Motor control device

Abstract

Provided is a motor control device capable of suppressing variation in a separation distance between an electrode to be detected and a magnetic detection element.　This motor control device includes a base block 20, a support column part 13A, a substrate, an electrode for energization, and a magnetic detection element. At least a part of a power control circuit is arranged in the base block 20. The support column part 13A is protruded from the base block 20. The substrate is fixed to the base block 20 via the support column part 13A. The electrode for energization is connected to the power control circuit. The magnetic detection element is attached to a position close to the electrode of the substrate, and detects a magnetic field caused by a current flowing through the electrode. The magnetic detection element is arranged in the vicinity of a support part including the support column part 13A at an end part of the substrate in an extension direction thereof.

Description

Motor control device

[0001] The present invention relates to a motor control device.

[0002] A known motor control device converts DC power supplied from a battery into AC power and drives a motor with the converted AC power. This type of motor control device must accurately detect the input current value from the battery and the output current value to the motor and control each component based on these detected current values. To address this issue, a current sensor is installed around the periphery of a current-carrying electrode (bus bar) connected to a power control circuit (see, for example, Patent Document 1).

[0003] The current sensor described in Patent Document 1 has a magnetic core and a Hall element (magnetic detection element) arranged around a current-carrying electrode (bus bar) connected to a power control circuit. This current sensor uses the magnetic core to amplify a magnetic field generated by a current flowing through the bus bar, and then uses the Hall element to detect the magnetic field amplified by the magnetic core.

[0004] JP 2012-37298 A

[0005] The current sensor described in Patent Document 1 has a structure in which a magnetic core and a Hall element are arranged around the periphery of a current-carrying electrode (bus bar), so the provision of the magnetic core increases the size of the entire device and increases manufacturing costs.

[0006] To address this issue, researchers have recently been studying the use of Hall elements or other magnetic detection elements to detect the magnetic field generated around the electrodes, without using a magnetic core. However, even if the magnetic detection element is placed close enough to the electrodes, even a slight change in the distance between the magnetic detection element and the electrodes can cause large fluctuations in the detected current value. Therefore, when using a motor control device in equipment that is expected to be subject to large vibrations, such as in a vehicle, there is a concern that the detection accuracy of the current flowing through the electrodes will decrease.

[0007] SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a motor control device that can suppress fluctuations in the distance between the electrode, which is the detection target, and the magnetic detection element.

[0008] In order to solve the above problems, the motor control device according to the present invention employs the following configuration: That is, a first aspect of the motor control device according to the present invention includes a base block on which at least a portion of a power control circuit is disposed, a support column protruding from the base block, a circuit board fixed to the base block via the support column, current-carrying electrodes connected to the power control circuit, and a magnetic detection element attached to the circuit board in proximity to the electrode and detecting a magnetic field caused by a current flowing through the electrode, the magnetic detection element being disposed near a portion supported by the support column at an end of the circuit board in the extension direction.

[0009] In a motor control device with this configuration, the end of the substrate in its extension direction is supported by a base block via a support column. When external vibrations are input to the substrate, the amplitude of the vibration in the central region tends to increase. In contrast, the support column at the end of the substrate in its extension direction is easily suppressed by the support column, and does not vibrate with a large amplitude even when external vibrations are input. Therefore, a magnetic detection element disposed near the support column at the end of the substrate in its extension direction does not vibrate significantly even when external vibrations are input. Therefore, when this configuration is adopted, fluctuations in the separation distance between the electrode and the magnetic detection element are suppressed.

[0010] A second aspect of the motor control device of the present invention is the motor control device of the first aspect, wherein the electrodes are formed by plate-shaped bus bars fixed to the base block, and a bent portion is provided in a part of the bus bar that is bent so as to be close to the magnetic detection element.

[0011] In this case, even if the distance between the fixed portion of the bus bar and the substrate is large, by bringing the bent portion of the bus bar closer to the substrate, it is possible to sufficiently narrow the distance between the bus bar (electrode) that is the detection target and the magnetic detection element.

[0012] A third aspect of the motor control device of the present invention is a motor control device according to the first or second aspect, in which a plurality of the electrodes are provided, a plurality of magnetic detection elements are provided in a row horizontally along one edge of the substrate in the extension direction, and the one edge of the substrate is fixed to the base block via a plurality of the support portions.

