JP2014034220A - Motor control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a motor control device capable of controlling heat quantity generated from a motor on the basis of a temperature rise request of a temperature rise object.SOLUTION: A motor control device is applied to a vehicle including a MG 30, a transmission 40 changing a transmission ratio to be a ratio of rotational speed of the MG 30 to rotational speed of a drive wheel 70, and a heat medium circulation circuit 60 transmitting heat between the MG 30 and a temperature rise object 10. The motor control device performs transmission control changing the transmission ratio of the transmission 40 and the rotational speed of the MG 30 so as to lower efficiency of the MG 30 in a state in which speed of the vehicle is maintained on the basis of a temperature rise request value of the temperature rise object 10. The motor control device performs the transmission control so as to lower efficiency of the MG 20 as the temperature rise request value becomes larger, and performs the transmission control so as to improve the efficiency of the MG 30 as the temperature rise value becomes smaller.

Description

  The present invention relates to a control device for a vehicle drive motor.

  It has been proposed to heat a temperature increase target mounted on a vehicle using heat generated from a traveling motor. For example, Patent Document 1 proposes heating a battery that is a target of temperature increase using exhaust heat of a motor.

JP 2010-228686 A

  However, in Patent Document 1, the amount of heat generated from the motor cannot be controlled even if the temperature increase request for temperature increase is changed.

  An object of this invention is to provide the motor control apparatus which can control the calorie | heat amount which generate | occur | produces from a motor based on the temperature rising request | requirement of temperature rising object.

  In order to solve the above-mentioned problems, the invention described in claim 1 is directed to a traveling motor, a transmission that changes a gear ratio that is a ratio of the rotational speed of the motor and the rotational speed of the drive wheels, and the motor. Applied to a vehicle having a heat transfer path for transferring heat to and from the temperature target, and reducing the efficiency of the motor while maintaining the speed of the vehicle based on the temperature increase request value of the temperature increase target Shift control is performed to change the transmission ratio of the transmission and the rotational speed of the motor so that the transmission is performed.

  The efficiency of the motor changes according to the rotational speed of the motor. When the efficiency of the motor is reduced, the loss of the motor, that is, the amount of heat generated from the motor increases.

  According to the first aspect of the present invention, the transmission gear ratio and the motor rotation speed are set so as to lower the motor efficiency while maintaining the vehicle speed based on the temperature increase request value to be increased. Be changed. That is, the rotational speed of the motor is changed so that the amount of heat generated by the motor increases based on the temperature increase required by the temperature increase target. And the heat which generate | occur | produces from a motor is transmitted to the temperature rising object by a heat transfer path, and raises the temperature of temperature rising object. Therefore, according to the first aspect of the present invention, the heat generation amount of the motor is controlled in a state where the speed of the vehicle is maintained in accordance with the temperature increase request value of the temperature increase target, and the temperature of the temperature increase target is increased. Can do.

The schematic diagram which shows the structure of the vehicle system which concerns on 1st Embodiment. Motor performance curve showing the relationship between motor rotation speed and efficiency. The figure which shows the relationship between the rotational speed of a motor, and the temperature rise of a battery. The figure which shows the relationship between the rotational speed of a motor, and vehicle speed. The schematic diagram which shows the battery temperature rising state of the vehicle system which concerns on 2nd Embodiment. The schematic diagram which shows the battery cooling state of the vehicle system which concerns on 2nd Embodiment. The schematic diagram which shows the inverter and MG cooling state of the vehicle system which concern on 2nd Embodiment. The schematic diagram which shows the structure of the vehicle system which concerns on other embodiment. The schematic diagram which shows the structure of the vehicle system which concerns on other embodiment.

  Hereinafter, embodiments embodying a motor control device applied to an electric vehicle will be described with reference to the drawings. In the following embodiments, portions that are the same or equivalent to each other are denoted by the same reference numerals in the drawings, and the description of the portions with the same reference numerals is incorporated. The motor control device may be applied not only to electric vehicles but also to hybrid vehicles.

