Rotary electric machine unit

Abstract

To improve heat dissipation of a power conversion device by reducing the bias of an internal temperature distribution of a casing cover.SOLUTION: A rotary electric machine unit includes a rotary electric machine having a rotation shaft, and a power conversion device having a control substrate that is disposed next to the rotary electric machine in an axis direction along the axis of the rotation shaft and controls the rotary electric machine, and a casing cover that houses the control substrate. Inside the casing cover, an airflow generation structure for generating an airflow using a rotation operation of the rotation shaft is disposed. A leading end of the rotation shaft extends to the internal space of the casing cover. The airflow generation structure is fixed to the leading end of the rotation shaft.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present disclosure relates to a rotating electrical machine unit. [Background technology]

[0002] Conventionally, there has been known a rotating electric machine unit in which the entire device is miniaturized by integrating a rotating electric machine with a power conversion device. For example, in Patent Document 1, the tip of the rotating shaft is disposed inside the housing cover of the power conversion device, thereby miniaturizing the rotating electric machine unit. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6897813 Summary of the Invention [Problem to be solved by the invention]

[0004] When the tip of the rotating shaft is placed inside the housing cover of the power converter, heat generated by the operation of the rotating electric machine is transmitted to the power converter. Furthermore, electronic components of the power converter also generate heat when current is applied. The power converter is provided with a cooling structure for dissipating heat from the components placed inside the housing cover.

[0005] Among the components arranged inside the housing cover, those in contact with the cooling structure can directly dissipate heat through the cooling structure. Meanwhile, heat generated by components not in contact with the cooling structure is transferred to the cooling structure through the air inside the housing cover and the parts attached to the housing cover, and then dissipated to the outside of the rotating electric machine unit. Air has low thermal conductivity, and the internal space of the housing cover is sealed. Therefore, heat generated by components not in contact with the cooling structure is not easily transferred to the cooling structure and tends to accumulate around these components. As a result, in conventional rotating electric machine units, the temperature of components arranged inside the housing cover that are not in contact with the cooling structure remains high, resulting in an uneven temperature distribution inside the housing cover. There is a need to effectively transfer heat generated by components not in contact with the cooling structure to the cooling structure to improve the heat dissipation performance of the rotating electric machine unit.

[0006] The present disclosure has been made in consideration of the above-mentioned circumstances, and aims to provide a rotating electric unit that can reduce the imbalance in temperature distribution inside the housing cover and improve heat dissipation performance. [Means for solving the problem]

[0007] The rotating electric machine unit of the present disclosure comprises a rotating electric machine having a rotating shaft, a control board arranged alongside the rotating electric machine in an axial direction along the axis of the rotating shaft and controlling the rotating electric machine, and a housing cover accommodating the control board, wherein an airflow generating structure is provided inside the housing cover to generate airflow by utilizing the rotational movement of the rotating shaft, the tip of the rotating shaft extending into the internal space of the housing cover, and the airflow generating structure is fixed to the tip of the rotating shaft. [Effects of the Invention]

[0008] According to the present disclosure, it is possible to provide a rotating electrical unit that utilizes the rotational movement of a rotating shaft to reduce unevenness in the temperature distribution inside a housing cover and improve heat dissipation. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a perspective view of a rotary electric machine unit according to a first embodiment. [Figure 2] 1 is a circuit diagram of a rotary electric machine unit according to a first embodiment. [Figure 3] FIG. 2 is an exploded perspective view of the rotary electric machine unit according to the first embodiment. [Figure 4] 1 is a schematic cross-sectional view of a rotating electric machine according to a first embodiment. [Figure 5] 1 is a perspective view of a power conversion device according to a first embodiment. [Figure 6] 1 is a perspective view of a power conversion device according to a first embodiment, showing a state in which a control board and a drive board have been removed. [Figure 7] 1 is a perspective view of a rotation detection target and a rotation detection unit as an airflow generating structure according to a first embodiment. FIG. [Figure 8] FIG. 10 is a perspective view of an airflow generating structure according to a second embodiment. [Figure 9] FIG. 10 is a perspective view of an airflow generating structure according to a modified example of the second embodiment. [Figure 10] FIG. 11 is a perspective view of an airflow generating structure according to a third embodiment. [Figure 11] FIG. 10 is a perspective view of an airflow generating structure according to a fourth embodiment. [Figure 12] FIG. 11 is a perspective view of an airflow generating structure according to a fifth embodiment. [Figure 13] FIG. 13 is a perspective view of an airflow generating structure according to a sixth embodiment. [Figure 14] FIG. 20 is a perspective view of an airflow generating structure according to a modified example of the sixth embodiment. [Figure 15] FIG. 13 is a schematic cross-sectional view of an airflow generating structure according to a seventh embodiment. [Figure 16] FIG. 13 is a schematic cross-sectional view of an airflow generating structure according to an eighth embodiment. [Figure 17] FIG. 13 is a perspective view of an airflow generating structure according to a ninth embodiment. [Figure 18] 13A to 13C are diagrams illustrating the operation of the airflow generating structure according to the ninth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] <First Embodiment> Hereinafter, a rotating electrical machine unit 1 according to a first embodiment will be described with reference to the drawings. Fig. 1 is a perspective view of the rotating electrical machine unit 1. Fig. 2 is a circuit diagram of the rotating electrical machine unit 1.

[0011] 1, the rotating electrical machine unit 1 includes a rotating electrical machine 2 and a power converter 3. The rotating electrical machine 2 and the power converter 3 are integrated together. The rotating electrical machine unit 1 is mounted on, for example, a vehicle.

[0012] The power conversion device 3 has a housing cover 58 that houses electronic components and the like of the power conversion device 3. A DC power supply terminal block 10 is provided on the top surface of the housing cover 58. A signal connector 51 is provided on the side surface of the housing cover 58. The rotating electric machine unit 1 is connected to an on-board battery 4 (see FIG. 2 ) mounted on a vehicle via the DC power supply terminal block 10. Driving power is supplied to the rotating electric machine unit 1 from the on-board battery 4. The rotating electric machine unit 1 is also connected to an electric control unit mounted on the vehicle via the signal connector 51. The rotating electric machine unit 1 transmits and receives various signals required for controlling the rotating electric machine unit 1 to and from the electric control unit. The rotating electric machine unit 1 controls the rotating electric machine 2 in accordance with control commands from the electric control unit (i.e., operation commands requested by the vehicle).