[0013] In this case, one edge of the substrate is supported by the base block by the plurality of support posts, thereby increasing the rigidity of the one edge of the substrate. The plurality of magnetic detection elements are arranged in a row horizontally along the one edge of the second substrate with increased rigidity, thereby efficiently suppressing variations in the distance between the plurality of electrodes and the corresponding plurality of magnetic detection elements.

[0014] A fourth aspect of the present invention is a motor control device according to the third aspect, wherein the electrodes include a pair of battery-side bus bars connected to a battery and three motor-side bus bars connected to a three-phase power supply unit of the motor, the battery-side bus bars being arranged on the outside of the three motor-side bus bars arranged side by side, and the magnetic detection elements being arranged in proximity to one of the battery-side bus bars and in proximity to each of the three motor-side bus bars on the outside of the arrangement.

[0015] In this case, the input current from the battery can be detected by a magnetic detection element arranged close to one of the battery-side bus bars. Two of the three-phase output currents from the motor can be detected by two magnetic detection elements arranged close to the two outermost motor-side bus bars in the arranging direction. Furthermore, the remaining one-phase output current from the motor can be calculated based on the detection value from the two magnetic detection elements arranged close to the two outermost motor-side bus bars in the arranging direction. Therefore, when this configuration is adopted, the input current and output current can be reliably detected using the minimum number of magnetic detection elements required. Therefore, when this configuration is adopted, the current detection unit can be made smaller and lighter.

[0016] A fifth aspect of the present invention is a motor control device according to the fourth aspect, wherein the support pillars are respectively arranged at approximately midpoints between one motor-side bus bar on the outside in the arrangement direction and one of the battery-side bus bars adjacent to the motor-side bus bar, and at approximately midpoints between another motor-side bus bar on the outside in the arrangement direction and the other battery-side bus bar adjacent to the motor-side bus bar.

[0017] In this case, the two support columns supporting one edge of the board can efficiently suppress fluctuations in the magnetic detection element for detecting the input current and the magnetic detection element for detecting the output current. Therefore, when this configuration is adopted, the number of support columns protruding from the base block can be reduced while ensuring sufficient support rigidity for the board, thereby further reducing the size and weight of the entire device.

[0018] In the motor control device of the present invention, the magnetic detection element is positioned near the support portion formed by the support pillar portion at the end of the extension direction of the substrate, so that fluctuations in the distance between the electrode and the magnetic detection element can be suppressed even if vibration input is received from outside.

[0019] 1 is a perspective view of the motor control device according to the embodiment with the upper cover removed, a perspective view of the motor control device according to the embodiment with the second board removed from the motor control device according to the embodiment with the upper cover removed, and a front view of the motor control device according to the embodiment with the second board removed from the motor control device according to the embodiment with the upper cover removed.

[0020] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0021] FIG. 1 is a perspective view of the motor control device 1 of this embodiment with the top cover removed. FIG. 2 is a perspective view of the motor control device 1 with the second board 14 (board) removed from FIG. 1 . FIG. 3 is a front view of the motor control device 1 corresponding to the view indicated by arrow III in FIG. 1 . The motor control device 1 has an inverter function that converts DC power supplied from a battery (not shown) into AC power and drives a motor (not shown) (AC motor) with the converted AC power. The motor control device 1 has a thin, rectangular case 10 with one open side. A plurality of fins 10a for heat dissipation protrude from the outer surface of the case 10. For ease of explanation, the side of the case 10 with the opening will be referred to as the "top" and the opposite side will be referred to as the "bottom."

[0022] A first substrate 11 and a plurality of electrolytic capacitors 12 (see FIG. 2 ) are housed and arranged inside the opening of the case 10. Additionally, a plurality of support columns 13A, 13B, and 13C are provided on the case 10, protruding upward. A second substrate 14 is supported on the upper portions of the support columns 13A, 13B, and 13C. The second substrate 14 is arranged above the first substrate 11 and the plurality of electrolytic capacitors 12 and substantially parallel to the first substrate 11. As shown in FIG. 2 , the first substrate 11 is housed and arranged near one side of the case 10, which is substantially rectangular in plan view, and the plurality of electrolytic capacitors 12 are housed and arranged near the other side of the case 10. Additionally, an upper cover (not shown) is attached to the top of the case 10, covering the first substrate 11, electrolytic capacitors 12, second substrate 14, etc.

