CURRENT SENSOR AND CURRENT CONTROL SYSTEM

Abstract

A current sensor 10 capable of discharging air heated by heat generated from bus bars from a storage space to the outside in order to suppress a temperature rise around electronic components such as magnetic detectors, and suitable for measuring a large current in the present invention, comprises bus bars 11 through which a current to be measured flows, magnetic detectors 14 capable of detecting a magnetic field generated when the current to be measured flows through the bus bars 11, a storage space 13 in which the magnetic detectors 14 are housed, and a casing 12 with which a part of the bus bars 11 is integrally formed.Ends 11a of the busbars 11 are connected to an external first unit 20 including a cooling device 21, and other ends 11b of the busbars 11 are connected to an external second unit 30, whose temperature becomes higher than that of the first unit 20 when the current to be measured flows. In the current sensor 10 capable of measuring a current value of the current to be measured from a result of detection performed by the magnetic detectors 14, the housing 12 has first ventilation holes 15A penetrating from the inside of the storage space 13 to the outside on a side facing the first unit 20.

Description

Technical area

[0001] The present invention relates to a current sensor that detects a magnetic field generated by a current to be measured flowing through busbars and that measures a current value of the current to be measured from the detected magnetic field. background

[0002] In recent years, the increasing demand for decarbonization has led to a shift from internal combustion engines to electric motors, i.e. a move away from gasoline vehicles and a switch to electric propulsion (EV switch) in order to reduce CO 2 To reduce emissions from automobile driving. Current sensors (e.g., PTL 1) are used as current measuring devices that measure currents supplied to three-phase motors.

[0003] As the EV transition spreads to large commercial vehicles such as trucks and buses, motor power in hybrid and electric vehicles is increasing, as are the currents measured by current sensors used to control the motor. Motors are increasingly operated continuously under high load conditions, and the continuously flowing currents are increasing. Busbars, which are the current paths of the currents to be measured, generate heat at a rate proportional to the square of the current magnitude. Therefore, as the continuously flowing currents to be measured become larger, the amount of heat generated by the busbars increases, causing the temperature of electronic components such as magnetic detectors located near the busbars to rise. Citation listPatenliteratur

[0004] PTL 1: Japanese Patent No. 6462850 Summary of the inventionTechnical problem

[0005] Since a current sensor described in PTL 1 comprises a substrate containing electronic components in a storage space enclosed by a housing, it is difficult to dissipate the heat generated by the bus bars to the outside of the storage space. Therefore, the amount of heat generated by the bus bars increases, and the temperature in the storage space may exceed the heat-resistant temperature of magnetic detectors, thereby reducing the measurement accuracy of the current sensor or shortening the product lifespan.

[0006] The present invention therefore aims to provide a current sensor which is capable of discharging heated air from a storage space to the outside by means of heat generated by bus bars in order to suppress a temperature rise in the vicinity of electronic components such as magnetic detectors, and which is suitable for measuring a large current. Solution to the problem

[0007] The present invention includes the following configurations as a means for solving the above-described problem.

[0008] A current sensor includes a bus bar through which a current to be measured flows, a magnetic detector capable of detecting a magnetic field generated when the current to be measured flows through the bus bar, and a housing having a storage space in which the magnetic detector is housed and with which a part of the bus bar is integral. The current sensor is capable of measuring a current value of the current to be measured from the magnetic field detected by the magnetic detector. One end of the bus bar is connected to an external first unit including a cooling device, and another end of the bus bar is connected to an external second unit whose temperature is higher than the temperature of the first unit.The housing has a first vent penetrating from an inside of the storage space to an outside on a side facing the first unit.

[0009] Since the first vent is provided in a portion of the case facing the first unit, the airflow is caused by a difference in temperature between the bus bar and the first unit when the bus bar generates heat, and the air in the case heated by the heat generated by the bus bar is discharged to the outside of the storage space, thereby suppressing a rise in temperature in the case.

[0010] In addition to the first vent, the housing may have a second vent leading from the interior of the storage space to the outside on a side facing the second unit.

[0011] Since the temperature of the second unit is higher than that of the first unit, an airflow is created between the first and second units. By providing the second vent facing the second unit in addition to the first vent facing the first unit, the air flowing between the first unit and the second unit tends to flow through the storage space in the casing. Air in the storage space, which is heated by heat generated by the bus bar, can therefore be discharged (heat exhaust) to the outside of the storage space using the airflow caused by the temperature difference between the first unit and the second unit.

