JP7380356B2 - Vehicle control device, program - Google Patents

Description

The present disclosure relates to a vehicle control device and a program .

Conventionally, there is a vehicle control device described in Patent Document 1 below. This vehicle is a so-called electric vehicle that travels by transmitting power from an electric motor to drive wheels. The control device sets a torque command value, which is a target value of the output torque of the electric motor, based on various state quantities of the vehicle. The control device calculates a filtered torque command value by subjecting the torque command value to a filtering process for suppressing vibration of a drive shaft connected to a drive wheel. Further, the control device calculates an estimated value of the angular velocity of the electric motor in the process of calculating the filtered torque command value. The control device calculates a torque correction value based on the difference between the calculated estimated value of the angular velocity of the electric motor and the actual angular velocity of the electric motor, and adds the calculated torque correction value to the filtered torque command value. By doing so, the final torque command value is determined. The control device performs feedback control of the output torque of the electric motor based on the determined final torque command value.

JP2017-225278A

In a vehicle as described in Patent Document 1, when the electric motor is outputting positive torque, that is, when the vehicle is traveling forward, the road surface on which the vehicle is traveling changes from a road surface state with a low road surface friction coefficient. When the road condition changes to a road surface with a high coefficient of friction, negative torque is applied to the drive wheels. Similarly, negative torque is applied to the wheels when the drive wheels go over a step while the vehicle is traveling forward, or when braking torque is applied to the wheels by a friction brake device or the like. When such negative torque is applied to the drive wheels, the drive shaft connected to the drive wheels may be twisted. Twisting in the drive shaft results in a change in the angular velocity of the electric motor. When a change occurs in the angular velocity of the electric motor, the control device described in Patent Document 1 performs feedback control of the output torque of the electric motor by correcting the torque command value based on the change in the angular velocity of the electric motor. It has become so.

On the other hand, in a situation where negative torque is applied to the drive wheels as described above, the angular velocity of the electric motor does not change until the drive shaft is completely twisted. Therefore, in the case of a configuration in which the output torque of the electric motor is feedback-controlled based on the angular velocity of the electric motor, such as the control device described in Patent Document 1, from the time when the drive shaft starts to twist until the drive shaft is completely twisted. The timing at which correction of the torque command value is started is delayed by the period of . Therefore, with the control device described in Patent Document 1, it is difficult to avoid twisting of the drive shaft. Once the drive shaft is twisted, vibrations occur as the twist is released. When the vibrations of the drive shaft are transmitted to the vehicle body, there is a risk that the entire vehicle may vibrate.

The present disclosure has been made in view of these circumstances, and an object thereof is to provide a vehicle control device and program that can suppress vehicle vibrations caused by drive shaft torsion.

A vehicle control device that solves the above problems is a control device that controls electric motors (20, 70) that transmit torque to drive wheels (11, 12, 13, 14) of a vehicle (10), A torque sensor (51, 52, 53 , 54) that detects the torque applied to the drive shaft (24, 74) that transmits the torque of 631). The motor control unit determines whether or not the drive shaft is twisted, and if it is determined that the drive shaft is not twisted, the motor control unit converts the basic torque command value sent from the host controller to the final torque command value. If it is determined that the drive shaft is twisted, the basic torque command value is corrected based on the torque detected by the torque sensor, and the corrected torque command value is set as the final torque command value. do.
A program for solving the above problem is a program that controls an electric motor (20, 70) that transmits torque to drive wheels (11, 12, 13, 14) of a vehicle (10), and includes at least one processing unit ( 63) detects the torque applied to the drive shaft (24, 74) that transmits the torque of the electric motor to the drive wheels, controls the electric motor based on the final torque command value, and determines whether or not the drive shaft is twisted. If it is determined that the drive shaft is not twisted, the basic torque command value sent from the host controller is set to the final torque command value, and it is determined that the drive shaft is twisted. In this case, the basic torque command value is corrected based on the torque applied to the drive shaft, and the corrected torque command value is set as the final torque command value.

