Rotating electrical machine unit

Abstract

A rotary electric machine unit according to the present disclosure comprises a rotary electric machine, an electric power conversion device, and a first cooling part that cools the electric power conversion device and has formed therein a first cooling flow path through which refrigerant flows. The electric power conversion device has a plurality of power modules and a capacitor unit. The first cooling flow path has: an inlet flow path; a first flow path that branches from the inlet flow path and, as seen from an axial direction, is formed at a position overlapping a first group of power modules among the plurality of power modules; a second flow path that branches from the inlet flow path and, as seen from the axial direction, is formed at a position overlapping a second group of power modules among the plurality of power modules, the second group being different from the first group; and an outlet flow path. The capacitor unit is disposed so as to surround the first cooling part from the radially outer side.

Description

Technical Field

[0001] The present disclosure relates to a rotating electrical machine unit. This application claims priority based on Japanese Patent Application No. 2022-090052 filed in Japan on June 2, 2022, and incorporates its content herein by reference.

Background Art

[0002] Conventionally, a rotating electrical machine unit in which a rotating electrical machine and a power conversion device are integrated is known. In Patent Document 1, a cooler for cooling the power conversion device is provided in the rotating electrical machine unit. A cooling flow path through which a refrigerant flows is formed in the cooler.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In Patent Document 1, a plurality of power modules are arranged along the flow of the refrigerant flowing through the cooling flow path. In the structure of Patent Document 1, since the temperature of the refrigerant on the downstream side of the cooling flow path is higher than the temperature of the refrigerant on the upstream side of the cooling flow path, there is a possibility that the power module arranged on the downstream side of the cooling flow path cannot be sufficiently cooled. That is, since a deviation in the temperature of the refrigerant occurs between the upstream side and the downstream side of the cooling flow path, it is difficult to cool a plurality of power modules uniformly.

[0005] The present disclosure has been made in view of the above circumstances, and an object thereof is to provide a rotating electrical machine unit capable of uniformly cooling a plurality of power modules and improving cooling performance.

Means for Solving the Problems

[0006] The rotating electrical machine unit according to the present disclosure includes a rotating electrical machine having a stator, a rotor that rotates around an axis with respect to the stator, and a plurality of coils wound around the stator, a power conversion device disposed side by side with the rotating electrical machine in an axial direction along the axis of the rotor, and a first cooling unit in which a first cooling flow path through which a refrigerant flows is formed to cool the power conversion device. The power conversion device includes a plurality of power modules electrically connected to the plurality of coils respectively, and a capacitor unit electrically connected to the plurality of power modules. The first cooling flow path includes an inlet flow path through which the refrigerant is supplied, a first flow path that branches from the inlet flow path and is formed at a position overlapping a first group of the plurality of power modules when viewed in the axial direction, a second flow path that branches from the inlet flow path and is formed at a position overlapping a second group of the plurality of power modules different from the first group when viewed in the axial direction, and an outlet flow path through which the refrigerant from the first flow path and the second flow path merges and is discharged from the first cooling unit. The capacitor unit is disposed so as to surround the first cooling unit from the outside in the radial direction.

Advantages of the Invention

[0007] According to the present disclosure, it is possible to provide a rotating electrical machine unit capable of uniformly cooling a plurality of power modules and improving cooling performance.

Brief Description of the Drawings

[0008]

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Mode for Carrying Out the Invention

[0009] Embodiment 1. Hereinafter, the rotating electrical machine unit 1 according to Embodiment 1 will be described with reference to the drawings. FIG. 1 is a circuit diagram of the rotating electrical machine unit 1. FIG. 2 is a perspective view of the rotating electrical machine unit 1. As shown in FIGS. 2 and 19, the rotating electrical machine unit 1 includes a rotating electrical machine 2, a power conversion device 3, and a cooler 4 (first cooling unit). The rotating electrical machine 2, the power conversion device 3, and the cooler 4 are integrated. Thereby, the size reduction of the rotating electrical machine unit 1 can be achieved. In this specification, the direction along the axis O (see FIG. 9) of the rotor 22 of the rotating electrical machine 2 is referred to as the "axial direction". Also, when viewed from the axial direction, the direction intersecting the axis O of the rotor 22 is referred to as the "radial direction", and the direction of orbiting around the axis O of the rotor 22 is referred to as the "circumferential direction".

[0010] First, referring to FIG. 1, the circuit configuration (electrical configuration) of the rotating electrical machine unit 1 will be described. In this embodiment, a rotating electrical machine unit of a six-phase drive system will be described as an example. The rotating electrical machine unit 1 is mounted on a vehicle, for example.

[0011] The rotating electrical machine 2 includes six coils 25U1, 25V1, 25W1, 25U2, 25V2, and 25W2 corresponding to each of the six phases (U1 phase, V1 phase, W1 phase, U2 phase, V2 phase, and W2 phase). In this specification, the coils 25U1, 25V1, 25W1, 25U2, 25V2, and 25W2 are also simply referred to as coils 25.

[0012] The power conversion device 3 includes a capacitor unit 34 and six power modules 35U1, 35V1, 35W1, 35U2, 35V2, and 35W2 corresponding to each of the six phases (U1 phase, V1 phase, W1 phase, U2 phase, V2 phase, and W2 phase). In this specification, the power modules 35U1, 35V1, 35W1, 35U2, 35V2, and 35W2 are also simply referred to as the power module 35.

[0013] DC power is input to the power conversion device 3 from a DC power source E such as a battery. The power conversion device 3 converts the DC power output from the DC power source E into AC power and supplies it to the rotating electrical machine 2.

[0014] The capacitor unit 34 is a smoothing capacitor that stabilizes the voltage so that it does not fluctuate significantly in response to power fluctuations on the DC power source E side or power fluctuations on the power module 35 side. The capacitor unit 34 has a plurality (two in this embodiment) of capacitor modules 51. Each capacitor module 51 is connected between the positive power supply terminal and the negative power supply terminal of the DC power source E. Each capacitor module 51 has a plurality of capacitor elements 52 connected in parallel. The capacitor module 51 may have only one capacitor element 52.

[0015] Each power module 35 is connected between the positive power supply terminal and the negative power supply terminal of the DC power source E. Each power module 35 includes an upper arm side switching element SW1 and diode D1, and a lower arm side switching element SW2 and diode D2. The switching elements SW1 and SW2 are, for example, IGBTs (Insulated Gate Bipolar Transistors) or SiC (Silicon Carbide). The switching elements SW1 and SW2 are connected in series. The connection point between the switching element SW1 and the switching element SW2 is electrically connected to the coil 25 of the corresponding phase. The diode D1 is connected in parallel to the switching element SW1 in the reverse direction. The diode D2 is connected in parallel to the switching element SW2 in the reverse direction.

[0016] Next, the structure of the rotating electrical machine unit 1 will be described.

[0017] <Rotating electrical machine> First, the rotating electrical machine 2 will be described with reference to FIGS. 9, 18, etc. FIG. 18 is a perspective view of the rotating electrical machine 2.

[0018] As shown in FIG. 9, the rotating electrical machine 2 includes a stator 21, a rotor 22, a shaft 23, a housing 24, a plurality of coils 25 (in this embodiment, six coils 25U1, 25V1, 25W1, 25U2, 25V2, 25W2), first and second bearings 26a, 26b, and a resolver 27.

[0019] The stator 21 is annular. The stator 21 is provided so as to surround the outer periphery of the rotor 22. The stator 21 is fixed to the housing 24.

[0020] The rotor 22 is provided inside the stator 21. The rotor 22 is rotatable about the axis O with respect to the stator 21.

[0021] A shaft 23 is disposed at the center of the rotor 22. One axial side (lower side) of the shaft 23 is an output side that transmits the rotation of the rotor 22 to a vehicle or the like.

[0022] The housing 24 houses the stator 21, the rotor 22, and the shaft 23. The housing 24 includes a lid portion 61, an inner cylinder portion 62, an outer cylinder portion 63, and a bottom portion 64.

[0023] The lid portion 61 is a circular plate-like member. The lid portion 61 is fixed to the upper end of the inner cylinder portion 62. The lid portion 61 covers the stator 21 and the rotor 22 from above. As shown in FIG. 18, a coil through-hole 61a through which the coil terminal 25a of the coil 25 is inserted is formed in the lid portion 61. The six coil through-holes 61a are arranged at equal intervals (60° intervals) in the circumferential direction. A joint accommodation hole 61b for accommodating a relay joint 47 described later is formed in the lid portion 61.

[0024] The inner cylinder part 62 is cylindrical. The inner cylinder part 62 covers the stator 21 from the radially outer side. The stator 21 is fixed to the inner cylinder part 62, for example, by shrink fitting or press fitting. The outer cylinder part 63 is cylindrical. The outer cylinder part 63 covers the inner cylinder part 62 from the radially outer side. The outer cylinder part 63 is fixed to the inner cylinder part 62, for example, by shrink fitting or press fitting. The inner cylinder part 62 and the outer cylinder part 63 constitute a second cooling part 65 for cooling the rotating electrical machine 2. Details of the second cooling part 65 will be described later.

[0025] The bottom part 64 is a circular plate-like member. The bottom part 64 is fixed to the lower end of the outer cylinder part 63. The bottom part 64 covers the stator 21 and the rotor 22 from below. An attachment part 64a for attaching the rotating electrical machine unit 1 to the vehicle is provided on the bottom part 64.

[0026] The coil 25 is wound around the stator 21. The coil 25 is, for example, distributed wound around the stator 21. As the coil 25, for example, a rectangular wire having a rectangular cross section with a side length of 0.5 to 6.0 mm is used. The coil terminals 25a of the coils 25 of each phase are electrically connected to the corresponding phase power module 35. As shown in FIG. 18, the six coil terminals 25a are arranged at equal intervals (60° intervals) in the circumferential direction. After the coil terminals 25a are inserted through the coil through holes 61a, they are bent radially outward, and then bent again and extend axially.

