a perspective view showing a schematic structure of a modified example of the first aspect of the current sensor according to the embodiment of the present invention.

[0033] Fig. 11B It is a perspective view showing a schematic structure of a modified example of the first aspect of the current sensor according to the embodiment of the present invention.

[0034] Fig. 11C It is a perspective view showing a schematic structure of a modified example of the first aspect of the current sensor according to the embodiment of the present invention.

[0035] Fig.11D It is a perspective view showing a schematic structure of a modified example of the first aspect of the current sensor according to the embodiment of the present invention.

[0036] Fig. 12A It is a side view for explaining the influence of the disturbance magnetic field in the Y direction on the current sensor according to the embodiment of the present invention.

[0037] Fig. 12B It is a side view for explaining the influence of the disturbance magnetic field in the Y direction in the modification of the current sensor according to the embodiment of the present invention.

[0038] Fig. 12C It is a side view for explaining the influence of the disturbance magnetic field in the Y direction in the modification of the current sensor according to the embodiment of the present invention.

[0039] Fig.13 It is a perspective view showing a schematic structure of a second form of the current sensor according to the embodiment of the present invention.

[0040] Fig.14 It is a side view showing a schematic structure of a second form of the current sensor according to the embodiment of the present invention.

[0041] Fig.15 It is a side view showing a schematic structure of a second form of the current sensor according to the embodiment of the present invention.

[0042] Fig.16 It is a partially enlarged cutaway end view showing a schematic structure of a second form of the current sensor according to the embodiment of the present invention.

[0043] Fig.17AIt is a side view for explaining the influence of the disturbance magnetic field in the Y direction in the second aspect of the current sensor according to the embodiment of the present invention.

[0044] Fig. 17B This is a side view for explaining the influence of the disturbance magnetic field in the X direction in the second aspect of the current sensor according to the embodiment of the present invention.

[0045] Fig.18A It is a perspective view showing a schematic structure of a modified example of the second aspect of the current sensor according to the embodiment of the present invention.

[0046] Fig.18B It is a perspective view showing a schematic structure of a modified example of the second aspect of the current sensor according to the embodiment of the present invention.

[0047] Fig. 18C It is a perspective view showing a schematic structure of a modified example of the second aspect of the current sensor according to the embodiment of the present invention.

[0048] Fig.18D It is a perspective view showing a schematic structure of a modified example of the second aspect of the current sensor according to the embodiment of the present invention.

[0049] Fig.19 It is a side view for explaining the influence of the disturbance magnetic field in the Y direction in the modification of the second aspect of the current sensor in the embodiment of the present invention.

[0050] Fig. 20 It is a perspective view showing a schematic structure of a third form of the current sensor according to the embodiment of the present invention.

[0051] Fig.21 It is a side view showing a schematic structure of a third form of the current sensor according to the embodiment of the present invention.

[0052] Fig. 22 It is a side view showing a schematic structure of a third form of the current sensor according to the embodiment of the present invention.

[0053] Fig.23A It is a perspective view showing a schematic structure of a modified example of the third aspect of the current sensor according to the embodiment of the present invention.

[0054] Fig. 23B It is a perspective view showing a schematic structure of a modified example of the third aspect of the current sensor according to the embodiment of the present invention.

[0055] Fig.23C It is a perspective view showing a schematic structure of a modified example of the third aspect of the current sensor according to the embodiment of the present invention.

[0056] Fig.23DIt is a perspective view showing a schematic structure of a modified example of the third aspect of the current sensor according to the embodiment of the present invention.

[0057] Fig.24 It is a perspective view showing a schematic structure of a fourth form of the current sensor according to the embodiment of the present invention.

[0058] Fig.25 It is a side view showing a schematic structure of a fourth form of the current sensor according to the embodiment of the present invention.

[0059] Fig.26 It is a side view showing a schematic structure of a fourth form of the current sensor according to the embodiment of the present invention.

[0060] Fig.27A It is a perspective view showing a schematic structure of a modification example of the fourth aspect of the current sensor according to the embodiment of the present invention.

[0061] Fig.27B It is a perspective view showing a schematic structure of a modification example of the fourth aspect of the current sensor according to the embodiment of the present invention.

[0062] Fig.27C It is a perspective view showing a schematic structure of a modification example of the fourth aspect of the current sensor according to the embodiment of the present invention.

[0063] Fig.27D It is a perspective view showing a schematic structure of a modification example of the fourth aspect of the current sensor according to the embodiment of the present invention.

[0064] Fig.28 It is a perspective view showing a schematic structure of a fifth form of the current sensor according to the embodiment of the present invention.

[0065] Fig.29 It is a side view showing a schematic structure of a fifth form of the current sensor according to the embodiment of the present invention.

[0066] Fig.30 It is a side view showing a schematic structure of a fifth form of the current sensor according to the embodiment of the present invention.

[0067] Fig.31A It is a perspective view showing a schematic structure of a modification example of the fifth aspect of the current sensor according to the embodiment of the present invention.

[0068] Fig.31B It is a perspective view showing a schematic structure of a modification example of the fifth aspect of the current sensor according to the embodiment of the present invention.

[0069] Fig.31C It is a perspective view showing a schematic structure of a modification example of the fifth aspect of the current sensor according to the embodiment of the present invention.

[0070] Fig.31D It is a perspective view showing a schematic structure of a modification example of the fifth aspect of the current sensor according to the embodiment of the present invention.

[0071] Fig.32 This is a graph showing frequency characteristics caused by the difference in iron loss between the constituent materials of the magnetic collecting core and the constituent materials of the magnetic shield in the current sensor. DETAILED DESCRIPTION

[0072] An embodiment of the present invention will be described with reference to the drawings. Figure 1 is a perspective view showing a schematic structure of a first form of the current sensor according to the present embodiment, Figure 2 is a side view showing a schematic structure of a first form of the current sensor according to the present embodiment, Figure 3 is a side view showing a schematic structure of a first form of the current sensor according to the present embodiment, Figure 4 It is a partially enlarged cutaway end view showing a schematic structure of a first form of the current sensor according to the present embodiment.

[0073] Before describing the present embodiment, “a first direction, a second direction, and a third direction” are defined in some drawings as needed. Here, the first direction is the direction of the current flowing in the conductor. The second direction is a direction orthogonal to the first direction, and is the width direction of the conductor in the first to third modes and the fifth mode, and is the thickness direction of the conductor in the fourth mode. The third direction is a direction orthogonal to the first direction and the second direction, and is the thickness direction of the conductor in the first to third modes and the fifth mode, and is the width direction of the conductor in the fourth mode. In addition, in this specification and the drawings, the first direction is sometimes referred to as the “Z direction”, the second direction is sometimes referred to as the “X direction”, and the third direction is sometimes referred to as the “Y direction”.

[0074] like Figure 1 to Figure 4 As shown, a first aspect of the current sensor 1 according to the present embodiment includes a magnetic detection unit 2 capable of detecting magnetism, a magnetic collecting core 3 , a magnetic shield 4 , and a conductor 5 through which a current flows in the Z direction.

[0075] The magnetic core 3 includes a first core portion 31 substantially parallel to the Z direction, a second core portion 32 and a third core portion 33 which are continuous with both ends 31A and 31B of the first core portion 31 in the X direction and extend in the Y direction (+Y direction), a fourth core portion 34 which is continuous with the end 32A of the second core portion 32 in the Y direction and extend in the X direction (-X direction), and a fifth core portion 35 which is continuous with the end 33A of the third core portion 33 in the Y direction and extend in the X direction (+X direction). The fourth core portion 34 and the fifth core portion 35 extend from the end 32A of the second core portion 32 and the end 33A of the third core portion 33 in the X direction so that their end faces are close to each other. The gap (space) sandwiched between the end faces of the fourth core portion 34 and the end faces of the fifth core portion 35 which are opposed to each other is the core gap CG. That is, the magnetic core 3 is annular with the core gap CG, and is a substantially C-shaped core when viewed in the Z direction.

[0076] In the present embodiment, the end 31A of the first core portion 31 and the continuous portion of the second core portion 32, the end 31B of the first core portion 31 and the continuous portion of the third core portion 33, the end 32A of the second core portion 32 and the continuous portion of the fourth core portion 34, and the end 33A of the third core portion 33 and the continuous portion of the fifth core portion 35 of the magnetic core 3 all have a curved shape (rounded shape), but are not limited to this form. For example, these continuous portions can be a zigzag shape (a shape with an angle), or a C-chamfered shape with chamfered corners.

[0077] The length L of the core gap CG in the X direction CG (The distance between the end surface of the fourth core portion 34 and the end surface of the fifth core portion 35 in the X direction) may be, for example, 6 mm or more, or may be about 6 to 12 mm. CG When the thickness is 6 mm or more, the effect of the current sensor 1 of the present embodiment having the magnetic shield 4 , that is, the effect of suppressing the application of a disturbance magnetic field to the magnetic detection unit 2 by the magnetic shield 4 can be effectively achieved.

