JP7421967B2 - Rotating electrical machine unit - Google Patents

Description

The present invention relates to a rotating electrical machine unit mounted on an electric vehicle or the like.

BACKGROUND ART Conventionally, electric vehicles such as hybrid vehicles, battery-powered vehicles, and fuel cell vehicles have been equipped with rotating electric machines such as electric motors and generators. In recent years, rotating electric machines installed in electric vehicles have been increasing in torque and output. A rotating electric machine generates losses such as copper loss, iron loss, and mechanical loss when driven, and generates heat in accordance with these losses. Therefore, the higher the torque and the higher the output, the more the amount of heat generated increases. If the rotating electric machine becomes excessively high temperature due to heat generation, permanent magnets may be demagnetized, resulting in a decrease in output performance.

Therefore, rotating electric machine units are required to further improve their cooling performance. A shaft center cooling structure is known as a cooling structure for a rotating electric machine unit. For example, in Patent Document 1, a refrigerant flow path extending in the axial direction is provided inside a rotor shaft, and the refrigerant supplied to the refrigerant flow path inside the rotor shaft is supplied to a rotor and a stator of a rotating electric machine. , a rotating electrical machine unit having an axial cooling structure for cooling a rotor and a stator of a rotating electrical machine is disclosed.

JP 2019-110695 Publication

However, in the rotating electrical machine unit of Patent Document 1, refrigerant is always supplied to the rotor and stator of the rotating electrical machine from the refrigerant flow path inside the rotor shaft, and a part of the refrigerant supplied from the refrigerant flow path inside the rotor shaft is It flows between the rotor and stator. In the rotating electric machine unit of Patent Document 1, even when the refrigerant does not need to warm up or when the rotating electric machine is at a low temperature and does not require cooling, the refrigerant flows between the rotor and the stator, so there is no need to warm up the refrigerant. When the rotary electric machine is at a low temperature and does not require cooling, a problem has been that the output efficiency of the rotary electric machine decreases due to the viscous resistance of the refrigerant flowing between the rotor and the stator.

The present invention provides a rotating electrical machine unit that can suppress a decrease in the output efficiency of the rotating electrical machine without reducing the cooling efficiency of the rotating electrical machine.

The present invention
A rotating electric machine having a rotor and a stator;
a rotor shaft that is rotatably connected to the rotor and is provided with a refrigerant flow path through which refrigerant flows;
a refrigerant supply device that supplies the refrigerant to the refrigerant flow path,
A rotating electrical machine unit in which the refrigerant passing through the refrigerant flow path is supplied to the rotor and the stator to cool the rotating electrical machine,
The refrigerant supply device includes:
a switching unit that switches between a shaft cooling implementation state in which the refrigerant is supplied to the refrigerant flow path and a shaft cooling stop state in which the refrigerant is not supplied to the refrigerant flow path;
a control section that controls the switching section;
The control unit includes:
comprising a refrigerant temperature calculation unit that calculates a refrigerant temperature that is the temperature of the refrigerant,
When the refrigerant temperature calculated by the refrigerant temperature calculation unit is within a predetermined refrigerant temperature range, controlling the switching unit so that the shaft center cooling is stopped;
The predetermined refrigerant temperature range is a temperature range that is equal to or higher than the first predetermined refrigerant temperature and equal to or lower than the second predetermined refrigerant temperature, which is higher than the first predetermined refrigerant temperature .

According to the present invention, when the refrigerant temperature calculated by the refrigerant temperature calculation unit is within the predetermined refrigerant temperature range, the control unit enters the shaft center cooling stop state in which refrigerant is not supplied to the refrigerant flow path of the rotor shaft. Since the switching unit is controlled in this manner, the amount of refrigerant flowing between the rotor and the stator is reduced, and a decrease in the output efficiency of the rotating electric machine can be suppressed. Furthermore, it is possible to set the predetermined refrigerant temperature range to a temperature range in which the cooling efficiency of the rotating electric machine does not decrease even if the refrigerant is not supplied to the coolant flow path of the rotor shaft, so there is no need to reduce the cooling efficiency of the rotating electric machine. , it is possible to suppress a decrease in the output efficiency of the rotating electric machine.

1 is a schematic diagram of a rotating electric machine unit according to an embodiment of the present invention. FIG. 2 is a cross-sectional perspective view of the vicinity of the rotating electrical machine showing the flow of refrigerant in FIG. 1. FIG. 2 is a flowchart for controlling a switching section in a control section of the refrigerant supply device of FIG. 1. FIG.