[0027] The resolver 27 detects the rotation angle of the shaft 23. As shown in FIG. 18, the resolver 27 includes a resolver stator 27a, a resolver rotor 27b, and a resolver harness 27c (signal line). The resolver stator 27a is fixed to the lid part 61. The resolver rotor 27b is attached to the upper end part (the non-output side end part) of the shaft 23.

[0028] The detection result of the resolver 27 is output to the control board 36 of the power conversion device 3, which will be described later, via the resolver harness 27c. The resolver harness 27c is drawn out from the resolver stator 27a, extends toward the control board 36, and is connected to the control board 36. The resolver harness 27c extends while avoiding the portion where the power module 35 is disposed. Thereby, it is possible to prevent noise caused by the power module 35 from being transmitted to the resolver harness 27c, and the detection accuracy of the rotation angle of the shaft 23 can be improved.

[0029] A first bearing 26a is provided at the upper end portion (the non-output side end portion) of the shaft 23. The first bearing 26a is fixed to the lid portion 61. A second bearing 26b is provided at the lower end portion (the output side end portion) of the shaft 23. The second bearing 26b is fixed to the bottom portion 64. The first bearing 26a and the second bearing 26b rotatably support the shaft 23.

[0030] <Power Conversion Device> Next, with reference to FIGS. 2 to 17, the power conversion device 3 will be described. As shown in FIGS. 2, 3, 7, etc., the power conversion device 3 includes a case 31, a terminal block 32 (second external connection portion), a signal connector 33 (first external connection portion), a capacitor unit 34, a control board 36, a plurality of power modules 35 (in this embodiment, six power modules 35U1, 35V1, 35W1, 35U2, 35V2, 35W2), a plurality (in this embodiment, six) of bus bars 37, a plurality (in this embodiment, six) of current sensors 38, and a plurality (in this embodiment, six) of resin members 39.

[0031] The case 31 covers electronic components such as the capacitor unit 34, the power module 35, and the control board 36 from above. Thereby, the insulation between these electronic components and the components mounted around the rotating electrical machine unit 1 is ensured, and foreign matter is prevented from entering from the outside of the rotating electrical machine unit 1.

[0032] The terminal block 32 is provided on the upper surface of the case 31. The terminal block 32 connects the DC power supply E and the capacitor unit 34. The terminal block 32 is a second external connection part that connects the power conversion device 3 and the DC power supply E which is an external power supply. The terminal block 32 has a positive electrode side connection terminal 32a, a negative electrode side connection terminal 32b, and a housing case 32c.

[0033] The positive electrode side connection terminal 32a is connected to the positive electrode power supply terminal of the DC power supply E and the positive electrode conductors 54 of the two capacitor modules 51 of the capacitor unit 34 described later. The negative electrode side connection terminal 32b is connected to the negative electrode power supply terminal of the DC power supply E and the negative electrode conductors 55 of the two capacitor modules 51 of the capacitor unit 34 described later. The housing case 32c houses the positive electrode side connection terminal 32a and the negative electrode side connection terminal 32b.

[0034] As shown in FIG. 3, the upper surface portion of the positive electrode side connection terminal 32a is exposed from the housing case 32c, and the positive electrode power supply terminal of the DC power supply E is connected to this upper surface portion. Both side surfaces in the circumferential direction of the positive electrode side connection terminal 32a are exposed from the housing case 32c, and the positive electrode conductors 54 of the two capacitor modules 51 are respectively connected to these side surfaces. The upper surface portion of the negative electrode side connection terminal 32b is exposed from the housing case 32c, and the negative electrode power supply terminal of the DC power supply E is connected to this upper surface portion. Both side surfaces in the circumferential direction of the negative electrode side connection terminal 32b are exposed from the housing case 32c, and the negative electrode conductors 55 of the two capacitor modules 51 are respectively connected to these side surfaces.

[0035] The signal connector 33 is provided on the upper surface of the case 31. The signal connector 33 is electrically connected to the control board 36. The signal connector 33 is used for passing various signals between the power conversion device 3 and an external control device mounted on a vehicle or the like. The signal connector 33 is a first external connection part that connects the power conversion device 3 and the external control device.

[0036] As shown in FIG. 4, when viewed from the axial direction, the side where the signal connector 33 is arranged with respect to the axis O of the rotor 22 is referred to as the front side, and the opposite side is referred to as the rear side. The signal connector 33 is arranged on the front side of the rotating electrical machine unit 1. The terminal block 32 is arranged on the rear side of the rotating electrical machine unit 1.

[0037] The capacitor unit 34 will be described with reference to FIGS. 7, 8, 12 to 15. As shown in FIG. 8, the capacitor unit 34 is arranged on the outer peripheral portion of the power conversion device 3. When viewed from the axial direction, the capacitor unit 34 extends in the circumferential direction. The capacitor unit 34 is fixed to the lid portion 61.

[0038] The capacitor unit 34 has two capacitor modules 51 arranged in the circumferential direction. One of the two capacitor modules 51 is provided corresponding to half of the six power modules 35 (for example, power modules 35U1, 35V1, 35W1), and the other is provided corresponding to the other half of the power modules 35 (for example, power modules 35U2, 35V2, 35W2). When viewed from the axial direction, each capacitor module 51 has an arc shape extending in the circumferential direction. The two capacitor modules 51 have the same shape. A gap is formed between the ends of the two capacitor modules 51 in the circumferential direction.

[0039] As shown in FIGS. 12 and 13, the capacitor module 51 has a plurality of capacitor elements 52, a housing case 53, a positive electrode conductor 54, and a negative electrode conductor 55.

[0040] The housing case 53 houses a plurality of capacitor elements 52, a part of the positive electrode conductor 54, and a part of the negative electrode conductor 55. In this state, by filling the inside of the housing case 53 with resin, the components housed in the housing case 53 are fixed. In the housing case 53, the capacitor elements 52 are arranged such that the positive electrode is at the lower end and the negative electrode is at the upper end.

[0041] At the lower part of the housing case 53, a plurality of attachment parts 53a for attaching the capacitor module 51 to the lid part 61 are formed. The attachment part 53a is a protrusion that projects radially outward from the outer peripheral surface of the housing case 53. A bolt hole is formed in the attachment part 53a, and by fastening a bolt 53b (see FIG. 8) to this bolt hole, the capacitor module 51 is attached to the lid part 61.

[0042] FIG. 14 is a perspective view of the positive electrode conductor 54. FIG. 15 is a perspective view of the negative electrode conductor 55. The positive electrode conductor 54 and the negative electrode conductor 55 are formed of plate-like members. As the material of the positive electrode conductor 54 and the negative electrode conductor 55, for example, oxygen-free copper is used. In order to reduce the cost of the material, improve the availability, etc., tough pitch copper may be used as the material of the positive electrode conductor 54 and the negative electrode conductor 55. Further, the plate thickness of the positive electrode conductor 54 and the negative electrode conductor 55 is, for example, 0.5 to 2.5 mm.

[0043] The positive electrode conductor 54 is connected to the positive electrode side connection terminal 32a of the terminal block 32 and the positive electrode terminal 35b of the power module 35 described later. The positive electrode conductor 54 has a plurality (three in this embodiment) of first positive electrode end portions 54a, a second positive electrode end portion 54b, a plurality of third positive electrode end portions 54c, a positive electrode side connection portion 54d, and a plurality (three in this embodiment) of positive electrode side cooled portions 54e.

[0044] The three first positive electrode end portions 54a are provided corresponding to the above-mentioned half (three) of the power modules 35 respectively. The first positive electrode end portion 54a is connected to the positive electrode terminal 35b of the corresponding power module 35. The three first positive electrode end portions 54a are arranged at equal intervals (60° intervals) in the circumferential direction. The three first positive electrode end portions 54a have the same shape. The first positive electrode end portion 54a is drawn out from the upper part of the housing case 53. As shown in FIG. 8, the first positive electrode end portion 54a is arranged so as to face the positive electrode terminal 35b of the corresponding power module 35 in the radial direction.

[0045] The second positive electrode end portion 54b is connected to the positive electrode side connection terminal 32a of the terminal block 32. The second positive electrode end portion 54b is drawn out from the upper part of the housing case 53. As shown in FIG. 3, the second positive electrode end portion 54b is arranged to face the side surface of the positive electrode side connection terminal 32a. A bolt hole is formed at the tip of the second positive electrode end portion 54b, and by fastening a bolt 54f to this bolt hole, the second positive electrode end portion 54b is fixed to the side surface of the positive electrode side connection terminal 32a.

[0046] The plurality of third positive electrode end portions 54c are provided corresponding to the plurality of capacitor elements 52 respectively. The third positive electrode end portion 54c is fixed to the lower end portion of the capacitor element 52, for example, by soldering. Thereby, the third positive electrode end portion 54c is connected to the positive electrode provided at the lower end portion of the capacitor element 52. The third positive electrode end portion 54c is housed in the housing case 53.

[0047] The positive electrode side connection portion 54d electrically connects the first positive electrode end portion 54a, the second positive electrode end portion 54b, and the third positive electrode end portion 54c. The positive electrode side connection portion 54d is housed in the housing case 53.

[0048] The positive electrode side connection portion 54d has a plurality of first straight portions 54d1, a plurality of first bending portions 54d2, and a first connection end portion 54d3. The plurality of first straight portions 54d1 are formed, for example, by bending a plate-like member, and are formed to extend substantially in the circumferential direction as a whole. The plurality of first bending portions 54d2 connect the plurality of first straight portions 54d1 to each other. The first connection end portion 54d3 is connected to the first straight portion 54d1 arranged on one side in the circumferential direction, and is bent outward in the radial direction with respect to this first straight portion 54d1.

[0049] The positive electrode conductor 54 is formed by joining a separate first positive electrode end portion 54a, a second positive electrode end portion 54b, and a third positive electrode end portion 54c to the positive electrode side connection portion 54d. The first positive electrode end portion 54a is joined to the upper end portion of the first straight portion 54d1. The second positive electrode end portion 54b is joined to the upper end portion of the first connection end portion 54d3. The third positive electrode end portion 54c is joined to the lower end portion of the first straight portion 54d1.