[0078] Assuming that the current sensor 1 of this embodiment does not include the magnetic shield 4, if the length LCG of the core gap CG in the X direction is relatively small, the end surface of the fourth core portion 34 and the end surface of the fifth core portion 35 are close to the magnetic detection portion 2, then the interference magnetic field H in the X direction is x And the interfering magnetic field H in the Y direction Y are absorbed by the magnetic core 3 and are difficult to be applied to the magnetic detection part 2 (refer to Figure 5A and Figure 5B ). That is, the current sensor is not easily affected by the interfering magnetic field H x , H YOn the other hand, when the current flowing in the conductor 5 increases, the magnetic core 3 is easily magnetically saturated, and the linearity of the output of the magnetic detection unit 2 may deteriorate. In order to improve the linearity of the output of the magnetic detection unit 2, if the length LCG of the core gap CG in the X direction is relatively large (for example, 6 mm or more), and the end face of the fourth core 34 and the end face of the fifth core 35 are separated from the magnetic detection unit 2, although the magnetic core 3 is not easy to be magnetically saturated, the interference magnetic field H in the X direction is reduced. x And the interfering magnetic field H in the Y direction Y are easily applied to the magnetic detection unit 2 (refer to Fig. 6A and Figure 6B As in the current sensor 1 of this embodiment, by providing the magnetic shield 4 so as to overlap with the core gap CG when viewed along the Y direction, it is possible to block at least the disturbance magnetic field H in the X direction. x Lead to the magnetic core 3 and the magnetic shield 4 (refer to Figure 6C ). Therefore, it is possible to suppress the disturbance magnetic field H in at least the X direction. x Applied to the magnetic detection unit 2.

[0079] The width W of the magnetic core 3 in the Z direction 3 In the current sensor 1 of the present embodiment, the magnetic detection unit 2 is arranged in the core gap CG of the magnetic core 3. However, if the width W 3 If the width W is relatively small (e.g., less than 5 mm), the magnetic flux generated by the conductor 5 may easily cause the magnetic core 3 to be magnetically saturated. 3 If the current sensor 1 is relatively large, the size of the current sensor 1 will be relatively large.

[0080] The length G of the gap between the magnetic shield 4 and the magnetic collecting core 3 in the Y direction is 34 For example, it may be less than 3 mm, or may be about 1 to 2 mm. 34 If it exceeds 3mm, the interfering magnetic field H in the X direction x There is a possibility that the magnetic field may pass through the gap and be applied to the magnetic detection unit 2. In addition, if the length G of the gap is 34 If it is relatively short (for example, less than 1 mm), a magnetic path is formed from the magnetic core 3 to the magnetic shield 4. Since the magnetic flux easily flows to the magnetic shield 4, the magnetic core 3 is easily magnetically saturated, and the magnetic flux to be detected by the magnetic detection unit 2 may be reduced.

[0081] The conductor 5 made of copper or the like is a plate-like body with its long side direction substantially parallel to the Z direction and its thickness direction substantially parallel to the Y direction, and is provided in the annular magnetic collecting core 3 having the core gap CG so as to penetrate along the Z direction. The long side direction of the conductor 5 only needs to be substantially parallel to the Z direction, for example, the axis of the conductor 5 (the line passing through the center of the conductor 5) only needs to intersect with the Z direction at an angle of 2° or less. In addition, the thickness direction of the conductor 5 only needs to be substantially parallel to the Y direction, for example, only needs to intersect with the Y direction at an angle of 2° or less.

[0082] The magnetic detection unit 2 only needs to be arranged in the core gap CG. In the first mode of the current sensor 1 of the present embodiment, when the current flows in the conductor 5, a magnetic flux is generated from the conductor 5, and the magnetic flux converges on the annular magnetic collecting core 3 having the core gap CG. The magnetic collecting core 3 forms an annular shape having the core gap CG, and the magnetic collecting core 3 including the core gap CG as a whole becomes the path (magnetic circuit) of the magnetic flux. That is, the magnetic detection unit 2 arranged in the core gap CG can be located in the path (magnetic circuit) of the magnetic flux that converges on the magnetic collecting core 3. Therefore, in the present embodiment, "the magnetic detection unit 2 is arranged in the core gap CG" means that as long as the magnetic detection unit 2 is located in the above-mentioned magnetic circuit, the entire magnetic detection unit 2 can be located in the core gap CG, and a part of the magnetic detection unit 2 can also be located in the core gap CG. In addition, the detailed structure of the magnetic detection unit 2 will be described later.

[0083] The magnetic shield 4 includes a plate-shaped shield portion 41 that overlaps the core gap CG when viewed along the Y direction. Since the plate-shaped shield portion 41 overlaps the core gap CG when viewed along the Y direction, the interfering magnetic field H in the X direction x The magnetic field H in the X direction can be suppressed. x Applied to the magnetic detection unit 2.

[0084] In the present embodiment, the magnetic shield 4 is arranged such that the plate-shaped shield portion 41 completely overlaps the core gap CG when viewed in the Y direction. That is, the length L of the plate-shaped shield portion 41 of the magnetic shield 4 in the X direction is 41 As long as the length L of the core gap CG in the X direction CG The above is sufficient, and the length L of the magnetic core 3 in the X direction is sufficient. 3 The length L of the plate-shaped shielding portion 41 in the X direction is 41 When it is relatively long, the interference magnetic field H in the X direction can be increased x In addition, the length W of the plate-shaped shielding portion 41 in the Z direction is 41 It only needs to be greater than the length of the core gap CG in the Z direction, that is, the width W3 of the magnetic collecting core 3 in the Z direction. 41 As long as the length L of the core gap CG in the X directionCG +4mm or more, the length L of the magnetic core 3 in the X direction 3 The following degree is sufficient, the length W in the Z direction 41 As long as the width W of the magnetic core 3 in the Z direction 3 As described above, the width W of the magnetic core 3 in the Z direction is 3 The current sensor 1 of this embodiment is not limited to this method. For example, as long as the magnetic shield 4 can at least suppress the application of the X-direction disturbance magnetic field Hx to the magnetic detection unit 2, the plate-shaped shield 41 may not completely overlap the core gap CG.

[0085] The thickness (length in the Y direction) of the plate-shaped shielding portion 41 is not particularly limited, but may be, for example, about 1 to 3 mm. If the thickness is relatively thin (for example, less than 1 mm), the magnetic shield 4 is easily saturated, and there is a possibility of adversely affecting the linearity of the output from the current sensor 1. On the other hand, if the thickness is relatively thick, there is a possibility of affecting the manufacturing cost of the current sensor 1 and the height dimension of the current sensor 1.

[0086] The magnetic core 3 and the magnetic shield 4 can be made of soft magnetic materials such as silicon steel, electromagnetic steel, pure iron (SUY), and Permalloy, but from the perspective of low cost, silicon steel, electromagnetic steel, pure iron, etc. are preferred. The iron loss of the constituent material of the magnetic shield 4 can be greater than the iron loss of the constituent material of the magnetic core 3. A specified current flows in the conductor 5, and the magnetic field generated by the conductor 5 flows to the magnetic core 3 and the magnetic shield 4. If the frequency of the current flowing in the conductor 5 becomes higher, the frequency characteristics of the magnetic shield 4 composed of a material with relatively large iron loss deteriorate, and the magnetic field flowing to the magnetic shield 4 is relatively reduced. The frequency characteristics of the magnetic core 3 composed of a material with relatively small iron loss also deteriorate. Although the magnetic field is easy to flow, the magnetic field flowing to the magnetic core 3 is relatively increased by the amount of the magnetic field flowing to the magnetic shield 4. As a result, compared with the current sensor 1 without the magnetic shield 4, it is considered that the magnetic flux density of the magnetic field applied to the magnetic detection unit 2 is stable. This is clear in the test examples described later. However, the greater the difference in the iron loss between the two, the better the frequency characteristics are, and the attenuation of the magnetic flux density of the magnetic field applied to the magnetic detection unit 2 can be suppressed (see Fig.32). As a result, the response characteristics of the current sensor 1 with respect to the alternating current can be stabilized. The difference between the iron loss of the constituent material of the magnetic core 3 and the iron loss of the constituent material of the magnetic shield 4 is, for example, preferably greater than 2.0 W / kg, and more preferably 4.5 to 10.0 W / kg. The iron loss is a value obtained by the Epstein test method based on the provisions of JIS-C-2550 as the magnitude of the iron loss per unit weight during sinusoidal excitation with a maximum magnetic flux density of 1.5 T at a frequency of 50 Hz (average in the rolling direction and the direction perpendicular thereto). In addition, the constituent material of the magnetic core 3 may be the same type of material as the constituent material of the magnetic shield 4, or a different type of material, as long as the constituent material of the magnetic shield 4 has a smaller iron loss than that of the constituent material of the magnetic shield 4. For example, the magnetic core 3 and the magnetic shield 4 are both made of electromagnetic steel, but the iron loss of the electromagnetic steel constituting the magnetic shield 4 only needs to be greater than the iron loss of the electromagnetic steel constituting the magnetic core 3.

