Rotating Electric Unit

Abstract

A rotating electric machine unit according to the present disclosure comprises: a rotating electric machine that has a stator, a rotor that rotates about a central axis relative to the stator, and a plurality of coils that are wound around the stator; and an electric power conversion device that is located next to the rotating electric machine in the axial direction along the central axis of the rotor. The electric power conversion device has a plurality of power modules that are respectively electrically connected to the plurality of coils, and a capacitor unit that is electrically connected to the plurality of power modules, the capacitor unit being located so as to surround the plurality of power modules from the outside in the radial direction, as seen from the axial direction.

Description

[Technical Field]

[0001] The present disclosure relates to a rotating electrical machine unit. This application claims priority based on Japanese Patent Application No. 2022-090051, filed on June 2, 2022, the contents of which are incorporated herein by reference. [Background technology]

[0002] Patent Document 1 discloses a rotating electric machine unit in which a rotating electric machine and a power conversion device are integrated together. The power conversion device has a capacitor unit and a plurality of power modules. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent No. 4708951 Summary of the Invention [Problem to be solved by the invention]

[0004] In order to increase the output of the rotating electrical machine unit, it is necessary to suppress the temperature rise of the capacitor unit.

[0005] The present disclosure has been made in consideration of the above-mentioned circumstances, and has an object to provide a rotating electrical machine unit that can suppress a rise in temperature of a capacitor unit and achieve high output. [Means for solving the problem]

[0006] The rotating electric machine unit according to the present disclosure comprises a rotating electric machine having a stator, a rotor that rotates around an axis relative to the stator, and a plurality of coils wound around the stator, and a power conversion device that is arranged alongside the rotating electric machine in an axial direction along the axis of the rotor, the power conversion device having a plurality of power modules that are electrically connected to the plurality of coils respectively, and a capacitor unit that is electrically connected to the plurality of power modules, and when viewed from the axial direction, the capacitor unit is arranged to surround the plurality of power modules from the radial outside. [Effects of the Invention]

[0007] According to the present disclosure, it is possible to provide a rotating electrical machine unit that can suppress a rise in the temperature of a capacitor unit and achieve high output. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a circuit diagram of a rotary electric machine unit according to a first embodiment. [Figure 2] 1 is a perspective view of a rotary electric machine unit according to a first embodiment. [Figure 3] 1 is a perspective view of a rotary electric machine unit according to a first embodiment, showing a state in which a case is removed. [Figure 4] FIG. 4 is a plan view of FIG. 3. [Figure 5] FIG. 5 is a cross-sectional view taken along line AA in FIG. [Figure 6] FIG. 5 is a cross-sectional view taken along line BB in FIG. [Figure 7] FIG. 2 is a perspective view of the rotating electrical machine unit, showing a state in which the case, terminal block, signal connector, and control board are removed. [Figure 8] FIG. 8 is a plan view of FIG. [Figure 9] FIG. 9 is a cross-sectional view taken along line CC in FIG. 8. [Figure 10] FIG. 9 is a cross-sectional view taken along line DD in FIG. 8. [Figure 11] FIG. 9 is a cross-sectional view taken along line EE in FIG. 8. [Figure 12] FIG. 1 is a perspective view of a capacitor module according to a first embodiment. [Figure 13] 1 is a perspective view of a capacitor module according to a first embodiment, showing a state in which a housing case is removed. [Figure 14] FIG. 2 is a perspective view of a positive electrode conductor according to the first embodiment. [Figure 15] FIG. 2 is a perspective view of a negative electrode conductor according to the first embodiment. [Figure 16] 1 is a perspective view of a power module, a bus bar, a current sensor, and a resin member according to a first embodiment. FIG. [Figure 17] FIG. 2 is a perspective view of a bus bar according to the first embodiment. [Figure 18] 1 is a perspective view of a rotating electric machine according to a first embodiment. [Figure 19] 1 is a perspective view of a rotating electric machine and a cooler according to a first embodiment. [Figure 20A] FIG. 2 is a perspective view of a plate according to the first embodiment. [Figure 20B] FIG. 2 is a perspective view of a plate according to the first embodiment. [Figure 21] FIG. 2 is a perspective view of a base and a refrigerant inlet according to the first embodiment. [Figure 22A] FIG. 2 is a perspective view of an inner cylindrical portion according to the first embodiment. [Figure 22B] FIG. 2 is a perspective view of an inner cylindrical portion according to the first embodiment. [Figure 23] FIG. 10 is a perspective view of a rotary electric machine unit according to a second embodiment. [Figure 24] FIG. 11 is a perspective view of a housing case for a capacitor module according to a third embodiment. [Figure 25] FIG. 11 is a cross-sectional view of a rotary electric machine unit according to a third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Embodiment 1 A rotating electrical machine unit 1 according to the first embodiment will be described below with reference to the drawings. FIG. 1 is a circuit diagram of the rotating electric machine unit 1. FIG. 2 is a perspective view of the rotating electric machine unit 1. As shown in FIGS. 2 and 19, the rotating electric machine unit 1 includes a rotating electric machine 2, a power converter 3, and a cooler 4 (first cooling section). The rotating electric machine 2, the power converter 3, and the cooler 4 are integrated together. This allows the rotating electric machine unit 1 to be made smaller. In this specification, the direction along the axis O (see FIG. 9) of the rotor 22 of the rotating electric machine 2 is referred to as the "axial direction." Further, the direction intersecting the axis O of the rotor 22 when viewed from the axial direction is referred to as the "radial direction," and the direction going around the axis O of the rotor 22 is referred to as the "circumferential direction."

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

[0011] The rotating electric machine 2 includes six coils 25U1, 25V1, 25W1, 25U2, 25V2, and 25W2 corresponding to the six phases (U1 phase, V1 phase, W1 phase, U2 phase, V2 phase, and W2 phase). Note that 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 the six phases (U1 phase, V1 phase, W1 phase, U2 phase, V2 phase, and W2 phase). Note that in this specification, the power modules 35U1, 35V1, 35W1, 35U2, 35V2, and 35W2 are also simply referred to as power modules 35.

[0013] DC power is input to the power converter 3 from a DC power source E such as a battery. The power converter 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 greatly in response to power fluctuations of the DC power supply E or power fluctuations on the power module 35 side. The capacitor unit 34 has a plurality of (two in this embodiment) 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 supply 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 supply E. Each power module 35 includes an upper arm switching element SW1 and a diode D1, and a lower arm switching element SW2 and a 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. A connection point between the switching elements SW1 and SW2 is electrically connected to the coil 25 of the corresponding phase. The diode D1 is connected in parallel in the reverse direction to the switching element SW1. The diode D2 is connected in parallel in the reverse direction to the switching element SW2.

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

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

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

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

[0020] The rotor 22 is provided inside the stator 21. The rotor 22 is rotatable about an axis O relative 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 accommodates the stator 21, the rotor 22, and the shaft 23. The housing 24 includes a cover 61, an inner cylindrical portion 62, an outer cylindrical 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 , the lid portion 61 is formed with coil through holes 61a through which the coil terminals 25a of the coils 25 are inserted. The six coil through holes 61a are arranged at equal intervals (60° intervals) in the circumferential direction. The lid portion 61 is formed with joint accommodating holes 61b into which the relay joints 47 described below are accommodated.

[0024] The inner cylinder portion 62 has a cylindrical shape. The inner cylinder portion 62 covers the stator 21 from the outside in the radial direction. The stator 21 is fixed to the inner cylinder portion 62 by, for example, shrink fitting or press fitting. The outer cylinder portion 63 has a cylindrical shape. The outer cylinder portion 63 covers the inner cylinder portion 62 from the outside in the radial direction. The outer cylinder portion 63 is fixed to the inner cylinder portion 62 by, for example, shrink fitting or press fitting. The inner cylindrical portion 62 and the outer cylindrical portion 63 form a second cooling portion 65 that cools the rotating electrical machine 2. Details of the second cooling portion 65 will be described later.

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

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

[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 cover 61. The resolver rotor 27b is attached to the upper end (non-output end) of the shaft 23.

[0028] The detection result of the resolver 27 is output to a control board 36 of the power conversion device 3, which will be described later, via a 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 so as to avoid the portion where the power module 35 is disposed. This makes it possible to prevent noise caused by the power module 35 from being transmitted to the resolver harness 27c, thereby improving the detection accuracy of the rotation angle of the shaft 23.

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

[0030] <Power conversion device> Next, the power converter 3 will be described with reference to FIGS. As shown in Figures 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 of (six in this embodiment) bus bars 37, a plurality of (six in this embodiment) current sensors 38, and a plurality of (six in this embodiment) resin members 39.

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

[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 connection terminal 32a is connected to the positive power supply terminal of the DC power supply E and to the positive conductors 54 of the two capacitor modules 51 of the capacitor unit 34, which will be described later. The negative connection terminal 32b is connected to the negative power supply terminal of the DC power supply E and to the negative 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] 3, the upper surface of the positive connection terminal 32a is exposed from the housing case 32c, and the positive power supply terminal of the DC power supply E is connected to this upper surface. Both side surfaces in the circumferential direction of the positive connection terminal 32a are exposed from the housing case 32c, and the positive conductors 54 of the two capacitor modules 51 are connected to these side surfaces, respectively. An upper surface of the negative connection terminal 32b is exposed from the housing case 32c, and is connected to the negative power supply terminal of the DC power supply E. Both circumferential side surfaces of the negative connection terminal 32b are exposed from the housing case 32c, and the negative conductors 55 of the two capacitor modules 51 are connected to these side surfaces, respectively.

