WO2012131953A1

WO2012131953A1 - In-wheel motor vehicle

Info

Publication number: WO2012131953A1
Application number: PCT/JP2011/058114
Authority: WO
Inventors: 監介吉末
Original assignee: トヨタ自動車株式会社
Priority date: 2011-03-30
Filing date: 2011-03-30
Publication date: 2012-10-04
Also published as: JPWO2012131953A1; JP5590221B2

Abstract

Provided is an in-wheel motor vehicle which improves on the installability of a motor without reducing the output torque demanded by the vehicle. In an in-wheel motor vehicle which has a plurality of drive-use electric motors inside a wheel, the plurality of drive-use electric motors at least comprises a first electric motor (5) disposed coaxially with the rotational shaft of the wheel, and second electric motors (6,7,8) which are disposed at the same position in the axial direction of the wheel as the first electric motor (5). A planetary gear mechanism (9) comprising a sun gear (9S) connected to the output shaft of the first electric motor (5), and a ring gear (9R) to which power from the second electric motors (6,7,8) is transmitted is disposed inside the wheel.

Description

In-wheel motor car

The present invention relates to an in-wheel motor vehicle configured to obtain a driving force of a vehicle by providing a motor inside a wheel of a driving wheel.

An electric vehicle using an electric motor as a power source has been developed instead of a vehicle using an internal combustion engine as a power source. Among the electric vehicles, a vehicle using a so-called in-wheel motor, in which a motor is mounted in each wheel or in the front wheel or the rear wheel, has been developed. The in-wheel motor is capable of outputting a high torque to obtain the driving force of the vehicle, that is, a large motor is required, while the space for mounting the motor is limited to the inside of the wheel. There is a limit to the torque that can be output. In addition, by outputting a high torque, the amount of heat generated due to electrical resistance or the like becomes high, and the motor characteristics or durability may be reduced.

Japanese Patent Application Laid-Open No. 2008-44434 describes an in-wheel motor in which a motor is mounted on a wheel provided with a ball joint and a brake caliper that are connected to a wheel side end of a tie rod. This in-wheel motor is mounted with a motor offset in the radial direction from the rotation center of the wheel, and a counter gear is provided on the output shaft of the motor in order to match the rotation axis of the motor with the rotation axis of the wheel. A shaft is connected to a gear that meshes with the counter gear and the other end is connected to a sun gear constituting a planetary gear mechanism.

Japanese Patent Application Laid-Open No. 2007-269209 describes an in-wheel motor in which a motor is provided coaxially with the rotating shaft of a wheel and another motor is provided at a position offset from the motor in the axial direction and the radial direction. Yes. This in-wheel motor is configured so that the vertical movement of the vehicle body can be damped by rotating the motor and the other motor in the opposite direction. Therefore, there is no need to provide a shock absorber and the degree of freedom in design is increased. It can be improved.

Further, Japanese Patent Laid-Open No. 2010-280295 discloses a tire so that a power transmission path between the motor and the tire can be connected and disconnected in order to drive the motor in an operation region where the motor efficiency is good. A first centrifugal clutch that transmits power when the motor rotates below a predetermined rotational speed, a second centrifugal clutch that transmits power when the motor rotates at a predetermined rotational speed or more, and a one-way that transmits tire torque to the motor An in-wheel motor with a clutch is described.

Furthermore, Japanese Patent Application Laid-Open Nos. 2009-154723 and 2008-125329 disclose the output of the motor according to the storage capacity (SOC) of the power storage device connected to the motor, the temperature of the power storage device, or the temperature of the motor. An apparatus for limiting the amount of regeneration is described. Japanese Patent Application Laid-Open Nos. 2010-243327 and 2004-324613 describe a device that reads a planned travel route by a navigation device and predicts a heat generation amount of a battery or a motor from the planned travel route, In particular, the device described in Japanese Patent Application Laid-Open No. 2004-324613 is configured to limit the motor output in advance or increase the cooling amount based on the predicted heat generation amount of the motor.