(First embodiment)
The configuration of the vehicle system according to the first embodiment will be described with reference to FIG. The vehicle system includes an MG 30 (motor), an inverter 20, a battery 10, a transmission 40, an ECU 50 (motor control device), a differential 80, drive wheels 70, a heat medium circulation circuit 60 (heat transfer path). ). This vehicle system is a system in which the power of the MG 30 is transmitted to the drive wheels 70 via the transmission 40 and the differential 80, and the drive wheels 70 are driven by the power of the MG 30.

  The MG 30 is composed of one or more motor generators that operate as an electric motor and a generator. As the MG 30, for example, an alternator that does not use a rare earth can be employed. MG 30 receives power supply from battery 10 via inverter 20. The MG 30 receiving the power supply operates as an electric motor and generates a driving force for driving the vehicle.

  The inverter 20 is a power conversion circuit that performs DCAC conversion, and operates the MG 30 as an electric motor based on a control signal transmitted from the ECU 50 described later.

  The battery 10 supplies power to the MG 30 via the inverter 20 and receives power supplied from the MG 30 by regenerative power generation. If the battery 10 is not used in an appropriate temperature range, the operation efficiency deteriorates. Therefore, a temperature sensor 11 for temperature management is provided. The battery 10 also includes a current sensor for managing the remaining capacity. Detection values detected by the temperature sensor 11 and other sensors included in the battery 10 are transmitted to the ECU 50.

  The transmission 40 has an input shaft connected to the output shaft of the motor 30 and an output shaft connected to the input shaft of the differential 80. The transmission 40 changes a gear ratio that is a ratio between the rotational speed Nm of the MG 30 and the rotational speed of the drive wheels 70. Therefore, by changing the gear ratio of the transmission 40, the rotational speed Nm of the MG 30 can be changed while maintaining the vehicle speed. As the transmission 40, for example, an IVT (Infinity Variable Transmission) including a CVT (Continuously Variable Transmission) and a planetary gear can be employed. When IVT is adopted, a torque converter becomes unnecessary.

  The differential 80 has an input shaft connected to the output shaft of the transmission 40, and divides the power of the MG 30 and transmits it to the two drive wheels 70.

  The heat medium circulation circuit 60 is a circuit that circulates the heat medium 61 between the MG 30 and the battery 10. The heat medium 61 is cooling water or the like. The heat medium circulation circuit 60 includes a pump 62 between the MG 30 and the battery 10. The pump 62 circulates the heat medium 61 in the direction indicated by the arrow along the normal path from the pump 62 to the MG 30, from the MG 30 to the battery 10, and from the battery 10 to the pump 62.

  The ECU 50 is configured as a microcomputer including a ROM storing various control programs, a RAM storing various data, and a CPU. The ECU 50 sequentially acquires detection values detected by the temperature sensor 11 and other various sensors. Then, the ECU 50 transmits a control signal to the inverter 20, the transmission 40, and the like based on the acquired various detection values, and performs shift control for changing the transmission gear ratio of the transmission 40 and the rotational speed Nm of the MG 30.

  Next, the relationship between the rotational speed Nm of MG3 and the temperature increase of the temperature increase target will be described with reference to FIGS. The curve shown in FIG. 2 is a performance curve of MG30 showing the relationship between the rotational speed Nm of MG30 and the efficiency η. The efficiency η is expressed by (rotational speed Nm × torque T−loss) / input power. That is, the loss is large when the efficiency η is low, and the loss is small when the efficiency η is high. The loss of MG30 is copper loss, iron loss, mechanical loss, and the like, and is the amount of heat generated by MG30. Therefore, when the efficiency η is low, the amount of heat generated from the MG 30 increases. The efficiency η changes according to the rotational speed Nm. That is, the amount of heat generated from the MG 30 can be controlled by changing the rotation speed Nm.