[0087] The current sensor 1 of the present embodiment includes a magnetic detection unit 2 and a signal processing unit 6. The signal processing unit 6 includes an A / D (analog-to-digital) conversion unit 61 that converts an analog signal output from the magnetic detection unit 2 into a digital signal, and a calculation unit 62 that performs calculation processing on the digital signal digitally converted by the A / D conversion unit 61. In addition, when the calculation processing result calculated by the calculation unit 62 is output as an analog signal, the signal processing unit 6 only needs to further include a D / A (digital-to-analog) conversion unit (not shown) on the downstream side of the calculation unit 62.

[0088] In this embodiment, the circuit structure of the magnetic detection unit 2 can be a Wheatstone bridge circuit C formed by bridging the four resistors of the first resistor R1, the second resistor R2, the third resistor R3 and the fourth resistor R4, or a circuit formed by half-bridge connection of the two resistors of the first resistor R1 and the second resistor R2. The first to fourth resistors R1 to R4 can include a single magnetoresistive effect element (AMR element, GMR element, TMR element, etc.) or a Hall element, or can include multiple magnetoresistive effect elements (AMR element, GMR element, TMR element, etc.) or Hall elements.

[0089] The Wheatstone bridge circuit C of the magnetic detection unit 2 includes a power supply port V, a ground port G, two output ports E1, E2, a first resistor R1 and a second resistor R2 connected in series, and a third resistor R3 and a fourth resistor R4 connected in series. Each end of the first resistor R1 and the third resistor R3 is connected to the power supply port V. The other end of the first resistor R1 is connected to one end of the second resistor R2 and the output port E1. The other end of the third resistor R3 is connected to one end of the fourth resistor R4 and the output port E2. The other end of each of the second resistor R2 and the fourth resistor R4 is connected to the ground port G. A power supply voltage of a specified size is applied to the power supply port V, and the ground port G is grounded.

[0090] In this embodiment, the first to fourth resistors R1 to R4 included in the Wheatstone bridge circuit C may include MR elements such as AMR elements, GMR elements, or TMR elements, or may include Hall elements. The GMR element and the TMR element include a magnetization fixed layer whose magnetization direction is fixed, a free layer whose magnetization direction changes according to the direction of the applied magnetic field, and a non-magnetic layer arranged between the magnetization fixed layer and the free layer. The AMR element includes a magnetic layer having shape anisotropy.

[0091] The MR element such as the GMR element or TMR element constituting the first to fourth resistors R1 to R4 only needs to have a plurality of first electrodes 71, a plurality of MR films 80, and a plurality of second electrodes 72. The plurality of first electrodes 71 are provided on a substrate (not shown). The first electrode 71 is also referred to as a lower lead electrode. Each first electrode 71 has an elongated shape. A gap is formed between two first electrodes 71 adjacent to each other in the long side direction of the first electrode 71. MR films 80 are provided on the upper surface of the first electrode 71 near both ends in the long side direction. The MR film 80 is substantially circular in plan view, and includes a free layer 81, a nonmagnetic layer 82, a magnetization fixed layer 83, and an antiferromagnetic layer 84 stacked in sequence from the first electrode 71 side. The free layer 81 is electrically connected to the first electrode 71. The antiferromagnetic layer 84 is made of an antiferromagnetic material, and achieves the effect of fixing the direction of magnetization of the magnetization fixed layer 83 by generating exchange coupling with the magnetization fixed layer 83. The plurality of second electrodes 72 are provided on the plurality of MR films 80. Each second electrode 72 has an elongated shape and is disposed on two first electrodes 71 adjacent to each other in the longitudinal direction of the first electrode 71, and electrically connects the antiferromagnetic layers 84 of two adjacent MR films 80 to each other. The second electrode 72 is also called an upper lead electrode. In addition, the MR film 80 may have a structure in which a free layer 81, a nonmagnetic layer 82, a magnetization pinned layer 83, and an antiferromagnetic layer 84 are stacked in this order from the second electrode 72 side. In addition, the magnetization pinned layer 83 may be set to a stacked ferromagnetic structure of a ferromagnetic layer / nonmagnetic intermediate layer / ferromagnetic layer, and a so-called self-pinned type pinned layer (Synthetic Ferri Pinned layer, SFP layer) in which two ferromagnetic layers are antiferromagnetically bonded may be formed, and the antiferromagnetic layer 84 may be omitted.

[0092] In the TMR element, the non-magnetic layer 82 is a tunnel barrier layer. In the GMR element, the non-magnetic layer 82 is a non-magnetic conductive layer. In the TMR element and the GMR element, the resistance value changes according to the angle formed by the magnetization direction of the free layer 81 relative to the magnetization direction of the magnetization fixed layer 83. When the angle is 0° (the magnetization directions are parallel to each other), the resistance value becomes the minimum, and when it is 180° (the magnetization directions are anti-parallel to each other), the resistance value becomes the maximum.

[0093] When the first to fourth resistors R1 to R4 are composed of TMR elements or GMR elements, in the Wheatstone bridge circuit C of the magnetic detection unit 2, the magnetization direction of the magnetization fixed layer 83 of the first resistor R1 and the second resistor R2 is parallel to the X direction, and the magnetization direction of the magnetization fixed layer 83 of the first resistor R1 and the magnetization fixed layer 83 of the second resistor R2 are mutually antiparallel. In addition, the magnetization direction of the magnetization fixed layer 83 of the third resistor R3 and the fourth resistor R4 is parallel to the X direction, and the magnetization direction of the magnetization fixed layer 83 of the third resistor R3 and the magnetization fixed layer 83 of the fourth resistor R4 are mutually antiparallel. In the magnetic detection unit 2, the potential difference between the output ports E1 and E2 changes according to the change in the magnetic field strength of the X-direction magnetic field generated from the conductor 5, and the signal corresponding to the potential difference between the output ports E1 and E2 is output as the sensor signal S to the signal processing unit 6. The difference detector (not shown) amplifies a signal corresponding to the potential difference between the output ports E1 and E2 , and outputs the amplified signal as a sensor signal S to the A / D converter 61 of the signal processing unit 6 .

[0094] The A / D converter 61 converts the sensor signal S (analog signal related to current) output from the magnetic detector 2 into a digital signal, and inputs the digital signal to the calculation unit 62. The calculation unit 62 performs calculation processing on the digital signal converted from the analog signal by the A / D converter 61. The calculation unit 62 is composed of, for example, a microcomputer, an AS1C (Application Specific Integrated Circuit), etc.

[0095] In the first aspect of the current sensor 1 of this embodiment, as Figures 11A to 11D As shown in FIG. 1 , a slit portion 42 penetrating in the Y direction may be formed in the plate-shaped shield portion 41 of the magnetic shield 4. The slit portion 42 may be formed so that its long side direction is substantially parallel to the X direction (see FIG. 1 ). Fig.11A ), it can also be formed so that its long side direction is substantially parallel to the Z direction (refer to Fig. 11B and Fig. 11C ), and can also be formed so that its long side direction intersects with the X direction and the Z direction (refer to Fig.11D A slit portion 42 may be formed in the plate-shaped shield portion 41 of the magnetic shield 4 (see Fig.11A , Fig. 11B and Fig.11D ), a plurality of slit portions 42 may be formed (see Fig. 11C The slit portion 42 may be formed so as to overlap with the magnetic detection portion 2 when viewed along the Y direction, that is, at least a portion of the magnetic detection portion 2 is exposed from the slit portion 42 (see Fig.11A , Fig. 11B and Fig.11D), it may also be formed so as not to overlap with the magnetic detection unit 2 (see Fig. 11C ).

[0096] In the first aspect of the current sensor 1 of the present embodiment, if the slit portion 42 is not formed in the plate-shaped shield portion 41 of the magnetic shield 4, the disturbance magnetic field H in the Y direction Y The magnetic shield 4 is transmitted in the thickness direction of the plate-shaped shielding portion 41 (see Fig. 12A ). Even if a disturbance magnetic field H in the Y direction is applied to the magnetic detection unit 2 having a sensitivity axis in the X direction, Y However, when the sensitivity axis of the magnetic detection unit 2 in the current sensor 1 is shifted from the X direction to the ±Y direction due to the installation error of the magnetic detection unit 2 or the like, the plate-shaped shielding unit 41 without the slit 42 will cause the disturbance magnetic field H in the Y direction to Y Since the plate-shaped shielding portion 41 is transparent in the thickness direction, the current sensor 1 may be affected by the disturbance magnetic field H. Y The impact produced.

[0097] On the other hand, by forming the slit portion 42 in the plate-shaped shield portion 41, the disturbance magnetic field H in the Y direction can be reduced. Y The magnetic field H is dispersed to both sides of the slit portion 42 (both sides in the short side direction of the slit portion 42 when viewed along the Y direction). Therefore, when the slit portion 42 is formed so as to overlap with the magnetic detection portion 2 when viewed along the Y direction, the disturbance magnetic field H directed toward the magnetic detection portion 2 along the Y direction can be suppressed. Y applied to the magnetic detection unit 2 (refer to Fig. 12B ).