As described above, since an in-wheel motor has a motor and a gear train mounted inside the wheel, it is difficult to mount a large motor capable of outputting high torque. For this reason, the in-wheel motor described in Japanese Patent Application Laid-Open No. 2008-44434 increases the output torque by increasing the motor diameter by shifting the wheel rotation shaft and the motor rotation shaft by providing a counter gear. The in-wheel motor described in Japanese Patent Application Laid-Open No. 2007-269209 is provided with a motor on the same axis as the rotation axis of the wheel, and other than the position offset from the motor in the axial direction and the radial direction. By providing this motor, the two motors are configured to obtain the output torque required for the vehicle. However, when the motor is offset in the radial direction as described in Japanese Patent Application Laid-Open Nos. 2008-44434 and 2007-269209, a gear train for offsetting the rotation shaft is provided. A space in the axial direction to be mounted is required.

The present invention has been made paying attention to the above technical problem, and provides an in-wheel motor vehicle capable of improving the mountability of the motor without reducing the output torque required for the vehicle. It is the purpose.

In order to achieve the above object, the present invention provides an in-wheel motor vehicle having a plurality of drive motors inside a wheel, wherein the plurality of drive motors are provided coaxially with a rotation shaft of the wheel. A first gear and at least a second motor disposed at the same position as the first motor in the axial direction of the wheel, and a sun gear connected to the output shaft of the first motor; A planetary gear mechanism having a ring gear to which the power of the electric motor is transmitted is provided inside the wheel.

Further, the present invention provides the in-wheel motor vehicle according to the above-described invention, wherein a one-way clutch that transmits power when the second electric motor is driven in a direction in which the vehicle travels forward is provided on the ring gear. It is.

Furthermore, the present invention is the in-wheel motor vehicle according to the above invention, wherein a plurality of teeth meshing with a gear connected to an output shaft of the second electric motor are formed on the outer peripheral surface of the ring gear. is there.

Furthermore, the present invention further includes an electronic control device that controls electric power supplied to each of the first electric motor and the second electric motor, and the electronic control device is based on the required torque output from the wheel. Torque calculation means for calculating output torques of the first motor and the second motor, and rotation speed calculation means for calculating the rotation speed of each motor based on the torque of each motor calculated by the torque calculation means. It is an in-wheel motor vehicle characterized by having.

Furthermore, in the present invention according to the present invention, the rotational speed calculation means further includes means for changing the rotational speed of each electric motor based on the state of each electric motor. It is a wheel motor car.

Furthermore, the present invention is the in-wheel motor vehicle according to the above invention, wherein the state of each electric motor includes a temperature state of each electric motor.

Furthermore, according to the present invention, in the above invention, the temperature state of each electric motor is determined by comparing a predetermined temperature based on a temperature that restricts driving of each electric motor with the temperature of each electric motor, and When the temperature of any one of the first electric motor and the second electric motor is higher than the predetermined temperature, the calculating means sets the rotational speed of the motor having a temperature higher than the predetermined temperature as the rotational speed with a small power loss. The in-wheel motor vehicle further comprises means for rotating the rotation speed of the other motor so as to compensate for a decrease in the rotation speed of the motor whose temperature is higher than the predetermined temperature.

Furthermore, the present invention further includes a control device that controls electric power supplied to each electric motor in each of the electric motors according to the above-described invention, wherein the rotation speed calculation means is based on the temperature of the control device. The in-wheel motor vehicle further includes means for changing the rotational speed of each electric motor.

Furthermore, the present invention further includes a power storage device that supplies electric power to each electric motor or charges electric power generated by each electric motor in the above-described invention, wherein the rotation speed calculation means is in a charged state of the electric power storage device. Accordingly, the in-wheel motor vehicle further comprises means for calculating the rotational speed of each electric motor.

Furthermore, the present invention further includes a navigation device that presents a travel route on which the vehicle travels in the above-described invention, and the electronic control device is configured to provide each motor when traveling on the travel route presented by the navigation device. An in-wheel motor vehicle comprising: means for predicting a heat generation amount; and means for calculating the rotation speed of each electric motor based on the predicted heat generation amount of each electric motor.

According to this invention, at least both of the first electric motor provided coaxially with the rotating shaft of the wheel inside the wheel and the second electric motor arranged at the same position as the first electric motor in the axial direction of the wheel. A planetary gear mechanism having a sun gear connected to the first motor and a ring gear connected to the second motor is provided inside the wheel. Therefore, each electric motor can be arranged in the axial direction of the wheel without providing a gear or the like for aligning the electric motor and the rotating shaft of the wheel. As a result, a plurality of electric motors can be provided and can be driven by inputting the power of each electric motor to the planetary gear mechanism, so that the overall heat capacity of the plurality of electric motors can be increased.

