JP2024068063A - Rotating electric machine unit control device - Google Patents

Abstract

[Problem] An object of the present invention is to efficiently drive an oil pump to ensure insulation in a coil provided in a rotating electric machine. [Solution] A control device for a rotating electric machine unit controls a rotating electric machine unit including a rotating electric machine and an oil supply unit including an oil pump that supplies oil to a coil provided in the rotating electric machine. The control device includes an information acquisition unit that acquires information on air density inside the coil and information on a voltage applied to the rotating electric machine, an insulation determination unit that performs an insulation determination for the coil based on the air density information and the voltage information acquired by the information acquisition unit, and a drive instruction unit that drives the oil supply unit when the insulation determination unit determines that the insulation of the coil is low and that it is necessary to maintain the insulation state by supplying oil. [Selected Figure] Figure 4

Description

The present invention relates to a control device for a rotating electrical unit.

Conventionally, oil pumps are used to supply oil to coils in motors serving as rotating electrical machines (see, for example, Patent Document 1). There have also been proposals to supply oil as an insulating material in coils (see, for example, Patent Document 2). Oil is supplied by electric oil pumps or mechanical oil pumps.

JP 2019-161948 A JP 2012-151995 A

However, if the oil pump is electrically operated, power is consumed by the operation of the oil pump, and drive losses occur when the pump is driven, resulting in poor electricity consumption. Even if the oil pump is mechanical, drive losses occur when the pump is driven. For this reason, in order to improve electricity consumption and reduce drive losses when the pump is driven, it is desirable to operate the oil pump less frequently. However, in Patent Document 2, there is room for improvement in terms of ensuring insulation while reducing losses when driving the pump.

Therefore, the objective of the invention disclosed in this specification is to drive the oil pump efficiently and ensure insulation in the coils of the rotating electric machine.

The above problem is achieved by a control device for a rotating electric machine unit including a rotating electric machine and an oil supply unit including an oil pump that supplies oil to a coil included in the rotating electric machine, the control device for a rotating electric machine unit including an information acquisition unit that acquires information related to the air density in the coil and information related to the voltage applied to the rotating electric machine, an insulation determination unit that determines whether or not insulation breakdown will occur in the coil based on the information related to the air density and the information related to the voltage acquired by the information acquisition unit, and a drive instruction unit that drives the oil supply unit when the insulation determination unit determines that insulation breakdown will occur in the coil and that it is necessary to maintain the insulation state by supplying oil.

In the control device for a rotating electrical machine unit having the above configuration, the information acquisition unit can acquire information on the air temperature inside the coil and information on atmospheric pressure as the information on the air density.

In addition, in the control device for the rotating electric machine unit having the above configuration, the information acquisition unit can acquire the detected temperature of the coil or the detected temperature of the oil as information on the air temperature inside the coil.

Furthermore, in the control device for the rotating electric machine unit having the above configuration, the information acquisition unit may acquire, as the information regarding the atmospheric pressure, a detection value of an atmospheric pressure sensor, or altitude information acquired by a position information acquisition device provided in a vehicle on which the rotating electric machine is mounted.

In the control device for a rotating electric machine unit having the above configuration, the oil pump is a mechanical pump that is driven by the operation of the internal combustion engine, and the drive instruction unit may further include an applied voltage limiting unit that drives the rotating electric machine to start the internal combustion engine when the insulation determination unit determines that insulation breakdown will occur in the coil and that it is necessary to maintain the insulation state by supplying oil, and that limits the voltage applied to the rotating electric machine when driving the rotating electric machine to start the internal combustion engine based on the instruction of the drive instruction unit.

Another control device for a rotating electric machine unit disclosed in this specification is a control device for a rotating electric machine unit that includes a rotating electric machine, a gear mechanism that is driven by the rotating electric machine and at least a portion of which is immersed in oil, and an oil supply unit that supplies the oil to a coil included in the rotating electric machine by operating the gear mechanism, and that includes an information acquisition unit that acquires information about the air density in the coil and information about the voltage applied to the rotating electric machine, an insulation determination unit that determines whether or not insulation breakdown will occur in the coil based on the information about the air density and the information about the voltage acquired by the information acquisition unit, a drive instruction unit that drives the rotating electric machine when the insulation determination unit determines that insulation breakdown will occur in the coil and that it is necessary to maintain the insulation state by supplying oil, and an applied voltage limiting unit that limits the voltage applied to the rotating electric machine when the rotating electric machine is driven by an instruction from the drive instruction unit.