[0098] Furthermore, when the slit portion 42 is formed so as not to overlap the magnetic detection unit 2 when viewed along the Y direction, it is difficult to suppress the disturbance magnetic field H directed toward the magnetic detection unit 2 along the Y direction. Y The magnetic field H is applied to the magnetic detection unit 2, but the disturbance magnetic field H that enters from the outside of the magnetic shield 4 and is guided to the magnetic shield 4 can be suppressed. Y Impact on current sensor 1 (see Fig. 12C ).

[0099] exist Fig.11A In the embodiment shown, the length L of the slit portion 42 in the longitudinal direction (X direction) is 42 The length L in the X direction of the core gap CG can be CG Short or long, or with this length L CG Same. Figures 11A to 11D In the embodiment shown, the length W of the slit portion 42 in the short side direction is 42 For example, it only needs to be about 1 to 4 mm, preferably about 2 to 3 mm. 42If the diameter is less than 1 mm, the interfering magnetic field H cannot be effectively dispersed by the slit portion 42. Y , interfering magnetic field H Y It is possible that the magnetic shield 41 of the plate-shaped shield 4 is passed through the thickness direction and applied to the magnetic detection unit 2. In addition, if the length W 42 If it exceeds 4 mm, the interfering magnetic field H in the Y direction Y There is a possibility that the magnetic field may pass through the slit portion 42 and be applied to the magnetic detection portion 2 .

[0100] According to the first aspect of the current sensor 1 of this embodiment, the magnetic shield 4 is provided so as to overlap the core gap CG of the magnetic core 2 when viewed from the Y direction, so that at least the disturbance magnetic field H in the X direction can be blocked. x The interference magnetic field H can be suppressed by guiding it to the magnetic collecting core 2 and the magnetic shield 4. x Therefore, according to the first aspect of the current sensor 1 of the present embodiment, the current flowing in the conductor 5 can be detected with high accuracy.

[0101] A second embodiment of the current sensor 1 of this embodiment will be described. In addition, the same symbols are given to the same structures as those in the first embodiment, and their detailed descriptions are omitted. Figures 13-16 As shown, the second embodiment of the current sensor 1 includes a magnetic detection unit 2 capable of detecting magnetism, a magnetic collecting core 3 , a magnetic shield 4 , and a conductor 5 through which a current flows in the Z direction.

[0102] The magnetic shield 4 includes a first shield portion 43 and a second shield portion 44 which are continuous with both ends 41A and 41B in the Z direction of the plate-shaped shield portion 41 and extend in the Y direction. The length L of the plate-shaped shield portion 41 in the X direction is 41 The length L of the first shield portion 43 in the X direction 43 The length in the X direction is the same as that of the second shield portion 44. That is, the magnetic shield 4 has a substantially U-shape when viewed along the X direction.

[0103] In the second aspect of the current sensor 1 of the present embodiment, the magnetic shield 4 includes a first shield portion 43 and a second shield portion 44 that are continuous with both ends 41A and 41B of the plate-shaped shield portion 41 in the Z direction. The first shield portion 43 and the second shield portion 44 extend from both ends 41A and 41B of the plate-shaped shield portion 41 in the -Y direction. Since the magnetic shield 4 includes the first shield portion 43 and the second shield portion 44, the disturbance magnetic field H in the Y direction is Y is guided to the first shield portion 43 and the second shield portion 44 (see Fig.17A ), therefore, the interfering magnetic field H can be suppressed Y is applied to the magnetic detection unit 2. In addition, the disturbance magnetic field H in the X direction x The magnetic flux is guided from the fourth core portion 34 or the fifth core portion 35 of the magnetic flux collecting core 3 to the first shield portion 43 and the second shield portion 44 (see Fig. 17B ), therefore, the interfering magnetic field H can be suppressed x Applied to the magnetic detection unit 2.

[0104] The length T of the first shield portion 43 and the second shield portion 44 in the Y direction 43 、T 44 There are no particular limitations as long as the length does not contact the conductor 5, but it is preferably longer than a length that completely overlaps the core gap CG when viewed along the Z direction (see Fig.16 ). When viewed along the Z direction, the first shield portion 43 and the second shield portion 44 completely overlap with the core gap CG, which can effectively suppress the interference magnetic field H in the X direction. x And the interfering magnetic field H in the Y direction Y are applied to the magnetic detection unit 2. The length T 43 、T 44 For example, it only needs to be about 6 to 10 mm. 43 and the length T in the Y direction of the second shield portion 44 44 They may be the same as or different from each other.

[0105] In this embodiment, both ends 41A and 41B of the plate-shaped shield 41 and the continuous portions of the first shield 43 and the second shield 44 have curved shapes (rounded corners), but the present invention is not limited to this form. For example, these continuous portions may have a zigzag shape (a shape with corners) or a C-chamfered shape with chamfered corners.

[0106] In the second aspect of the current sensor 1 of this embodiment, Figures 18A to 18D As shown in FIG. 1 , a slit portion 42 penetrating in the Y direction may be formed in the plate-shaped shield portion 41 of the magnetic shield 4. The slit portion 42 may be formed so that its long side direction is substantially parallel to the X direction (see FIG. 1 ). Fig.18A ), it can also be formed so that its long side direction is substantially parallel to the Z direction (refer to Fig.18B and Fig. 18C ), and can also be formed so that its long side direction intersects with the X direction and the Z direction (refer to Fig.18D A slit portion 42 may be formed in the plate-shaped shield portion 41 of the magnetic shield 4 (see Fig.18A , Fig.18B and Fig.18D ), a plurality of slit portions 42 may be formed (see Fig. 18C The slit portion 42 may be formed so as to overlap with the magnetic detection portion 2 when viewed along the Y direction, that is, at least a portion of the magnetic detection portion 2 is exposed from the slit portion 42 (see Fig.18A , Fig.18B and Fig.18D ), it may also be formed so as not to overlap with the magnetic detection unit 2 (see Fig. 18C ).

[0107] In the second aspect of the current sensor 1 of this embodiment, the disturbance magnetic field H in the Y direction Y It is easy to be guided to the first shield part 43 and the second shield part 44. However, if the slit part 42 is not formed in the plate-shaped shield part 41 of the magnetic shield 4, the disturbance magnetic field H in the Y direction Y A portion of the magnetic shield 4 will penetrate in the thickness direction of the plate-shaped shielding portion 41 (see Fig.17A As a result, the current sensor 1 may be affected by the disturbance magnetic field H Y The impact produced.

[0108] On the other hand, by forming the slit portion 42 in the plate-shaped shield portion 41, the disturbance magnetic field H in the Y direction can be reduced. Y The disturbance magnetic field H is dispersed toward both sides of the slit portion 42 (both sides in the short side direction (Z direction) of the slit portion 42 when viewed along the Y direction), and the disturbance magnetic field H is easily Y Therefore, when the slit portion 42 is formed so as to overlap the magnetic detection unit 2 when viewed along the Y direction, the disturbance magnetic field H directed toward the magnetic detection unit 2 along the Y direction can be effectively suppressed. Y applied to the magnetic detection unit 2 (refer to Fig.19 ).

[0109] Furthermore, when the slit portion 42 does not overlap the magnetic detection unit 2 when viewed along the Y direction, the disturbance magnetic field H that enters from the outside of the magnetic shield 4 and is guided to the magnetic shield 4 can be suppressed. Y Impact on current sensor 1 (see Fig. 12C ).

[0110] exist Fig.18A In the embodiment shown in the figure, the length L of the slit portion 42 in the longitudinal direction (X direction) is 42 The length L in the X direction of the core gap CG can be CG Short or long, or with this length L CG Same. Figures 18A to 18D In the embodiment shown, the length W of the slit portion 42 in the short side direction is 42 For example, it only needs to be about 1 to 4 mm, preferably about 2 to 3 mm. 42 If the interference magnetic field H generated by the slit portion 42 is less than 1 mm, Y The effect is reduced. The interfering magnetic field H that passes through the plate-shaped shielding portion 41 of the magnetic shield 4 in the thickness direction Y It may be applied to the magnetic detection unit 2. In addition, if the length W 42 If it exceeds 4 mm, the interfering magnetic field H in the Y direction YThere is a possibility that the magnetic field may be applied to the magnetic detection unit 2 through the slit portion 42 .

[0111] In the second aspect of the current sensor 1 of the present embodiment having the above-described structure, the magnetic shield 4 includes the first shield portion 43 and the second shield portion 44 which are continuous with both end portions 41A and 41B of the plate-shaped shield portion 41, so that the disturbance magnetic field H in the Y direction can be blocked. Y The interference magnetic field H in the X direction is guided to the first shield portion 43 and the second shield portion 44. x The magnetic field H is guided to the plate-shaped shielding portion 41 of the magnetic shield 4 and the magnetic collecting core 3. Therefore, according to the second aspect of the current sensor 1, it is possible to suppress the disturbance magnetic field H in the X direction. x And the interfering magnetic field H in the Y direction y This results in detection errors.