[0013] The circuit configuration (electrical configuration) of the rotating electrical machine unit 1 will be described with reference to Fig. 2. In this embodiment, the rotating electrical machine unit 1 is a dual three-phase drive system having two sets of three-phase inverter circuits. The dual three phases are U1 phase, V1 phase, W1 phase, U2 phase, V2 phase, and W2 phase. DC power is input to the power conversion device 3 from the vehicle-mounted battery 4 via a DC power supply terminal block 10. The power conversion device 3 converts the DC power input from the vehicle-mounted battery 4 into AC power and supplies it to the rotating electrical machine 2.

[0014] The rotating electric machine 2 is a dual three-phase drive motor and includes six motor windings 32 provided corresponding to the dual three phases (U1 phase, V1 phase, W1 phase, U2 phase, V2 phase, and W2 phase).

[0015] The power conversion device 3 includes an inverter 8, a capacitor module 11, a control board 5, and a drive board 16.

[0016] The capacitor module 11 is provided on the input side of the inverter 8. The capacitor module 11 is a smoothing capacitor that stabilizes the voltage supplied from the vehicle-mounted battery 4 so that it does not fluctuate greatly.

[0017] The inverter 8 has six power modules 9 provided corresponding to each of the dual three phases (U1 phase, V1 phase, W1 phase, U2 phase, V2 phase, and W2 phase). The three power modules 9 corresponding to the U1 phase, V1 phase, and W1 phase are connected in parallel to form a first three-phase AC full-bridge circuit. The three power modules 9 corresponding to the U2 phase, V2 phase, and W2 phase are connected in parallel to form a second three-phase AC full-bridge circuit.

[0018] The power module 9 includes a pair of power semiconductors 9a and 9b connected in series. The power semiconductors 9a and 9b are, for example, insulated gate bipolar transistors (IGBTs) or metal oxide semiconductor field effect transistors (MOSFETs).

[0019] The power module 9 is electrically connected to the motor winding 32 of the corresponding phase of the rotating electric machine 2 via the relay bus bar 13 and the power feed line 34. Specifically, an end of the motor winding 32 is connected to the power feed line 34. The power feed line 34 may be an end (lead wire) of the motor winding 32. An end of the power feed line 34 is connected to one end of the relay bus bar 13. The other end of the relay bus bar 13 is connected to an output terminal of the power module 9. The power module 9 supplies power to the motor winding 32 of the corresponding phase of the rotating electric machine 2.

[0020] The power conversion device 3 includes six current detection units 12 provided corresponding to each of the dual three phases (U1 phase, V1 phase, W1 phase, U2 phase, V2 phase, and W2 phase). The current detection units 12 are attached to the relay bus bars 13 of the corresponding phases. Note that FIG. 2 shows only the current detection unit 12 for the W1 phase. The current detection units 12 detect the current flowing through the motor windings 32 by sensing the current flowing through the relay bus bars 13.

[0021] The power conversion device 3 includes a temperature detection unit 6 and a rotation detection unit 7. The temperature detection unit 6 and the rotation detection unit 7 are mounted on the control board 5. The temperature detection unit 6 detects the temperature of the motor windings 32 by sensing the temperature of the power supply line 34. The rotation detection unit 7 detects the rotation speed of the rotor 31 of the rotating electric machine 2.

[0022] The control board 5 includes a control circuit for controlling the operation of the inverter 8. Control commands are input to the control board 5 from the electric control unit via a signal connector 51. Detection results from the rotation detector 7, current detector 12, etc. are also input to the control board 5. The detection results from the rotation detector 7, current detector 12, etc. make it possible to grasp the operating state of the rotating electric machine 2. Based on the detection results from the rotation detector 7, current detector 12, etc., the control board 5 drives and controls the inverter 8 so that the rotating electric machine 2 operates at a rotation speed and torque in accordance with the control commands from the electric control unit.

[0023] The drive board 16 includes a drive circuit for driving the power module 9. The drive board 16 amplifies a drive signal output from the control board 5 and inputs the amplified signal to a control terminal of the power module 9. The drive board 16 drives the inverter 8 by switching the power semiconductors 9a and 9b of the power module 9 between an on state and an off state.

[0024] Next, the structure of the rotating electrical machine unit 1 will be described with reference to FIGS. In this specification, the direction along the axis O (see FIG. 4) of the rotor 31 of the rotating electric machine 2 is referred to as the "axial direction Z." Also, the direction intersecting the axis O of the rotor 31 as viewed from the axial direction Z is referred to as the "radial direction," and the direction going around the axis O of the rotor 31 is referred to as the "circumferential direction." 1, the rotating electric machine 2 and the power conversion device 3 are aligned in the axial direction Z. In the axial direction Z, the side where the power conversion device 3 is located is referred to as the +Z side or upper side, and the side where the rotating electric machine 2 is located is referred to as the -Z side or lower side.

[0025] 4 is a cross-sectional view of the rotating electric machine 2. As shown in FIG. 4, the rotating electric machine 2 includes a rotor 31, a bracket 33, a rotating shaft 35, a rotation detection target 36, and a motor housing 38.

[0026] The motor housing 38 is cylindrical and has a bottom. The motor housing 38 accommodates the rotor 31, the rotary shaft 35, and a stator (not shown) wound with the motor windings 32. The end of the motor housing 38 on the +Z side is closed by a bracket 33.

[0027] The rotor 31 is provided inside the motor housing 38. A magnet (not shown) is provided on the rotor 31. The rotor 31 is rotatable about an axis O relative to the motor housing 38.

