Vehicle Drive Unit

Abstract

Disclosed is a vehicle drive device including a rotating electrical machine having a rotor and a stator, an accommodating member forming an accommodating chamber in which the rotating electrical machine is accommodated, a cover member which is coupled to one end side of the accommodating member in an axial direction, faces the rotating electrical machine in the axial direction, and includes a supporting portion rotatably supporting the rotor, a power switching element electrically connected to a coil of the stator, and a smoothing capacitor electrically connected to the power switching element, wherein: the power switching element and the smoothing capacitor are fixed to the cover member, and are disposed between the cover member and the rotating electrical machine in the axial direction; and the smoothing capacitor overlaps the power switching element as seen in a radial direction.

Description

[Technical field]

[0001] The present disclosure relates to a vehicle drive system. [Background technology]

[0002] In a configuration including an accommodating member that forms an accommodating chamber in which a rotating electric machine is housed, and a cover member that covers an opening on one end side of the accommodating member in the axial direction, a structure is known in which a power switching element and a smoothing capacitor are arranged in the axial direction between the cover member and the rotating electric machine (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-138489 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the above-described conventional technology, the power switching element and the smoothing capacitor are arranged to overlap when viewed in the axial direction, so that the axial size of the vehicle drive device cannot be efficiently reduced.

[0005] Therefore, the present disclosure aims to efficiently reduce the axial size of a vehicle drive device in a configuration including a rotating electric machine housing member and a cover member, while arranging a power switching element and a smoothing capacitor in the axial direction between the cover member and the rotating electric machine. [Means for solving the problem]

[0006] According to one aspect of the present disclosure, a rotating electric machine having a rotor and a stator; an accommodation member that defines an accommodation chamber in which the rotating electric machine is accommodated; a cover member that is axially connected to one end side of the housing member, that faces the rotating electric machine in the axial direction, and that has a support portion that rotatably supports the rotor; a power switching element electrically connected to the coil of the stator; a smoothing capacitor electrically connected to the power switching element; the power switching element and the smoothing capacitor are fixed to the cover member and are disposed between the cover member and the rotating electric machine in the axial direction; A vehicle drive device is provided, wherein the smoothing capacitor overlaps with the power switching element when viewed in a radial direction. Effect of the Invention

[0007] According to the present disclosure, in a configuration including a housing member for a rotating electric machine and a cover member, it is possible to efficiently reduce the axial size of a vehicle drive device while arranging a power switching element and a smoothing capacitor in the axial direction between the cover member and the rotating electric machine. [Brief description of the drawings]

[0008] [Figure 1] 1 is a schematic diagram of an example of an electric circuit including a rotating electric machine according to a first embodiment. [Diagram 2] 1 is a skeleton diagram of a vehicle drive system including a rotating electric machine according to a first embodiment. [Figure 3A] 1 is a cross-sectional view that illustrates a schematic view of a main part of a vehicle drive device according to a first embodiment. [Figure 3B] FIG. 4 is another cross-sectional view showing the cooling water channel structure. [Figure 3C] 13 is a perspective view of the cover member as viewed from the X2 side. FIG. [Figure 3D] 13 is a schematic cross-sectional view illustrating a layer structure of a molded resin portion according to a modified example. FIG. [Figure 4] 3A and 3B are diagrams each showing an example of a coil side that forms a stator coil; [Diagram 5] FIG. [Figure 6]FIG. 3B is an enlarged view of part Q1 in FIG. 3A. [Figure 7] 1 is a perspective view of a motor drive device according to a first embodiment, as viewed from the X1 side. [Figure 8] 1 is a perspective view of a power module and a capacitor module arranged on a cover member according to a first embodiment, as viewed from the X2 side. FIG. [Figure 9] FIG. 2 is an explanatory diagram for explaining the configuration of the power module and the capacitor module according to the first embodiment as well as the ease of assembly. [Figure 10] FIG. 2 is an explanatory diagram of an electric circuit formed by the block assembly according to the first embodiment. [Figure 11] 4 is a schematic diagram showing an example of a method of electrical connection between the rotating electric machine and the block assembly according to the first embodiment. FIG. [Figure 12] 2 is a perspective view of a power bus bar in a wiring portion of the motor drive device according to the first embodiment, as viewed from the X1 side. FIG. [Figure 13] FIG. 2 is a plan view illustrating a control board according to the first embodiment. [Figure 13A] 13 is a cross-sectional view that shows a schematic view of a main part of a vehicle drive device according to a modified example. [Figure 14A] FIG. 2 is a schematic perspective view illustrating a rotating electric machine in which six block assemblies according to the first embodiment are arranged in the circumferential direction. [Figure 14B] FIG. 2 is a schematic perspective view illustrating a rotating electric machine in which only three block assemblies according to the first embodiment are arranged in the circumferential direction. [Figure 15] FIG. 11 is a schematic explanatory diagram of a wiring structure of a vehicle drive device according to a comparative example. [Figure 16] FIG. 2 is a schematic explanatory diagram of an example of a wiring structure that can be realized in the rotating electric machine according to the first embodiment. [Figure 17A] FIG. 4 is a schematic explanatory diagram of another example of a wiring structure that can be realized in the rotating electric machine according to the first embodiment. [Figure 17B] 4 is an equivalent electric circuit diagram for explaining another example of a wiring structure that can be realized in the rotating electric machine according to the first embodiment. FIG. [Figure 18] FIG. 2 is a schematic explanatory diagram of specifications that can be realized by the rotating electric machine according to the first embodiment. [Figure 19] FIG. 11 is a perspective view showing a vehicle drive device according to a second embodiment, as viewed from the X1 side. [Figure 20] FIG. 11 is a perspective view showing the vehicle drive device according to the second embodiment, viewed from the X2 side. [Figure 21] FIG. 11 is a perspective view showing a pipe member according to a second embodiment from the X1 side. [Figure 22] FIG. 11 is a perspective view showing a pipe member according to a second embodiment from the X2 side. [Figure 23] FIG. 11 is a cross-sectional view of a main part of a vehicle drive device according to a second embodiment. [Figure 24] FIG. 11 is a cross-sectional view of a main part of a vehicle drive device according to another embodiment. [Diagram 25] FIG. 11 is a cross-sectional view of a main portion of a vehicle drive device according to still another embodiment. [Figure 26] FIG. 11 is a cross-sectional view that shows a schematic view of a main part of a vehicle drive device according to a third embodiment. [Figure 27] FIG. 11 is a schematic cross-sectional view illustrating a sub-assembly state in which a motor drive device is mounted on a cover member according to a third embodiment. [Figure 28] FIG. 11 is an explanatory diagram showing a cooling water channel structure suitable for a cover member according to a third embodiment, and is a plan view viewed in the axial direction. [Figure 29] FIG. 11 is an explanatory diagram showing a motor drive device applied to a vehicle drive device of a third embodiment. [Diagram 30] 11 is an explanatory diagram showing the positional relationship between a cooling water channel structure and a motor drive device according to a third embodiment. FIG. [Diagram 31] FIG. 11 is a cross-sectional view showing a schematic layout of a main part of a motor drive device according to a first modified example. [Diagram 32] FIG. 11 is a cross-sectional view showing a schematic layout of a main part of a motor drive device according to a second modified example. [Diagram 33] FIG. 11 is a cross-sectional view showing a schematic layout of a main part of a motor drive device according to a third modified example. [Diagram 34] FIG. 1 is an explanatory diagram of layout-related terms. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Each embodiment will be described in detail below with reference to the accompanying drawings. Note that the dimensional ratios in the drawings are merely examples and are not intended to be limiting, and shapes and the like in the drawings may be partially exaggerated for the sake of explanation.

[0010] In the following, an overview will be given of the electrical system (control system) of the vehicle drive device 10 of this embodiment and the entire drive system including the vehicle drive device 10 of this embodiment, and then the vehicle drive device 10 of this embodiment will be described in detail.

[0011] [Vehicle drivetrain electrical system] Fig. 1 is a schematic diagram of an example of an electric circuit 200 including a rotating electric machine 1 of this embodiment. A control device 500 is also shown in Fig. 1. In Fig. 1, dotted arrows associated with the control device 500 indicate the exchange of information (signals and data).

[0012] The rotating electric machine 1 is driven through the control of the inverter INV by the control device 500. In the electric circuit 200 shown in FIG. 1, the rotating electric machine 1 is electrically connected to the power source Va through the inverter INV. The inverter INV includes, for example, power switching elements (e.g., MOSFET: Metal-Oxide-Semiconductor Field Effect Transistor, IGBT: Insulated Gate Bipolar Transistor, etc.) on the high potential side and low potential side of the power source Va for each phase, and the power switching element on the high potential side and the power switching element on the low potential side form upper and lower arms. The inverter INV may include a plurality of sets of upper and lower arms for each phase. Each power switching element may be PWM (Pulse Width Modulation) driven under the control of the control device 500 so as to generate a desired rotational torque. The power source Va is, for example, a battery with a relatively high rated voltage, and may be, for example, a lithium ion battery or a fuel cell.

[0013] In this embodiment, as in the electric circuit 200 shown in Fig. 1, a smoothing capacitor C is electrically connected in parallel to the inverter INV between the high potential side and the low potential side of the power supply Va. Note that a plurality of sets of smoothing capacitors C may be electrically connected in parallel between the high potential side and the low potential side of the power supply Va. Also, a DC / DC converter may be provided between the power supply Va and the inverter INV.

[0014] [Entire drive system] Fig. 2 is a skeleton diagram of a vehicle drive system 100 including a rotating electric machine 1. In Fig. 2, an X direction and an X1 side and an X2 side along the X direction are defined. The X direction is parallel to the direction of a first axis A1 (hereinafter also referred to as the "axial direction").

[0015] 2, the vehicle drive system 100 includes a rotating electric machine 1 that serves as a drive source for the wheels, and a drive transmission mechanism 7 provided in a power transmission path that connects the rotating electric 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, 62.

[0016] The input member 3 has an input shaft 31 and an input gear 32. The input shaft 31 is a rotating member that rotates around the first axis A1. The input gear 32 is a gear that transmits rotational torque (driving force) from the rotating electric machine 1 to the counter gear mechanism 4. The input gear 32 is connected to the input shaft 31 of the input member 3 so as to rotate integrally with the input shaft 31 of the input member 3.

[0017] The counter gear mechanism 4 is disposed in the power transmission path between the input member 3 and the differential gear mechanism 5. The counter gear mechanism 4 has a counter shaft 41, a first counter gear 42, and a second counter gear 43.

[0018] The counter shaft 41 is a rotating member that rotates around the second shaft A2. The second shaft A2 extends parallel to the first shaft A1. The first counter gear 42 is an input element of the counter gear mechanism 4. The first counter gear 42 meshes with the input gear 32 of the input member 3. The first counter gear 42 is connected to the counter shaft 41 so as to rotate integrally therewith.

[0019] The second counter gear 43 is an output element of the counter gear mechanism 4. In the present embodiment, for 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 with the counter shaft 41.

[0020] The differential gear mechanism 5 is disposed on a third axis A3 serving as the rotation axis thereof. 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 left and right output members 61, 62. The differential gear mechanism 5 includes a differential input gear 51 that meshes with a second counter gear 43 of the counter gear mechanism 4. The differential gear mechanism 5 also includes a differential case 52 that houses a pinion shaft, a pinion gear, left and right side gears, etc. The left and right side gears are connected to the left and right output members 61, 62 so as to rotate integrally therewith, respectively.