[0012] In this case, the magnetic detector can be arranged between the first vent and the second vent. With this configuration, the air around the magnetic detector, which has been heated by the heat generated by the bus bar, can be efficiently discharged from the housing by utilizing the airflow between the first vent and the second vent. Therefore, it is possible to suppress an increase in the temperature of the magnetic detector and prevent deterioration in the measurement accuracy of the magnetic detector.

[0013] The magnetic detector can be arranged in a position facing the bus bar. When the magnetic detector is viewed facing the bus bar, that is, viewed in a direction perpendicular to a plate-like surface of the bus bar facing the magnetic detector, at least a portion of the magnetic detector can overlap the bus bar. As a result, the magnetic detector can efficiently detect a magnetic field of the bus bar.

[0014] The current sensor may further include plate-like shielding elements capable of suppressing noise applied to the magnetic detector. The shielding elements may include a first shielding element disposed on a side of the magnetic detector opposite a side on which the bus bar is disposed, and a second shielding element paired with the first shielding element and disposed on a side of the bus bar opposite a side on which the magnetic detector is disposed.

[0015] Since the shielding elements can suppress noise applied to the magnetic detector, the detection accuracy of the current sensor improves.

[0016] The current sensor may further include a shielding member capable of suppressing noise applied to the magnetic detector. A cross-sectional shape of the shielding member when cut along a surface perpendicular to a direction in which the bus bar extends may be U-shaped, and the shielding member may be arranged in such a manner that, when viewed in the direction in which the bus bar extends, it surrounds the bus bar from both sides of the bus bar in a direction perpendicular to a direction in which the bus bar and the magnetic detector overlap, and a side of the bus bar opposite a side in the direction in which the bus bar and the magnetic detector overlap, on which the magnetic detector is arranged.

[0017] Since the U-shaped shielding member surrounding the bus bar from the three sides except the side on which the magnetic detector is arranged is used, when a plurality of bus bars are provided, an effect of noise from the bus bars except the one facing the magnetic detector can be suppressed.

[0018] The current sensor may further include an electronic component separate from the magnetic detector. The electronic component may be arranged in the storage space. With this configuration, a heat effect generated by the bus bar on the electronic component in addition to the magnetic detector can be suppressed.

[0019] A current control system includes the current sensor in the present invention, the first unit and the second unit.

[0020] The first unit may be an inverter including the cooling device, and the second unit may be a motor.

[0021] With this configuration, it is possible to discharge air in the storage space, which is heated by the heat generated by the bus bar, to the outside of the storage space by utilizing the airflow generated between the first unit whose temperature is relatively low and the second unit whose temperature is relatively high, and suppressing a rise in temperature around the magnetic detector. Advantageous effects of the invention

[0022] According to the present invention, air in a storage space heated by heat generated by bus bars can be discharged from the storage space to the outside using an airflow caused by a temperature difference near a current sensor. As a result, it is possible to suppress a temperature increase of magnetic detectors due to heat generated by the bus bars and to provide a current sensor with excellent measurement accuracy. Short description of the drawings [ Fig. 1] Fig. 1 is a perspective view of a current sensor according to an embodiment of the present invention. [ Fig. 2] Fig. 2 is a perspective view illustrating a state in which a cover member and a substrate are omitted from the current sensor according to the embodiment of the present invention. [ Fig. 3] Fig. 3 is a cross-sectional view of the current sensor of Fig. 1. [ Fig. 4] Fig. 4 is a block diagram of a current control system using the current sensor of Fig. 1 includes. [ Fig. 5] Fig. 5 is a block diagram of a power control system according to a modification. [ Fig. 6] Fig. 6 is a perspective view illustrating a state in which a cover member and a substrate are omitted from a current sensor according to another modification. [ Fig. 7] Fig. 7 is a perspective view of a current sensor according to another modification. [ Fig. 8] Fig. 8 is a cross-sectional view of the current sensor of Fig. 7. [ Fig. 9] Fig. 9 is a perspective view of a current sensor according to another modification. [ Fig. 10] Fig. 10 is a cross-sectional view of a current sensor according to another modification. [ Fig. 11] Fig. 11 is a cross-sectional view of a current sensor according to another modification. [ Fig. 12] Fig. Figure 12 shows a perspective view of a conventional current sensor. [ Fig. 13] Fig. 13 is a cross-sectional view of the current sensor of Fig. 12. Description of the embodiments