EMBODIMENT OF THE INVENTION Hereinafter, one embodiment of the rotating electric machine unit 1 of this invention is described based on an accompanying drawing.

<Rotating electrical machine unit>
As shown in FIGS. 1 and 2, the rotating electrical machine unit 1 of this embodiment includes a rotating electrical machine 10 having a rotor 20 and a stator 30, a rotor shaft 40, and a refrigerant supply device 60. The rotating electric machine 10 and the rotor shaft 40 are housed in a case 80.

Note that in this specification and the like, the terms axial direction, radial direction, and circumferential direction refer to directions based on the rotational axis of the rotating electrical machine 10. Moreover, the axially inner side refers to the center side of the rotating electrical machine 10 in the axial direction, and the axially outer side refers to the side away from the center of the rotating electrical machine 10 in the axial direction.

The rotor shaft 40 is a hollow shaft rotatably connected to the rotor 20, and is provided with a refrigerant passage 51 through which refrigerant flows. The refrigerant flow path 51 extends in the axial direction inside the rotor shaft 40, and is configured to be able to be supplied with refrigerant from the outside. As the refrigerant, for example, ATF (Automatic Transmission Fluid) is used. A refrigerant introduction path 52 is formed in the rotor shaft 40 and extends from the refrigerant flow path 51 to the outer peripheral surface in the radial direction. The refrigerant flow path 51 is connected to a refrigerant supply path 53 formed in the case 80. The rotor shaft 40 is provided with a rotor rotation speed detection section 91 that detects the rotation speed of the rotor 20. The rotor rotational speed detection section 91 is, for example, a resolver.

The rotating electric machine 10 includes a rotor 20 having a substantially annular shape, and a stator 30 having a substantially annular shape and arranged to face each other at a predetermined distance from the outer peripheral surface of the rotor 20 in the radial direction.

The rotor 20 has a substantially annular shape. The rotor 20 includes a rotor core 21 in which a plurality of magnet insertion holes 23 parallel to the axial direction are provided along the circumferential direction on the outer circumferential side, permanent magnets 25 inserted in each magnet insertion hole 23, and a permanent magnet 25 in the axial direction of the rotor core 21. It includes a first end plate 27a disposed on one side and a second end plate 27b disposed on the other side.

The rotor core 21 is constructed by laminating a plurality of substantially annular electromagnetic steel plates in the axial direction. The rotor core 21 has, in the axial direction, a first end surface 21a that is an end surface on one side, and a second end surface 21b that is an end surface on the other side. The rotor core 21 is provided with a plurality of rotor internal channels 54 that are formed to penetrate in the axial direction from the first end surface 21a to the second end surface 21b. In this embodiment, the rotor core 21 is provided with two rotor internal flow passages 54 in the radial direction, one on the outer diameter side and one on the inner diameter side.

The first end plate 27a and the second end plate 27b both have a substantially annular shape that is substantially the same as the rotor core 21 when viewed from the axial direction. In the axial direction, the first end plate 27a is arranged on the first end face 21a side of the rotor core 21, and the second end face plate 27b is arranged on the second end face 21b side of the rotor core 21.

On the axially inner surface of the first end plate 27a facing the first end surface 21a of the rotor core 21, an annular groove 55 that communicates with the coolant introduction passage 52 provided in the rotor shaft 40 is formed at the radially inner end. has been done. Further, on the axially inner surface of the first end plate 27a facing the first end surface 21a of the rotor core 21, an introduction groove 56 is provided that communicates the annular groove 55 with each rotor internal flow path 54 provided in the rotor core 21. There are several. The plurality of introduction grooves 56 extend radially outward from the annular groove 55 in the radial direction.

The second end plate 27b is provided with a plurality of discharge holes 57 extending in the axial direction and extending radially outward from the rotor internal flow path 54 on the outer diameter side along the circumferential direction. On the axially inner surface of the second end plate 27b facing the second end surface 21b of the rotor core 21, there are a plurality of exhaust grooves 58 that communicate each rotor internal flow path 54 provided in the rotor core 21 with the exhaust hole 57. It is provided.

Stator 30 is fixed to case 80 with bolts. The stator 30 is arranged to face the outer peripheral surface of the rotor 20 at a predetermined distance in the radial direction. The stator 30 includes a substantially annular stator core 31 and a coil 33 attached to the stator core 31.

