Vehicle drive device

Abstract

The invention discloses a vehicle driving apparatus, comprising: a rotating electric machine; a plurality of modules which are disposed on one side in the axial direction of the rotating electrical machine, are disposed in an annular shape centered on the axis, and form an inverter device, the plurality of modules being provided in two or more for each phase; a plurality of bus bars connecting the plurality of modules and the rotating electrical machine and provided at least one for each of the plurality of phases; the current sensors are respectively arranged on the bus bars of each phase in the three phases; the plurality of modules constitute a single-phase module group by disposing a plurality of modules of the same phase adjacent to each other in the circumferential direction, and the bus bar and the current sensor for each phase are disposed in respective different inter-phase inter-module spaces among a plurality of inter-phase inter-module spaces, which are gaps in the circumferential direction of the plurality of single-phase module groups.

Description

Technical Field

[0001] The present disclosure relates to a vehicle drive device. Background Art

[0002] There is known a technique in which a plurality of modules forming an inverter device are arranged around the central axis of a rotating electrical machine when viewed from the axial direction.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Laid-Open No. 2020-025450 Summary of the Invention

[0006] Problems to be solved by the invention

[0007] However, in conventional technologies such as those described above, the current sensors that detect the current flowing through the busbars of each phase tend to be concentrated radially outward from the multiple modules and at a single location circumferentially around the axis (the circumference centered on the axis). This arrangement can easily reduce the reliability of sensor information from the current sensors due to interference from other phases.

[0008] Therefore, in one aspect, an object of the present disclosure is to improve the reliability of current sensors of respective phases in a structure in which a plurality of modules forming an inverter device are arranged in a ring shape centered on an axis.

[0009] Technical means to solve the problem

[0010] In one aspect, a vehicle driving device is provided, wherein:

[0011] have:

[0012] A rotary motor having a rotating shaft on a shaft;

[0013] a plurality of modules arranged on one axial side of the rotating electrical machine and arranged in a ring shape centered on the axis, and forming an inverter device for supplying multiple-phase AC power to the rotating electrical machine, wherein two or more of the plurality of modules are provided for each phase;

[0014] a plurality of bus bars connecting the plurality of modules and the rotating electrical machine, with at least one bus bar provided for each of the plurality of phases; and

[0015] a current sensor, disposed on the bus bar of each phase, generating an electrical signal corresponding to the current flowing in the bus bar;

[0016] The plurality of modules are arranged adjacent to each other in the circumferential direction to form a single-phase module group.

[0017] The busbars and the current sensors of each phase are arranged in different inter-phase module spaces among a plurality of inter-phase module spaces that are gaps in the circumferential direction of the plurality of single-phase module groups.

[0018] Effects of the Invention

[0019] In one aspect, according to the present disclosure, in a structure in which a plurality of modules forming an inverter device are arranged in a ring shape centered on an axis, the reliability of the current sensor of each phase can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of an example of an electric circuit including a rotating electrical machine according to this embodiment.

[0021] Figure 2 Schematic diagram of a vehicle drive system including the rotating electrical machine of this embodiment.

[0022] Figure 3A It is a cross-sectional view schematically showing the main part of the vehicle drive device of this embodiment.

[0023] Figure 3B It is a cross-sectional view schematically showing the main part of the vehicle drive device of this embodiment.

[0024] Figure 4 This is a perspective view of the motor drive device of this embodiment as viewed from the X1 side.

[0025] Figure 5 It is an explanatory diagram of each component of the motor drive device of this embodiment.

[0026] Figure 6 It is a three-dimensional diagram of a single output bus bar.

[0027] Figure 7 This is a plan view showing a portion axially outward of the rotating electrical machine 1 in the vehicle drive device of the present embodiment, as viewed in the axial direction.

[0028] Figure 8 It is from Figure 7 The figure shown is a top view that mainly retains the structural components of the electrical system and removes other components.

[0029] Figure 9 is Figure 7 This is a cross-sectional view of the vicinity of Q7 when cut along the XZ plane passing through the current sensor. DETAILED DESCRIPTION

[0030] The following describes various embodiments in detail with reference to the accompanying drawings. The dimensional ratios in the drawings are merely examples and are not intended to be limiting. For ease of explanation, shapes and other aspects of the drawings may be partially exaggerated. Furthermore, in the drawings, for ease of illustration, only some of the reference numerals may be used to designate multiple portions with the same attributes.

[0031] Hereinafter, after an overview of the electrical system (control system) of the vehicle drive device 10 of the present embodiment and the entire drive system including the vehicle drive device 10 of the present embodiment is given, the vehicle drive device 10 of the present embodiment will be described in detail.

[0032] [Electrical system of vehicle drive unit]

[0033] Figure 1 1 is a schematic diagram of an example of an electric circuit 200 including a rotating electrical machine 1. Figure 1 The control device 500 is also shown in FIG. Figure 1 In FIG. 5 , the dotted arrows corresponding to the control device 500 represent the exchange of information (signals or data).

[0034] The rotating electrical machine 1 is driven by the control of the inverter INV by the control device 500. Figure 1 In the illustrated circuit 200, a rotating electrical machine 1 is electrically connected to a power source Va via an inverter INV. Furthermore, the inverter INV includes power switching elements (e.g., MOSFETs or IGBTs) on the high-potential side P and low-potential side N of the power source Va, for each phase. The power switching elements on the high-potential side P and the low-potential side N form upper and lower arms. Furthermore, the inverter INV may include multiple sets of upper and lower arms for each phase. Each power switching element can be driven using PWM (Pulse Width Modulation) under the control of the control device 500 to generate a desired rotational torque. Alternatively, the power source Va may be a battery with a relatively high rated voltage, such as a lithium-ion battery or a fuel cell.

