Cooling device for rotary electric machine

Abstract

This cooling device (100) for a rotary electric machine comprises: a rotary electric machine (30) that comprises a rotor (10) and a stator (20) disposed outward of the rotor (10) in the radial direction; a supply unit (40) that is formed in at least the rotor (30) and that supplies a cooling medium (R) to a flow path (F) through which the cooling medium (R) flows; and a control unit (50) that controls the flow rate of the cooling medium (R) in the flow path (F), wherein the control unit (50), in accordance with the rotational speed of the rotary electric machine (30), performs adjustment control for adjusting the flow rate of the cooling medium (R) in the flow path (F) such that the inside of the flow path (F) is in state of being filled with liquid by the cooling medium (R).

Description

Cooling device for rotating electrical machines

[0001] The present disclosure relates to a cooling device for a rotating electrical machine.

[0002] In rotating electric machines such as high-power motors for vehicles, the rotor magnet, stator coil, or their iron core, etc., heats up due to copper loss, iron loss, etc. that occurs within the rotating electric machine, resulting in high temperatures. In order to suppress performance degradation, reliability degradation, etc. that are caused by demagnetization of the rotor magnet due to high temperatures in such rotating electric machines, cooling devices for rotating electric machines as magnet oil cooling structures for motors have been disclosed in the past, such as the following.

[0003] That is, a magnet oil cooling structure of a motor as a cooling device for a conventional rotating electric machine includes an oil reservoir formed inside the rotor shaft and supplied with oil from the outside, a plurality of first oil passages extending radially from the oil reservoir to a plurality of cooling oil holes formed inside the rotor core radially inside the plurality of magnets, a plurality of second oil passages extending along the axial direction inside each of the magnets and from the cooling oil holes to the axial end of the rotor core, a pair of circular end plates attached to both ends of the rotor core, a third oil passage formed inside the end plates and having an axial portion connected to the axial end of each of the second oil passages and extending in the axial direction, and a discharge portion extending radially outward from the axial outer end of the axial portion and opening at the end of the end plate, and an angle reduction member arranged in the third oil passage at a corner formed by the axial portion and the discharge portion, which reduces the angle between the axial portion and the discharge portion in an axial cross section including the third oil passage (see, for example, Patent Document 1).

[0004] Japanese Patent Application Laid-Open No. 2022-107336

[0005] In the magnet oil cooling structure of the above-mentioned conventional motor, the amount of oil supplied from the oil reservoir of the rotor shaft to the second oil passage via the first oil passage depends on the rotational speed of the motor, so when the rotational speed of the motor is low, the amount of oil that reaches the third oil passage from the second oil passage is small, and the amount of oil that passes through the throttle portion of the third oil passage and is discharged to the outside is suppressed. As a result, each second oil passage is filled with a sufficient amount of oil, ensuring the cooling performance of the motor.

[0006] However, in such a magnet oil-cooled structure for a motor, due to centrifugal force, the coolant flows along the inner wall of the passage opposite the direction of rotation, while gas flows radially inward along the inner wall of the passage in the direction of rotation. As a result, gas may flow back from the opening of the third oil passage through the second oil passage to the passage in the shaft, causing the coolant in the passage in the rotor to become a gas-liquid two-phase flow containing gas. When the coolant in the passage becomes a gas-liquid two-phase flow, the pressure loss of the coolant increases, the flow rate decreases, and cooling performance deteriorates. The present disclosure discloses a technology for solving the above-mentioned problems and aims to provide a cooling device for a rotating electric machine that ensures high cooling performance.

[0007] The cooling device for a rotating electric machine disclosed herein is a cooling device for a rotating electric machine comprising: a rotating electric machine having a rotor and a stator arranged radially outside the rotor; a supply unit that supplies the cooling medium to a flow path formed in at least the rotor through which the cooling medium flows; and a control unit that controls the flow rate of the cooling medium in the flow path, wherein the control unit performs adjustment control to adjust the flow rate of the cooling medium in the flow path so that the flow path is filled with the cooling medium according to the rotation speed of the rotating electric machine.

[0008] According to the cooling device for a rotating electrical machine of the present disclosure, a cooling device for a rotating electrical machine that ensures high cooling performance can be obtained.