According to this configuration, when a torque that causes twisting is applied to the drive shaft due to a disturbance applied to the drive wheels, a change in the torque is detected by the torque sensor. Thereby, the twist of the drive shaft can be detected by a change in torque before the drive shaft is completely twisted. Therefore, by controlling the electric motor based on the torque detected by the torque sensor and the output torque of the electric motor, the electric motor can be controlled so that the twist is removed from the drive shaft before the drive shaft is completely twisted. can be controlled. Therefore, it is possible to prevent the drive shaft from completely twisting, so it is possible to suppress vibrations of the vehicle caused by the twist of the drive shaft.

Note that the above-mentioned means and the reference numerals in parentheses described in the claims are examples showing correspondences with specific means described in the embodiments to be described later.

According to the vehicle control device and program of the present disclosure, it is possible to suppress vibrations of the vehicle caused by torsion of the drive shaft.

FIG. 1 is a block diagram showing a schematic configuration of a vehicle according to a first embodiment. FIG. 2 is a block diagram showing the electrical configuration of the vehicle according to the first embodiment. FIG. 3 is a flowchart showing the procedure of processing executed by the motor control unit of the first embodiment. FIG. 4 is a timing chart showing changes in the drive shaft torque detection value Td, the motor generator output torque Tm, and the final torque command value T* in the vehicle of the first embodiment. FIG. 5 is a block diagram showing a schematic configuration of a vehicle according to a first modification of the first embodiment. FIG. 6 is a flowchart showing the procedure of processing executed by the motor control unit of the second modification of the first embodiment. FIG. 7 is a block diagram showing the procedure for calculating the final torque command value by the motor control section of the second embodiment. FIG. 8 is a block diagram showing a schematic configuration of a vehicle according to another embodiment.

Hereinafter, one embodiment of a vehicle control device will be described with reference to the drawings. In order to facilitate understanding of the description, the same components in each drawing are denoted by the same reference numerals as much as possible, and redundant description will be omitted.
First, a schematic configuration of a vehicle in which the control device of this embodiment is mounted will be described.

As shown in FIG. 1, the vehicle 10 of this embodiment includes a motor generator 20, an inverter device 21, a battery 22, and a differential device 23. Vehicle 10 is a so-called electric vehicle that uses motor generator 20 as a driving power source.
Inverter device 21 converts DC power stored in battery 22 into three-phase AC power, and supplies the converted three-phase AC power to motor generator 20 .

Motor generator 20 operates as an electric motor and a generator. When operating as an electric motor, motor generator 20 is driven based on three-phase AC power supplied from inverter device 21 . The driving force of the motor generator 20 is transmitted to the right front wheel 11 and the left front wheel 12 of the vehicle 10 via the differential device 23 and the drive shaft 24, so that the right front wheel 11 and the left front wheel 12 rotate, and the vehicle 10 runs. do. In the vehicle 10, the right front wheel 11 and the left front wheel 12 function as driving wheels, and the right rear wheel 13 and the left rear wheel 14 function as driven wheels. Hereinafter, the right front wheel 11 will be referred to as the "right drive wheel 11," the left front wheel 12 will be referred to as the "left drive wheel 12," and the right front wheel 11 and the left front wheel 12 will be collectively referred to as "drive wheels 11, 12." In this embodiment, motor generator 20 corresponds to an electric motor.

Motor generator 20 operates as a generator when braking the vehicle. Specifically, when the vehicle 10 is braked, the braking force applied to the drive wheels 11 and 12 is input to the motor generator 20 via the drive shaft 24 and the differential gear 23. The motor generator 20 generates electricity based on the power reversely inputted from the drive wheels 11 and 12. Three-phase AC power generated by motor generator 20 is converted into DC power by inverter device 21 and charged into battery 22 .