[0035] In this embodiment, if Figure 1 As shown in the circuit 200, a smoothing capacitor C is electrically connected in parallel with the inverter INV between the high potential side P and the low potential side N of the power supply Va. Alternatively, a plurality of smoothing capacitors C may be electrically connected in parallel between the high potential side P and the low potential side N of the power supply Va. Furthermore, a DC / DC converter may be provided between the power supply Va and the inverter INV.

[0036] [Overall drive system]

[0037] Figure 2 FIG. 1 is a schematic diagram of a vehicle drive system 100 including a rotating electrical machine 1. Figure 2 In FIG, an X direction, an X1 side, and an X2 side along the X direction are defined. The X direction is parallel to the direction of the first axis A1 (hereinafter also referred to as the "axial direction").

[0038] exist Figure 2 In the illustrated example, a vehicle drive system 100 includes a rotating electrical machine 1 serving as a drive source for wheels W, and a drive transmission mechanism 7 provided in a power transmission path connecting the rotating electrical machine 1 and the wheels W. The drive transmission mechanism 7 includes an input member 3, a counter gear mechanism 4, a differential gear mechanism 5, and left and right output members 61 and 62.

[0039] The input member 3 includes an input shaft 31 and an input gear 32. The input shaft 31 is a rotating member that rotates about the first axis A1. The input gear 32 is a gear that transmits the rotational torque (driving force) from the rotating electric machine 1 to the countershaft gear mechanism 4. The input gear 32 is connected to the input shaft 31 of the input member 3 so as to rotate integrally therewith.

[0040] The counter gear mechanism 4 is disposed on the power transmission path between the input member 3 and the differential gear mechanism 5. The counter gear mechanism 4 includes a counter shaft 41, a first counter gear 42, and a second counter gear 43.

[0041] The countershaft 41 is a rotating member that rotates about the second axis A2. The second axis A2 extends parallel to the first axis A1. The first countershaft gear 42 is the input member of the countershaft gear mechanism 4. The first countershaft gear 42 meshes with the input gear 32 of the input member 3. The first countershaft gear 42 is connected to the countershaft 41 so as to rotate integrally therewith.

[0042] The second counter gear 43 is an output member of the counter gear mechanism 4. In this embodiment, as an example, the second counter gear 43 is formed to have a smaller diameter than the first counter gear 42. The second counter gear 43 is connected to the counter shaft 41 so as to rotate integrally therewith.

[0043] The differential gear mechanism 5 is arranged on the third axis A3, which serves as its rotational axis. The third axis A3 extends parallel to the first axis A1. The differential gear mechanism 5 distributes the driving force transmitted from the rotating electric machine 1 to the left and right output members 61 and 62. The differential gear mechanism 5 includes a differential input gear 51, which meshes with the second countershaft gear 43 of the countershaft gear mechanism 4. In addition, the differential gear mechanism 5 includes a differential housing 52, which houses a pinion shaft, a pinion gear, and left and right side gears. The left and right side gears are respectively connected to the left and right output members 61 and 62 so as to rotate integrally with the left and right output members 61 and 62.

[0044] The left and right output members 61 and 62 are drivingly connected to the left and right wheels W. The left and right output members 61 and 62 transmit the driving force distributed by the differential gear mechanism 5 to the wheels W. The left and right output members 61 and 62 may be composed of two or more members.

[0045] In this manner, the rotating electric machine 1 drives the wheel W via the drive transmission mechanism 7. However, in other embodiments, the rotating electric machine 1 may be disposed within the wheel as an in-wheel motor. In this case, the vehicle drive system 100 may also be configured without the drive transmission mechanism 7. Furthermore, in other embodiments, a plurality of rotating electric machines 1 may be provided that share part or all of the drive transmission mechanism 7.

[0046] [Details of vehicle drive system]

[0047] Figure 3A as well as Figure 3B is a cross-sectional view of the main part of the vehicle drive device 10 of this embodiment, Figure 3A This is a cross-sectional view through oil passage 2530. Figure 3B It is a cross-sectional view through the cooling water channel 2528.

[0048] The vehicle drive device 10 includes the aforementioned rotating electrical machine 1 , a housing 2 , and a motor drive device 8 .

[0049] The vehicle drive device 10 is mounted on a vehicle as part of a vehicle drive system 100 and, as described above, generates driving force to move the vehicle forward or backward. The vehicle can be of any form, such as a four-wheeled car, a bus, a truck, a motorcycle, or construction machinery. Furthermore, the vehicle drive device 10 can also be mounted on the vehicle together with another drive source (e.g., an internal combustion engine).

[0050] The rotating electrical machine 1 includes a rotor 310 and a stator 320. Figure 3A as well as Figure 3B1 shows a portion of one axial end side (X1 side) of the rotating electrical machine 1. The rotating electrical machine 1 is an inner rotor type, and the stator 320 is provided around the radially outer side of the rotor 310. That is, the rotor 310 is arranged radially inside the stator 320.

[0051] The rotor 310 includes a rotor core 312 and a shaft 314 .