[0028] The rotating shaft 35 is attached to the rotor 31. The rotating shaft 35 is rotatably supported by bearings (not shown) provided on the bottom of the motor housing 38 and the bracket 33. As shown in FIG. 3, the tip 35a (end on the +Z side) of the rotating shaft 35 penetrates the bracket 33 and protrudes toward the power conversion device 3 (+Z side). The tip 35a of the rotating shaft 35 is disposed inside the housing cover 58. This allows the rotating electric machine unit 1 to be made smaller in the axial direction Z.

[0029] The rotation detection target 36 is attached to the tip 35a of the rotation shaft 35. The rotation detection target 36 rotates with the rotation of the rotation shaft 35. Details of the rotation detection target 36 will be described later.

[0030] The power supply line 34 is connected to an end of the motor winding 32. As shown in Fig. 3, the power supply line 34 passes through the bracket 33 and protrudes to the power converter 3 side (+Z side).

[0031] The bracket 33 faces the power converter 3. The bracket 33 separates the internal space of the motor housing 38 from the internal space of the housing cover 58. A flange portion 58a that abuts against the bracket 33 is formed on the end of the housing cover 58 on the -Z side. The bracket 33 is fixed to the flange portion 58a using fixing screws 57 (see FIG. 1). In this way, the power converter 3 is fixed to the rotating electric machine 2.

[0032] A large current flows through the motor windings 32 of the rotating electric machine 2. The rotating electric machine 2 generates heat when current is applied to the motor windings 32, and therefore has a cooling structure for heat dissipation. Specifically, as shown in FIG. 1 , the rotating electric machine 2 is provided with a cooling oil inlet 54 through which cooling oil flows, a cooling oil outlet 55 through which the cooling oil flows out, and a flow path (not shown) connecting the cooling oil inlet 54 and the cooling oil outlet 55. The cooling oil that flows in from the cooling oil inlet 54 is sprayed onto the motor windings 32 and the rotor 31, cooling the motor windings 32 and the rotor 31. The cooling oil that has received heat by cooling the motor windings 32 and the rotor 31 flows through the flow path and flows out from the cooling oil outlet 55. As shown in FIG. 4 , in order to prevent the cooling oil from leaking outside the rotating electric machine 2, a packing 39 is provided between the bracket 33 and the motor housing 38, and an oil seal 40 is provided between the rotating shaft 35 and the bracket 33.

[0033] Fig. 5 is a perspective view of the power conversion device 3. In order to explain the positional relationship with the rotating electric machine 2, Fig. 5 also shows the rotating shaft 35 of the rotating electric machine 2, the rotation detection target 36, and the power supply line 34. Fig. 6 is a perspective view of the power conversion device 3, showing a state in which the control board 5 and the drive board 16 have been removed.

[0034] 5 and 6, the housing cover 58 accommodates the control board 5, the drive board 16, the power module 9, the capacitor module 11, and the like. Inside the housing cover 58, the control board 5, the drive board 16, and the power module 9 are arranged in this order from the -Z side to the +Z side. In the illustrated example, two drive boards 16 are provided, but the number of drive boards 16 may be one, or three or more.

[0035] A plurality of temperature sensors 22 are mounted on the control board 5. The temperature sensors 22 are, for example, thermistors. The plurality of temperature sensors 22 measure the temperature at a plurality of locations inside the housing cover 58. The plurality of temperature sensors 22 can measure the temperature distribution inside the housing cover 58. A control terminal of the power module 9 is connected to the drive board 16. The drive board 16 has a current detection unit 12 attached thereto.

[0036] The power converter 3 has a terminal block 17 that connects the power feeder 34 and the relay bus bar 13. The power feeder 34 is inserted into the terminal block 17 and fixed with a screw (not shown). Terminal fixing holes 56 for screw fastening are formed on the side of the housing cover 58. Note that the rotating electric machine 2 and the power converter 3 can be separated by removing the fixing screws 57 that fix the bracket 33 to the housing cover 58 and the screws that fix the power feeder 34.

[0037] The rotation detection target 36 and the rotation detection unit 7 will be described with reference to FIG. The rotation detection target 36 is made of a conductive non-magnetic metal. The rotation detection target 36 has a cylindrical mounting tube portion 36a and a plurality of terminal portions 36b protruding radially outward from the mounting tube portion 36a. The mounting tube portion 36a is attached to the tip portion 35a of the rotation shaft 35. The plurality of terminal portions 36b are arranged at equal intervals in the circumferential direction.

[0038] The rotation detection unit 7 is mounted on the surface of the control board 5 facing the rotating electric machine 2 (the surface facing the -Z side). The rotation detection unit 7 is arranged to face the rotation detection target 36 in the axial direction Z. The rotation detection target 36 and the rotation detection unit 7 are arranged in close proximity. The rotation detection target 36 is not in contact with the rotation detection unit 7. The rotation detection target 36 rotates relative to the rotation detection unit 7 as the rotating shaft 35 rotates. The rotation speed of the rotor 31 of the rotating electric machine 2 is detected by counting the number of times the terminal portion 36b of the rotation detection target 36 passes through the sensing position of the rotation detection unit 7. Note that the power required to drive the rotating electric machine 2 is large enough to drive a vehicle or the like, and the power required to rotate the rotation detection target 36 is negligibly small compared to this power.

[0039] Specifically, the rotation detection unit 7 has a pattern coil 21. The pattern coil 21 is composed of a transmitting coil that generates an AC magnetic field and a receiving coil that receives the AC magnetic field generated by the transmitting coil. The receiving coil faces the rotation detection target 36 in the axial direction Z. When viewed from the axial direction Z, the receiving coil is disposed radially inside the rotation detection target 36. When the AC magnetic field generated by the transmitting coil interlinks with the receiving coil in the pattern coil 21, an induced voltage is generated at the end of the receiving coil. This induced voltage is synchronized with the position of the rotation detection target 36, i.e., changes periodically according to the rotation of the rotation detection target 36. The rotation speed of the rotor 31 of the rotating electric machine 2 can be measured by measuring the frequency of the induced voltage in the rotation detection unit 7 using the control board 5.