[0023] The first substrate 11 is a printed wiring board (PWB) on which a plurality of electronic components including switching elements 15 are mounted. A plurality of switching elements 15 are combined together to form the main part of a power control circuit 16 together with the electrolytic capacitor 12. The power control circuit 16 performs ON / OFF operation by controlling the switching elements 15 using a control unit (not shown), thereby converting the DC power of the battery into three-phase AC power.

[0024] A pair of battery-side bus bars 17A, 17B, which are electrodes for supplying current to the battery, and three motor-side bus bars 18A, 18B, 18C, which are electrodes for supplying current to the motor, are connected to the power control circuit 16. The pair of battery-side bus bars 17A, 17B can be connected to the positive and negative poles of the battery via connection cables (not shown). The three motor-side bus bars 18A, 18B, 18C can be connected to the U-phase, V-phase, and W-phase power supply parts of the motor via connection cables (not shown).

[0025] As shown in FIG. 2 , the electrolytic capacitor 12 located near the other side of the case 10 is formed in a generally cylindrical shape. These electrolytic capacitors 12 are arranged in parallel in a direction perpendicular to the longitudinal direction (axial direction). The electrolytic capacitors 12 are connected to a circuit on the first substrate 11 via connection bus bars 19A and 19B surface-mounted on the first substrate 11. In this embodiment, the case 10, the first substrate 11 supported by the case 10, and the electrolytic capacitors 12 constitute the main part of the base block 20. Hereinafter, the direction along the longitudinal direction (axial direction) of the electrolytic capacitors 12 will be referred to as the X-direction. The direction in which the electrolytic capacitors 12 are arranged in parallel will be referred to as the Y-direction, and the direction perpendicular to the X-direction and Y-direction will be referred to as the Z-direction. Arrows indicating the X-direction, Y-direction, and Z-direction are indicated at appropriate locations in the drawings.

[0026] Positive and negative circuit terminals (not shown), which are power input sections from the battery, are mounted on the top surface of the first substrate 11. These circuit terminals are located near both ends in the Y direction of the first substrate 11. Battery-side bus bars 17A and 17B, which are electrodes for supplying current, are connected to the positive and negative circuit terminals on the first substrate 11, respectively.

[0027] Each battery-side busbar 17A, 17B is formed by bending a long, conductive metal plate longitudinally into a hat shape. One longitudinal end of each battery-side busbar 17A, 17B is a terminal fixing portion 17Aa, 17Ba attached to the upper surface of one end of the case 10 in the X direction, and the other longitudinal end is a circuit fixing portion 17Ab, 17Bb connected to the positive and negative circuit terminals on the first circuit board 11. Furthermore, the longitudinal center region of each battery-side busbar 17A, 17B is a bent portion 17Ac, 17Bc bent upward into a generally U-shape. The terminal fixing portions 17Aa, 17Ba and circuit fixing portions 17Ab, 17Bb of each battery-side busbar 17A, 17B are fixed to the case 10 and the first circuit board 11 so that the longitudinal direction of each battery-side busbar 17A, 17B is aligned with the X direction.

[0028] Three output circuit terminals (not shown) for the U-phase, V-phase, and W-phase, which are power output sections to the motor, are mounted on the top surface of the first substrate 11. These output circuit terminals are arranged in the central region of the first substrate in the Y direction, spaced approximately evenly apart in the Y direction. Motor bus bars 18A, 18B, and 18C, which are current-carrying electrodes, are connected to each of these output circuit terminals.

[0029] Like the battery-side bus bars 17A and 17B, the motor-side bus bars 18A, 18B, and 18C are formed by bending a long, conductive metal plate longitudinally into a hat shape. One longitudinal end of each motor-side bus bar 18A, 18B, and 18C is a terminal fixing portion 18Aa, 18Ba, and 18Ca that is attached to the upper surface of one end of the case 10 in the X direction, and the other longitudinal end is a circuit fixing portion 18Ab, 18Bb, and 18Cb that is connected to the respective output-side circuit terminals on the first board 11. The longitudinal center region of each motor-side bus bar 18A, 18B, and 18C is a bent portion 18Ac, 18Bc, and 18Cc that is bent upward into a generally U-shape. The motor-side bus bars 18A, 18B, 18C have terminal fixing portions 18Aa, 18Ba, 18Ca and circuit fixing portions 18Ab, 18Bb, 18Cb fixed to the case 10 and the first board 11 so that the longitudinal direction is along the X direction.