  As shown in FIG. 2, the performance curve of MG30 is an upwardly convex curve. Therefore, even if the rotational speed Nm is increased or decreased from the rotational speed Nm of A at which the efficiency η is maximized, the efficiency η is decreased. In particular, when the rotational speed Nm is decreased, the efficiency η decreases rapidly as the rotational speed Nm decreases.

  When a temperature increase request is generated, the ECU 50 changes the rotational speed Nm so as to reduce the efficiency η in order to increase the amount of heat generated from the MG 30. On the other hand, when there is no temperature increase request, ECU 50 drives MG 30 at the rotational speed in rotational speed region H with high efficiency η.

  FIG. 3 shows a battery 10 that is to be heated by rotating the MG 30 at each of the rotational speeds Nm of A, B, and C on the performance curve shown in FIG. The temperature rise rate of the battery 10 when the is heated is shown. When the MG 30 is rotated at the rotational speed Nm of C having the lowest efficiency η, the amount of heat generated from the MG 30 is the largest, so the speed at which the temperature of the battery 10 rises is the fastest. On the other hand, when the MG 30 is rotated at the rotational speed Nm of A with the highest efficiency η, the amount of heat generated from the MG 30 is the smallest, so the speed at which the temperature of the battery 10 rises is the slowest. Therefore, if the heat generation amount is controlled according to the temperature increase request value of the battery 10, the battery 10 can be rapidly heated. The temperature increase request value is a temperature increase range required for the battery 10 or a target temperature of the battery 10.

  Next, the relationship between the rotational speed of MG30 and the vehicle speed will be described. FIG. 4 shows the relationship between the rotational speed Nm of the MG 30 and the vehicle speed when the vehicle speed is changed from 0 to 120 km / h. The straight line indicates the relationship between the vehicle speed and the rotational speed Nm when the speed ratio, which is the ratio between the rotational speed of the MG 30 and the rotational speed of the drive wheel 70, is maximized. In the present embodiment, the transmission 40 and the differential 80 are designed so that the gear ratio is 0 to the maximum value. Note that the range of the gear ratio can be changed by design.

  A region surrounded by a broken line in FIG. 4 is a region where the gear ratio is 0 to the maximum value. That is, a region surrounded by a broken line is a rotational speed region S of the MG 30 that can be selected for a vehicle speed of 0 to 120 km / h. In the figure, the selectable rotation speed region S is up to 4000 rpm, but in practice it is up to an upper limit determined by design. In the selectable rotation speed area S, the rotation speed area where the rotation speed Nm is 2000 to 3000 rpm is the rotation speed area H with high efficiency η. If the vehicle speed is 0 to 120 km / h, the rotational speed Nm can be selected from the rotational speed region H with high efficiency η. That is, when the vehicle speed is 0 to 120 km / h, the MG 30 can be driven at a rotational speed Nm with a high efficiency η by changing the gear ratio of the transmission 40.

  For example, when the vehicle speed is 20 km / h, the rotational speed Nm can be selected between 500 rpm and the upper limit value by changing the gear ratio of the transmission 40. Furthermore, when the vehicle speed is 40 km / h, the rotation speed can be selected between 1000 rpm and an upper limit value. Therefore, based on the temperature increase request value for the temperature increase target, the shift control for changing the speed ratio and the rotation speed Nm can be performed while the vehicle speed is maintained, and the efficiency η can be reduced.

  Next, a description will be given of the shift control performed by the ECU 50 during travel of the vehicle when the temperature increase target is the battery 10 with reference to FIG. If the battery 10 is not used in an appropriate temperature range, the operation efficiency deteriorates. Therefore, when the temperature of the battery 10 is lower than the appropriate temperature, it is necessary to raise the temperature of the battery 10. If the temperature increase target is the battery 10, the temperature of the battery 10 can be raised while the vehicle is traveling by the heat generated from the MG 30.

  The ECU 50 sequentially acquires the temperature of the battery 10 detected by the temperature sensor 11. Then, the ECU 50 changes the gear ratio and the rotational speed Nm of the transmission 40 so as to reduce the efficiency η while maintaining the vehicle speed based on the temperature increase request value of the battery 10. Specifically, the gear ratio and the rotational speed Nm are changed so that the efficiency η decreases as the temperature increase request value of the battery 10 increases.