Further, according to the present invention, the ring gear is provided with the one-way clutch that transmits power when the second electric motor is driven in the direction in which the vehicle travels. Therefore, it can be used when assisting the torque of the first motor with the second motor. Moreover, since it can drive | work without driving a 2nd motor excessively, the electrical or mechanical energy loss by driving a 2nd motor can be reduced.

Furthermore, according to the present invention, a plurality of teeth that mesh with the gear connected to the output shaft of the second electric motor are formed on the outer peripheral surface of the ring gear. Therefore, the gear for transmitting power from the second electric motor to the ring gear can be arranged at the same position in the axial direction as the planetary gear mechanism. Therefore, since the location which arrange | positions an electric motor in an axial direction can be ensured, a some electric motor can be provided and each electric motor can be enlarged in an axial direction. As a result, the volume of the entire electric motor can be increased and the heat capacity can be increased.

Furthermore, according to the present invention, in addition to the above configuration, an electronic control device for controlling the first electric motor and the second electric motor is provided. In addition, the electronic control unit includes a torque calculating unit that calculates an output torque of each electric motor based on a request torque output from the wheel, and a rotation speed of each electric motor based on the torque of each electric motor calculated by the torque calculating unit. And a rotation speed calculation means for calculating. Therefore, the torque and rotation speed of each electric motor can be calculated based on the required torque output from the wheel.

Furthermore, according to the present invention, the rotation speed calculation means further includes means for changing the rotation speed of each electric motor based on the state of each electric motor. Therefore, it is possible to change the rotation speed of the motor whose state of the motor is deteriorated so that the load is reduced.

Furthermore, according to the present invention, since the state of each motor includes the temperature state of each motor, the temperature of the motor can be changed by changing the number of revolutions of the motor when the temperature of any of the motors is high. The rise can be suppressed or prevented.

Furthermore, according to the present invention, the temperature state of each electric motor is determined by comparing a predetermined temperature based on the temperature that restricts the driving of each electric motor with the temperature of each electric motor, and the rotation speed calculating means includes the first electric motor. When the temperature of either one of the second motor and the second motor is higher than a predetermined temperature, the rotational speed of the motor having a temperature higher than the predetermined temperature is set to a rotational speed with a small power loss, and the rotational speed of the other motor is set to a temperature higher than the predetermined temperature. Further, a means for rotating the motor so as to compensate for a decrease in the rotational speed of the motor having a high value is further provided. Therefore, it is possible to suppress or prevent an increase in the temperature of the electric motor having a temperature higher than the predetermined temperature while maintaining the output rotational speed of the vehicle.

Furthermore, according to the present invention, each electric motor is further provided with a control device that controls the electric power supplied to each electric motor, and the rotation speed calculation means changes the rotation speed of each electric motor based on the temperature of the control device. Since it is further provided with means, the temperature rise of the control device is suppressed or prevented by changing the number of revolutions of the motor to which power is supplied from the control device when the temperature of any of the control devices is high. be able to.

Furthermore, according to the present invention, the electric power storage device is further provided for supplying electric power to each electric motor or charging electric power generated by each electric motor, and the rotation speed calculating means rotates the electric motor according to the charging state of the electric power storage device. Since the means for calculating the number is further provided, it is possible to suppress or prevent the power storage device from being overcharged.

Furthermore, according to the present invention, the electronic control device further includes a navigation system that presents a travel route on which the vehicle travels, and the electronic control device predicts a heat generation amount of each electric motor when traveling on the travel route presented by the navigation system. And means for calculating the number of revolutions of each motor based on the predicted amount of heat generated by each motor. Within the range, the rotation speed of each electric motor can be set to a rotation speed with low power loss.