[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 to exchange various signals between an external control device mounted on a vehicle or the like and the power conversion device 3. The signal connector 33 is a first external connection part that connects the power conversion device 3 and the external control device.

[0036] 4, when viewed from the axial direction, the side on which 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. 8, the capacitor unit 34 is disposed on the outer periphery of the power converter 3. When viewed in 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 (e.g., power modules 35U1, 35V1, 35W1), and the other is provided corresponding to the other half of the power modules 35 (e.g., 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 circumferential ends of the two capacitor modules 51.

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

[0040] Housing case 53 houses multiple capacitor elements 52, a portion of positive conductor 54, and a portion of negative conductor 55. In this state, resin is filled into housing case 53, thereby fixing the components housed in housing case 53. In housing case 53, capacitor elements 52 are arranged so that the positive electrode is located at the lower end and the negative electrode is located at the upper end.

[0041] A plurality of mounting portions 53a are formed on the bottom of the accommodating case 53 for mounting the capacitor module 51 to the lid portion 61. The mounting portions 53a are protrusions that protrude radially outward from the outer circumferential surface of the accommodating case 53. Bolt holes are formed in the mounting portions 53a, and the capacitor module 51 is mounted to the lid portion 61 by fastening bolts 53b (see FIG. 8) into the bolt holes.

[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. For example, oxygen-free copper is used as the material for the positive electrode conductor 54 and the negative electrode conductor 55. To reduce the cost of materials and improve their availability, tough pitch copper may also be used as the material for the positive electrode conductor 54 and the negative electrode conductor 55. 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 a positive electrode terminal 35b of the power module 35, which will be described later. The positive electrode conductor 54 has a plurality of (three in this embodiment) first positive electrode ends 54a, a second positive electrode end 54b, a plurality of third positive electrode ends 54c, a positive electrode side connection portion 54d, and a plurality of (three in this embodiment) positive electrode side cooled portions 54e.

[0044] The three first positive electrode ends 54a are provided corresponding to half (three) of the power modules 35. The first positive electrode ends 54a are connected to the positive electrode terminals 35b of the corresponding power modules 35. The three first positive electrode ends 54a are arranged at equal intervals (60° intervals) in the circumferential direction. The three first positive electrode ends 54a have the same shape. The first positive electrode ends 54a are drawn out from the upper part of the accommodating case 53. As shown in FIG. 8, the first positive electrode ends 54a are arranged so as to radially face the positive electrode terminals 35b of the corresponding power modules 35.

[0045] The second positive electrode end 54b is connected to the positive electrode side connection terminal 32a of the terminal block 32. The second positive electrode end 54b is drawn out from the upper part of the casing 53. As shown in Fig. 3, the second positive electrode end 54b is disposed so as 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 54b, and by fastening a bolt 54f into this bolt hole, the second positive electrode end 54b is fixed to the side surface of the positive electrode side connection terminal 32a.

[0046] The plurality of third positive electrode terminals 54c are provided corresponding to the plurality of capacitor elements 52, respectively. The third positive electrode terminals 54c are fixed to the lower ends of the capacitor elements 52 by, for example, soldering. As a result, the third positive electrode terminals 54c are connected to the positive electrodes provided at the lower ends of the capacitor elements 52. The third positive electrode terminals 54c are housed in the housing case 53.

[0047] The positive electrode side connecting 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 connecting portion 54d is accommodated in the accommodation case 53.

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

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

[0050] The positive electrode side cooled portion 54e is provided so as to extend downward from the first positive electrode end portion 54a. The positive electrode side cooled portion 54e is formed integrally with the first positive electrode end portion 54a. The positive electrode side cooled portion 54e may also be formed separately from the first positive electrode end portion 54a. 12, the positive electrode side cooled part 54e is arranged on the radially inner side of the capacitor module 51. The positive electrode side cooled part 54e is arranged on the outer side of the accommodating case 53. The positive electrode side cooled part 54e is thermally connected to the cooler 4.

[0051] The negative conductor 55 is connected to the negative connection terminal 32b of the terminal block 32 and a negative terminal 35c of the power module 35, which will be described later. The negative conductor 55 has a plurality of (three in this embodiment) first negative end portions 55a, a second negative end portion 55b, a plurality of third negative end portions 55c, a negative connection portion 55d, and a plurality of (three in this embodiment) negative cooled portions 55e.

[0052] The three first negative electrode end portions 55a are provided corresponding to half (three) of the power modules 35. The first negative electrode end portions 55a are connected to the negative electrode terminals 35c of the corresponding power modules 35. The three first negative electrode end portions 55a are arranged at equal intervals (60° intervals) in the circumferential direction. The three first negative electrode end portions 55a have the same shape. The first negative electrode end portions 55a are drawn out from the upper part of the accommodating case 53. As shown in FIG. 8, the first negative electrode end portions 55a are arranged so as to radially face the negative electrode terminals 35c of the corresponding power modules 35.

[0053] The second negative electrode end 55b is connected to the negative electrode side connection terminal 32b of the terminal block 32. The second negative electrode end 55b is drawn out from the upper part of the casing 53. As shown in Fig. 3, the second negative electrode end 55b is disposed 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 55b, and by fastening a bolt 55f into this bolt hole, the second negative electrode end 55b is fixed to the side surface of the negative electrode side connection terminal 32b.

[0054] The plurality of third negative electrode terminals 55c are provided corresponding to the plurality of capacitor elements 52, respectively. The third negative electrode terminals 55c are fixed to the upper ends of the capacitor elements 52 by, for example, soldering. As a result, the third negative electrode terminals 55c are connected to the negative electrodes provided at the upper ends of the capacitor elements 52. The third negative electrode terminals 55c are housed in the housing case 53.

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

[0056] The negative electrode side connecting portion 55d has a plurality of second straight portions 55d1, a plurality of second bent portions 55d2, and a second connecting end portion 55d3. The second straight portions 55d1 are formed, for example, by bending a plate-like member and are formed so as to extend generally in the circumferential direction as a whole. The second bent portions 55d2 connect the second straight portions 55d1 to each other. The second connecting end portion 55d3 is connected to the second straight portion 55d1 arranged on one side in the circumferential direction and is bent radially outward relative to the second straight portion 55d1.

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

[0058] The negative electrode side cooled portion 55e is provided so as to extend downward from the first negative electrode end portion 55a. The negative electrode side cooled portion 55e is formed integrally with the first negative electrode end portion 55a. The negative electrode side cooled portion 55e may also be formed separately from the first negative electrode end portion 55a. 12, the negative electrode side cooled part 55e is arranged on the radially inner side of the capacitor module 51. The negative electrode side cooled part 55e is arranged on the outer side of the accommodating case 53. The negative electrode side cooled part 55e is thermally connected to the cooler 4.

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

[0060] 16, each power module 35 has a main body 35a, a positive terminal 35b, a negative terminal 35c, an output terminal 35d, an upper arm signal terminal 35e, and a lower arm signal terminal 35f. The power module 35 is fixed to a plate 41 of the cooler 4, which will be described later.

[0061] The main body 35a has a generally rectangular shape when viewed in the axial direction. The main body 35a includes an upper arm switching element SW1 and a diode D1, and a lower arm switching element SW2 and a diode D2. The main body 35a has protrusions 35a1 at its corners for fixing the upper arm signal terminal 35e.

[0062] The positive terminal 35b, the negative terminal 35c, the output terminal 35d, the upper arm side signal terminal 35e, and the lower arm side signal terminal 35f are plate-shaped members. The positive electrode terminal 35b, the negative electrode terminal 35c, the output terminal 35d, the upper arm side signal terminal 35e, and the lower arm side signal terminal 35f are made of, for example, oxygen-free copper. To reduce material costs and improve material availability, tough pitch copper may be used as the material for the positive electrode terminal 35b, the negative electrode terminal 35c, the output terminal 35d, the upper arm side signal terminal 35e, and the lower arm side signal terminal 35f. The positive electrode terminal 35b, the negative electrode terminal 35c, the output terminal 35d, the upper arm side signal terminal 35e, and the lower arm side signal terminal 35f each have a thickness of, for example, 0.5 to 1.5 mm.

[0063] As shown in FIG. 8, the positive electrode terminal 35b is disposed opposite the first positive electrode end 54a. The positive electrode terminal 35b is directly connected to the first positive electrode end 54a. Note that "directly connected" means that the positive electrode terminal 35b and the first positive electrode end 54a are connected in contact with each other without using a wire or the like. The connection between the positive electrode terminal 35b and the first positive electrode end 54a can be achieved by, for example, resistance welding, ultrasonic welding, TIG welding, or laser welding. When viewed from the axial direction, the connection between the first positive electrode end 54a and the positive electrode terminal 35b is located between the housing case 53 and the main body 35a.

[0064] The negative electrode terminal 35c is disposed opposite the first negative electrode end 55a. The negative electrode terminal 35c is directly connected to the first negative electrode end 55a. Note that "directly connected" means that the negative electrode terminal 35c and the first negative electrode end 55a are connected in contact with each other without using a wire or the like. The connection between the negative electrode terminal 35c and the first negative electrode end 55a is made by, for example, resistance welding, ultrasonic welding, TIG welding, or laser welding. When viewed from the axial direction, the connection portion between the first negative electrode end 55a and the negative electrode terminal 35c is located between the housing case 53 and the main body 35a.