The invention disclosed in this specification makes it possible to drive the oil pump efficiently and ensure insulation in the coils of the rotating electric machine.

FIG. 1 is a schematic diagram showing the configuration of a vehicle equipped with a rotating electrical machine unit according to a first embodiment. FIG. 2 is an explanatory diagram showing an outline of the rotating electrical machine unit according to the first embodiment. FIG. 3 is a cross-sectional view of the rotating electrical machine unit of the first embodiment taken along line AA in FIG. FIG. 4 is a flowchart showing an example of control executed by the control device for the rotating electrical machine unit according to the first embodiment. FIG. 5 is a diagram showing an example of an oil pump operation map in the control device for the rotating electrical machine unit according to the first embodiment. FIG. 6 is a schematic diagram showing the main parts of a vehicle equipped with a rotating electrical machine unit according to the second embodiment. FIG. 7 is a schematic diagram showing the configuration of a vehicle equipped with a rotating electrical machine unit according to the third embodiment. FIG. 8 is a flowchart showing an example of control executed by the control device for a rotating electrical machine unit according to the third embodiment. FIG. 9 is an example of a map for setting the output torque of the first motor generator in the third embodiment. FIG. 10 is an explanatory diagram showing an outline of a rotating electrical machine unit according to the fourth embodiment. FIG. 11 is a flowchart showing an example of control executed by the control device for a rotating electrical machine unit according to the fourth embodiment.

Embodiments of the present invention will be described below with reference to the attached drawings. However, the dimensions and ratios of each part in the drawings may not be illustrated to be exactly the same as the actual ones. Also, some details may be omitted in the drawings.

First Embodiment
[vehicle]
First, a vehicle 20 equipped with a rotating electric machine unit 100 according to a first embodiment will be described with reference to Fig. 1. The rotating electric machine unit 100 includes a motor 30, which is an example of a rotating electric machine, and an oil supply unit 60 that supplies oil to a coil (see Fig. 2) included in the motor 30. The vehicle 20 also includes an ECU (Electronic Control Unit) 70 that performs various controls of the vehicle 20.

The vehicle 20 is an electric vehicle. The vehicle 20 includes a battery 58, which is a chargeable and dischargeable secondary battery, a boost converter 57 that boosts the DC voltage of the battery, and an inverter 56. The inverter 56 converts the DC power boosted by the boost converter 57 into three-phase AC power by switching the DC power with a switching element. The three-phase AC power converted by the inverter 56 is supplied to the motor 30. The output shaft 22 of the motor 30 is transmitted to the drive wheels 26 via the differential gear 24, so that the vehicle 20 can run. The vehicle 20 of this embodiment is an electric vehicle, but it may also be a hybrid vehicle equipped with an engine as long as it uses the motor 30 as a drive source. The motor 30 not only generates the drive force of the vehicle 20 in response to the power supply from the battery 58, but also functions as a motor generator that generates power by power transmission from the drive wheels 26 of the vehicle 20 and charges the battery 58.

<Configuration of Rotating Electric Machine Unit>
Here, the configuration of the rotating electrical machine unit 100 will be described in detail.

<Motor configuration>
2 and 3, the motor 30 will be described. The motor 30 includes a rotor 32 and a stator 40 housed in a case 46.

The stator 40 includes a stator core 42, which is a generally cylindrical magnetic component. The stator core 42 is formed, for example, by stacking magnetic plates such as electromagnetic steel plates in the axial direction. A plurality of segment conductors are arranged in the stator core 42 to form a coil 44. The coil 44 includes a three-phase coil, that is, a U-phase coil, a V-phase coil, and a W-phase coil. The coil 44 may be wound around the teeth of the stator core 42 using concentrated winding.

The rotor 32 is provided with a rotor core 34 that is concentric with and faces the stator 40 on the radially inner side of the stator 40. An output shaft 22, which is a rotating shaft member, is provided in the center of the rotor core 34. The output shaft 22 is supported by a bearing portion provided in the case 46 and a lid portion (not shown). The rotor core 34 may be equipped with a permanent magnet.