[0050] The positively - cooled part 54e on the positive - electrode side is provided so as to extend downward from the first positive - electrode end part 54a. The positively - cooled part 54e on the positive - electrode side is integrally formed with the first positive - electrode end part 54a. The positively - cooled part 54e on the positive - electrode side may be formed separately from the first positive - electrode end part 54a. As shown in FIG. 12, the positively - cooled part 54e on the positive - electrode side is arranged inside the condenser module 51 in the radial direction. The positively - cooled part 54e on the positive - electrode side is arranged outside the housing case 53. The positively - cooled part 54e on the positive - electrode side is thermally connected to the cooler 4.

[0051] The negative - electrode conductor 55 is connected to the negative - electrode side connection terminal 32b of the terminal block 32 and the negative - electrode terminal 35c of the power module 35 described later. The negative - electrode conductor 55 has a plurality (three in this embodiment) of first negative - electrode end parts 55a, a second negative - electrode end part 55b, a plurality (three in this embodiment) of third negative - electrode end parts 55c, a negative - electrode side connection part 55d, and a plurality (three in this embodiment) of negatively - cooled parts 55e.

[0052] The three first negative - electrode end parts 55a are respectively provided corresponding to the above - mentioned half (three) of the power modules 35. The first negative - electrode end part 55a is connected to the negative - electrode terminal 35c of the corresponding power module 35. The three first negative - electrode end parts 55a are arranged at equal intervals (60° intervals) in the circumferential direction. The three first negative - electrode end parts 55a have the same shape. The first negative - electrode end part 55a is drawn out from the upper part of the housing case 53. As shown in FIG. 8, the first negative - electrode end part 55a is arranged so as to face the negative - electrode terminal 35c of the corresponding power module 35 in the radial direction.

[0053] The second negative - electrode end part 55b is connected to the negative - electrode side connection terminal 32b of the terminal block 32. The second negative - electrode end part 55b is drawn out from the upper part of the housing case 53. As shown in FIG. 3, the second negative - electrode end part 55b is arranged so as to face the side surface of the negative - electrode side connection terminal 32b. A bolt hole is formed at the tip of the second negative - electrode end part 55b, and by fastening a bolt 55f to this bolt hole, the second negative - electrode end part 55b is fixed to the side surface of the negative - electrode side connection terminal 32b.

[0054] The plurality of third negative electrode ends 55c are provided corresponding to the plurality of capacitor elements 52 respectively. The third negative electrode end 55c is fixed to the upper end of the capacitor element 52, for example, by soldering. Thereby, the third negative electrode end 55c is connected to the negative electrode provided at the upper end of the capacitor element 52. The third negative electrode end 55c is accommodated in the housing case 53.

[0055] The negative electrode side connection part 55d electrically connects the first negative electrode end 55a, the second negative electrode end 55b, and the third negative electrode end 55c. The negative electrode side connection part 55d is accommodated in the housing case 53.

[0056] The negative electrode side connection part 55d has a plurality of second straight parts 55d1, a plurality of second bent parts 55d2, and a second connection end part 55d3. The plurality of second straight parts 55d1 are formed, for example, by bending a plate-like member, and are formed so as to extend substantially in the circumferential direction as a whole. The plurality of second bent parts 55d2 connect the plurality of second straight parts 55d1 to each other. The second connection end part 55d3 is connected to the second straight part 55d1 arranged on one side in the circumferential direction, and is bent outward in the radial direction with respect to this second straight part 55d1.

[0057] The negative electrode conductor 55 is formed by joining a separate first negative electrode end 55a, a second negative electrode end 55b, and a third negative electrode end 55c to the negative electrode side connection part 55d. The first negative electrode end 55a is joined to the upper end of the second straight part 55d1. The second negative electrode end 55b is joined to the upper end of the second connection end part 55d3. The third negative electrode end 55c is joined to the upper end of the second straight part 55d1.

[0058] The negative electrode side cooled part 55e is provided so as to extend downward from the first negative electrode end 55a. The negative electrode side cooled part 55e is integrally formed with the first negative electrode end 55a. The negative electrode side cooled part 55e may be formed separately from the first negative electrode end 55a. As shown in FIG. 12, the negative electrode side cooled part 55e is arranged inside in the radial direction in the capacitor module 51. The negative electrode side cooled part 55e is arranged outside the housing case 53. The negative electrode side cooled part 55e is thermally connected to the cooler 4.

[0059] Referring to FIGS. 7, 8, and 16, the power module 35 will be described. As shown in FIGS. 7 and 8, the six power modules 35 are arranged at the central part of the power conversion device 3. When viewed from the axial direction, the six power modules 35 are surrounded by the capacitor unit 34 from the outside in the radial direction. The six power modules 35 are arranged at equal intervals (60° intervals) in the circumferential direction. The power modules 35U1, 35V1, 35W1, 35U2, 35V2, and 35W2 are arranged in this order in the circumferential direction. Therefore, the power modules 35 of the same phase (for example, the power modules 35U1 and 35U2 of the U1 phase and the U2 phase) are arranged to face each other in the radial direction.

[0060] As shown in FIG. 16, each power module 35 has a main body part 35a, a positive electrode terminal 35b, a negative electrode terminal 35c, an output terminal 35d, a signal terminal 35e on the upper arm side, and a signal terminal 35f on the lower arm side. The power module 35 is fixed to the plate 41 of the cooler 4 described later.

[0061] The main body part 35a has a substantially rectangular shape when viewed from the axial direction. The main body part 35a includes a switching element SW1 and a diode D1 on the upper arm side, and a switching element SW2 and a diode D2 on the lower arm side. At the corner of the main body part 35a, a protrusion 35a1 for fixing the signal terminal 35e on the upper arm side is provided.

[0062] The positive electrode terminal 35b, the negative electrode terminal 35c, the output terminal 35d, the signal terminal 35e on the upper arm side, and the signal terminal 35f on the lower arm side are plate-like members. As materials for the positive electrode terminal 35b, the negative electrode terminal 35c, the output terminal 35d, the signal terminal 35e on the upper arm side, and the signal terminal 35f on the lower arm side, for example, oxygen-free copper is used. In order to reduce the cost of materials, improve the availability, etc., tough pitch copper may be used as the materials for the positive electrode terminal 35b, the negative electrode terminal 35c, the output terminal 35d, the signal terminal 35e on the upper arm side, and the signal terminal 35f on the lower arm side. Also, the plate thickness of the positive electrode terminal 35b, the negative electrode terminal 35c, the output terminal 35d, the signal terminal 35e on the upper arm side, and the signal terminal 35f on the lower arm side is, for example, 0.5 to 1.5 mm.

[0063] As shown in FIG. 8, the positive electrode terminal 35b is arranged to face the first positive electrode end portion 54a. The positive electrode terminal 35b is directly connected to the first positive electrode end portion 54a. Note that being directly connected means that the positive electrode terminal 35b and the first positive electrode end portion 54a are connected by contacting each other without using a wire or the like. For the connection between the positive electrode terminal 35b and the first positive electrode end portion 54a, for example, resistance welding, ultrasonic bonding, TIG welding, laser welding is used. When viewed from the axial direction, the connection portion between the first positive electrode end portion 54a and the positive electrode terminal 35b is located between the housing case 53 and the main body portion 35a.

[0064] The negative electrode terminal 35c is arranged to face the first negative electrode end portion 55a. The negative electrode terminal 35c is directly connected to the first negative electrode end portion 55a. Note that being directly connected means that the negative electrode terminal 35c and the first negative electrode end portion 55a are connected by contacting each other without using a wire or the like. For the connection between the negative electrode terminal 35c and the first negative electrode end portion 55a, for example, resistance welding, ultrasonic bonding, TIG welding, laser welding is used. When viewed from the axial direction, the connection portion between the first negative electrode end portion 55a and the negative electrode terminal 35c is located between the housing case 53 and the main body portion 35a.

[0065] In the present embodiment, the capacitor unit 34 and the power module 35 are provided such that the lengths of the paths from the positive electrode conductor 54 of the capacitor unit 34 to the negative electrode conductor 55 of the capacitor unit 34 via the positive electrode terminal 35b and the negative electrode terminal 35c of the power module 35 are substantially the same in all the power modules 35. That is, the lengths of the connection paths between the capacitor unit 34 and the power module 35 are substantially the same in all the power modules 35. Here, the fact that the lengths of the above paths are substantially the same means that the difference in the lengths of the above paths between each power module 35 is within the range of ±5% with respect to the total length of the path from the positive electrode conductor 54 to the negative electrode conductor 55 via the positive electrode terminal 35b and the negative electrode terminal 35c. Thereby, the surge voltages generated in the respective power modules 35 can be equalized. Therefore, it becomes possible to input a large-capacity current to the power module 35, and it becomes possible to increase the output of the rotating electrical machine unit 1.

[0066] In the present disclosure, it is sufficient that the lengths of the connection paths between the capacitor unit 34 and the power module 35 are substantially the same for at least two power modules 35. Even in this case, the surge voltages generated in these two power modules 35 can be equalized. Therefore, it becomes possible to input a large-capacity current to the power module 35, and it becomes possible to increase the output of the rotating electrical machine unit 1.

[0067] Further, the positive electrode terminal 35b is directly connected to the first positive electrode end portion 54a, and the negative electrode terminal 35c is directly connected to the first negative electrode end portion 55a. That is, the capacitor unit 34 and the power module 35 are connected by the shortest path. Thereby, the inductance of the connection path between the capacitor unit 34 and the power module 35 can be reduced, and the surge voltage generated in the power module 35 can be suppressed. Therefore, it becomes possible to input a larger-capacity current to the power module 35, and it becomes possible to further increase the output of the rotating electrical machine unit 1.