[0021] The left and right output members 61, 62 are drivingly connected to the left and right wheels W, respectively. The left and right output members 61, 62 transmit the driving force distributed by the differential gear mechanism 5 to the wheels W. Note that the left and right output members 61, 62 may be constituted by two or more members.

[0022] In this way, the rotating electric machine 1 drives the wheels W via the drive transmission mechanism 7. However, in other embodiments, the rotating electric machine 1 may be disposed in the wheels as a wheel-in motor. In this case, the vehicle drive system 100 may not include the drive transmission mechanism 7. Also, in other embodiments, a plurality of rotating electric machines 1 may be provided, sharing part or all of the drive transmission mechanism 7.

[0023] [Vehicle drive unit details] The vehicle drive device 10 includes the above-mentioned rotating electric machine 1, a case 2, and a motor drive device 8.

[0024] FIG. 3A is a cross-sectional view showing a schematic view of a main part of the vehicle drive device 10 of this embodiment. FIG. 3A is a cross-sectional view cut along a plane passing through the first axis A1, which is the rotation axis of the rotating electric machine 1, and shows a part of one axial end side (X1 side) of the rotating electric machine 1. In the following description, unless otherwise specified, the axial direction refers to the direction in which the first axis A1, which is the rotation axis of the rotating electric machine 1, extends, and the radial direction refers to the radial direction centered on the first axis A1. Therefore, the radial outer side refers to the side away from the first axis A1, and the radial inner side refers to the side toward the first axis A1. Also, the circumferential direction corresponds to the direction of rotation around the first axis A1. Also, in FIG. 3A, the X direction, and the X1 side and X2 side along the X direction are defined as in FIG. 2. In the following description, the terms X1 side and X2 side may be used to indicate a relative positional relationship. Fig. 3B is another cross-sectional view (cut along a line different from that of Fig. 3A) of the vehicle drive device 10, which shows a schematic cooling water channel structure. Fig. 3C is a perspective view of the cover member 252 seen from the X2 side. Fig. 3D is a schematic cross-sectional view for explaining the layer structure of the molded resin part 2523A according to a modified example. Fig. 4 is a diagram showing a schematic example of a coil side 121 forming the stator coil 322.

[0025] The vehicle drive device 10 is mounted on a vehicle as a part of the vehicle drive system 100, and generates a driving force for moving the vehicle forward or backward as described above. The vehicle may be in any form, and may be, for example, a four-wheeled automobile, a bus, a truck, a motorcycle, construction machinery, or the like. The vehicle drive device 10 may be mounted on the vehicle together with another drive source (for example, an internal combustion engine).

[0026] The rotating electric machine 1 has a rotor 310 and a stator 320. Fig. 3A shows a part of one axial end side (X1 side) of the rotating electric machine 1. The rotating electric machine 1 is an inner rotor type, and the stator 320 is provided so as to surround the radial outside of the rotor 310. In other words, the rotor 310 is disposed radially inside the stator 320.

[0027] The rotor 310 includes a rotor core 312 and a shaft portion 314 .

[0028] Rotor core 312 may be made of, for example, annular laminated steel plates of magnetic material. Permanent magnets 325 may be embedded inside rotor core 312. Alternatively, permanent magnets 325 may be attached to the outer circumferential surface of rotor core 312. The arrangement of permanent magnets 325 is arbitrary. Rotor core 312 is fixed to the outer circumferential surface of shaft portion 314 and rotates integrally with shaft portion 314.

[0029] The shaft portion 314 defines a first axis A1 which is a rotation axis of the rotating electric machine 1. The shaft portion 314 is rotatably supported by a cover member 252 (described later) of the case 2 via a bearing 240 on the X1 side of a portion to which the rotor core 312 is fixed. The shaft portion 314 is rotatably supported by the case 2 via a bearing corresponding to the bearing 240 on the other axial end side (X2 side) of the rotating electric machine 1. In this manner, the shaft portion 314 may be rotatably supported by the case 2 at both axial ends.

[0030] The shaft portion 314 is in the form of, for example, a hollow tube and has a hollow interior 314A. The hollow interior 314A may extend over the entire axial length of the shaft portion 314. The hollow interior 314A may function as an axial oil passage. In this case, the shaft portion 314 may be formed with an oil hole that discharges oil to the coil end portion 322A of the stator 320, etc.

[0031] The shaft portion 314 is provided with a detection target portion 3141 of the rotation angle sensor 900 that acquires rotation angle information of the rotor 310 on the X1 side of the portion to which the rotor core 312 is fixed. The rotation angle sensor 900 may be, for example, a rotary encoder using a sensor element such as a Hall element or a magnetoresistance element. In this embodiment, the detection target portion 3141 is provided adjacent to the bearing 240 from the X2 side in the axial direction. When the sensor element of the rotation angle sensor 900 is a Hall element, the detection target portion 3141 may be realized by a permanent magnet provided on the outer periphery of the shaft portion 314. In this case, the permanent magnet is arranged such that the magnetic pole of the outer periphery of the shaft portion 314 changes periodically along the circumferential direction, and a plurality of sensor elements of the rotation angle sensor 900 may be arranged at equal pitches around the first axis A1 in a manner that faces the detection target portion 3141 in the radial direction. It should be noted that the detected portion 3141 may be in the form of a ring attached to the shaft portion 314, or may be formed integrally with the shaft portion 314.

[0032] The stator 320 includes a stator core 321 and a stator coil 322 .

[0033] Stator core 321 may be made of, for example, laminated steel plates of a magnetic material having a circular ring shape. Teeth (not shown) are formed radially on the inner periphery of stator core 321 and protrude radially inward.

[0034] The stator coil 322 may be in the form of, for example, a conductor having a rectangular or circular cross section with an insulating coating. The stator coil 322 is wound around teeth (not shown) of the stator core 321. The stator coils 322 may be electrically connected in a Y-connection or a Δ-connection in parallel with one or more coils.

[0035] The stator coil 322 has a coil end portion 322A that is a portion that protrudes axially outward from the slot of the stator core 321. For example, the stator coil 322 may be realized by assembling a plurality of coil sides 121 as shown in FIG. 4 to the stator core 321. In the example shown in FIG. 4, the coil side 121 includes slot insertion portions 1211 and 1214 that are inserted into two slots, crossover portions 1215A and 1215B, and end portions 1210 and 1218. In this case, the crossover portions 1215A and 1215B and the end portions 1210 and 1218 form the coil end portion 322A. The stator coil 322 may be formed of a coil of another form, for example, a coil other than a cassette coil form. In the following description, unless otherwise specified, coil end portion 322A refers to a part of stator coil 322, which is a portion extending circumferentially on each of the axial sides of stator core 321, and which extends along one axial end side (X1 side), which is the lead side, of the portions extending circumferentially on each of the axial sides of stator core 321.

[0036] The case 2 may be made of aluminum, for example. The case 2 may be formed by casting or the like. The case 2 includes a motor case 250 and a cover member 252. The case 2 houses the rotating electric machine 1 and the motor drive device 8. In the case of the vehicle drive system 100 shown in FIG. 2, the case 2 may further house a drive transmission mechanism 7, as shown typically in FIG. 2.

[0037] The motor case 250 forms a motor housing chamber SP1 that houses the rotating electric machine 1. The motor housing chamber SP1 may be an oil-tight space that contains oil for cooling and / or lubricating the rotating electric machine 1 (and / or the drive transmission mechanism 7). The motor case 250 has a peripheral wall that surrounds the radial outside of the rotating electric machine 1. The motor case 250 may be realized by joining a plurality of members. The motor case 250 may be integrated with another case member that houses the drive transmission mechanism 7 at the other axial end side (X2 side).

[0038] The cover member 252 is coupled to one axial end side (X1 side) of the motor case 250. The cover member 252 is in the form of a cover that covers one axial end side (X1 side) of the motor accommodating chamber SP1. In this case, the cover member 252 may cover the opening of the one axial end side (X1 side) of the motor case 250 in such a manner that it completely or almost completely blocks the opening.

[0039] The cover member 252 forms an inverter accommodating chamber SP2 that accommodates the motor drive device 8. Note that a part of the inverter accommodating chamber SP2 may be formed by the motor case 250, and conversely, a part of the motor accommodating chamber SP1 may be formed by the cover member 252.

[0040] The cover member 252 supports the motor drive device 8. For example, the motor drive device 8 may be attached to the cover member 252 in the form of a module, which will be described later. This allows the cover member 252 and the motor case 250 to be joined after a part or the whole of the motor drive device 8 is assembled to the cover member 252, improving the ease of assembly of the motor drive device 8.

[0041] Bearing 240 that rotatably supports rotor 310 is provided on cover member 252. That is, cover member 252 has a bearing support portion 2524 that supports bearing 240. Note that bearing support portion 2524 refers to the entire axial range of cover member 252 where bearing 240 is provided.

[0042] 3A, bearing 240 is provided on the radially outer side of the end portion on the X1 side of shaft portion 314. Specifically, bearing 240 has a radially outer side of an outer race supported by cover member 252, and a radially inner side of an inner race supported by the outer peripheral surface of shaft portion 314. Note that in a modified example, bearing 240 may be configured conversely such that a radially inner side of an inner race is supported by cover member 252, and a radially outer side of the outer race is supported by the inner peripheral surface of shaft portion 314.

[0043] In this embodiment, as shown in FIG. 3A and FIG. 3C, the cover member 252 includes annular bottom portions 2521, 2521A centered on the first axis A1, and a peripheral wall portion 2522 protruding from the inner peripheral edge of the bottom portion 2521 toward the other axial end side (X2 side), and the bottom portion 2521 and the peripheral wall portion 2522 define an inverter accommodating chamber SP2. A cylindrical portion 25211 protruding toward the other axial end side (X2 side) is formed in the center portion (part centered on the first axis A1) of the other axial end side (X2 side) of the bottom portion 2521, and a bearing support portion 2524 is set in the cylindrical portion 25211. The cylindrical portion 25211 is formed concentrically with the first axis A1 as the center. A first cooling water passage 25281 and a second cooling water passage 25282, which will be described later, may be formed in the bottom portions 2521, 2521A, respectively.

[0044] The inverter accommodation chamber SP2 may be a space, but is preferably sealed with a resin containing a filler having a relatively high thermal conductivity. That is, the cover member 252 preferably has a thermally conductive molded resin part 2523. In this case, the molded resin part 2523 can have a function of sealing and supporting the motor drive device 8 described later, a function of protecting the motor drive device 8 against oil in the motor accommodation chamber SP1, and a function of transmitting heat from the motor drive device 8 to the cover member 252. Note that in FIG. 3A, elements (such as a block assembly 90 described later) sealed in the molded resin part 2523 are shown in a see-through manner. The formation range of the molded resin part 2523 is not limited to the range shown in FIG. 3A, etc., and may extend only from the bottom 2521 side to the X1 side, or may extend to the X2 side.