The stator core 31 is constructed by laminating a plurality of approximately annular electromagnetic steel plates in the axial direction. In the axial direction, the stator core 31 has a first end surface 31a that is an end surface on one side (the first end surface 21a side of the rotor core 21), and a second end surface 31b that is an end surface on the other side (the second end surface 21b side of the rotor core 21). and has. The first end surface 31a of the stator core 31 is located at approximately the same axial position as the first end surface 21a of the rotor core 21, and the second end surface 31b of the stator core 31 is located at approximately the same position in the axial direction as the second end surface 21b of the rotor core 21. Almost the same position.

The coil 33 has a first coil end portion 33a that protrudes forward from the first end surface 31a of the stator core 31, and a second coil end portion 33b that protrudes rearward from the second end surface 31b of the stator core 31. Therefore, the first coil end portion 33a protrudes outward in the axial direction from the first end surface 21a of the rotor core 21, and the second coil end portion 33b protrudes outward in the axial direction from the second end surface 21b of the rotor core 21. There is. A coil end temperature detection section 92 that detects the temperature of the second coil end section 33b is installed in the second coil end section 33b. The coil end temperature detection section 92 is, for example, a thermistor.

The refrigerant supplied from the outside to the refrigerant flow path 51 of the rotor shaft 40 is supplied from the refrigerant introduction path 52 to the rotor internal flow path 54 of the rotor core 21 via the annular groove 55 and the introduction groove 56 of the first end plate 27a, It flows through the rotor internal flow path 54 from the first end surface 21a to the second end surface 21b of the rotor core 21 to cool the rotor 20. The refrigerant that cools the rotor 20 and reaches the second end surface 21b of the rotor core 21 is discharged from the discharge hole 57 via the discharge groove 58 of the second end plate 27b. When the rotating electric machine is driving, the rotor 20 is rotating, so the refrigerant discharged from the discharge hole 57 is discharged radially outward due to the centrifugal force of the rotating rotor 20, and the refrigerant is discharged from the second coil end. The coil 33 is cooled from the inner peripheral surface of the portion 33b. In this way, the refrigerant supplied to the refrigerant flow path 51 of the rotor shaft 40 is supplied to the rotor 20 and stator 30 of the rotating electrical machine 10, thereby cooling the rotor 20 and stator 30 of the rotating electrical machine 10.

The refrigerant discharged from the discharge hole 57 is discharged radially outward due to the centrifugal force of the rotor 20, cools the coil 33 from the inner circumferential surface of the second coil end portion 33b, and then falls due to gravity to the case. The oil is stored in an oil pan 81 formed at the bottom of the oil pan 80. A refrigerant temperature detection section 93 is installed in the oil pan 81 of the case 80 to detect the temperature of the stored refrigerant. Refrigerant temperature detection section 93 is, for example, a thermistor.

(refrigerant supply device)
The refrigerant supply device 60 is a device that circulates the refrigerant stored in the oil pan 81 of the case 80 and supplies the refrigerant to the refrigerant passage 51 of the rotor shaft 40 again.

The refrigerant supply device 60 includes a refrigerant circulation path 61 provided with a strainer 62, a pump 63, and an ATF cooler 64, a switching section 65, and a first refrigerant channel 66a and a second refrigerant channel 66b extending from the switching section 65. , is provided. One end of the refrigerant circulation path 61 is connected to the oil pan 81 of the case 80 , and the other end is connected to the switching section 65 .

The strainer 62 filters the refrigerant stored in the oil pan 81 of the case 80 and supplies it to the pump 63 . The pump 63 may be an electric or mechanical pump. ATF cooler 64 cools the refrigerant. The refrigerant stored in the oil pan 81 of the case 80 is driven by the pump 63, filtered by the strainer 62, passed through the refrigerant circulation path 61, cooled by the ATF cooler 64, and supplied to the switching section 65.

The switching unit 65 supplies the refrigerant supplied from the refrigerant circulation path 61 to the first refrigerant flow path 66a and the second refrigerant flow path 66b. The switching unit 65 is, for example, a solenoid valve that opens and closes a valve by moving a plunger using the magnetic force of an electromagnet.

The first refrigerant flow path 66 a is connected to a refrigerant supply path 53 formed in the case 80 , and the refrigerant supplied to the first refrigerant flow path 66 a passes through the refrigerant supply path 53 and is transferred to the refrigerant of the rotor shaft 40 . It is supplied to the flow path 51.