[0052] Rotor core 312 can be made of, for example, annular magnetic laminated steel plates. Permanent magnets 325 can be embedded within rotor core 312. Alternatively, permanent magnets 325 can be attached to the outer circumference of rotor core 312. The arrangement of permanent magnets 325 is arbitrary. Rotor core 312 is fixed to the outer circumference of shaft portion 314 and rotates integrally with shaft portion 314.

[0053] The shaft portion 314 is arranged on the first axis A1 and defines the rotating axis of the rotating electrical machine 1. The shaft portion 314 is rotatably supported by the cover member 252 (described later) of the housing 2 via a bearing 240 on the X1 side of the portion where the rotor core 312 is fixed. Furthermore, the shaft portion 314 is rotatably supported by the housing 2 on the other axial end (the X2 side) of the rotating electrical machine 1 via a bearing corresponding to the bearing 240. This allows the shaft portion 314 to be rotatably supported by the housing 2 at both axial ends.

[0054] The shaft portion 314 is, for example, in the form of a hollow tube, having a hollow interior 314A. The hollow interior 314A may extend the entire axial length of the shaft portion 314. The hollow interior 314A can function as an axial oil passage. In this case, the shaft portion 314 may be formed with oil holes for discharging oil toward the coil ends 322A of the stator 320 and the like.

[0055] The stator 320 includes a stator core 321 and a stator coil 322 .

[0056] The stator core 321 may be formed of, for example, an annular magnetic laminated steel plate. The stator core 321 has radially-formed teeth (not shown) protruding radially inwardly on its inner periphery.

[0057] The stator coil 322 can be, for example, a conductor with a rectangular or circular cross-section and an insulating coating. The stator coil 322 is wound around the teeth (not shown) of the stator core 321. Furthermore, the stator coils 322 can be electrically connected in parallel, for example, using a Y-connection or a Δ-connection.

[0058] The stator coil 322 has coil ends 322A, which protrude axially outward from the slots of the stator core 321. In the following description, unless otherwise specified, coil ends 322A are referred to as portions of the stator coil 322, specifically the portions extending circumferentially on both axial sides of the stator core 321, extending along one axial end (the X1 side) serving as the lead wire.

[0059] The housing 2 can be formed of aluminum or the like. The housing 2 can be formed of casting or the like. The housing 2 includes a motor housing 250 and a cover member 252. The housing 2 accommodates the rotating electrical machine 1 and the motor drive device 8. Figure 2 In the case of the vehicle drive system 100 shown in FIG. Figure 2 As schematically shown, the housing 2 may also accommodate a drive transmission mechanism 7 .

[0060] The motor housing 250 forms a motor housing chamber SP1 that accommodates the rotating electric machine 1. Furthermore, the motor housing chamber SP1 may be an oil-tight space containing oil for cooling and / or lubricating the rotating electric machine 1 (and / or the drive transmission mechanism 7). The motor housing 250 has a peripheral wall portion that surrounds the radially outer side of the rotating electric machine 1. The motor housing 250 may also be implemented by combining multiple components. Furthermore, the motor housing 250 may be integrated with another housing component that accommodates the drive transmission mechanism 7 on the other axial end side (the X2 side).

[0061] The cover member 252 is formed from a material with high thermal conductivity (e.g., aluminum). It is bonded to one axial end (X1 side) of the motor housing 250. The cover member 252 serves as a lid that covers the one axial end (X1 side) of the motor housing chamber SP1 and faces the rotating electrical machine 1 in the axial direction. In this case, the cover member 252 may completely or substantially completely close the opening on the one axial end (X1 side) of the motor housing 250.

[0062] Cover member 252 forms inverter accommodation chamber SP2 that accommodates motor drive device 8. Alternatively, motor case 250 may form part of inverter accommodation chamber SP2, or cover member 252 may form part of motor accommodation chamber SP1.

[0063] The cover member 252 supports the motor drive device 8. For example, the motor drive device 8 may be mounted on the cover member 252 in a module configuration as described below. This allows the cover member 252 to be joined to the motor housing 250 after a portion or the entirety of the motor drive device 8 is mounted on the cover member 252, thereby improving the ease of assembly of the motor drive device 8.

[0064] Bearing 240 is provided on cover member 252 to rotatably support rotor 310. Specifically, cover member 252 includes bearing support portion 2524 that supports bearing 240. Bearing support portion 2524 refers to the entire portion of cover member 252 where bearing 240 is provided in the axial direction.

[0065] like Figure 3A as well as Figure 3B As shown, bearing 240 is disposed radially outwardly at the X1-side end of shaft portion 314. Specifically, the radially outer side of the outer ring of bearing 240 is supported by cover member 252, while the radially inner side of the inner ring is supported by the outer circumferential surface of shaft portion 314. In a modified example, the reverse arrangement may be employed, in which the radially inner side of the inner ring of bearing 240 is supported by cover member 252, while the radially outer side of the outer ring is supported by the inner circumferential surface of shaft portion 314.

[0066] like Figure 3A as well as Figure 3B As shown, the cover member 252 includes a circular bottom portion 2521 centered on the first axis A1, and a peripheral wall portion 2522 that projects from the outer periphery of the bottom portion 2521 toward the other axial end (the X2 side). The bottom portion 2521 and the peripheral wall portion 2522 define the inverter housing chamber SP2. A bearing support portion 2524 is provided in the center portion (the portion centered on the first axis A1) of the bottom portion 2521 on the other axial end (the X2 side).

