Power conversion device

Abstract

Provided is a power conversion device including an inverter circuit, an alternating current conductor, a magnetic sensor that detects a magnetic field generated when an alternating current flows, a first magnetic body and a second magnetic body that face each other with the alternating current conductor and the magnetic sensor interposed therebetween, and a first housing and a second housing formed of an electrically conductive member, the first housing covering one opening of a space sandwiched by the first magnetic body and the second magnetic body, the second housing covering the other opening of the space, and end portions of each of the first magnetic body and the second magnetic body being formed so as to have a distance to the first housing or the second housing that is smaller than a thickness in an arrangement direction of the first magnetic body and the second magnetic body.

Description

Technical Field

[0001] This invention relates to power conversion devices. Background Technology

[0002] As background technology for the present invention, the following Patent Document 1 discloses a coreless current measuring device that uses a magnetic body to shield the side and lower surface of a magnetic sensor so as not to cause a response delay in current detection when magnetic noise enters from the outside of the magnetic shield.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2019-184355 Summary of the Invention

[0006] The technical problem that the invention aims to solve

[0007] Based on the structure described in Patent Document 1, in order to meet further customer requirements and to achieve the same effect even with a thin power conversion device structure, the object of the present invention is to provide a power conversion device that combines thinness and suppression of magnetic interference.

[0008] Technical means for solving technical problems

[0009] The power conversion device includes: an inverter circuit for converting direct current into alternating current; an alternating current conductor for conducting the alternating current; a magnetic sensor for detecting the magnetic field generated when the alternating current flows in the alternating current conductor; a first magnetic body and a second magnetic body opposite to each other separated by the alternating current conductor and the magnetic sensor; and a first housing and a second housing formed of conductive components, the first housing covering an opening in a space sandwiched between the first magnetic body and the second magnetic body, and the second housing covering another opening in the space, wherein the ends of the first magnetic body and the second magnetic body are formed such that the distance to the first housing or the second housing is smaller than the thickness of the first magnetic body and the second magnetic body in the direction of their alignment.

[0010] The effects of the invention

[0011] According to the present invention, a power conversion device that combines thinness and suppression of magnetic interference can be provided. Attached Figure Description

[0012] Figure 1 This is a perspective view of the external appearance of a power conversion device according to one embodiment of the present invention, and an internal view of the housing with the housing cover removed.

[0013] Figure 2These are exploded perspective views and block diagrams of a power conversion device according to one embodiment of the present invention.

[0014] Figure 3 These are perspective views and cross-sectional views (AA) of the peripheral portion of the magnetic sensor according to the first embodiment of the present invention.

[0015] Figure 4 Viewed from the R direction Figure 3 The cross-sectional view at (b).

[0016] Figure 5 This is a cross-sectional view of the peripheral portion of the magnetic sensor according to the first embodiment of the present invention.

[0017] Figure 6 This is an explanatory diagram regarding the distance between the housing and the magnetic body according to the first embodiment of the present invention.

[0018] Figure 7 This is a cross-sectional view of the peripheral portion of the magnetic sensor according to the second embodiment of the present invention.

[0019] Figure 8 This is a cross-sectional view of the peripheral portion of the magnetic sensor according to the third embodiment of the present invention.

[0020] Figure 9 This is a cross-sectional view of the peripheral portion of the magnetic sensor according to the fourth embodiment of the present invention.

[0021] Figure 10 This is a cross-sectional view of the peripheral portion of the magnetic sensor according to the fifth embodiment of the present invention.

[0022] Figure 11 This is a cross-sectional view of the peripheral portion of the magnetic sensor according to the sixth embodiment of the present invention.

[0023] Figure 12 This is a diagram of the magnetic field detection sensitivity correction unit according to the seventh embodiment of the present invention. Detailed Implementation

[0024] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The following description and drawings are examples for illustrating the present invention; appropriate omissions and simplifications have been made to make the description clear and easy to understand. The present invention can also be implemented in various other ways. Unless otherwise specified, each constituent element can be single or multiple.

[0025] The positions, sizes, shapes, and extents of the constituent elements shown in the accompanying drawings are for ease of understanding and do not necessarily represent actual positions, sizes, shapes, or extents. Therefore, this invention is not limited to the positions, sizes, shapes, and extents shown in the accompanying drawings.