The second refrigerant flow path 66b is not connected to the refrigerant flow path 51 of the rotor shaft 40. Therefore, the refrigerant supplied to the second refrigerant flow path 66b is not supplied to the refrigerant flow path 51 of the rotor shaft 40. For example, the second refrigerant flow path 66b may be directly connected to the oil pan 81 of the case 80, or may be connected to a refrigerant dripping pipe (not shown) provided in the case 80 that drips refrigerant onto the stator 30. You can leave it there.

The switching unit 65 opens and closes the solenoid valve to switch between a refrigerant supply state in which refrigerant is supplied to the first refrigerant flow path 66a and a refrigerant supply stop state in which refrigerant is stopped being supplied to the first refrigerant flow path 66a. Switch. When the switching unit 65 is in the refrigerant supply stop state in which the supply of refrigerant to the first refrigerant flow path 66a is stopped, all of the refrigerant supplied from the refrigerant circulation path 61 is supplied to the second refrigerant flow path 66b. When the switching unit 65 is in the refrigerant supply state in which refrigerant is supplied to the first refrigerant flow path 66a, all of the refrigerant supplied from the refrigerant circulation path 61 may be supplied to the first refrigerant flow path 66a, or all of the refrigerant supplied from the refrigerant circulation path 61 may be The refrigerant may be supplied to both the refrigerant flow path 66a and the second refrigerant flow path 66b.

Therefore, when the switching unit 65 is in the refrigerant supply state in which the refrigerant is supplied to the first refrigerant flow path 66a, the refrigerant is supplied to the refrigerant flow path 51 of the rotor shaft 40 in the axial cooling implementation state, and the switching unit 65 is in the axial cooling execution state. In the refrigerant supply stop state in which the supply of refrigerant to the first refrigerant flow path 66a is stopped, there is a shaft center cooling stop state in which the refrigerant is not supplied to the refrigerant flow path 51 of the rotor shaft 40.

Refrigerant supply device 60 includes a control section 70 that controls switching section 65 . A rotor rotational speed detection section 91, a coil end temperature detection section 92, and a refrigerant temperature detection section 93 are connected to the control section 70.

The control unit 70 includes a refrigerant temperature calculation unit 71, a coil temperature calculation unit 72, a magnet temperature calculation unit 73, and a rotor rotation speed calculation unit 74.

The refrigerant temperature calculation section 71 calculates the rotation speed of the rotor 20, the temperature of the second coil end section 33b, and the oil pan 81 detected by the rotor rotation speed detection section 91, the coil end temperature detection section 92, and the refrigerant temperature detection section 93. A refrigerant temperature Tr, which is the temperature of the refrigerant circulating in the rotating electric machine unit 1, is calculated based on the temperature of the refrigerant stored in the rotary electric machine unit 1. The refrigerant temperature Tr is determined by the rotational speed of the rotor 20, the temperature of the second coil end portion 33b, and the temperature stored in the oil pan 81, which are detected by the rotor rotational speed detection section 91, the coil end temperature detection section 92, and the refrigerant temperature detection section 93. The calculation may be based on one or two of the refrigerant temperatures.

The coil temperature calculation unit 72 calculates the rotation speed of the rotor 20, the temperature of the second coil end portion 33b, and the oil pan 81 detected by the rotor rotation speed detection unit 91, the coil end temperature detection unit 92, and the refrigerant temperature detection unit 93. The coil temperature Tc, which is the temperature of the coil 33, is calculated based on the temperature of the refrigerant stored in the coil 33. The coil temperature Tc may be calculated based on any one or two of the rotational speed of the rotor 20, the temperature of the second coil end portion 33b, and the temperature of the refrigerant stored in the oil pan 81. It is preferable that the coil temperature Tc is the temperature at the central portion of the coil 33 in the axial direction, which is calculated by estimation.

The magnet temperature calculation section 73 calculates the rotation speed of the rotor 20, the temperature of the second coil end section 33b, and the oil pan 81 detected by the rotor rotation speed detection section 91, the coil end temperature detection section 92, and the refrigerant temperature detection section 93. The magnet temperature Tm, which is the temperature of the permanent magnet 25 of the rotor 20, is estimated based on the temperature of the refrigerant stored in the rotor 20. The magnet temperature Tm may be calculated by estimation based on any one or two of the rotational speed of the rotor 20, the temperature of the second coil end portion 33b, and the temperature of the refrigerant stored in the oil pan 81. Further, the magnet temperature Tm can be calculated based on the magnet temperature detected by the magnet temperature detection section by providing a magnet temperature detection section that detects the temperature of the permanent magnet 25 of the rotor 20 and connecting it to the control section 70. Good too.