[0067] The inverter storage chamber SP2 may be a space, but is preferably sealed by a resin containing a filler having high thermal conductivity. That is, the cover member 252 preferably has a molded resin portion 2523 having thermal conductivity. In this case, the molded resin portion 2523 can have the following functions: sealing and supporting the motor drive device 8 described later; protecting the motor drive device 8 from the oil in the motor storage chamber SP1; and transferring heat from the motor drive device 8 to the cover member 252. In addition, Figure 3A as well as Figure 3B In FIG, a portion of the components (inverter module 90 described later, etc.) sealed in the molded resin portion 2523 is shown in perspective. The range of formation of the molded resin portion 2523 is not limited to Figure 3A The range shown in the figure may extend from the bottom 2521 side to the X1 side, or may extend to the X2 side.

[0068] Here, refer to Figure 3A as well as Figure 3BAn example of a cooling structure that can be applied to this embodiment is described. Hereinafter, the terms radial, axial, and circumferential refer to directions relative to the first axis A1 unless otherwise specified. That is, the axial direction is a direction parallel to the first axis A1 (including a direction along a line coaxial with the first axis A1), the radial direction is a direction passing through the first axis A1 and orthogonal to the first axis A1, and the circumferential direction is a direction around the first axis A1 within any plane orthogonal to the first axis A1. In addition, "around the axis" refers to the direction around the first axis A1.

[0069] exist Figure 3A as well as Figure 3B In the example shown, the cooling structure includes: a cooling water passage 2528 and an oil passage 2530 (hereinafter referred to as "the cover oil passage 2530") respectively formed in the cover member 252, a hollow interior 314A forming an axial oil passage, a tubular member 180 for axial supply of oil to the hollow interior 314A, and a tubular member 181 forming an upper hanging oil passage.

[0070] Cooling water flows through cooling water channel 2528. Alternatively, the cooling water may contain LLC (Long Life Coolant). In this case, the cooling water flowing through cooling water channel 2528 dissipates heat through a radiator (not shown) mounted on the vehicle, maintaining a relatively low temperature.

[0071] The cooling water channel 2528 can have any shape when viewed in the axial direction, for example, a circular shape, a spiral shape, or a shape that meanders radially outward and inward and extends circumferentially. Furthermore, when the cover member 252 is manufactured using a core, etc., the shape of the cooling water channel 2528 can be more freely selected.

[0072] Oil flows through the cover oil passage 2530. Oil is supplied from an oil pump (not shown) to the cover oil passage 2530. The oil pump may be a mechanical type linked to the drive transmission mechanism 7 or an electric type, for example.

[0073] The cover oil passage 2530 may overlap with the cooling water passage 2528 when viewed in the radial direction. In this case, compared to a case where the cover oil passage 2530 and the cooling water passage 2528 do not overlap when viewed, the thickness of the cover member 252 (the thickness of the bottom portion 2521 in the axial direction) can be reduced, thereby reducing the axial volume of the vehicle drive device 10.

[0074] The oil supplied to the cover oil passage 2530 is supplied to the tubular member 180 after passing through the cover oil passage 2530. The tubular member 180 is a hollow tubular shape with a flow path formed inside. The tubular member 180 can extend axially concentrically with the first axis A1 and has both ends of the axial direction open. Figure 3AAs shown, the tubular member 180 is connected to the cover oil passage 2530 (the outlet portion 25302 on the axial side) on the X1 side, extends axially into the hollow interior 314A on the X2 side, and the opening at the end on the X2 side communicates with the hollow interior 314A.

[0075] The oil supplied to tubular member 180 is supplied to the axial oil passage (hollow interior 314A). The oil supplied to hollow interior 314A flows along the inner circumference of shaft portion 314 due to the centrifugal force of rotor 310's rotation, cooling rotor core 312 and its associated permanent magnets 325 from the radially inner side. Alternatively, radial oil holes may be formed in shaft portion 314 to spray oil from the radially inner side toward coil end 322A (the same applies to coil end 322A on the X2 side (not shown), and the same applies hereinafter). In this case, coil end 322A can be cooled from the radially inner side.

[0076] The oil supplied to the cover oil passage 2530 passes through the cover oil passage 2530 and is then supplied to the tubular member 181. The tubular member 181 is a hollow tubular structure with a flow path formed therein. The tubular member 181 may extend axially outward from the stator 320 in the radial direction when viewed in the axial direction and may be open at both ends in the axial direction.

[0077] The oil supplied to the tubular member 181 falls onto the stator 320 due to gravity through the radial oil holes 1810 formed in the tubular member 181. The oil that has fallen onto the stator 320 flows downward along the outer peripheral surface of the stator 320. This allows the stator 320 to be cooled from the radial outside.

[0078] The oil holes 1810 of the tubular member 181 may include, for example, an oil hole 1810A that faces the coil end portion 322A in the radial direction.

[0079] Furthermore, the oil holes 1810 of the tubular member 181 may include oil holes 1810B that radially face the outer peripheral surface of the stator core 321. This allows the stator core 321 (and the stator coil 322) to be cooled from the radially outer side.

[0080] In addition, as an example, refer to Figure 3A as well as Figure 3B While a specific cooling structure will be described, the details of the cooling structure are arbitrary. For example, the tubular member 180 and / or the tubular member 181 may be omitted. Alternatively, the oil cooling itself may be omitted.

[0081] In this embodiment, the motor drive device 8 includes a power module 80 , a capacitor module 82 , a control substrate 84 , and a wiring portion 88 .