[0026] (Structure of the first embodiment and the power conversion device)

[0027] Figure 1 This is a perspective view of the external appearance of a power conversion device according to one embodiment of the present invention, and an internal view of the housing with the housing cover removed.

[0028] The housing 2a of the power conversion device includes: a DC input terminal 22 for supplying DC current to the inverter circuit housed inside the housing 2a; an AC conductor 6 for outputting AC current from the inverter to the outside; a refrigerant inlet 21 for supplying refrigerant to the interior of the housing 2a for cooling the inverter circuit; and a control signal input / output terminal 7 for transmitting control signals of the inverter circuit to an external control device. The bottom (base) of the housing 2a is a conductive component. By sealing the interior with a cover of the housing 2a, foreign objects and water are prevented from entering from the outside.

[0029] Inside the housing 2a are housed: a capacitor 25 that smooths the input current from the DC input terminal 22; a main circuit section 24 that converts DC current into AC current; a refrigerant flow path 23 that cools the main circuit section 24; a magnetic field detection circuit board 8 that detects the magnetic flux generated by the AC conductor 6; and a first housing 1 that covers the magnetic field detection circuit board 8. The first housing 1 is a conductive component. The magnetic field detection circuit board 8 has three magnetic sensors 5 corresponding to the three-phase AC conductors 6 respectively (see reference). Figure 3 ), and is fixed to the second housing 2 by screws or the like.

[0030] Figure 2 These are exploded perspective views and block diagrams of a power conversion device according to one embodiment of the present invention.

[0031] The main circuit section 24 of the inverter circuit consists of a DC input terminal 22, a capacitor 25, an IGBT element 26, a diode element 27, and an AC conductor 6. The capacitor 25 is connected in parallel with the positive and negative terminals of the DC input terminal 22. The IGBT element 26 and the diode element 27, which function as switching elements by being connected in series, form a half-bridge circuit by being connected in parallel with the capacitor 25. The IGBT element 26 converts DC current into AC current by being switched on or off (ON / OFF) based on a control circuit (not shown).

[0032] Refrigerant flow paths 23 are provided on the upper and lower main surfaces of the main circuit section 24. Long-life coolant or other refrigerant supplied from the outside via the refrigerant inlet 21 flows through the interior of the refrigerant flow paths 23. Fins are formed inside the refrigerant flow paths 23 to improve cooling performance. The main circuit section 24 is sealed with insulating resin to insulate it from the refrigerant flow paths 23 and the second housing 2.

[0033] The heat dissipation surface of the main circuit section 24, which contacts the refrigerant flow path 23, is coated with thermal grease or the like to improve its adhesion to the refrigerant flow path 23 and reduce contact thermal resistance. The main circuit section 24 is constructed by mounting IGBT elements 26 and diode elements 27 on wiring materials such as printed circuit boards.

[0034] The main circuit section 24 and the capacitor 25 are electrically connected by solder or other bonding materials. The AC conductor 6 is electrically connected to the main circuit section 24 by screw fastening, soldering, or other means.

[0035] Figure 3 These are perspective views and cross-sectional views (AA) of the peripheral portion of the magnetic sensor according to the first embodiment of the present invention.

[0036] The output signal of the magnetic sensor 5 is transmitted from the control signal input / output terminal 7 to an inverter control circuit (not shown) outside the housing 2a via wiring on the magnetic field detection circuit board 8. In addition to the magnetic sensor 5, the magnetic field detection circuit board 8 also houses a power supply circuit that supplies power to the magnetic sensor 5. The alternating current conductor 6 passes through the lower surface of the magnetic sensor 5 and protrudes towards the lower surface of the first housing 1, thereby preventing interference from the magnetic flux of the motor current to electronic components other than the magnetic sensor 5.

[0037] The first magnetic body 3 and the second magnetic body 4 are formed to be longer in the left-right direction on the paper compared to the magnetic sensor 5. As a result, magnetic flux that detours from the left and right sides of the first magnetic body 3 and the second magnetic body 4 can be suppressed.

[0038] Figure 4 Viewed from the R direction Figure 3 (b) is a cross-sectional view.