[0009] FIG. 4A is a block diagram showing a schematic configuration of the cooling device for a rotating electric machine according to embodiment 1. FIG. 4B is a conceptual diagram showing another example of the connection configuration of the flow paths F in the cooling device for a rotating electric machine according to embodiment 1. FIG. 4C is a conceptual diagram showing another example of the connection configuration of the flow paths F in the cooling device for a rotating electric machine according to embodiment 1. FIG. 4D is a conceptual diagram showing another example of the connection configuration of the flow paths F in the cooling device for a rotating electric machine according to embodiment 1. FIG. 4C is a conceptual diagram showing another example of the connection configuration of the flow paths F in the cooling device for a rotating electric machine according to embodiment 1. FIG. 4D is a conceptual diagram showing another example of the connection configuration of the flow paths F in the cooling device for a rotating electric machine according to embodiment 1. FIG. 4D is a diagram showing a hardware configuration of a control unit according to embodiment 1.

[0010] 1 is a cross-sectional view showing a schematic configuration of a cooling device 100 for a rotating electric machine according to embodiment 1. The cooling device 100 for a rotating electric machine according to this embodiment (hereinafter referred to as cooling device 100 as appropriate) includes a rotating electric machine 30, a supply unit 40 that supplies a cooling medium R to the rotating electric machine 30, and a control unit 50 that controls the flow rate of the cooling medium R, and cools the rotating electric machine 30 with the cooling medium R.

[0011] 1, the hatched areas with diagonal lines slanting upward to the right are areas through which the cooling medium R flows. In addition, the directions in the annular rotating electric machine 30 will be referred to as the circumferential direction S, the radial direction X, and the axial direction Y. In addition, in FIG. 1, the direction perpendicular to the axial direction Y of the cylindrical rotating electric machine 30 when the rotating electric machine 30 is disposed so that the axial direction Y of the rotating electric machine 30 is aligned with the horizontal direction is shown as the vertical direction Z.

[0012] First, a description will be given of the configuration of the rotating electric machine 30. The rotating electric machine 30 is housed in a housing 3 and includes a rotor 10 and a stator 20 disposed concentrically with the rotor 10 via a gap G set outside the rotor 10 in the radial direction X.

[0013] The rotor 10 is fixed to a rotating shaft 1 that is rotatably supported by bearings 2 that are fixed to a housing 3. The rotor 10 also has magnets 5 embedded in a portion that is radially outward of the rotating shaft 1 in the X direction. In this embodiment, the rotating shaft 1 is also a component of the rotor 10. The stator 20 has an iron core 20SC and a coil 20C attached to the iron core 20SC.

[0014] The supply unit 40 includes a cooler 41 and a pump 42, and is connected to the rotating electric machine 30 via flow paths F1 and F2 (F2A and F2B). The cooler 41 cools the cooling medium R discharged from the rotating electric machine 30 via flow path F1. The pump 42 supplies the cooling medium R cooled by the cooler 41 to the rotating electric machine 30 via flow path F2. An inverter 60 that drives the rotating electric machine 30 is provided on flow path F2, and the cooling medium R cools the inverter 60 before being supplied to the rotating electric machine 30. Downstream of the inverter 60, the flow path F2 branches into a flow path F2A connected to the housing 3 of the rotating electric machine 30 and a flow path F2B connected to the rotating shaft 1 of the rotating electric machine 30.

[0015] The following describes the flow path of the cooling medium R within the rotating electric machine 30. As described above, the rotor 10 and the stator 20 that constitute the rotating electric machine 30 generate heat, and therefore may be referred to as heat-generating parts in the following description. The inverter 60 may also be treated as a heat-generating part. Other heat-generating parts of the rotating electric machine 30 other than the rotor 10 and the stator 20 may also be treated as heat-generating parts.