[0068] The output terminal 35d is connected to the coil terminal 25a of the coil 25 via the bus bar 37. In all the power modules 35, the output terminals 35d are arranged to be line-symmetrical with respect to an imaginary line passing through the axis O and the intermediate position of the gap between the positive terminal 35b and the negative terminal 35c. That is, the output terminals 35d are arranged such that when viewed from the radial direction, the center position of the output terminals 35d coincides with the intermediate position of the gap between the positive terminal 35b and the negative terminal 35c. Thereby, in all the power modules 35, the wiring resistance of the connection paths from the positive conductor 54 to the coil terminal 25a and from the negative conductor 55 to the coil terminal 25a becomes uniform. Therefore, it is possible to prevent the current flowing through the power modules 35 from being biased among the plurality of power modules 35.

[0069] The signal terminal 35e on the upper arm side is connected to the switching element SW1 and the diode D1 on the upper arm side. The signal terminal 35f on the lower arm side is connected to the switching element SW2 and the diode D2 on the lower arm side. The signal terminal 35e on the upper arm side and the signal terminal 35f on the lower arm side are connected to the control board 36. As shown in FIG. 3, the signal terminal 35e on the upper arm side and the signal terminal 35f on the lower arm side are directly attached to the control board 36.

[0070] Referring to FIGS. 8, 16, and 17, the bus bar 37 will be described. Each bus bar 37 connects the corresponding-phase power module 35 and the coil 25. As shown in FIG. 8, the bus bar 37 is arranged between the power modules 35 adjacent to each other in the circumferential direction.

[0071] As shown in FIG. 17, the bus bar 37 is a plate-like member. As the material of the bus bar 37, for example, oxygen-free copper is used. As the material of the bus bar 37, tough pitch copper may be used for cost reduction of the material, improvement of availability, etc. The plate thickness of the bus bar 37 is, for example, 0.5 to 2.5 mm.

[0072] The bus bar 37 has a first terminal 37a connected to the output terminal 35d and a second terminal 37b connected to the coil terminal 25a.

[0073] The first terminal 37a is provided at one end of the bus bar 37. As shown in FIG. 16, the first terminal 37a is arranged to face the output terminal 35d. The first terminal 37a is directly connected to the output terminal 35d. Note that being directly connected means that the first terminal 37a and the output terminal 35d are connected by contacting each other without using a wire or the like. For the connection between the first terminal 37a and the output terminal 35d, for example, resistance welding, ultrasonic bonding, TIG welding, or laser welding is used. As shown in FIG. 8, when viewed from the axial direction, the connection portion between the first terminal 37a and the output terminal 35d is located radially inside the main body portion 35a.

[0074] The second terminal 37b is provided at the other end of the bus bar 37. As shown in FIG. 16, the second terminal 37b is arranged to face the coil terminal 25a. The second terminal 37b is directly connected to the coil terminal 25a. Note that being directly connected means that the second terminal 37b and the coil terminal 25a are connected by contacting each other without using a wire or the like. For the connection between the second terminal 37b and the coil terminal 25a, for example, resistance welding, ultrasonic bonding, TIG welding, or laser welding is used. As shown in FIG. 8, when viewed from the axial direction, the connection portion between the second terminal 37b and the coil terminal 25a is located radially outside the main body portion 35a.

[0075] A notch portion 37c is formed in the bus bar 37. The notch portion 37c is formed so as to notch a region of the bus bar 37 that faces the signal terminal 35f on the lower arm side of the power module 35. The notch portion 37c is provided to form a gap between the bus bar 37 and the signal terminal 35f on the lower arm side. For example, the notch portion 37c is formed so that the bus bar 37 and the signal terminal 35f on the lower arm side are separated by 2.0 to 5.0 mm. Thereby, the insulation between the bus bar 37 and the signal terminal 35f on the lower arm side can be ensured.

[0076] A fixing through hole 37d is formed in the bus bar 37. As shown in FIG. 16, a fixing post 41g attached to the plate 41 is inserted into the fixing through hole 37d.

[0077] Each bus bar 37 is provided with a current sensor 38. The bus bar 37 is inserted into the inner space of the core of the current sensor 38. The current sensor 38 detects the current flowing through the bus bar 37. The current sensor 38 has a signal terminal 38a connected to the control board 36. The detection result of the current sensor 38 is output from the signal terminal 38a to the control board 36. As shown in FIG. 3, the signal terminal 38a is directly attached to the control board 36. Thereby, the noise resistance is improved, and the detection accuracy of the current value of the bus bar 37 by the current sensor 38 is improved.

[0078] As shown in FIG. 16, the bus bar 37 and the current sensor 38 are covered with a resin member 39. Note that the signal terminal 38a is exposed from the resin member 39. The resin member 39 integrally holds the bus bar 37 and the current sensor 38. As the material of the resin member 39, for example, polyphenylene sulfide (PPS) is used. The resin member 39 is fixed to the plate 41 together with the control board 36 by bolts 41f3 (see FIG. 4).

[0079] The control board 36 will be described with reference to FIGS. 3 and 4. The control board 36 has a polygonal shape. The control board 36 is disposed at the central portion of the power conversion device 3. As shown in FIG. 4, when viewed from the axial direction, the control board 36 is surrounded by the capacitor unit 34 from the radially outer side. The control board 36 is fixed to the plate 41 by bolts 41f1 and 41f3.

[0080] On the control board 36, the signal terminal 35e on the upper arm side, the signal terminal 35f on the lower arm side, and the signal terminal 38a are directly connected. The signal connector 33 is connected to the control board 36 via a signal connector plug. A harness insertion hole 36a through which the resolver harness 27c is inserted is formed in the central portion of the control board 36. The detection result of the resolver 27 is input to the control board 36 via the resolver harness 27c. The control board 36 controls the power module 35 based on a control command input from an external control device mounted on a vehicle or the like.

[0081] <Cooler> With reference to FIGS. 5, 6, 9, 11, 19 to 21 and the like, the cooler 4 will be described. The cooler 4 cools the power conversion device 3. As shown in FIG. 5, the cooler 4 is disposed inside the capacitor module 51 (capacitor unit 34) in the radial direction. The cooler 4 is fixed to the lid portion 61. FIG. 19 is a perspective view of the cooler 4 and the rotating electric machine 2. As shown in FIG. 19, the cooler 4 includes a plate 41, a base 42, a refrigerant inlet portion 43, a first heat radiating member 44 (bus bar heat radiating member), and a second heat radiating member 45 (capacitor heat radiating member).

[0082] FIGS. 20A and 20B are perspective views of the plate 41. As shown in FIGS. 20A and 20B, the plate 41 is a substantially polygonal plate-like member. For example, the material of the plate 41 is aluminum. The material of the plate 41 may be appropriately changed. The power module 35 is attached to the first surface 41a of the plate 41. The power module 35 is fixed to the first surface 41a of the plate 41 by soldering, for example. The power module 35 is thermally connected to the plate 41.

[0083] As shown in FIG. 20A, a bottomed first mounting hole 41h1, a second mounting hole 41h2, and a third mounting hole 41h3 are provided in the first surface 41a of the plate 41.

[0084] In the first mounting hole 41h1, a fixing post 41g (see FIG. 8) for fixing the control board 36 to the plate 41 is attached. The upper end of the fixing post 41g abuts against the lower surface of the control board 36. In this state, the control board 36 and the fixing post 41g are fixed with bolts 41f1 (see FIG. 4), whereby the control board 36 is fixed to the plate 41. Further, as shown in FIG. 16, a fixing through-hole 37d formed in the bus bar 37 is inserted through the fixing post 41g, whereby the bus bar 37 is fixed to the plate 41.

[0085] In the second mounting hole 41h2, a bolt 41f2 (see FIG. 8) for fixing the resin member 39 to the plate 41 is attached.

[0086] In the third mounting hole 41h3, a bolt 41f3 (see FIG. 4) for fixing the control board 36 and the resin member 39 to the plate 41 is attached. The upper end of the resin member 39 abuts against the lower surface of the control board 36. In this state, the control board 36, the resin member 39, and the plate 41 are fastened with the bolt 41f3, whereby the control board 36 and the resin member 39 are fixed to the plate 41.

[0087] As shown in FIG. 20B, heat-radiating fins 41c are provided on the second surface 41b of the plate 41. As shown in FIG. 11, the heat-radiating fins 41c are arranged at positions overlapping the power module 35 in the axial direction. The second surface 41b of the plate 41 is fixed to the base 42.

[0088] A harness through-hole 41d (insertion hole) through which the resolver harness 27c is inserted is formed in the plate 41. A coil groove portion 41e where the coil terminal 25a is arranged is formed on the outer peripheral surface of the plate 41. Six coil groove portions 41e are arranged at equal intervals (60° intervals) in the circumferential direction.

[0089] As shown in FIG. 19, a first heat radiating member 44 is provided on the first surface 41a of the plate 41. The first heat radiating member 44 has a hexagonal shape. As shown in FIG. 11, the first heat radiating member 44 is disposed between the plate 41 and the bus bar 37. The bus bar 37 is thermally connected to the plate 41 via the first heat radiating member 44.

[0090] FIG. 21 is a perspective view of the base 42 and the refrigerant inlet portion 43. As shown in FIG. 21, the base 42 has a substantially polygonal shape having a first surface 42a, a second surface, and a plurality of side surfaces. For example, the material of the base 42 is aluminum. The material of the base 42 may be changed as appropriate. As shown in FIG. 11, the base 42 is surrounded by the capacitor module 51 (capacitor unit 34) from the outside in the radial direction. The side surface of the base 42 faces the capacitor module 51 in the radial direction. The plate 41 is fixed to the first surface 42a of the base 42. The second surface of the base 42 is fixed to the lid portion 61.