[0023] An embodiment of the present invention will be described below with reference to the accompanying drawings. In the drawings, the same elements are designated by the same numbers, and descriptions thereof will be omitted. To indicate a positional relationship between elements, reference coordinates are shown in each drawing. The reference coordinates include an X-axis direction in which bus bars extend, a Y-axis direction perpendicular to the X-axis direction on the plate-like surfaces of the bus bars, and a Z-axis direction perpendicular to the plate-like surfaces of the bus bars.

[0024] Fig. 12 is a perspective view of a conventional current sensor 100 and Fig. 13 is a cross-sectional view taken from the current sensor 100 of Fig. 12 in a YZ plane along line AA. As shown in these drawings, in the conventional current sensor 100, a substrate 109 having three magnetic detectors 104 is provided in a storage space 103 in a case 102 formed by a case member 102a with which a portion of bus bars 101 is integrated, and a cover member 102b.

[0025] The storage space 103 is defined by the housing 102, and since there is generally no gap large enough to cause air convection, the heat generated by the bus bars 101 is trapped inside. Therefore, when a current to be measured continuously flowing through the bus bars 101 becomes large, the temperature in the storage space 103 rises due to a heating effect generated by the bus bars 101 and may exceed a heat-resistant temperature of the magnetic detectors 104, thereby reducing the detection accuracy of the current sensor 100.

[0026] When the current sensor 100 measures a current flow between an inverter and a motor, the ends of the bus bars 101 are connected to the inverter, and the other ends of the bus bars 101 are connected to the motor. The inverter includes a cooling device that cools an insulated gate bipolar transistor (IGBT). When a current to be measured flows through the bus bars 101, the motor becomes approximately 170°C to 180°C, for example, and the inverter becomes 100°C or less, meaning that the temperature of the inverter becomes lower than that of the motor.

[0027] As a result, an air flow (convection) is generated near the current sensor 100 due to the difference between the temperature of the motor and that of the inverter.

[0028] The present invention aims to prevent an increase in the temperature of the magnetic detectors 104 and suppress a decrease in the detection accuracy of the current sensor 100 by discharging air heated by the heat generated by bus bars in the storage space 103 to the outside from the storage space 103 using an airflow caused by a difference in temperature around the current sensor. <stromsensor>

[0029] Fig. 1 is a perspective view of a current sensor 10 according to an embodiment of the present invention, and Fig. Fig. 2 is a perspective view illustrating a state in which a cover member 12b and a substrate 19 (see Fig. 3) can be omitted from the current sensor 10. Fig. 3 is a cross-sectional view taken from the current sensor 10 Fig. 1 was cut in a YZ plane along line AA.

[0030] The current sensor 10 includes three bus bars 11 arranged side by side in the Y-axis direction, a housing member 12a, and a cover member 12b, and has a storage space 13 in a housing 12 formed by the housing member 12a and the cover member 12b. Magnetic detectors 14 capable of detecting a magnetic field generated when a current to be measured flows through the bus bars 11 are located in the storage space 13.

[0031] The bus bars 11 are plate-like conductive members extending linearly in a width direction (X-axis direction) of the housing 12, and a part thereof is integrated with the housing member 12a by inserting a molding or the like. A current to be measured, which is a detection target, flows through the bus bars 11, which are made of, for example, copper, brass, aluminum, or the like. Two opposing plate-like surfaces of each of the bus bars 11 are provided in correspondence with a top and a bottom surface (both surfaces in the Z-axis direction) of the housing 12.

[0032] Both ends of each bus bar 11 in the X-axis direction, which are connections to the outside, need not be linearly symmetrical about the Y-axis. Additionally, a portion of each bus bar 11 that does not face the corresponding magnetic detector 14 need not be a flat plate and may, for example, be curved instead.