[0045] Also, like the molded resin part 2523A of the vehicle drive device 10A of the modified example shown in FIG. 3D, the molded resin part 2523A may have a layered structure made of a plurality of resin materials. Specifically, the molded resin part 2523A has a layered structure in the axial direction including a first resin layer 25231 and a second resin layer 25232. In this case, the first resin layer 25231 is preferably disposed on the side closer to the rotating electric machine 1 than the second resin layer 25232 in the axial direction (i.e., the X2 side), and has lower thermal conductivity than the second resin layer 25232. For example, the first resin layer 25231 may be formed of a resin material with relatively high thermal insulation (for example, a foamed resin material), and the second resin layer 25232 may be formed of a resin material with relatively high thermal conductivity (for example, a resin material containing a metal filler or the like). Such molded resin portion 2523A can efficiently transfer heat from motor drive device 8 to cover member 252 while suppressing heat reception from coil end portion 322A in motor drive device 8. In this case, cooling of coil end portion 322A may be achieved by a separate cooling system (for example, an oil passage and / or a cooling water passage in motor case 250).

[0046] The molded resin portion 2523 also has a function of fixing the motor drive device 8 including the capacitor module 82 (described later) and the like to the cover member 252. In this case, the molded resin portion 2523 may be formed so as to seal the entire capacitor module 82.

[0047] The cover member 252 is preferably formed of a material (e.g., aluminum) having a relatively high thermal conductivity, and has a cooling water passage 2528 therein. Water flows in the cooling water passage 2528 as cooling water. The water may be, for example, water containing LLC (Long Life Coolant). In this case, the cooling water flowing through the cooling water passage 2528 can be maintained at a relatively low temperature by dissipating heat in a radiator (not shown) mounted on the vehicle. When the cooling water flows through the cooling water passage 2528 of the cover member 252, the heat of the cover member 252 is taken by the cooling water, and the cover member 252 is cooled. This allows the cover member 252 to have a function of cooling the motor drive device 8 disposed adjacent thereto in the axial direction. That is, the heat from the motor drive device 8 is taken by the cooling water via the cover member 252, and the cooling of the motor drive device 8 is promoted. Such a cooling function can be further promoted by the above-mentioned molded resin part 2523. In a modified example, other refrigerant (for example, oil) may be used instead of the cooling water.

[0048] The cooling water passage 2528 may have any shape when viewed in the axial direction, for example, it may be annular, spiral, or extend circumferentially while meandering radially outward and inward. Fins or the like may be formed on the cooling water passage 2528. When the cover member 252 is manufactured using a core or the like, the degree of freedom of the shape of the cooling water passage 2528 can be increased.

[0049] Here, in this embodiment, as shown in FIG. 3B, the cooling water passage 2528 has a first cooling water passage 25281 and a second cooling water passage 25282. The first cooling water passage 25281 has an annular shape when viewed in the axial direction, and faces a power module 80 (described later) when viewed in the axial direction. This allows the power module 80 to be cooled over the entire circumference of the first cooling water passage 25281. The second cooling water passage 25282 has an annular shape when viewed in the axial direction, and faces a condenser module 82 (described later) when viewed in the axial direction. This allows the condenser module 82 to be cooled over the entire circumference of the second cooling water passage 25282. The first cooling water passage 25281 and the second cooling water passage 25282 communicate with each other through a radial connection flow passage 25283 (see FIG. 3A). The first cooling water passage 25281 is preferably disposed upstream of the second cooling water passage 25282 (closer to the discharge side of the water pump, not shown). That is, an inlet portion (an inlet portion formed in the cover member 252) (not shown) to the cooling water passage 2528 is preferably connected to the first cooling water passage 25281. With such a configuration, the submodule 800 (power semiconductor chips 801, 802) (described later) of the power module 80, which is more likely to become hot than the capacitor module 82, can be efficiently cooled by the cooling water (relatively fresh cooling water) in the first cooling water passage 25281 upstream of the second cooling water passage 25282.

[0050] Motor drive device 8 includes the above-mentioned inverter INV, smoothing capacitor C, control device 500, etc. Details of the elements of motor drive device 8 will be described later with reference to Figs.

[0051] 3A, motor driving device 8 is disposed between cover member 252 and rotating electric machine 1 in the axial direction. That is, motor driving device 8 is disposed in inverter accommodating chamber SP2.

[0052] In this manner, according to this embodiment, the motor driving device 8 is disposed between the cover member 252 and the rotating electric machine 1, so that the overall size of the vehicle driving device 10 can be reduced compared to when the motor driving device 8' is mounted outside the motor case 250' (see FIG. 5).

[0053] In particular, according to this embodiment, by providing the bearing support portion 2524 in the cover member 252 and arranging the motor drive device 8 between the cover member 252 and the rotating electric machine 1 in the axial direction, it is possible to reduce the axial size of the vehicle drive device 10. Specifically, when the motor drive device 8 is provided on the X1 side of the cover member 252 in the axial direction, a separate cover member for covering the X1 side of the motor drive device 8 is required, which is likely to lead to an increase in the axial size of the vehicle drive device 10. In this regard, according to this embodiment, the cover member 252 can function as a cover on the X1 side not only for the rotating electric machine 1 but also for the motor drive device 8, so it is possible to reduce the axial size of the vehicle drive device 10.

[0054] Furthermore, in this embodiment, the bearing support portion 2524 of the cover member 252 is disposed radially inward of the motor drive device 8 (such as the power module 80 and the capacitor module 82 described below) as viewed in the axial direction, and overlaps with the motor drive device 8 as viewed in the radial direction. This allows the motor drive device 8 to be disposed between the cover member 252 and the rotating electric machine 1 in the axial direction while reducing the axial dimension of the cover member 252 (the dimension from the bearing support portion 2524 to the X2 side). As a result, the axial size of the vehicle drive device 10 can be further effectively reduced.

[0055] Furthermore, according to this embodiment, a bracket having a bearing support portion corresponding to the bearing support portion 2524 is not provided between the motor drive device 8 and the rotating electric machine 1 in the axial direction. This reduces the number of parts and shortens the axial distance between the motor drive device 8 and the rotating electric machine 1 compared to a configuration in which such a bracket is provided, and as a result, the axial size of the vehicle drive device 10 can be reduced as described above. Furthermore, since there is no wall portion (bracket) that separates the motor drive device 8 and the rotating electric machine 1 in the axial direction, the wiring length between the motor drive device 8 and the rotating electric machine 1 can be shortened, and the wiring efficiency between the motor drive device 8 and the rotating electric machine 1 can be improved.

[0056] Furthermore, according to this embodiment, when the cooling water passage 2528 is formed in the cover member 252, the cover member 252 can be thermally connected (connected in a manner that allows thermal conduction) to the motor drive device 8. That is, the motor drive device 8 can be cooled by the cooling water in the cooling water passage 2528 via the cover member 252. Since the cooling water can be stably flowed through the cooling water passage 2528, the cooling of the motor drive device 8 can be stabilized. Furthermore, when the flow rate of the cooling water can be controlled, it is also possible to optimize the cooling according to the state of the motor drive device 8.

[0057] Furthermore, according to this embodiment, by shortening the axial distance between the motor drive device 8 and the rotating electric machine 1, it becomes possible to cool not only the motor drive device 8 but also a part of the rotating electric machine 1 by the cover member 252 (the cover member 252 having the cooling water passage 2528). For example, the above-mentioned molded resin part 2523 may be thermally connected to the stator coil 322 of the rotating electric machine 1. Specifically, by bringing the molded resin part 2523 into contact with or close to the coil end part 322A of the rotating electric machine 1, the coil end part 322A can be cooled by the cooling water in the cooling water passage 2528 via the molded resin part 2523 and the cover member 252.

[0058] Next, a specific example of the motor driving device 8 will be described with reference to FIGS.

[0059] FIG. 6 is an enlarged view of a portion Q1 in FIG. 3A. FIG. 7 is a perspective view of the motor drive device 8 as viewed from the X1 side. FIG. 8 is a perspective view of the power module 80 and the capacitor module 82 arranged on the cover member 252 as viewed from the X2 side. FIG. 9 is an explanatory view for explaining the configuration of the power module 80 and the capacitor module 82 as well as the ease of assembly. FIG. 10 is an explanatory view of an electric circuit formed by a block assembly 90. FIG. 11 is a schematic view showing an example of an electrical connection method between the rotating electric machine 1 and the block assembly 90. FIG. 12 is a perspective view of a power bus bar 886 of the wiring portion 88 of the motor drive device 8 as viewed from the X1 side. FIG. 13 is a plan view showing a schematic view of the control board 84.

[0060] The motor drive device 8 includes a power module 80, a capacitor module 82, a control board 84, and a wiring section 88. Note that in Fig. 7, the control board 84 and part of the wiring section 88 (such as lead wires 888 and relay bus bars 889) are omitted from illustration.

[0061] In this embodiment, the power modules 80 and the capacitor modules 82 are arranged in a plurality of pairs (12 pairs in the example shown in FIG. 7) along the circumferential direction as shown in FIG. 7. The number of pairs of the power modules 80 and the capacitor modules 82 is changed according to the specifications of the rotating electric machine 1. Basically, as the number of pairs of the power modules 80 and the capacitor modules 82 increases, the output of the rotating electric machine 1 increases. Therefore, when designing the rotating electric machine 1, multiple variations with different numbers of pairs of the power modules 80 and the capacitor modules 82 can be set.

[0062] The power modules 80 and the capacitor modules 82 are preferably arranged at equal pitches along the circumferential direction for each pair. For example, in the example shown in Fig. 7, the number of pairs of the power modules 80 and the capacitor modules 82 is 12, and the 12 pairs are arranged at 30 degree pitches. This makes it possible to uniformize the temperature distribution along the circumferential direction caused by the heat from the power modules 80 and the capacitor modules 82. However, in modified examples, a different pitch may be used.

[0063] The power module 80 and the capacitor module 82 are preferably in the form of an integrated assembly in each of the multiple sets. That is, the power module 80 and the capacitor module 82 in each set form an integrated block assembly 90. FIG. 9 shows a schematic diagram of a method for forming the block assembly 90 for one set. In this case, the power module 80 and the capacitor module 82 can be assembled to the cover member 252 in a sub-assembled state (see FIG. 8). This improves the ease of assembly. Specifically, the assembly method can include a step of assembling the motor drive device 8 to the cover member 252, and a step of assembling the cover member 252 to which the motor drive device 8 is assembled, to the motor case 250. The step of assembling the motor drive device 8 to the cover member 252 can be performed with good workability because the power module 80 and the capacitor module 82 can be assembled to the cover member 252 in a sub-assembled state. The step of assembling the motor drive device 8 to the cover member 252 may include a step of forming the molded resin portion 2523 described above. This allows the motor drive device 8 and the cover member 252 to be firmly joined together, and therefore the workability of the process of assembling the cover member 252 to which the motor drive device 8 is attached, into the motor case 250 is also improved.