[0091] A harness through hole 42b (insertion hole) through which the resolver harness 27c is inserted is formed in the central portion of the base 42. A coil groove portion 42c extending in the axial direction is formed on the side surface of the base 42. As shown in FIG. 19, the coil terminal 25a is disposed in the coil groove portion 42c. Six coil groove portions 42c are formed at equal intervals (60° intervals) in the circumferential direction. The coil groove portion 42c is filled with a filler 49 having thermal conductivity. The coil terminal 25a is fixed to the coil groove portion 42c by the filler 49. The coil terminal 25a is thermally connected to the base 42 via the filler 49. By discharging the heat generated at the coil terminal 25a to the base 42 via the filler 49, the coil 25 can be cooled.

[0092] A capacitor cooling portion 42e for cooling the capacitor module 51 is provided on the side surface of the base 42. As shown in FIG. 19, a second heat radiating member 45 is provided in the capacitor cooling portion 42e. The second heat radiating member 45 has a rectangular shape.

[0093] As shown in FIG. 6, the second heat radiating member 45 is provided so as to face the positive electrode side cooled portion 54e of the positive electrode conductor 54 and the negative electrode side cooled portion 55e of the negative electrode conductor 55 in the radial direction. The positive electrode side cooled portion 54e and the negative electrode side cooled portion 55e are in contact with the second heat radiating member 45 and are thermally connected to the capacitor cooling portion 42e via the second heat radiating member 45.

[0094] Returning to FIG. 19, the refrigerant inlet portion 43 is attached to the side surface of the base 42. The refrigerant inlet portion 43 is provided so as to project radially outward from the base 42. The refrigerant inlet portion 43 is integrally formed with the base 42. A flow path through which the refrigerant flows is formed inside the refrigerant inlet portion 43. The refrigerant inlet portion 43 is connected to a first joint 46 to which the refrigerant is supplied from the outside. The refrigerant inlet portion 43 and the first joint 46 are arranged on the front side of the rotating electric machine unit 1.

[0095] A first cooling flow path through which the refrigerant flows is formed in the cooler 4. As the refrigerant, for example, water (cooling water) is used. As shown in FIG. 21, the first cooling flow path has an inlet flow path P1, a first flow path P2, a second flow path P3, and an outlet flow path P4. The refrigerant is supplied to the inlet flow path P1 from the first joint 46. The first flow path P2 and the second flow path P3 branch off from the inlet flow path P1. The first flow path P2 is formed at a position overlapping half of the six power modules 35 (specifically, power modules 35U1, 35V1, 35W1) when viewed in the axial direction. The first flow path P2 extends from the inlet flow path P1 to one side in the circumferential direction. The second flow path P3 is formed at a position overlapping the other half of the six power modules 35 (specifically, power modules 35U2, 35V2, 35W2) when viewed in the axial direction. The second flow path P3 extends from the inlet flow path P1 to the other side in the circumferential direction. The outlet flow path P4 is where the refrigerant from the first flow path P2 and the second flow path P3 merges. The outlet flow path P4 communicates with a second cooling flow path formed inside the second cooling portion 65.

[0096] A refrigerant supply port 42f, an annular groove portion 42g, and a refrigerant discharge port 42h are provided in the base 42.

[0097] The refrigerant supply port 42f is a hole that penetrates the peripheral wall of the base 42 in the radial direction. A refrigerant inlet portion 43 is connected to one end of the refrigerant supply port 42f. The other end of the refrigerant supply port 42f is connected to an annular groove portion 42g. The refrigerant inlet portion 43 and the refrigerant supply port 42f are used as an inlet flow path P1.

[0098] The refrigerant discharge port 42h is a hole that penetrates the peripheral wall of the base 42 in the radial direction. The refrigerant discharge port 42h is arranged on the side opposite to the refrigerant supply port 42f in the circumferential direction. One end of the refrigerant discharge port 42h is connected to the annular groove portion 42g. The other end of the refrigerant discharge port 42h is connected to a relay joint 47. The relay joint 47 connects the refrigerant discharge port 42h and an opening 62c of an inner cylinder portion 62 described later. The refrigerant discharge port 42h and the relay joint 47 are used as an outlet flow path P4.

[0099] As shown in FIG. 8, the refrigerant inlet portion 43 is arranged in the front-side gap among two gaps between the ends of the capacitor module 51 in the circumferential direction. The refrigerant discharge port 42h and the relay joint 47 are arranged in the rear-side gap among two gaps between the ends of the capacitor module 51 in the circumferential direction. That is, at least a part of the inlet flow path P1 and at least a part of the outlet flow path P4 are arranged between the ends of the capacitor module 51 in the circumferential direction. The outlet flow path P4 is arranged on the side opposite to the inlet flow path P1 in the radial direction with the axis O interposed therebetween.

[0100] The annular groove portion 42g is formed on the first surface 42a of the base 42. The annular groove portion 42g extends in the circumferential direction and is annular when viewed from the axial direction. The annular groove portion 42g is formed avoiding the harness through hole 42b. The refrigerant supply port 42f and the refrigerant discharge port 42h open to the radially outer side surface of the annular groove portion 42g.

[0101] The annular groove portion 42g has a first groove portion 42g1 which is a portion on one side sandwiched between the refrigerant supply port 42f and the refrigerant discharge port 42h, and a second groove portion 42g2 which is a portion on the other side sandwiched between the refrigerant supply port 42f and the refrigerant discharge port 42h. The first groove portion 42g1 is provided below half of the six power modules 35 (specifically, the power modules 35U1, 35V1, 35W1). The second groove portion 42g2 is provided below the other half of the six power modules 35 (specifically, the power modules 35U2, 35V2, 35W2).

[0102] The first flow path P2 is formed by the first groove portion 42g1 and the second surface 41b of the plate 41. The second flow path P3 is formed by the second groove portion 42g2 and the second surface 41b of the plate 41. As shown in FIG. 11, the heat dissipation fins 41c are arranged inside the annular groove portion 42g (that is, in the first flow path P2 or the second flow path P3).

[0103] The refrigerant supplied from the first joint 46 is branched into the first flow path P2 and the second flow path P3 through the inlet flow path P1. The heat generated in the power modules 35U1, 35V1, 35W1 is heat-exchanged with the refrigerant flowing through the first flow path P2 via the heat dissipation fins 41c. Thereby, the power modules 35U1, 35V1, 35W1 are cooled. The heat generated in the power modules 35U2, 35V2, 35W2 is heat-exchanged with the refrigerant flowing through the second flow path P3 via the heat dissipation fins 41c. Thereby, the power modules 35U2, 35V2, 35W2 are cooled.

[0104] The positive electrode side cooled portion 54e and the negative electrode side cooled portion 55e of the capacitor module 51 are thermally connected to the capacitor cooling portion 42e via the second heat dissipation member 45. The heat generated in the capacitor module 51 (capacitor element 52) is transmitted to the positive electrode side cooled portion 54e and the negative electrode side cooled portion 55e, and heat-exchanged with the refrigerant flowing through the first flow path P2 and the second flow path P3 via the capacitor cooling portion 42e and the second heat dissipation member 45. Thereby, the capacitor module 51 is cooled.

[0105] The bus bar 37 is thermally connected to the plate 41 via the first heat dissipation member 44. The heat generated in the bus bar 37 is heat-exchanged with the refrigerant flowing through the first flow path P2 and the second flow path P3 via the first heat dissipation member 44 and the plate 41. Thereby, the bus bar 37 is cooled.

[0106] Thereafter, the refrigerant from the first flow path P2 and the second flow path P3 merges at the outlet flow path P4 and is discharged toward the second cooling unit 65.

[0107] <Second Cooling Unit> The second cooling unit 65 will be described with reference to FIGS. 9 and 22. As shown in FIG. 9, the second cooling unit 65 is constituted by an inner cylinder portion 62 and an outer cylinder portion 63. A second cooling flow path through which the refrigerant flows is formed in the second cooling unit 65. The second cooling flow path is formed between the outer peripheral surface of the inner cylinder portion 62 and the inner peripheral surface of the outer cylinder portion 63.

[0108] FIGS. 22A and 22B are perspective views of the inner cylinder portion 62. As shown in FIGS. 22A and 22B, the inner cylinder portion 62 has a cylindrical main body portion 62a and a flange portion 62b that projects radially outward from the upper end of the main body portion 62a. An opening 62c is formed in the flange portion 62b. As shown in FIG. 9, the refrigerant discharge port 42h and the opening 62c are connected by a relay joint 47.

[0109] The second cooling flow path has a communication flow path P5, a third flow path P6, a fourth flow path P7, and a discharge flow path P8. The communication flow path P5 communicates with the outlet flow path P4. The third flow path P6 and the fourth flow path P7 branch off from the communication flow path P5. The third flow path P6 extends from the communication flow path P5 to one side in the circumferential direction. The fourth flow path P7 extends from the communication flow path P5 to the other side in the circumferential direction. The discharge flow path P8 is where the refrigerant from the third flow path P6 and the fourth flow path P7 merges. The refrigerant is discharged to the outside from the discharge flow path P8.

[0110] On the outer peripheral surface of the main body portion 62a, a first groove portion 62d, a second groove portion 62e, a third groove portion 62f, and a fourth groove portion 62g are formed.

[0111] The first groove portion 62d is formed below the opening portion 62c. The first groove portion 62d extends in the axial direction. The upper end of the first groove portion 62d communicates with the opening portion 62c. The lower end of the first groove portion 62d is closed. The inner peripheral surface of the outer cylinder portion 63 and the first groove portion 62d form a communication flow path P5.

[0112] The second groove portion 62e is formed on the opposite side in the circumferential direction to the first groove portion 62d. The second groove portion 62e extends in the axial direction. The upper end and the lower end of the second groove portion 62e are closed. The second groove portion 62e and the inner peripheral surface of the outer cylinder portion 63 form a discharge flow path P8.

[0113] The third groove portion 62f is connected to the first groove portion 62d and the second groove portion 62e. The third groove portion 62f extends to one side in the circumferential direction from the first groove portion 62d to the second groove portion 62e. A plurality of third groove portions 62f are formed at intervals in the axial direction. The third groove portion 62f and the inner peripheral surface of the outer cylinder portion 63 form a third flow path P6.