[0065] In this embodiment, the capacitor units 34 and the power modules 35 are arranged so that the length of the path from the positive conductor 54 of the capacitor unit 34, via the positive terminal 35b and the negative terminal 35c of the power module 35, to the negative conductor 55 of the capacitor unit 34 is approximately the same in all of the power modules 35. That is, the length of the connection path between the capacitor unit 34 and the power module 35 is approximately the same in all of the power modules 35. Here, "approximately the same path length" means that the difference in the path length between the power modules 35 with respect to the total length of the path from the positive conductor 54, via the positive terminal 35b and the negative terminal 35c, to the negative conductor 55 is within a range of ±5%. This makes it possible to equalize surge voltages generated in the power modules 35. This makes it possible to input a large amount of current to the power modules 35, thereby enabling the rotating electrical machine unit 1 to achieve high output.

[0066] In the present disclosure, it is sufficient that the lengths of the connection paths between the capacitor units 34 and the power modules 35 are approximately the same for at least two power modules 35. Even in this case, it is possible to equalize the surge voltages generated in these two power modules 35. This makes it possible to input a large amount of current to the power modules 35, thereby enabling the rotating electrical machine unit 1 to achieve high output.

[0067] Furthermore, the positive terminal 35b is directly connected to the first positive end 54a, and the negative terminal 35c is directly connected to the first negative end 55a. That is, the capacitor unit 34 and the power module 35 are connected via the shortest path. This reduces the inductance of the connection path between the capacitor unit 34 and the power module 35, and suppresses surge voltages occurring in the power module 35. This makes it possible to input a larger current into the power module 35, enabling the rotary electric machine unit 1 to achieve even higher output.

[0068] The output terminal 35 d is connected to the coil end 25 a of the coil 25 via a bus bar 37 . In all of the power modules 35, the output terminals 35d are arranged symmetrically with respect to an imaginary line passing through the axis O and the midpoint of the gap between the positive terminal 35b and the negative terminal 35c. That is, when viewed from the radial direction, the output terminals 35d are arranged so that the center position of the output terminals 35d coincides with the midpoint of the gap between the positive terminal 35b and the negative terminal 35c. This ensures that 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 is uniform in all of the power modules 35. This prevents bias in the current flowing through the power modules 35 from occurring among the multiple power modules 35.

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

[0070] The bus bar 37 will be described with reference to FIGS. Each bus bar 37 connects the power module 35 of the corresponding phase to the coil 25. As shown in Fig. 8, the bus bar 37 is disposed between the power modules 35 adjacent to each other in the circumferential direction.

[0071] 17, bus bar 37 is a plate-shaped member. For example, oxygen-free copper is used as the material of bus bar 37. Tough pitch copper may also be used as the material of bus bar 37 in order to reduce material costs and improve availability. The plate thickness of 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 end 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 disposed 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 in contact with each other without using a wire or the like. The first terminal 37a and the output terminal 35d are connected by, for example, resistance welding, ultrasonic welding, TIG welding, or laser welding. As shown in FIG. 8, when viewed in the axial direction, the connection portion between the first terminal 37a and the output terminal 35d is located radially inward of 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 disposed so as to face the coil terminal 25a. The second terminal 37b is directly connected to the coil terminal 25a. Note that "directly connected" means that the second terminal 37b and the coil terminal 25a are connected in contact with each other without using a wire or the like. The connection between the second terminal 37b and the coil terminal 25a is made by, for example, resistance welding, ultrasonic welding, TIG welding, or laser welding. As shown in FIG. 8, the connection portion between the second terminal 37b and the coil terminal 25a is located radially outward of the main body 35a when viewed in the axial direction.

[0075] A notch 37c is formed in the bus bar 37. The notch 37c is formed by cutting out 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 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 37c is formed so that the bus bar 37 and the signal terminal 35f on the lower arm side are spaced apart by 2.0 to 5.0 mm. This ensures insulation between the bus bar 37 and the signal terminal 35f on the lower arm side.

[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 a 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. This improves noise resistance and improves the accuracy with which the current sensor 38 can detect the current value of the bus bar 37.

[0078] 16, the bus bar 37 and the current sensor 38 are covered with a resin member 39. 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. For example, polyphenylene sulfide (PPS) is used as a material for the resin member 39. The resin member 39, together with the control board 36, is fixed to the plate 41 with bolts 41f3 (see FIG. 4).

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

[0080] 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 to the control board 36. 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 center 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 the vehicle or the like.

[0081] <Cooler> The cooler 4 will be described with reference to FIGS. The cooler 4 cools the power conversion device 3. As shown in Fig. 5, the cooler 4 is disposed radially inside the capacitor module 51 (capacitor unit 34). 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 has a plate 41, a base 42, a refrigerant inlet portion 43, a first heat dissipation member 44, and a second heat dissipation member 45 (condenser heat dissipation member).

[0082] 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. The power module 35 is attached to a first surface 41a of the plate 41. The power module 35 is fixed to the first surface 41a of the plate 41 by, for example, soldering. The power module 35 is thermally connected to the plate 41.

[0083] As shown in FIG. 20A, the first surface 41a of the plate 41 is provided with a first mounting hole 41h1, a second mounting hole 41h2, and a third mounting hole 41h3, each of which has a bottom.

[0084] A fixing post 41g (see FIG. 8) for fixing the control board 36 to the plate 41 is attached to the first mounting hole 41h1. 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 together with a bolt 41f1 (see FIG. 4), thereby fixing the control board 36 to the plate 41. Furthermore, as shown in FIG. 16, the fixing post 41g is inserted into a fixing through-hole 37d formed in the bus bar 37, thereby fixing the bus bar 37 to the plate 41.

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

[0086] A bolt 41f3 (see FIG. 4) for fixing the control board 36 and the resin member 39 to the plate 41 is attached to the third mounting hole 41h3. 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 together with the bolt 41f3, whereby the control board 36 and the resin member 39 are fixed to the plate 41.

[0087] 20B, heat dissipation fins 41c are provided on the second surface 41b of the plate 41. As shown in Fig. 11, the heat dissipation fins 41c are arranged at positions that overlap with the power modules 35 in the axial direction. The second surface 41b of the plate 41 is fixed to the base 42.

[0088] Harness through-holes 41d (insertion holes) through which the resolver harness 27c is inserted are formed in the plate 41. Coil grooves 41e in which the coil terminals 25a are disposed are formed in the outer peripheral surface of the plate 41. Six coil grooves 41e are disposed at equal intervals (at 60° intervals) in the circumferential direction.

[0089] As shown in Fig. 19, a first heat dissipation member 44 is provided on a first surface 41a of the plate 41. The first heat dissipation member 44 has a hexagonal shape. As shown in Fig. 11, the first heat dissipation 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 dissipation 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 generally polygonal shape having a first surface 42a, a second surface 42a, and a plurality of side surfaces. As shown in Fig. 11, the base 42 is surrounded from the outside in the radial direction by the capacitor module 51 (capacitor unit 34). The side surface of the base 42 faces the capacitor module 51 in the radial direction. The plate 41 is fixed to a first surface 42a of the base 42. A 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 center of the base 42. A coil groove 42c extending in the axial direction is formed on the side surface of the base 42. As shown in FIG. 19, the coil terminals 25a are arranged in the coil groove 42c. Six coil grooves 42c are formed at equal intervals (60° intervals) in the circumferential direction. A heat-conducting member may be filled between the coil groove 42c and the coil terminals 25a. In this case, the coil terminals 25a are thermally connected to the base 42 via the heat-conducting member. The coil 25 can be cooled by dissipating heat generated in the coil terminals 25a to the base 42 via the heat-conducting member. The coil terminals 25a can also be fixed to the coil groove 42c by the heat-conducting member.

[0092] A capacitor cooling section 42e that cools the capacitor module 51 is provided on a side surface of the base 42. As shown in Fig. 19, the capacitor cooling section 42e is provided with a second heat dissipation member 45. The second heat dissipation member 45 has a rectangular shape.

[0093] 6, the second heat dissipation member 45 is provided so as to radially 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. The positive electrode side cooled portion 54e and the negative electrode side cooled portion 55e are in contact with the second heat dissipation member 45 and are thermally connected to the capacitor cooling portion 42e via the second heat dissipation 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 protrude radially outward from the base 42. The refrigerant inlet portion 43 is formed integrally 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 electrical machine unit 1.

[0095] The cooler 4 is formed with a first cooling flow path through which a refrigerant flows. For example, water (cooling water) is used as the refrigerant. 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 a 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 with half of the six power modules 35 (specifically, power modules 35U1, 35V1, and 35W1) when viewed from 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 with the other half of the six power modules 35 (specifically, power modules 35U2, 35V2, and 35W2) when viewed from 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 join together. The outlet flow path P4 is connected to a second cooling flow path formed inside the second cooling section 65.

[0096] The base 42 is provided with a coolant supply port 42f, an annular groove 42g, and a coolant discharge port 42h.

[0097] The refrigerant supply port 42f is a hole that radially penetrates the peripheral wall of the base 42. One end of the refrigerant supply port 42f is connected to the refrigerant inlet portion 43. The other end of the refrigerant supply port 42f is connected to the 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 radially penetrates the peripheral wall of the base 42. The refrigerant discharge port 42h is arranged on the opposite side of 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 an intermediate joint 47. The intermediate joint 47 connects the refrigerant discharge port 42h to an opening 62c of the inner cylindrical portion 62, which will be described later. The refrigerant discharge port 42h and the intermediate joint 47 are used as an outlet flow path P4.