[0033] The magnetic detectors 14 detect a magnetic field (induced magnetic field) generated when a current to be measured flows through the bus bars 11 and measure a current value of the current to be measured. For example, magnetoresistive elements such as GMR (giant magnetoresistance) or TMR (tunnel magnetoresistance) elements are used as the magnetic detectors 14. These elements utilize a magnetoresistance effect in which electrical resistance changes due to an external magnetic field. The substrate 19 has plate-shaped surfaces parallel to an XY plane, and the magnetic detectors 14 are arranged on one of the plate-shaped surfaces of the substrate 19, which is arranged in the storage space 13 at positions facing the corresponding bus bars 11.At least a portion of the sensor portions of the magnetic detectors 14 faces the corresponding busbars 11 and overlaps the busbars 11 when viewed in the Z-axis. The three magnetic detectors 14 are preferably provided on the same side of the substrate 19.

[0034] As in Fig. 3, in the current sensor 10, plate-like shielding members 16 comprising a first shielding member 16A and a second shielding member 16B are provided for each of three sets of a bus bar 11 and a magnetic detector 14. The first shielding members 16A and the second shielding members 16B are each formed, for example, by stacking a plurality of plate-like metal members having the same shape. Each set of shielding members 16 may instead include only the first shielding member 16A or the second shielding member 16B.

[0035] The first shielding elements 16A are integrated with the cover member 12b and arranged on a side of the magnetic detectors 14 opposite a side on which the bus bars 11 are arranged. The second shielding elements 16B are integrated with the housing member 12a and arranged on a side of the bus bars 11 opposite a side on which the magnetic detectors 14 are arranged. Since the first shielding elements 16A and the second shielding elements 16B suppress the effect of noise on the magnetic detectors 14, the detection accuracy of the current sensor 10 is improved.

[0036] Fig. 4 is a block diagram illustrating a current control system 110 that uses the current sensor 10 of Fig. 1 includes.

[0037] As shown in the drawing, the present invention can be implemented as a current control system 110, which includes the current sensor 10, a first unit 20, and a second unit 30 whose temperature is higher than that of the first unit. When measuring a current flowing between an inverter and a motor of an automobile using the current sensor 10, for example, the first unit 20 is the inverter, which includes a cooling device 21, and the second unit 30 is the motor. In this case, the motor becomes 170°C to 180°C and the inverter becomes 100°C or less, for example, and the air moves near the current sensor 10 due to the temperature difference.

[0038] The ends 11a of the bus bars 11 of the current sensor 10 are connected to the external first unit 20, which includes the cooling device 21, and the other ends 11b are connected to the second unit 30. Since the temperature of the second unit 30 is higher than that of the first unit 20, the difference in temperature causes an air flow (convection) in a direction (X-axis direction) that is Fig. 4 is indicated by two-way arrows.

[0039] As in the Fig. 2 and Fig. As shown in Figure 4, the housing 12 includes first vents 15A penetrating from the inside of the storage space 13 to the outside on a side facing the first unit 20. The housing 12 also includes second vents 15B penetrating from the inside of the storage space 13 to the outside on a side facing the second unit 30. A portion of the airflow in the X-axis direction due to the temperature difference flows through the storage space 13 of the housing 12 via the first vents 15A and the second vents 15B.Therefore, even if the air in the storage space 13 becomes hot due to the heat generated by the bus bars 11, the hot air can be discharged from the storage space 13 to the outside using the airflow caused by the difference in temperature, and it is possible to prevent an increase in the temperature of the magnetic detectors 14 and maintain the detection accuracy of the current sensor 10.

[0040] From the perspective of directing air outside the storage space 13 to the vicinity of the magnetic detectors 14 and preventing hot air from remaining in the storage space 13, it is preferable to dispose the magnetic detectors 14 between the first vent 15A and the second vent 15B. With this configuration, when a large current continuously flows as a current to be measured, it is possible to prevent the heat generated by the bus bars 11 from affecting the magnetic detectors 14 and to maintain the measurement accuracy of the current sensor 10 high.

[0041] Arranging the magnetic detectors 14 between the first vents 15A and the second vents 15B means that at least some of the magnetic detectors 14 are arranged on line segments connecting the first vents 15A and the second vents 15B. The line segments connecting the first vents 15A and the second vents 15B refer to line segments whose points at their ends are located in arbitrary areas of the first vents 15A and the second vents 15B.

[0042] As in the Fig. As shown in FIGS. 1 to 3, the first vents 15A and the second vents 15B are sets of three elongated rectangular holes whose longitudinal direction is the Z-axis direction. Since the first vents 15A and the second vents 15B are configured as a plurality of adjacent slots, it is possible to cool the storage space 13 using airflow caused by a temperature difference and prevent foreign matter from entering the storage space 13.

