JP2018170923A - Cooling system of rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooling system of a rotary electric machine which can suppress reduction in cooling performance and suppress noise.SOLUTION: A motor cooling system 100 includes: a rotor 22 in which a plurality of axially extending holes 77 are formed along the circumferential direction; a motor 23 having a stator 21; a refrigerant supply unit 12a for supplying refrigerant to the plurality of holes 77 through an output shaft 24; and a control device 12b for controlling the refrigerant supply unit 12a. The control device 12b sets a supply amount of the refrigerant to be supplied to the plurality of holes 77 of the rotor 22 so that a supply amount of the refrigerant increases as rotation speed increases on the basis of a rotation number of the rotor 22.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a cooling system for a rotating electrical machine.

  In recent years, vehicles equipped with electric motors (motors) for driving vehicles such as fuel cell vehicles, hybrid vehicles, and electric vehicles have been developed one after another. As an electric motor, a rotor (rotor) that is rotatably supported around an axis line, a rotor (rotor) in which a permanent magnet is disposed, and a stator (stator) that is disposed to face the periphery of the rotor and in which a coil is disposed. Is generally provided (see, for example, Patent Document 1).

By the way, a cooling system for a rotating electrical machine that supplies a cooling medium to the rotor has been proposed for the purpose of suppressing a temperature increase of the magnet of the rotor due to an increase in the rotational speed of the rotor when the motor is driven.
For example, in Patent Literature 2, a rotor having a plurality of holes extending in the axial direction of the output shaft is formed along the circumferential direction, and a cooling medium is supplied to the holes.

Japanese Patent No. 5261836 JP 2014-60857 A

  However, when the cooling medium is supplied to the holes of the rotor in which a plurality of holes extending in the axial direction of the output shaft are formed along the circumferential direction as in Patent Document 2, the cooling medium cannot move between the holes of the rotor. Therefore, an unbalance of the cooling medium amount (hereinafter referred to as rotor unbalance) occurs between the holes of the rotor. For example, in a constant amount of axial center lubrication (cooling) performed by motor magnet cooling, centrifugal force acting on an ATF (Automatic transmission fluid) that is a cooling medium according to the number of rotations of the rotor, There was a problem that the dynamic variation of the rotor deteriorated and the vibration and noise of the vehicle deteriorated.

  This invention is made | formed in view of such a situation, and provides the cooling system of the rotary electric machine which can make suppression of the fall of cooling performance and suppression of noise compatible.

In order to solve the above-described problems, a cooling system for a rotating electrical machine according to the present invention (for example, the motor cooling system 100 in the embodiment) has an axially extending hole (for example, the hole 77 in the embodiment) in the circumferential direction. A rotating electric machine (for example, the motor 23 in the embodiment) having a rotor (for example, the rotor 22 in the embodiment) formed along the rotor and a stator (for example, the stator 21 in the embodiment), and the rotor A refrigerant supply unit (for example, the refrigerant supply unit 12a in the embodiment) that supplies refrigerant to the plurality of holes through a shaft (for example, the output shaft 24 in the embodiment), and a control device (for example, implementation) that controls the refrigerant supply unit A control device 12b) according to the embodiment, wherein the control device is based on the number of rotations of the rotor. As the supply amount of the refrigerant as the number of rolling becomes higher increases, and sets the supply amount of refrigerant supplied to the plurality of holes of the rotor.
According to the present invention, the higher the rotor rotational speed, the greater the amount of heat generated while suppressing the deterioration of the rotor unbalance amount by adjusting the refrigerant supply amount to the rotor so as to increase the refrigerant supply amount to the rotor. On the high rotation side, the coolant supply amount can be increased to suppress a decrease in cooling performance.