[0016] The control unit 50 controls the pump 42 to adjust the flow rate of the cooling medium R supplied to the rotating electric machine 100. The cooling medium R output from the pump 42 and having cooled the inverter 60 is supplied to a flow path F3 provided in the housing 3 and a flow path F5 provided in the rotating shaft 1 via flow paths F2A and F2B. The flow path F3 is formed in the housing 3 so as to extend in the axial direction Y around the entire circumference of the housing 3 in the circumferential direction S. The cooling medium R supplied into the flow path F3 of the housing 3 is supplied radially to the outer periphery of the stator 20 via discharge ports F3O provided at set intervals in the axial direction Y and the circumferential direction S, respectively.

[0017] The cooling medium R supplied to the stator 20 flows downward in the vertical direction Z while cooling the coils 20C along the outer periphery of the stator 20, and flows into the flow path F4 of the rotor 10 through an opening F4O of the flow path F4 provided in the rotor 10. The cooling medium R supplied to the stator 20 is also supplied into the gap G between the stator 20 and the rotor 10, but the cooling medium R in this gap G is not shown in FIG.

[0018] Flow path F4 of rotor 10 extends from the axial center of rotating shaft 1 outward in radial direction X so as to be able to cool the entire area of ​​both end portions of rotor 10 in axial direction Y. This flow path F4 is connected to flow path F6, which is formed in rotor 10 to extend in axial direction Y along magnet 5, and to flow path F5, which is formed in rotating shaft 1. In this way, cooling medium R supplied to flow path F4 in rotor 10 also flows into these flow paths F5 and F6, cooling magnet 5 and rotating shaft 1. Cooling medium R from flow path F2B described above is also supplied to flow path F5 in rotating shaft 1. Hereinafter, when it is not necessary to distinguish between the above-mentioned flow paths, they will be simply referred to as flow path F.

[0019] In this way, the cooling medium R supplied into the flow path F cools each component of the rotating electric machine 30, such as the rotor 10, stator 20, and rotating shaft 1, which are heat-generating parts. After cooling each heat-generating part, the cooling medium R is stored in the lower part of the housing 3 through an opening F4O located below in the vertical direction Z, and is discharged to the outside of the rotating electric machine 30 through an opening F7O. The discharged cooling medium R is returned to the cooler 41 through the flow path F1, cooled by the cooler 41, and then supplied to the rotating electric machine 30 again.

[0020] Hereinafter, a description will be given of the flow rate control by the control unit 50, which is a main part of this embodiment. As will be described below, the control unit 50 of this embodiment performs adjustment control to adjust the flow rate of the cooling medium R in the flow path F in accordance with the rotation speed of the rotating electrical machine 30 during operation so that the inside of the flow path F is filled with the cooling medium R.

[0021] 2 is a diagram showing state diagram data M held by the control unit 50 according to embodiment 1. The state diagram data M shows the state of the cooling medium R in the flow path F according to the relationship between the rotation speed of the rotor 10 and the flow rate of the cooling medium R in the flow path F.

[0022] As a result of extensive research by the inventors, it was found that the state of the cooling medium R in the flow path F depends on the rotation speed [rpm] of the rotor 10 and the flow rate [L / min] supplied to the flow path F. Specifically, as shown in Fig. 2, it was found that the cooling medium R exists in a first region A1 in a single-phase state of only liquid, a third region A3 in a two-phase state of gas-liquid mixed with gas, and a second region A2 between the first region A1 and the third region A3 in either a single-phase state or a two-phase state of gas-liquid.

[0023] Furthermore, it was found that the second region A2, which is in either a single-phase state or a two-phase state, changes its state to either a single-phase state or a two-phase state depending on the direction of increase / decrease in the flow rate, the jerk of the rotation speed, etc.

[0024] The control unit 50 of this embodiment is provided with phase diagram data M that defines a first region A1 where the cooling medium R is in a single-phase state, a third region A3 where the cooling medium R is in a two-phase gas-liquid state, and a second region A2 where the cooling medium R is in either a single-phase state or a two-phase gas-liquid state. Based on this phase diagram data M, the control unit 50 adjusts the flow rate of the cooling medium R in the flow path F in accordance with the rotation speed of the rotor 10 so that the cooling medium R in the flow path F is in a single-phase state. This achieves adjustment control so that the flow path F is filled with the cooling medium R without being in a two-phase gas-liquid state.