[0099] 8, the refrigerant inlet portion 43 is disposed in the front gap of two gaps between the circumferential ends of the capacitor module 51. The refrigerant discharge port 42h and the relay joint 47 are disposed in the rear gap of two gaps between the circumferential ends of the capacitor module 51. In other words, at least a portion of the inlet flow path P1 and at least a portion of the outlet flow path P4 are disposed between the circumferential ends of the capacitor module 51. The outlet flow path P4 is disposed on the radially opposite side of the axis O from the inlet flow path P1.

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

[0101] The annular groove 42g has a first groove 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 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 42g1 is provided below half of the six power modules 35 (specifically, power modules 35U1, 35V1, and 35W1). The second groove 42g2 is provided below the other half of the six power modules 35 (specifically, power modules 35U2, 35V2, and 35W2).

[0102] A first flow path P2 is formed by the first groove 42g1 and the second surface 41b of the plate 41. A second flow path P3 is formed by the second groove 42g2 and the second surface 41b of the plate 41. As shown in FIG. 11, the heat dissipation fin 41c is disposed inside the annular groove 42g (i.e., the first flow path P2 or the second flow path P3).

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

[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. Heat generated in the capacitor module 51 (capacitor element 52) ​​is transferred to the positive electrode side cooled portion 54e and the negative electrode side cooled portion 55e, and is heat exchanged with the refrigerant flowing through the first flow path P2 and the second flow path P3 via the condenser cooling portion 42e and the second heat dissipation member 45. This cools the capacitor module 51.

[0105] The bus bar 37 is thermally connected to the plate 41 via the first heat dissipation member 44. Heat generated in the bus bar 37 is 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. This cools the bus bar 37.

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

[0107] <Second cooling section> The second cooling section 65 will be described with reference to FIGS. 9, the inner cylindrical portion 62 and the outer cylindrical portion 63 form a second cooling portion 65. A second cooling flow path through which a refrigerant flows is formed in the second cooling portion 65. The second cooling flow path is formed between the outer peripheral surface of the inner cylindrical portion 62 and the inner peripheral surface of the outer cylindrical portion 63.

[0108] 22A and 22B are perspective views of the inner cylindrical portion 62. As shown in FIGS. 22A and 22B, the inner cylindrical portion 62 has a cylindrical main body portion 62a and a flange portion 62b that protrudes 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 an intermediate 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 is connected to 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 merge. The refrigerant is discharged to the outside from the discharge flow path P8.

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

[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. A communication flow path P5 is formed by the inner circumferential surface of the outer cylindrical portion 63 and the first groove portion 62d.

[0112] The second groove portion 62e is formed on the opposite circumferential side of the first groove portion 62d. The second groove portion 62e extends in the axial direction. The upper and lower ends of the second groove portion 62e are closed. The second groove portion 62e and the inner circumferential surface of the outer cylindrical 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 circumferentially from the first groove portion 62d to the second groove portion 62e. The multiple third groove portions 62f are formed at intervals in the axial direction. The third groove portions 62f and the inner circumferential surface of the outer cylindrical 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 from the first groove portion 62d to the second groove portion 62e on the other side in the circumferential direction. The multiple fourth groove portions 62g are formed at intervals in the axial direction. The fourth groove portion 62g and the inner circumferential surface of the outer cylindrical portion 63 form a fourth flow path P7.

[0115] 9, an opening 63a is formed at the lower end of the outer tubular portion 63, radially penetrating the peripheral wall of the outer tubular portion 63. The opening 63a is in communication with the second groove portion 62e. The opening 63a is connected to the second joint 48, which discharges the refrigerant to the outside. The second joint 48 is disposed on the front side of the rotating electrical machine unit 1.

[0116] The refrigerant discharged from the refrigerant discharge port 42h of the cooler 4 flows into the communication flow path P5 via the intermediate 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 branches into a third flow path P6 and a fourth flow path P7. The refrigerant flowing through the third flow path P6 cools one circumferential half of the rotating electric machine 2. The refrigerant flowing through the fourth flow path P7 cools the other circumferential half of the rotating electric machine 2. Since 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 electric machine 2 by the second cooling unit 65 is improved. The refrigerant from the third flow path P6 and the fourth flow path P7 then joins at the discharge flow path P8, flows downward through the discharge flow path P8, and is discharged to the outside via the opening 63a and the second joint 48.

[0117] As described above, the rotating electric machine unit 1 includes the rotating electric machine 2 and the power conversion device 3. The power conversion device 3 has a plurality of power modules 35 and a capacitor unit 34. When viewed in the axial direction, the capacitor unit 34 is disposed so as to surround the plurality of power modules 35 from the radially outer side. This makes it possible to suppress a rise in temperature of the capacitor unit 34 due to heat generated in the power module 35, compared to when the capacitor unit is arranged surrounded by a plurality of power modules. Also, the heat dissipation area of ​​the capacitor unit 34 can be increased, improving the heat dissipation performance of the capacitor unit 34. Therefore, a rise in temperature of the capacitor unit 34 can be suppressed, and the output of the rotating electrical machine unit 1 can be increased.

[0118] The capacitor unit 34 also has a positive conductor 54 and a negative conductor 55. The power module 35 has a positive terminal 35b and a negative terminal 35c. The length of a first path from the positive conductor 54 to the negative conductor 55, via the positive terminal 35b and the negative terminal 35c of a first power module 35 among the multiple power modules 35, is approximately the same as the length of a second path from the positive conductor 54 to the negative conductor 55, via the positive terminal 35b and the negative terminal 35c of a second power module 35 among the multiple power modules 35. Note that "the length of the first path is approximately the same as the length of the second path" means that the difference between the lengths of the first path and the second path is within ±5% of the total length of the first path. This makes it possible to equalize surge voltages generated in the first power module 35 and the second power module 35. Therefore, it becomes possible to input a large amount of current to the power module 35, and the rotating electrical machine unit 1 can have a high output.

[0119] In addition, in all of the power modules 35, the length of the path from the positive conductor 54 to the negative conductor 55 via the positive terminal 35b and the negative terminal 35c is approximately the same. This makes it possible to equalize the surge voltages generated in all of the power modules 35. This makes it possible for the power modules 35 to input a larger amount of current, thereby enabling the rotating electrical machine unit 1 to achieve even higher output.

[0120] The positive conductor 54 has a plurality of first positive ends 54a connected to the positive terminals 35b of the power modules 35, respectively. Each of the first positive ends 54a faces the corresponding positive terminal 35b in the radial direction. The negative conductor 55 has a plurality of first negative ends 55a connected to the negative terminals 35c of the power modules 35, respectively. Each of the first negative ends 55a faces the corresponding negative terminal 35c in the radial direction. This allows the first positive electrode end 54a to be easily connected to the positive electrode terminal 35b, and the first negative electrode end 55a to be easily connected to the negative electrode terminal 35c.

[0121] The positive conductor 54 has a second positive end 54b connected to the positive power supply terminal of the DC power supply E, a third positive end 54c connected to the positive electrode of the capacitor element 52, and a positive connection portion 54d electrically connecting the first positive end 54a, the second positive end 54b, and the third positive end 54c. When viewed in the axial direction, the positive connection portion 54d has a plurality of first straight portions 54d1 and a plurality of first bent portions 54d2 connecting the first straight portions 54d1 to each other. The negative conductor 55 has a second negative end 55b connected to the negative power supply terminal of the DC power supply E, a third negative end 55c connected to the negative electrode of the capacitor element 52, and a negative connection portion 55d electrically connecting the first negative end 55a, the second negative end 55b, and the third negative end 55c. When viewed in the axial direction, the negative electrode side connecting portion 55d has a plurality of second straight portions 55d1 and a plurality of second bent portions 55d2 that connect the plurality of second straight portions 55d1 together. By providing a plurality of first bent portions 54d2 in the positive electrode side connection portion 54d, the plurality of first straight portions 54d1 can be formed to extend generally in the circumferential direction as a whole. By providing a plurality of second bent portions 55d2 in the negative electrode side connection portion 55d, the plurality of second straight portions 55d1 can be formed to extend generally in the circumferential direction as a whole. This allows the capacitor unit 34 to be formed to extend in the circumferential direction when viewed in the axial direction, and the outer shape of the power conversion device 3 can be made circular when viewed in the axial direction, thereby enabling the rotating electrical machine unit 1 to be made smaller.

[0122] The positive conductor 54 is formed by joining a plurality of separate first positive end portions 54a, second positive end portions 54b, and third positive end portions 54c to a positive electrode side connecting portion 54d. The negative conductor 55 is formed by joining a plurality of separate first negative end portions 55a, second negative end portions 55b, and third negative end portions 55c to a negative electrode side connecting portion 55d. This improves the yield of the materials used for the positive electrode conductor 54 and the negative electrode conductor 55, thereby enabling the cost of the rotary electric machine unit 1 to be reduced.

[0123] The capacitor unit 34 also includes a plurality of capacitor modules 51 arranged in the circumferential direction. This allows for a reduction in manufacturing costs because it is possible to reduce the size of the molds and the like used to mold each component of the capacitor module 51. Furthermore, because the capacitor unit 34 can be transported as a plurality of capacitor modules 51, it is possible to reduce the space required for the tray that houses the capacitor units 34 during transportation, compared to when the capacitor unit 34 is formed from a single capacitor module, and this allows for a reduction in transportation costs.