[0064] In each of the block assemblies 90, the power modules 80 have the same configuration, and the capacitor modules 82 have the same configuration (electrical characteristics, shape, etc.). This allows replacement and maintenance of each block assembly 90, improving versatility. In this embodiment, in each of the block assemblies 90, the power module 80 includes a submodule 800 and a heat dissipation member 810. In this case, in each of the block assemblies 90, the submodules 800 have the same configuration (electrical characteristics, shape, etc.), and the heat dissipation members 810 have the same configuration (material, shape, etc.). This eliminates the need to consider which block assembly 90 is to be placed at which circumferential position when arranging a plurality of block assemblies 90 in the circumferential direction, improving assembly. The term "same electrical characteristics" means that there is no significant difference in the electrical characteristics, and is a concept that ignores slight differences due to individual differences. The electrical characteristic may be any characteristic, but for example, the electrical characteristic of the capacitor module 82 may be a rated capacitance, etc., and the electrical characteristic of the submodule 800 (power semiconductor chips 801, 802) may be a gate threshold voltage, etc. Similarly, having the same shape means that there is no significant difference in shape, and is a concept that ignores slight differences due to individual differences (for example, differences in dimensions within the allowable tolerances, etc.).

[0065] For example, among the 12 block assemblies 90, the four block assemblies 90 for the U phase may be arranged adjacent to each other in the circumferential direction as a single block, the four block assemblies 90 for the V phase may be arranged adjacent to each other in the circumferential direction as a single block, and the four block assemblies 90 for the W phase may be arranged adjacent to each other in the circumferential direction as a single block. In this case, it is possible to reduce the number of relay busbars 889 described later. Alternatively, the block assemblies 90 for the U phase, the block assemblies 90 for the V phase, and the block assemblies 90 for the W phase may be arranged periodically, one by one or two by two, along the circumferential direction.

[0066] Each of the submodules 800 forms an upper and lower arm associated with one phase of the inverter INV (see FIG. 1). This allows submodules to be formed for each upper and lower arm, improving wiring efficiency. Specifically, in four of the 12 power modules 80, each of the submodules 800 forms an upper and lower arm associated with the U phase, in the other four power modules 80, each of the submodules 800 forms an upper and lower arm associated with the V phase, and in the remaining four power modules 80, each of the submodules 800 forms an upper and lower arm associated with the W phase.

[0067] Moreover, in each block assembly 90, the submodule 800 has a pair of power semiconductor chips 801, 802. Specifically, the pair of power semiconductor chips 801, 802 is composed of a power semiconductor chip 801 forming an upper arm on the high potential side (see P in FIG. 10) and a power semiconductor chip 802 forming a lower arm on the low potential side (see N in FIG. 10). Each of the power semiconductor chips 801, 802 includes the above-mentioned power switching element.

[0068] 9, the power semiconductor chip 801 and the power semiconductor chip 802 are preferably integrated with a heat dissipation member 810. This allows the above-mentioned power module 80 to integrally include the heat dissipation member 810, and allows the heat of the pair of power semiconductor chips 801, 802 to be efficiently dissipated via the heat dissipation member 810. Furthermore, the ease of assembly can be improved compared to the case where the pair of power semiconductor chips 801, 802 and the heat dissipation member 810 are separately assembled to the cover member 252 or the capacitor module 82.

[0069] 9, the power semiconductor chip 801 and the power semiconductor chip 802 have bus bars 881, 882, 883, and 884 as parts of the wiring section 88. The bus bar 881 integrated with the power semiconductor chip 801 electrically connects the power semiconductor chip 801 to the capacitor module 82 (for example, the capacitor bus bar 821 in FIG. 9). The bus bar 883 integrated with the power semiconductor chip 801 protrudes toward the radially inner coupling surface 8104 of the heat dissipation member 810, and electrically connects the power semiconductor chip 801 to the stator coil 322 of the corresponding phase in the rotating electric machine 1 (for example, the end 1210 or 1218 in the coil side 121 shown in FIG. 4). Similarly, the bus bar 882 integrated with the power semiconductor chip 802 electrically connects the power semiconductor chip 802 to the capacitor module 82 (for example, the capacitor bus bar 822 in FIG. 9). In addition, the bus bar 884 integrated with the power semiconductor chip 802 protrudes toward the radially inner connecting surface 8104 of the heat dissipation member 810, and electrically connects the power semiconductor chip 802 to the stator coil 322 of the corresponding phase in the rotating electric machine 1 (the end 1210 or 1218 of the coil side 121 shown in Figure 4).

[0070] In this embodiment, the pair of power semiconductor chips 801, 802 are bonded to side surfaces 8101, 8102 in the circumferential direction of the heat dissipation member 810. At this time, the power semiconductor chip 801 is bonded to the side surface (surface) 8102 on one side in the circumferential direction of the heat dissipation member 810, and the power semiconductor chip 802 is bonded to the side surface (surface) 8101 on the other side in the circumferential direction of the heat dissipation member 810. Note that any bonding method may be used, and an adhesive material with relatively high thermal conductivity may be used. This allows the heat dissipation member 810 to efficiently receive heat from the pair of power semiconductor chips 801, 802 via the side surface in the circumferential direction. In addition, the pair of power semiconductor chips 801, 802 can be arranged by efficiently utilizing the space between the heat dissipation members 810 adjacent to each other in the circumferential direction. Moreover, by arranging the power semiconductor chips 801, 802 of the upper and lower arms on different side surfaces (circumferential side surfaces) 8101, 8102 of the heat dissipation member 810, the power semiconductor chips 801, 802 of the upper and lower arms can be efficiently electrically connected to each other on the radially inner side via the bus bars 883, 884 and the relay bus bar 889. Moreover, the power semiconductor chips 801, 802 of the upper and lower arms can be efficiently electrically connected to the capacitor module 82 (and power supply Va) on the radially outer side (the side of the radially outer coupling surface 8103 of the heat dissipation member 810).

[0071] The heat dissipation member 810 is made of a material (e.g., aluminum) having a relatively high thermal conductivity. In this embodiment, the heat dissipation member 810 is in the form of a solid block. This makes it possible to efficiently increase the heat capacity of the heat dissipation member 810.

[0072] The heat dissipation member 810 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 passage 2528).

[0073] In this embodiment, as described above, the pair of power semiconductor chips 801, 802 are joined to the circumferential side surface of the heat dissipation member 810, so that the axial surface (for example, the surface on the X1 side) is free. This allows the heat dissipation member 810 to be disposed in close proximity to or in contact with the cover member 252 (and the cooling water passage 2528 therewith) in the axial direction. In this case, the heat of the pair of power semiconductor chips 801, 802 can be efficiently transferred to the cover member 252 (and the cooling water in the cooling water passage 2528 therewith) via the heat dissipation member 810. The surface on the other axial side (X2 side) of the heat dissipation member 810 may be used for cooling elements on the control board 84, etc.

[0074] 6, in this embodiment, the heat dissipation member 810 abuts against the cover member 252 in the axial direction. This allows the heat of the heat dissipation member 810 to be efficiently transferred to the cover member 252 (and thus the cooling water in the cooling water passage 2528). Furthermore, the heat dissipation member 810 overlaps the cooling water passage 2528 when viewed in the axial direction. This allows the heat of the heat dissipation member 810 to be even more efficiently transferred to the cover member 252 (and thus the cooling water in the cooling water passage 2528).

[0075] As shown in FIG. 7, the heat dissipation member 810 is preferably configured such that the circumferential width becomes smaller toward the radially inner side as viewed in the axial direction. That is, the heat dissipation member 810 is preferably configured such that the distance L1 between the circumferential side surfaces to which the pair of power semiconductor chips 801, 802 are joined is smaller on the side closer to the first axis A1 in the radial direction than on the side farther from the first axis A1. This makes it possible to relatively easily establish the layout of the heat dissipation member 810 even when the number of pairs of power modules 80 and capacitor modules 82 (i.e., the number of block assemblies 90) is relatively large while arranging the heat dissipation member 810 radially inner than the capacitor module 82. Also, even when the pair of power semiconductor chips 801, 802 are arranged on the circumferential side surfaces, it is possible to easily secure the arrangement space (arrangement space of the heat dissipation member 810) on the radially inner side. However, in another embodiment, the distance L1 may be constant (see FIG. 11).

[0076] Capacitor module 82 is in the form of a module that forms a smoothing capacitor C (see FIG. 1). Capacitor module 82 may be in the form in which capacitor elements that form smoothing capacitor C and capacitor bus bars 821, 822 (see FIG. 9) of wiring section 88 are sealed with resin. Each end of capacitor bus bars 821, 822 exposed from the sealing resin section forms a high-potential side terminal of the capacitor element and a low-potential side terminal of the capacitor element, respectively. Capacitor bus bars 821, 822 are connected to submodule 800 and are also connected to power supply bus bar 886 (see FIGS. 3A, 6, and 12).

[0077] In each of the block assemblies 90, the capacitor module 82 forms a smoothing capacitor C that is electrically connected in parallel between the high potential side and the low potential side of the corresponding set of sub-modules 800, as shown in FIG.

[0078] In this embodiment, the capacitor module 82 is disposed radially outward of the power module 80. This allows the capacitor module 82 to be disposed over a wider circumferential range than when it is disposed radially inward of the power module 80, making it easier to increase the size of the capacitor module 82. For example, even when the number of sets of power modules 80 and capacitor modules 82 is relatively large, a relatively large capacitor module 82 can be realized. As a result, it becomes easier to accommodate increased output from the rotating electric machine 1.

[0079] 6, in this embodiment, the axial extension range of the capacitor module 82 overlaps with the axial extension range of the power module 80. In particular, in this embodiment, the sub-module 800 of the power module 80 overlaps with the capacitor module 82 when viewed in the radial direction. This makes it possible to arrange the capacitor module 82 and the sub-module 800 between the cover member 252 and the rotating electric machine 1 in the axial direction while minimizing the axial size of the vehicle drive device 10.

[0080] Capacitor module 82 is disposed so as to be equidistant from each of power semiconductor chips 801, 802. In this case, capacitor bus bar 821 (see FIG. 9) connected to each of power semiconductor chips 801, 802 can be shared.

[0081] The capacitor module 82 is thermally connected to the cover member 252. For example, the capacitor module 82 may be thermally connected to the cover member 252 via a heat dissipation member 810. The capacitor module 82 can be thermally connected to the heat dissipation member 810 by being radially opposed to a radially outer coupling surface 8103 of the heat dissipation member 810 (the coupling surface 8103 coupling two side surfaces 8101, 8102 to which the pair of power semiconductor chips 801, 802 are fixed) (see FIG. 9 ). In this case, the heat dissipation member 810 may have a radially outer protrusion (not shown) that is close to the capacitor module 82.

[0082] Alternatively, the capacitor module 82 may be thermally connected directly to the cover member 252 without the heat dissipation member 810 or in addition to the thermal connection via the heat dissipation member 810. Specifically, the capacitor module 82 extends to a side farther from the rotating electric machine 1 than the submodule 800 in the axial direction (i.e., the X1 side) and is close to or in contact with the cover member 252 in the axial direction. In this embodiment, the capacitor module 82 is in axial contact with the cover member 252 as in the case of the heat dissipation member 810, as shown in FIG. 6. In this case, the heat of the capacitor module 82 can be efficiently transferred to the cover member 252 (and the cooling water in the cooling water passage 2528). The capacitor module 82 may also be in radial contact with the peripheral wall portion 2522 of the cover member 252.

[0083] Alternatively, the capacitor module 82 may be thermally connected to the cover member 252 via the molded resin portion 2523 instead of or in addition to these thermal connection methods.