The present invention is also the above-described cooling system for a rotating electrical machine, wherein the refrigerant supply unit adjusts the flow rate of the refrigerant flow path from the pump (for example, the pump 121 in the embodiment) to the rotor. A valve (for example, the valve 122 in the embodiment) and a temperature detector (for example, the temperature detector 123 in the embodiment) for detecting or estimating the temperature of the refrigerant, and the control device includes the temperature detector. The valve is controlled such that the flow rate of the refrigerant flow path to the rotor decreases with an increase in the refrigerant temperature detected or estimated by.
According to the present invention, as the rotor rotational speed increases, the refrigerant supply amount to the rotor is accurately adjusted so as to increase the refrigerant supply amount to the rotor, thereby accurately suppressing deterioration of the rotor unbalance amount. On the high rotation side where heat generation increases, the amount of refrigerant supplied can be increased to accurately suppress a decrease in cooling performance.

The present invention is the above-described cooling system for a rotating electrical machine, wherein the rotor is disposed at a rotor core (for example, the rotor core 22a in the embodiment) and an axial end of the rotor core. An end plate (for example, an end face plate 25 in the embodiment), and a plurality of communication grooves (for example, in the embodiment) that extend in the radial direction and communicate with the shaft and the plurality of holes. A groove 25a) is formed.
Since the end plate arranged at the end of the rotor core in the axial direction extends in the radial direction and has a plurality of communication grooves that connect the shaft and the plurality of holes, the control device has a high rotational speed. The amount of refrigerant supplied to the plurality of holes of the rotor can be set so that the amount of refrigerant supplied increases. Therefore, according to the present invention, as the rotor rotational speed increases, the refrigerant supply amount to the rotor is adjusted so as to increase the refrigerant supply amount to the rotor. On the higher rotation speed side, the refrigerant supply amount can be increased to prevent the cooling performance from decreasing.

  According to the present invention, the higher the rotor rotational speed, the greater the amount of heat generated while suppressing the deterioration of the rotor unbalance amount by adjusting the refrigerant supply amount to the rotor so as to increase the refrigerant supply amount to the rotor. On the high rotation side, the coolant supply amount can be increased to suppress a decrease in cooling performance. That is, it is possible to provide a cooling system for a rotating electrical machine that can achieve both suppression of a decrease in cooling performance and suppression of noise by changing the amount of shaft center oil supply according to the number of rotations of the rotor.

1 is a diagram showing a motor cooling system 100 including a schematic configuration cross-sectional view of a motor unit 10 according to an embodiment of the present invention. It is sectional drawing of the rotor 22 in the R direction of FIG. FIG. 5 is a diagram for explaining a problem when supplying a refrigerant to a rotor 22. It is a figure for demonstrating the operation | movement which sets the supply amount of the refrigerant | coolant of the control apparatus 12b at the time of supplying a refrigerant | coolant to the rotor 22. FIG. It is a flowchart which shows the operation example of the control apparatus 12b shown in FIG.

  A rotating electrical machine cooling system (hereinafter referred to as a “motor cooling system”) according to an embodiment of the present invention will be described below with reference to the drawings. In the present embodiment, description will be made using a vehicle electric motor (hereinafter referred to as “motor unit”) mounted on a vehicle. In the following description, the radial direction of the motor is defined as the R direction, the axial direction of the motor is defined as the Z direction, and the circumferential direction of the motor is defined as the θ direction. If necessary, the cylindrical coordinate system of these R, Z, and θ is defined. Use and explain. One side in the Z direction is the + Z side, and the other side is the -Z side. The outer peripheral side in the R direction is the + R side, and the inner peripheral side is the -R side.

FIG. 1 is a diagram showing a motor cooling system 100 including a schematic sectional view of a motor unit 10 according to an embodiment of the present invention.
As shown in FIG. 1, the motor cooling system 100 of this embodiment includes a motor unit 10, a mission housing 12 and a sensor housing 13.
In the motor unit 10 of this embodiment, a motor (rotating electrical machine) 23 including a stator (stator) 21 and a rotor 22 (rotor) is accommodated in the motor housing 11. A sensor housing 13 that houses a rotation sensor (not shown) that detects the number of rotations of the output shaft 24 of the motor 23 is fastened to the + Z side of the motor housing 11. The rotation sensor is a sensor that detects the number of rotations of the rotor called a so-called resolver.
A transmission housing 12 that houses a power transmission unit (not shown) such as a gear that transmits power from the output shaft 24 of the motor 23 is fastened to the −Z side of the motor housing 11. The output shaft 24 of the motor 23 is connected to the drive shaft of the vehicle via the power transmission unit of the motor unit 10. By rotating the drive shaft, the wheel connected to the drive shaft is rotated so that the vehicle can be moved.