[0039] The first magnetic body 3 and the second magnetic body 4 are constructed from an electromagnetic steel plate, a ferrite core, etc., and are respectively positioned opposite each other, separated by an AC conductor (wiring) 6 and a magnetic sensor 5. The first housing 1 covers one opening of the space sandwiched between the first magnetic body 3 and the second magnetic body 4, and the second housing 2 covers the other opening. This concentrates the lateral magnetic flux generated when current flows through the AC conductor 6, preventing leakage to the surrounding environment. The first magnetic body 3 and the second magnetic body 4 are fixed in a through-hole (not shown) formed in the magnetic field detection circuit board 8. Through this through-hole, the positions of the magnetic bodies 3 and 4 are defined as symmetrical about the center of the magnetic sensor 5 and the AC conductor 6.

[0040] Multiple magnetic sensors 5 are arranged on the magnetic field detection circuit board 8 in the direction of the arrangement of the first magnetic body 3 and the second magnetic body 4. They are positioned above each phase of the AC conductor 6 to detect the magnetic flux generated by the current flowing through each phase. The magnetic sensors 5 reduce interference from external magnetic flux by detecting magnetic flux in the left-right direction of the paper. Furthermore, the magnetic sensors 5 can improve their magnetic flux detection sensitivity by being close to the AC conductor 6.

[0041] Figure 5 This is a cross-sectional view of the peripheral portion of the magnetic sensor according to the first embodiment of the present invention.

[0042] The first housing 1 and the second housing 2 are made of non-magnetic conductors such as aluminum and are arranged to cover the opening of the space sandwiched between the first magnetic body 3 and the second magnetic body 4. Thus, the magnetic flux 9 generated when the motor current 11 flows through the alternating current conductor 6 induces a current 10 in the first housing 1 and the second housing 2. The magnetic flux generated by this induced current 10 shields the magnetic flux 9 generated by the motor current 11. By employing a structure where the magnetic bodies 3 and 4 are arranged only between the alternating current conductors 6 of each phase and to the side of the magnetic sensor 5, and without providing a magnetic shield in the height direction (vertical direction on paper), a thinner profile is achieved, and magnetic flux leakage from this space to other phases is suppressed.

[0043] According to this structure, it is possible to prevent the magnetic flux 9 of the motor current 11 flowing through the AC conductor 6 from interfering with the magnetic sensors 5 and the surrounding circuits without adding magnetic materials to the upper surface (top surface) of the magnetic sensor 5 and the lower surface (bottom surface) of the AC conductor 6. This allows for both a thinner power conversion device and improved current detection accuracy. Furthermore, since the magnetic materials 3 and 4 that suppress magnetic flux 9 leakage and the housings 1 and 2 are separate in this structure, assemblability is improved.

[0044] The first housing 1 is configured to cover the magnetic field detection circuit board 8, serving as a fixed object when a control circuit board (not shown) is configured on the upper part, and a box potential surface is formed broadly on the lower surface of the control circuit board, thereby stabilizing the potential of the control circuit.

[0045] The AC conductor 6 is made of a conductor such as copper and is electrically connected to the output terminal of the power module and the motor by welding and screw fixing. Furthermore, the AC conductor 6 is fixed to the second housing 2 via insulating material 28. Therefore, the relative positions of the AC conductor 6, the magnets 3 and 4, and the magnetic sensor 5 are determined by the second housing 2 and the magnetic field detection circuit board 8.

[0046] Figure 6 This is an explanatory diagram regarding the distance between the housing and the magnetic body according to the first embodiment of the present invention.

[0047] The thickness 12 in the arrangement direction of the first magnetic body 3 and the second magnetic body 4 refers to the thickness of the portion (end of the magnetic body) of the first magnetic body 3 or the second magnetic body 4 closest to the first housing 1 or the second housing 2, respectively. The distance 13 from the end of the first magnetic body 3 or the second magnetic body 4 to the first housing 1 or the second housing 2 refers to the distance between the closest portion of the first magnetic body 3 or the second magnetic body 4 and the first housing 1 or the second housing 2. The magnetic bodies 3 and 4 are arranged such that the distance 13 is smaller than the thickness 12 of the ends of the magnetic bodies 3 and 4. As long as this condition is met, the shape of the central portion of the magnetic bodies 3 and 4 is not limited; for example, the central portion of the magnetic bodies 3 and 4 can be tapered. In addition, the magnetic bodies 3 and 4 can also be in contact with the housings 1 and 2.