The rotor rotational speed calculation section 74 calculates the rotor rotational speed Rev, which is the rotational speed of the rotor 20, based on the rotational speed of the rotor 20 detected by the rotor rotational speed detection section 91.

(Control of switching section)
Next, control of the switching section 65 in the control section 70 will be explained with reference to FIG. 3.

First, the process proceeds to step S110. In step S110, the refrigerant temperature Tr calculated by the refrigerant temperature calculation unit 71 is in a temperature range of not less than the first predetermined refrigerant temperature Tr1 and not more than a second predetermined refrigerant temperature Tr2 higher than the first predetermined refrigerant temperature Tr1. It is determined whether the temperature is within a predetermined refrigerant temperature range. If the refrigerant temperature Tr is within the predetermined refrigerant temperature range that is greater than or equal to the first predetermined refrigerant temperature Tr1 and less than or equal to the second predetermined refrigerant temperature Tr2, the process proceeds to step S202, and the refrigerant temperature Tr is set to the first predetermined refrigerant temperature. If the temperature is not within the predetermined refrigerant temperature range that is equal to or higher than Tr1 and equal to or lower than the second predetermined refrigerant temperature Tr2, the process proceeds to step S120. The first predetermined refrigerant temperature Tr1 is, for example, the lowest temperature at which warming up of the refrigerant is not required. The first predetermined refrigerant temperature Tr1 is, for example, 30°C. The second predetermined refrigerant temperature Tr2 is, for example, the maximum temperature at which the rotating electric machine 10 can be sufficiently cooled even if no refrigerant is supplied from the refrigerant flow path 51 of the rotor shaft 40. The second predetermined refrigerant temperature Tr2 is, for example, 80°C.

In step S120, it is determined whether the coil temperature Tc calculated by the coil temperature calculation unit 72 is less than a predetermined coil temperature Tcs. If the coil temperature Tc is less than the predetermined coil temperature Tcs, the process proceeds to step S202, and if the coil temperature Tc is not less than the predetermined coil temperature Tcs, the process proceeds to step S130. The predetermined coil temperature Tcs is, for example, the maximum temperature at which the coil 33 can be sufficiently cooled even if no refrigerant is supplied from the refrigerant flow path 51 of the rotor shaft 40. The predetermined coil temperature Tcs is, for example, 100°C.

In step S130, it is determined whether the magnet temperature Tm calculated by the magnet temperature calculation unit 73 is less than a predetermined magnet temperature Tms. If the magnet temperature Tm is less than the predetermined magnet temperature Tms, the process proceeds to step S202, and if the magnet temperature Tm is not less than the predetermined magnet temperature Tms, the process proceeds to step S140. The predetermined magnet temperature Tms is, for example, the maximum temperature at which the permanent magnet 25 can be sufficiently cooled even if no refrigerant is supplied from the refrigerant flow path 51 of the rotor shaft 40. The predetermined magnet temperature Tms is, for example, 100°C.

In step S140, it is determined whether the rotor rotation speed Rev calculated by the rotor rotation speed calculation unit 74 is less than a predetermined rotor rotation speed Rev-s. If the rotor rotational speed Rev is less than the predetermined rotor rotational speed Rev-s, the process proceeds to step S202, and if the rotor rotational speed Rev is not less than the predetermined rotor rotational speed Rev-s, the process proceeds to step S201. The predetermined rotor rotational speed Rev-s is, for example, the maximum speed at which the rotating electric machine 10 can be sufficiently cooled even if no refrigerant is supplied from the refrigerant flow path 51 of the rotor shaft 40. The predetermined rotor rotation speed Rev-s is, for example, 8000 rpm.

In step S201, the control unit 70 controls the switching unit 65 to enter a refrigerant supply state in which refrigerant is supplied to the first refrigerant flow path 66a. That is, the control unit 70 controls the switching unit 65 so as to enter the axial cooling implementation state in which the refrigerant is supplied to the refrigerant flow path 51 of the rotor shaft 40 . Then, the process advances to step S300.

In step S202, the control unit 70 controls the switching unit 65 to enter a refrigerant supply stop state in which the supply of refrigerant to the first refrigerant flow path 66a is stopped. That is, the control unit 70 controls the switching unit 65 so that the cooling of the shaft center is stopped, in which the refrigerant is not supplied to the refrigerant flow path 51 of the rotor shaft 40 . Then, the process advances to step S300.