[0112] A third embodiment of the current sensor 1 of the present embodiment will be described. In addition, the same reference numerals are given to the same structures as those in the first and second embodiments, and their detailed descriptions are omitted. Figures 20-22 As shown, the third embodiment of the current sensor 1 includes a magnetic detection unit 2 capable of detecting magnetism, a magnetic collecting core 3 , a magnetic shield 4 , and a conductor 5 through which a current flows in the Z direction.

[0113] The magnetic core 3 includes: a first core portion 31; a second core portion 32 and a third core portion 33, which are continuous with both ends 31A and 31B of the first core portion 31; a fourth core portion 34, which is continuous with a predetermined position 321 of the second core portion 32 in the Y direction and extends along the X direction; and a fifth core portion 35, which is continuous with a predetermined position 331 of the third core portion 33 in the Y direction and extends along the X direction. The second core portion 32 further extends along the Y direction from the continuous portion 321 with the fourth core portion 34, and the third core portion 33 further extends along the Y direction from the continuous portion 331 with the fifth core portion 35. That is, the fourth core portion 34 is not continuous with the end portion 32A of the second core portion 32, and the fifth core portion 35 is not continuous with the end portion 33A of the third core portion 33. The fourth core portion 34 and the fifth core portion 35 extend along the X direction so that their end faces are close to each other. A gap (space) sandwiched between the end surface of the fourth core portion 34 and the end surface of the fifth core portion 35 is a core gap CG.

[0114] In the third aspect of the current sensor 1 of the present embodiment, the second core portion 32 extends from the continuous portion 321 of the second core portion 32 and the fourth core portion 34 along the Y direction, and the third core portion 33 extends from the continuous portion 331 of the third core portion 33 and the fifth core portion 35 along the Y direction, so that the interference magnetic field H in the X direction can be reduced. x The interfering magnetic field H can be suppressed by guiding it to the first core portion 31 side, the end portion 32A side of the second core portion 32, or the end portion 33A side of the third core portion 33. x The impact produced.

[0115] In the present embodiment, the end 31A of the first core portion 31 and the continuous portion of the second core portion 32, the end 31B of the first core portion 31 and the continuous portion of the third core portion 33, the continuous portion 321 of the second core portion 32 and the fourth core portion 34, and the continuous portion 331 of the third core portion 33 and the fifth core portion 35 of the magnetic core 3 all have a zigzag shape (a shape with an angle), but are not limited to this form. For example, these continuous portions can be a curved shape (rounded shape) or a C-chamfered shape with chamfered corners.

[0116] When the magnetic collecting core 3 is arranged so that the first core portion 31 is directed downward and the second core portion 32 and the third core portion 33 extend upward from the two ends 31A and 31B of the first core portion 31, the plate-shaped shield portion 41 of the magnetic shield 4 is arranged above the fourth core portion 34 and the fifth core portion 35 and sandwiched between the second core portion 32 and the third core portion 33 in the X direction. In the third embodiment of the current sensor 1 having such a structure, the length T of the second core portion 32 from the continuous portion 321 of the fourth core portion 34 to the end portion 32A along the Y direction is 322 and the length T of the third core portion 33 from the continuous portion 331 of the fifth core portion 35 to the end portion 33A along the Y direction 332 There is no particular limitation. For example, the length T 322 、T 332 The length T may be such that the end 32A of the second core 32 and the end 33A of the third core 33 protrude upward from the plate-shaped shield 41, or such that the plate-shaped shield 41 protrudes upward from the end 32A of the second core 32 and the end 33A of the third core 33. 322 、T 332 The length may be such that the upper surface of the plate-shaped shield portion 41 and the both end portions 32A and 33A are located on the same plane (XZ plane).

[0117] The length G of the gap in the Y direction between the magnetic shield 4 (plate-shaped shield portion 41) and the magnetic collecting core 3 (fourth core portion 34 and fifth core portion 35) is 34 For example, it may be less than 3 mm, or may be about 1 to 2 mm. 34 If it exceeds 3mm, the interference magnetic field H in the Y direction Y It is possible that the magnetic shield 4 is wound from the outside of the end surface in the Z direction toward the magnetic detector 2 and applied to the magnetic detector 2. In addition, if the length G of the gap is 34 If it is relatively short (for example, less than 1 mm), a magnetic path is formed from the magnetic core 3 through the magnetic shield 4, and the magnetic flux easily flows to the magnetic shield 4. Therefore, the magnetic core 3 is easily magnetically saturated, and the magnetic flux to be detected by the magnetic detection unit 2 may be reduced.

[0118] In this embodiment, the magnetic shield 4 is arranged such that the plate-shaped shield portion 41 completely overlaps the core gap CG when viewed in the Y direction. That is, the length L of the plate-shaped shield portion 41 of the magnetic shield 4 in the X direction is 41 and the length W in the Z direction 41 As long as the length L of the core gap CG in the X direction CG and the length in the Z direction, that is, the width W of the magnetic core 3 in the Z direction. 3 For example, the length L of the plate-shaped shielding portion 41 in the X direction is 41 As long as the length L of the core gap CG in the X direction CG +4mm or more, the length L of the magnetic core 3 in the X direction 3 The following degree is sufficient, the length W in the Z direction 41 As long as the width W of the magnetic core 3 in the Z direction 3 As described above, the width W of the magnetic core 3 in the Z direction is 3 The third aspect of the current sensor 1 of this embodiment is not limited to this aspect. For example, as long as the magnetic shield 4 can suppress the disturbance magnetic field H in the Y direction, Y In the case of the magnetic detection unit 2 , the plate-shaped shield 41 may not completely overlap the core gap CG.

[0119] In the third aspect of the current sensor 1 of this embodiment, Figures 23A to 23D As shown in FIG. 1 , a slit portion 42 penetrating in the Y direction may be formed in the plate-shaped shield portion 41 of the magnetic shield 4. The slit portion 42 may be formed so that its long side direction is substantially parallel to the X direction (see FIG. 1 ). Fig.23A ), it can also be formed so that its long side direction is substantially parallel to the Z direction (refer to Fig. 23B and Fig.23C ), and can also be formed so that its long side direction intersects with the X direction and the Z direction (refer to Fig.23D A slit portion 42 may be formed in the plate-shaped shield portion 41 of the magnetic shield 4 (see Fig.23A , Fig. 23B and Fig.23D ), a plurality of slit portions 42 may be formed (see Fig.23C The slit portion 42 may be formed so as to overlap with the magnetic detection portion 2 when viewed along the Y direction, that is, at least a portion of the magnetic detection portion 2 is exposed from the slit portion 42 (see Fig.23A , Fig. 23B and Fig.23D ), it may also be formed so as not to overlap with the magnetic detection unit 2 (see Fig.23C ).

[0120] In the third aspect of the current sensor 1 of the present embodiment, when the slit portion 42 is not formed in the plate-shaped shield portion 41 of the magnetic shield 4, the disturbance magnetic field H in the Y directionY A portion of the magnetic shield 4 will penetrate in the thickness direction of the plate-shaped shielding portion 41 (see Fig. 12A As a result, the current sensor 1 may be affected by the disturbance magnetic field H Y The impact produced.

[0121] On the other hand, by forming the slit portion 42 in the plate-shaped shield portion 41, the disturbance magnetic field H in the Y direction can be reduced. Y The magnetic field H is dispersed to both sides of the slit portion 42 (both sides in the short side direction (Z direction) of the slit portion 42 when viewed along the Y direction). Therefore, when the slit portion 42 is formed so as to overlap with the magnetic detection portion 2 when viewed along the Y direction, the disturbance magnetic field H directed toward the magnetic detection portion 2 along the Y direction can be effectively suppressed. Y applied to the magnetic detection unit 2 (refer to Fig. 12B 〉.

[0122] Furthermore, when the slit portion 42 is formed so as not to overlap the magnetic detection unit 2 when viewed along the Y direction, the disturbance magnetic field H that enters from the outside of the magnetic shield 4 and is guided to the magnetic shield 4 can be suppressed. Y Impact on current sensor 1 (see Fig. 12C ).

[0123] exist Fig.23A In the embodiment shown, the length L of the slit portion 42 in the longitudinal direction (X direction) is 42 The length L in the X direction of the core gap CG can be CG Short or long, or with this length L CG Same. Figures 23A to 23D In the embodiment shown, the length W of the slit portion 42 in the short side direction is 42 For example, it only needs to be about 1 to 4 mm, preferably about 2 to 3 mm. 42 If the interfering magnetic field H generated by the slit portion 42 is less than 1 mm, Y The dispersion effect is reduced, and the disturbance magnetic field H that passes through the plate-shaped shielding portion 41 of the magnetic shield 4 in the thickness direction is Y It is possible to apply to the magnetic detection unit 2. In addition, if the length W 42 If it exceeds 4 mm, the interfering magnetic field H in the Y direction Y There is a possibility that the magnetic field may be applied to the magnetism detecting portion 2 through the slit portion 42 .