[0025] The operation of the control unit 50 will be described in detail. For example, when the rotation speed of the rotor 10 and the flow rate of the cooling medium R in the flow path F are at the values ​​indicated by P1 in the second region A2 shown in FIG. 2, the state of the cooling medium R is estimated to be either a single-phase state or a two-phase state. In this case, the control unit 50 performs adjustment control to control the pump 42 by increasing the flow rate of the cooling medium R in the flow path F, as indicated by arrow D1, so that the flow rate reaches the value indicated by P2 in the first region A1. This causes the rotation speed of the rotor 10 and the flow rate of the cooling medium R in the flow path F to reach the values ​​specified in the first region A1, thereby stabilizing the state of the cooling medium R in the flow path F to a single-phase state. In this way, the flow path F is stably filled with liquid.

[0026] Furthermore, as a result of extensive research by the inventors, it was found that when the increase or decrease in the rotation speed of the rotor 10 is within a set first range, the state of the cooling medium R in the flow path F is maintained in a single layer state even if the flow rate of the cooling medium R is reduced from the flow rate specified in the first region A1 to the flow rate specified in the second region A2.

[0027] For example, when the rotation speed of the rotor 10 and the flow rate of the cooling medium R in the flow path F are at a value P3 in the first region A1 shown in FIG. 2 , the cooling medium R is in a single-phase state. Here, when the increase or decrease in the rotation speed of the rotor 10 is within a set first range, the flow rate of the cooling medium R in the flow path F is reduced as indicated by arrow D2, and the pump 42 is controlled to change the flow rate from the first region A1 to a value P4 in the second region A2. When the flow rate is reduced in this manner, the cooling medium R in the flow path F remains in a single-phase state even when the rotation speed and flow rate are within the second region A2. By performing such adjustment control, the flow rate of the supplied cooling medium R can be reduced while maintaining the single-phase state of the cooling medium R. This reduces power consumption in the pump 42 and the cooler 41, enabling higher efficiency.

[0028] Furthermore, as described below, it is also possible to combine control of increasing the flow rate of the cooling medium R, as indicated by arrow D1, with control of decreasing the flow rate of the cooling medium R, as indicated by arrow D2. For example, when the rotation speed of the rotor 10 and the flow rate of the cooling medium R in the flow path F are at a value P1 in the second region A2, it is estimated that the cooling medium R is in either a single-phase state or a two-phase state. In this case, the control unit 50 first increases the flow rate of the cooling medium R in the flow path F, as indicated by arrow D1, and then performs adjustment control to control the pump 42 so that the flow rate reaches the value P2 in the first region A1. This allows the cooling medium R in the flow path F to be stabilized in a single-phase state. Thereafter, when the increase or decrease in the rotation speed of the rotor 10 is within a set first range, adjustment control is performed to decrease the flow rate of the cooling medium R in the flow path F, as indicated by arrow D2. This allows the cooling medium R to be in a single-phase state or a two-phase state even when it is unclear whether the cooling medium R is in a single-phase state or a two-phase state, thereby reducing the flow rate of the cooling medium R supplied.

[0029] In addition, the above-described adjustment control for filling the flow path F with the cooling medium R may be performed according to the detection result of a detection unit, for example, when a detection unit is provided for detecting the gas-liquid two-phase state of the cooling medium R. Furthermore, the first range that defines the amount of increase or decrease in the rotation speed of the rotor 10 may be derived in advance by experiment or the like, or may be derived by simulation or the like.

[0030] Here, the state diagram data M of the control unit 50 may be defined according to the inner diameter of the flow path F, as will be described below. Fig. 3 is a diagram showing a state in which the state diagram data M possessed by the control unit 50 according to the first embodiment is defined according to the inner diameter of the flow path F. In this state diagram data M, a first boundary B1 which is the boundary between the first region A1 and the second region A2, and a second boundary B2 which is the boundary between the second region A2 and the third region A3 are each defined according to the inner diameter of the flow path F.

[0031] For example, when the first boundary B1 is defined as B1-1 when the inner diameter of the flow path F is 27.5 mm, the slope of the first boundary B1-2 in the flow path F having an inner diameter three times larger than this boundary increases as shown in Figure 3. Also, when the first boundary B1 is defined as B1-1 when the inner diameter of the flow path F is 27.5 mm, the slope of the first boundary B1-3 in the flow path F having an inner diameter 0.25 times larger than this boundary decreases as shown in Figure 3.