Further, as shown in FIG. 1, the mission housing 12 includes a refrigerant supply unit 12a that supplies a cooling medium (refrigerant) that is ATF to the plurality of holes 77 through the output shaft 24, and a control device 12b that controls the refrigerant supply unit 12a. And. The refrigerant supply unit 12a includes a pump 121, a valve 122, and a temperature detector 123.
The pump 121 adjusts ATF, which is cooling oil supplied from the outside, by the valve 122 to supply the adjusted ATF to the cooling medium flow path 75 (refrigerant flow path). The pump 121 is, for example, an electric oil pump (EOP; Electric Oil Pump), and supplies a constant amount of ATF at a constant rotation. The ATF discharged from the pump 121 branches before the valve 122 and is supplied to the brake hydraulic circuit and the stator winding cooling.
The valve 122 adjusts the flow rate of the coolant flow path 75 from the pump 121 to the rotor 22.
The valve 122 is a kind of an electrically driven valve also called, for example, an electromagnetic valve or a solenoid valve, and opens and closes the valve (valve) by moving an iron piece called a plunger using the magnetic force of an electromagnet (solenoid). It has a mechanism and is used to control the opening and closing of a flow through a pipe that passes fluid (oil, water, etc.)

The temperature detector 123 detects or estimates the temperature of the refrigerant. Here, the temperature detector 123 may detect the temperature of the ATF supplied to the plurality of holes 77 with a temperature sensor, or may be adjusted by the valve 122 and supplied to the cooling medium flow path 75. The temperature may be detected by a temperature sensor. Further, the temperature detector 123 causes the detected coolant flow path 75 to be detected based on a previously obtained relationship between the temperature of the ATF supplied to the coolant flow path 75 and the temperature of the ATF supplied to the plurality of holes 77. The temperature of the ATF supplied to the plurality of holes 77 may be estimated from the temperature of the supplied ATF.
The control device 12b controls the valve 122 so that the flow rate of the coolant flow path 75 to the rotor 22 decreases as the ATF temperature (refrigerant temperature) detected or estimated by the temperature detector 123 increases. ).

(Motor housing)
The motor housing 11 is a member made of aluminum or the like, and is molded by die casting or the like. The motor housing 11 is formed in a substantially bottomed cylindrical shape that can accommodate the motor 23.
The + Z side of the motor housing 11 where the sensor housing 13 is fastened is closed by the wall portion 17 except for the through hole 31 through which the output shaft 24 is inserted. On the other hand, a substantially circular opening 15 for inserting the motor 23 is formed on the −Z side of the motor housing 11 where the transmission housing 12 is fastened. Further, a step portion 19 that is reduced in diameter from the −Z side toward the + Z side is formed on the inner peripheral surface 18 of the motor housing 11. A stator holder 30 for supporting and fixing the stator 21 is fastened to the step portion 19.

  A bearing 26 that rotatably supports one end of the output shaft 24 of the motor 23 is provided on the −Z side at the boundary between the motor housing 11 and the transmission housing 12, and the boundary between the motor housing 11 and the sensor housing 13 is provided. A bearing 27 that rotatably supports the other end of the output shaft 24 of the motor 23 is provided on the + Z side in the section.