[0084] In this way, by thermally connecting the capacitor module 82 to the cover member 252, the heat of the capacitor module 82 can be efficiently transferred to the cover member 252 (and the cooling water in the cooling water passage 2528), thereby efficiently cooling the capacitor module 82.

[0085] In particular, in this embodiment, the axial extension ranges of the capacitor module 82, the heat dissipation member 810, and the submodule 800 (power semiconductor chips 801, 802) overlap with each other, thereby minimizing the axial mounting space of the motor drive device 8 while improving the heat transfer performance to the cover member 252 via the heat dissipation member 810.

[0086] Moreover, the X2 side end of the capacitor module 82 preferably extends further toward the X2 side than the coil end portion 322A. That is, the capacitor module 82 overlaps the coil end portion 322A when viewed in the radial direction. This makes it possible to minimize the axial gap between the capacitor module 82 and the rotating electric machine 1. As a result, it is possible to reduce the axial size of the vehicle drive device 10 while ensuring the necessary axial size of the capacitor module 82.

[0087] Moreover, the capacitor module 82 is preferably disposed radially outward of the coil end portion 322A as viewed in the axial direction. This makes it possible to realize a layout in which the capacitor module 82 overlaps the coil end portion 322A as viewed in the radial direction. In this case, the capacitor module 82 may be disposed so as to overlap the back yoke portion of the stator core 321 as viewed in the axial direction. In this case, since the capacitor module 82 can be disposed relatively radially inward, it is possible to reduce the possibility or the amount of increase in the radial size of the motor case 250 due to the capacitor module 82 being disposed radially outward of the power module 80.

[0088] The control board 84 forms a part or the whole of the control device 500 (see FIG. 1). The control board 84 may be formed, for example, by a multilayer printed circuit board. The control board 84 is arranged such that the normal direction to the board surface is along the axial direction. This allows the control board 84 to be arranged by utilizing a small gap in the axial direction. For example, in this embodiment, the control board 84 may be arranged between the rotating electric machine 1 and the power module 80 in the axial direction as shown in FIG. 6. More specifically, the control board 84 may be arranged between the coil end portion 322A of the rotating electric machine 1 and the power module 80 in the axial direction. This allows for an efficient arrangement by utilizing a space that is likely to become a dead space. In addition, the control board 84 can extend radially outward to a radial position overlapping the coil end portion 322A when viewed in the axial direction, so that the area of ​​the control board 84 (circuit portion formation range) can be maximized.

[0089] The control board 84 preferably overlaps with the capacitor module 82 as viewed in the radial direction. In the example shown in Fig. 6, the end of the capacitor module 82 on the X2 side extends further toward the X2 side than the coil end portion 322A, and overlaps with the submodule 800 as viewed in the radial direction. In this layout, in order for the control board 84 to overlap with the capacitor module 82 as viewed in the radial direction, it is sufficient that the control board 84 is disposed between the coil end portion 322A of the rotating electric machine 1 and the power module 80 (or the submodule 800 of the power module 80) in the axial direction.

[0090] The control board 84 is preferably in the form of an annular ring having a central hole 84a through which the shaft portion 314 (see also FIG. 3A) of the rotor 310 passes. In this case, the control board 84 can be disposed in the vicinity of any of the multiple power modules 80 arranged along the circumferential direction. This facilitates electrical connection (not shown) between the power semiconductor chips 801, 802 (e.g., gate terminals of power switching elements) forming the submodule 800 of the power module 80 and a drive circuit 846 (see FIG. 13) of the control board 84.

[0091] As shown in FIG. 13, the control board 84 has an annular low-voltage area 841 around the central hole 84a and an annular high-voltage area 842 radially outward from the low-voltage area 841. The high-voltage area 842 and the low-voltage area 841 are electrically insulated via an annular insulating area 843. This allows low-voltage circuits and high-voltage circuits to coexist in each of the two annular areas (the low-voltage area 841 and the high-voltage area 842) in the control board 84. In the high-voltage area 842 in the control board 84, circuit sections and elements that handle high voltage related to the power supply Va are arranged. For example, the high-voltage area 842 may be provided with a drive circuit 846 for driving the power semiconductor chips 801 and 802 as a high-voltage electronic component. In addition, the low-voltage area 841 may be provided with a microcomputer (abbreviation of microcomputer) 502 and a power supply circuit 503 that realize the control device 500 as a low-voltage electronic component. Incidentally, electronic components for an electric oil pump that circulates oil inside the motor housing chamber SP1 may be mounted on the control board 84.

[0092] In this embodiment, the control board 84 has a through hole 845 through which a lead wire 888 (an element of the wiring portion 88) electrically connecting the stator coil 322 and the power semiconductor chips 801 and 802 passes in the low voltage region 841 (see FIG. 6). This allows the lead wire 888 to be established with a relatively short wiring length while ensuring the necessary size of the control board 84. For example, in the case of the coil side 121 shown in FIG. 4, the lead wire 888 may be realized by the end portions 1210 and 1218. In the example shown in FIG. 6, the lead wire 888 is bent radially inward from the coil end portion 322A and drawn radially inward, and is bent in the axial direction on the X1 side of the rotor core 312 and extends in the axial direction. The lead wire 888 penetrates the control board 84 in the axial direction in a section extending in the axial direction. In the example shown in FIG. 13, the control board 84 has three through holes 845 corresponding to the three-phase stator coil 322. 11, the end of the lead wire 888 on the X1 side may be joined to a relay bus bar 889. In this case, the bus bars 883, 884 from the power module 80 described above are joined to the relay bus bar 889. A relay bus bar 889 may be provided for each phase, or two or more lead wires 888 for each phase may be joined to a common relay bus bar 889.

[0093] In this embodiment, the control board 84 is provided with a current sensor 902 around the through hole 845 by utilizing a configuration in which the lead wire 888 passes through the through hole 845. In this case, the current sensor 902 can easily detect the current passing through the lead wire 888. The current sensor 902 may be, for example, a Hall sensor. The current sensor 902 is electrically connected to the microcomputer 502 (see FIG. 13) associated with the control device 500 via wiring in the control board 84 (not shown). This allows the wiring between the current sensor 902 and the control device 500 to be easily realized by the wiring in the control board 84, and also allows the length of the wiring between the current sensor 902 and the control device 500 to be shortened.

[0094] In this embodiment, the control board 84 is provided with a rotation angle sensor 900. The rotation angle sensor 900 faces the detection target 3141 (the detection target 3141 provided on the shaft portion 314 described above, see FIG. 6) in the radial direction. Specifically, the rotation angle sensor 900 is provided at a position around the central hole 84a (i.e., the opening edge portion). The rotation angle sensor 900 may be formed integrally with the control board 84 and function as a magnetic pole position sensor. This allows wiring between the rotation angle sensor 900 and the control device 500 to be easily achieved by wiring within the control board 84, and also allows the length of wiring between the rotation angle sensor 900 and the control device 500 to be shortened.

[0095] The wiring section 88 includes the capacitor bus bars 821 and 822 described above, the bus bars 881, 882, 883 and 884 described above, a power supply bus bar 886, the lead wire 888 described above, and the relay bus bar 889 described above.

[0096] The power bus bar 886 has an annular shape as shown in Fig. 12, and extends around the first axis A1 as shown in Fig. 6 (and Fig. 3A). In this embodiment, the power bus bar 886 extends in the circumferential direction between the cover member 252 and the submodule 800 in the axial direction, adjacent to the submodule 800 from the X1 side. In this case, the power bus bar 886 is disposed radially inward of the capacitor module 82 as viewed in the axial direction, and overlaps with the capacitor module 82 as viewed in the radial direction. This makes it possible to efficiently reduce the wiring length between the power bus bar 886 and each block assembly 90.

[0097] The power supply busbar 886 includes a high potential side power supply busbar 8861 electrically connected to the high potential side of the power supply Va (see FIG. 1), and a low potential side power supply busbar 8862 electrically connected to the low potential side of the power supply Va (see FIG. 1). The high potential side power supply busbar 8861 and the low potential side power supply busbar 8862 may be disposed offset from each other in the radial direction and / or axial direction as shown in FIG. 7. The high potential side power supply busbar 8861 may be joined to the X1 side end of the capacitor busbar 821, and the low potential side power supply busbar 8862 may be joined to the X1 side end of the capacitor busbar 822.

[0098] The power supply bus bar 886 is preferably disposed closer to the cover member 252 than the submodule 800 (power semiconductor chips 801, 802). For example, as shown in Fig. 3A, the power supply bus bar 886 may be disposed between the capacitor bus bar 822 and the heat dissipation member 810 in the radial direction, and on the X1 side of the submodule 800. In this case, the power supply bus bar 886 can be disposed efficiently by utilizing a space that could become a dead space, while the heat from the power supply bus bar 886 can be efficiently transferred to the cover member 252 (i.e., the power supply bus bar 886 can be efficiently cooled).

[0099] In addition, in a vehicle drive device 10B of a modified example shown in FIG. 13A, the power supply bus bar 886B is provided in an annular groove 2529 formed in the cover member 252. The annular groove 2529 has an annular shape around the first axis A1 when viewed in the axial direction, and is recessed toward the X1 side. The power supply bus bar 886B may extend between the first cooling water passage 25281B and the second cooling water passage 25282B in the radial direction when viewed in the axial direction. In this case, the power supply bus bar 886B can be efficiently arranged by utilizing the space between the first cooling water passage 25281B and the second cooling water passage 25282B of the cooling water passage 2528B in the radial direction, and the power supply bus bar 886B can be efficiently cooled by the first cooling water passage 25281B and the second cooling water passage 25282B.

[0100] Next, some of the effects of this embodiment will be described with reference to FIGS. 14A to 18.

[0101] Fig. 14A is a schematic perspective view illustrating a rotating electric machine 1A in which only six block assemblies 90 are arranged along the circumferential direction, and Fig. 14B is a schematic perspective view illustrating a rotating electric machine 1B in which only three block assemblies 90 are arranged along the circumferential direction. Note that Figs. 14A and 14B are diagrams for explaining the arrangement of the block assemblies 90, and therefore some elements may be illustrated in a simplified manner or omitted.

[0102] As described above, in this embodiment, each block assembly 90 has the same configuration and can be mounted in any number, making it possible to realize rotating electric machines 1 with a variety of specifications. For example, by arranging six block assemblies 90 as shown in Fig. 14A or three block assemblies 90 as shown in Fig. 14B, it is possible to easily configure rotating electric machines 1A and 1B with different outputs relative to the rotating electric machine 1. This makes it possible to efficiently increase the variety of rotating electric machines while sharing parts.

[0103] Figure 15 is a schematic explanatory diagram of the wiring structure of a vehicle drive device 10' according to a comparative example, Figure 16 is a schematic explanatory diagram of an example of a wiring structure that can be realized by the rotating electric machine 1 according to this embodiment, Figures 17A and 17B are schematic explanatory diagrams of another example of a wiring structure that can be realized by the rotating electric machine 1 according to this embodiment, and Figure 18 is a schematic explanatory diagram of specifications that can be realized by the rotating electric machine 1 according to this embodiment.