[0114] The fourth groove portion 62g is connected to the first groove portion 62d and the second groove portion 62e. The fourth groove portion 62g extends to the other side in the circumferential direction from the first groove portion 62d to the second groove portion 62e. A plurality of fourth groove portions 62g are formed at intervals in the axial direction. The fourth groove portion 62g and the inner peripheral surface of the outer cylinder portion 63 form a fourth flow path P7.

[0115] As shown in FIG. 9, an opening portion 63a that penetrates the peripheral wall of the outer cylinder portion 63 in the radial direction is formed at the lower end portion of the outer cylinder portion 63. The opening portion 63a communicates with the second groove portion 62e. The opening portion 63a is connected to a second joint 48 that discharges the refrigerant to the outside. Note that the second joint 48 is disposed on the front side of the rotating electric machine unit 1.

[0116] The refrigerant discharged from the refrigerant discharge port 42h of the cooler 4 flows into the communication flow path P5 through the relay joint 47 and the opening 62c. The refrigerant flows through the communication flow path P5 from the opening 62c downward in the axial direction (i.e., toward the output side), and is branched into a third flow path P6 and a fourth flow path P7. The refrigerant flowing through the third flow path P6 cools one half of the rotating electrical machine 2 in one circumferential direction. The refrigerant flowing through the fourth flow path P7 cools the other half of the rotating electrical machine 2 in the circumferential direction. Since a plurality of the third flow paths P6 and the fourth flow paths P7 are provided at intervals in the axial direction, the cooling efficiency of the rotating electrical machine 2 by the second cooling portion 65 is improved. Thereafter, the refrigerant from the third flow path P6 and the fourth flow path P7 merges in the discharge flow path P8, flows downward through the discharge flow path P8, and is discharged to the outside through the opening 63a and the second joint 48.

[0117] As described above, the rotating electrical machine unit 1 includes a rotating electrical machine 2, a power conversion device 3, a cooler 4 in which a first cooling flow path through which a refrigerant flows is formed to cool the power conversion device 3. The power conversion device 3 includes a plurality of power modules 35 and a capacitor unit 34. The first cooling flow path includes an inlet flow path P1 to which a refrigerant is supplied, a first flow path P2 that branches from the inlet flow path P1 and is formed at a position overlapping a first group of the plurality of power modules 35 when viewed from the axial direction, a second flow path P3 that branches from the inlet flow path P1 and is formed at a position overlapping a second group of the plurality of power modules 35 different from the first group when viewed from the axial direction, and an outlet flow path P4 into which the refrigerant from the first flow path P2 and the second flow path P3 merges and from which the refrigerant is discharged from the cooler 4. The capacitor unit 34 is arranged so as to surround the cooler 4 from the outside in the radial direction. The cooler 4 can cool the power conversion device 3. Further, the refrigerant is branched and flows through the first flow path P2 and the second flow path P3. Therefore, compared with the case where a plurality of power modules 35 are arranged on a single cooling flow path without branching the cooling flow path, it is possible to suppress the temperature of the refrigerant from being uneven between the upstream side and the downstream side of the cooling flow path. Therefore, a plurality of power modules 35 can be cooled uniformly, and the cooling performance of the rotating electrical machine unit 1 can be improved. As a result, it becomes possible to input a large-capacity current to the power module 35, and it becomes possible to increase the output of the rotating electrical machine unit 1. Furthermore, since the capacitor unit 34 is arranged so as to surround the cooler 4 from the outside in the radial direction, the rotating electrical machine unit 1 can be miniaturized in the axial direction compared to the case where the capacitor unit is arranged above the cooler, for example.

[0118] Also, the plurality of power modules 35 are arranged in the circumferential direction. The first flow path P2 extends from the inlet flow path P1 to one side in the circumferential direction, and the second flow path P3 extends from the inlet flow path P1 to the other side in the circumferential direction. Thereby, a plurality of power modules 35 can be cooled more uniformly and efficiently.

[0119] The rotating electrical machine unit 1 further includes a second cooling unit 65 that forms a second cooling flow path through which the refrigerant flows and cools the rotating electrical machine 2. The second cooling flow path includes a communication flow path P5 that communicates with the outlet flow path P4, a third flow path P6 that branches from the communication flow path P5 and extends from the communication flow path P5 to one side in the circumferential direction, a fourth flow path P7 that branches from the communication flow path P5 and extends from the communication flow path P5 to the other side in the circumferential direction, a discharge flow path P8 in which the refrigerant from the third flow path P6 and the fourth flow path P7 merges and the refrigerant is discharged from the second cooling unit 65. Since the first cooling flow path of the cooler 4 and the second cooling flow path of the second cooling unit 65 communicate with each other within the rotary electric machine unit 1, the rotary electric machine unit 1 can be miniaturized. Further, the refrigerant flowing through the third flow path P6 cools one half of the rotary electric machine 2 in one circumferential direction, and the refrigerant flowing through the fourth flow path P7 cools the other half of the rotary electric machine 2 in the circumferential direction. Therefore, the cooling efficiency of the rotary electric machine 2 by the second cooling unit 65 is improved.

[0120] Also, the cooler 4 has a plurality of heat radiation fins 41c disposed in the first flow path P2 or the second flow path P3. When viewed from the axial direction, the plurality of heat radiation fins 41c are disposed at positions overlapping the plurality of power modules 35. Thereby, the cooling efficiency of the power module 35 by the cooler 4 is improved. As a result, it becomes possible to input a large-capacity current to the power module 35, and it becomes possible to increase the output of the rotary electric machine unit 1.

[0121] The capacitor unit 34 has a positive electrode conductor 54 and a negative electrode conductor 55. The positive electrode conductor 54 has a positive electrode side cooled portion 54e disposed inside the capacitor unit 34 in the radial direction. The negative electrode conductor 55 has a negative electrode side cooled portion 55e disposed inside the capacitor unit 34 in the radial direction. The cooler 4 has a capacitor cooling portion 42e disposed outside the cooler 4 in the radial direction and thermally connected to the positive electrode side cooled portion 54e and the negative electrode side cooled portion 55e. The capacitor unit 34 has a positive electrode side cooled portion 54e and a negative electrode side cooled portion 55e disposed inside the capacitor unit 34 in the radial direction and thermally connected to the capacitor cooling portion 42e. Thereby, the capacitor unit 34 can be cooled from the inner side in the radial direction. Further, for example, compared with the case where the capacitor unit is cooled from the upper side in the axial direction, it is possible to provide a wider area for cooling the capacitor unit 34. As a result, the cooling performance of the capacitor unit 34 by the cooler 4 can be improved, and the output of the rotary electric machine unit 1 can be increased. Further, when the positive electrode conductor 54 and the negative electrode conductor 55 are made of copper with high thermal conductivity, the cooling performance of the capacitor unit 34 is further improved, and the high output of the rotating electrical machine unit 1 can be achieved. Further, in order to cool the capacitor unit 34 by using the positive electrode side cooled portion 54e and the negative electrode side cooled portion 55e which are not current flow paths, the inductance of the connection path between the capacitor unit 34 and the power module 35 does not increase, and the surge voltage generated in the power module 35 can be suppressed. Therefore, a larger current can be input to the power module 35, and further high output of the rotating electrical machine unit 1 can be achieved.

[0122] Further, the cooler 4 has a second heat radiating member 45 provided between the positive electrode side cooled portion 54e and the negative electrode side cooled portion 55e and the capacitor cooling portion 42e. Thereby, the cooling efficiency of the capacitor unit 34 by the cooler 4 is improved.

[0123] Further, the positive electrode conductor 54 has a plurality of positive electrode side cooled portions 54e, the negative electrode conductor 55 has a plurality of negative electrode side cooled portions 55e, and the cooler 4 has a plurality of capacitor cooling portions 42e. Thereby, the cooling performance of the capacitor unit 34 by the cooler 4 is further improved.

[0124] Further, the capacitor unit 34 includes a plurality of capacitor modules 51 arranged in the circumferential direction. Thereby, since a mold or the like for molding each member of the capacitor module 51 can be miniaturized, the manufacturing cost can be reduced. Further, since the capacitor unit 34 can be transported as a plurality of capacitor modules 51, compared with the case where the capacitor unit 34 is formed by one capacitor module, for example, the space of the tray for accommodating the capacitor unit 34 during transportation can be reduced, and the transportation cost can be reduced.

[0125] Further, each of the plurality of capacitor modules 51 has an arc shape when viewed from the axial direction. At least a part of the inlet flow path P1 and at least a part of the outlet flow path P4 are arranged between the ends of the plurality of capacitor modules 51 in the circumferential direction. The outlet flow path P4 is arranged on the radially opposite side of the inlet flow path P1 with respect to the axis O of the rotor 22. Since at least a part of the inlet flow path P1 and at least a part of the outlet flow path P4 are arranged between the ends of the plurality of capacitor modules 51 in the circumferential direction, the size of the rotating electrical machine unit 1 can be reduced. In addition, since the flow direction of the refrigerant in the inlet flow path P1 and the flow direction of the refrigerant in the outlet flow path P4 can be arranged linearly, the pressure loss in the inlet flow path P1 and the outlet flow path P4 can be reduced, and the cooling performance of the cooler 4 can be improved.

[0126] The power conversion device 3 further includes a plurality of bus bars 37 that connect the plurality of power modules 35 and the plurality of coils 25 respectively. Thereby, the power module 35 and the coil 25 can be easily electrically connected using the bus bar 37.

[0127] The cooler 4 further includes a plate 41 to which the plurality of power modules 35 are attached, and a first heat radiating member 44 provided between the plurality of bus bars 37 and the plate 41. The bus bar 37 can be cooled by the cooler 4. Therefore, a larger current can be input to the bus bar 37, and the rotating electrical machine unit 1 can be further increased in output power.