[0030] The three motor-side bus bars 18A, 18B, and 18C are arranged side by side in a row along the Y direction. The three motor-side bus bars 18A, 18B, and 18C are arranged at equal intervals in the Y direction. One battery-side bus bar 17A is arranged adjacent to one end of the three motor-side bus bars 18A, 18B, and 18C on the outer side in the arrangement direction, and the other battery-side bus bar 17B is arranged adjacent to the other end of the three motor-side bus bars 18A, 18B, and 18C on the outer side in the arrangement direction. Therefore, the pair of battery-side bus bars 17A and 17B and the three motor-side bus bars 18A, 18B, and 18C are arranged side by side in a row along the Y direction. The terminal fixing portions 17Aa, 17Ba, 18Aa, 18Ba, and 18Ca of the battery side bus bars 17A and 17B and the motor side bus bars 18A, 18B, and 18C are arranged in a row along the Y direction at one end of the case 10 in the X direction.

[0031] The second substrate 14 is a printed wiring board (PWB) on which electronic components are mounted. The circuits printed on the second substrate 14 are connected to the circuits on the first substrate 11 via inter-board connectors 21 (see FIG. 2). A signal connector 22 is held between the case 10 and an upper cover (not shown). A plurality of signal terminals protruding from the signal connector 22 are also connected to the circuits on the second substrate 14.

[0032] The second substrate 14 is formed in a substantially rectangular shape as shown in FIG. 1 . One edge of the second substrate 14 in the X direction is fixed to the case 10 (base block 20) ​​via a pair of support columns 13A protruding from the case 10. The pair of support columns 13A are spaced apart in the Y direction and each penetrates the second substrate 14 in the up-down direction. One edge of the second substrate 14 in the X direction rests on the upper surface of each support column 13A. In this state, the one edge of the second substrate 14 in the X direction is fastened to the upper end of each support column 13A by a fixing screw 45.

[0033] The other side of the second substrate 14 in the X direction is fixed to the case 10 via two pairs of support columns 13B, 13C that protrude from the case 10. The edge of the other side of the second substrate 14 in the X direction is placed on the upper surfaces of the pair of support columns 13C and, in this state, is fixed to the upper ends of the support columns 13C by fixing screws 46. In addition, another pair of support columns 13B penetrate the second substrate 14 in the vertical direction and, in this state, are fitted into fitting holes 23 of the second substrate 14.

[0034] Three Hall ICs 40, each incorporating a Hall element, are attached to the underside of the second substrate 14 near one side in the X direction (the end in the extension direction). Each Hall IC 40 is positioned below the second substrate 14, facing the bent portion 17Ac of one of the battery-side busbars 17A (e.g., the busbar on the positive pole side). This Hall IC 40 faces the upper surface of the bent portion 17Ac of the battery-side busbar 17A, with a small gap between them. When direct current from the battery flows through the battery-side busbar 17A, this Hall IC 40 detects the magnetic force generated by that current. The detection circuit calculates the value of the current flowing through the battery-side busbar 17A based on the detected magnetic force.

[0035] The other Hall IC 40 is disposed below the second substrate 14 so as to face the bent portion 18Ac of the motor-side bus bar 18A at one end in the arrangement direction. This Hall IC 40 faces the upper surface of the bent portion 18Ac of the motor-side bus bar 18A with a small gap between them. When an AC current flows from the power control circuit 16 to the motor-side bus bar 18A, this Hall IC 40 detects the magnetic force generated by the current. The detection circuit calculates the value of the current flowing through the motor-side bus bar 18A based on the detected magnetic force.