[0040] Components arranged inside the housing cover 58 (e.g., the power module 9, the control board 5, the capacitor module 11, the drive board 16, and the power feeder 34) generate heat as the rotating electric machine unit 1 operates. The power conversion device 3 is provided with a cooling structure C for dissipating heat from the components arranged inside the housing cover 58. Specifically, the cooling structure C has a cooling water inlet 52 and a cooling water outlet 53 shown in FIG. 1 and a water channel 19 shown in FIG. 5. The cooling water inlet 52, the cooling water outlet 53, and the water channel 19 are provided in the housing cover 58. Cooling water flows in through the cooling water inlet 52 and flows out through the cooling water outlet 53. The water channel 19 is connected to the cooling water inlet 52 and the cooling water outlet 53. The cooling water that flows in from the cooling water inlet 52 cools the components arranged inside the housing cover 58 while flowing through the water channel 19. The cooling water that has received heat by cooling the components arranged inside the housing cover 58 flows out from the cooling water outlet 53.

[0041] Here, a large current flows through the power module 9, and therefore the power module 9 generates a large amount of heat. The cooling structure C of the power conversion device 3 has a cooling surface 18 formed on the inner surface of the housing cover 58, and the power module 9 (inverter 8) is placed on the cooling surface 18. The cooling surface 18 is provided on the opposite side of the tip portion 35a of the rotating shaft 35 in the axial direction Z, with the control board 5 in between. The cooling surface 18 is in contact with the power module 9 (inverter 8). The cooling surface 18 is made of a material with high thermal conductivity, such as metal. The water channel 19 is formed to pass near the cooling surface 18. Heat generated in the power module 9 is transferred to the cooling surface 18 and dissipated to the outside of the rotating electrical machine unit 1 through cooling water flowing through the water channel 19.

[0042] As described above, the power module 9 is disposed on the cooling surface 18, and therefore heat can be dissipated directly through the cooling surface 18. On the other hand, the control board 5, the capacitor module 11, the drive board 16, the power feed line 34, and the like are not in contact with the cooling surface 18. Heat generated by the control board 5, the capacitor module 11, the drive board 16, the power feed line 34, and the like is transferred to the cooling surface 18 via the air inside the housing cover 58 and the parts fixed to the housing cover 58, and is then dissipated to the outside of the rotating electrical machine unit 1. The thermal conductivity of air is much lower than that of the cooling surface 18 and the housing cover 58. In addition, the internal space of the housing cover 58 is sealed by the bracket 33, and air does not circulate between the inside and outside of the housing cover 58. Therefore, heat generated by the control board 5, the capacitor module 11, the drive board 16, the power feed line 34, and the like is not easily transferred to the cooling surface 18 (cooling structure C) and tends to accumulate around these components. As a result, in conventional rotating electric units, the temperatures of components that are not in contact with the cooling structure, such as the control board, capacitor module, drive board, and power supply line, remain high, causing an imbalance in the temperature distribution inside the housing cover.

[0043] The rotating electrical machine unit 1 is provided with an airflow generating structure 60 that generates an airflow in the internal space of the housing cover 58. In this embodiment, the rotation detection target 36 functions as the airflow generating structure 60. More specifically, the multiple terminals 36b of the rotation detection target 36 rotate in conjunction with the rotation of the rotary shaft 35, generating an airflow in the internal space of the housing cover 58. This agitates the air within the housing cover 58, causing air to circulate within the housing cover 58. For example, low-temperature air around the cooling surface 18 and the housing cover 58 is blown toward high-temperature components such as the control board 5, the capacitor module 11, the drive board 16, and the power feed line 34, thereby cooling these components. Furthermore, the air that has received heat by cooling the control board 5, the capacitor module 11, the drive board 16, and the power feed line 34 flows toward the cooling surface 18 and comes into contact with the cooling surface 18 to be cooled. In this way, air circulates inside the housing cover 58, so that heat generated by components that are not in contact with the cooling structure C, such as the control board 5, capacitor module 11, drive board 16, and power supply line 34, can be effectively transferred to the cooling surface 18 (cooling structure C). As a result, it is possible to reduce unevenness in the temperature distribution inside the housing cover 58, and improve the heat dissipation performance of the rotating electrical machine unit 1.

[0044] Furthermore, when the driving output of the rotating electric machine 2 increases and the rotation speed of the rotating shaft 35 increases, the amount of heat generated by each component of the rotating electric machine unit 1 also increases. However, as the rotation speed of the rotating shaft 35 increases, the volume of the airflow generated by the rotation detection target 36 also increases. Therefore, air circulation inside the housing cover 58 is promoted, and the heat dissipation performance of the rotating electric machine unit 1 can be improved.

[0045] As described above, the rotating electric machine unit 1 according to this embodiment includes the rotating electric machine 2 having the rotating shaft 35, the control board 5 arranged alongside the rotating electric machine 2 in the axial direction Z and controlling the rotating electric machine 2, and the power conversion device 3 having the housing cover 58 accommodating the control board 5. An airflow generating structure 60 that generates airflow by utilizing the rotational movement of the rotating shaft 35 is provided inside the housing cover 58. The tip end 35a of the rotating shaft 35 extends into the internal space of the housing cover 58. The airflow generating structure 60 is fixed to the tip end 35a of the rotating shaft 35.

[0046] An airflow generating structure 60 that generates an airflow inside the housing cover 58 is provided, so that air can be circulated inside the housing cover 58. As a result, by utilizing the rotational movement of the rotating shaft 35, it is possible to reduce unevenness in the temperature distribution inside the housing cover 58, and improve the heat dissipation performance of the rotating electrical machine unit 1.

[0047] The power conversion device 3 also has an inverter 8 housed in a housing cover 58, and a cooling structure C that cools the inverter 8. The cooling structure C is provided on the opposite side of the tip portion 35a of the rotating shaft 35 across the control board 5 in the axial direction Z, and has a cooling surface 18 that comes into contact with the inverter 8. According to the above configuration, heat generated by the control board 5 and the like can be effectively transferred to the cooling surface 18 (cooling structure C) by circulating air inside the housing cover 58. Therefore, the uneven temperature distribution inside the housing cover 58 can be more effectively reduced.