[0032] For example, when the second boundary B2 is defined as B2-1 when the inner diameter of the flow path F is 27.5 mm, the slope of the second boundary B2-2 in the flow path F having an inner diameter three times larger than this increases as shown in Figure 3. When the second boundary B2 is defined as B2-1 when the inner diameter of the flow path F is 27.5 mm, the slope of the second boundary B2-3 in the flow path F having an inner diameter 0.25 times larger than this decreases as shown in Figure 3.

[0033] Furthermore, the state diagram data M of the control unit 50 may be defined according to the temperature of the cooling medium R. In this case, as will be described below, the state diagram data M can be defined based on the connection configuration of the flow paths F. FIG. 4A is a conceptual diagram showing an example of the connection configuration of the flow paths F in the cooling device 100 for a rotating electric machine according to the first embodiment. FIG. 4B is a conceptual diagram showing another example of the connection configuration of the flow paths F in the cooling device 100 for a rotating electric machine according to the first embodiment. FIG. 4C is a conceptual diagram showing another example of the connection configuration of the flow paths F in the cooling device 100 for a rotating electric machine according to the first embodiment. FIG. 4D is a conceptual diagram showing another example of the connection configuration of the flow paths F in the cooling device 100 for a rotating electric machine according to the first embodiment.

[0034] 4A , the flow path F is configured to serially cool each component of the rotating electric machine 30, including the stator 20 and the rotor 10, downstream of the inverter 60. In this case, in the state diagram data M, a first boundary B1, which is the boundary between the first region A1 and the second region A2, and a second boundary B2, which is the boundary between the second region A2 and the third region A3, are defined taking into account the temperature rise of the cooling medium R resulting from cooling each heat-generating component.

[0035] 4B , the flow path F is configured to branch downstream of the inverter 60 and be parallel between the inverter 60 and the rotor 10 and stator 20, which are components of the rotating electric machine 30. In this case, in the state diagram data M, a first boundary B1, which is the boundary between the first region A1 and the second region A2, and a second boundary B2, which is the boundary between the second region A2 and the third region A3, are each defined taking into account the temperature rise of the cooling medium R caused by cooling the inverter 60.

[0036] 4C and 4D , the flow path F is configured to branch downstream of the pump 42 and be parallel between the pump 42 and each heat-generating portion. In this case, in the state diagram data M, a first boundary B1 between the first region A1 and the second region A2 and a second boundary B2 between the second region A2 and the third region A3 are defined based on the temperature of the cooling medium R downstream of the pump 42.

[0037] As described above, by defining the phase diagram data M that takes into account the temperature of the cooling medium R based on the structure of the flow path F of the cooling device 100, it is possible to perform adjustment control to fill the flow path F with the cooling medium R with precision.

[0038] The detailed configuration of the rotating electric machine 30 is not limited as long as the flow path F is provided at least in the rotor 10 and can cool at least the rotating electric machine 30 including the rotor 10. Therefore, the number of parallel flow paths connected to each heat-generating component may be increased, or each flow path may be configured in series. Furthermore, the adjustment control for filling the flow path F with the cooling medium R does not control the cooling medium R in the gap G between the rotor 10 and the stator 20. The cooling medium R flowing through the gap G is assumed to have its gas / coolant mixture ratio separately controlled, taking into account drag loss of the rotor 10. Furthermore, the control unit 40 may also control the inverter 60. In this way, the state diagram data M may be defined according to the control state of the inverter 60, i.e., the heat generation state of the inverter.

[0039] The hardware configuration of the control unit 50 will be described below. FIG. 5 is a diagram showing the hardware configuration of the control unit 50 as a control device according to the first embodiment. The control unit 50 as a control device includes a processor 51 and a storage device 52, as shown in FIG. 5 as an example of hardware. The storage device 52 includes a volatile storage device such as a random access memory and a non-volatile auxiliary storage device such as a flash memory, both not shown. Alternatively, a hard disk auxiliary storage device may be provided instead of the flash memory. The processor 51 executes a program input from the storage device 52. In this case, the program is input to the processor 51 from the auxiliary storage device via the volatile storage device. The processor 51 may output data such as calculation results to the volatile storage device of the storage device 52, or may store the data in the auxiliary storage device via the volatile storage device.