The differential device 23 is configured by a combination of a plurality of rotating elements, and when a difference occurs between the rotational speeds of the right drive wheel 11 and the left drive wheel 12, it absorbs the difference in rotational speed. At the same time, the driving force transmitted from the motor generator 20 is distributed and transmitted to the right drive wheel 11 and the left drive wheel 12.

The wheels 11 to 14 of the vehicle 10 are provided with friction brake devices 31 to 34, respectively. The friction brake devices 31 to 34 are devices that apply braking force to each wheel 11 to 14 by applying friction force to a rotating body that rotates together with each wheel 11 to 14.
Next, the electrical configuration of the vehicle 10 will be explained.

As shown in FIG. 2, the vehicle 10 includes wheel speed sensors 41 to 44, an acceleration sensor 45, a yaw rate sensor 46, a brake switch 47, an accelerator opening sensor 48, and torque sensors 51 and 52. ing. The vehicle 10 also includes an ESC-ECU (Electronic Stability Control-Electronic Control Unit) 61, an EV-ECU (Electric Vehicle-Electronic Control Unit) 62, and an MG-ECU (Motor Generator-Electronic Control Unit) as parts that perform various controls. control unit) 63. Each of the ECUs 61 to 63 is mainly composed of a microcomputer having a CPU, memory, and the like. In this embodiment, a control device 60 is configured by ECUs 61 to 63.

As shown in FIG. 1, wheel speed sensors 41-44 are provided on wheels 11-14, respectively. The wheel speed sensors 41 to 44 detect wheel speeds ωw11 to ωw14, which are the rotational speeds of the wheels 11 to 14, respectively, and send signals corresponding to the detected wheel speeds ωw11 to ωw14 to the ESC-ECU 61 shown in FIG. Output to.

The acceleration sensor 45 detects the lateral acceleration of the vehicle 10 and outputs a signal corresponding to the detected lateral acceleration to the ESC-ECU 61.
The yaw rate sensor 46 detects the yaw rate, which is the angular velocity of the vehicle 10 around the vertical axis, and outputs a signal corresponding to the detected yaw rate to the ESC-ECU 61.

The brake switch 47 detects whether or not the brake pedal of the vehicle 10 is depressed, and outputs a signal to the ESC-ECU 61 in accordance with the detection result.
The accelerator opening sensor 48 detects the accelerator opening, which is the amount of depression of the accelerator pedal of the vehicle 10, and outputs a signal corresponding to the detected accelerator opening to the EV-ECU 62.

As shown in FIG. 1, torque sensors 51 and 52 are provided at both ends of the drive shaft 24, respectively. One torque sensor 51 is provided near one end 241 of the drive shaft 24 connected to the right drive wheel 11, and detects the torque applied to the one end 241 of the drive shaft 24. The other torque sensor 52 is provided near the other end 242 of the drive shaft 24 connected to the left drive wheel 12, and detects the torque applied to the other end 242 of the drive shaft 24. The torque sensors 51 and 52 are assumed to detect torque using sensors such as magnetostrictive type, strain gauge type, and capacitance type. As shown in FIG. 2, the torque sensors 51 and 52 output signals corresponding to the detected torque to the MG-ECU 63 of the inverter device 21.

The ESC-ECU 61 executes vehicle behavior control to stabilize the attitude of the vehicle 10 by executing a program stored in advance in its memory. The vehicle behavior control is, for example, skid prevention control that suppresses skidding of the vehicle 10. Specifically, the ESC-ECU 61 determines whether oversteer or understeer is occurring in the vehicle 10 based on the lateral acceleration of the vehicle 10 detected by the acceleration sensor 45 and the yaw rate of the vehicle 10 detected by the yaw rate sensor 46. Determine whether or not. When oversteer or understeer is detected, the ESC-ECU 61 automatically adjusts the posture of the vehicle 10 to bring it closer to the ideal driving condition by applying braking force to each wheel 11 to 14 using the friction brake devices 31 to 34. Control.