[0043] In the current sensor 10, three sets of first vents 15A and three sets of second vents 15B are provided, which are the same number as the number of bus bars 11 and the number of magnetic detectors 14. However, the number of first vents 15A and second vents 15B is not limited to three and may be different from the number of bus bars 11 and the number of magnetic detectors 14. < First modification >

[0044] Fig. 5 is a block diagram illustrating a current control system 120 including a current sensor 40 according to a modification.

[0045] The housing 12 of the above-described current sensor 10 has the first vents 15A and the second vents 15B, and uses the airflow caused by a temperature difference between the first unit 20 and the second unit 30 to exhaust hot air in the storage space 13 to the outside. The current sensor 40, on the other hand, differs from the current sensor 10 in that the current sensor 40 has only first vents 15A facing the first unit 20 and the second unit 30, to which the bus bars 11 are connected, and the first unit 20 has a relatively low temperature.

[0046] When a storage space 43 of a housing 42 has only the first vents 15A facing the first unit 20, such as the current sensor 40, and the air in the storage space 13 becomes hot due to the heat generated by the bus bars 11 in the housing 42, a difference in temperature is caused between the bus bars 11 and the first unit 20. As a result, the difference in temperature causes an air flow in a direction of the Fig. 5, i.e., in the X-axis direction. Therefore, as with the current sensor 10, it is possible to discharge the air heated by the heat in the storage space 43 to the outside using the airflow caused by the temperature difference between the first unit 20 and the busbars 11, and to suppress a decrease in the measurement accuracy of the current sensor 40 caused by an increase in the temperature of the magnetic detectors 14.

[0047] Although the air in the storage space 13 is discharged to the outside even if the vents are provided only at positions not facing the first unit 20, efficient ventilation can be achieved by providing vents (first vents 15A) at positions facing the first unit 20. If only second vents 15B are provided, the ventilation efficiency is lower than in the first modification. < Second modification >

[0048] Fig. 6 is a perspective view of a current sensor 50 according to another modification. Although the drawing illustrates a state in which the cover member 12b and the substrate 19 are omitted for convenience of description, the current sensor 50 includes the cover member 12b as in the current sensor 10, and the magnetic detectors 14 are provided on the substrate 19.

[0049] Current sensor 50 differs from current sensor 10 in that current sensor 50 includes bus bars 51 having a different shape than bus bars 11, and second vents 55B are provided at positions corresponding to the shape of bus bars 51. Other components of current sensor 40 are the same as those of current sensor 10.

[0050] As in Fig. 6, the bus bars 51 are bent in the current sensor 50. In this case, the second vents 55B cannot be formed at positions overlapping the first vents 15A in the X-axis direction and the bus bars 51 in the Z-axis direction. Therefore, in the current sensor 50, the first vents 15A are formed at positions overlapping the bus bars 51 in the Z-axis direction, and the second vents 55B are formed on both sides of the bus bars 51 in the Y-axis direction. Thereby, an airflow is formed in a storage space 53 diagonally with respect to a width direction (X-axis direction) of a housing member 52a (housing 52).When the first vents 15A and the second vents 55B are also configured in this way, it is possible to discharge hot air from the storage space 53 to the outside of the storage space 53 using an airflow caused by a temperature difference from the outside, and suppress a decrease in the measurement accuracy of the current sensor 50 caused by an increase in the temperature of the magnetic detectors 14. As with the second vents 55B, the first vents 15A can be formed on both sides of the bus bars 51 in the Y-axis direction. < Third Modification >

[0051] Fig. Fig. 7 is a perspective view of a current sensor 60 according to a further modification, and Fig. Fig. 8 is a cross-sectional view taken of the current sensor 60 of Fig. 7 is sectioned in a YZ plane along line AA. The current sensor 60 differs from the current sensor 10 with respect to the positions in a housing 62 in which first vents 65A and second vents 65B are provided. Other components of the current sensor 60 are the same as those of the current sensor 10.

[0052] The first unit 20, to which the ends 11a of the busbars 11 are connected, and the second unit 30, to which the other ends 11b are connected, are arranged at different positions in accordance with the design of a product. Therefore, the positions at which the first unit 20 and the second unit 30 are arranged are not limited to the X-axis direction of the Fig. 4 shown current sensor 10.