In step S300, it is determined whether the control of the switching section 65 in the control section 70 is to be ended. If the control of the switching unit 65 in the control unit 70 is to be ended, the control is ended, and if the control of the switching unit 65 in the control unit 70 is not to be ended, the process returns to step S110.

By the way, when the refrigerant is discharged radially outward from the discharge hole 57 of the second end plate 27b, a part of the refrigerant flows between the rotor 20 and the stator 30, and then flows between the rotor 20 and the stator 30. The output efficiency of the rotating electrical machine 10 decreases due to the viscous resistance of the refrigerant.

When the coolant is not supplied to the coolant passage 51 of the rotor shaft 40 and the shaft core cooling is stopped, the coolant is not discharged radially outward from the discharge hole 57 of the second end plate 27b, so that the rotor 20 and the stator 30 The amount of refrigerant flowing during this period is reduced, and a decrease in the output efficiency of the rotating electric machine 10 is suppressed.

The control unit 70 is configured so that when the refrigerant temperature Tr calculated by the refrigerant temperature calculation unit 71 is within a predetermined refrigerant temperature range, the shaft center cooling is stopped in which no refrigerant is supplied to the refrigerant flow path 51 of the rotor shaft 40. Since the switching unit 65 is controlled, the amount of refrigerant flowing between the rotor 20 and the stator 30 is reduced, and a decrease in the output efficiency of the rotating electric machine 10 can be suppressed. Furthermore, if the refrigerant temperature Tr calculated by the refrigerant temperature calculation unit 71 is within the predetermined refrigerant temperature range, the cooling efficiency of the rotating electric machine 10 will not decrease even if no refrigerant is supplied to the refrigerant flow path 51 of the rotor shaft 40. .

In this way, when the refrigerant temperature Tr calculated by the refrigerant temperature calculation unit 71 is within the predetermined refrigerant temperature range, the control unit 70 causes the shaft center cooling to stop so that the refrigerant is not supplied to the refrigerant flow path 51 of the rotor shaft 40. Since the switching unit 65 is controlled so as to be in the state, a decrease in the output efficiency of the rotating electrical machine 10 can be suppressed without reducing the cooling efficiency of the rotating electrical machine 10.

Furthermore, since the predetermined refrigerant temperature range is a temperature range that is equal to or higher than the first predetermined refrigerant temperature Tr1 and equal to or lower than the second predetermined refrigerant temperature Tr2, there is no need to warm up the refrigerant, and the rotating electric machine 10 is at a low temperature and does not require cooling. In some cases, the cooling of the shaft core can be stopped, and a decrease in the output efficiency of the rotating electrical machine 10 can be suppressed without reducing the cooling efficiency of the rotating electrical machine 10.

Further, when the coil temperature Tc calculated by the coil temperature calculation unit 72 is less than the predetermined coil temperature Tcs, the control unit 70 enters an axial center cooling stop state in which the refrigerant is not supplied to the refrigerant flow path 51 of the rotor shaft 40. Since the switching unit 65 is controlled in this way, when the coil 33 is at a low temperature and does not require cooling, the shaft core cooling can be stopped, and the output efficiency of the rotating electrical machine 10 can be increased without reducing the cooling efficiency of the rotating electrical machine 10. The decline can be suppressed.

Further, when the magnet temperature Tm calculated by the magnet temperature calculation unit 73 is less than the predetermined magnet temperature Tms, the control unit 70 sets the shaft center cooling stop state in which no refrigerant is supplied to the refrigerant flow path 51 of the rotor shaft 40. Since the switching unit 65 is controlled so that the cooling of the rotor 20 is stopped when the permanent magnet 25 of the rotor 20 is at a low temperature and does not require cooling, the rotating electrical machine 10 can be cooled without reducing the cooling efficiency of the rotating electrical machine 10. 10 can be suppressed from decreasing in output efficiency.

Further, the control unit 70 controls a shaft to which the refrigerant is not supplied to the refrigerant passage 51 of the rotor shaft 40 when the rotor rotation speed Rev calculated by the rotor rotation speed calculation unit 74 is less than a predetermined rotor rotation speed Rev-s. Since the switching unit 65 is controlled to bring the heart cooling to a halt state, the shaft core cooling can be brought to a halt state when the rotational speed of the rotor 20 is low and the temperature of the rotating electrical machine 10 is difficult to rise, and the rotating electrical machine A decrease in the output efficiency of the rotating electrical machine 10 can be suppressed without reducing the cooling efficiency of the rotating electrical machine 10.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and can be modified, improved, etc. as appropriate.