[0124] The rotary electric machine 2 further includes a resolver 27, and the capacitor unit 34 is disposed so as to surround the resolver 27. This allows the capacitor unit 34 to be disposed in the space radially outside the resolver 27, thereby enabling the rotary electric machine unit 1 to be made smaller.

[0125] The power converter further includes a plurality of bus bars 37. The plurality of bus bars 37 are each formed with a notch 37c that cuts out an area facing a portion of the plurality of power modules 35. This forms a gap between the bus bar 37 and the power module 35, ensuring insulation between the bus bar 37 and the power module 35 and preventing a short circuit between the bus bar 37 and the power module 35. Therefore, compared to a case in which the notch 37c is not formed, the bus bar 37 and the power module 35 can be disposed closer to each other, and the power conversion device 3 can be made smaller.

[0126] The rotating electrical machine unit 1 also includes a cooler 4 having a first cooling flow path formed therein through which a coolant flows and which cools the power conversion device 3. The first cooling flow path includes an inlet flow path P1 to which the coolant is supplied, a first flow path P2 branching from the inlet flow path P1 and formed at a position overlapping with a first group of power modules 35 among the multiple power modules 35 when viewed in the axial direction, a second flow path P3 branching from the inlet flow path P1 and formed at a position overlapping with a second group of power modules 35 different from the first group among the multiple power modules 35 when viewed in the axial direction, and an outlet flow path P4 where the refrigerant from the first flow path P2 and the second flow path P3 join and where the refrigerant is discharged from the cooler 4. The cooler 4 can cool the power conversion device 3. The coolant is branched into a first flow path P2 and a second flow path P3 and flows through them. Therefore, compared to when multiple power modules 35 are arranged on a single cooling flow path, it is possible to prevent the temperature of the coolant from becoming uneven between the upstream and downstream sides of the cooling flow path. This allows the multiple power modules 35 to be cooled uniformly, improving the cooling performance of the rotating electrical machine unit 1. As a result, it is possible to improve the current density input to the power modules 35, enabling the rotating electrical machine unit 1 to have higher output.

[0127] Furthermore, in the center of the cooler 4, harness through holes 41d and 42b are formed, through which the resolver harness 27c of the resolver 27 is inserted. Since the resolver harness 27c can be disposed in the center of the cooler 4, the multiple power modules 35 can be disposed, for example, at equal intervals in the circumferential direction, improving the degree of freedom in arranging the power modules 35. Therefore, for example, the multiple power modules 35 can be disposed closer to each other, improving the packaging density of the components in the power conversion device 3 and enabling the rotating electrical machine unit 1 to be made smaller.

[0128] Moreover, the cooler 4 is disposed radially inside the capacitor unit 34. The capacitor unit 34 has a positive conductor 54 and a negative conductor 55. The positive conductor 54 has a positive-side cooled portion 54e disposed radially inside the capacitor unit 34. The negative conductor 55 has a negative-side cooled portion 55e disposed radially inside the capacitor unit 34. The cooler 4 is disposed radially outside the cooler 4, and has a capacitor cooling portion 42e thermally connected to the positive-side cooled portion 54e and the negative-side cooled portion 55e. The cooler 4 is disposed radially inside the capacitor unit 34. Therefore, the rotating electrical machine unit 1 can be made smaller in the axial direction than when the capacitor unit is disposed on the upper surface of the cooler, for example. Furthermore, the cooler 4 can cool the capacitor unit 34 from the radially inner side. This allows a larger area to be provided for cooling the capacitor unit 34, improving the cooling performance of the capacitor unit 34 and enabling the rotating electrical machine unit 1 to have a higher output. Furthermore, when the positive electrode conductor 54 and the negative electrode conductor 55 are made of copper, which has high thermal conductivity, the cooling performance of the capacitor unit 34 is further improved, and the rotating electrical machine unit 1 can have a higher output. Furthermore, since the capacitor unit 34 is cooled using the positive electrode side cooled part 54e and the negative electrode side cooled part 55e, which are not in the current flow path, the inductance of the connection path between the capacitor unit 34 and the power module 35 does not increase, and it is possible to suppress surge voltages occurring in the power module 35. Therefore, it becomes possible to input a large amount of current into the power module 35, and the output of the rotating electrical machine unit 1 can be further increased.

[0129] The rotating electrical machine unit 1 also includes a second cooling section 65 that is formed with a second cooling flow path through which a refrigerant flows and that 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 off 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 off from the communication flow path P5 and extends from the communication flow path P5 to the other side in the circumferential direction, and a discharge flow path P8 where the refrigerant from the third flow path P6 and the fourth flow path P7 join together and through which the refrigerant is discharged from the second cooling section 65. The first cooling flow path of the cooler 4 and the second cooling flow path of the second cooling section 65 are connected within the rotating electrical machine unit 1, thereby enabling the size of the rotating electrical machine unit 1 to be reduced. Furthermore, the refrigerant flowing through the third flow path P6 can cool one circumferential half of the rotating electrical machine 2, and the refrigerant flowing through the fourth flow path P7 can cool the other circumferential half of the rotating electrical machine 2, thereby improving the cooling efficiency of the rotating electrical machine 2 by the second cooling section 65.

[0130] The capacitor unit 34 includes a plurality of capacitor modules 51 that are arranged in the circumferential direction and have an arc shape when viewed in the axial direction. At least a portion of the inlet flow path P1 and at least a portion of the outlet flow path P4 are arranged between the circumferential ends of the plurality of capacitor modules 51. The outlet flow path P4 is arranged on the radially opposite side of the inlet flow path P1, with the axis O of the rotor 22 in between. At least a portion of the inlet flow path P1 and at least a portion of the outlet flow path P4 are disposed between circumferential ends of the plurality of capacitor modules 51, thereby enabling miniaturization of the rotary electric machine unit 1. Furthermore, 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, thereby reducing pressure loss in the inlet flow path P1 and the outlet flow path P4 and improving the cooling performance of the cooler 4.

[0131] The power conversion device 3 also includes a signal connector 33 and a terminal block 32. The signal connector 33 is disposed on the front side of the rotating electrical machine unit 1, and the terminal block 32 is disposed on the rear side of the rotating electrical machine unit 1. This prevents noise generated from the terminal block 32 from propagating to the signal connector 33, allowing various signals to be transmitted and received accurately between the signal connector 33 and an external control device.

[0132] In addition, the positive conductor 54 and the positive terminal 35b are connected radially between the capacitor unit 34 and the power module 35, and the negative conductor 55 and the negative terminal 35c are connected radially between the capacitor unit 34 and the power module 35. This allows the capacitor unit 34 arranged on the radially outer side to be connected to the power module 35 arranged on the radially inner side via the shortest connection path, thereby reducing the inductance of the connection path and suppressing surge voltages generated in the power module 35. This makes it possible to input a large amount of current into the power module 35, enabling the rotating electrical machine unit 1 to achieve even higher output.

[0133] The power conversion device 3 further includes a control board 36 that controls the multiple power modules 35, and multiple current sensors 38 that detect currents flowing through the multiple bus bars 37. Each of the multiple current sensors 38 is directly connected to the control board 36. This shortens the connection path between the signal terminal 38a of the current sensor 38 and the control board 36, thereby improving noise resistance. Also, since the current sensor 38 and the control board 36 are connected without using a harness or the like, the cost and weight of the rotating electrical machine unit 1 can be reduced.

[0134] Each of the bus bars 37 has a first terminal 37a connected to a corresponding one of the power modules 35, and a second terminal 37b connected to a corresponding one of the coils 25. The first terminal 37a is located radially outward of the main body 35a of the corresponding power module 35. This allows the power modules 35 to be positioned radially inward, i.e., adjacent power modules 35 to be positioned closer to each other in the circumferential direction, compared to when the first terminal of the bus bar is positioned between adjacent power modules, thereby making it possible to reduce the size of the rotating electric unit 1.

[0135] Furthermore, the plurality of bus bars 37 and the plurality of power modules 35 are arranged alternately in the circumferential direction. This allows the packaging density of the power converters 3 to be improved, and the rotating electrical machine unit 1 to be made smaller.

[0136] Embodiment 2 Next, a rotating electric machine unit 1 according to embodiment 2 will be described. The rotating electric machine unit according to this embodiment has the same basic configuration as the rotating electric machine unit 1 of embodiment 1, so differences will be mainly described. Fig. 23 is a perspective view of the rotating electric machine unit 1, showing a state in which the case 31, terminal block 32, and control board 36 have been removed.

[0137] 23, in this embodiment, the positive terminal 35b and the negative terminal 35c extend in a direction perpendicular to the axial direction (in this embodiment, approximately the radial direction) in the power module 35. In the capacitor module 51, the first positive end 54a of the positive conductor 54 and the first negative end 55a of the negative conductor 55 extend in a direction perpendicular to the axial direction (in this embodiment, approximately the radial direction).

[0138] The positive terminal 35b is disposed so as to overlap the first positive end 54a in the axial direction. The positive terminal 35b abuts against the first positive end 54a from above. That is, the lower surface of the positive terminal 35b (i.e., the surface of the positive terminal 35b facing the rotating electric machine 2) and the upper surface of the first positive end 54a (i.e., the surface of the first positive end 54a opposite to the rotating electric machine 2) face each other in the axial direction and contact each other. In addition, the plate thickness of the positive terminal 35b (i.e., the axial size of the positive terminal 35b) is smaller than the plate thickness of the first positive end 54a (i.e., the axial size of the first positive end 54a).