  Here, a predetermined rotational speed that is lower than the rotational speed Nm at which the efficiency η is maximum is taken as the first rotational speed. When the rotational speed Nm at the time when the temperature increase request is generated is lower than the first rotational speed, the speed change control is performed by decreasing the rotational speed Nm instead of increasing the rotational speed Nm.

  When the rotational speed Nm is lower than the first rotational speed, if the efficiency η is decreased by increasing the rotational speed Nm, the speed ratio and the rotational speed Nm fluctuate, so the rotational speed of the drive wheel 70 varies. It becomes easy to do. On the other hand, when the rotational speed Nm is lower than the first rotational speed, if the efficiency η is reduced by reducing the rotational speed Nm, fluctuations in the gear ratio and the rotational speed Nm are reduced. Variations can be suppressed.

  Further, a predetermined rotational speed higher than the rotational speed Nm at which the efficiency η is maximized is set as the second rotational speed. When the rotational speed Nm at the time when the temperature increase request is generated is higher than the second rotational speed, the speed change control is performed by increasing the rotational speed Nm instead of decreasing the rotational speed Nm.

  When the rotational speed Nm is higher than the second rotational speed, if the efficiency η is reduced by reducing the rotational speed Nm, the speed ratio and the rotational speed Nm fluctuate, so the rotational speed of the drive wheels 70 fluctuates. It becomes easy. On the other hand, when the rotational speed Nm is higher than the second rotational speed, if the efficiency η is decreased by increasing the rotational speed Nm, the change in the gear ratio and the rotational speed Nm becomes smaller. Fluctuations can be suppressed.

  However, when the temperature of the battery 10 is lower than a predetermined value, the shift control is performed by reducing the rotational speed Nm below the rotational speed Nm at which the efficiency η is maximized regardless of the rotational speed Nm at the time when the temperature increase request is generated. I do. Here, the predetermined value is a value that is significantly lower than the appropriate temperature of the battery 10 (for example, 10 ° C. to 40 ° C.), for example, −10 ° C. In addition, there exists a possibility that the battery liquid of the battery 10 may freeze at -20 degrees C or less.

  In an environment where the temperature of the battery 10 is significantly lower than the appropriate temperature, the road surface is frozen and the vehicle speed is reduced. When the vehicle speed is low, it is desirable to reduce the rotational speed Nm.

  Subsequently, the ECU 50 operates the pump 62. When the pump 62 is operated, the heat medium 61 that stores the amount of heat generated from the MG 30 circulates in the heat medium circuit 60 from the MG 30 toward the battery 10. Therefore, the heat stored in the heat medium 61 is transmitted to the battery 10 and the battery 10 is heated.

  Next, the ECU 50 performs shift control so as to improve the efficiency η as the temperature of the battery 10 rises and the temperature increase request value of the battery 10 decreases. Specifically, the shift control is performed so that the rotation speed Nm approaches the rotation speed Nm at which the efficiency η is maximized.

  Furthermore, when the temperature of battery 10 falls within the appropriate temperature range, ECU 50 drives MG 30 in rotation speed region H where efficiency η is high. Then, the ECU 50 stops the operation of the pump 62 and stops the circulation of the heat medium 61.

  The first embodiment described above has the following effects.

  Based on the temperature increase request value of the battery 10, the gear ratio of the transmission 40 and the rotational speed Nm of the MG 30 are changed so as to reduce the efficiency η while maintaining the vehicle speed. That is, the rotational speed Nm of the MG 30 is changed so that the amount of heat generated by the MG 30 is increased based on the temperature increase required by the battery 10. Then, the heat generated from the MG 30 is transmitted to the battery 10 by the heat medium circulation circuit 60 and raises the temperature of the battery 10. Therefore, the amount of heat generated by MG 30 can be controlled in accordance with the temperature increase request value of battery 10 while maintaining the vehicle speed, and the temperature of battery 10 can be increased.