[0048] (Second Implementation)

[0049] Figure 7 This is a cross-sectional view of the peripheral portion of the magnetic sensor according to the second embodiment of the present invention.

[0050] The first housing 1 ensures space for mounting the electronic component 14. On the surface opposite the second housing 2, there is a protrusion 1a on the upper surface of the magnetic sensor 5, the first magnetic body 3, the second magnetic body 4, and the AC conductor 6. The protrusion 1a brings the ends of the first magnetic body 3 and the second magnetic body 4 close to the first housing 1. With this structure, even when the magnetic field detection circuit board 8 mounts an electronic component 14 larger than the magnetic sensor 5, it is not necessary to increase the size of the first magnetic body 3 and the second magnetic body 4. Furthermore, they are arranged such that the distance to the first housing 1 or the second housing 2 is smaller than the thickness 12 in the arrangement direction of the first magnetic body 3 and the second magnetic body 4.

[0051] (Third Implementation)

[0052] Figure 8 This is a cross-sectional view of the peripheral portion of the magnetic sensor according to the third embodiment of the present invention.

[0053] The first housing 1 has an outwardly recessed portion 1b on the upper surface of the magnetic sensor 5, the first magnetic body 3, the second magnetic body 4, and the AC conductor 6. Through the recessed portion 1b, the sides of the first magnetic body 3 and the second magnetic body 4 are covered by the first housing 1, thereby suppressing the leakage of magnetic flux to the sides (left-right direction on the paper) from the gap between the first magnetic body 3 and the second magnetic body 4 and the first housing 1.

[0054] (Fourth Implementation)

[0055] Figure 9 This is a cross-sectional view of the peripheral portion of the magnetic sensor according to the fourth embodiment of the present invention.

[0056] The first magnetic body 3 and the second magnetic body 4 each have a magnetic body protrusion 15 on their respective opposing surfaces. The extension line of the protrusion of each magnetic body protrusion 15 is formed on one side of the first housing 1 and the second housing 2, relative to the upper surface of the magnetic sensor 5 and the lower surface of the AC conductor 6. In this way, by providing the protrusion 15 on the opposing surfaces of the first magnetic body 3 and the second magnetic body 4, the magnetic flux of the motor current flowing in the AC conductor 6 is guided to the magnetic body protrusion 15, and the leakage of magnetic flux from the space sandwiched between the magnetic body protrusions 15 of the first magnetic body 3 and the second magnetic body 4 or their openings can be suppressed.

[0057] (Fifth Implementation)

[0058] Figure 10 This is a cross-sectional view of the peripheral portion of the magnetic sensor according to the fifth embodiment of the present invention.

[0059] The first magnetic body 3 and the second magnetic body 4 each have a magnetic body protrusion 15, which is fixed to the magnetic field detection circuit board 8 to determine their height positions. This allows for the determination of the relative positions of the first magnetic body 3 and the second magnetic body 4 with the magnetic sensor 5 with good accuracy.

[0060] Furthermore, as a fixing method, adhesive can be applied to the protrusions 15 of the first magnetic body 3 and the second magnetic body 4 to fix the magnetic bodies 3 and 4 to the magnetic field detection circuit board 8. In addition, a housing potential wiring (not shown) is arranged around the through hole 8a of the magnetic field detection circuit board 8 for inserting the first magnetic body 3 and the second magnetic body 4. By soldering the first magnetic body 3 and the second magnetic body 4 to the housing potential wiring, the potential of the first magnetic body 3 and the second magnetic body 4 can be determined.

[0061] (Sixth Implementation Method)

[0062] Figure 11 This is a cross-sectional view of the peripheral portion of the magnetic sensor according to the sixth embodiment of the present invention.