[0053] The one in the Fig. 7 and Fig. The current sensor 60 shown in Figure 8 uses an air flow caused by a difference in temperature when the first unit 20 comprising the cooling device 21 (see Fig. 4), the first unit 30 is disposed on the side of a housing member 62a in the Z-axis direction, and the second unit 30 is disposed on the side of a cover member 62b in the Z-axis direction. Therefore, in order to utilize external airflow, a bottom surface (a surface whose vertical line is parallel to the Z-axis) of the housing member 62a has the first vents 65A, and a top surface (a surface whose vertical line is parallel to the Z-axis) of the cover member 62b has the second vents 65B.

[0054] With this configuration, it is possible to heat air that has been heated by the heat generated by the busbars 11 using an air flow in the direction indicated in Fig. 8, from a storage space 63 to the outside in the Z-axis direction indicated by a double-headed arrow, and to suppress an increase in the temperature of the magnetic detectors 14. To improve the heat dissipation efficiency of the storage space 13 based on air movement in the Z-axis direction, holes penetrating the substrate 19 in the Z-axis direction may be provided in a part of the substrate 19. However, the substrate 19 is provided in the storage space 13 with a gap from the surrounding case member 62a. Therefore, even if no holes are provided, heated air in the storage space 63 can be discharged to the outside using the air movement in the Z-axis direction.

[0055] The positions and the number of the first vents 65A and the second vents 65B can be adjusted accordingly in accordance with the first unit 20 and the second unit 30. As in Fig. 5, the first vents 65A may be provided only in one surface on the side facing the first unit. < Fourth Modification >

[0056] Fig. Fig. 9 is a perspective view of a current sensor 70 according to a further modification, and first vents 75A and second vents 75B are provided in both surfaces of a housing member 72a in the Y-axis direction perpendicular to a direction in which the bus bars 11 extend. When the first unit 20 and the second unit 30 (see Fig. 4 and Fig. 5) are provided on both sides of a casing 72 formed by the casing member 72a and a cover member 72b in a longitudinal direction (Y-axis direction) of the casing 72, therefore, heated air in the storage space 13 can be discharged to the outside using air movement caused by a difference in temperature.

[0057] As described in the second to fourth modifications, the first unit and the second unit are provided at different positions according to the design, and vents are provided at different positions according to the arrangement of the first unit and the second unit. With this configuration, it is possible to discharge the air heated by heat in a storage space of a housing to the outside using an airflow caused by a temperature difference, prevent a temperature rise in the storage space due to heat generated by bus bars when measuring a large current, and maintain the measurement accuracy of a current sensor. < Fifth Modification >

[0058] Fig. Fig. 10 is a cross-sectional view of a current sensor 80 according to another modification and illustrates a structure of a part corresponding to a part of the current sensor 10 in Fig. 1, which is indicated by line AA. The current sensor 80 differs from the current sensor 10 in that the current sensor 80 does not include the plate-like first shielding elements 16A and, instead of the plate-like second shielding elements 16B, includes second shielding elements 86B whose cross-sectional shape, when cut along a direction perpendicular to the direction (X-axis direction) in which the busbars 11 extend, is a U-shape, and other components are the same as those of the current sensor 10.

[0059] The second shielding members 86B are arranged in such a manner that, when viewed in the direction (X-axis direction) in which the bus bars 11 extend, they surround the bus bars 11 from three sides, except for a side on which the magnetic detectors 14 are arranged. That is, the bus bars 11 are surrounded by the second shielding members 86B from both sides of the bus bars 11 in the Y-axis direction and a side opposite the side in the Z-axis direction on which the magnetic detectors 14 are arranged. This makes it possible to suppress an effect from adjacent bus bars 11 other than a bus bar 11 to which each magnetic detector 14 faces, using the corresponding second shielding member 86B.It is therefore possible to suppress an effect of an external magnetic field on the magnetic detectors 14 and improve the detection accuracy of the current sensor 80. < Sixth Modification >

[0060] Fig. 11 is a cross-sectional view of a current sensor 90 according to another modification. Current sensor 90 differs from current sensor 10 in that electronic components 98, different from the magnetic detectors 14, are arranged in the storage space 13 along the magnetic detectors 14, and other components are the same as those of current sensor 10. For example, IC chip components such as capacitors and resistors can be used as electronic components 98.