[0040] The cooling device for a rotating electric machine of this embodiment configured as described above is a cooling device for a rotating electric machine comprising a rotating electric machine having a rotor and a stator arranged radially outside the rotor, a supply unit that supplies the cooling medium to a flow path formed in at least the rotor through which the cooling medium flows, and a control unit that controls the flow rate of the cooling medium in the flow path, wherein the control unit performs adjustment control to adjust the flow rate of the cooling medium in the flow path so that the flow path is filled with the cooling medium according to the rotation speed of the rotating electric machine.

[0041] This prevents gas from flowing in while the rotating electrical machine is in operation, keeps the flow passages filled with the cooling medium, and prevents a partial decrease in flow rate. This prevents an increase in pressure loss of the cooling medium in the flow passages, which causes an imbalance in the discharge of the cooling medium and results in a partial decrease in cooling performance, thereby providing a cooling device for a rotating electrical machine that ensures high cooling performance.

[0042] Furthermore, in the cooling device for a rotating electric machine of this embodiment configured as described above, the control unit has phase diagram data that shows the state of the cooling medium in the flow path according to the relationship between the rotation speed of the rotor and the flow rate of the cooling medium in the flow path, and the phase diagram data defines a first region in which the state of the cooling medium is a single-phase state of liquid phase only, a third region in which the state of the cooling medium is a two-phase state of gas-liquid mixed with gas, and a second region existing between the first region and the third region in which the state is either the single-phase state or the two-phase state of gas-liquid, and in the adjustment control, the control unit controls the flow rate of the cooling medium in the flow path according to the rotation speed of the rotor based on the phase diagram data so that the cooling medium is in the single-phase state.

[0043] In this way, by adjusting the flow rate based on the phase diagram data so that the cooling medium in the flow passage is in a single-phase state, the flow passage can be filled with the cooling medium, thereby ensuring high cooling performance of the cooling device for the rotating electrical machine.

[0044] Furthermore, in the cooling device for a rotating electric machine of this embodiment configured as described above, the control unit controls the flow rate of the cooling medium according to the rotation speed of the rotor to a flow rate specified within the first region during the adjustment control.

[0045] This allows the flow passage to be stably filled with the cooling medium, ensuring high cooling performance of the cooling device for the rotating electrical machine regardless of the load on the rotating electrical machine.

[0046] Furthermore, in the cooling device for a rotating electric machine of this embodiment configured as described above, in the adjustment control, when the rotation speed of the rotor and the flow rate of the cooling medium in the flow path are values ​​specified within the first region and the increase / decrease in the rotation speed of the rotor is within a set first range, the control unit adjusts the flow rate of the cooling medium in the flow path to a flow rate specified within the second region.

[0047] This allows the flow rate of the cooling medium to be reduced while keeping the flow path filled with the liquid, thereby enabling lower power consumption and higher efficiency.

[0048] Although exemplary embodiments are described in the present disclosure, the various features, aspects, and functions described in the embodiments are not limited to the application of a particular embodiment, but may be applied to the embodiments alone or in various combinations. Therefore, countless variations not illustrated are anticipated within the scope of the technology disclosed in this specification. For example, variations in, addition to, or omission of at least one component are included.

[0049] 10 rotor (heat generating portion, component), 20 stator (heat generating portion, component), G gap, 30 rotating electric machine, F flow path, 40 supply unit, 50 control unit, 60 inverter (heat generating portion), 100 cooling device for rotating electric machine, A1 first region, A2 second region, A3 third region, M phase diagram data.

Claims

1. A cooling device for a rotating electric machine comprising: a rotating electric machine having a rotor and a stator arranged radially outside the rotor; a supply unit that supplies a cooling medium to a flow path formed in at least the rotor through which the cooling medium flows; and a control unit that controls the flow rate of the cooling medium in the flow path, wherein the control unit performs adjustment control to adjust the flow rate of the cooling medium in the flow path so that the flow path is filled with the cooling medium according to the rotation speed of the rotating electric machine.