An oil supply port 46a is provided at the top of the case 46, through which oil is introduced to be supplied to the coil 44 by an oil supply unit 60, which will be described later. An oil discharge port 46b is provided at the bottom of the case 46, through which the oil supplied to the case 46 is discharged.

<Oil supply section configuration>
Next, the oil supply unit 60 will be described. The oil supply unit 60 includes an oil pan 62 provided under the motor 30, an oil supply pipe 66 in which an oil pump 64 is disposed, and an oil shower pipe 68 connected to the oil supply pipe 66. In Figures 2 and 3, arrows indicate the flow of oil and the oil being sprayed.

Oil is stored in the oil pan 62. The lower end of the oil supply pipe 66 is disposed within the oil pan 62, and the oil in the oil pan 62 is sucked up by operating the oil pump 64. An oil temperature sensor 82, which will be described later, is provided on the oil supply pipe 66. A heat exchanger for cooling the oil may be provided downstream of the oil temperature sensor 82 in the oil supply unit 60.

The oil shower pipe 68 is disposed above the motor 30. The oil shower pipe 68 is connected to the oil supply pipe 66, and sprays the oil pumped up by the oil pump 64 toward the motor 30. The oil sprayed from the oil shower pipe 68 is introduced into the case 46 from the oil supply port 46a. The oil introduced into the case 46 is supplied to the coil 44 housed in the case 46. The oil cools the coil 44 and also functions as an insulating material in the coil 44, improving the insulation resistance of the coil 44.

In this embodiment, the oil pump 64 is electrically driven and is driven based on a drive command from the drive command unit 70c (see FIG. 1), which will be described later.

<Configuration of control unit>
Next, the ECU 70 will be described. The ECU 70 includes a central processing unit (CPU), a random access memory (RAM), a read only memory (ROM), and a storage device. The ECU 70 controls the vehicle 20 by executing programs stored in the ROM and the storage device. The ECU 70 is electrically connected to an ignition 80, a coil temperature sensor 81, an oil temperature sensor 82, and an atmospheric pressure sensor 83. The ECU 70 is also electrically connected to a global positioning system (GPS) altitude information acquisition unit 84 and a voltage sensor 85. The ECU 70 is further electrically connected to a state of charge (SOC) sensor 59 connected to a battery 58. The ECU 70 is electrically connected to various sensors for controlling the vehicle 20 in addition to the above, but detailed descriptions of these sensors will be omitted here.

The ignition 80 is a switch for putting the vehicle 20 into a state in which it can be driven. The coil temperature sensor 81 is installed near the coil 44 and detects the temperature of the coil 44. The oil temperature sensor 82 detects the temperature of the oil supplied to the coil 44. The atmospheric pressure sensor 83 detects the atmospheric pressure of the environment in which the vehicle 20 is located. The GPS altitude information acquisition unit 84 extracts altitude information from position information detected by a position information detection unit provided in the car navigation system (position information acquisition device). The voltage sensor 85 detects the voltage boosted by the boost converter 57. The SOC sensor 59 detects the remaining capacity SOC of the battery 58.

The ECU 70 determines whether the motor 30 is placed in an environment that requires the supply of oil as an insulating material, and if the supply of oil is required, executes control to drive the oil pump 64 and supply oil to the coil 44. To execute such control, the ECU 70 functions as an information acquisition unit 70a, an insulation determination unit 70b, and a drive instruction unit 70c.

The insulation determination unit 70b determines whether or not insulation breakdown, i.e., a short circuit, will occur in the coil 44. Here, the determination of whether or not insulation breakdown will occur includes not only cases where insulation breakdown actually occurs, but also cases where there is a possibility of insulation breakdown occurring. A threshold value for whether or not insulation breakdown will occur can be set by experiment, simulation, etc. The information acquisition unit 70a acquires various information that the insulation determination unit 70b uses to determine the insulation properties of the coil 44. The drive instruction unit 70c drives the oil pump 64 when the insulation determination unit 70b determines that oil needs to be supplied to the coil 44.