[0063] In this embodiment, instead of the aforementioned AC conductor 6, an AC wiring 6a is provided on the magnetic field detection circuit board 8, through which the motor current 11 flows. By providing the AC wiring 6a on the back side of the surface of the magnetic field detection circuit board 8 where the magnetic sensor 5 is mounted, the creepage distance (surface distance) 29 required for insulation between the magnetic sensor 5 and the AC wiring 6a can be ensured, while simultaneously bringing the magnetic sensor 5 closer to the AC wiring 6a. This improves the sensitivity of the magnetic sensor 5 in detecting magnetic flux. Furthermore, because the positions of the AC wiring 6a and the magnetic sensor 5 are correctly determined, the detection accuracy of the magnetic sensor 5 is improved.

[0064] (Seventh Implementation)

[0065] Figure 12 This is a diagram of the magnetic field detection sensitivity correction unit according to the seventh embodiment of the present invention.

[0066] Magnetic sensor 5 detects the magnetic flux of the motor current flowing through AC conductor 6 and outputs the detected magnetic flux value to magnetic flux detection sensitivity correction unit 17. Angle sensor 20 is connected to the motor rotor and outputs a rotor position signal to speed conversion unit 19. Based on the rotor position signal input from angle sensor 20, speed conversion unit 19 outputs the angular velocity of the motor rotor to magnetic flux detection sensitivity correction unit 17. This angular velocity corresponds to the frequency of the motor current flowing through AC conductor 6. Furthermore, magnetic flux detection sensitivity correction unit 17 and speed conversion unit 19 are mounted on... Figure 1 The control signal input / output terminals are connected to a control unit (not shown) outside the housing.

[0067] In the flux detection sensitivity correction unit 17, a relationship between the angular velocity of the motor rotor and the flux detection sensitivity of the magnetic sensor 5 is preset. Based on this relationship, a corrected flux detection value is calculated using the flux detection value input from the magnetic sensor 5 and the angular velocity input from the speed conversion unit 19, and then output to the current calculation unit 18. The current calculation unit 18 calculates the motor current based on the preset relationship between the flux detection value and the motor current, according to the input corrected flux detection value. Furthermore, the current calculation unit 18 is mounted on a... Figure 1 The control signal input / output terminals are connected to a control unit (not shown) outside the housing.

[0068] Therefore, the change in the magnetic flux detection sensitivity of the magnetic sensor 5, which is affected by the induced current 10 generated in the first housing 1 and the second housing 2, can be corrected, thereby improving the detection accuracy of the motor current.

[0069] Based on the first to seventh embodiments of the present invention described above, the following effects can be obtained.

[0070] (1) The power conversion device includes: an inverter circuit for converting direct current to alternating current, an AC conductor 6 for conducting the AC current, a magnetic sensor 5 for detecting the magnetic field generated when the AC current flows through the AC conductor, a first magnetic body 3 and a second magnetic body 4 sandwiching (or separating) the AC conductor 6 and the magnetic sensor 5, and a first housing 1 and a second housing 2 formed of conductive components. The first housing 1 covers one opening of the space sandwiched between the first magnetic body 3 and the second magnetic body 4, and the second housing 2 covers the other opening of the space. The ends of the first magnetic body 3 and the second magnetic body 4 are formed such that the distance to the first housing 1 or the second housing 2 is smaller than the thickness of the first magnetic body 3 and the second magnetic body 4 in the direction of their arrangement. Therefore, a power conversion device that balances thinness and suppression of magnetic interference can be provided.

[0071] (2) The first housing 1 has a protrusion 1a on the surface opposite to the second housing 2, which protrudes toward the second housing 2. A magnetic sensor 5, a first magnetic body 1, a second magnetic body 2, and an AC conductor 6 are disposed between the protrusion 1a and the second housing 2. Thus, when an electronic component larger than the magnetic sensor 5 is mounted, it is not necessary to increase the size of the first magnetic body 3 and the second magnetic body 4.

[0072] (3) The first housing 1 has a recess 1b on the surface opposite to the second housing 2, which is recessed in a direction away from the second housing 2. A magnetic sensor 5, a first magnetic body, a second magnetic body, and an AC conductor 6 are disposed between the recess 1b and the second housing 2. As a result, magnetic flux leakage from the gap between the first magnetic body 3 and the second magnetic body 4 and the first housing 1 to the side (left-right direction on the paper) can be suppressed.