Furthermore, this specification describes at least the following matters. Note that, although components corresponding to those in the above-described embodiment are shown in parentheses, the present invention is not limited thereto.

(1) A rotating electrical machine (rotating electrical machine 10) having a rotor (rotor 20) and a stator (stator 30),
a rotor shaft (rotor shaft 40) that is rotatably connected to the rotor and provided with a refrigerant flow path (refrigerant flow path 51) through which a refrigerant flows;
A refrigerant supply device (refrigerant supply device 60) that supplies the refrigerant to the refrigerant flow path,
A rotating electrical machine unit (rotating electrical machine unit 1) in which the refrigerant passing through the refrigerant flow path is supplied to the rotor and the stator to cool the rotating electrical machine,
The refrigerant supply device includes:
a switching unit (switching unit 65) that switches between a shaft cooling implementation state in which the refrigerant is supplied to the refrigerant flow path and a shaft cooling stop state in which the refrigerant is not supplied to the refrigerant flow path;
A control unit (control unit 70) that controls the switching unit,
The control unit includes:
A refrigerant temperature calculation unit (refrigerant temperature calculation unit 71) that calculates a refrigerant temperature (refrigerant temperature Tr) that is the temperature of the refrigerant,
A rotating electrical machine unit that controls the switching unit to enter the shaft core cooling stop state when the refrigerant temperature calculated by the refrigerant temperature calculation unit is within a predetermined refrigerant temperature range.

According to (1), when the refrigerant temperature calculated by the refrigerant temperature calculation unit is within a predetermined refrigerant temperature range, the control unit determines the shaft center cooling stop state in which refrigerant is not supplied to the refrigerant flow path of the rotor shaft. Since the switching unit is controlled so that the amount of refrigerant flowing between the rotor and the stator is reduced, it is possible to suppress a decrease in the output efficiency of the rotating electric machine. Furthermore, it is possible to set the predetermined refrigerant temperature range to a temperature range in which the cooling efficiency of the rotating electric machine does not decrease even if the refrigerant is not supplied to the coolant flow path of the rotor shaft, so there is no need to reduce the cooling efficiency of the rotating electric machine. , it is possible to suppress a decrease in the output efficiency of the rotating electric machine.

(2) The rotating electric machine unit according to (1),
The predetermined refrigerant temperature range is a temperature range that is not less than a first predetermined refrigerant temperature (first predetermined refrigerant temperature Tr1) and not more than a second predetermined refrigerant temperature (second predetermined refrigerant temperature Tr2) higher than the first predetermined refrigerant temperature. A rotating electric machine unit.

According to (2), the predetermined refrigerant temperature range is a temperature range that is above the first predetermined refrigerant temperature and below the second predetermined refrigerant temperature, so there is no need to warm up the refrigerant and the rotating electric machine is cooled at a low temperature. When it is not necessary, the cooling of the shaft core can be stopped, and a decrease in the output efficiency of the rotating electrical machine can be suppressed without reducing the cooling efficiency of the rotating electrical machine.

(3) The rotating electric machine unit according to (1) or (2),
The stator includes a coil (coil 33),
The control unit includes:
A coil temperature calculation unit (coil temperature calculation unit 72) that calculates a coil temperature (coil temperature Tc) that is the temperature of the coil,
A rotating electric machine unit that controls the switching section so that the shaft core cooling is stopped when the coil temperature is less than a predetermined coil temperature (predetermined coil temperature Tcs).

According to (3), when the coil temperature calculated by the coil temperature calculation unit is lower than the predetermined coil temperature, the shaft center cooling is stopped in which no refrigerant is supplied to the refrigerant flow path of the rotor shaft, so the coil is at a low temperature. When cooling is not required, the shaft core cooling can be stopped, and a decrease in the output efficiency of the rotating electrical machine can be suppressed without reducing the cooling efficiency of the rotating electrical machine.

(4) The rotating electric machine unit according to any one of (1) to (3),
The rotor includes a permanent magnet (permanent magnet 25),
The control unit includes:
A magnet temperature calculation unit (magnet temperature calculation unit 73) that calculates a magnet temperature (magnet temperature Tm) that is the temperature of the permanent magnet,
A rotating electric machine unit that controls the switching section so that the shaft core cooling is stopped when the magnet temperature is less than a predetermined magnet temperature (predetermined magnet temperature Tms).