Here, information for determining the insulation of the coil 44 will be described. The insulation of the coil 44 is affected by the air density inside the coil 44, that is, between the wires such as the segment conductors and windings that form the coil 44, and the voltage applied to the coil 44. Specifically, when the air density decreases and the voltage applied to the coil 44 increases, the insulation decreases. Therefore, in this embodiment, information on the air density and information on the voltage applied to the motor 30 (coil 44) (motor applied voltage) are obtained, and the insulation is determined based on this information.

Air density is affected by air temperature and atmospheric pressure. Therefore, in this embodiment, in order to take into account the influence of air density, information on air temperature and atmospheric pressure is acquired by the information acquisition unit 70a.

Because it is difficult to directly detect the air temperature inside the coil 44, in this embodiment, the coil temperature, which has a correlation with the air temperature, is detected and used as the air temperature. The coil temperature is detected by the coil temperature sensor 81. Note that the oil temperature detected by the oil temperature sensor 82 may be acquired as information, as a value that has a correlation with the air temperature. In addition, a thermal circuit network is formed in the vehicle 20, in which heat is exchanged at various locations. Thus, the temperature estimated based on the exchange of heat in this thermal circuit network can be used as information of a value that has a correlation with the air temperature.

The atmospheric pressure is detected by an atmospheric pressure sensor 83 installed in the vehicle 20. In a vehicle equipped with a navigation system, such as the vehicle 20 of this embodiment, the atmospheric pressure may be estimated based on altitude information extracted from the position information detected by the position information detection device.

The voltage applied to the motor 30 is detected by a voltage sensor 85 that detects the voltage boosted by the boost converter 57. Note that the voltage at another location in the vehicle 20 may be used as information as long as it is a value that can be used to evaluate the voltage applied to the motor 30. For example, the voltage that can be applied to the motor 30 may be estimated based on the remaining capacity SOC of the battery 58 detected by the SOC sensor 59, and this value may be used as information. In addition, if the vehicle does not have a boost system such as the boost converter 57, the voltage of the battery 58 may be used as information. In addition, a surge voltage may occur in the vehicle 20 due to various causes, and when the occurrence of a surge voltage is predicted, the predicted surge voltage may be used as information. This makes it possible to protect the motor 30.

[Oil supply control]
Next, an example of oil supply control will be described with reference to FIGS.

In step S1, the ECU 70 determines whether the ignition 80 is turned on. If the ECU 70 determines yes in step S1, the ECU 70 proceeds to step S2. On the other hand, if the ECU 70 determines no in step S1, the ECU 70 repeats the process of step S1 until it determines yes in step S1.

In step S2, the ECU 70, specifically the information acquisition unit 70a, acquires various information for determining whether or not insulation is ensured in the coil 44 (see FIG. 2). That is, the information acquisition unit 70a acquires the coil temperature as the air temperature inside the coil from the coil temperature sensor 81, and acquires the atmospheric pressure as the air pressure inside the coil from the atmospheric pressure sensor 83. The information acquisition unit 70a also acquires the voltage boosted by the boost converter 57 from the voltage sensor 85 as the motor applied voltage.

In step S3, which is executed following step 2, the insulation determination unit 70b determines the insulation of the coil 44. The insulation determination unit 70b performs the insulation determination based on the oil pump operation map shown in FIG. 5. If the determination in step S3 is negative, that is, if it is determined that the insulation of the coil 44 is not ensured, the process proceeds to step S4. In step S4, the drive instruction unit 70c issues an instruction to drive the oil pump 64. On the other hand, if the insulation determination unit 70b makes a positive determination in step S3, the ECU 70 repeats the process from step S1.

The oil pump operation map shown in Figure 5 will now be described. The oil pump operation map is composed of three parameters: the motor applied voltage (indicated as "Voltage" in the map) applied to the motor 30, the coil temperature, and the altitude. Specifically, the insulation is determined by the combination of the coil temperature and altitude set for each voltage, and based on the result, it is determined whether or not to operate the oil pump 64. In Figure 5, the hatched areas indicate a state in which insulation cannot be ensured and it is determined that the oil pump 64 should be operated.