[0139] The positive terminal 35b is directly connected to the first positive end 54a. "Directly connected" means that the positive terminal 35b and the first positive end 54a are connected in contact with each other without using a wire or the like. The positive terminal 35b and the first positive end 54a are connected by laser welding, for example. In this case, the laser welding is performed from the positive terminal 35b side. The laser welded portion between the positive terminal 35b and the first positive end 54a is the first connection C1 between the first positive end 54a and the positive terminal 35b. When viewed from the axial direction, the first connection C1 is located between the housing 53 of the capacitor unit 34 and the main body 35a of the power module 35.

[0140] The negative electrode terminal 35c is disposed so as to overlap the first negative electrode end 55a in the axial direction. The negative electrode terminal 35c abuts against the first negative electrode end 55a from above. That is, the lower surface of the negative electrode terminal 35c (i.e., the surface of the negative electrode terminal 35c facing the rotating electric machine 2) and the upper surface of the first negative electrode end 55a (i.e., the surface of the first negative electrode end 55a opposite to the rotating electric machine 2) face each other in the axial direction and contact each other. In addition, the plate thickness of the negative electrode terminal 35c (i.e., the axial size of the negative electrode terminal 35c) is smaller than the plate thickness of the first negative electrode end 55a (i.e., the axial size of the first negative electrode end 55a).

[0141] The negative electrode terminal 35c is directly connected to the first negative electrode end 55a. "Directly connected" means that the negative electrode terminal 35c and the first negative electrode end 55a are connected in contact with each other without using a wire or the like. The negative electrode terminal 35c and the first negative electrode end 55a are connected by, for example, laser welding. In this case, the laser welding is performed from the negative electrode terminal 35c side. The laser welded portion between the negative electrode terminal 35c and the first negative electrode end 55a is the second connection portion C2 between the first negative electrode end 55a and the negative electrode terminal 35c. When viewed from the axial direction, the second connection portion C2 is located between the housing case 53 of the capacitor unit 34 and the main body portion 35a of the power module 35.

[0142] As described above, in this embodiment, the surface of either the positive terminal 35b or the positive conductor 54 facing the rotating electric machine 2 and the surface of the other of the positive terminal 35b or the positive conductor 54 facing the opposite side to the rotating electric machine 2 are in contact with each other. Also, the surface of either the negative terminal 35c or the negative conductor 55 facing the rotating electric machine 2 and the surface of the other of the negative terminal 35c or the negative conductor 55 facing the opposite side to the rotating electric machine 2 are in contact with each other. This allows for a reduction in the amount of material used for the positive conductor 54, the negative conductor 55, the positive terminal 35b, and the negative terminal 35c, thereby reducing the cost of the rotating electric machine unit 1 and making the rotating electric machine unit 1 lighter.

[0143] If the thickness of the first positive electrode end 54a is smaller than the thickness of the positive electrode terminal 35b, the first positive electrode end 54a may be disposed above the positive electrode terminal 35b, and laser welding may be performed from the first positive electrode end 54a side. In this case, the upper surface of the positive electrode terminal 35b (i.e., the surface of the positive electrode terminal 35b opposite the rotating electric machine 2 side) and the lower surface of the first positive electrode end 54a (i.e., the surface of the first positive electrode end 54a facing the rotating electric machine 2) face each other in the axial direction and come into contact with each other. If the thickness of the first negative electrode end 55a is smaller than the thickness of the negative electrode terminal 35c, the first negative electrode end 55a may be disposed above the negative electrode terminal 35c, and laser welding may be performed from the first negative electrode end 55a side. In this case, the upper surface of the negative electrode terminal 35c (i.e., the surface of the negative electrode terminal 35c opposite the rotating electric machine 2 side) and the lower surface of the first negative electrode end 55a (i.e., the surface of the first negative electrode end 55a facing the rotating electric machine 2 side) face each other in the axial direction and come into contact with each other. That is, laser welding is performed from the thinner plate side of the first positive electrode end 54a and the positive electrode terminal 35b, and laser welding is performed from the thinner plate side of the first negative electrode end 55a and the negative electrode terminal 35c. This reduces the penetration depth of the weld required for laser welding, allowing for a reduction in the output of the laser welder and a reduction in equipment costs. Furthermore, the time required for laser welding can be shortened, improving productivity.

[0144] Embodiment 3 Next, a rotating electric machine unit 1 according to a third embodiment will be described. The rotating electric machine unit according to this embodiment has the same basic configuration as the rotating electric machine unit 1 of the first embodiment, so differences will be mainly described. Fig. 24 is a perspective view of a housing case 53A of a capacitor module 51 according to this embodiment. Fig. 25 is a cross-sectional view of the rotating electric machine unit 1 according to this embodiment, taken along line EE in Fig. 8.

[0145] As shown in FIG. 24 , the housing case 53A has a main body 531 and a plurality of pressing members 532 fixed to the main body 531. The pressing members 532 are provided on a surface of the main body 531 facing radially inward. The pressing members 532 are elastic. The upper end of the pressing members 532 is fixed to the surface of the main body 531 facing radially inward. The lower end of the pressing members 532 is provided with a protrusion that protrudes radially inward. The main body 531 and the pressing members 532 are made of, for example, resin. The main body 531 and the pressing members 532 are integrally molded. The pressing members 532 may be attached to the surface of the main body 531 facing radially inward using an adhesive.

[0146] As shown in FIG. 25 , the positive-side cooled portion 54e and the negative-side cooled portion 55e are disposed radially inside the pressing member 532. More specifically, the main body 531, the pressing member 532, the positive-side cooled portion 54e or the negative-side cooled portion 55e, the second heat dissipation member 45, and the base 42 (capacitor cooling portion 42e) are disposed in this order from the outside to the inside in the radial direction. The lower end of the pressing member 532 abuts against the positive-side cooled portion 54e and the negative-side cooled portion 55e from the outside in the radial direction. At this time, the lower end of the pressing member 532 is elastically deformed radially outward. The elastic force of the pressing member 532 presses the positive-side cooled portion 54e and the negative-side cooled portion 55e against the second heat dissipation member 45.

[0147] As described above, in this embodiment, the capacitor unit 34 has the pressing members 532 that press the positive electrode side cooled portion 54e and the negative electrode side cooled portion 55e against the second heat dissipation member 45. This improves the adhesion between the positive electrode side cooled portion 54e and the negative electrode side cooled portion 55e and the second heat dissipation member 45, thereby improving the cooling performance of the capacitor unit 34 and enabling the rotating electrical machine unit 1 to have a higher output.

[0148] The technical scope of the present disclosure is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present disclosure.

[0149] For example, the rotating electrical machine unit 1 may be a rotating electrical machine unit of a polyphase drive type with six or more phases. The capacitor unit 34 may be configured with only one capacitor module 51. The capacitor unit 34 may have three or more capacitor modules 51.

[0150] Various aspects of the present disclosure are summarized below as appendices.

[0151] (Appendix 1) a rotating electric machine including a stator, a rotor that rotates about an axis relative to the stator, and a plurality of coils wound around the stator; a power conversion device that is arranged alongside the rotating electric machine in an axial direction along an axis of the rotor, 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, When viewed from the axial direction, the capacitor unit is disposed so as to surround the plurality of power modules from the radially outer side.

[0152] (Appendix 2) The capacitor unit has a positive conductor and a negative conductor, each of the plurality of power modules has a positive terminal connected to the positive conductor and a negative terminal connected to the negative conductor; 2. The rotating electric unit according to claim 1, wherein a length of a first path from the positive conductor to the negative conductor, via the positive terminal and the negative terminal of a first power module among the plurality of power modules, is approximately the same as a length of a second path from the positive conductor to the negative conductor, via the positive terminal and the negative terminal of a second power module among the plurality of power modules.

[0153] (Appendix 3) 3. The rotating electric unit according to claim 2, wherein in all of the plurality of power modules, the length of the path from the positive conductor to the negative conductor via the positive terminal and the negative terminal is approximately the same.

[0154] (Appendix 4) the capacitor unit includes a capacitor element, a positive electrode conductor electrically connected to a positive electrode of the capacitor element, and a negative electrode conductor electrically connected to a negative electrode of the capacitor element; each of the plurality of power modules has a positive terminal electrically connected to the positive conductor and a negative terminal electrically connected to the negative conductor; the positive conductor has a plurality of first positive electrode ends connected to the positive electrode terminals of the plurality of power modules, respectively, and each of the plurality of first positive electrode ends faces a corresponding positive electrode terminal in a radial direction; The rotating electric unit according to any one of appendices 1 to 3, wherein the negative conductor has a plurality of first negative electrode ends that are respectively connected to the negative electrode terminals of the plurality of power modules, and each of the plurality of first negative electrode ends is radially opposed to the corresponding negative electrode terminal.