  -The amount of heat generated from the MG 30 increases as the required temperature increase value of the battery 10 increases. Therefore, the temperature increase target temperature can be increased by using more heat as the temperature increase range required by the battery 10 is larger. Then, as the temperature of the battery 10 rises and the temperature increase request value becomes smaller, the rotation speed Nm is changed so as to improve the efficiency η. Therefore, the efficiency η can be increased as the amount of heat necessary for increasing the temperature of the battery 10 decreases.

  -When the rotational speed Nm is lower than the first rotational speed, if the speed change control is performed by reducing the rotational speed Nm, fluctuations in the gear ratio and the rotational speed Nm, and consequently fluctuations in the rotational speed of the drive wheels 70 are suppressed. Is done. Therefore, it can suppress giving a torque shock to a driver | operator, and drivability can be improved. In addition, when the rotational speed Nm is higher than the second rotational speed, drivability can be similarly improved by performing the shift control by increasing the rotational speed Nm.

  Even if the rotational speed Nm is increased or decreased from the rotational speed Nm at which the efficiency η is maximized, the efficiency η is decreased. However, the efficiency η can be further reduced by lowering the rotational speed Nm than by increasing it. That is, when the temperature of the battery 10 is lower than a predetermined value, the amount of heat generated by the MG 30 can be increased.

  In an environment where the temperature of the battery 10 is lower than a predetermined value, the vehicle speed is often small due to freezing of the road surface or the like. If the rotational speed Nm is reduced when the vehicle speed is low, the vehicle speed and the rotational speed Nm can be combined in a desirable manner.

  Since the battery 10 is heated while the vehicle is running, it is not necessary to wait for the vehicle to start until the battery 10 is heated.

(Second Embodiment)
The configuration of the vehicle system according to the second embodiment will be described with reference to FIG. In the second embodiment, the inverter 20 is thermally connected to the heat medium circulation circuit 60 on the downstream side of the pump 62 and the upstream side of the MG 30.

  In addition, a heat exchanger 64 for cooling the heat medium 61 is connected to the heat medium circulation circuit 60 on the downstream side of the MG 30 and the upstream side of the battery 10. Furthermore, a first bypass 65 that bypasses the heat exchanger 64, a second bypass 66 that bypasses the battery 10, and a switching valve 63 are connected to both ends of each bypass path in the heat medium circulation circuit 60. ing. The switching valves 63 connected to both ends of the first bypass 65 switch the circulation of the heat medium 61 between the heat exchanger 64 and the first bypass 65. Further, the switching valves 63 connected to both ends of the second bypass circuit 66 switch the circulation of the heat medium 61 between the battery 10 and the second bypass circuit 66.

  The ECU 50 circulates the heat medium 61 to the first bypass 65 and the battery 10 as shown in FIG. 5 when performing the shift control so as to reduce the efficiency η based on the temperature increase request value of the battery 10. As described above, the four switching valves 63 are switched to operate the pump 62.

  Then, the heat medium 61 absorbs heat generated from the inverter 20 and the MG 30, and then circulates to the battery 10 through the first bypass 65. As a result, the temperature of the battery 10 is raised by the heat stored in the heat medium 61.

  Next, FIG. 6 shows a heat medium circulation circuit 60 when the battery 10 is cooled. As the battery 10 is repeatedly charged and discharged, Joule loss due to the internal resistance of the battery 10 occurs, and the temperature of the battery 10 rises. When the battery 10 is used at a temperature exceeding an appropriate temperature range, the progress of deterioration becomes remarkable. Therefore, when the temperature of the battery 10 is higher than the appropriate temperature, it is necessary to cool it.

  When the temperature of the battery 10 is higher than the appropriate temperature, the ECU 50 switches the four switching valves 63 and operates the pump 62 so that the heat medium 61 is circulated to the heat exchanger 64 and the battery 10. In this case, the ECU 50 performs shift control so that the MG 30 is driven in a rotation speed region where the efficiency η is high.