[0036] The remaining Hall IC 40 is disposed below the second substrate 14 so as to face the bent portion 18Cc of the motor-side bus bar 18C at the other end in the arrangement direction. This Hall IC 40 faces the upper surface of the bent portion 18Cc of the motor-side bus bar 18C with a small gap between them. When AC current flows from the power control circuit 16 to the motor-side bus bar 18C, this Hall IC 40 detects the magnetic force generated by the current. The detection circuit calculates the value of the current flowing through the motor-side bus bar 18C based on the detected magnetic force.

[0037] In this embodiment, a Hall IC 40 for detecting the current flowing through the central motor-side bus bar 18B is not provided. The current value of the current flowing through the central motor-side bus bar 18B is calculated based on the detected values ​​of the current flowing through the motor-side bus bars 18A and 18C on both sides. In addition, a magnetic shield member 50 made of permalloy or the like is attached around the bent portion 18Bc of the central motor-side bus bar 18B. This magnetic shield member 50 prevents the magnetic field caused by the current flowing through the central motor-side bus bar 18B from affecting the detection results of the Hall IC 40.

[0038] In this embodiment, the Hall IC 40 is used, in which the Hall element and the amplifier circuit are packaged. However, the Hall element and the amplifier circuit may be configured separately. In this case, at least the Hall element is disposed in proximity to the corresponding bus bar. Furthermore, the magnetic detection element is not limited to the Hall element. The magnetic detection element may be any other element that can detect a magnetic field caused by a current flowing through the corresponding bus bar (electrode).

[0039] Here, the installation portions of the three Hall ICs 40 are all arranged near support portions 14a of the support posts 13A on the edge (end in the extension direction) of the second substrate 14. In the present embodiment, the support portions 14a on the edge of the second substrate 14 are formed by portions that are sandwiched between the upper end surfaces of the support posts 13A and the heads of the fixing screws 45. The three Hall ICs 40 arranged on the edge of the second substrate 14 are arranged side by side in a row along the edge (along the Y direction).

[0040] The positional relationship of each support column 13A with respect to the bus bars is as follows: One support column 13A is disposed approximately midway between the motor-side bus bar 18A at one end in the arrangement direction and one of the battery-side bus bars 17A adjacent to that motor-side bus bar 18A. Therefore, the Hall IC 40 disposed facing the upper surface of the bent portion 18Ac of the motor-side bus bar 18A and the Hall IC 40 disposed facing the upper surface of the bent portion 17Ac of the battery-side bus bar 17A are approximately the same distance from the support portion 14a of one support column 13A.

[0041] The other support column 13A is disposed at a substantially midpoint between the motor-side bus bar 18C at the other end in the arrangement direction and the other battery-side bus bar 17B adjacent to the motor-side bus bar 18C. The distance from the Hall IC 40, which is disposed opposite the upper surface of the bent portion 18Cc of the motor-side bus bar 18C, to the support portion 14a of the other support column 13A is substantially equal to the distance from the Hall IC 40 on the motor-side bus bar 18A side to the support portion 14a of one support column 13A.

[0042] These distances (the distances from each support portion 14a to the nearest Hall IC 40) are set so that the vibration amplitude of the installation portion of the Hall IC 40 falls within an allowable range when external vibration is input. Here, the "allowable range" means that the magnetic field (current) detected by the Hall IC 40 falls within an allowable error range. In this embodiment, the external input vibration is assumed to be input vibration when the motor control device 1 is mounted on a vehicle.

[0043] Effect of the Embodiment As described above, in the motor control device 1 of this embodiment, the Hall IC 40 (magnetic detection element) is disposed near the support portion 14a formed by the support column 13A at the end in the extension direction of the second substrate 14. Therefore, in the motor control device 1 of this embodiment, even if there is external vibration input, fluctuations in the separation distance between the current-carrying electrodes (battery-side bus bar 17A and motor-side bus bars 18A, 18C) and the Hall IC 40 (magnetic detection element) can be suppressed.

[0044] That is, the amplitude of vibration in the central region of the second substrate 14 tends to increase when external vibration is input, but the end portions of the second substrate 14 in the extension direction supported by the support columns 13A do not vibrate with large amplitude even when external vibration is input. Therefore, the Hall IC 40 (magnetic detection element) disposed near the support portions 14a of the support columns 13A at the end portions of the second substrate 14 in the extension direction does not vibrate significantly when subjected to external vibration input. Therefore, the motor control device 1 of this embodiment can suppress fluctuations in the separation distance between the current-carrying electrodes (bus bars) and the Hall IC 40 (magnetic detection element) even when external vibration is input.