[0155] (Appendix 5) The positive electrode conductor is a second positive end portion electrically connected to a positive power terminal of an external power source; a third positive electrode end connected to the positive electrode of the capacitor element; a positive electrode side connection portion that electrically connects the plurality of first positive electrode ends, the second positive electrode end, and the third positive electrode end; and When viewed from the axial direction, the positive electrode side connection portion has a plurality of first straight portions and a plurality of first bent portions connecting the plurality of first straight portions to each other, The negative electrode conductor is a second negative electrode end portion electrically connected to a negative electrode power terminal of an external power source; a third negative electrode end portion connected to the negative electrode of the capacitor element; a negative electrode side connection portion that electrically connects the plurality of first negative electrode ends, the second negative electrode end portion, and the third negative electrode end portion; and A rotating electric unit as described in Appendix 4, wherein, when viewed from the axial direction, the negative power supply terminal has a plurality of second straight portions and a plurality of second bent portions connecting the plurality of second straight portions to each other.

[0156] (Appendix 6) the positive electrode conductor is formed by joining the plurality of first positive electrode ends, the second positive electrode end, and the third positive electrode end, which are separate bodies, to the positive electrode-side connecting portion, A rotating electric unit as described in Appendix 5, wherein the negative conductor is formed by joining the plurality of separate first negative electrode ends, the second negative electrode end, and the third negative electrode end to the negative electrode side connection portion.

[0157] (Appendix 7) 7. The rotating electrical machine unit according to any one of claims 1 to 6, wherein the capacitor unit includes a plurality of capacitor modules arranged in a circumferential direction.

[0158] (Appendix 8) the rotating electric machine further includes a resolver disposed between the stator and the power module, the resolver detecting a rotation angle of a shaft disposed at a center of the rotor, 8. The rotating electrical machine unit according to claim 1, wherein the capacitor unit is disposed so as to surround the resolver.

[0159] (Appendix 9) a first cooling section having a first cooling flow path through which a coolant flows and configured to cool the power conversion device; Furthermore, The first cooling channel is an inlet flow path to which the refrigerant is supplied; a first flow path branching from the inlet flow path and 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 branching from the inlet flow path and formed at a position overlapping a second group of power modules different from the first group among the plurality of power modules when viewed from the axial direction; The rotating electrical unit according to any one of appendices 1 to 8, further comprising an outlet flow path where the coolant from the first flow path and the second flow path join together and through which the coolant is discharged from the first cooling portion.

[0160] (Appendix 10) the rotating electric machine further includes a resolver disposed between the stator and the power module, the resolver detecting a rotation angle of a shaft disposed at a center of the rotor, 10. The rotating electrical machine unit according to claim 9, wherein a through-hole through which a signal line of the resolver is inserted is formed in a central portion of the first cooling portion.

[0161] (Appendix 11) the first cooling unit is disposed radially inside the capacitor unit, The capacitor unit has a positive conductor and a negative conductor, the positive conductor has a positive-side cooled portion that is arranged radially inside the capacitor unit, the negative conductor has a negative-side cooled portion disposed radially inside the capacitor unit, The rotating electric unit according to claim 9 or 10, wherein the first cooling section has a capacitor cooling section that is arranged radially outside the first cooling section and thermally connected to the positive electrode side cooled section and the negative electrode side cooled section.

[0162] (Appendix 12) a second cooling section having a second cooling flow path through which a coolant flows and configured to cool the rotating electrical machine; Furthermore, The second cooling channel is a communication flow path communicating with the outlet flow path; a third flow path branching from the communication flow path and extending from the communication flow path to one side in the circumferential direction; a fourth flow path branching from the communication flow path and extending from the communication flow path to the other side in the circumferential direction; 12. The rotating electrical unit according to any one of claims 9 to 11, further comprising: a discharge flow path where the coolant from the third flow path and the fourth flow path join together and through which the coolant is discharged from the second cooling section.

[0163] (Appendix 13) the capacitor unit includes a plurality of capacitor modules that are arranged in a circumferential direction and have an arc shape when viewed from the axial direction, at least a portion of the inlet flow path and at least a portion of the outlet flow path are disposed between ends of the plurality of capacitor modules in the circumferential direction; 13. The rotary electric machine unit according to any one of claims 9 to 12, wherein the outlet passage is disposed on the radially opposite side of the inlet passage across the axis of the rotor.

[0164] (Appendix 14) the power conversion device includes a first external connection unit that connects the power conversion device to an external control device, and a second external connection unit that connects the power conversion device to an external power supply; When viewed from the axial direction, the side on which the first external connection portion is arranged with respect to the axis of the rotor is referred to as a front side, and the opposite side is referred to as a rear side. A rotating electric machine unit according to any one of appendices 1 to 13, wherein the first external connection part is arranged on the front side of the rotating electric machine unit, and the second external connection part is arranged on the rear side of the rotating electric machine unit.

[0165] (Appendix 15) The capacitor unit has a positive conductor and a negative conductor, Each of the plurality of power modules has a positive terminal and a negative terminal, The rotating electric unit according to any one of appendixes 1 to 14, wherein the positive conductor and the positive terminal are connected radially between the capacitor unit and the power module, and the negative conductor and the negative terminal are connected radially between the capacitor unit and the power module.

[0166] (Appendix 16) 16. The rotating electrical machine unit according to any one of claims 1 to 15, wherein the power conversion device further includes a plurality of bus bars connecting the plurality of power modules to the plurality of coils, respectively.

[0167] (Appendix 17) The rotating electric unit according to claim 16, wherein the bus bars have cutouts formed in areas facing parts of the power modules.

[0168] (Appendix 18) the power conversion device further includes a control board that controls the plurality of power modules; and a plurality of current sensors that detect currents flowing through the plurality of bus bars, 18. The rotating electrical machine unit according to claim 16, wherein each of the plurality of current sensors is directly connected to the control board.

[0169] (Appendix 19) each of the plurality of bus bars has a first terminal connected to a corresponding one of the plurality of power modules and a second terminal connected to a corresponding one of the plurality of coils; 19. The rotating electrical unit according to any one of claims 16 to 18, wherein the first terminal is located radially inward of the main body of the corresponding power module.

[0170] (Appendix 20) 20. The rotary electric machine unit according to any one of claims 16 to 19, wherein the plurality of bus bars and the plurality of power modules are arranged alternately in the circumferential direction.

[0171] (Appendix 21) a surface of one of the positive terminal and the positive conductor facing the rotating electric machine and a surface of the other of the positive terminal and the positive conductor facing away from the rotating electric machine are in contact with each other, A rotating electric machine unit as described in Appendix 2, wherein a surface of either the negative terminal or the negative conductor facing the rotating electric machine and a surface of the other of the negative terminal or the negative conductor facing away from the rotating electric machine face each other and are in contact with each other.

[0172] (Appendix 22) a capacitor heat dissipation member is provided between the positive electrode side cooled portion and the negative electrode side cooled portion and the capacitor cooling portion, 14. The rotating electrical machine unit according to any one of claims 11 to 13, wherein 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 dissipation member. [Explanation of symbols]

[0173] 1 Rotating electric unit 2 Rotating electric machines 3 Power conversion device 4 Cooler (1st cooling section) 21 Stator 22 Rotor 23 Shaft 25 coils 27 Resolver 32 Terminal block (second external connection part) 33 Signal connector (first external connection part) 34 Capacitor Unit 35 Power Module 35b Positive terminal 35c negative terminal 37 Busbar 42e Condenser cooling section 45 Second heat dissipation member (condenser heat dissipation member) 51 Capacitor module 52 Capacitor element 54 Positive conductor 54a 1st positive end 54b 2nd positive end 54c 3rd positive end 54d Positive electrode connection 54d1 First straight section 54d2 First bending section 54e Positive side cooled part 55 Negative conductor 55a 1st negative end 55b 2nd negative end 55c 3rd negative end 55d Negative electrode connection part 55d1 Second straight section 55d2 Second bending section 55e Negative side cooled part 65 2nd cooling section 532 Pressing member O axis center P1 inlet channel P2 First flow path P3 Second flow path P4 outlet flow path P5 Connecting flow path P6 3rd flow path P7 4th flow path P8 Discharge flow path

Claims

1. a rotating electric machine including a stator, a rotor that rotates about an axis relative to the stator, and a plurality of coils wound around the stator; a power conversion device that is arranged alongside the rotating electric machine in an axial direction along an axis of the rotor, 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, When viewed from the axial direction, the capacitor unit extends in a circumferential direction and is disposed so as to surround the plurality of power modules from the outside in the radial direction, The capacitor unit has a positive conductor and a negative conductor, each of the plurality of power modules has a positive terminal connected to the positive conductor and a negative terminal connected to the negative conductor; a length of a first path from the positive conductor to the negative conductor, via the positive terminal and the negative terminal of a first power module among the plurality of power modules, is approximately the same as a length of a second path from the positive conductor to the negative conductor, via the positive terminal and the negative terminal of a second power module among the plurality of power modules.

2. 2. The rotating electrical unit according to claim 1, wherein the lengths of the paths from the positive conductors to the negative conductors via the positive terminals and the negative terminals are substantially the same in all of the plurality of power modules.

3. a rotating electric machine including a stator, a rotor that rotates about an axis relative to the stator, and a plurality of coils wound around the stator; a power conversion device that is arranged alongside the rotating electric machine in an axial direction along an axis of the rotor, 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, When viewed from the axial direction, the capacitor unit extends in a circumferential direction and is disposed so as to surround the plurality of power modules from the outside in the radial direction, the capacitor unit includes a capacitor element, a positive electrode conductor electrically connected to a positive electrode of the capacitor element, and a negative electrode conductor electrically connected to a negative electrode of the capacitor element; each of the plurality of power modules has a positive terminal electrically connected to the positive conductor and a negative terminal electrically connected to the negative conductor; the positive conductor has a plurality of first positive electrode ends connected to the positive electrode terminals of the plurality of power modules, respectively, and the plurality of first positive electrode ends are each radially opposed to the corresponding positive electrode terminal; the negative conductor has a plurality of first negative electrode ends that are respectively connected to the negative electrode terminals of the plurality of power modules, and each of the plurality of first negative electrode ends is radially opposed to a corresponding negative electrode terminal.