(Output shaft)
FIG. 2 is a cross-sectional view of the rotor 22 in the R direction of FIG.
As shown in FIG. 2, the output shaft 24 is disposed substantially at the center of the rotor 22.
The output shaft 24 is a hollow, substantially cylindrical member made of stainless steel, iron, or the like, and is formed by forging, casting, machining, or the like. The interior of the output shaft 24 is hollow and serves as a cooling medium flow path 75 (refrigerant path). Thereby, since the piping for comprising a cooling flow path etc. inside a motor is unnecessary, the increase in the weight and cost of a motor can be suppressed. In addition, on the + Z side of the output shaft 24, there are a plurality of discharge holes 76 that open to the outer peripheral surface and communicate with the cooling medium flow path 75 inside the output shaft 24 (in the present embodiment, in the circumferential direction (θ direction) of the motor). 8 places every 45 degrees). ATF, which is a cooling medium, is supplied from a valve 122 in the above-described refrigerant supply unit 12a, which is a supply source shown in FIG. The cooling medium supplied from the supply source passes through the cooling medium flow path 75 and is discharged from the discharge hole 76 to the + R side by the centrifugal force generated by the rotation of the rotor. For example, lubricating oil is used as the cooling medium.
In the present embodiment, the discharge hole 76 is formed only on the + Z side of the output shaft 24, but it may be formed on the −Z side of the output shaft 24.

(Rotor)
In the present embodiment, the rotor 22 includes a rotor core (rotor core) 22a and an end face plate 25 (end plate).
A rotor core 22 a is attached to the outer peripheral surface of the output shaft 24.
The rotor 22 is a member made of a magnetic plate such as a substantially disc-shaped electromagnetic steel plate, and has a rotor core 22a formed by laminating a plurality of magnetic plates formed by pressing. At this time, a convex portion (dwelling) is formed on each magnetic plate by overlapping and caulking each magnetic plate. The dowels can be used to connect and fix the magnetic plates. In addition, you may laminate | stack by adhere | attaching each magnetic board.
A through hole 31 for inserting the output shaft 24 is formed in the rotor core 22a. The rotor core 22a is fixed to the output shaft 24 by press fitting. Therefore, the through hole 31 is formed to be slightly smaller than the outer diameter of the output shaft 24. As the rotor core 22a rotates about the axis, the output shaft 24 also rotates about the axis at the same time.
A plurality of (in this embodiment, eight) permanent magnets 29 are provided in the vicinity of the outer peripheral edge of the rotor core 22a along the θ direction so as to face the stator 21. Note that permanent magnets 29N having N poles magnetized on the outer peripheral side of the rotor core 22a and permanent magnets 29S having S poles magnetized on the outer peripheral side of the rotor core 22a are alternately arranged in the θ direction of the rotor core 22a. Yes.
In addition, a plurality of (in this embodiment, eight) holes 77 extending in the Z direction (axial direction) are formed in the vicinity of the inner peripheral edge of the rotor core 22a in the θ direction (circumferential direction).

(End plate)
Furthermore, end face plates 25 are attached to the outer peripheral surface of the output shaft 24, and are arranged on both end faces in the Z direction of the rotor core 22a. That is, the end face plate 25 is disposed at the end of the rotor core 22a in the Z direction (axial direction). The end face plate 25 is made of a nonmagnetic material such as stainless steel, and is formed by pressing, machining, or the like. The end face plate 25 is a substantially disk-shaped member having substantially the same shape as the rotor core 22a, and a through hole 31 through which the output shaft 24 is inserted is formed. The end face plate 25 is fixed to the output shaft 24 by press fitting together with the rotor core 22a. The outer diameter of the end face plate 25 is substantially the same as or slightly smaller than the rotor core 22a, and is formed so as to cover the permanent magnet 29 when viewed from the Z direction. Accordingly, the permanent magnet 29 is prevented from falling off the rotor core 22a while securing an air gap between the stator 21 and the rotor core 22a. Further, since the end face plate 25 is made of a non-magnetic material, even if the permanent magnet 29 is covered, the magnetic flux leakage is not increased.