The higher the motor applied voltage, the more difficult it is to ensure insulation. Also, the higher the coil temperature (air temperature inside the coil) and the higher the altitude, the lower the air density, making it more difficult to ensure insulation. For this reason, in the oil pump operation map, the higher the motor applied voltage, the more frequently the motor 30 is operated. In other words, even if the coil temperature and altitude are the same, the higher the motor applied voltage, the more frequently the motor is operated. For this reason, even if the coil temperature and altitude are low, that is, the air density is high, the more frequently the motor 30 is operated. Also, even if the motor applied voltage and altitude are the same, the higher the coil temperature, the more frequently the motor is operated. Also, even if the motor applied voltage and altitude are the same, the higher the coil temperature, the more frequently the motor is operated.

If the insulation determination unit 70b makes a negative determination in step S3, the process proceeds to step S4, where the oil pump 64 is started to be driven. Then, the process proceeds to step S5, where the ECU 70 determines whether or not t seconds have elapsed since the oil pump 64 was started to be driven. This t seconds is a time that is set in advance by experiment or simulation as the oil supply time that can operate the oil pump 64 and improve the insulation resistance of the coil 44. If the ECU 7 makes a positive determination in step S5, the process proceeds to step S6, where the oil pump 64 is stopped to be driven. On the other hand, if the ECU 70 makes a negative determination in step S5, the process repeats the process of step S5, and continues to drive the oil pump 64, until a positive determination is made in step S5.

In step S7, which is executed following step S6, the ECU 70 determines whether the ignition 80 has been turned off. If the ECU 70 determines negative in step S7, it repeats the process from step S1. As a result, when the ignition 80 is in the ON state, the oil supply control continues. On the other hand, if the ECU 70 determines positive in step S7, it ends the series of processes (END).

As described above, according to this embodiment, when the insulation determination unit 70b determines that oil needs to be supplied to the coil 44, the oil pump 64 is driven to supply oil to the coil. In this way, since the oil pump 64 is driven based on the insulation determination of the insulation determination unit 70b, the frequency of operation of the oil pump can be reduced. In addition, the insulation resistance of the coil 44 can be improved, and the insulation of the coil 44 can be ensured.

Second Embodiment
[Rotating electric units in hybrid vehicles]
Next, a second embodiment will be described with reference to Fig. 6. A vehicle 120 in the second embodiment is a hybrid vehicle equipped with an engine 122. That is, the second embodiment is an embodiment in which a vehicle 120, which is a hybrid vehicle, is equipped with a rotating electrical machine unit 200. Note that components common to the first embodiment are given the same reference numerals in the drawings, and detailed descriptions thereof will be omitted.

The vehicle 120 includes an engine 122, a first motor generator 130, a second motor generator 230, and a power split device 124. The output from the engine 122 is split by the power split device 124, which is a planetary gear mechanism, into power for driving the vehicle and power used for generating electricity. The first motor generator 130 normally functions as a generator, and the second motor generator 230 normally functions as a motor. The power from the engine 122, together with the output from the second motor generator 230, rotates drive wheels (not shown) to run the vehicle 120. The second motor generator 230 is a synchronous motor driven by three-phase AC power obtained by boosting the DC power of the battery 58, which is a chargeable and dischargeable secondary battery, by a boost converter 57 and then converting it by an inverter 56. The three-phase AC power generated by the first motor generator 130 is converted to DC power by the inverter 156 and stored in the battery 58.

The first motor generator 130 and the second motor generator 230 each correspond to a rotating electric machine, and their configuration is generally the same as that of the motor 30 in the first embodiment.

The vehicle 120 is provided with an oil supply unit 160 instead of the oil supply unit 60 provided in the vehicle 20 of the first embodiment. The oil supply unit 160 includes an oil pan 162 provided below the engine 122, the first motor generator 130, the power split device 124, and the second motor generator 230, and an oil supply pipe 166 in which an oil pump 164 is disposed. The oil supply unit 160 also includes an oil shower pipe connected to the oil supply pipe 166, although this is omitted in FIG. 6. The oil shower pipe supplies oil to the first motor generator 130 and the second motor generator 230.

Here, unlike the oil pump 64 in the first embodiment, the oil pump 164 is a mechanical pump that is driven by the rotation of the engine 122. The oil pump 164 is driven to rotate by a camshaft (not shown) that is provided in the engine 122.