[0082] Figure 4This is a perspective view of the motor drive device 8 of this embodiment as viewed from the X1 side. Figure 5 It is an explanatory diagram of each component of the motor drive device 8 of this embodiment. Figure 6 It is a three-dimensional diagram of the output bus bar 887 in a single state. Figure 7 1 is a plan view showing a portion of the vehicle drive device 10 of the present embodiment that is closer to the X1 side (negative side in the X direction) than the rotating electrical machine 1, as viewed in the axial direction. Figure 4 as well as Figure 5 In FIG, the control substrate 84 and a part of the wiring portion 88 are omitted. Figure 4 The three axes (X axis, Y axis, Z axis) that are orthogonal to each other in the right-hand coordinate system are shown in FIG. Figure 2 The X-axis is defined in the same way as in

[15] , Figure 4 The negative side of the x-axis of the three-axis markings corresponds to Figure 2 The X1 side of the X axis defined in [1].

[0083] In this embodiment, the power modules 80 and the capacitor modules 82 form a plurality of groups ( Figure 4 as well as Figure 5 In the illustrated example, twelve sets are used) and are arranged circumferentially. The number of power modules 80 and capacitor modules 82 sets can vary depending on the specifications of the rotating electrical machine 1. Basically, increasing the number of power modules 80 and capacitor modules 82 sets increases the output of the rotating electrical machine 1. Therefore, when designing the rotating electrical machine 1, multiple variations can be set, varying the number of power modules 80 and capacitor modules 82 sets (and the associated output of the rotating electrical machine 1).

[0084] The power modules 80 and the capacitor modules 82 are arranged in a ring shape around the axis for each group. The power modules 80 and the capacitor modules 82 are preferably arranged in a circumferential direction so that the same phases are adjacent to each other to form a single-phase module group. That is, each group of the power modules 80 and the capacitor modules 82 is formed into a single-phase module group by being assembled for each phase, and is dispersedly arranged in a ring shape around the axis. In this case, the power modules 80 and the capacitor modules 82 can also be arranged at equal intervals, for example. In the example shown in the figure, the number of groups of power modules 80 and capacitor modules 82 is 12, and the 12 groups are arranged at 30-degree intervals. As a result, the temperature distribution along the circumferential direction caused by the heat from the power modules 80 and the capacitor modules 82 can be made uniform.

[0085] However, in this embodiment, as a more preferred example, each group of power modules 80 and capacitor modules 82 is arranged so that the circumferential gap distance between the single-phase module groups (hereinafter referred to as "inter-phase module distance Δ1") is relatively wide. That is, in this embodiment, the inter-phase module distance Δ1 is significantly longer than the circumferential spacing Δ2 between each group of power modules 80 and capacitor modules 82 within the same phase (hereinafter referred to as "intra-phase module distance Δ2"). In this case, utilizing the relatively wide inter-phase module distance Δ1 allows for the optimal placement of the current sensor 9, the formation of the cooling water path 2528, and other aspects, as described later. Furthermore, the intra-phase module distance Δ2 can be the same (constant) for each phase.

[0086] Hereinafter, the inter-phase module distance Δ1 between the sets of power modules 80 and capacitor modules 82 for each phase will be referred to as "inter-phase module space S10" in the circumferential direction. Furthermore, since there are three sets of power modules 80 and capacitor modules 82 for each phase, grouped according to the three phases, three inter-phase module spaces S10 are formed at 120-degree intervals in the circumferential direction.

[0087] The power modules 80 and capacitor modules 82 are preferably in the form of an integrated assembly in each of a plurality of groups. In other words, each group of power modules 80 and capacitor modules 82 forms an integrated inverter module 90 .

[0088] In each of the inverter modules 90, the power module 80 has the same structure, and the capacitor module 82 has the same structure (electrical characteristics and shape, etc.). As a result, each inverter module 90 can also be replaced or repaired, which can improve versatility. In the present embodiment, in each of the inverter modules 90, the power module 80 includes a submodule 800 and a heat dissipation component 810. In this case, in each of the inverter modules 90, the submodule 800 has the same structure (electrical characteristics and shape, etc.), and the heat dissipation component 810 has the same structure (material or shape, etc.). As a result, when a plurality of inverter modules 90 are arranged circumferentially, there is no need to consider which inverter module 90 is arranged at which circumferential position, and the assembly is good.

[0089] In addition, in this embodiment, as described above, the four inverter modules 90 for the U phase among the 12 inverter modules 90 are arranged adjacent to each other in the circumferential direction as a group, the four inverter modules 90 for the V phase are arranged adjacent to each other in the circumferential direction as a group, and the four inverter modules 90 for the W phase are arranged adjacent to each other in the circumferential direction as a group.

[0090] Each of the submodules 800 forms an inverter INV (see Figure 1) form the upper and lower arms of one phase in the 12 power modules. This allows for sub-moduleization of each upper and lower arm, improving wiring efficiency. Specifically, in four of the 12 power modules 80, each sub-module 800 forms the upper and lower arms of the U phase. In the other four power modules 80, each sub-module 800 forms the upper and lower arms of the V phase. In the remaining four power modules 80, each sub-module 800 forms the upper and lower arms of the W phase.

[0091] Furthermore, in each inverter module 90, the submodule 800 includes a pair of power semiconductor chips 801 and 802. Specifically, the pair of power semiconductor chips 801 and 802 consists of a power semiconductor chip 801 forming an upper arm on the high potential side P and a power semiconductor chip 802 forming a lower arm on the low potential side N. Each of the power semiconductor chips 801 and 802 includes the power switching element described above.