In this embodiment, the groove part 25a is formed in the mating surface with the rotor core 22a in the end face plate 25 on the + Z side. The groove portion 25 a has a substantially rectangular shape when viewed from the R direction, and the depth and width of the groove portion 25 a are formed substantially the same as the diameter of the discharge hole 76. In addition, the groove portion 25a has a plurality of (a plurality of holes 77) communicating with the discharge holes 76 of the output shaft 24 and the plurality of holes 77 along the R direction (extending in the radial direction) from a position corresponding to the discharge holes 76 of the output shaft 24. In the present embodiment, eight communication grooves are formed. That is, the cooling medium discharged from the discharge hole 76 passes through the groove 25a and is discharged toward the plurality of holes 77 toward the + R side. Further, the cooling medium is discharged from the rotor 22 through the discharge hole 78 as shown in FIG.
In the present embodiment, the groove portion 25a is formed only on the + Z side end face plate 25 corresponding to the discharge hole 76 formed on the + Z side of the output shaft 24, but on the −Z side of the output shaft 24. In the case where the discharge hole is formed, a groove is also formed on the end face plate on the -Z side.

(Stator)
Returning to FIG. 1, the stator 21 of this embodiment includes a stator core 41 formed in an annular shape, and a coil 20 configured by winding a conductor wire around the stator core 41 via an insulator 50.

The content described above is the motor unit 10 in the motor cooling system 100 of the present embodiment. In the motor cooling system 100, a control device 12b that controls the refrigerant supply unit 12a will be described below.
FIG. 3 is a diagram for explaining a problem in supplying the refrigerant to the rotor 22. FIG. 3 is a graph in which the horizontal axis represents the number of revolutions of the motor [rpm] and the vertical axis represents the sound pressure [dB], and the primary sound CMAX of the motor P and the maximum amount of rotor unbalance among the motor P In the motor P, the primary sound CMIN with the smallest rotor unbalance amount is shown. Here, the primary sound CMAX is different from the flow rate of the refrigerant flowing into the plurality of holes 77, for example, when the flow rate of two of the eight holes 77 is large, that is, the refrigerant flowing into the plurality of holes 77. Represents the primary sound of the rotor 22 when the rotor unbalance amount is large. The primary sound CMIN is the primary sound of the rotor 22 when the flow rate of the refrigerant flowing into the plurality of holes 77 is substantially equal, that is, when the rotor unbalance amount of the refrigerant flowing into the plurality of holes 77 is small. Represents.
In this way, since the pump 121 (Electric Oil pump) supplies a constant amount of refrigerant to the plurality of holes 77 when the rotation is constant, as shown in the primary sound CMAX in FIG. The rotor unbalance amount of the refrigerant flowing into the plurality of holes 77 increases, and the primary sound CMAX varies and increases. That is, due to the centrifugal force acting on the ATF according to the rotational speed of the rotor, the variation of the rotor 22 is deteriorated (the rotor unbalance amount is increased), and the vibration and noise of the vehicle may be deteriorated.

Accordingly, the control device 12b sets the supply amount of the refrigerant to be supplied to the plurality of holes 77 of the rotor 22 so that the supply amount of the refrigerant increases as the rotation speed increases, based on the rotation speed of the rotor 22. As a result, even in a region where the number of revolutions is high, even if the amount of refrigerant supplied is relatively large, a larger centrifugal force acts, so that the refrigerant is easily distributed uniformly from the output shaft 24 to the plurality of holes 77, and the rotor Deterioration of the unbalance amount can be suppressed.
Further, the control device 12b sets the supply amount of the refrigerant supplied to the plurality of holes 77 of the rotor 22 based on the rotation number of the rotor 22 so that the supply amount of the refrigerant decreases as the rotation number decreases. As a result, since the centrifugal force is small in the region where the rotational speed is low, the refrigerant amount is likely to be biased due to gravity or the like. Therefore, the deterioration of the rotor unbalance amount is suppressed by relatively reducing the refrigerant supply amount. I can do it.
That is, the control device 12b can suppress the deterioration of the cooling performance by suppressing the deterioration of the rotor unbalance amount and increasing the refrigerant supply amount in the high rotation speed region where the heat generation is large.