It is a schematic diagram for demonstrating the structural example of the in-wheel motor which concerns on this invention. It is II-II sectional drawing in FIG. It is a collinear diagram which shows the relationship of the rotation speed of each motor and a carrier. It is a flowchart for demonstrating the example of control of the in-wheel motor of the structure of FIG. It is an efficiency map of the 1st motor. It is an efficiency map of the 2nd motor. It is a graph which shows the relationship between the output torque of a 1st motor and a 2nd motor, and efficiency. It is a flowchart for demonstrating the example of control which determines the rotation speed of each motor. It is a schematic diagram for demonstrating the other structural example of the in-wheel motor which concerns on this invention. It is a schematic diagram for demonstrating the further another structural example of the in-wheel motor which concerns on this invention. It is a collinear diagram which shows the relationship of the rotation speed of each motor and carrier in the in-wheel motor. It is an alignment chart for demonstrating that a 2nd motor functions as torque assist.

Next, the present invention will be specifically described. FIG. 1 and FIG. 2 are schematic views for explaining a configuration example of an in-wheel motor according to the present invention. The in-wheel motor 1 shown in the figure is provided on a steered wheel, and is provided with a ball joint 3 and a brake caliper 4 connected to an end of a tie rod arranged from the vehicle side toward the wheel 2 side. ing. Therefore, a plurality of

motors

5, 6, 7, and 8 and a planetary gear mechanism 9 are provided so as to avoid a place where these

members

3 and 4 are disposed. Specifically, the configuration will be described. First, a first motor / generator (hereinafter simply referred to as a first motor 5) is provided on the same axis as the rotation axis of the wheel 2. The first motor 5 is a conventionally known AC motor such as a synchronous motor or an induction motor, and has a function as an electric motor and a function as a generator. A planetary gear mechanism 9 is connected to the output shaft 10 of the first motor 5.

Here, the configuration of the planetary gear mechanism 9 will be briefly described. A sun gear 9S integrally connected to the input shaft of the planetary gear mechanism 9, that is, the output shaft 10 of the first motor 5, and the sun gear 9S meshing with the sun gear 9S and rotating. A plurality of pinion gears 9P that revolve around the input shaft, a carrier 9C that holds the pinion gears 9P and 9P rotatably, and outputs power from the planetary gear mechanism 9 when the pinion gear 9P revolves, and each pinion gear A planetary gear mechanism 9 is configured by the ring gear 9R having an internal gear meshing with the

gear

9P and 9P.

A plurality of motor generators (hereinafter simply referred to as a plurality of

motors

6, 7, etc.) having the same configuration as the first motor 5 on the outer peripheral side of the first motor 5 at the same position as the first motor 5 in the axial direction of the wheel 2. 8) is arranged. A gear 11 provided on each output shaft of the plurality of

motors

6, 7, and 8 is connected to a ring gear 9 R in the planetary gear mechanism 9. That is, a plurality of teeth that mesh with the gears 11 provided on the output shafts of the plurality of

motors

6, 7, and 8 are formed on the outer peripheral side of the ring gear 9 R.

Therefore, the in-wheel motor 1 having the above-described configuration can place the planetary gear mechanism 9 and the gear 11 in the same position in the axial direction of the wheel 2, and as a result, the first motor 5 and the plurality of

motors

6, 7, 8. And the size of each

motor

5, 6, 7, 8 in the axial direction can be increased. As a result, the overall volume of the

motors

5, 6, 7, and 8 for obtaining the driving force of the vehicle can be increased, so that the overall heat capacity of the

motors

5, 6, 7, and 8 can be increased. it can.

The

motors

5, 6, 7, and 8 described above are driven in accordance with the energized power, and the

motors

5, 6, 7, and 8 have

inverters

12, 13, 14, 15 respectively. Are connected, and the power storage device 16 is connected to the

inverters

12, 13, 14, and 15. Further, an electronic control unit 17 is connected to the

inverters

12, 13, 14, 15. The electronic control unit 17 stores various maps and arithmetic expressions determined in advance through experiments and the like, and supplies them to the

inverters

12, 13, 14, and 15 based on signals input to the electronic control unit 17. It is comprised so that the electric power to perform may be controlled. Here, as an example of a sensor connected to the electronic control unit 17 and inputting a signal, an accelerator opening sensor that detects the amount of depression of the accelerator that changes according to the driver's operation, and each of the