The ESC-ECU 61 also provides a brake that applies braking force to each of the wheels 11 to 14 using the friction brake devices 31 to 34 when it is detected that the brake pedal of the vehicle 10 is depressed based on the output signal of the brake switch 47. It also performs control, etc.
The MG-ECU 63 is provided in the inverter device 21. MG-ECU 63 controls the operation of motor generator 20 by executing a program stored in advance in its memory. The MG-ECU 63 includes a torque calculation section 630 and a motor control section 631.

The torque calculation unit 630 calculates the torque of one end 241 of the drive shaft 24 based on the output signal of the torque sensor 51, and calculates the torque of the other end 242 of the drive shaft 24 based on the output signal of the torque sensor 52. do.
Motor control unit 631 controls motor generator 20 by driving inverter device 21 based on a request from EV-ECU 62. For example, when the MG-ECU 63 receives a torque command value Tb*, which is a command value of the output torque of the motor generator 20, from the EV-ECU 62, the MG-ECU 63 performs the following commands: The energization control value of the motor generator 20 is calculated, and the inverter device 21 is driven based on the calculated energization control value. Furthermore, when braking the vehicle 10, the MG-ECU 63 drives the inverter device 21 so that the battery 22 is charged with the electric power generated by regenerative power generation of the motor generator 20.

Note that the motor generator 20 is provided with a rotation sensor 200. Rotation sensor 200 detects a rotation angle θm of the output shaft of motor generator 20 and outputs a signal corresponding to the detected rotation angle θm to MG-ECU 63. The inverter device 21 is provided with a current sensor 210. Current sensor 210 detects each phase current value Im flowing through each phase of motor generator 20 and outputs a signal corresponding to each detected phase current value Im to MG-ECU 63. The MG-ECU 63 is capable of acquiring information on the rotation angle θm of the motor generator 20 based on the output signal of the rotation sensor 200, and also obtains each phase current value of the motor generator 20 based on the output signal of the current sensor 210. It is possible to obtain information about Im.

The EV-ECU 62 comprehensively controls the running of the vehicle 10 by executing a program stored in advance in its memory. Specifically, the EV-ECU 62 receives driver operation information such as the accelerator opening detected by the accelerator opening sensor 48, state quantities of the vehicle 10 detected by various sensors mounted on the vehicle 10, and the ESC. - Setting the torque command value Tb* based on the information that can be obtained from the ECU 61 and the MG-ECU 63. The EV-ECU 62 transmits the set torque command value Tb* to the MG-ECU 63. Based on this torque command value Tb*, the MG-ECU 63 executes the energization control of the motor generator 20 as described above, so that torque corresponding to the torque command value Tb* is output from the output shaft of the motor generator 20. Through such torque control of the motor generator 20, running of the vehicle 10 is realized in accordance with the driver's driving request and the running state of the vehicle 10. Hereinafter, for convenience, the torque command value Tb* transmitted from the EV-ECU 62 to the MG-ECU 63 will be referred to as a "basic torque command value Tb*."

By the way, in such a vehicle 10, when the motor generator 20 is outputting positive torque, that is, when the drive wheels 11 and 12 cross a step while the vehicle 10 is traveling forward, the drive wheels 11 and 12 are subjected to negative torque in the opposite direction to their rotational direction. This negative torque becomes a disturbance applied to the drive wheels 11 and 12. If the drive shaft 24 is twisted due to the negative torque applied to the drive wheels 11 and 12, vibrations may occur in the power transmission system from the motor generator 20 to the drive wheels 11 and 12. Since such vibrations cause the entire vehicle 10 to vibrate, there is a risk that the occupants of the vehicle 10 may feel uncomfortable.

Therefore, when the motor control unit 631 of the MG-ECU 63 of this embodiment detects the torsion of the drive shaft 24, it executes a process of adjusting the output torque of the motor generator 20 in a direction in which the torsion is alleviated. Next, with reference to FIG. 3, a specific procedure of processing executed by this motor control section 631 will be described. Note that the motor control unit 631 repeatedly executes the process shown in FIG. 3 at a predetermined cycle.