2. A cooling device for a rotating electric machine as described in claim 1, wherein the control unit has state diagram data that shows the state of the cooling medium in the flow path according to the relationship between the rotation speed of the rotor and the flow rate of the cooling medium in the flow path, and the state diagram data defines a first region in which the state of the cooling medium is a single-phase state of liquid only, a third region in which the state is a two-phase gas-liquid state in which gas is mixed, and a second region existing between the first region and the third region in which the state is either the single-phase state or the two-phase gas-liquid state, and the control unit, in the adjustment control, controls the flow rate of the cooling medium in the flow path according to the rotation speed of the rotor based on the state diagram data so that the cooling medium is in the single-phase state.

3. The cooling device for a rotating electric machine according to claim 2, wherein the control unit controls the flow rate of the cooling medium according to the rotation speed of the rotor to a flow rate defined within the first region during the adjustment control.

4. A cooling device for a rotating electric machine as described in claim 2, wherein, in the adjustment control, the control unit adjusts the flow rate of the cooling medium in the flow path to a flow rate specified in the second region when the rotation speed of the rotor and the flow rate of the cooling medium in the flow path are values ​​specified in the first region and the increase / decrease in the rotation speed of the rotor is within a set first range.

5. A cooling device for a rotating electric machine as described in claim 2, wherein, in the adjustment control, the control unit adjusts the flow rate of the cooling medium in the flow path to a value specified in the first region when the rotation speed of the rotor and the flow rate of the cooling medium in the flow path are values ​​specified in the second region, and then adjusts the flow rate of the cooling medium in the flow path to a flow rate specified in the second region when the increase or decrease in the rotation speed of the rotor is within a set first range.

6. A cooling device for a rotating electric machine described in any one of claims 2 to 5, wherein in the phase diagram data, a first boundary that is the boundary between the first region and the second region, and a second boundary that is the boundary between the second region and the third region are each defined according to the inner diameter of the flow path.

7. A cooling device for a rotating electric machine described in any one of claims 2 to 6, wherein in the phase diagram data, a first boundary that is the boundary between the first region and the second region and a second boundary that is the boundary between the second region and the third region are each defined according to the temperature of the cooling medium in the flow path.

8. A cooling device for a rotating electric machine as described in any one of claims 2 to 7, wherein the flow path through which the cooling medium flows is configured to supply the cooling medium via the supply unit to an inverter that drives the rotating electric machine as a heat-generating part, and to each component that constitutes the rotating electric machine, including the stator and the rotor as heat-generating parts, and the flow path is configured to branch downstream of the inverter and be parallel between the inverter and each component that constitutes the rotating electric machine, and in the state diagram data, a first boundary that is a boundary between the first region and the second region, and a second boundary that is a boundary between the second region and the third region, are each defined based on a temperature rise of the cooling medium caused by the inverter.

9. A cooling device for a rotating electric machine as described in any one of claims 2 to 7, wherein the flow path through which the cooling medium flows is configured to supply the cooling medium via the supply unit to each component of the rotating electric machine, including an inverter that drives the rotating electric machine as a heat-generating part, and the stator and rotor that are heat-generating parts, and the flow path is configured to branch downstream of the supply unit and be parallel between the supply unit and the heat-generating part, and in the state diagram data, a first boundary that is the boundary between the first region and the second region, and a second boundary that is the boundary between the second region and the third region, are each defined based on the temperature of the cooling medium in the flow path downstream of the supply unit.

10. A cooling device for a rotating electric machine as described in any one of claims 2 to 7, wherein the flow path through which the cooling medium flows is configured to supply the cooling medium via the supply unit to each component of the rotating electric machine, including an inverter that drives the rotating electric machine as a heat-generating part, and the stator and rotor that constitute the rotating electric machine as heat-generating parts, and the flow path is configured to cool each of the components in series downstream of the inverter, and in the state diagram data, a first boundary that is the boundary between the first region and the second region, and a second boundary that is the boundary between the second region and the third region, are respectively defined based on the temperature rise of the cooling medium in each of the heat-generating parts.

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