[0048] The rotating electric machine 2 also has a rotation detection target 36 attached to the tip 35a of the rotating shaft 35. The power conversion device 3 has a rotation detection unit 7 that is disposed opposite the rotation detection target 36 in the axial direction Z and detects the rotation of the rotation detection target 36. The airflow generating structure 60 includes the rotation detection target 36. According to the above configuration, the rotation detection target 36 attached to the tip 35a of the rotating shaft 35 functions as an airflow generating structure 60, and by rotating together with the rotating shaft 35, an airflow can be generated inside the housing cover 58.

[0049] <Embodiment 2> Next, a rotating electrical machine unit according to the second embodiment will be described with reference to Fig. 8. The rotating electrical machine unit according to this embodiment has the same basic configuration as the rotating electrical machine unit according to the first embodiment, and therefore differences will be mainly described.

[0050] As shown in FIG. 8, in this embodiment, the airflow generating structure 60 includes a flat fan 61 having a plurality of flat blades 61a. The plurality of flat blades 61a are attached to the plurality of terminal portions 36b of the rotation detection target 36, respectively. The upper surfaces of the flat blades 61a are inclined with respect to a plane perpendicular to the axial direction Z. The upper surfaces of the flat blades 61a have a curved shape such that rotation of the flat fan 61 generates an airflow toward the -Z side inside the housing cover 58. The lower surfaces of the flat blades 61a are disposed adjacent to the control board 5, and therefore form a plane that is aligned with the control board 5. The flat fan 61 is fixed to the rotation shaft 35 via the rotation detection target 36.

[0051] The flat fan 61 rotates in conjunction with the rotation of the rotary shaft 35, generating an airflow in the internal space of the housing cover 58. Specifically, when the flat fan 61 rotates, an airflow toward the -Z side is generated in the internal space of the housing cover 58. This causes air to circulate inside the housing cover 58, and heat generated by components that are not in contact with the cooling structure C, such as the control board 5, capacitor module 11, drive board 16, and power feeder 34, can be effectively transferred to the cooling surface 18 (cooling structure C). As a result, it is possible to reduce unevenness in the temperature distribution inside the housing cover 58, and improve the heat dissipation performance of the rotating electrical machine unit 1.

[0052] In the illustrated example, the flat fan 61 (flat blades 61a) is configured to generate an airflow toward the -Z side when the rotating shaft 35 rotates clockwise as viewed from the -Z side. If the rotating shaft 35 rotates counterclockwise as viewed from the -Z side, the inclination direction of the flat blades 61a may be opposite to that in the illustrated example. The shape and number of the flat blades 61a may be changed as appropriate depending on the specifications of the rotating electrical machine unit 1, etc.

[0053] As described above, in the rotating electrical machine unit 1 according to this embodiment, the airflow generating structure 60 includes the flat fan 61 having a plurality of flat blades 61a attached to the rotation detection target . According to the above configuration, the flat fan 61 rotates in conjunction with the rotation of the rotary shaft 35, and can generate an airflow inside the housing cover 58 more effectively.

[0054] <Modification of the second embodiment> 9, the flat fan 61 may have a plurality of flat blades 61b instead of the flat blade 61a. The lower surfaces 61b1 of the flat blades 61b (the surfaces of the flat blades 61b facing the rotation detection unit 7 in the axial direction Z) have a curved shape such that rotation of the flat fan 61 generates an airflow toward the +Z side inside the housing cover 58. That is, the flat blades 61b are configured such that the distance between the rotation detection unit 7 and the lower surfaces 61b1 in the axial direction Z changes in the circumferential direction. According to the flat fan 61 of this modification, when the flat fan 61 rotates, an airflow toward the +Z side (i.e., the control board 5 side) can be generated in the internal space of the housing cover 58.

[0055] <Third Embodiment> Next, a rotating electrical machine unit according to a third embodiment will be described with reference to Fig. 10. The rotating electrical machine unit according to this embodiment has the same basic configuration as the rotating electrical machine unit according to the first embodiment, and therefore differences will be mainly described.

[0056] In this embodiment, as shown in Fig. 10, the airflow generating structure 60 includes an oblique fan 62 having a plurality of oblique blades 62a. The plurality of oblique blades 62a are attached to the outer peripheral surface of the tip end 35a of the rotating shaft 35. The plurality of oblique blades 62a are provided at intervals in the circumferential direction. The oblique blades 62a are inclined with respect to the axial direction Z.

[0057] The oblique fan 62 rotates in conjunction with the rotation of the rotary shaft 35, generating an airflow in the internal space of the housing cover 58. Specifically, when the oblique fan 62 rotates, an airflow toward the +Z side is generated in the internal space of the housing cover 58. This agitates the air inside the housing cover 58, circulating the air inside the housing cover 58 and effectively transferring heat generated by components that are not in contact with the cooling structure C, such as the control board 5, capacitor module 11, drive board 16, and power feeder 34, to the cooling surface 18 (cooling structure C). As a result, it is possible to reduce unevenness in the temperature distribution inside the housing cover 58 and improve the heat dissipation performance of the rotating electrical machine unit 1.

[0058] Furthermore, when the driving output of the rotating electric machine 2 increases and the rotation speed of the rotating shaft 35 increases, the amount of heat generated by each component of the rotating electric machine unit 1 also increases. However, as the rotation speed of the rotating shaft 35 increases, the airflow rate generated by the oblique fan 62 also increases. This promotes air circulation inside the housing cover 58, thereby improving the heat dissipation performance of the rotating electric machine unit 1.

[0059] In the illustrated example, the oblique fan 62 (oblique blades 62a) is configured to generate an airflow toward the +Z side when the rotating shaft 35 rotates clockwise as viewed from the -Z side. If the rotating shaft 35 rotates counterclockwise as viewed from the -Z side, the inclination direction of the oblique blades 62a may be opposite to that in the illustrated example. The shape and number of the oblique blades 62a may be changed as appropriate depending on the specifications of the rotating electrical machine unit 1, etc.