FIG. 4 is a diagram for explaining an operation of setting the refrigerant supply amount of the control device 12 b when supplying the refrigerant to the rotor 22. FIG. 4 shows the amount of restriction of the valve 122 at each temperature in a graph in which the horizontal axis represents the number of rotations of the motor and the vertical axis represents the amount of restriction of the valve 122. Since ATF (oil), which is a refrigerant, decreases in viscosity as the temperature rises, the flow rate increases as the temperature rises even at a constant pressure. Therefore, as shown in FIG. 4, even if the oil temperature changes, the control device 12b adjusts the throttle amount of the valve 122 so that the inflow amount becomes constant at each motor rotation speed.
That is, the temperature detector 123 shown in FIG. 1 detects the oil temperature shown in FIG. 4, and the controller 12b increases the refrigerant flow to the rotor 22 as the refrigerant temperature detected or estimated by the temperature detector 123 increases. By controlling the valve 122 so that the flow rate decreases (increasing the amount of restriction), the valve 122 is controlled so that the flow rate of the refrigerant flow path to the rotor 22 increases as the refrigerant temperature decreases. By reducing the amount), the supply amount of the refrigerant supplied to the plurality of holes 77 of the rotor 22 can be set so that the supply amount of the refrigerant becomes a constant amount when the rotation speed is high.
On the other hand, the temperature detector 123 shown in FIG. 1 detects the oil temperature shown in FIG. 4, and the controller 12b increases the refrigerant flow to the rotor 22 as the refrigerant temperature detected or estimated by the temperature detector 123 increases. By controlling the valve 122 so that the flow rate decreases (increasing the amount of restriction), the valve 122 is controlled so that the flow rate of the refrigerant flow path to the rotor 22 increases as the refrigerant temperature decreases. By reducing the amount), the supply amount of the refrigerant supplied to the plurality of holes 77 of the rotor 22 can be set so that the supply amount of the refrigerant becomes a small constant amount when the rotational speed is low.

Therefore, the control device 12b has a memory for storing the throttle amount of the valve 122 at each temperature as a MAP (map) in a graph in which the horizontal axis shown in FIG. 4 is the motor rotation speed and the vertical axis is the throttle amount of the valve 122. Have. The amount of restriction of the valve 122 at each of these temperatures is determined in advance by a measurement experiment. That is, the control device 12b prepares a MAP for each ATF (oil temperature) temperature. Of course, when the MAP for each temperature of ATF (oil temperature) is not prepared, the deterioration of the rotor unbalance amount of the refrigerant (ATF) supplied to the output shaft 24 is prepared, and the MAP for each temperature of ATF (oil temperature) is prepared. In comparison with this, it is impossible to accurately control the deterioration of the rotor unbalance amount in which the influence of the temperature is reflected.
However, even in that case, it is possible to suppress the deterioration of the rotor unbalance amount by preparing a MAP that does not deteriorate the rotor unbalance amount according to the rotational speed. The MAP corresponding to the rotational speed in this case shows a change having a negative slope with respect to the motor rotational speed, similarly to the throttle amount of the valve 122 at each temperature shown in FIG. The throttle amount can be determined by, for example, an average value of the throttle amount of the valve 122 at each temperature obtained in advance by a measurement experiment.
In the present embodiment, assuming that the control device 12b prepares a MAP for each temperature of ATF (oil temperature), an operation example of the control device 12b will be described below.

FIG. 5 is a flowchart showing an operation example of the control device 12b shown in FIG. The control device 12b executes each process shown in FIG. 5 every time a predetermined time elapses.
First, the control device 12b acquires the rotor rotational speed (step ST1).
Specifically, the control device 12b acquires the rotation speed of the rotor detected by the rotation sensor in the sensor housing 13 from the rotation sensor.
Subsequently, the control device 12b acquires the refrigerant temperature (step ST2).
Specifically, the control device 12b acquires the temperature of the ATF supplied to the coolant flow path 75 detected or estimated by the temperature detector 123.