In such a vehicle 120, oil supply control is executed in the same manner as in the first embodiment. That is, the control based on the flowchart shown in FIG. 4 can also be applied to the second embodiment. However, since the oil pump 164 in this embodiment is mechanical, the engine 122 is started in step S4 in the flowchart shown in FIG. 4. That is, the ECU 70 starts the engine 122 and drives the oil pump 164 by rotating the camshaft of the engine 122. This can improve the insulation resistance in the first motor generator 130 and the second motor generator 230, as in the first embodiment.

In the second embodiment, the oil pump 164 is driven based on the insulation judgment of the insulation judgment unit 70b, so the frequency with which the oil pump operates can be reduced.

If the engine 122 is equipped with an intake pressure sensor, the atmospheric pressure may be estimated based on the detection value of the intake pressure sensor, and this estimated value may be used to determine the insulation of the coil.

Third Embodiment
Next, a third embodiment will be described with reference to Figures 7 to 9. The hardware configuration of a vehicle 220 of the third embodiment is common to the vehicle 120 of the second embodiment, but differs from the second embodiment in that the ECU 70 functions as an applied voltage limiting unit 70d in addition to an information acquiring unit 70a, an insulation determining unit 70b, and a drive instruction unit 70c. Components common to the second embodiment are given the same reference numbers as those in the second embodiment. Detailed descriptions of the components common to the second embodiment are omitted.

The output shaft 122a of the engine 122 equipped in the vehicle 220 is connected to a first motor generator 130, which corresponds to a rotating electric machine. The engine 122 can be started by driving the first motor generator 130.

The first motor generator 130 is driven based on the instruction of the drive instruction unit 70c to start the engine 122. At this time, the applied voltage limiting unit 70d limits the voltage applied to the first motor generator 130.

When the drive instruction unit 70c starts the engine 122 to start driving the mechanical oil pump 164, there is a possibility that dielectric breakdown may occur in the first motor generator 130. If the first motor generator 130 is driven at this time without limiting the applied voltage, dielectric breakdown may occur in the first motor generator 130. Therefore, the applied voltage limiting unit 70d limits the voltage applied to the first motor generator 130.

Now, an example of oil supply control in the third embodiment will be described with reference to the flowchart shown in FIG. 8. Steps S1 to S3 and S7 in the flowchart shown in FIG. 8 are common to the flowchart shown in FIG. 4, that is, the oil supply control in the first embodiment. For this reason, a description of steps S1 to S3 and S7 will be omitted.

In the oil supply control in the third embodiment, the applied voltage limiting unit 70d limits the motor applied voltage in step S31. The limiting of the motor applied voltage is performed based on the map shown in FIG. 9. The map shown in FIG. 9 is a map for setting the output torque. The output torque is expressed as a ratio to the full load torque in the first motor generator 130. The output torque is also called the load factor of the first motor generator 130. The limiting value of the output torque is set by a combination of the coil temperature in the first motor generator 130 and the altitude of the vehicle 220, which are mapped in this map. The higher the altitude at which the vehicle 220 is located and the higher the coil temperature, the greater the limiting of the output torque. The applied voltage limiting unit 70d limits the applied voltage of the first motor generator 130 based on the set limiting value of the output torque. The first motor generator 130 starts the engine 122 by being driven with the limited voltage.

In step S41, which is executed following step S31, the ECU 70 drives the first motor generator 130 and starts the engine 122. The engine 122 starts, which drives the oil pump 164. This starts the supply of oil to the first motor generator 130.

In step S51, the ECU 70 determines whether the oil supply amount is sufficient to avoid insulation breakdown. The oil supply amount can be determined, for example, by a combination of the engine 122 rotation speed and the operation time of the engine 122. If the engine 122 rotation speed is high, the predetermined oil supply amount can be reached even if the operation time is short. Conversely, if the engine 122 rotation speed is low, the operation time until the required oil supply amount is reached will be long. If the ECU 70 makes a negative determination in step S51, it repeats the process of step S51 until it makes a positive determination in step S51. On the other hand, if the ECU 70 makes a positive determination in step S51, it proceeds to step S61.

In step S61, the ECU 70 releases the application voltage limit of the first motor generator 130. This allows the first motor generator 130 to drive the vehicle 220 without being subject to application voltage limits.

After step S61, the ECU 70 proceeds to step S7.