[0060] As described above, in the rotating electrical machine unit 1 according to this embodiment, the airflow generating structure 60 includes an oblique fan 62 having a plurality of oblique blades 62a attached to the outer peripheral surface of the tip end 35a of the rotating shaft 35. According to the above configuration, the oblique fan 62 rotates in conjunction with the rotation of the rotary shaft 35, and can generate an airflow inside the housing cover 58 more effectively.

[0061] <Fourth Embodiment> Next, a rotating electrical machine unit according to embodiment 4 will be described with reference to Fig. 11. The rotating electrical machine unit according to this embodiment has the same basic configuration as the rotating electrical machine unit according to embodiment 3, and therefore differences will be mainly described.

[0062] As shown in FIG. 11 , in this embodiment, the airflow generating structure 60 includes an oblique fan 62 and a cylindrical cover 63 that surrounds the oblique fan 62. The cylindrical cover 63 is cylindrical and houses the oblique fan 62. The cylindrical cover 63 is fixed to, for example, the housing cover 58. The cylindrical cover 63 does not rotate even when the rotating shaft 35 and the oblique fan 62 rotate. The airflow generated by the oblique fan 62 passes through the gap between the rotating shaft 35 and the cylindrical cover 63 and is ejected from an opening on the +Z side of the cylindrical cover 63. The provision of the cylindrical cover 63 allows the airflow generated by the oblique fan 62 to be ejected toward the +Z side without diffusing radially outward from the rotating shaft 35. This promotes air circulation inside the housing cover 58 and effectively reduces uneven temperature distribution inside the housing cover 58. Furthermore, the airflow generated by the oblique fan 62 passes through the gap between the rotating shaft 35 and the cylindrical cover 63, thereby also cooling the rotating shaft 35. The length of the cylindrical cover 63 in the axial direction Z can be changed as appropriate depending on the direction and position from which the airflow is desired to be ejected.

[0063] As described above, in this embodiment, the airflow generating structure 60 further includes the cylindrical cover 63 provided so as to surround the oblique fan 62 . According to the above configuration, the airflow generated by the oblique fan 62 can be ejected in the axial direction Z without diffusing radially outward from the rotating shaft 35. This promotes air circulation inside the housing cover 58, and effectively reduces uneven temperature distribution inside the housing cover 58.

[0064] <Fifth Embodiment> Next, a rotating electrical machine unit according to embodiment 5 will be described with reference to Fig. 12. The rotating electrical machine unit according to this embodiment has the same basic configuration as the rotating electrical machine units according to embodiments 2 and 4, and therefore differences will be mainly described.

[0065] As shown in Fig. 12, this embodiment combines the second and fourth embodiments. That is, an airflow generating structure 60 according to this embodiment includes a flat fan 61, an oblique fan 62, and a cylindrical cover 63. The flat fan 61 and the oblique fan 62 rotate in conjunction with the rotation of the rotary shaft 35, thereby more effectively stirring the air inside the housing cover 58. This makes it possible to more effectively reduce the unevenness of the temperature distribution inside the housing cover 58, and improve the heat dissipation performance of the rotating electrical machine unit 1.

[0066] <Sixth Embodiment> Next, a rotating electrical machine unit according to Embodiment 6 will be described with reference to Fig. 13. The rotating electrical machine unit according to this embodiment has the same basic configuration as the rotating electrical machine unit according to Embodiment 2, and therefore differences will be mainly described.

[0067] As shown in Fig. 13, in this embodiment, an airflow generating structure 60 includes, in addition to a flat fan 61, an air guide cover 64 that is provided to cover the flat fan 61. The air guide cover 64 is provided with an outlet 64a through which the airflow generated by the flat fan 61 is ejected. By providing the outlet 64a, it is possible to adjust the ejection direction of the airflow generated by the flat fan 61. Note that the air guide cover 64 may be provided with multiple outlets 64a.

[0068] <Modification of the Sixth Embodiment> 14, the air guide cover 64 may have air guide nozzles 64b, 64c with an outlet 64a formed at the tip. The air guide nozzle 64b is curved so that the airflow is ejected from the outlet 64a toward the power feeder 34. The air guide nozzle 64c is curved so that the airflow is ejected from the outlet 64a toward the capacitor module 11. By providing the air guide nozzles 64b, 64c, the airflow generated by the flat fan 61 can be ejected directly toward components that tend to become hot, such as the power feeder 34 and the capacitor module 11. This makes it possible to more effectively reduce uneven temperature distribution inside the housing cover 58 and improve the heat dissipation performance of the rotating electrical machine unit 1.

[0069] As described above, in the rotating electric machine unit 1 according to this embodiment, the airflow generating structure 60 further includes an air guide cover 64 that is arranged to cover the flat fan 61, and the air guide cover 64 is provided with an outlet 64a through which the airflow generated by the flat fan 61 is ejected. According to the above configuration, the direction in which the airflow generated by the flat fan 61 is blown out can be adjusted.

[0070] <Seventh Embodiment> Next, a rotating electrical machine unit according to the seventh embodiment will be described with reference to Fig. 15. The rotating electrical machine unit according to this embodiment has the same basic configuration as the rotating electrical machine unit according to the fourth embodiment, and therefore differences will be mainly described.

[0071] As shown in FIG. 15 , in this embodiment, the airflow generating structure 60 further includes an inlet cover 65 in addition to the oblique fan 62 and the cylindrical cover 63. The inlet cover 65 is attached to the −Z-side end of the cylindrical cover 63. The inlet cover 65 is a tapered cylinder whose diameter increases toward the −Z side. The inlet cover 65 is fixed to the housing cover 58 by a fixing member 66. When the oblique fan 62 rotates, low-temperature air around the housing cover 58 is sucked in through the inlet cover 65. The air sucked in through the inlet cover 65 passes through the gap between the rotation shaft 35 and the cylindrical cover 63 and is ejected from the opening on the +Z side of the cylindrical cover 63. The provision of the inlet cover 65 allows the low-temperature air around the housing cover 58 to be taken in by the airflow generating structure 60, thereby circulating the low-temperature air inside the housing cover 58. This more effectively reduces uneven temperature distribution inside the housing cover 58.