motors

5, 6, 7, 8

Temperature sensors

18, 19, 20, 21 for detecting the temperature of the motor,

speed sensors

22, 23, 24, 25 for detecting the rotational speed of the

motors

12, 13, 14, 15, and vehicle speed for detecting the rotational speed of the carrier 9C. Sensor 26,

temperature sensors

27, 28, 29, and 30 that detect the temperature of each inverter, sensor 31 that detects the temperature of power storage device 16, sensor 32 that detects the amount of charge (SOC: State 充電 of Charge１６) of power storage device 16, and the like There is. Therefore, the torque or rotational speed output from each of the

motors

5, 6, 7, and 8 is determined from the signals input from the sensors, and the

inverters

12, 13, 14, and 15 are controlled so as to obtain the torque and rotational speed. can do.

The in-wheel motor 1 configured as described above outputs vehicle output torque from the planetary gear mechanism 9 connected to the first motor 5 and the plurality of

motors

6, 7, 8. That is, the rotation speed output according to the rotation speed of the first motor 5 and the plurality of

motors

6, 7, 8 can be determined. In the following description, for the sake of convenience, a configuration in which only the second motor 6 is provided on the outer peripheral side of the first motor 5 will be described as an example. FIG. 3 is a collinear diagram showing the rotational speed relationship between the carrier 9C and the second motor 6 in the first motor 5 and the planetary gear mechanism 9, and the first motor 5 and the carrier 9C from the left side of the vertical axis in the figure. The rotational speed of the second motor 6 is shown. The horizontal axis in the figure indicates that the rotational speed is 0 (zero), the upper side from the horizontal axis indicates the rotational direction when the vehicle travels forward, and the lower side indicates the rotational direction when travels backward. It shows that the number of rotations increases as the distance from the horizontal axis increases. The intervals between the vertical axes indicate the speed ratio a between the first motor 5 and the carrier 9C and the speed ratio b between the carrier 9C and the second motor 6.

3, the rotational speed of the carrier 9 C is determined by the relationship between the rotational speeds of the first motor 5 and the second motor 6. Therefore, the rotation speed of the first motor 5 and the rotation speed of the second motor 6 are in the state I shown in the figure, that is, the first motor 5 is at a low rotation speed and the second motor 6 is at a high rotation speed. Even in the state II shown in the drawing, that is, when the first motor 5 has a high rotation speed and the second motor 6 has a low rotation speed, the rotation speed of the carrier 9C can be made the same. That is, the rotation speeds of the first motor 5 and the second motor 6 can be changed while the rotation speed of the carrier 9C is constant.

Next, control of the in-wheel motor 1 having the above-described configuration will be described with reference to a flowchart shown in FIG. First, based on the accelerator opening detected by the accelerator opening sensor, an output torque required for the vehicle (hereinafter simply referred to as a required torque) is calculated, and each of the

motors

5 and 6 is calculated according to the required torque. An output torque is calculated (step S1). Specifically, as shown in Equation 1, the required torque is the sum of the output torque of the first motor 5 and the output torque of the second motor 6, and as shown in Equation 2, each

motor

5 , 6 and the output torque of each of the

motors

5, 6 and the carrier 9C are the same value, so that the output torques of the

motors

5, 6 can be calculated from the equations 1 and 2. it can. That is, the torque of the first motor 5 is calculated by Expression 3, and the torque of the second motor 6 is calculated by Expression 4.
Tall = TmgA + TmgB (1)
TmgA * a = TmgB * b (2)
TmgA = Tall * b / (a + b) (3)
TmgB = Tall * a / (a + b) (4)

Next, a graph indicating the relationship between the rotational speed of each

motor

5 and 6 and the efficiency is calculated from the output torque of each

motor

5 and 6 calculated in step S1 and the vehicle speed detected by the vehicle speed sensor 26 (step S2). ). Specifically, a graph indicating the relationship between the motor rotation speed and the efficiency is calculated from the motor efficiency map prepared in advance by experiments or simulations and the motor output torque calculated in step S1. FIGS. 5 and 6 show examples of the efficiency maps of the

motors

5 and 6. In the torque indicated by the thick line in the figure, the right side of the figure is highly efficient, and the efficiency decreases as it becomes the left side. It is shown that. FIG. 7 is a graph showing the relationship between the output torque and the efficiency when the torque indicated by the bold line is output. The rotational speed relationship between the first motor 5 and the second motor 6 can be calculated from the rotational speed Nc of the carrier 9C from the vehicle speed and the rotational speed Nc of the carrier 9C and each gear ratio. Expression 5 is an expression for calculating the relationship between the rotational speeds of the first motor 5 and the second motor 6.
NmgB = (a + b) / a * (Nc−NmgA) + NmgA (5)