[0128] The cooler 4 is further formed with a plurality of coil grooves 42c in which the plurality of coils 25 are respectively arranged. The plurality of coil grooves 42c are filled with a filler 49 having thermal conductivity. Since the heat generated in the coil 25 is exchanged with the cooler 4 via the filler 49, the coil 25 can be cooled by the cooler 4. Therefore, it becomes possible to input a large-capacity current to the coil 25, and it becomes possible to increase the output of the rotating electrical machine unit 1. Further, the coil 25 can be fixed to the coil groove portion 42c by the filler 49. Therefore, it is possible to suppress the coil 25 from being damaged or an electrical connection failure between the coil 25 and the power module 35 from occurring due to vibration of the rotating electrical machine unit 1, an external force applied to the rotating electrical machine unit 1, etc., and the reliability of the rotating electrical machine unit 1 can be improved.

[0129] In addition, harness through-holes 41d and 42b through which the resolver harness 27c of the resolver 27 is inserted are formed in the central portion of the cooler 4. Since the resolver harness 27c can be arranged at the central portion of the cooler 4, a plurality of power modules 35 can be arranged at equal intervals in the circumferential direction, for example, and the degree of freedom in arranging the power modules 35 is improved. Therefore, for example, the mounting density of the members in the power conversion device 3 can be improved such that a plurality of power modules 35 can be arranged closer to each other, and the rotating electrical machine unit 1 can be miniaturized.

[0130] The capacitor unit 34 has a positive electrode conductor 54 and a negative electrode conductor 55. The power module 35 has a positive electrode terminal 35b and a negative electrode terminal 35c. The length of the first path from the positive electrode conductor 54 to the negative electrode conductor 55 via the positive electrode terminal 35b and the negative electrode terminal 35c of the first power module 35 among the plurality of power modules 35 is substantially the same as the length of the second path from the positive electrode conductor 54 to the negative electrode conductor 55 via the positive electrode terminal 35b and the negative electrode terminal 35c of the second power module 35 among the plurality of power modules 35. Note that the length of the first path being substantially the same as the length of the second path means that the difference between the length of the first path and the length of the second path is within the range of ±5% with respect to the total length of the first path. As a result, the surge voltages generated in the first power module 35 and the second power module 35 can be made equal. Therefore, it becomes possible to input a large-capacity current to the power module 35, and it becomes possible to increase the output of the rotating electrical machine unit 1.

[0131] Also, in all of the plurality of power modules 35, the lengths of the paths from the positive conductor 54 to the negative conductor 55 via the positive terminal 35b and the negative terminal 35c are substantially the same. As a result, for all of the power modules 35, the surge voltages generated in the respective power modules 35 can be made equal. Therefore, it becomes possible to input a larger-capacity current to the power module 35, and it becomes possible to further increase the output of the rotating electrical machine unit 1.

[0132] Also, the cooler 4 is arranged on the rotating electrical machine 2 side rather than the plurality of power modules 35 in the axial direction. As a result, the heat generated from the rotating electrical machine 2 can be blocked by the cooler 4, so that the heat generated from the rotating electrical machine 2 can be prevented from being transmitted to the power module 35. Therefore, it becomes possible to input a large-capacity current to the power module 35, and it becomes possible to increase the output of the rotating electrical machine unit 1.

[0133] Also, the capacitor unit 34 and the cooler 4 face each other in the radial direction. As a result, the cooler 4 can cool the power module 35 in the axial direction and the capacitor unit 34 in the radial direction. Therefore, for example, compared with the case where the capacitor unit is arranged side by side with the cooler in the axial direction, the rotating electrical machine unit 1 can be downsized in the axial direction.

[0134] Embodiment 2. Next, the rotating electrical machine unit 1 according to Embodiment 2 will be described. Since the basic configuration of the rotating electrical machine unit according to this embodiment is the same as that of the rotating electrical machine unit 1 in Embodiment 1, the description will focus on the differences. FIG. 23 is a perspective view of the housing case 53A of the capacitor module 51 according to this embodiment. FIG. 24 is a cross-sectional view of the rotating electrical machine unit 1 according to this embodiment, which is a cross-sectional view taken along line E-E in FIG. 8.

[0135] As shown in FIG. 23, the housing case 53A has a main body portion 531 and a plurality of pressing members 532 fixed to the main body portion 531. The pressing members 532 are provided on the surface facing the inner side in the radial direction of the main body portion 531. The pressing members 532 have elasticity. The upper end portion of the pressing member 532 is fixed to the surface facing the inner side in the radial direction of the main body portion 531. A protrusion protruding inward in the radial direction is provided at the lower end portion of the pressing member 532. The materials of the main body portion 531 and the pressing members 532 are, for example, resin. The main body portion 531 and the pressing members 532 are integrally formed. Note that the pressing members 532 may be attached to the surface facing the inner side in the radial direction of the main body portion 531 using an adhesive.

[0136] As shown in FIG. 24, the positive electrode side cooled portion 54e and the negative electrode side cooled portion 55e are arranged on the inner side in the radial direction of the pressing member 532. More specifically, the main body portion 531, the pressing member 532, the positive electrode side cooled portion 54e or the negative electrode side cooled portion 55e, the second heat radiating member 45, and the base 42 (capacitor cooling portion 42e) are arranged in this order from the outer side to the inner side in the radial direction. The lower end portion of the pressing member 532 abuts against the positive electrode side cooled portion 54e and the negative electrode side cooled portion 55e from the outer side in the radial direction. At this time, the lower end portion of the pressing member 532 is elastically deformed outward in the radial direction. Due to the elastic force of the pressing member 532, the positive electrode side cooled portion 54e and the negative electrode side cooled portion 55e are pressed against the second heat radiating member 45.

[0137] As described above, in the present embodiment, the capacitor unit 34 has a pressing member 532 that presses the positive electrode side cooled portion 54e and the negative electrode side cooled portion 55e against the second heat radiating member 45. As a result, the adhesion between the positive electrode side cooled portion 54e and the negative electrode side cooled portion 55e and the second heat radiating member 45 is improved, so that the cooling performance of the capacitor unit 34 can be improved, and the high output of the rotating electrical machine unit 1 can be achieved.

[0138] Note that the technical scope of the present disclosure is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present disclosure.

[0139] For example, the rotating electrical machine unit 1 may be a rotating electrical machine unit having a multi-phase drive system of six phases or more. The capacitor unit 34 may be configured by only one capacitor module 51. The capacitor unit 34 may have three or more capacitor modules 51.

[0140] Hereinafter, various aspects of the present disclosure will be collectively described as appendices.

[0141] (Appendix 1) A rotating electrical machine having a stator, a rotor that rotates around an axis with respect to the stator, and a plurality of coils wound around the stator, An electric power conversion device arranged side by side with the rotating electrical machine in the axial direction along the axis of the rotor, A first cooling portion that forms a first cooling flow path through which a refrigerant flows and cools the electric power conversion device, Comprising, The electric power conversion device has a plurality of power modules electrically connected to the plurality of coils respectively, and a capacitor unit electrically connected to the plurality of power modules, The first cooling flow path is An inlet flow path to which the refrigerant is supplied, A first flow path that branches from the inlet flow path and is formed at a position overlapping a first group of power modules among the plurality of power modules when viewed from the axial direction, A second flow path that branches from the inlet flow path and is formed at a position overlapping with a second group of power modules different from the first group among the plurality of power modules when viewed from the axial direction; An outlet flow path through which the refrigerant from the first flow path and the second flow path merges and from which the refrigerant is discharged from the first cooling unit; and The capacitor unit is a rotating electrical machine unit arranged to surround the first cooling unit from the outside in the radial direction.

[0142] (Appendix 2) The plurality of power modules are arranged in the circumferential direction around the axis of the rotor, The rotating electrical machine unit according to Appendix 1, wherein the first flow path extends from the inlet flow path to one side in the circumferential direction, and the second flow path extends from the inlet flow path to the other side in the circumferential direction.

[0143] (Appendix 3) A second cooling flow path through which the refrigerant flows is formed, and a second cooling unit for cooling the rotating electrical machine, Further comprising The second cooling flow path A communication flow path communicating with the outlet flow path; A third flow path that branches from the communication flow path and extends to one side in the circumferential direction from the communication flow path; A fourth flow path that branches from the communication flow path and extends to the other side in the circumferential direction from the communication flow path; An exhaust flow path through which the refrigerant from the third flow path and the fourth flow path merges and from which the refrigerant is discharged from the second cooling unit; and The rotating electrical machine unit according to Appendix 1 or 2, having

[0144] (Appendix 4) The first cooling unit has a plurality of heat dissipation fins arranged in the first flow path or the second flow path, The rotating electrical machine unit according to any one of Appendices 1 to 3, wherein when viewed from the axial direction, the plurality of heat dissipation fins are arranged at positions overlapping with the plurality of power modules.

[0145] (Appendix 5) The capacitor unit has a positive electrode conductor and a negative electrode conductor. The positive electrode conductor has a positive electrode side cooled portion disposed inside in the radial direction in the capacitor unit. The negative electrode conductor has a negative electrode side cooled portion disposed inside in the radial direction in the capacitor unit. The first cooling portion has a capacitor cooling portion disposed outside in the radial direction in the first cooling portion and thermally connected to the positive electrode side cooled portion and the negative electrode side cooled portion, and is the rotating electrical machine unit according to any one of Appendices 1 to 4.

[0146] (Appendix 6) The first cooling portion has a capacitor heat dissipation member provided between the positive electrode side cooled portion and the negative electrode side cooled portion and the capacitor cooling portion, and is the rotating electrical machine unit according to Appendix 5.

[0147] (Appendix 7) The positive electrode conductor has a plurality of positive electrode side cooled portions as the positive electrode side cooled portion. The negative electrode conductor has a plurality of negative electrode side cooled portions as the negative electrode side cooled portion. The first cooling portion has a plurality of capacitor cooling portions as the capacitor cooling portion, and is the rotating electrical machine unit according to Appendix 5 or 6.