[0104] The vehicle drive device 10' according to the comparative example is configured such that the power module PM' including the above-mentioned inverter INV, smoothing capacitor C, control device 500, etc. (not shown) is disposed outside the motor case 250'. In this case, as shown in FIG. 15, a wiring structure is adopted in which lead wires (power lines) from the rotating electric machine M' are drawn to the power module PM' through a partition wall of the motor case 250'. In such a wiring structure, the wiring length of the lead wires from the rotating electric machine M' tends to be long, and the degree of freedom of the wiring path is also not high.

[0105] In contrast, in this embodiment, as described above, the motor drive device 8 is adjacent to the rotating electric machine 1 in the axial direction without a partition (see FIG. 3A), so that the block assemblies 90 of each phase (in FIG. 16, they are written as "U", "V", and "W" to indicate the difference between the phases) can be arranged in the immediate vicinity of the stator coil 322, as shown in FIG. 16 (see FIG. 3A). This makes it possible to minimize the wiring length of the lead wire 888. In addition, since the wiring length is short, the electrical characteristics are good, the necessary reliability can be easily ensured, and the wiring can be easily arranged, thereby increasing the degree of freedom in the layout of the peripheral members. In this way, according to this embodiment, an efficient wiring structure can be realized.

[0106] In this embodiment, since a variety of numbers of block assemblies 90 can be arranged for each phase relay busbar 889 (FIG. 11), the number of block assemblies 90 that can be arranged in one rotating electric machine 1 can be increased in freedom as described above without complicating the wiring structure.

[0107] In addition, in this embodiment, as shown in Figs. 17A and 17B, even if the stator coils 322 are connected in parallel for each phase, an efficient wiring structure can be realized. That is, as in the example shown in Fig. 16, the block assemblies 90 for each phase can be disposed in the immediate vicinity of the coil end portions 322A of the stator coils 322, as shown in Figs. 17A and 17B. When the stator coils 322 are connected in parallel for each phase, the current required to generate the same output and passed through the stator coils 322 can be reduced compared to when the stator coils 322 are connected in series (see Fig. 16). For example, when three stator coils are connected in parallel as shown in Figs. 17A and 17B, the same output as when a current of 300 A is passed in the case of series connection (see Fig. 16) can be realized by passing a current of 100 A. By increasing the number of parallel connections in this way, it is possible to miniaturize the power semiconductor chips 801 and 802 included in the submodule 800 and increase the yield of semiconductor wafers. In this way, by distributing the inverter modules using the block assembly 90 and parallelizing (distributing) the connections of the stator coils 322 to the inverter INV, it is possible to reduce not only the size but also the cost and increase the variety of winding configurations. For example, in order to increase the variety of winding configurations, a winding configuration other than three phases, such as a nine-phase winding configuration, can be used as shown in FIG.

[0108] In addition, in this embodiment, since there is a high degree of freedom in the number of block assemblies 90 that can be arranged in one rotating electric machine 1, for example, in the case of the connection mode of the stator coil 322 shown in Figures 17A and 17B, three block assemblies 90 can be arranged for each phase. In this case, it is also possible to independently energize the stator coils 322-1 to 322-3 that are connected in parallel, and it is also possible to enhance redundancy such as a fail-safe function.

[0109] Next, a vehicle drive device 10C according to another embodiment (hereinafter, for the sake of distinction, referred to as "embodiment 2") different from the vehicle drive device 10 according to the embodiment described above (hereinafter, for the sake of distinction, referred to as "embodiment 1") will be described with reference to Figures 19 to 25. In the following, components that may be similar to those in embodiment 1 described above may be given the same reference numerals and descriptions thereof may be omitted.

[0110] FIG. 19 is a perspective view showing vehicle driving device 10C of this embodiment from the X1 side, FIG. 20 is a perspective view showing vehicle driving device 10C from the X2 side, FIG. 21 is a perspective view showing tube member 70 from the X1 side, and FIG. 22 is a perspective view showing tube member 70 from the X2 side. FIG. 23 is a cross-sectional view of a main part of vehicle driving device 10C of this embodiment, and is a cross-sectional view corresponding to FIG. 6. FIG. 24 is a cross-sectional view of a main part of vehicle driving device 8C' according to another embodiment. FIG. 25 is a cross-sectional view of a main part of vehicle driving device 8C" according to yet another embodiment.

[0111] A vehicle drive device 10C of the present embodiment differs from the vehicle drive device 10 according to the above-described first embodiment in that the motor drive device 8 is replaced with a motor drive device 8C. The motor drive device 8C of the present embodiment differs from the motor drive device 8 according to the above-described first embodiment in that the power module 80 is replaced with a power module 80C and a pipe member 70 is provided. The power module 80C differs from the power module 80 according to the above-described first embodiment in that the heat dissipation member 810 is replaced with a heat dissipation member 810C.

[0112] The heat dissipation member 810C has a different shape from the heat dissipation member 810 according to the first embodiment described above, but has the same basic function. Specifically, the heat dissipation member 810 according to the first embodiment described above is in the form of a solid block (metal block), whereas the heat dissipation member 810C according to this embodiment is in the form of a hollow, through which the tube member 70 passes. The heat dissipation member 810C has a heat-conductive molded resin part 811C (see FIG. 20) in the hollow. The material of the molded resin part 811C may be the same as that of the molded resin part 2523 described above. The molded resin part 811C may be formed in the same process as the molded resin part 2523. Note that the molded resin part 811C is not shown in FIG. 19, and a portion of the tube member 70 sealed by the molded resin part 811C (an insertion part 73 described later) is shown in a see-through manner in FIG. 20.

[0113] The pipe member 70 is disposed between the cover member 252 and the rotating electric machine 1 in the axial direction. The pipe member 70 communicates with the cooling water passage 2528 of the cover member 252. Therefore, the cooling water flowing in the cooling water passage 2528 flows in the flow path of the pipe member 70. Since the pipe member 70 passes through the hollow interior of the heat dissipation member 810C, the cooling water passing through the pipe member 70 can efficiently receive heat from the heat dissipation member 810C. That is, the heat dissipation member 810C can efficiently release heat through the cooling water passing through the pipe member 70. As a result, the capacitor module 82 and the submodule 800 (power semiconductor chips 801, 802) can be efficiently cooled through the heat dissipation member 810C. Note that, in another embodiment, the pipe member 70 may be communicated with the same cooling water supply source without passing through the cooling water passage 2528.

[0114] In this embodiment, the pipe member 70 preferably communicates with the first cooling water passage 25281 of the cooling water passage 2528 of the cover member 252. In this case, the submodule 800 (power semiconductor chips 801, 802), which is more likely to become hot than the capacitor module 82, can be efficiently cooled by the cooling water in the first cooling water passage 25281 upstream of the second cooling water passage 25282.

[0115] 21 and 22, in this embodiment, the pipe member 70 extends along the circumferential direction as a whole, and has an inlet portion 71 and an outlet portion 72 adjacent to each other in the circumferential direction at a predetermined circumferential position. The inlet portion 71 and the outlet portion 72 communicate with the cooling water passage 2528 of the cover member 252. Note that the pipe member 70 may be attached to the cover member 252 in a manner that the inlet portion 71 and the outlet portion 72 protrude into the cooling water passage 2528.

[0116] In this embodiment, the pipe member 70 is continuous from the inlet portion 71 to the outlet portion 72, and includes an insertion portion 73 and a transition portion 74. Each insertion portion 73 extends in the axial direction in a U-shape, and is inserted into the hollow interior of the heat dissipation member 810C (see the dotted line in FIG. 23). The transition portion 74 extends in the circumferential direction, and connects between adjacent insertion portions 73 in the circumferential direction. Such a pipe member 70 is relatively easy to manufacture, and is realized as a one-piece piece, which provides good assembly properties.

[0117] In a modified example, the transition portion 74 may be omitted, and each of the insertion portions 73 may communicate with the cooling water passage 2528 in a manner that each of the insertion portions 73 has an inlet portion 71 and an outlet portion 72 .

[0118] In this embodiment, the pipe member 70 forms the cooling water passage in the heat dissipation member 810C, but this is not limited thereto. For example, in a motor drive device 8C' shown in a schematic cross-sectional view in FIG. 24, the power module 80 according to the above-mentioned embodiment 1 is replaced with a power module 80C', and the power module 80C' has a cooling water passage 815 formed in the heat dissipation member 810C'. The heat dissipation member 810C' may be formed of two pieces, and the portion other than the cooling water passage 815 may be solid. The cooling water passage 815 communicates with the cooling water passage 2528 of the cover member 252, as shown in FIG. 24. With such a motor drive device 8C', the same effect as that of the above-mentioned embodiment 2 can be obtained with a reduced number of parts by not using the pipe member 70.

[0119] As another modification, as shown in the schematic cross-sectional view of FIG. 25, a heat dissipation member 89 may be provided between the block assembly 90 and the rotating electric machine 1 in the axial direction. In this case, the heat dissipation member 89 has heat dissipation properties and is made of, for example, aluminum. The heat dissipation member 89 is in the form of an annular ring having a central hole 89a through which the shaft portion 314 of the rotor 310 passes, and may be fixed to the shaft portion 314 by, for example, press-fitting. With this configuration, the heat dissipation member 89 can protect the control board 84 against heat from the rotating electric machine 1. Furthermore, the heat dissipation member 89 can protect the control board 84 by shielding electromagnetic waves, thereby improving the reliability of the control realized via the control board 84.

[0120] Next, a vehicle drive device 10D according to yet another embodiment (hereinafter, referred to as "embodiment 3" for distinction) will be described with reference to Fig. 26 to Fig. 30. In the following, components that may be similar to those in embodiment 1 described above (including components that differ only in arrangement or size) may be given the same reference numerals and descriptions thereof may be omitted. Also, in Fig. 26 etc., some of the components shown in Fig. 3A etc., but that may be included in the vehicle drive device 10D of this embodiment (e.g., the rotation angle sensor 900) may be omitted from illustration.

[0121] FIG. 26 is a cross-sectional view that illustrates a schematic view of a main part of a vehicle drive device 10D according to the third embodiment.

[0122] The vehicle drive device 10D according to the third embodiment is mainly different from the vehicle drive device 10 according to the first embodiment described above in that the capacitor module 82 is disposed on the X1 side of the control board 84D. In this case, in the first embodiment described above, the capacitor module 82 overlaps with the control board 84D and the coil end portion 322A when viewed in the radial direction, whereas in this embodiment, the capacitor module 82 does not overlap with the control board 84D and the coil end portion 322A when viewed in the radial direction.

[0123] According to this configuration, the control board 84D can be increased in diameter (or disposed radially outward). Specifically, as shown in FIG. 26, the control board 84D can extend radially outward to a position where it overlaps the capacitor module 82 as viewed in the axial direction or a position where it exceeds the capacitor module 82 radially outward. In this way, according to this embodiment, the degree of freedom in the arrangement and size of the control board 84D can be increased. However, in a modified example, the end of the capacitor module 82 on the X2 side may be disposed so as to overlap the coil end portion 322A as viewed in the radial direction, similar to the above-mentioned embodiment 1. In this case, instead of increasing the diameter of the control board 84D, the axial size of the capacitor module 82 can be increased (capacity can be increased).

[0124] In the third embodiment, the capacitor module 82 is disposed radially outward from the coil end portion 322A in a manner that does not overlap with the coil end portion 322A as seen in the axial direction, as in the first embodiment described above. However, in a modified example, the capacitor module 82 may be disposed radially inward in a manner that overlaps with the coil end portion 322A as seen in the axial direction. In this case, it is possible to reduce the radial size of the cover member 252D.