[0061] Since the housing 12 has the first vents 15A and the second vents 15B in the current sensor 90 as in the current sensor 10, air heated by heat generated by the bus bars 11 can be exhausted from the storage space 13 to the outside using an airflow outside the storage space 13. Therefore, it is possible to prevent an increase in the temperature of the magnetic detectors 14 and the electronic components 98 due to the heat generated by the bus bars 11 and a decrease in the detection accuracy of the current sensor 90.

[0062] The embodiment disclosed herein is an example in every respect, and the subject matter of the present invention is not limited to this embodiment. The subject matter of the present invention is defined not by the description of the above embodiment alone, but by the claims, and is intended to include all modifications equivalent in meaning and scope to the claims. Industrial applicability

[0063] The present invention is effective as a current sensor capable of suppressing a temperature rise of magnetic detectors and a decrease in measurement accuracy of the current sensor by discharging air heated by heat generated by a large current flowing through bus bars to the outside of a storage space and measuring a current between, for example, a motor and an inverter. List of reference symbols 10 Current sensor 11 busbars 11a ends 11b other ends 12 housings 12a Housing element 12b Cover element 13 storage space 14 magnetic detectors 15A first vents 15B second vents 16 shielding elements 16A first shielding elements 16B second shielding elements 19 Substrat 20 first unit 21 Cooling device 30 second unit 40 current sensor 42 housings 43 storage space 50 current sensor 51 busbars 52 housings 52a Housing element 53 storage space 55B second vents 60 current sensor 62 housings 62a Housing element 62b cover element 63 storage space 65A first vents 65B second vents 70 current sensor 72 housings 72a Housing element 72b Cover element 75A first vents 75B second vents 80 current sensor 86B second shielding elements 90 current sensor 98 Electronic Components 100 current sensors 101 busbars 102 housings 102a Housing element 102b Cover element 103 storage space 104 magnetic detectors 109 Substrat 110 Power control system 120 Power control system QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 6462850

[0004] < / stromsensor>

Claims

[1] A current sensor comprising: a busbar through which a current to be measured flows; a magnetic detector capable of detecting a magnetic field generated when the current to be measured flows through the busbar; and a housing having a storage space which accommodates the magnetic detector and with which a part of the bus bar is integrally formed, wherein the current sensor is capable of measuring a current value of the current to be measured from the magnetic field detected by the magnetic detector, wherein one end of the busbar is connected to an external first unit comprising a cooling device, and another end of the busbar is connected to an external second unit whose temperature is higher than the temperature of the first unit, and wherein the housing has a first vent penetrating from an inside of the storage space to an outside on a side facing the first unit. [2] The current sensor according to claim 1, wherein the housing has, in addition to the first vent, a second vent penetrating from the inside of the storage space to the outside on a side facing the second unit. [3] The current sensor according to claim 2, wherein the magnetic detector is arranged between the first vent and the second vent. [4] The current sensor according to claim 1, wherein the magnetic detector is arranged at a position facing the bus bar. [5] The current sensor according to claim 1, further comprising: plate-like shielding elements capable of suppressing noise affecting the magnetic detector, wherein the shielding elements comprise a first shielding element arranged on a side of the magnetic detector opposite a side on which the bus bar is arranged, and a second shielding element paired with the first shielding element and arranged on a side of the bus bar opposite a side on which the magnetic detector is arranged. [6] The current sensor according to claim 1, further comprising: a shielding element capable of suppressing noise applied to the magnetic detector, wherein a cross-sectional shape of the shielding member when cut along a surface perpendicular to a direction in which the bus bar extends is a U-shape, and the shielding member is arranged in such a manner that, when viewed in the direction in which the bus bar extends, it surrounds the bus bar from both sides of the bus bar in a direction perpendicular to a direction in which the bus bar and the magnetic detector overlap, and a side of the bus bar opposite to a side in the direction in which the bus bar and the magnetic detector overlap, on which the magnetic detector is arranged. [7] The current sensor according to claim 1, further comprising: an electronic component which is different from the magnetic detector, wherein the electronic component is arranged in the storage space. [8] A power control system comprising: the current sensor according to claim 1; the first unit; and the second unit. [9] The power control system according to claim 8, wherein the first unit is an inverter including the cooling device and the second unit is a motor.

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