Subsequently, the control device 12b calculates the throttle amount of the valve from the rotor rotational speed and the refrigerant temperature (step ST3).
Specifically, the control device 12b refers to a memory that stores the throttle amount of the valve 122 at each temperature as a MAP (map), and the valve 122 corresponding to the rotor rotational speed and the refrigerant temperature acquired in Steps ST1 and ST2 above. The aperture amount is calculated.
Finally, the control device 12b adjusts the throttle amount of the valve (step ST4).
Specifically, the control device 12b determines that the flow rate of the coolant flow path 75 to the rotor 22 is calculated in step ST3 as the ATF temperature (refrigerant temperature) detected or estimated by the temperature detector 123 increases. The valve 122 is controlled so as to decrease by the amount. That is, the control device 12b sets the supply amount of the refrigerant supplied to the plurality of holes 77 of the rotor 22 based on the rotation number of the rotor 22 so that the supply amount of the refrigerant increases as the rotation number increases.

  As described above, the cooling system for a rotating electrical machine according to the present embodiment includes the motor 23 including the rotor 22 having the plurality of holes 77 extending in the axial direction along the circumferential direction, the stator 21, and the output shaft 24. The motor cooling system 100 includes a refrigerant supply unit 12a that supplies a refrigerant to the plurality of holes 77 through a control device 12b that controls the refrigerant supply unit 12a. Then, the control device 12b sets the supply amount of the refrigerant supplied to the plurality of holes 77 of the rotor 22 so that the supply amount of ATF (refrigerant) increases as the rotation speed increases based on the rotation speed of the rotor 22. To do.

  Thereby, the cooling system for the rotating electrical machine according to the present embodiment suppresses deterioration of the rotor imbalance amount, and increases the refrigerant supply amount in a high rotational speed region where heat generation is large, thereby suppressing deterioration in cooling performance. I can do it.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and includes modifications and the like without departing from the gist of the present invention. For example, in the above-described embodiment, the refrigerant supply unit 12a includes the pump 121 and the valve 122. The refrigerant supply unit 12a may have a configuration in which the hydraulic pressure or flow rate is controlled by the pump itself using a pump capable of controlling the hydraulic pressure, a pump capable of controlling the flow rate, or the like.

  DESCRIPTION OF SYMBOLS 10 ... Motor unit (electric motor), 12 ... Mission housing, 12a ... Refrigerant supply part, 12b ... Control apparatus, 20 ... Coil, 21 ... Stator, 22 ... Rotor, 22a ... Rotor core (rotor core), 23 ... Motor (rotation) 24) output shaft, 25 ... end face plate (end plate), 25a ... groove, 41 ... stator core, 75 ... cooling medium flow path, 76 ... discharge hole, 77 ... hole, 100 ... motor cooling system, 121 ... Pump 122 ... Valve 123 ... Temperature detector

Claims (3)

A rotating electrical machine having a rotor formed with a plurality of axially extending holes along the circumferential direction, and a stator;
A refrigerant supply unit that supplies refrigerant to the plurality of holes through the shaft of the rotor;
A control device for controlling the refrigerant supply unit;
In a rotating electrical machine cooling system comprising:
The control device includes:
The supply amount of the refrigerant supplied to the plurality of holes of the rotor is set based on the rotation number of the rotor so that the supply amount of the refrigerant increases as the rotation number increases. Cooling system for rotating electrical machines. The refrigerant supply unit is
A pump,
A valve for adjusting the flow rate of the refrigerant flow path from the pump to the rotor;
A temperature detector for detecting or estimating the temperature of the refrigerant;
With
2. The control device according to claim 1, wherein the control device controls the valve so that the flow rate of the refrigerant flow path to the rotor decreases as the refrigerant temperature detected or estimated by the temperature detector increases. The rotating electrical machine cooling system described. The rotor is
The rotor core,
An end plate disposed at an axial end of the rotor core;
With
3. The rotating electrical machine according to claim 1, wherein the end plate is formed with a plurality of communication grooves that extend in a radial direction so as to communicate the shaft and the plurality of holes. Cooling system.

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