As with the second embodiment, the third embodiment can improve the insulation resistance of the first motor generator 130 and the second motor generator 230. In addition, by limiting the applied voltage when starting the engine 122, insulation breakdown can be more reliably avoided.

Fourth Embodiment
Next, a fourth embodiment will be described with reference to Figures 10 and 11. A rotating electric machine unit 300 of the fourth embodiment includes MG1 and MG2, i.e., a first motor generator 131 and a second motor generator 231. The first motor generator 131 and the second motor generator 231 form a drive device 90 together with a gear mechanism 150. The first motor generator 131, the second motor generator 231 and the gear mechanism 150 are provided in a case 91. The rotating electric machine unit 300 includes components common to the third embodiment. The common components are assigned the same reference numbers as in the third embodiment. A detailed description of the components common to the third embodiment will be omitted.
The configuration of the drive device 90 will be described below, along with an example of oil supply control in the rotating electrical machine unit 300.

The drive unit 90 includes a case 91. Inside the case 91, an input shaft 92, an MG shaft 93, a differential shaft 94, and a countershaft 95 are arranged. The input shaft 92 is coaxially connected to an output shaft of an engine (not shown in the fourth embodiment). Inside the case 91, a first motor generator 131 arranged coaxially with the input shaft 92, and a second motor generator 231 arranged coaxially with the MG shaft 93 are provided.

The MG shaft 93 is an input/output shaft of the second motor generator 231. Torque is transmitted between the input shaft 92 and the MG shaft 93 via a gear 97 of the input shaft 92 and a gear 98 of the MG shaft 93. The rotation of the input shaft 92 is transmitted from the gear 97 of the input shaft 92 to a gear 99 of the counter shaft 95, and is further transmitted from a gear 102 of the counter shaft 95 to a differential ring gear (rotating member) 101 of the differential shaft 94. The rotation of the differential shaft 94 is transmitted to the drive wheels of the vehicle via a differential device (not shown).

In the drive unit 90, the oil scooped up by the differential ring gear 101 is supplied to each part of the drive unit 90, thereby lubricating and cooling each part of the drive unit 90. In addition, insulation breakdown in the first motor generator 131 and the second motor generator 231 is avoided.

An oil reservoir 110 is provided at the bottom of the case 91. An oil catch tank 111 is formed at the top of the case 90. The oil catch tank 111 is provided above the differential ring gear 101. The differential ring gear 101 is provided so that its bottom is located below the liquid level Lv of the oil stored in the oil reservoir 110. When the differential ring gear 101 rotates in conjunction with the vehicle traveling (forward), the differential ring gear 101 scoops up the oil in the oil reservoir 110 and sends it to the oil catch tank 111 as shown by arrow 1a.

The lubricating oil sent to the oil catch tank 111 drips from the oil catch tank 111 toward the first motor generator 131 and the second motor generator 231 as shown by arrow 1b.

This avoids insulation breakdown in the first motor generator 131 and the second motor generator 231.

In this embodiment, a first motor generator 131 and a second motor generator 231 are provided, but the drive device may be a so-called one-motor type in which only one motor generator is provided. Also, in this embodiment, an engine is not essential, and the vehicle may be an electric vehicle.

Now, an example of oil supply control in the fourth embodiment will be described with reference to the flowchart shown in FIG. 11. Steps S1 to S3 and S7 in the flowchart shown in FIG. 11 are common to the flowchart shown in FIG. 4, that is, the oil supply control in the first embodiment. For this reason, a description of steps S1 to S3 and S7 will be omitted.

Comparing the flowchart of this embodiment shown in FIG. 11 with the flowchart of the third embodiment shown in FIG. 8, in this embodiment, steps S32 and S62 are performed instead of steps S31 and S61 in the third embodiment. This is because, while in the third embodiment, only the first motor generator 130 was subject to the applied voltage limit, in this embodiment, both the first motor generator 131 and the second motor generator 231 are subject to the applied voltage limit. The level of the applied voltage in step S32 can be set in the same way as in step S31, so a detailed description thereof will be omitted here.

In this embodiment, there is no process equivalent to step S41 in the third embodiment. In addition, this embodiment and the third embodiment have in common the point that in step S51, it is determined whether the oil supply amount is sufficient. However, in this embodiment, the determination of whether the oil supply amount is sufficient is made based on a combination of the vehicle speed and the duration of that speed.