According to (4), when the magnet temperature calculated by the magnet temperature calculation unit is lower than the predetermined magnet temperature, the shaft core cooling is stopped in which refrigerant is not supplied to the refrigerant flow path of the rotor shaft. When the temperature is low and cooling is not necessary, the cooling of the shaft core can be stopped, and a decrease in the output efficiency of the rotating electrical machine can be suppressed without reducing the cooling efficiency of the rotating electrical machine.

(5) The rotating electric machine unit according to any one of (1) to (4),
The control unit includes:
A rotor rotation speed calculation unit (rotor rotation speed calculation unit 74) that calculates a rotor rotation speed (rotor rotation speed Rev) that is the rotation speed of the rotor,
A rotating electric machine unit that controls the switching section so that the shaft core cooling is stopped when the rotor rotation speed is less than a predetermined rotor rotation speed (predetermined rotor rotation speed Rev-s).

According to (5), when the rotor rotation speed calculated by the rotor rotation speed calculation section is less than the predetermined rotor rotation speed, the shaft center cooling is stopped in which no refrigerant is supplied to the refrigerant flow path of the rotor shaft. , when the rotational speed of the rotor is low and the temperature of the rotating electric machine is difficult to rise, the shaft center cooling can be stopped, and the output efficiency of the rotating electric machine can be reduced without reducing the cooling efficiency of the rotating electric machine. It can be suppressed.

1 Rotating electrical machine unit 10 Rotating electrical machine 20 Rotor 25 Permanent magnet 30 Stator 33 Coil 40 Rotor shaft 51 Refrigerant flow path 60 Refrigerant supply device 65 Switching section 70 Control section 71 Refrigerant temperature calculation section 72 Coil temperature calculation section 73 Magnet temperature calculation section 74 Rotor Rotation speed calculation unit Tr Refrigerant temperature Tr1 First predetermined refrigerant temperature Tr2 Second predetermined refrigerant temperature Tc Coil temperature Tcs Predetermined coil temperature Tm Magnet temperature Tms Predetermined magnet temperature Rev Rotor rotation speed Rev-s Predetermined rotor rotation speed

Claims (4)

A rotating electric machine having a rotor and a stator;
a rotor shaft that is rotatably connected to the rotor and is provided with a refrigerant flow path through which refrigerant flows;
a refrigerant supply device that supplies the refrigerant to the refrigerant flow path,
A rotating electrical machine unit in which the refrigerant passing through the refrigerant flow path is supplied to the rotor and the stator to cool the rotating electrical machine,
The refrigerant supply device includes:
a switching unit that switches between a shaft cooling implementation state in which the refrigerant is supplied to the refrigerant flow path and a shaft cooling stop state in which the refrigerant is not supplied to the refrigerant flow path;
a control section that controls the switching section;
The control unit includes:
comprising a refrigerant temperature calculation unit that calculates a refrigerant temperature that is the temperature of the refrigerant;
When the refrigerant temperature calculated by the refrigerant temperature calculation unit is within a predetermined refrigerant temperature range, controlling the switching unit so that the shaft center cooling is stopped;
The predetermined refrigerant temperature range is a temperature range that is equal to or higher than a first predetermined refrigerant temperature and equal to or lower than a second predetermined refrigerant temperature higher than the first predetermined refrigerant temperature . The rotating electrical machine unit according to claim 1 ,
The stator includes a coil,
The control unit includes:
comprising a coil temperature calculation unit that calculates a coil temperature that is the temperature of the coil,
A rotating electric machine unit that controls the switching section so that the shaft core cooling is stopped when the coil temperature is less than a predetermined coil temperature. The rotating electric machine unit according to claim 1 or 2 ,
The rotor includes a permanent magnet,
The control unit includes:
comprising a magnet temperature calculation unit that calculates a magnet temperature that is the temperature of the permanent magnet,
A rotating electric machine unit that controls the switching section so that the shaft core cooling is stopped when the magnet temperature is less than a predetermined magnet temperature. The rotating electric machine unit according to any one of claims 1 to 3 ,
The control unit includes:
comprising a rotor rotation speed calculation unit that calculates a rotor rotation speed that is the rotation speed of the rotor,
A rotating electric machine unit that controls the switching section so that the shaft core cooling is stopped when the rotor rotation speed is less than a predetermined rotor rotation speed.

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