4. The positive electrode conductor is a second positive end electrically connected to a positive power terminal of an external power source; a third positive electrode end connected to the positive electrode of the capacitor element; a positive electrode side connection portion that electrically connects the plurality of first positive electrode ends, the second positive electrode end, and the third positive electrode end; and When viewed from the axial direction, the positive electrode side connection portion has a plurality of first straight portions and a plurality of first bent portions connecting the plurality of first straight portions to each other, The negative electrode conductor is a second negative electrode end portion electrically connected to a negative electrode power supply terminal of an external power supply; a third negative electrode end portion connected to the negative electrode of the capacitor element; a negative electrode side connection portion that electrically connects the plurality of first negative electrode terminals, the second negative electrode terminal, and the third negative electrode terminal; and 4. The rotating electric unit according to claim 3, wherein when viewed from the axial direction, the negative electrode side connection portion has a plurality of second straight portions and a plurality of second bent portions connecting the plurality of second straight portions to each other.

5. the positive electrode conductor is formed by joining the plurality of first positive electrode ends, the second positive electrode end, and the third positive electrode end, which are separate bodies, to the positive electrode-side connecting portion, 5. The rotating electric unit according to claim 4, wherein the negative conductor is formed by joining the plurality of separate first negative electrode ends, the second negative electrode end, and the third negative electrode end to the negative electrode side connection portion.

6. a rotating electric machine including a stator, a rotor that rotates about an axis relative to the stator, and a plurality of coils wound around the stator; a power conversion device that is arranged alongside the rotating electric machine in an axial direction along an axis of the rotor, 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, When viewed from the axial direction, the capacitor unit extends in a circumferential direction and is disposed so as to surround the plurality of power modules from the outside in the radial direction, The capacitor unit is a rotating electrical unit including a plurality of capacitor modules arranged in a circumferential direction.

7. a rotating electric machine including a stator, a rotor that rotates about an axis relative to the stator, and a plurality of coils wound around the stator; a power conversion device that is arranged alongside the rotating electric machine in an axial direction along an axis of the rotor, 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, When viewed from the axial direction, the capacitor unit extends in a circumferential direction and is disposed so as to surround the plurality of power modules from the outside in the radial direction, the rotating electric machine further includes a resolver disposed between the stator and the power module, the resolver detecting a rotation angle of a shaft disposed at a center of the rotor, The capacitor unit is disposed so as to surround the resolver.

8. a rotating electric machine including a stator, a rotor that rotates about an axis relative to the stator, and a plurality of coils wound around the stator; a power conversion device that is arranged alongside the rotating electric machine in an axial direction along an axis of the rotor, 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, When viewed from the axial direction, the capacitor unit extends in a circumferential direction and is disposed so as to surround the plurality of power modules from the outside in the radial direction, a first cooling section having a first cooling flow path through which a coolant flows and configured to cool the power conversion device; Furthermore, The first cooling channel is an inlet flow path to which the refrigerant is supplied; a first flow path branching from the inlet flow path and 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 branching from the inlet flow path and formed at a position overlapping a second group of power modules different from the first group among the plurality of power modules when viewed from the axial direction; the rotating electrical unit has an outlet flow path where the coolant from the first flow path and the second flow path join together and through which the coolant is discharged from the first cooling portion.

9. the rotating electric machine further includes a resolver disposed between the stator and the power module, the resolver detecting a rotation angle of a shaft disposed at a center of the rotor, The rotating electrical unit according to claim 8 , wherein a through-hole through which a signal line of the resolver is inserted is formed in a central portion of the first cooling portion.

10. the first cooling unit is disposed radially inside the capacitor unit, The capacitor unit has a positive conductor and a negative conductor, the positive conductor has a positive-side cooled portion that is arranged radially inside the capacitor unit, the negative conductor has a negative-side cooled portion disposed radially inside the capacitor unit, 9. The rotating electric unit according to claim 8, wherein the first cooling section has a capacitor cooling section that is arranged radially outside the first cooling section and is thermally connected to the positive electrode side cooled section and the negative electrode side cooled section.

11. a second cooling section having a second cooling flow path through which a coolant flows and configured to cool the rotating electrical machine; Furthermore, The second cooling channel is a communication flow path communicating with the outlet flow path; a third flow path branching from the communication flow path and extending from the communication flow path to one side in the circumferential direction; a fourth flow path branching from the communication flow path and extending from the communication flow path to the other side in the circumferential direction; The rotating electrical unit according to claim 8 , further comprising: a discharge flow path where the coolant from the third flow path and the fourth flow path join together and through which the coolant is discharged from the second cooling portion.

12. the capacitor unit includes a plurality of capacitor modules that are arranged in a circumferential direction and have an arc shape when viewed from the axial direction, at least a portion of the inlet flow path and at least a portion of the outlet flow path are disposed between ends of the plurality of capacitor modules in the circumferential direction; The rotating electrical unit according to claim 8 , wherein the outlet flow passage is disposed on a radially opposite side of the inlet flow passage across an axial center of the rotor.

13. a rotating electric machine including a stator, a rotor that rotates about an axis relative to the stator, and a plurality of coils wound around the stator; a power conversion device arranged alongside the rotating electric machine in an axial direction along an axis of the rotor, 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, When viewed from the axial direction, the capacitor unit extends in a circumferential direction and is disposed so as to surround the plurality of power modules from the outside in the radial direction, the power conversion device includes a first external connection unit that connects the power conversion device to an external control device, and a second external connection unit that connects the power conversion device to an external power supply, When viewed from the axial direction, the side on which the first external connection portion is arranged with respect to the axis of the rotor is referred to as a front side, and the opposite side is referred to as a rear side. The rotating electric machine unit, wherein the first external connection portion is disposed on a front side of the rotating electric machine unit, and the second external connection portion is disposed on a rear side of the rotating electric machine unit.

14. a rotating electric machine including a stator, a rotor that rotates about an axis relative to the stator, and a plurality of coils wound around the stator; a power conversion device that is arranged alongside the rotating electric machine in an axial direction along an axis of the rotor, 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, When viewed from the axial direction, the capacitor unit extends in a circumferential direction and is disposed so as to surround the plurality of power modules from the outside in the radial direction, The capacitor unit has a positive conductor and a negative conductor, Each of the plurality of power modules has a positive terminal and a negative terminal, the positive conductor and the positive terminal are connected radially between the capacitor unit and the power module, and the negative conductor and the negative terminal are connected radially between the capacitor unit and the power module.

15. a rotating electric machine including a stator, a rotor that rotates about an axis relative to the stator, and a plurality of coils wound around the stator; a power conversion device that is arranged alongside the rotating electric machine in an axial direction along an axis of the rotor, 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, When viewed from the axial direction, the capacitor unit extends in a circumferential direction and is disposed so as to surround the plurality of power modules from the outside in the radial direction, the power conversion device further includes a plurality of bus bars connecting the plurality of power modules to the plurality of coils, The rotating electric unit, wherein the plurality of bus bars have cutout portions formed in areas that face portions of the plurality of power modules.

16. a rotating electric machine including a stator, a rotor that rotates about an axis relative to the stator, and a plurality of coils wound around the stator; a power conversion device that is arranged alongside the rotating electric machine in an axial direction along an axis of the rotor, 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, When viewed from the axial direction, the capacitor unit extends in a circumferential direction and is disposed so as to surround the plurality of power modules from the outside in the radial direction, the power conversion device further includes a plurality of bus bars respectively connecting the plurality of power modules to the plurality of coils, a control board which controls the plurality of power modules, and a plurality of current sensors which respectively detect currents flowing through the plurality of bus bars; The rotating electrical machine unit, wherein each of the plurality of current sensors is directly connected to the control board.

17. a rotating electric machine including a stator, a rotor that rotates about an axis relative to the stator, and a plurality of coils wound around the stator; a power conversion device that is arranged alongside the rotating electric machine in an axial direction along an axis of the rotor, 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, When viewed from the axial direction, the capacitor unit extends in a circumferential direction and is disposed so as to surround the plurality of power modules from the outside in the radial direction, the power conversion device further includes a plurality of bus bars connecting the plurality of power modules to the plurality of coils, each of the plurality of bus bars has a first terminal connected to a corresponding one of the plurality of power modules and a second terminal connected to a corresponding one of the plurality of coils; The rotating electrical unit, wherein the first terminal is located radially inward of a main body of the corresponding power module.

18. a surface of one of the positive terminal and the positive conductor facing the rotating electric machine and a surface of the other of the positive terminal and the positive conductor facing away from the rotating electric machine are in contact with each other, The rotating electric unit according to claim 1, wherein a surface of either the negative terminal or the negative conductor facing the rotating electric machine and a surface of the other of the negative terminal or the negative conductor facing the rotating electric machine are in contact with each other.

19. a capacitor heat dissipation member is provided between the positive electrode side cooled portion and the negative electrode side cooled portion and the capacitor cooling portion, The rotating electrical unit according to claim 10 , 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 dissipation member.

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