[0045] Therefore, when the motor control device of this embodiment is adopted, it is possible to stably improve the detection accuracy of the current flowing through the electrodes (bus bars), which makes it possible to contribute to Goal 7 of the Sustainable Development Goals (SDGs) led by the United Nations, which is to "Ensure access to affordable, reliable, sustainable and modern energy for all," and Goal 8, which is to "Promote sustained, inclusive and sustainable economic growth, full and productive employment and decent work for all."

[0046] Furthermore, in the motor control device 1 of this embodiment, the bus bars (battery-side bus bar 17A and motor-side bus bars 18A and 18C) that serve as electrodes for supplying current are provided with bent portions 17Ac, 18Ac, and 18Cc so as to be close to the Hall IC 40 on the second board 14 side. Therefore, even if the distance between the fixed portion of the bus bar and the second board 14 is large, the distance between the bus bar (electrode) that is the detection target and the Hall IC 40 can be sufficiently narrowed by bringing the bent portions 17Ac, 18Ac, and 18Cc on the bus bar close to the second board 14 side. Therefore, when this configuration is adopted, the detection accuracy of the Hall IC 40 can be further improved.

[0047] Furthermore, in the motor control device 1 of this embodiment, the multiple Hall ICs 40 are arranged side by side along one edge of the second substrate 14 in the extension direction, and this edge of the second substrate 14 is fixed to the case 10 (base block 20) ​​via the multiple support columns 13A. Therefore, the multiple Hall ICs 40 are arranged along one edge of the second substrate 14, whose rigidity is increased by the multiple support columns 13A. Therefore, when this configuration is adopted, it is possible to efficiently suppress fluctuations in the separation distance between the multiple Hall ICs 40 and the bus bars (battery-side bus bar 17A, motor-side bus bars 18A, 18C) facing them.

[0048] Furthermore, in the motor control device 1 of this embodiment, the battery-side bus bars 17A and 17B are disposed on the outer sides of the three horizontally arranged motor-side bus bars 18A, 18B, and 18C. Hall ICs 40 are disposed adjacent to one of the battery-side bus bars 17A and adjacent to each of the three motor-side bus bars 18A, 18B, and 18C on the outer side of the arrangement. Therefore, the input current from the battery can be detected by the Hall IC 40 disposed adjacent to one of the battery-side bus bars 17A. Two of the three-phase output currents from the motor can be detected by two Hall ICs 40 disposed adjacent to the two outermost motor-side bus bars 18A, 18B, and 18C in the arrangement. The remaining one-phase output current from the motor can be calculated based on the detection values ​​of the two Hall ICs 40 disposed adjacent to the two outermost motor-side bus bars 18A and 18C in the arrangement. Therefore, when the motor control device 1 having this configuration is adopted, the input current and the output current can be reliably detected using the minimum number of Hall ICs 40. This allows for a reduction in the size and weight of the current detection unit.

[0049] Furthermore, in the motor control device 1 of this embodiment, one support column 13A is disposed approximately midway between one motor-side bus bar 18A on the outer side in the arrangement direction and one battery-side bus bar 17A adjacent to the motor-side bus bar 18A. The other support column 13A is disposed approximately midway between another motor-side bus bar 18C on the outer side in the arrangement direction and the other battery-side bus bar 17B adjacent to the motor-side bus bar 18C. Therefore, the two support columns 13A supporting one edge of the second board 14 can efficiently suppress fluctuations in the Hall ICs 40 for detecting input current and the Hall ICs 40 for detecting output current. Therefore, when this configuration is adopted, the number of support columns 13A protruding from the base block 20 can be reduced while ensuring sufficient support rigidity for the second board 14, thereby further reducing the size and weight of the entire device.

[0050] The present invention is not limited to the above embodiment, and various design modifications are possible without departing from the spirit of the present invention. For example, in the above embodiment, the magnetic detection elements (Hall ICs 40) are arranged in positions facing the two motor-side bus bars 18A, 18C, respectively, but the magnetic detection elements (Hall ICs 40) may be arranged in positions facing the three motor-side bus bars 18A, 18B, 18C, respectively.