[0092] like Figure 5 As shown, the power semiconductor chips 801 and 802 are preferably integrated with a heat dissipation member 810. Thus, the power module 80 integrally includes the heat dissipation member 810, and heat from the pair of power semiconductor chips 801 and 802 can be effectively dissipated via the heat dissipation member 810. Furthermore, compared to a case where the pair of power semiconductor chips 801 and 802 and the heat dissipation member 810 are separately assembled to the lid member 252 or the capacitor module 82, assembly efficiency can be improved.

[0093] In addition, if Figure 5 As shown, the power semiconductor chip 801 and the power semiconductor chip 802 are provided with bus bars 881, 882, 883, and 884 together with the resin molded portion 805 as part of the wiring portion 88. The bus bar 881 integrated with the power semiconductor chip 801 connects the power semiconductor chip 801 and the capacitor module 82 (e.g. Figure 5 The bus bar 883 integrated with the power semiconductor chip 801 electrically connects the power semiconductor chip 801 to the stator coil 322 of the corresponding phase in the rotating electrical machine 1. Similarly, the bus bar 882 integrated with the power semiconductor chip 802 electrically connects the power semiconductor chip 802 to the capacitor module 82 (e.g., Figure 5 The bus bar 884 integrated with the power semiconductor chip 802 electrically connects the power semiconductor chip 802 and the stator coil 322 of the corresponding phase in the rotating electrical machine 1. In this embodiment, the bus bar 883 and the bus bar 884 are connected to the output bus bar 887 (see FIG. 1 ) via the connecting bus bar 885. Figure 4 as well as Figure 6 The other end of the output bus bar 887 is electrically connected to the stator coil 322 of the corresponding phase in the rotating electrical machine 1.

[0094] In this embodiment, a pair of power semiconductor chips 801 and 802 are bonded to the circumferential side surfaces of the heat dissipation component 810. At this time, the power semiconductor chip 801 is bonded to the side surface (surface) on one circumferential side of the heat dissipation component 810, and the power semiconductor chip 802 is bonded to the side surface (surface) on the other circumferential side of the heat dissipation component 810. In addition, the bonding method is arbitrary, and an adhesive material with higher thermal conductivity may also be used. Thus, the heat dissipation component 810 can be effectively heated from the pair of power semiconductor chips 801 and 802 via the circumferential side surfaces. In addition, the space between the circumferentially adjacent heat dissipation components 810 can be effectively utilized to configure a pair of power semiconductor chips 801 and 802.

[0095] The heat dissipation member 810 is formed of a material having high thermal conductivity (eg, aluminum) and has the function of efficiently receiving heat from the submodule 800 and efficiently transferring the received heat to the cover member 252 (and the cooling water in the cooling water path 2528 ).

[0096] like Figure 4 as well as Figure 5 As shown, the heat dissipation member 810 preferably has a circumferential width that decreases radially inward when viewed axially. That is, in the heat dissipation member 810, the distance L1 between the circumferential side surfaces where the pair of power semiconductor chips 801 and 802 are bonded is preferably smaller on the side radially closer to the first axis A1 than on the side farther from the first axis A1. Thus, even when the heat dissipation member 810 is positioned radially inward of the capacitor module 82 and the number of power module 80 and capacitor module 82 groups (i.e., the number of inverter modules 90) is relatively large, the layout of the heat dissipation member 810 can be easily established.

[0097] Furthermore, a flow channel communicating with the cooling water channel 2528 may be formed in the heat dissipating member 810. Alternatively, the heat dissipating member 810 may be hollow, with a tubular member communicating with the cooling water channel 2528 passing through the interior.

[0098] The capacitor module 82 forms a smoothing capacitor C (see Figure 1 ) module. The capacitor module 82 may be a capacitor bus bar 821, 822 in which the capacitor element or wiring portion 88 forming the smoothing capacitor C is sealed with resin. In addition, the end portions of the capacitor bus bars 821, 822 exposed from the sealing resin portion form the high potential side terminal of the capacitor element and the low potential side terminal of the capacitor element, respectively. The capacitor bus bars 821, 822 are connected to the submodule 800 and are connected to the power supply bus bar 886 (see Figure 3A as well as Figure 3B )connect.

[0099] In each of the inverter modules 90, the capacitor module 82 is formed by electrically connecting the smoothing capacitor C in parallel between the high potential side P and the low potential side N of the submodule 800 of the corresponding group (see Figure 1 ).

[0100] In this embodiment, the capacitor module 82 is arranged radially outside the power module 80. This allows for a wider circumferential range of arrangement compared to arrangements radially inside the power module 80, making it easier to increase the volume of the capacitor module 82. For example, even when a large number of power modules 80 and capacitor modules 82 are used, a larger capacitor module 82 can be achieved. Consequently, it is easier to cope with increased output of the rotating electrical machine 1.

[0101] In addition, in this embodiment, Figure 3A as well as Figure 3B As shown, the axial extension of capacitor module 82 overlaps with the axial extension of power module 80. In particular, in this embodiment, submodule 800 of power module 80 overlaps with capacitor module 82 when viewed in the radial direction. This minimizes the axial volume of vehicle drive device 10 and allows capacitor module 82 and submodule 800 to be arranged axially between cover member 252 and rotating electric machine 1.