[0072] In this embodiment, the tip 35a of the rotating shaft 35 penetrates the control board 5 and extends between the control board 5 and the drive board 16. The airflow generating structure 60 includes a second flat fan 67 disposed between the control board 5 and the drive board 16. The second flat fan 67 has a plurality of second flat blades 67a attached to the outer circumferential surface of the tip 35a of the rotating shaft 35. The second flat fan 67 rotates with the rotation of the rotating shaft 35, generating an airflow in the space between the control board 5 and the drive board 16. Air tends to stagnate between the control board 5 and the drive board 16. By providing the second flat fan 67, air can be agitated in the space between the control board 5 and the drive board 16, more effectively reducing uneven temperature distribution inside the housing cover 58.

[0073] In addition, by reversing the rotation direction of the rotating shaft 35, air can be sucked in between the control board 5 and the drive board 16, and this air can be blown out from the suction cover 65 through the gap between the rotating shaft 35 and the cylindrical cover 63. Furthermore, the tip 35a of the rotating shaft 35 may be extended through the control board 5 and the drive board 16 to the space between the drive board 16 and the power module 9, and the second flat fan 67 may be disposed between the drive board 16 and the power module 9. In this case, the second flat fan 67 generates an airflow in the space between the drive board 16 and the power module 9, and the air in the space between the drive board 16 and the power module 9 can be agitated.

[0074] <Embodiment 8> Next, a rotating electrical machine unit according to an eighth embodiment will be described with reference to Fig. 16. The rotating electrical machine unit according to this embodiment has the same basic configuration as the rotating electrical machine units according to the sixth and seventh embodiments, and therefore differences will be mainly described.

[0075] As shown in Fig. 14, this embodiment combines the sixth and seventh embodiments. That is, an airflow generating structure 60 according to this embodiment includes a flat fan 61, an oblique fan 62, a cylindrical cover 63, a wind guide cover 64, an intake cover 65, and a second flat fan 67. In this embodiment, the flat fan 61 has a plurality of flat blades 61b (see Fig. 9), and is configured so that rotation of the flat fan 61 generates an airflow toward the +Z side inside the housing cover 58.

[0076] Furthermore, in this embodiment, the tip 35a of the rotating shaft 35 penetrates the control board 5 and the drive board 16, and extends to between the drive board 16 and the power module 9. A circulation passage is formed inside the tip 35a of the rotating shaft 35, extending in the axial direction Z and opening at the end face on the +Z side of the rotating shaft 35. Furthermore, an opening communicating with the circulation passage is formed in a portion of the tip 35a of the rotating shaft 35 that is located on the -Z side of the suction cover 65. As a result, air flows into the circulation passage from the opening and is ejected from the end face on the +Z side of the rotating shaft 35 between the drive board 16 and the power module 9.

[0077] In this embodiment, the air flows inside housing cover 58, for example, as follows. That is, low-temperature air around housing cover 58 is taken in through suction cover 65. This air is agitated by flat fan 61 and oblique fan 62, passes through the gap between rotating shaft 35 and cylindrical cover 63, flows along control board 5, and is ejected from outlet 64a. Between control board 5 and drive board 16, air is agitated by second flat fan 67 and flows along drive board 16. In addition, low-temperature air around housing cover 58 passes through a flow passage formed inside tip end 35a of rotating shaft 35 and is ejected from the end face on the +Z side of rotating shaft 35. The air that has flowed along control board 5, the air that has flowed along drive board 16, and the air that has been ejected from the end face on the +Z side of rotating shaft 35 flow in the -Z direction along the side of housing cover 58 and is again sucked in through suction cover 65. By circulating air inside the housing cover 58 as described above, the uneven temperature distribution inside the housing cover 58 can be reduced more effectively.

[0078] <Ninth Embodiment> Next, a rotating electrical machine unit according to embodiment 9 will be described with reference to Figures 17 and 18. The rotating electrical machine unit according to this embodiment has the same basic configuration as the rotating electrical machine unit according to embodiment 6, and therefore differences will be mainly described.

[0079] As shown in Figures 17 and 18, in this embodiment, a plurality of air outlets 64a are provided in the air guide cover 64, and each of the plurality of air outlets 64a is provided with an opening / closing structure 68 that opens and closes the air outlet 64a. The opening / closing structures 68 are connected to the control board 5 via an opening / closing structure control line 69. The control board 5 transmits an ON signal or an OFF signal to each opening / closing structure 68. When an ON signal is input from the control board 5, the opening / closing structure 68 operates to close the air outlet 64a. When an OFF signal is input from the control board 5, the opening / closing structure 68 operates to open the air outlet 64a.

[0080] The control board 5 controls the opening and closing structure 68 based on the detection results of the multiple temperature sensors 22, and adjusts the direction of the airflow generated by the flat fan 61 so that the airflow is directed toward the high-temperature part inside the housing cover 58. For example, the power conversion device 3 has six power modules 9, but under low load conditions, only three power modules 9 may be driven. In this case, the temperature distribution inside the housing cover 58 becomes more uneven. Furthermore, the temperature distribution inside the housing cover 58 may change due to variations in the operating conditions of the rotating electrical machine unit 1 or variations in the characteristics of the components disposed inside the housing cover 58. Even in such cases, by controlling the opening / closing structure 68 based on the detection results of the multiple temperature sensors 22, the airflow generated by the flat fan 61 can be directed toward the high-temperature portion inside the housing cover 58. This effectively reduces the uneven temperature distribution inside the housing cover 58.

[0081] As described above, in the rotary electric machine unit 1 according to this embodiment, the plurality of air outlets 64a are each provided with an opening / closing structure 68 that opens and closes the air outlet 64a. The control board 5 controls the opening / closing structure 68 based on the detection results of the plurality of temperature sensors 22. According to the above configuration, by controlling the opening / closing structure 68 based on the detection results of the plurality of temperature sensors 22, it is possible to effectively reduce the imbalance in the temperature distribution inside the housing cover 58.