[0073] (4) The first magnetic body 3 and the second magnetic body 4 each have magnetic body protrusions 15 facing each other. The extension line of each protrusion of the magnetic body protrusion 15 is formed on one side of the first housing 1 and the second housing 2, relative to the upper surface of the magnetic sensor 5 and the lower surface of the AC conductor 6. As a result, the magnetic flux of the motor current flowing in the AC conductor 6 is guided to the magnetic body protrusions 15, and the magnetic flux leaking from the space or its opening between the magnetic body protrusions 15 of the first magnetic body 3 and the second magnetic body 4 to the surroundings is suppressed.

[0074] (5) Includes a magnetic field detection circuit board 8 with a magnetic sensor 5 configured thereon. The first magnetic body 3 and the second magnetic body 4 have magnetic body protrusions 1a, which fix the first magnetic body 3 and the second magnetic body 4 to the magnetic field detection circuit board 8 respectively. As a result, the relative positions of the first magnetic body 3 and the second magnetic body 4 with the magnetic sensor 5 can be determined with good accuracy, and the potentials of the first magnetic body 3 and the second magnetic body 4 can also be determined.

[0075] (6) A magnetic field detection circuit board 8 includes a magnetic sensor 5. The AC conductor 6 is formed by wiring provided on the magnetic field detection circuit board 8. The magnetic sensor 5 is disposed on the side of the magnetic field detection circuit board 8 where the AC conductor 6 is not disposed. This ensures the creepage distance required for insulation between the magnetic sensor 5 and the AC wiring 6a, while simultaneously increasing the sensitivity of the magnetic sensor 5 in detecting magnetic flux by bringing the magnetic sensor 5 close to the AC wiring 6a. Furthermore, because the positions of the AC wiring 6a and the magnetic sensor 5 can be accurately determined, the detection accuracy of the magnetic sensor 5 is improved.

[0076] (7) Includes: a speed conversion unit 19 that converts the rotor position signal output from the angle sensor 20 connected to the rotor of the motor into angular velocity, and a magnetic flux detection sensitivity correction unit 17 that corrects the magnetic flux detection value output from the magnetic sensor 5. The magnetic flux detection sensitivity correction unit 17 corrects the magnetic flux detection value based on the magnetic flux detection value output from the magnetic sensor 5, the angular velocity output from the speed conversion unit 19, and a preset relationship between the angular velocity and the magnetic flux detection sensitivity. Therefore, changes in the magnetic flux detection sensitivity of the magnetic sensor 5 caused by the induced current 10 generated in the first housing 1 and the second housing 2 can be corrected, improving the detection accuracy of the motor current.

[0077] Furthermore, the present invention is not limited to the embodiments described above, and various modifications and other structural combinations can be made without departing from its spirit. Additionally, the present invention is not limited to having all the structures described in the above embodiments, but also includes arrangements in which a portion of the structure is omitted.

[0078] Explanation of reference numerals in the attached figures

[0079] 1 First shell

[0080] 1a convex part

[0081] 1b concave part

[0082] 2. Second housing (base part)

[0083] 2A Inverter Housing (Complete)

[0084] 3 First magnetic body

[0085] 4. Second magnetic body

[0086] 5 magnetic sensors

[0087] 6 AC conductors

[0088] 6A AC conductor wiring

[0089] 7 Control signal input / output terminals

[0090] 8 Circuit boards for magnetic field detection

[0091] 8a Through Hole

[0092] 9 magnetic flux

[0093] 10 Induced Current

[0094] 11 Motor Current

[0095] Thickness in 12 arrangement directions

[0096] 13. Distance between the end of the magnetic body and the shell

[0097] 14 Electronic components

[0098] 15. Magnetic protrusion

[0099] 17. Magnetic Flux Detection Sensitivity Correction Unit

[0100] 18 Current Calculation Department

[0101] 19 Speed ​​Conversion Unit

[0102] 20 Angle Sensor

[0103] 21 Refrigerant inlet

[0104] 22 DC input terminals

[0105] 23 Refrigerant Flow Path

[0106] 24 Main Circuit Section

[0107] 25 Capacitor

[0108] 26 IGBT components

[0109] 27 Diode Components

[0110] 28 Insulation materials

[0111] 29. Creepage distance.