[0124] According to the third aspect of the current sensor 1 having the above-mentioned structure, it is possible to suppress the current sensor 1 from receiving the disturbance magnetic field H in the X direction. x And the interfering magnetic field H in the Y direction Y Therefore, the current flowing in the conductor 5 can be detected with high accuracy.

[0125] A fourth aspect of the current sensor 1 of the present embodiment will be described. In addition, the same reference numerals are given to the same structures as those in the first to third aspects, and their detailed descriptions are omitted. Figures 24-26 As shown, the fourth embodiment of the current sensor 1 includes a magnetic detection unit 2 capable of detecting magnetism, a magnetic collecting core 3 , a magnetic shield 4 , and a conductor 5 through which a current flows in the Z direction.

[0126] The magnetic collecting core 3 has a first core portion 31 substantially parallel to the Z direction, a second core portion 32 and a third core portion 33 which are continuous with both ends 31A and 31B of the first core portion 31 in the X direction and extend in the Y direction (+Y direction). A gap (space) sandwiched between the vicinity of the end of the second core portion 32 and the vicinity of the end of the third core portion 33 which are opposite to each other in the X direction is a core gap CG. That is, the magnetic collecting core 3 has a core gap CG and is a substantially U-shaped core when viewed along the Z direction. In the fourth embodiment, the magnetic flux generated from the conductor 5 and gathered in the magnetic collecting core 3 comes out from the end of the second core portion 32 or the end of the third core portion 33 and is absorbed by the end of the third core portion 33 or the end of the second core portion 32, but "the vicinity of the end of the second core portion 32" and "the vicinity of the end of the third core portion 33" can be defined as a region where the above-mentioned magnetic flux is generated at the end of the second core portion 32 and the end of the third core portion 33, and a region where the above-mentioned magnetic flux is absorbed at the end of the second core portion 32 and the end of the third core portion 33. The region where the magnetic flux is generated or absorbed can be determined by, for example, magnetic simulation or the like.

[0127] The length L of the core gap CG in the X direction CG (The distance in the X direction between the vicinity of the end of the second core portion 32 and the vicinity of the end of the third core portion 33) may be, for example, 6 mm or more, or may be about 6 to 12 mm. CG When the thickness is 6 mm or more, the effect of the current sensor 1 of the present embodiment having the magnetic shield 4 , that is, the effect of suppressing the application of a disturbance magnetic field to the magnetic detection unit 2 by the magnetic shield 4 can be effectively achieved.

[0128] The magnetic shield 4 includes a first shield portion 43 and a second shield portion 44 that are continuous with both ends 41A and 41B of the plate-shaped shield portion 41 in the Z direction and extend in the Y direction. The length L of the plate-shaped shield portion 41 in the X direction is 41 The length L of the first shield portion 43 in the X direction 43 The length in the X direction is the same as that of the second shield portion 44. That is, the magnetic shield 4 has a substantially U-shape when viewed along the X direction.

[0129] In the fourth aspect of the current sensor 1 of the present embodiment, the magnetic shield 4 includes a first shield portion 43 and a second shield portion 44 that are continuous with both ends 41A and 41B of the plate-shaped shield portion 41 in the Z direction. The first shield portion 43 and the second shield portion 44 extend from both ends 41A and 41B of the plate-shaped shield portion 41 in the -Y direction. Since the magnetic shield 4 includes the first shield portion 43 and the second shield portion 44, the disturbance magnetic field H in the Y direction is Y is guided to the first shield portion 43 and the second shield portion 44 (see Fig.17A ), therefore, the interfering magnetic field H can be suppressed Y is applied to the magnetic detection unit 2. In addition, the disturbance magnetic field H in the X direction x The fourth core portion 34 or the fifth core portion 35 of the magnetic collecting core 3 is guided to the first shield portion 43 and the second shield portion 44 (see Fig. 17B ), therefore, the interfering magnetic field H can be suppressed x Applied to the magnetic detection unit 2.

[0130] The first shield portion 43 and the second shield portion 44 have recessed portions 45 and 46 substantially at their centers in the X direction and recessed toward the +Y direction. The length L of the recessed portions 45 and 46 in the X direction is 45 , L 46 There is no particular limitation, but it only needs to be greater than the thickness of the conductor 5. In the fourth aspect of the current sensor 1, the conductor 5 is provided so that the thickness direction is the X direction and it extends in the Z direction. By arranging a part of the conductor 5 in the recesses 45 and 46, it is possible to suppress the disturbance magnetic field H in the Y direction by the first shield portion 43 and the second shield portion 44 without increasing the overall size of the current sensor 1. Y Effect applied to the magnetic detection unit 2.

[0131] The conductor 5 is arranged so that its thickness direction is the X direction and its width direction is the Y direction, and it extends in the Z direction. By arranging the conductor 5 in this way, the size of the current sensor 1 in the X direction can be made compact. On the other hand, if the conductor 5 is arranged in this way, the size of the current sensor 1 in the Y direction will increase, but by providing the recesses 45 and 46 in the first shield portion 43 and the second shield portion 44 and arranging a part of the conductor 5 in the recesses 45 and 46, the size of the current sensor 1 in the Y direction can be prevented from increasing.

[0132] In the fourth aspect of the current sensor 1 of this embodiment, Figures 27A to 27D As shown in FIG. 1 , a slit portion 42 penetrating in the Y direction may be formed in the plate-shaped shield portion 41 of the magnetic shield 4. The slit portion 42 may be formed so that its long side direction is substantially parallel to the X direction (see FIG. 1 ). Fig.27A ), it can also be formed so that its long side direction is substantially parallel to the Z direction (refer to Fig.27Band Fig.27C ), and can also be formed so that its long side direction intersects with the X direction and the Z direction (refer to Fig.27D A slit portion 42 may be formed in the plate-shaped shield portion 41 of the magnetic shield 4 (see Fig.27A , Fig.27B and Fig.27D ), a plurality of slit portions 42 may be formed (see Fig.27C The slit portion 42 may be formed so as to overlap with the magnetic detection portion 2 when viewed along the Y direction, that is, at least a portion of the magnetic detection portion 2 is exposed from the slit portion 42 (see Fig.27A , Fig.27B and Fig.27D ), it may also be formed so as not to overlap with the magnetic detection unit 2 (see Fig.27C ).

[0133] In the fourth aspect of the current sensor 1 of the present embodiment, if the slit portion 42 is not formed in the plate-shaped shield portion 41 of the magnetic shield 4, the disturbance magnetic field H in the Y direction Y A portion of the magnetic shield 4 will penetrate along the thickness direction of the plate-shaped shielding portion 41 (see Fig.17A As a result, the current sensor 1 may be affected by the disturbance magnetic field H Y The impact produced.

[0134] On the other hand, by forming the slit portion 42 in the plate-shaped shield portion 41, the disturbance magnetic field H in the Y direction can be reduced. Y The magnetic field H is dispersed to both sides of the slit portion 42 (both sides in the short side direction (Z direction) of the slit portion 42 when viewed along the Y direction). Therefore, when the slit portion 42 is formed so as to overlap with the magnetic detection portion 2 when viewed along the Y direction, the disturbance magnetic field H directed toward the magnetic detection portion 2 along the Y direction can be effectively suppressed. Y applied to the magnetic detection unit 2 (refer to Fig.19 ).

[0135] Furthermore, when the slit portion 42 is formed so as not to overlap the magnetic detector 2 when viewed along the Y direction, the disturbance magnetic field H that enters from the outside of the magnetic shield 4 and is guided to the magnetic shield 4 can be suppressed. Y Impact on current sensor 1 (see Fig. 12C ).

[0136] exist Fig.27A In the embodiment shown, the length L of the slit portion 42 in the longitudinal direction (X direction) is 42 The length L in the X direction of the core gap CG can be CG Short or long, or with this length L CG Same. Figures 27A to 27D In the embodiment shown, the length W of the slit portion 42 in the short side direction is 42For example, it only needs to be about 1 to 4 mm, preferably about 2 to 3 mm. 42 If the interference magnetic field H generated by the slit portion 42 is less than 1 mm, Y The effect of the magnetic shield 4 is reduced, and the interfering magnetic field H that penetrates the plate-shaped shielding portion 41 of the magnetic shield 4 in the thickness direction y will be applied to the magnetic detection unit 2. In addition, if the length W 42 If it exceeds 4 mm, the interfering magnetic field H in the Y direction Y There is a possibility that the magnetic field may pass through the slit portion 42 and be applied to the magnetic detection portion 2 .

[0137] According to the fourth aspect of the current sensor 1 having the above-mentioned structure, it is possible to suppress the current sensor 1 from receiving the disturbance magnetic field H in the X direction. x And the interfering magnetic field H in the Y direction Y Therefore, the current flowing in the conductor 5 can be detected with high accuracy.