  Then, the heat medium 61 passes through the heat exchanger 64 after absorbing the heat of the battery 10, the inverter 20, and the MG 30. After being cooled by the heat exchanger 64, the heat medium 61 is circulated again to the battery 10, the inverter 20, and the MG 30, and absorbs the heat of the battery 10, the inverter 20, and the MG 30. Therefore, battery 10 is cooled together with inverter 20 and MG 30.

  Further, FIG. 7 shows a heat medium circulation circuit 60 when only the inverter 20 and the MG 30 are cooled. When the temperature of the battery 10 is in an appropriate temperature range, it is not necessary to heat or cool the battery 10.

  In such a case, the ECU 50 switches the four switching valves 63 and operates the pump 62 so that the heat medium 61 is circulated through the heat exchanger 64 and the second bypass circuit 66. In this case, the ECU 50 performs shift control so that the MG 30 is driven in a rotation speed region where the efficiency η is high.

  Then, the heat medium 61 is cooled by the heat exchanger 64 after absorbing the heat of the inverter 20 and the MG 30. Thereafter, the heat medium 61 is transmitted to the inverter 20 and the MG 30 again. Therefore, when the temperature of the battery 10 is in an appropriate temperature range, only the inverter 20 and the MG 30 can be cooled.

  The second embodiment described above has the same effects as the first embodiment, and further has the following effects.

  -Since the temperature of the battery 10 is raised using not only the MG 30 but also the heat of the inverter 20, the temperature of the battery 10 can be quickly raised.

  When the switching valve 63 is switched so that the heat medium 61 is circulated between the first bypass 65 and the battery 10, the battery 10 is heated. Further, when the switching valve 63 is switched so that the heat medium 61 is circulated between the heat exchanger 64 and the battery 10, the battery 10 is cooled. Therefore, not only the temperature of the battery 10 but also the cooling can be performed using the heat medium circulation circuit 60.

(Other embodiments)
-In 2nd Embodiment, although the inverter 20 was thermally connected to the heat-medium circulation circuit 60, as shown in FIG. 8, even if the inverter 20 is not thermally connected to the heat-medium circulation circuit 60, Good.

  Even if the inverter 20 is not thermally connected to the heat medium circulation circuit 60, when the temperature of the battery 10 is lower than the appropriate temperature, the battery 10 can be heated using the heat generated by the MG 30. Further, when the temperature of the battery 10 is higher than the appropriate temperature, the battery 10 can be cooled together with the MG 30. Furthermore, when the temperature of the battery 10 is within an appropriate range, only the MG 30 can be cooled.

  In the second embodiment, the battery 10 and the inverter 20 and the MG 30 are thermally connected by the single heat medium circulation circuit 60. However, the heat medium circulation circuit that circulates the heat medium in the inverter 20 and the MG 30 and the heat medium circulation circuit that circulates the heat medium in the battery 10 may be thermally connected by a heat exchanger.

  In FIG. 9, a first heat medium circulation circuit 60 that circulates the heat medium 61 in the inverter 20 and the MG 30 and a second heat medium circulation circuit 90 that circulates the heat medium 91 in the battery 10 are represented by the second heat exchanger 94. 1 shows the configuration of a thermally connected vehicle system.

  When the temperature of the battery 10 is lower than the appropriate temperature, the switching valve 63 is switched so that the heat medium 61 is circulated to the first bypass 65 and the pump 62 and the pump 92 are operated. Then, in the first heat medium circulation circuit 60, the heat medium 61 absorbs the heat of the inverter 20 and the MG 30, passes through the first bypass 65, and is circulated to the second heat exchanger 94. In the second heat exchanger 94, the heat stored in the heat medium 61 is transmitted to the heat medium 91. In the second heat medium circulation circuit 90, the heat medium 91 that stores heat is circulated to the battery 10, and the battery 10 is heated.