[0102] The control substrate 84 forms the control device 500 (see Figure 1 ) part or the whole. The control substrate 84 may also be formed of a multilayer printed circuit board, for example. The control substrate 84 may be fixed to the cover member 252. The control substrate 84 is arranged in an axial direction relative to the normal direction of the substrate surface. Thus, the control substrate 84 can be arranged using a small gap in the axial direction. For example, in this embodiment, Figure 3A as well as Figure 3B As shown, the control substrate 84 can be arranged axially between the rotating electrical machine 1 and the power module 80. In more detail, the control substrate 84 can be arranged axially between the coil end 322A of the rotating electrical machine 1 and the power module 80. Thus, an efficient arrangement can be achieved by utilizing a space that is prone to becoming a dead zone. In addition, the control substrate 84 can extend radially outward to a radial position overlapping with the coil end 322A when viewed axially, thereby maximizing the area of ​​the control substrate 84 (circuit portion formation range). In addition, an external ECU (Electronic Control Unit) or the like can be connected via the connector CN (refer to Figure 7 ) is connected to the control substrate 84.

[0103] The wiring portion 88 includes the capacitor bus bars 821 and 822, the bus bars 881, 882, 883, and 884, and the power supply bus bar 886 (see FIG. Figure 3A etc.) and output bus 887.

[0104] The power bus bar 886 can be, for example, annular and extend about the first axis A1. In this embodiment, the power bus bar 886 extends circumferentially between the cover member 252 and the submodule 800 in the axial direction, adjacent to the submodule 800 from the X1 side. This allows the cover member 252 (and the cooling water within the cooling water channel 2528) to be effectively cooled.

[0105] like Figure 7 As shown, the portion 8861 of the power bus bar 886 for connecting to the power connector CN0 on the power supply side may extend radially. In this case, the portion 8861 extends radially through the inter-phase module space S10 (i.e., between the sets of inverter modules 90 for each phase).

[0106] The output bus bar 887 is provided for each phase. The output bus bar 887 is a bus bar that connects each power module 80 and the rotating electrical machine 1. Figure 6 As shown, the output bus bar 887 includes an arc-shaped portion 8871 , a straight-line portion 8872 , and a lead-out portion 8873 .

[0107] For example, Figure 4 As shown, the arc-shaped portion 8871 of the output bus bar 887 can be arranged around the axis on the radial inner side of each inverter module 90. In this case, the output bus bar 887 of one phase extends to a circumferential range corresponding to the circumferential extension range of the set of inverter modules 90 of that phase (thus, a circumferential range of approximately 120 degrees). In this way, the arc-shaped portions 8871 of the three output bus bars 887 are arranged in a circular ring shape around the axis in a manner that does not overlap with each other in the circumferential direction. In this case, the arc-shaped portion 8871 of the output bus bar 887 abuts the above-mentioned connection bus bar 885 in the radial direction on the radial inner side of each inverter module 90, thereby being able to be electrically connected to the power module 80 of the corresponding inverter module 90.

[0108] In addition, the linear portion 8872 of the output bus bar 887 extends radially through the inter-phase module space S10 (i.e., between the sets of inverter modules 90 of each phase). In addition, as described above, the inter-phase module space S10 can be three, so that Figure 8 As shown, the linear portions 8872 of the three output bus bars 887 can extend radially through any of the three inter-phase module spaces S10 one by one.

[0109] With this configuration, the arc-shaped portion 8871 and the linear portion 8872 of the output bus bar 887 for each phase can have the same shape, thereby achieving cost reduction by commonalizing components.

[0110] In addition, although Figure 4 Although not shown in the figures, the radially outer ends of the linear portions 8872 of the output busbars 887 of each phase are electrically connected to the stator coils 322 of the corresponding phase in the rotating electrical machine 1 via lead portions 8873. In this case, the lead portions 8873 can have the same shape for each phase. In this case, the output busbars 887 of each phase can have the same shape as a single component for each phase, thereby achieving cost reductions due to the commonality of components.

[0111] Next, refer to Figure 8 A preferred arrangement of the current sensor 9 will be described later.

[0112] Figure 8 It is from Figure 7 The figure shown is a top view that mainly retains the structural components of the electrical system and removes other components. Figure 9 is Figure 7 The vicinity of the Q7 portion is a cross-sectional view when the current sensor 9 is cut along an XZ plane passing through the current sensor 9.

[0113] The current sensor 9 is provided for each phase. The current sensor 9 generates an electrical signal corresponding to the current flowing in the output bus bar 887 of each phase. In addition, the current sensor 9 may be a coreless type having no magnetic core, or may not be. In addition, the current sensor 9 may be fixed to the control substrate 84 (in Figure 9 In this case, the sensor information from the current sensor 9 can be easily transmitted using printed wiring on the control substrate 84.

[0114] The current sensor 9 is disposed in the inter-phase module space S10 (i.e., between the sets of inverter modules 90 for each phase) similarly to the linear portion 8872 of the output bus bar 887. In this case, the current sensor 9 for each phase is disposed one by one in any of the three inter-phase module spaces S10.