In the fourth embodiment, oil is supplied by scooping up the oil using gears. For this reason, it is not essential that the system includes an oil pump, and the power consumption and drive loss associated with driving the oil pump are not an issue. However, even in a system that does not include an oil pump, by driving the rotating electric machine by limiting the applied voltage, as in this embodiment, it is possible to avoid dielectric breakdown when the rotating electric machine is driven.

The above embodiments are merely examples for implementing the present invention, and the present invention is not limited to these. Various modifications of these embodiments are within the scope of the present invention. Furthermore, it is self-evident from the above description that various other embodiments are possible within the scope of the present invention.

20 vehicle, 30 motor, 32 rotor, 34 rotor core, 40 stator, 42 stator core, 44 coil, 46 case, 46a oil supply port, 46b oil discharge port, 56 inverter, 57 boost converter, 58 battery, 59 SOC sensor, 60, 160 oil supply unit, 62, 162 oil pan, 64, 164 oil pump, 66 oil supply pipe, 68 oil shower pipe, 70 ECU, 70a information acquisition unit, 70b insulation determination unit, 70c drive instruction unit, 80 ignition, 81 coil temperature sensor, 82 oil temperature sensor, 83 atmospheric pressure sensor, 84 GPS altitude information acquisition unit, 85 voltage sensor, 100, 200, 300 rotating electrical unit

Claims (6)

A control device for a rotating electric machine unit including a rotating electric machine and an oil supply unit including an oil pump that supplies oil to a coil included in the rotating electric machine,
an information acquiring unit that acquires information regarding an air density in a coil and information regarding a voltage applied to the rotating electric machine;
an insulation determination unit that determines whether or not insulation breakdown will occur in the coil based on the information about the air density and the information about the voltage acquired by the information acquisition unit;
a drive instruction unit that drives the oil supply unit when the insulation determination unit determines that insulation breakdown will occur in the coil and that it is necessary to maintain an insulation state by supplying oil; and
Equipped with
A control device for a rotating electrical unit. The information acquisition unit acquires, as the information on the air density, information on the air temperature inside the coil and information on the atmospheric pressure.
The control device for a rotating electrical machine unit according to claim 1 . The information acquisition unit acquires a detected value of the temperature of the coil or a detected value of the temperature of the oil as information regarding the air temperature in the coil.
The control device for a rotating electrical machine unit according to claim 2 . The information acquisition unit acquires, as the information related to the atmospheric pressure, a detection value of an atmospheric pressure sensor or altitude information acquired by a position information acquisition device provided in a vehicle on which the rotating electric machine is mounted.
The control device for a rotating electrical machine unit according to claim 2 . The oil pump is a mechanical pump that is driven by operation of an internal combustion engine,
the drive instruction unit drives the rotating electric machine to start the internal combustion engine when the insulation determination unit determines that insulation breakdown will occur in the coil and that it is necessary to maintain an insulation state by supplying oil,
The electric power generating device further includes an applied voltage limiting unit that limits a voltage applied to the electric rotating machine when the electric rotating machine is driven to start the internal combustion engine based on an instruction from the drive instruction unit.
The control device for a rotating electrical machine unit according to claim 1 . A control device for a rotating electric machine unit, comprising: a rotating electric machine; and an oil supply unit that is driven by the rotating electric machine and includes a gear mechanism at least a portion of which is immersed in oil, and supplies the oil to a coil included in the rotating electric machine by operating the gear mechanism,
an information acquisition unit that acquires information regarding an air density in a coil and information regarding a voltage applied to the rotating electric machine;
an insulation determination unit that determines whether or not insulation breakdown will occur in the coil based on the information about the air density and the information about the voltage acquired by the information acquisition unit;
a drive instruction unit that drives the rotating electric machine when the insulation determination unit determines that insulation breakdown will occur in the coil and that it is necessary to maintain an insulation state by supplying oil; and
an applied voltage limiting unit that limits a voltage applied to the rotating electric machine when the rotating electric machine is driven in response to an instruction from the drive instruction unit;
Equipped with
A control device for a rotating electrical unit.

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