Each motor 5 is obtained by matching the horizontal axes of the first motor 5 and the second motor 6 shown in FIG. 7 so that the rotational speed relationship between the first motor 5 and the second motor 6 obtained from Equation 5 is satisfied. , 6 can be calculated in the figure.

Then, the rotational speeds of the

motors

5 and 6 are determined from the graph showing the relationship between the output torque calculated in step S2 and the efficiency (step S3). Usually, in determining the number of rotations of the motor, the number of rotations where the loss of each of the first motor 5 and the second motor 6 is small, that is, an efficient number of rotations is determined. It is preferable to determine the number of rotations. Therefore, here, a control example in which the temperatures of the

motors

5 and 6 are detected and the rotation speeds of the

motors

5 and 6 are determined according to the temperature state will be described. FIG. 8 is a flowchart for explaining the control example. First, it is calculated whether or not the temperature of the first motor 5 is equal to or lower than a predetermined temperature (step S31). Here, the predetermined temperature is a temperature obtained by adding a margin, for example, 0.9 to the limit temperature of the first motor 5. In other words, since the motor generates heat due to copper loss or the like by outputting torque, a predetermined temperature is set so that the temperature of the first motor 5 does not become the limit temperature when driven by outputting the calculated torque. Yes.

If the temperature of the first motor 5 is lower than the predetermined temperature and an affirmative determination is made in step S31, it is determined whether or not the temperature of the second motor 6 is equal to or lower than the predetermined temperature (step S32). The predetermined temperature here is a temperature obtained by adding a margin, for example, 0.9 to the limit temperature of the second motor 6 in the same manner as the predetermined temperature in step S31. If the determination in step S32 is affirmative, that is, if the temperature of each of the

motors

5 and 6 is not more than a predetermined temperature, the total loss of the first motor 5 and the second motor 6 is minimized. The

motors

5 and 6 are driven at the rotational speed (step S33). That is, as shown in FIG. 8, the

motors

5 and 6 are rotated at the number of rotations (hereinafter simply referred to as the operating point X) where the curves indicating the losses of the

motors

5 and 6 intersect.

On the other hand, if a negative determination is made in step S32, the temperature of the second motor 6 is high, so that the efficiency of the second motor 6 is prioritized, that is, the speed at which the efficiency of the second motor 6 is good. Then, the

motors

5 and 6 are driven (step S34). Specifically, the efficiency of the second motor 6 is good and the loss of the first motor 5 increases, that is, in the Y region on the left side of the operating point X shown in FIG. 7 and according to the temperature of the second motor 6. The

motors

5 and 6 are driven at the determined rotational speed.

On the other hand, when a negative determination is made in step S31, that is, when the temperature of the first motor 5 is higher than the predetermined temperature, it is determined whether or not the temperature of the second motor 6 is equal to or lower than the predetermined temperature (step S35). The determination in step S35 is the same as that in step S32. If the determination in step S35 is affirmative, that is, if the temperature of the second motor 6 is equal to or lower than the predetermined temperature, the temperature of the first motor 5 is high, so that the efficiency of the first motor 5 is given priority. The

motors

5 and 6 are driven at a rotational speed at which the efficiency of the first motor 5 is good (step S36). Specifically, the efficiency of the first motor 5 is good and the loss of the second motor 6 increases, that is, in the Z region on the right side of the operating point X shown in FIG. 7 and according to the temperature of the first motor 5. The

motors

5 and 6 are driven at the determined rotational speed.