[0051] In addition, in the above embodiment, the power control circuit 16 is composed of the components mounted on the first substrate 11 and the electrolytic capacitor 12, but part of the power control circuit 16 may be provided on the second substrate 14.

[0052] In the above embodiment, the current-carrying electrodes are configured by bus bars, but the current-carrying electrodes are not limited to bus bars. The current-carrying electrodes may be, for example, linear or block-shaped, as long as they are capable of conducting current.

[0053] Furthermore, in the above embodiment, a pair of support pillars 13A are provided to support the end of the second substrate 14 (substrate) on the side where the Hall IC (magnetic detection element) is disposed, but the number of support pillars 13A is not limited to two. The number of support pillars 13A may be three or more, or may be one.

[0054] In the above embodiment, the Hall IC (magnetic detection element) is disposed only at one end (end in the X direction) of the second substrate 14 (substrate) in the extension direction, but the Hall IC (magnetic detection element) can also be disposed at the other end of the second substrate 14 (substrate) in the extension direction. In this case, the Hall IC (magnetic detection element) disposed at the other end of the second substrate 14 (substrate) in the extension direction may be disposed near a support portion supported by one of the support pillars.

[0055] In the above embodiment, the battery-side bus bars 17A and 17B and the motor-side bus bars 18A, 18B, and 18C are provided with bent portions 17Ac, 17Bc, 18Ac, 18Bc, and 18Cc, respectively. However, if each bus bar can be brought sufficiently close to the corresponding Hall IC (magnetic detection element), the bent portions 17Ac, 17Bc, 18Ac, 18Bc, and 18Cc are not necessarily provided.

[0056] DESCRIPTION OF SYMBOLS 1...motor control device, 10...case, 10a...fin, 11...first board, 12...electrolytic capacitor, 12...capacitor, 13A, 13B, 13C...support portion, 14...second board (board), 14a...support portion, 15...switching element, 16...power control circuit, 17A, 17B...battery side bus bar, 17Aa, 17Ba...terminal fixing portion, 17Ab, 17Bb...circuit fixing portion, 17Ac, 17Bc...flexion portion, 18A, 18B, 18C...motor side bus bars, 18Aa, 18Ba, 18Ca...terminal fixing portions, 18Ab, 18Bb, 18Cb...circuit fixing portions, 18Ac, 18Bc, 18Cc...bending portions, 19A, 19B...connection bus bars, 20...base block, 21...inter-board connector, 22...signal connector, 23...fitting hole, 40...Hall IC, 45, 46...fixing screws, 50...magnetic shielding member.

Claims

1. A motor control device comprising: a base block on which at least a part of a power control circuit is arranged; a support portion protruding from said base block; a circuit board fixed to said base block via said support portion; an electrode for supplying current connected to said power control circuit; and a magnetic detection element attached to a position on said circuit board close to said electrode and detecting a magnetic field caused by a current flowing through said electrode, wherein said magnetic detection element is arranged near a support portion provided by said support portion at an end of said circuit board in an extension direction.

2. The motor control device according to claim 1, characterized in that the electrodes are constituted by bus bars fixed to the base block, and a bent portion is provided on a part of the bus bar so as to be adjacent to the magnetic detection element.

3. A motor control device as described in claim 1 or 2, characterized in that a plurality of the electrodes are provided, a plurality of the magnetic detection elements are provided in a horizontal row along one edge of the substrate in the extension direction, and the one edge of the substrate is fixed to the base block via a plurality of the support portions.

4. The motor control device described in claim 3, characterized in that the electrodes comprise a pair of battery side bus bars connected to a battery and three motor side bus bars connected to a three-phase power supply unit of the motor, the battery side bus bars are each arranged on the outside of the three motor side bus bars arranged side by side in the arrangement direction, and the magnetic detection element is arranged at a position close to one of the battery side bus bars and a position close to each of the three motor side bus bars on the outside in the arrangement direction.

5. A motor control device as described in claim 4, characterized in that the support pillar portions are respectively arranged at approximately the midpoint between one motor side bus bar on the outside in the arrangement direction and one of the battery side bus bars adjacent to the motor side bus bar, and at approximately the midpoint between another motor side bus bar on the outside in the arrangement direction and the other battery side bus bar adjacent to the motor side bus bar.

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