[0082] 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.

[0083] For example, the rotating electrical machine unit 1 may be a rotating electrical machine unit of a single three-phase drive system, or may be a rotating electrical machine unit of a multi-phase drive system with six or more phases.

[0084] In addition, the above-described embodiments and modifications may be combined as appropriate.

[0085] Various aspects of the present disclosure are summarized below as appendices.

[0086] (Appendix 1) a rotating electric machine having a rotating shaft; a power conversion device including: a control board arranged alongside the rotating electric machine in an axial direction along an axis of the rotating shaft and controlling the rotating electric machine; and a housing cover accommodating the control board; Equipped with an airflow generating structure that generates an airflow by utilizing the rotational movement of the rotation shaft is provided inside the housing cover; a tip end of the rotation shaft extends to an internal space of the housing cover, The airflow generating structure is fixed to the tip end of the rotating shaft. Rotating electric unit.

[0087] (Appendix 2) the power conversion device includes an inverter housed in the housing cover and a cooling structure that cools the inverter, The rotating electric unit according to claim 1, wherein the cooling structure is provided on the opposite side of the tip of the rotating shaft across the control board in the axial direction, and has a cooling surface that contacts the inverter.

[0088] (Appendix 3) the rotating electric machine has a rotation detection target attached to a tip end of the rotating shaft, the power conversion device includes a rotation detection unit that is provided opposite to the rotation detection target in the axial direction and detects rotation of the rotation detection target, 3. The rotating electrical unit according to claim 1, wherein the airflow generating structure includes the rotation detection target.

[0089] (Appendix 4) 4. The rotating electric unit according to claim 3, wherein the airflow generating structure comprises a flat fan having a plurality of flat blades attached to the rotation detection target.

[0090] (Appendix 5) A rotating electric unit as described in Appendix 4, wherein each of the plurality of flat blades has an opposing surface facing the rotation detection unit in the axial direction, and the distance in the axial direction between the rotation detection unit and the opposing surface is configured to change circumferentially.

[0091] (Appendix 6) 6. The rotating electrical unit according to any one of claims 1 to 5, wherein the airflow generating structure includes an oblique fan having a plurality of oblique blades attached to the outer peripheral surface of the tip of the rotating shaft.

[0092] (Appendix 7) 7. The rotating electrical machine unit according to claim 6, wherein the airflow generating structure further includes a cylindrical cover provided to surround the oblique fan.

[0093] (Appendix 8) the airflow generating structure further includes a wind guide cover provided to cover the flat fan, The rotating electrical machine unit according to claim 4, wherein the air guide cover is provided with an outlet through which the airflow generated by the flat fan is ejected.

[0094] (Appendix 9) the power conversion device includes a plurality of temperature sensors for detecting a temperature inside the housing cover, The rotating electric unit of Appendix 8, wherein the air guide cover is provided with a plurality of outlets including the outlet, each of the plurality of outlets is provided with an opening / closing structure for opening and closing the outlet, and the control board controls the opening / closing structure based on the detection results of the plurality of temperature sensors. [Explanation of symbols]

[0095] 1 Rotating electric unit 2 Rotating electric machines 3 Power conversion device 5 Control board 7 Rotation detection unit 22 Temperature sensor 35 Rotation axis 35a Tip 36 Rotation detection target 58 Housing cover 60 Airflow generating structure 61 Flat fan 61a, 61b Flat blade 62 Oblique fan 62a oblique blade 63 Cylindrical cover 64 Air guide cover 64a spout 68 Opening and closing structure O axis center Z axis direction

Claims

1. a rotating electric machine having a rotating shaft; a power conversion device including: a control board arranged alongside the rotating electric machine in an axial direction along an axis of the rotating shaft and controlling the rotating electric machine; and a housing cover accommodating the control board; Equipped with an airflow generating structure that generates an airflow by utilizing the rotational movement of the rotation shaft is provided inside the housing cover; a tip end of the rotation shaft extends to an internal space of the housing cover, The airflow generating structure is fixed to the tip end of the rotating shaft. Rotating electric unit.

2. the power conversion device includes an inverter housed in the housing cover and a cooling structure that cools the inverter, The rotating electrical unit according to claim 1 , wherein the cooling structure is provided on the opposite side of the tip of the rotating shaft across the control board in the axial direction, and has a cooling surface that contacts the inverter.

3. the rotating electric machine has a rotation detection target attached to a tip end of the rotating shaft, the power conversion device includes a rotation detection unit that is provided opposite to the rotation detection target in the axial direction and detects rotation of the rotation detection target, The rotating electrical unit according to claim 1 , wherein the airflow generating structure includes the rotation detection target.

4. The rotating electrical machine unit according to claim 3 , wherein the airflow generating structure comprises a flat fan having a plurality of flat blades attached to the rotation detection target.

5. 5. The rotating electric unit according to claim 4, wherein each of the plurality of flat blades has an opposing surface facing the rotation detection unit in the axial direction, and the distance in the axial direction between the rotation detection unit and the opposing surface is configured to change circumferentially.

6. 3. The rotating electrical unit according to claim 1, wherein the airflow generating structure comprises an oblique fan having a plurality of oblique blades attached to an outer peripheral surface of the tip of the rotating shaft.

7. The rotating electrical unit according to claim 6 , wherein the airflow generating structure further comprises a cylindrical cover provided so as to surround the oblique fan.

8. the airflow generating structure further includes a wind guide cover provided to cover the flat fan, 5. The rotating electrical machine unit according to claim 4, wherein the air guide cover is provided with an outlet through which the airflow generated by the flat fan is ejected.

9. the power conversion device includes a plurality of temperature sensors for detecting a temperature inside the housing cover, The rotating electric unit according to claim 8, wherein the air guide cover is provided with a plurality of air outlets including the air outlet, each of the plurality of air outlets is provided with an opening / closing structure for opening and closing the air outlet, and the control board controls the opening / closing structure based on the detection results of the plurality of temperature sensors.

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