On the other hand, if a negative determination is made in step S35, the required torque cannot be output because the

motors

5 and 6 are at a predetermined temperature or higher. Therefore, the output torque of the

motors

5 and 6 is reduced, that is, the output torque of the vehicle is limited, and torque within a range that can be output by the

motors

5 and 6 is output. In this case, since the

motors

5 and 6 are at a high temperature, the

motors

5 and 6 are driven at a rotational speed at which the total loss of the first motor 5 and the second motor 6 is minimized. That is, each of the rotational speeds corresponding to the operating point X on the graph showing the relationship between the output torque of the first motor and the second motor calculated based on the torque that can be output by the

motors

5 and 6 and the efficiency. The

motors

5 and 6 are driven.

In short, the above-described control example is that, when each of the

motors

5 and 6 is at a predetermined temperature or less, the

motors

5 and 5 are rotated at a rotational speed that minimizes the total loss of the first motor 5 and the second motor 6. 6 is driven, and when the temperature of any of the motors 5 (6) is higher than a predetermined temperature, the temperature rise is suppressed by driving the motor 5 (6) on the higher temperature side at a high speed. However, the motor 6 (5), which has a low temperature and has a margin to the limit temperature, is configured to be driven to compensate for the shortage. Therefore, since the in-wheel motor 1 having the above-described configuration can change the rotation speeds of the

motors

5 and 6, both the

motors

5 and 6 can be set to a high-efficiency rotation speed, and the temperature is The temperature rise can be suppressed or prevented by setting the higher rotational speed to an efficient rotational speed.

Further, a configuration in which the navigation system 33 is provided in the in-wheel motor 1 having the above-described configuration will be described. FIG. 9 is a diagram for explaining the configuration, and a navigation system 33 is connected to the electronic control device 16. That is, signals such as the planned travel route, the road surface condition or traffic jam information presented by the navigation system 33 are input to the electronic control device 16. Then, the electronic control unit 16 can determine the rotation speed of each of the

motors

5 and 6 based on information such as a planned travel route and a road surface condition, that is, whether the route to be traveled in the future is an uphill road or a downhill road. .

Therefore, when it is determined from the information input from the navigation system 33 that the planned travel route is not an uphill road, the load applied to the

motors

5 and 6 or the torque output from the

motors

5 and 6 is low and there is no excessive temperature rise. Can reduce the margin shown in the above control example and rotate the

motors

5 and 6 at an efficient rotational speed. That is, even if the temperature of one motor 5 (6) is high and negative determination is made in step S31 or step S32 in the above control example, the margin is reduced to a predetermined temperature or less by reducing the margin. In some cases, the motor can be driven at the operating point X, or even when one of the motors 5 (6) is driven in a region with a large loss, the motor can be driven at a rotational speed with a smaller loss. Therefore, since the

motors

5 and 6 can be rotated without excessively increasing the losses of the

motors

5 and 6, power loss for driving the

motors

5 and 6 can be reduced.

In addition, when the in-wheel motor 1 having the above-described configuration performs regenerative braking, it is usually preferable that the

motors

5 and 6 regenerate at a low rotational speed, but the electric power charged in the

power storage devices

12 and 13 If the amount is high, it will be overcharged. Therefore, in-wheel motor 1 according to the present invention, when the amount of electric power charged in

power storage devices

12 and 13 is low, the charged electric power with the rotational speed of each

motor

5 and 6 being the rotational speed with a low total loss. When the amount is high, the

motors

5 and 6 are configured so that the total loss is regenerated at a large rotational speed. With such a configuration, the regenerative energy is changed to thermal energy by the

motors

5 and 6, so that overcharging can be suppressed or prevented.

Further, a configuration example in which the one-way clutch 34 is provided in the in-wheel motor 1 in the above-described configuration example will be described. FIG. 10 is another configuration example in which the one-way clutch 34 is provided in the in-wheel motor 1 in the configuration example described above. As shown in the figure, the one-way clutch 34 is provided on the ring gear 9 R in the planetary gear mechanism 9. The one-way clutch 34 is configured to allow the second motor 6 to rotate in the direction in which the wheel 2 is driven, and to suppress rotation in the opposite direction, that is, rotation in the direction in which the second motor 6 is regenerated. It has been done. Therefore, when the second motor 6 is not driven as shown in the alignment chart shown in FIG. 11, the rotation speed of the carrier 9 R, that is, the rotation speed of the wheel 2 is determined according to the rotation speed of the first motor 5.