[0125] Moreover, the vehicle drive device 10D according to the third embodiment differs from the vehicle drive device 10 according to the above-described first embodiment in that the cover member 252 is replaced with a cover member 252D.

[0126] Here, in this embodiment, as described above, due to the capacitor module 82 being disposed on the X1 side of the control board 84D, the end of the X1 side of the capacitor module 82 extends further to the X1 side than the power module 80. That is, the capacitor module 82 extends further to the X1 side than the heat dissipation member 89 of the power module 80. For this reason, the cover member 252D has a step 2526D on the X2 side surface in accordance with the step on the X1 side of the power module 80 and the capacitor module 82. That is, the surface on the X2 side of the cover member 252D has a radially outer surface portion (a surface portion facing the capacitor module 82 in the axial direction) offset toward the X1 side from a radially inner surface portion (a surface portion facing the power module 80 in the axial direction). As a result, the cover member 252D can be brought into close proximity to or in contact with both the power module 80 and the capacitor module 82 in the axial direction, and therefore can effectively maintain thermal connection to both the power module 80 and the capacitor module 82.

[0127] In this embodiment as well, a cooling water passage 2528D having the same function as the cooling water passage 2528 according to the above-described embodiment 1 is formed in the cover member 252D. Like the cooling water passage 2528 according to the above-described embodiment 1, the cooling water passage 2528D has a first cooling water passage 25281D and a second cooling water passage 25282D.

[0128] In this embodiment, unlike the positional relationship between the cooling water passage 2528 and the condenser module 82 according to the first embodiment described above, the condenser module 82 overlaps with the first cooling water passage 25281D when viewed in the radial direction as shown in Fig. 26. That is, due to the step 2526D of the cover member 252D described above, the condenser module 82 faces the first cooling water passage 25281D in the radial direction. This makes it possible to slightly improve the cooling performance of the condenser module 82 by the first cooling water passage 25281D.

[0129] 26, in this embodiment, a power supply bus bar 886D is disposed between the first cooling water passage 25281D and the capacitor module 82 in the radial direction. That is, the power supply bus bar 886D is disposed near the step 2526D of the cover member 252D. This allows the power supply bus bar 886D to be efficiently disposed by utilizing the space between the first cooling water passage 25281D and the second cooling water passage 25282D in the radial direction, and allows the power supply bus bar 886D to be efficiently cooled by the first cooling water passage 25281D and the second cooling water passage 25282D.

[0130] FIG. 27 is a schematic cross-sectional view illustrating a sub-assembly state in which the motor drive device 8 is attached to the cover member 252 according to the present embodiment.

[0131] The cover member 252D has a bearing support portion 2524D similar to the bearing support portion 2524 according to the first embodiment described above. The bearing support portion 2524D is set in the cylindrical portion 25211D. In this embodiment, the cylindrical portion 25211D protrudes toward the X2 side in the X direction in a manner extending to a position overlapping the control board 84D when viewed in the radial direction or to a position exceeding the control board 84D in the X2 direction. In this case, as shown in FIG. 27, the power module 80, the capacitor module 82, and the control board 84D located radially outside the cylindrical portion 25211D can be completely sealed by the molded resin portion 2523D. That is, the motor drive device 8D and the control board 84D can be covered by the molded resin portion 2523D that does not have a step on the X2 side. This makes it easy to integrate the motor drive device 8 and the control board 84D with the cover member 252D by the molded resin portion 2523D. The molded resin portion 2523D may have a layered structure as described above with reference to FIG. 3D.

[0132] Fig. 28 is an explanatory diagram showing a cooling water channel structure suitable for the cover member 252D according to this embodiment, and is a plan view seen in the axial direction. In Fig. 28, the cooling water channel structure formed by the cover member 252D is shown in a see-through manner.

[0133] In this embodiment, similarly to the cooling water passage 2528 according to the first embodiment described above, the first cooling water passage 25281D has an annular shape when viewed in the axial direction and faces the power module 80 when viewed in the axial direction. The second cooling water passage 25282D has an annular shape when viewed in the axial direction and faces the capacitor module 82 when viewed in the axial direction. The first cooling water passage 25281D and the second cooling water passage 25282D communicate with each other through a radial connection flow passage 25283D. The first cooling water passage 25281D is preferably disposed upstream of the second cooling water passage 25282D (closer to the discharge side of the water pump not shown). That is, the cooling water passage 2528D further has an inlet water passage portion (inlet water passage portion formed in the cover member 252) 25288D to the first cooling water passage 25281D, and the inlet water passage portion 25288D is radially connected to the first cooling water passage 25281D as shown in Fig. 28. With this configuration, the submodule 800 (power semiconductor chips 801, 802, see Fig. 29) of the power module 80, which is more likely to become hot than the capacitor module 82, can be efficiently cooled by the cooling water in the first cooling water passage 25281D upstream of the second cooling water passage 25282D.

[0134] In this embodiment, since the first cooling water passage 25281D and the second cooling water passage 25282D are offset in the axial direction as described above, it is relatively easy to form the inlet water passage portion 25288D in the first cooling water passage 25281D located radially inward of the second cooling water passage 25282D. That is, the inlet water passage portion 25288D can extend radially outward in a manner straddling the second cooling water passage 25282D in the radial direction as shown in Fig. 28. Note that an end of the inlet water passage portion 25288D may be connected to a supply pipe of the cooling water passage (not shown).

[0135] 28, the cooling water passage 2528D further has an outlet water passage portion 25289D (outlet water passage portion formed in the cover member 252) from the second cooling water passage 25282D, and the outlet water passage portion 25289D from the second cooling water passage 25282D is disposed side by side with the inlet water passage portion 25288D to the first cooling water passage 25281D. This allows the attachment of the cooling water supply system and discharge system to the cover member 252D to be concentrated in one place, thereby improving the workability of such attachment.

[0136] 29 is an explanatory diagram showing motor drive device 8D applied to vehicle drive device 10D of this embodiment, and is a plan view of motor drive device 8D viewed in the axial direction from the X2 side. Note that motor drive device 8D described below is applicable to the above-mentioned embodiment 1 in a manner to be substituted for motor drive device 8 of vehicle drive device 10 according to the above-mentioned embodiment 1.

[0137] The motor drive device 8D according to this embodiment differs from the motor drive device 8 according to the first embodiment in the circumferential arrangement of the plurality of block assemblies 90. Specifically, this embodiment may be the same as the motor drive device 8 according to the above-mentioned embodiment in that a plurality of block assemblies 90 are provided for each phase of the rotating electric machine 1, and that a plurality of block assemblies 90 related to the same phase are arranged adjacent to each other along the circumferential direction of the rotating electric machine. On the other hand, the motor drive device 8D according to this embodiment differs from the motor drive device 8 according to the above-mentioned embodiment in that the circumferential distance between the block assemblies 90 related to different phases that are adjacent to each other in the circumferential direction is greater than the circumferential distance between the block assemblies 90 related to the same phase that are adjacent to each other in the circumferential direction. That is, in the motor drive device 8 according to the above-mentioned embodiment, the plurality of block assemblies 90 are arranged at equal intervals along the circumferential direction regardless of the difference between the phases, whereas in the motor drive device 8D according to this embodiment, the circumferential distance between the block assemblies 90 related to different phases that are adjacent to each other in the circumferential direction is greater than the circumferential distance between the block assemblies 90 related to the same phase that are adjacent to each other in the circumferential direction. This makes it possible to ensure an appropriate insulation distance between different phases adjacent to each other in the circumferential direction.

[0138] For example, in the example shown in Fig. 29, four block assemblies 90 for U-phase (in Fig. 29, labeled "90(U)" for distinction) among the 12 block assemblies 90 are arranged adjacent to each other in the circumferential direction as a single block, four block assemblies 90 for V-phase (in Fig. 29, labeled "90(V)" for distinction) are arranged adjacent to each other in the circumferential direction as a single block, and four block assemblies 90 for W-phase (in Fig. 29, labeled "90(W)" for distinction) are arranged adjacent to each other in the circumferential direction as a single block. In this case, for example, the four block assemblies 90(U) for U-phase are arranged at a distance d1 apart in the circumferential direction, whereas one block assembly 90(U) at the circumferential end for U-phase and one block assembly 90(V) at the circumferential end for V-phase are arranged at a distance d2 that is significantly larger than the distance d1. The same applies to the relationship between one block assembly 90(U) at the circumferential end for the U phase and one block assembly 90(W) at the circumferential end for the W phase, and also to the relationship between one block assembly 90(V) at the circumferential end for the V phase and one block assembly 90(W) at the circumferential end for the W phase.

[0139] In this embodiment, the relay busbar 889D is arranged by utilizing the space (the space between the block assemblies 90) that is separated by such a relatively large distance d2. The relay busbar 889D has the same function as the above-mentioned relay busbar 889, and is a busbar for electrically connecting the rotating electric machine 1 and the power module 80 (the midpoint of the upper and lower arms) for each phase.

[0140] In the example shown in Fig. 29, a relay busbar 889D for a U-phase (denoted as "889D(U)" in Fig. 29 for distinction) extends in the radial direction by utilizing the circumferential space (space of distance d2) between one block assembly 90(U) at the circumferential end for the U-phase and one block assembly 90(V) at the circumferential end for the V-phase. Similarly, a relay busbar 889D for a V-phase (denoted as "889D(V)" in Fig. 29 for distinction) extends in the radial direction by utilizing the circumferential space (space of distance d2) between one block assembly 90(V) at the circumferential end for the V-phase and one block assembly 90(W) at the circumferential end for the W-phase. Similarly, the W-phase relay busbar 889D (in FIG. 29, for the sake of distinction, it is written as "889D(W)") extends radially by utilizing the circumferential space (space of distance d2) between one block assembly 90(W) at the circumferential end for the W-phase and one block assembly 90(W) at the circumferential end for the W-phase.

[0141] More specifically, the relay busbar 889D(U) for the U phase includes an arc-shaped portion 8891D extending in the circumferential direction, a radial portion 8892D extending in the radial direction, and a connection end portion 8893D on the radial inner side of the four block assemblies 90(U) for the U phase. The radial portion 8892D continues from one end of the arc-shaped portion 8891D, passes through a space of a distance d2, and extends radially outward to the radial position of the capacitor module 82 of the four block assemblies 90(U) for the U phase. The connection end portion 8893D continues from a radially outer end portion of the radial portion 8892D, and extends in the axial direction on the radial outer side of the control board 84D. Moreover, when the connection end portion 8893D extends to the X2 side beyond the control board 84D as shown in FIG. 26, it is bent radially inward and joined to the coil end portion 322A. Note that a part of the connection end portion 8893D (a part of the side connected to the coil end portion 322A) may be realized by another conductor drawn out from the rotating electric machine 1 side.

[0142] According to this configuration, unlike the lead wire 888 (see FIG. 3A) used in the above-described first embodiment, it is not necessary to route the wire through the through hole 845 of the control board 84, and therefore it is possible to eliminate the need for the through hole 845. As a result, it is possible to reduce the possibility that the element mounting area on the control board 84 will be reduced due to the wiring section 88D of the motor drive device 8D.