As shown in FIG. 3, the motor control unit 631 first acquires the basic torque command value Tb* transmitted from the EV-ECU 62 as the process of step S10, and then acquires the basic torque command value Tb* as the process of the subsequent step S11. Execute torque control of motor generator 20 using Tb*. Specifically, motor control unit 631 controls motor generator 20 based on rotation angle θm of motor generator 20 detected by rotation sensor 200 and each phase current value Im of motor generator 20 detected by current sensor 210. The estimated value Tm of the output torque is calculated using an arithmetic expression or the like. Further, the motor control unit 631 uses the basic torque command value Tb* acquired in the process of step S10 as it is as the final torque command value T*. The motor control unit 631 calculates the energization control value of the motor generator 20 by executing feedback control to make the estimated output torque Tm of the motor generator 20 follow the final torque command value T*, and also adjusts the energization control value to the calculated energization control value. The inverter device 21 is controlled based on this. Through such feedback control, motor generator 20 outputs torque according to basic torque command value Tb*. Hereinafter, the torque control executed in step S11 will be referred to as "basic torque control."

Note that the basic torque control executed in step S11 is not limited to feedback control, but may be feedforward control based on the final torque command value T*.
As a process in step S12 following step S11, the motor control unit 631 determines whether or not the drive shaft 24 is twisted based on the torque detected by the torque sensors 51 and 52 and the estimated output torque Tm of the motor generator 20. Determine whether Specifically, this determination process is performed as follows.

In vehicle 10 , the output torque of motor generator 20 is distributed to drive wheels 11 and 12 , so ideally the sum of the respective torques of drive wheels 11 and 12 is the output torque of motor generator 20 . However, since various devices such as the differential gear 23 are present in the torque transmission path from the motor generator 20 to the drive wheels 11 and 12, loss occurs in the torque transmission path. Therefore, the sum of the respective torques of drive wheels 11 and 12 is actually a smaller value than the output torque of motor generator 20. Since the torque sensors 51 and 52 are arranged at both ends 241 and 242 of the drive shaft 24, respectively, the torques detected by the torque sensors 51 and 52, respectively, are approximately the same as the torques of the drive wheels 11 and 12, respectively. Therefore, if the actual output torque of the motor generator 20 is "Tm", and the sum of the torques Tda and Tdb of the drive shaft 24 detected by the torque sensors 51 and 52, respectively, is "Td", as shown in FIG. , the detected torque value Td (=Tda+Tdb) of the drive shaft 24 is smaller than the output torque Tm of the motor generator 20.

If the drive wheels 11 and 12 run onto a step at time t10 shown in FIG. To increase. As a result, the detected torque value Td of the drive shaft 24 reaches the output torque Tm of the motor generator 20 at time t11, and thereafter the detected torque value Td of the drive shaft 24 shows a value larger than the output torque Tm of the motor generator 20. .

Therefore, the motor control unit 631 of this embodiment detects the respective torques Tda and Tdb at both ends 241 and 242 of the drive shaft 24 based on the respective output signals of the torque sensors 51 and 52, and calculates the sum of the torques Tda and Tdb. The detected torque value Td of the drive shaft 24 is determined by calculation. Then, the motor control unit 631 sets the output torque Tm of the motor generator 20 as the torsion determination value Ttha, and if the detected torque value Td of the drive shaft 24 is less than the torsion determination value Ttha, the motor control unit 631 sets the output torque Tm of the motor generator 20 as the torsion determination value Ttha. It is determined that there is no twist, and a negative determination is made in the process of step S12 shown in FIG. In this case, the motor control unit 631 temporarily ends the process shown in FIG. 3. Therefore, if the drive shaft 24 is not twisted, the motor control unit 631 continues to perform the process shown in step S11, that is, the basic torque control using the basic torque command value Tb*.