[0138] A fifth aspect of the current sensor 1 of the present embodiment will be described. In addition, the same reference numerals are given to the same structures as those of the first to fourth aspects, and their detailed descriptions are omitted. Figures 28-30 As shown, the fifth embodiment of the current sensor 1 includes a magnetic detection unit 2 capable of detecting magnetism, a magnetic collecting core 3 , a magnetic shield 4 , and a conductor 5 through which a current flows in the Z direction.

[0139] In the fifth aspect of the current sensor 1 of the present embodiment, the magnetic shield 4 includes a first shield portion 43 and a second shield portion 44 that are continuous with both ends 41A and 41B of the plate-shaped shield portion 41 in the Z direction. The first shield portion 43 and the second shield portion 44 extend from both ends 41A and 41B of the plate-shaped shield portion 41 in the -Y direction. Since the magnetic shield 4 includes the first shield portion 43 and the second shield portion 44, the disturbance magnetic field H in the Y direction is Y is guided to the first shield portion 43 and the second shield portion 44 (see Fig.17A ), which can suppress the interfering magnetic field H Y is applied to the magnetic detection unit 2. In addition, the disturbance magnetic field H in the X direction X The fourth core portion 34 or the fifth core portion 35 of the magnetic collecting core 3 is guided to the first shield portion 43 and the second shield portion 44 (see Fig. 17B ), therefore, the interfering magnetic field H can be suppressed X Applied to the magnetic detection unit 2.

[0140] The length L of the plate-shaped shielding portion 41 in the X direction is 41 The length L of the first shield portion 43 in the X direction is 43 The length L of the second shield portion 44 in the X direction is longer. 43The length of the second shield portion 44 in the X direction may be equal to the length L of the core gap CG in the X direction. CG The same length L CG Longer, or shorter.

[0141] In the fifth aspect of the current sensor 1 of this embodiment, Figures 31A to 31D As shown in FIG. 1 , a slit portion 42 penetrating in the Y direction may be formed in the plate-shaped shield portion 41 of the magnetic shield 4. The slit portion 42 may be formed so that its long side direction is substantially parallel to the X direction (see FIG. 1 ). Fig.31A ), it can also be formed so that its long side direction is substantially parallel to the Z direction (refer to Fig.31B and Fig.31C ), and can also be formed so that its long side direction intersects with the X direction and the Z direction (refer to Fig.31D A slit portion 42 may be formed in the plate-shaped shield portion 41 of the magnetic shield 4 (see Fig.31A , Fig.31B and Fig.31D ), a plurality of slit portions 42 may be formed (see Fig.31C The slit portion 42 may be formed so as to overlap with the magnetic detection portion 2 when viewed along the Y direction, that is, at least a portion of the magnetic detection portion 2 is exposed from the slit portion 42 (see FIGS. 31, Fig.31B and Fig.31D ), it may also be formed so as not to overlap with the magnetic detection unit 2 (see Fig.31C ).

[0142] In the fifth aspect of the current sensor 1 of the present embodiment, if the slit portion 42 is not formed in the plate-shaped shield portion 41 of the magnetic shield 4, the disturbance magnetic field H in the Y direction Y A portion of the magnetic shield 4 will penetrate along the thickness direction of the plate-shaped shielding portion 41 (see Fig.17A As a result, the current sensor 1 may be affected by the disturbance magnetic field H Y The impact produced.

[0143] On the other hand, by forming the slit portion 42 in the plate-shaped shield portion 41, the disturbance magnetic field H in the Y direction can be reduced. Y The magnetic field H is dispersed to both sides of the slit portion 42 (both sides in the short side direction (Z direction) of the slit portion 42 when viewed along the Y direction). Therefore, when the slit portion 42 is formed so as to overlap with the magnetic detection portion 2 when viewed along the Y direction, the disturbance magnetic field H directed toward the magnetic detection portion 2 along the Y direction can be effectively suppressed. Y applied to the magnetic detection unit 2 (refer to Fig.19 ).

[0144] Furthermore, when the slit portion 42 is formed so as not to overlap the magnetic detection unit 2 when viewed along the Y direction, the disturbance magnetic field H that enters from the outside of the magnetic shield 4 and is guided to the magnetic shield 4 can be suppressed. Y Impact on current sensor 1 (see Fig. 12C ).

[0145] exist Fig.31A In the embodiment shown, the length L of the slit portion 42 in the longitudinal direction (X direction) is 42 The length L in the X direction of the core gap CG can be CG Short or long, or with this length L CG Same. Figures 31A to 31D In the embodiment shown, the length W of the slit portion 42 in the short side direction is 42 For example, it only needs to be about 1 to 4 mm, preferably about 2 to 3 mm. 42 If the interference magnetic field H generated by the slit portion 42 is less than 1 mm, Y The effect of the magnetic shield 4 is reduced, and the interfering magnetic field H that penetrates the plate-shaped shielding portion 41 of the magnetic shield 4 in the thickness direction Y It is possible to apply to the magnetic detection unit 2. In addition, if the length W 42 If it exceeds 4 mm, the interfering magnetic field H in the Y direction Y There is a possibility that the magnetic field may pass through the slit portion 42 and be applied to the magnetic detection portion 2 .

[0146] According to the fifth aspect of the current sensor 1 having the above-mentioned structure, it is possible to suppress the current sensor 1 from receiving the disturbance magnetic field H in the X direction. X And the interfering magnetic field H in the Y direction Y Therefore, the current flowing in the conductor 5 can be detected with high accuracy.

[0147] The electrical control device may include the current sensor 1 of the present embodiment having the above-mentioned structure. In addition, as the electrical control device in the present embodiment, for example, a battery management system, an inverter, and a converter of a hybrid electric vehicle (HEV) or an electric vehicle (EV) are cited. The current sensor 1 of the present embodiment is used to measure the input and output currents from the power supply, and output information related to the measured current to the electrical control device.

[0148] The embodiments described above are described to facilitate understanding of the present invention, and are not described to limit the present invention. Therefore, the elements disclosed in the above embodiments are intended to include all design changes and equivalents within the technical scope of the present invention.

[0149] In the third aspect of the current sensor 1 of the above-mentioned embodiment (see Fig. 20 In the embodiment of the present invention, the magnetic shield 4 may include a first shield portion and a second shield portion which are continuous with both ends of the plate-shaped shield portion 41 in the Z direction and extend along the Y direction.

[0150] Example

[0151] Hereinafter, the present invention will be described in more detail with reference to test examples, but the present invention is not limited to the following test examples.

[0152] [Test Example 1]

[0153] In having Figure 1 In the current sensor 1 having the structure shown in the figure, the disturbance magnetic field H in the X direction is obtained by simulation. X The output signal from the current sensor 1 when OmT (miltesla) is set and the disturbance magnetic field H in the X direction is set X The output signal from the current sensor 1 is set to 10mT, and the disturbance magnetic field H in the X direction is calculated. X The error (EX, %) of the output signal of the current sensor 1 generated by the simulation is similarly obtained by changing the Y-direction disturbance magnetic field H to X The output signal from the current sensor 1 when OmT (miltesla) is set and the disturbance magnetic field H in the Y direction is set X The output signal from the current sensor 1 is set to 10mT, and the disturbance magnetic field H in the Y direction is calculated. Y The simulation results are shown in Table 1.

[0154] [Test Example 2]

[0155] Except for using Fig.11A In addition to the current sensor 1 having the structure shown in the figure, the disturbance magnetic field H in the X direction is calculated in the same manner as in the above-mentioned Experimental Example 1. X The error (EX, %) of the output signal of the current sensor 1 and the interference magnetic field H in the Y direction Y The simulation results are shown in Table 1.

[0156] [Test Example 3]

[0157] Except for using Fig.23A In addition to the current sensor 1 having the structure shown in the figure, the disturbance magnetic field H in the X direction is calculated in the same manner as in the above-mentioned Experimental Example 1. X The error (EX, %) of the output signal of the current sensor 1 and the interference magnetic field H in the Y directionY The simulation results are shown in Table 1.

[0158] [Test Example 4]

[0159] Except for using Fig.13 In addition to the current sensor 1 having the structure shown in the figure, the disturbance magnetic field H in the X direction is calculated in the same manner as in the above-mentioned Experimental Example 1. X The error (EX, %) of the output signal of the current sensor 1 and the interference magnetic field H in the Y direction Y The simulation results are shown in Table 1.

[0160] [Test Example 5]

[0161] Except for using Fig.18A In addition to the current sensor 1 having the structure shown in the figure, the disturbance magnetic field H in the X direction is calculated in the same manner as in the above-mentioned Experimental Example 1. X The error (EX, %) of the output signal of the current sensor 1 and the interference magnetic field H in the Y direction Y The simulation results are shown in Table 1.

[0162] [Test Example 6]

[0163] Except for using Fig.18B In addition to the current sensor 1 having the structure shown in the figure, the disturbance magnetic field H in the X direction is calculated in the same manner as in the above-mentioned Experimental Example 1. X The error (EX, %) of the output signal of the current sensor 1 and the interference magnetic field H in the Y direction Y The simulation results are shown in Table 1.