[0148] (Appendix 8) The capacitor unit includes a plurality of capacitor modules arranged in the circumferential direction, and is the rotating electrical machine unit according to any one of Appendices 1 to 7.

[0149] (Appendix 9) Each of the plurality of capacitor modules has an arc shape when viewed from the axial direction. At least a part of the inlet flow path and at least a part of the outlet flow path are arranged between ends in the circumferential direction of the plurality of capacitor modules. The rotary electric machine unit according to appended note 8, wherein the outlet flow path is disposed on the side opposite to the inlet flow path in the radial direction with respect to the axis of the rotor.

[0150] (Appended note 10) The rotary electric machine unit according to any one of appended notes 1 to 9, wherein the power conversion device further includes a plurality of bus bars that connect the plurality of power modules and the plurality of coils respectively.

[0151] (Appended note 11) The rotary electric machine unit according to appended note 10, wherein the first cooling unit further includes a plate to which the plurality of power modules are attached, and a bus bar heat dissipation member provided between the plurality of bus bars and the plate.

[0152] (Appended note 12) A plurality of coil grooves in which the plurality of coils are respectively disposed are formed in the first cooling unit. The rotary electric machine unit according to any one of appended notes 1 to 11, wherein the plurality of coil grooves are filled with a filler having thermal conductivity.

[0153] (Appended note 13) The rotary electric machine further includes a resolver that is disposed between the stator and the power module and detects the rotation angle of a shaft disposed at the center of the rotor. The rotary electric machine unit according to any one of appended notes 1 to 12, wherein an insertion hole through which a signal line of the resolver is inserted is formed in the central portion of the first cooling unit.

[0154] (Appended note 14) The capacitor unit has a positive electrode conductor and a negative electrode conductor. Each of the plurality of power modules has a positive electrode terminal connected to the positive electrode conductor and a negative electrode terminal connected to the negative electrode conductor. The length of a first path from the positive electrode conductor to the negative electrode conductor via the positive electrode terminal and the negative electrode terminal of a first power module among the plurality of power modules is substantially the same as the length of a second path from the positive electrode conductor to the negative electrode conductor via the positive electrode terminal and the negative electrode terminal of a second power module among the plurality of power modules. The rotating electrical machine unit according to any one of Supplementary Notes 1 to 13.

[0155] (Supplementary Note 15) In all of the plurality of power modules, the length of the path from the positive electrode conductor to the negative electrode conductor via the positive electrode terminal and the negative electrode terminal is substantially the same. The rotating electrical machine unit according to Supplementary Note 14.

[0156] (Supplementary Note 16) The first cooling part is arranged closer to the rotating electrical machine side than the plurality of power modules in the axial direction. The rotating electrical machine unit according to any one of Supplementary Notes 1 to 15.

[0157] (Supplementary Note 17) The capacitor unit and the first cooling part face each other in the radial direction. The rotating electrical machine unit according to any one of Supplementary Notes 1 to 16.

[0158] (Supplementary Note 18) The capacitor unit has a pressing member that presses the positive electrode side cooled part and the negative electrode side cooled part against the capacitor heat radiating member. The rotating electrical machine unit according to Supplementary Note 6 or 7.

Explanation of Signs

[0159] 1 Rotating electrical machine unit 2 Rotating electrical machine 3 Power conversion device 21 Stator 22 Rotor 23 Shaft 25 Coil 27 Resolver 34 Capacitor unit 35 Power module 35b Positive terminal 35c Negative terminal 37 Bus bar 41 Plate 41c Heat dissipation fin 42 Base 42c Coil groove portion 42e Capacitor cooling portion 44 First heat dissipation member (bus bar heat dissipation member) 45 Second heat dissipation member (capacitor heat dissipation member) 51 Capacitor module 54 Positive conductor 54e Positively cooled portion 55 Negative conductor 55e Negatively cooled portion 65 Second cooling portion 532 Pressing member O Axis center P1 Inlet flow path P2 First flow path P3 Second flow path P4 Outlet flow path P5 Communication flow path P6 Third flow path P7 Fourth flow path P8 Discharge flow path

Claims

1. A rotating electrical machine having a stator, a rotor that rotates about an axis with respect to the stator, and a plurality of coils wound around the stator; A power conversion device arranged side by side with the rotating electrical machine in an axial direction along the axis of the rotor; A first cooling unit in which a first cooling flow path through which a refrigerant flows is formed to cool the power conversion device; Comprising: The power conversion device has a plurality of power modules electrically connected to the plurality of coils respectively, and a capacitor unit electrically connected to the plurality of power modules; The first cooling flow path is An inlet flow path through which the refrigerant is supplied; A first flow path that branches from the inlet flow path and is formed at a position overlapping a first group of power modules among the plurality of power modules when viewed in the axial direction; A second flow path that branches from the inlet flow path and is formed at a position overlapping a second group of power modules different from the first group among the plurality of power modules when viewed in the axial direction; An outlet flow path through which the refrigerant from the first flow path and the second flow path merges and the refrigerant is discharged from the first cooling unit; The capacitor unit is arranged so as to surround the first cooling unit from the radially outer side, a rotating electrical machine unit.

2. The plurality of power modules are arranged in a circumferential direction around the axis of the rotor, The first flow path extends from the inlet flow path to one side in the circumferential direction, and the second flow path extends from the inlet flow path to the other side in the circumferential direction, the rotating electrical machine unit according to Claim 1.

3. A second cooling unit in which a second cooling flow path through which a refrigerant flows is formed to cool the rotating electrical machine, Further comprising: The second cooling flow path is A communication flow path communicating with the outlet flow path; A third flow path that branches from the communication flow path and extends to one side in the circumferential direction from the communication flow path; A fourth flow path that branches from the communication flow path and extends to the other side in the circumferential direction from the communication flow path; An exhaust flow path through which the refrigerant from the third flow path and the fourth flow path merges and the refrigerant is discharged from the second cooling unit; Having, the rotating electrical machine unit according to Claim 1 or 2.

4. The first cooling unit has a plurality of heat radiation fins arranged in the first flow path or the second flow path, The rotating electrical machine unit according to claim 1 or 2, wherein when viewed from the axial direction, the plurality of heat radiating fins are arranged at positions overlapping the plurality of power modules.

5. The capacitor unit has a positive electrode conductor and a negative electrode conductor. The positive electrode conductor has a positive electrode side cooled portion disposed inside the capacitor unit in the radial direction. The negative electrode conductor has a negative electrode side cooled portion disposed inside the capacitor unit in the radial direction. The rotating electrical machine unit according to claim 1, wherein the first cooling portion has a capacitor cooling portion disposed outside the first cooling portion in the radial direction and thermally connected to the positive electrode side cooled portion and the negative electrode side cooled portion.

6. The rotating electrical machine unit according to claim 5, wherein the first cooling portion has a capacitor heat radiating member provided between the positive electrode side cooled portion, the negative electrode side cooled portion, and the capacitor cooling portion.

7. The positive electrode conductor has a plurality of positive electrode side cooled portions as the positive electrode side cooled portion. The negative electrode conductor has a plurality of negative electrode side cooled portions as the negative electrode side cooled portion. The rotating electrical machine unit according to claim 5 or 6, wherein the first cooling portion has a plurality of capacitor cooling portions as the capacitor cooling portion.

8. The rotating electrical machine unit according to claim 1 or 2, wherein the capacitor unit includes a plurality of capacitor modules arranged in the circumferential direction.

9. Each of the plurality of capacitor modules has an arc shape when viewed from the axial direction. At least a part of the inlet flow path and at least a part of the outlet flow path are arranged between ends of the plurality of capacitor modules in the circumferential direction. The rotating electrical machine unit according to claim 8, wherein the outlet flow path is arranged on the opposite side in the radial direction to the inlet flow path with respect to the axis of the rotor.

10. The rotating electrical machine unit according to claim 1 or 2, wherein the power conversion device further has a plurality of bus bars connecting the plurality of power modules and the plurality of coils respectively.

11. The rotating electrical machine unit according to claim 10, wherein the first cooling portion further has a plate to which the plurality of power modules are attached and a bus bar heat radiating member provided between the plurality of bus bars and the plate.

12. A plurality of coil grooves in which the plurality of coils are respectively arranged are formed in the first cooling portion. The rotating electrical machine unit according to claim 1 or 2, wherein the plurality of coil grooves are filled with a filler having thermal conductivity.

13. The rotating electrical machine further includes a resolver disposed between the stator and the power module and detecting a rotation angle of a shaft disposed at the center of the rotor. The rotating electrical machine unit according to claim 1 or 2, wherein an insertion hole through which a signal line of the resolver is inserted is formed in a central portion of the first cooling portion.

14. The capacitor unit has a positive electrode conductor and a negative electrode conductor. Each of the plurality of power modules has a positive electrode terminal connected to the positive electrode conductor and a negative electrode terminal connected to the negative electrode conductor. The length of a first path from the positive electrode conductor to the negative electrode conductor via the positive electrode terminal and the negative electrode terminal of a first power module among the plurality of power modules is substantially the same as the length of a second path from the positive electrode conductor to the negative electrode conductor via the positive electrode terminal and the negative electrode terminal of a second power module among the plurality of power modules. The rotating electrical machine unit according to claim 1 or 2.

15. The rotating electrical machine unit according to claim 14, wherein in all of the plurality of power modules, the lengths of paths from the positive electrode conductor to the negative electrode conductor via the positive electrode terminal and the negative electrode terminal are substantially the same.

16. The rotating electrical machine unit according to claim 1 or 2, wherein the first cooling portion is disposed closer to the rotating electrical machine side than the plurality of power modules in the axial direction.

17. The rotating electrical machine unit according to claim 1 or 2, wherein the capacitor unit and the first cooling portion face each other in the radial direction.

18. The rotating electrical machine unit according to claim 6, wherein the capacitor unit has a pressing member that presses the positive electrode side cooled portion and the negative electrode side cooled portion against the capacitor heat radiating member.

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