On the other hand, when the rotation speed of the first motor 5 is high or when the temperature of the first motor 5 is high and the rotation speed is limited, as shown in FIG. By rotating the first motor 5 at a constant speed, the rotational speed of the first motor 5 can be reduced while keeping the rotational speed of the carrier 9C constant. That is, the second motor 6 can function as torque assist for the first motor 5. Further, if a third motor is provided in addition to the second motor 6 on the outer peripheral side of the ring gear 9R, the third motor is driven to assist the torque when the temperature of the second motor 6 rises. As a result, temperature rises of the first motor 5 and the second motor 6 can be suppressed.

The present invention is not limited to the above-described configuration. For example, a first pinion gear that meshes with the sun gear and a second pinion gear that revolves around the sun gear while rotating in rotation with the first pinion gear and meshes with the ring gear. A so-called double pinion gear provided may be used. In that case, what is necessary is just to make the rotation direction of the 2nd motor for driving a wheel the contrary to the structural example mentioned above. Furthermore, although the control example which considered the temperature of the motor was shown in the control example mentioned above, you may detect and control the temperature of an inverter, for example.

Further, in the configuration example in which the one-way clutch 34 is provided, the first motor 5 is mainly driven. However, for example, the one-way clutch 34 is provided in the sun gear 9S, and the first motor 5 is connected to the second motor 6. You may comprise so that a torque may be assisted.

Claims

In an in-wheel motor vehicle having a plurality of drive motors inside the wheel,
The plurality of drive motors include at least a first motor provided coaxially with a rotation shaft of the wheel, and a second motor disposed at the same position as the first motor in the axial direction of the wheel. And
An in-wheel motor vehicle characterized in that a planetary gear mechanism having a sun gear connected to an output shaft of the first motor and a ring gear to which power of the second motor is transmitted is provided inside the wheel. .
The in-wheel motor vehicle according to claim 1, wherein a one-way clutch that transmits power when the second electric motor is driven in a direction in which the vehicle travels forward on the ring gear is provided.
The in-wheel motor vehicle according to claim 1 or 2, wherein a plurality of teeth that mesh with a gear connected to an output shaft of the second electric motor are formed on an outer peripheral surface of the ring gear.
An electronic control unit for controlling electric power supplied to each of the first electric motor and the second electric motor;
The electronic control device includes: torque calculating means for calculating output torques of the first electric motor and the second electric motor based on a required torque output from the wheel;
4. The engine according to claim 1, further comprising a rotation speed calculation unit that calculates a rotation speed of each electric motor based on the torque of each electric motor calculated by the torque calculation unit. Wheel motor car.
The in-wheel motor vehicle according to claim 4, wherein the rotation speed calculation means further includes means for changing the rotation speed of each electric motor based on the state of each electric motor.
6. The in-wheel motor vehicle according to claim 5, wherein the state of each electric motor includes a temperature state of each electric motor.
The temperature state of each electric motor is determined by comparing a predetermined temperature based on a temperature that restricts driving of each electric motor with the temperature of each electric motor,
When the temperature of either one of the first motor and the second motor is higher than the predetermined temperature, the rotation speed calculation means calculates the rotation speed of the motor whose temperature is higher than the predetermined temperature as a rotation with a small power loss. The in-wheel motor vehicle according to claim 6, further comprising means for rotating the rotational speed of the other electric motor so as to compensate for a decrease in the rotational speed of the electric motor whose temperature is higher than the predetermined temperature. .
Each of the electric motors further comprises a control device that controls electric power supplied to the electric motors,
The in-wheel motor vehicle according to any one of claims 4 to 7, wherein the rotation speed calculation means further includes means for changing the rotation speed of each electric motor based on the temperature of the control device. .
A power storage device for supplying electric power to each electric motor or charging electric power generated by each electric motor;
The in-wheel motor according to any one of claims 4 to 8, wherein the rotation speed calculation means further includes means for calculating the rotation speed of each electric motor in accordance with a state of charge of the power storage device. car.
A navigation device for presenting a travel route on which the vehicle travels;
The electronic control unit predicts the amount of heat generated by each electric motor when traveling along the travel route presented by the navigation device;
The in-wheel motor vehicle according to any one of claims 4 to 9, further comprising means for calculating the number of revolutions of each electric motor based on a predicted heat generation amount of each electric motor.