[0164] [Test Example 7]

[0165] Except for using Fig. 18C In addition to the current sensor 1 having the structure shown in the figure, the disturbance magnetic field H in the X direction is calculated in the same manner as in the above-mentioned Experimental Example 1. X The error (EX, %) of the output signal of the current sensor 1 and the interference magnetic field H in the Y direction Y The simulation results are shown in Table 1.

[0166] [Test Example 8]

[0167] Except for using Fig.24 In addition to the current sensor 1 having the structure shown in the figure, the disturbance magnetic field H in the X direction is calculated in the same manner as in the above-mentioned Experimental Example 1. X The error (EX, %) of the output signal of the current sensor 1 and the interference magnetic field H in the Y direction Y The simulation results are shown in Table 1.

[0168] [Test Example 9]

[0169] Except for using Fig.28 In addition to the current sensor 1 having the structure shown in the figure, the disturbance magnetic field H in the X direction is calculated in the same manner as in the above-mentioned Experimental Example 1. X The error (EX, %) of the output signal of the current sensor 1 and the interference magnetic field H in the Y direction are generated. Y The simulation results are shown in Table 1.

[0170] [Test Example 10]

[0171] A current sensor having the same structure as that of the above-mentioned Experimental Example 1 was used except that the magnetic shield 4 was not provided. The disturbance magnetic field H due to the X direction was calculated in the same manner as that of the above-mentioned Experimental Example 1. X The error (EX, %) of the output signal of the current sensor 1 and the interference magnetic field H in the Y direction Y The simulation results are shown in Table 1.

[0172] Table 1

[0173] EX(%) EY(%) Sample 1 1.89 1.96 Sample 2 1.24 1.45 Sample 3 1.24 1.45 Sample 4 0.90 1.45 Sample 5 0.97 1.43 Sample6 0.93 1.41 Sample 7 0.88 1.41 Sample 8 0.72 1.50 Sample 9 1.08 1.64 Sample 10 4.66 1.67

[0174] From the results shown in Table 1, it can be seen that, in the test examples 1 to 9 (Samples 1-9) using the current sensor 1 with the magnetic shield 4, the disturbance magnetic field H in the X direction can be reduced by at least 1:1. X This generates an error in the output signal of the current sensor 1.

[0175] In addition, the results of Sample 1, Sample 2, and Sample 3 show that the interference magnetic field H in the X direction can be reduced by forming the slit portion 42 in the plate-shaped shield portion 41 of the magnetic shield 4. X And the interfering magnetic field H in the Y direction Y This generates an error in the output signal of the current sensor 1.

[0176] Furthermore, from the results of Sample 1 and Sample 4, it can be seen that the magnetic shield 4 has a plate-shaped shield portion 41 and a first shield portion 43 and a second shield portion 44 that are continuous with the two ends 41A and 41B in the Z direction, thereby reducing the interference magnetic field H in the X direction. X And the interfering magnetic field H in the Y direction Y This generates an error in the output signal of the current sensor 1.

[0177] [Test Example 11]

[0178] In having Fig.13 In the current sensor 1 (Sample 11) of the structure shown in FIG. 1 , which uses silicon steel (50H230, manufactured by Nippon Steel Corporation, iron loss = 2.3 W / kg) as the constituent material of the magnetic core 3 and the magnetic shield 4, the attenuation (dB) of the magnetic flux density applied to the magnetic detection element 2 when the frequency of the alternating current flowing in the conductor 5 is changed within the range of 1 Hz to 100 kHz is obtained by simulation. The results are shown in FIG. Fig.32 .

[0179] [Test Example 12]

[0180] In a current sensor 1 (Sample 12) having the same structure as the current sensor 1 (Sample 11) of Test Example 11 except that silicon steel (50H470, manufactured by Nippon Steel Corporation, iron loss: 4.7 W / kg) is used as the constituent material of the magnetic shield 4, the attenuation (dB) of the magnetic flux density applied to the magnetic detection element 2 when the frequency of the alternating current flowing in the conductor 5 is varied within the range of 1 Hz to 100 kHz is obtained by simulation. The results are shown in Fig.32 .

[0181] [Test Example 13]

[0182] In a current sensor 1 (Sample 13) having the same structure as the current sensor 1 (Sample 11) of Test Example 11 except that silicon steel (50H700, manufactured by Nippon Steel Corporation, iron loss: 7.0 W / kg) is used as the constituent material of the magnetic shield 4, the attenuation (dB) of the magnetic flux density applied to the magnetic detection element 2 when the frequency of the alternating current flowing in the conductor 5 is varied within the range of 1 Hz to 100 kHz is obtained by simulation. The results are shown in Fig.32 .

[0183] [Test Example 14]

[0184] In a current sensor 1 (Sample 14) having the same structure as the current sensor 1 (Sample 11) of Test Example 11, except that silicon steel (50H1000, manufactured by Nippon Steel Corporation, iron loss: 10.0 W / kg) is used as the constituent material of the magnetic shield 4, the attenuation (dB) of the magnetic flux density applied to the magnetic detection element 2 when the frequency of the alternating current flowing in the conductor 5 is varied within the range of 1 Hz to 100 kHz is obtained by simulation. The results are shown in Fig.32 .

[0185] like Fig.32 As shown, it can be seen that the frequency characteristics of the current sensor 1 can be improved by making the core 3 of a material having a smaller iron loss than the magnetic shield 4. Therefore, by making the core 3 of a material having a smaller iron loss than the magnetic shield 4, the output of the current sensor 1 can be stabilized even when an alternating current flows in the conductor 5.

[0186] Explanation of symbols

[0187] 1…Current sensor

[0188] 2…Magnetic detection unit

[0189] 3…Collect magnetic core

[0190] 4…Magnetic shielding

[0191] 5…Conductor

Claims

1. A current sensor, characterized in that: is a current sensor for detecting magnetism generated by a conductor in which current flows in a first direction, A magnetic detection unit capable of detecting the magnetism, a magnetic collecting core, and a magnetic shield are provided. The magnetic collecting core includes: a first core portion substantially parallel to the first direction; a second core portion and a third core portion, which are respectively continuous with both ends of the first core portion in a second direction orthogonal to the first direction. The second core portion and the third core portion extend from ends of the first core portion along a third direction orthogonal to the first direction and the second direction, respectively. The magnetic detection portion has a magnetically sensitive direction in the second direction, and is located in a core gap sandwiched between the vicinity of an end of the second core portion and the vicinity of an end of the third core portion in the third direction. The magnetic shield includes a plate-shaped shielding portion positioned in a manner overlapping with the core gap, near the end of the second core portion, and near the end of the third core portion when viewed along the third direction, and the magnetic shield is not located: on the opposite side of the magnetic detection portion of the first core portion along the third direction when viewed along the first direction, on the opposite side of the third core portion of the second core portion along the second direction, and on the opposite side of the second core portion of the third core portion along the second direction.

2. The current sensor according to claim 1, characterized in that: The magnetic collecting core further includes a fourth core portion continuous to the vicinity of an end portion of the second core portion and a fifth core portion continuous to the vicinity of an end portion of the third core portion. The fourth core portion and the fifth core portion extend along the second direction so as to approach each other.

3. The current sensor according to claim 1 or 2, characterized in that: The conductor is a plate-like body extending along the first direction with the thickness direction being the third direction.

4. The current sensor according to claim 1, characterized in that: The conductor is a plate-like body extending along the first direction with the thickness direction being the second direction.

5. The current sensor according to claim 1 or 2, characterized in that: The magnetic shield includes a first shield portion and a second shield portion which are respectively continuous with both ends of the plate-shaped shield portion along the first direction and extend along the third direction. When viewed along the first direction, the magnetic detection portion is located in the core gap sandwiched by the first shield portion and the second shield portion.

6. The current sensor according to claim 1 or 2, characterized in that: The plate-shaped shield portion is formed with a slit portion penetrating in the third direction.

7. The current sensor according to claim 6, characterized in that: When viewed along the third direction, the long side direction of the slit portion is substantially consistent with the first direction.

8. The current sensor according to claim 6, characterized in that: When viewed along the third direction, the long side direction of the slit portion is substantially consistent with the second direction.

9. The current sensor according to claim 6, characterized in that: A plurality of the slit portions are formed in the plate-shaped shield portion.

10. The current sensor according to claim 1 or 2, characterized in that: The iron loss of the constituent material of the magnetic shield is greater than the iron loss of the constituent material of the magnetic collecting core.

11. The current sensor according to claim 1 or 2, characterized in that: The magnetic detection unit includes a magnetoresistive element or a Hall element.

12. The current sensor according to claim 11, characterized in that: The magnetoresistance effect element is a GMR element or a TMR element.

13. The current sensor according to claim 1 or 2, characterized in that: The conductor is provided so as to penetrate a space formed by the first core portion, the second core portion, and the third core portion of the magnetic flux collecting core along the first direction.

14. An electrical control device, characterized in that: A current sensor according to claim 13 is provided.

Images