[0115] Thus, in this embodiment, a pair of output busbars 887 and current sensors 9 for each phase are arranged in each of the three inter-phase module spaces S10. This allows for efficient placement of current sensors 9 that utilize the inter-phase module spaces S10. Furthermore, since the inter-phase module spaces S10 are arranged 120 degrees apart circumferentially, the current sensors 9 for each phase are arranged 120 degrees apart around the axis. This allows the current sensors 9 and output busbars 887 for each phase to be circumferentially separated from each other. As a result, it is possible to prevent problems that could occur if the current sensors 9 for each phase were concentrated in the same circumferential range (i.e., reduced reliability of sensor information from the current sensors 9 due to interference from other phases). Furthermore, it is possible to reduce problems that could occur if the output busbars 887 for each phase were arranged close together circumferentially (e.g., ensuring space to ensure electrical insulation).

[0116] In this embodiment, each current sensor 9 is preferably positioned radially so as to overlap with the capacitor module 82 (smoothing capacitor C) in the circumferential direction around the axis. That is, the radial extension of the current sensor 9 overlaps with the radial extension of the capacitor module 82. This reduces the effect of the power module 80 on each current sensor 9, compared to a case where each current sensor 9 is positioned radially overlapping with the power module 80 (not shown). In other words, each current sensor 9 can be positioned less susceptible to switching noise, etc., from the power module 80. Based on this perspective, each current sensor 9 can be positioned in the inter-phase module space S10 so that its entirety is radially outward of the outermost diameter of the power module 80 and radially inward of the outermost diameter of the capacitor module 82.

[0117] In addition, in this embodiment, Figure 9 As shown, at least one of the three current sensors 9 preferably overlaps with the cooling water channel 2528 when viewed axially. Thus, the current sensor 9 overlapping with the cooling water channel 2528 when viewed axially can be cooled by the cooling water in the cooling water channel 2528. In addition, the output bus 887 of the three-phase output bus 887 provided with the current sensor 9 overlapping with the cooling water channel 2528 can be cooled by the cooling water in the cooling water channel 2528. In this case, Figure 9 As shown, the water channel portion of the cooling water channel 2528 that overlaps with the current sensor 9 may extend further toward the positive side in the Y direction than the other water channel portions. In this case, the current sensor 9 and the output bus bar 887 can be cooled effectively.

[0118] Furthermore, when viewed axially, the water channel portion of the cooling water channel 2528 that overlaps with the current sensor 9 may intersect the inter-phase module space S10 in the circumferential direction, or may extend radially in the same manner as the inter-phase module space S10. In either case, the cooling water in the water channel portion of the cooling water channel 2528 that overlaps with the current sensor 9 can be used to effectively cool the current sensor 9 and the portion 8861 of the power bus bar 886. Figure 9 In the example shown, the current sensor 9 is attached to the cover member 252 via the portion 8861 of the power bus bar 886. In this case, the power bus bar 886, which is more likely to heat up, can be cooled preferentially over the current sensor 9.

[0119] Although each embodiment has been described in detail above, the present invention is not limited to the specific embodiment and various modifications and changes can be made within the scope of the claims. In addition, all or a plurality of the structural components of the above-mentioned embodiments may be combined.

[0120] For example, in the above-described embodiment, the cooling water channel 2528 is formed in the cover member 252, but part or all of the cooling water channel 2528 may be formed in a member different from the cover member 252. For example, part or all of the cooling water channel 2528 may extend into the motor housing 250 or may be formed by a tubular conduit.

[0121] Description of reference numerals:

[0122] 10: Vehicle drive device, 1: Rotating electric machine, 887: Output bus bar (bus bar), 9: Current sensor, 90: Inverter module (inverter device, module), 252: Cover member (water channel forming member), 2528: Cooling water channel, 801, 802: Power semiconductor chip (power switching element), C: Smoothing capacitor, A1: First shaft (shaft)

Claims

1. A vehicle drive device, wherein: have: A rotary motor having a rotating shaft on a shaft; a plurality of modules arranged on one axial side of the rotating electrical machine and arranged in a ring shape centered on the axis, and forming an inverter device for supplying multiple-phase AC power to the rotating electrical machine, wherein two or more of the plurality of modules are provided for each phase; a plurality of bus bars connecting the plurality of modules and the rotating electrical machine, with at least one bus bar provided for each of the plurality of phases; as well as a current sensor, disposed on the bus bar of each phase, generating an electrical signal corresponding to the current flowing in the bus bar; The plurality of modules are arranged adjacent to each other in the circumferential direction to form a single-phase module group. The busbars and the current sensors of each phase are arranged in different inter-phase module spaces among a plurality of inter-phase module spaces that are gaps in the circumferential direction of the plurality of single-phase module groups.

2. The vehicle drive device according to claim 1, wherein: Each of the plurality of modules includes a power switching element and a smoothing capacitor, wherein the power switching element is located radially inside the smoothing capacitor. The current sensor for each phase is arranged at a radial position overlapping with the smoothing capacitor.

3. The vehicle drive device according to claim 1 or 2, wherein: Regarding the distance in the circumferential direction centered on the axis, the distance of the inter-phase module space is longer than the inter-module distance within the same phase.

4. The vehicle driving device according to claim 3, wherein: The vehicle drive device further includes a water channel forming member forming a cooling water channel through which cooling water flows. The cooling water channel extends radially through a circumferential range overlapping one of the plurality of inter-phase module spaces when viewed in the axial direction.

5. The vehicle driving device according to claim 4, wherein: When viewed in the axial direction, the current sensor of one phase overlaps with the cooling water channel.

6. The vehicle driving device according to claim 3, wherein: The busbars of each phase extend radially inwardly of the plurality of modules along a circumferential direction centered on the axis.

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