Claims

1. A power conversion device, characterized in that, include: An inverter circuit that converts direct current into alternating current; An alternating current conductor that conducts the alternating current; A magnetic sensor that detects the magnetic field generated when the alternating current flows in the alternating conductor; A first magnetic body and a second magnetic body facing each other, separated by the alternating current conductor and the magnetic sensor; and The first and second housings are formed by conductive components. The first housing and the second housing together form a housing for housing the AC conductor, the magnetic sensor, the first magnetic body, and the second magnetic body. The first housing covers one opening of the space sandwiched between the first magnetic body and the second magnetic body, and the second housing covers the other opening of the space. The distance from each end of the first and second magnetic bodies to the first or second housing is smaller than the thickness of each of the first and second magnetic bodies in the direction in which they are arranged. The first magnetic body and the second magnetic body each have magnetic body protrusions that are opposite to each other. The extension lines of the convex portions of each of the magnetic protrusions are formed on one side of the first housing and the second housing, relative to the upper surface of the magnetic sensor and the lower surface of the AC conductor.

2. A power conversion device, characterized in that, include: An inverter circuit that converts direct current into alternating current; An alternating current conductor that conducts the alternating current; A magnetic sensor that detects the magnetic field generated when the alternating current flows in the alternating conductor; A first magnetic body and a second magnetic body facing each other, separated by the alternating current conductor and the magnetic sensor; and The first and second housings are formed by conductive components. The first housing and the second housing together form a housing for housing the AC conductor, the magnetic sensor, the first magnetic body, and the second magnetic body. The first housing covers one opening of the space sandwiched between the first magnetic body and the second magnetic body, and the second housing covers the other opening of the space. The distance from each end of the first and second magnetic bodies to the first or second housing is smaller than the thickness of each of the first and second magnetic bodies in the direction in which they are arranged. The power conversion device includes a circuit board for magnetic field detection equipped with the magnetic sensor. The first magnetic body and the second magnetic body have magnetic body protrusions. The magnetic protrusions fix the first magnetic body and the second magnetic body to the magnetic field detection circuit board, respectively.

3. A power conversion device, characterized in that, include: An inverter circuit that converts direct current into alternating current; An alternating current conductor that conducts the alternating current; A magnetic sensor that detects the magnetic field generated when the alternating current flows in the alternating conductor; A first magnetic body and a second magnetic body facing each other, separated by the alternating current conductor and the magnetic sensor; and The first and second housings are formed by conductive components. The first housing and the second housing together form a housing for housing the AC conductor, the magnetic sensor, the first magnetic body, and the second magnetic body. The first housing covers one opening of the space sandwiched between the first magnetic body and the second magnetic body, and the second housing covers the other opening of the space. The distance from each end of the first and second magnetic bodies to the first or second housing is smaller than the thickness of each of the first and second magnetic bodies in the direction in which they are arranged. The power conversion device includes: A velocity converter converts the rotor position signal output from the angle sensor connected to the rotor of the motor into angular velocity. and A magnetic flux detection sensitivity correction unit that corrects the magnetic flux detection value output by the magnetic sensor. The magnetic flux detection sensitivity correction unit corrects the magnetic flux detection value based on the magnetic flux detection value output from the magnetic sensor, the angular velocity output from the velocity conversion unit, and a preset relationship between the angular velocity and the magnetic flux detection sensitivity.

4. The power conversion device as described in any one of claims 1 to 3, characterized in that: The first housing has a protrusion on the surface opposite to the second housing, which protrudes toward the second housing. The magnetic sensor, the first magnetic body, the second magnetic body, and the AC conductor are disposed between the protrusion and the second housing.

5. The power conversion device as described in any one of claims 1 to 3, characterized in that: The first housing has a recess on the surface opposite to the second housing, formed by the recess in a direction away from the second housing. The magnetic sensor, the first magnetic body, the second magnetic body, and the AC conductor are disposed between the recess and the second housing.

6. The power conversion device as described in claim 1 or 3, characterized in that: Includes a circuit board for detecting a magnetic field, incorporating the aforementioned magnetic sensor. The alternating current conductor is formed by wiring disposed on the circuit board for magnetic field detection. The magnetic sensor is disposed on the side of the magnetic field detection circuit board that does not have the AC conductor.

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