[0143] In this manner, according to the present embodiment, a circumferential space can be formed between the block assemblies 90 of different phases that are adjacent in the circumferential direction. As a result, the relay busbars 889D can be efficiently arranged by utilizing the space while an appropriate insulation distance is ensured between the different phases that are adjacent in the circumferential direction.

[0144] Fig. 30 is an explanatory diagram showing the positional relationship between the cooling water passage structure of this embodiment and motor drive device 8D, and is a plan view of motor drive device 8D viewed in the axial direction from the X1 side. In Fig. 30, the cooling water passage structure of this embodiment described above with reference to Fig. 28 is shown by dotted lines superimposed on motor drive device 8D shown in Fig. 29.

[0145] In this embodiment, as shown in Fig. 30, an inlet water channel portion 25288D extending in the radial direction is formed between block assemblies 90 relating to different phases adjacent in the circumferential direction when viewed in the axial direction. Note that in the example shown in Fig. 30, the inlet water channel portion 25288D extends in the radial direction by utilizing the circumferential space (space of distance d2) between one block assembly 90(U) at the circumferential end for the U phase and one block assembly 90(W) at the circumferential end for the W phase.

[0146] In the present embodiment, as described above, the capacitor module 82 overlaps with the first cooling water passage 25281D when viewed in the radial direction. Therefore, if the inlet water passage portion 25288D is extended in the radial direction at the axial position of the first cooling water passage 25281D, there is a risk of interference with the capacitor module 82. However, in the present embodiment, the circumferential space (space of distance d2) between one block assembly 90(U) at the circumferential end for the U phase and one block assembly 90(W) at the circumferential end for the W phase is utilized, so that the inlet water passage portion 25288D can be formed in the shortest path without interference with the capacitor module 82.

[0147] Next, modified examples of the layout of motor drive device 8 will be described with reference to Fig. 31 to Fig. 33. In the following, components that may be similar to those in the above-described first embodiment will be given the same reference symbols and descriptions thereof will be omitted in some cases.

[0148] Fig. 31 is a cross-sectional view showing a schematic layout of a main part of motor drive device 8E according to a first modified example. Fig. 31 (as well as Figs. 32 and 33 described later) shows only a portion of a vehicle drive device including motor drive device 8E on one side of first axis A1 and on the X-direction X1 side.

[0149] The motor drive device 8E according to the first modification is different from the motor drive device 8 according to the first embodiment in that the control board 84 is realized by two control boards 84E-1 and 84E-2. In this case, the control boards 84E-1 and 84E-2 are preferably disposed radially inward of the coil end portion 322A when viewed in the axial direction. In this case, for example, by bringing a heat dissipation member 810 (see FIG. 9) of the power module 80 and the coil end portion 322A close to each other in the axial direction, it is also possible to cool the coil end portion 322A via the heat dissipation member 810.

[0150] FIG. 32 is a cross-sectional view that shows a schematic layout of a main part of a motor drive device 8F according to a second modified example.

[0151] The motor drive device 8F according to the second modification is different from the motor drive device 8 according to the first embodiment in that the capacitor module 82 overlaps the coil end portion 322A when viewed in the axial direction. In this case, the capacitor module 82 does not overlap the coil end portion 322A when viewed in the radial direction, and extends to the X1 side beyond the coil end portion 322A. In this case, it is possible to make the radial size of the capacitor module 82 relatively large, or to reduce the radial size of the cover member 252 by shifting the arrangement of the capacitor module 82 radially inward. Note that, like the first modification, the second modification is different from the motor drive device 8 according to the first embodiment in that the control board 84 is realized by two control boards 84F-1 and 84-2F. However, the control boards 84F-1 and 84-2F may be integrated into one board.

[0152] FIG. 33 is a cross-sectional view that shows a schematic layout of a main part of a motor drive device 8G according to a third modified example.

[0153] The motor drive device 8G according to the third modification is different from the motor drive device 8 according to the first embodiment in the radial relationship between the power module 80 and the capacitor module 82. Specifically, in the third modification, the power module 80 is disposed radially outward of the capacitor module 82 when viewed in the axial direction. In this case, the power module 80 may overlap the coil end portion 322A when viewed in the axial direction. That is, the power module 80 may extend to the X1 side of the coil end portion 322A. The power module 80 overlaps the capacitor module 82 when viewed in the radial direction. Therefore, in the case of this modification, the effects of the first embodiment described above (for example, the axial size of the vehicle drive device 10 can be reduced, etc.) can be similarly achieved. In FIG. 33, the control board 84G is disposed radially outward of the power module 80, but other arrangements may be realized.

[0154] According to the third modified example, it is possible to easily increase the size (particularly the size in the circumferential direction) of the heat dissipation member 810 of the power module 80, compared to a layout in which the power module 80 is disposed radially inside the capacitor module 82. This makes it possible to efficiently improve the heat dissipation performance of the power module 80 via the heat dissipation member 810.

[0155] In the third modified example, the capacitor module 82 may be radially opposed to the heat dissipation member 810 of the power module 80 from the radially inner side. That is, the capacitor module 82 can be thermally connected to the heat dissipation member 810 by radially opposed to a radially inner coupling surface 8104 of the heat dissipation member 810 (the coupling surface 8104 coupling two side surfaces to which the pair of power semiconductor chips 801, 802 are fixed). At this time, the capacitor module 82 may abut against the radially inner surface of the heat dissipation member 810. With this configuration as well, the capacitor module 82 can be efficiently cooled via the heat dissipation member 810.

[0156] 31 to 33, the bearing support portion 2524 is disposed radially inside the power module 80 as viewed in the axial direction, and overlaps with the capacitor module 82 as viewed in the radial direction. Therefore, it is possible to achieve the same effect as in the first embodiment (for example, reducing the axial size of the vehicle drive device).

[0157] Finally, the definition of terms will be supplementarily explained with reference to Fig. 34. In this specification, as shown in Fig. 34, the concept of element C being disposed on the Z1 side in the Z direction relative to element B when viewed in the Y direction includes a relationship in which at least a part of element C is located on the Z1 side of a line tangent to element B on the Z1 side among lines parallel to the Y direction, as shown by the positional relationship indicated by the arrow 2900. In this case, the Y direction and the Z direction are orthogonal to each other, and the positional relationship of each element is the relationship when viewed in a direction perpendicular to the YZ plane.

[0158] Furthermore, the concept of element D being disposed between elements B and C in the Y direction includes a relationship in which at least a part of the extension range in the Y direction (coordinate range in the Y direction) of element D is between the extension range in the Y direction of element B and the extension range in the Y direction of element C, as in the positional relationship indicated by arrow 2900. In other words, the concept includes a relationship in which at least one straight line parallel to the Z direction that passes through element D can pass between elements B and C in the Y direction (without passing through either element B or element C).

[0159] Moreover, when viewed in the Y direction, the concept of element E overlapping element F includes a relationship in which at least one of the straight lines parallel to the Y direction passing through element E passes through element F, as in the positional relationship indicated by arrow 2902. Note that the straight line passing through an element here is a concept that excludes a straight line tangent to the element.

[0160] Although each embodiment has been described above in detail, it is not limited to the specific embodiment, and various modifications and changes are possible within the scope of the claims. It is also possible to combine all or a plurality of the components of the above-mentioned embodiments. Furthermore, among the effects of each embodiment, the effects related to the dependent claims are additional effects that are distinguished from the generic concept (independent claim).

[0161] For example, in the above-described embodiment 1 (similar to embodiment 2, etc.), the cover member 252 includes the cooling water passage 2528 as a cooler, but is not limited to this. For example, the cover member 252 may include air-cooling fins as another cooler instead of or in addition to the cooling water passage 2528.

[0162] In the third embodiment, the capacitor module 82 is disposed radially outward of the coil end portion 322A, but this is not limited thereto. That is, the capacitor module 82 may overlap the coil end portion 322A when viewed in the axial direction. In this case, the radial size of the cover member 252D can be reduced. [Explanation of symbols]

[0163] 10, 10C... vehicle drive device, 1, 1A, 1B... rotating electric machine, 310... rotor, 320... stator, 322... stator coil (coil of stator), 322A... coil end portion, 250... motor case (housing member), 252... cover member, 2524... bearing support portion (support portion), 2528, 2528B, 2528D... cooling water passage (cooler), 25281, 25281B, 25281D... first cooling water passage, 25282, 25282B, 25282D... second cooling water passage, 802... power semiconductor chip (power switching element), C... smoothing capacitor

Claims

1. a rotating electric machine having a rotor and a stator; an accommodation member that defines an accommodation chamber in which the rotating electric machine is accommodated; a cover member that is axially connected to one end side of the housing member, that faces the rotating electric machine in the axial direction, and that has a support portion that rotatably supports the rotor; a power switching element electrically connected to the coil of the stator; a smoothing capacitor electrically connected to the power switching element; a control board that is disposed between the power switching element and the rotating electric machine in the axial direction and controls the power switching element, the power switching element and the smoothing capacitor are fixed to the cover member and are disposed between the cover member and the rotating electric machine in the axial direction; the smoothing capacitor overlaps with the power switching element when viewed in a radial direction, the control board overlaps with the power switching element and the smoothing capacitor when viewed in the axial direction, and faces the rotating electric machine in the axial direction without a metal plate forming the housing member therebetween; the smoothing capacitor overlaps with the control board when viewed in a radial direction, the control board is in the form of an annular ring having a central hole through which the shaft portion of the rotor passes, has through holes through which wiring passes that electrically connects the coil of the stator and the power switching elements, and has a first annular region around the central hole and a second annular region radially outward of the first region and electrically insulated from the first region, A current sensor is provided on the control board around the through hole, The first region is provided with the through hole and a current sensor, or a rotation angle sensor that acquires information on a rotation angle of the rotor, A drive circuit that drives the power switching element is provided in the second area.

2. The vehicle drive device according to claim 1 , wherein the smoothing capacitor overlaps with a coil end portion of the stator when viewed in a radial direction.

3. The cover member has a first cooling water passage formed therein through which cooling water flows, the power switching element is thermally connected to the cover member while facing the first cooling water passage in the axial direction, 3 . The vehicle drive device according to claim 1 , wherein the smoothing capacitor is disposed radially outward of the first cooling water passage when viewed in the axial direction and overlaps with the first cooling water passage when viewed in the radial direction. 4 .

4. The vehicle drive device according to claim 1 , wherein the smoothing capacitor is disposed radially outward of a coil end portion of the stator as viewed in the axial direction.

5. a plurality of the power switching elements are arranged side by side in a circumferential direction around the rotation axis of the rotor, The vehicle drive device according to claim 1 , wherein a plurality of the smoothing capacitors are arranged side by side in a circumferential direction around the rotation axis of the rotor.

6. a power supply bus bar for electrically connecting the power switching element and the smoothing capacitor to a DC power supply, The vehicle drive device according to claim 5 , wherein the power supply bus bar is disposed radially between the power switching element and the smoothing capacitor as viewed in the axial direction.

7. the power switching element is fixed to the cover member via a heat dissipation member, The vehicle drive device according to claim 6 , wherein the power supply bus bar is disposed between the smoothing capacitor and the heat dissipation member in a radial direction.

Images