  When the temperature of the battery 10 is higher than the appropriate temperature, the switching valve 63 is switched so that the heat medium 61 is circulated to the first heat exchanger 64, and the pump 62 and the pump 92 are operated. Then, in the first heat medium circulation circuit 60, the heat medium 61 absorbs the heat of the inverter 20 and the MG 30, is then cooled by the first heat exchanger 64, and is circulated to the second heat exchanger 94. On the other hand, in the second heat medium circulation circuit 90, the heat medium 91 absorbs the heat of the battery 10, is then circulated to the second heat exchanger 94, and is cooled by the heat medium 61. Thereafter, the heat medium 91 is circulated again to the battery 10 to cool the battery 10.

  Therefore, even with the configuration shown in FIG. 9, the battery 10 can be heated and cooled. In addition, when the temperature of the battery 10 is in an appropriate temperature range, the pump 92 is stopped and the circulation of the heat medium 91 is stopped.

  In each of the above embodiments, the shift control is performed while the vehicle is running, but the connection between the MG 30 and the drive wheel 70 may be disconnected and the shift control may be performed while the vehicle is stopped.

  The MG 30 and the drive wheel 70 are connected via the transmission 40. The connection between the MG 30 and the drive wheel 70 is disconnected by releasing the connection between the MG 30 and the transmission 40, the connection between the drive wheel 70 and the transmission 40, or the clutch connection in the transmission 40. . By disconnecting the connection between the MG 30 and the drive wheel 70, the power of the MG 30 is not transmitted to the drive wheel 70. Therefore, MG30 can be used as a heat source for heating the temperature increase target while the vehicle is stopped.

  In each of the above embodiments, the temperature increase target is the battery 10, but the temperature increase target is not limited to the battery 10. For example, a heater core, an electric heating sheet, or the like may be targeted for temperature increase.

  DESCRIPTION OF SYMBOLS 20 ... Inverter, 30 ... MG (motor), 40 ... Transmission, 50 ... ECU (motor control apparatus), 60 ... Heat-medium circulation circuit (heat transfer path), 70 ... Drive wheel.

Claims (9)

A traveling motor (30), a transmission (40) that changes a transmission ratio that is a ratio of a rotational speed of the motor and a rotational speed of the drive wheel (70), and the motor and a temperature increase target (10) And a heat transfer path (60) for transferring heat between the vehicle,
Shift control for changing the speed ratio of the transmission and the rotational speed of the motor so as to reduce the efficiency of the motor while maintaining the speed of the vehicle based on the temperature increase request value of the temperature increase target A motor control device (50) characterized in that While performing the shift control so as to decrease the efficiency of the motor as the temperature increase request value is larger,
The motor control device according to claim 1, wherein the shift control is performed so as to improve the efficiency of the motor as the required temperature increase value decreases.   3. The motor control device according to claim 1, wherein when the rotation speed of the motor is lower than the first rotation speed, the shift control is performed by reducing the rotation speed of the motor.   4. The motor control according to claim 3, wherein when the rotation speed of the motor is higher than a second rotation speed set higher than the first rotation speed, the shift control is performed by increasing the rotation speed of the motor. apparatus. The vehicle includes a battery that exchanges power with the motor,
The motor control device according to claim 1, wherein the temperature increase target is the battery.   The motor control device according to claim 5, wherein when the temperature of the battery is lower than a predetermined value, the shift control is performed by reducing a rotation speed of the motor. The heat transfer path is a circuit for circulating the heat medium (61),
In the heat transfer path, a heat exchanger (64) for cooling the heat medium, a detour (65) for detouring the heat exchanger, circulation of the heat medium, the heat exchanger and the detour A switching valve (63) for switching to
The motor control device according to claim 5, wherein when the temperature of the battery is higher than an appropriate temperature, the switching valve is switched so that the heat medium is circulated through the heat exchanger.   The motor control apparatus according to claim 1, wherein the shift control is performed while the vehicle is traveling. Disconnect the connection between the motor and the drive wheel,
The motor control apparatus according to claim 1, wherein the shift control is performed while the vehicle is stopped.

Images