On the other hand, if the detected torque value Td of the drive shaft 24 is greater than or equal to the torsion determination value Ttha, the motor control unit 631 determines that the drive shaft 24 is torsion, and makes an affirmative determination in the process of step S12. conduct. In this case, the motor control unit 631 determines the corrected final torque command value T* based on the detected torque value Td of the drive shaft 24 as a process in the subsequent step S13.

Specifically, the motor control unit 631 calculates the deviation ΔT (=|Td−Tm|) between the detected torque value Td of the drive shaft 24 and the output torque Tm of the motor generator 20. Then, the motor control unit 631 calculates the corrected final torque command value T* by correcting the basic torque command value Tb* based on the following formula f1 using the deviation ΔT.

T*=Tb*-ΔT (f1)
The motor control unit 631 executes feedback control using the corrected final torque command value T* obtained in the process of step S13, as a process of step S14 following step S13. Specifically, the motor control unit 631 calculates the energization control value of the motor generator 20 by executing feedback control to make the estimated output torque Tm of the motor generator 20 follow the corrected final torque command value T*. , controls the inverter device 21 based on the calculated energization control value. Through such feedback control, the motor generator 20 outputs torque according to the torque command value (Tb*-ΔT). Hereinafter, the torque control executed in step S14 will be referred to as "twist elimination torque control."

The motor control unit 631 determines whether or not the twist in the drive shaft 24 has been resolved as a process in step S15 following step S14. Specifically, if the detected torque value Td of the drive shaft 24 is greater than or equal to the torsion elimination determination value Tthb, the motor control unit 631 determines that the torsion of the drive shaft 24 has not been resolved, and performs step S15. Make a negative judgment in processing. The twist cancellation determination value Tthb can be set to a value smaller than the output torque Tm of the motor generator 20 by a predetermined value, for example. When the motor control unit 631 makes a negative determination in the process of step S15, the process returns to the process of step S13. Therefore, the motor control unit 631 continues to perform the twist elimination torque control in step S14.

On the other hand, if the detected torque value Td of the drive shaft 24 is less than the torsion elimination determination value Tthb, the motor control unit 631 determines that the torsion of the drive shaft 24 has been eliminated, and makes an affirmative determination in the process of step S15. Make a judgment. In this case, the motor control unit 631 ends the series of processes shown in FIG. Therefore, after a predetermined cycle has elapsed, the motor control unit 631 executes the process shown in FIG. 3 again, thereby restarting the basic torque control in step S11.

Next, an example of the operation of the vehicle 10 of this embodiment will be described with reference to FIG. 4.
If the drive wheels 11 and 12 run onto a step at time t10 as shown in FIG. When the torque is reached, the motor control unit 631 determines that the drive shaft 24 is twisted. Therefore, after time t11, the final torque command value T* is set to the corrected torque command value (Tb*-ΔT), so the final torque command value T* gradually decreases as shown by the dashed line. Since the actual output torque Tm of the motor generator 20 changes to follow the change in the final torque command value T*, the actual output torque Tm of the motor generator 20 also gradually decreases as shown by the solid line.

As the actual output torque Tm of the motor generator 20 decreases, the torque that causes twisting is released from the drive shaft 24 before the drive shaft 24 is completely twisted by the negative torque transmitted from the drive wheels 11 and 12. be removed. Therefore, it is possible to prevent the drive shaft 24 from being completely twisted, and therefore vibrations of the vehicle 10 caused by the twist of the drive shaft 24 can be suppressed.

After that, when the driving wheels 11 and 12 cross the step at time t12, the negative torque applied to the driving wheels 11 and 12 is removed, so that the detected torque of the drive shaft 24 is Td decreases rapidly towards its original value. As a result, the deviation ΔT decreases, so the final torque command value T* set as the corrected torque command value (Tb*−ΔT) increases after time t12. Thereafter, when the detected torque value Td of the drive shaft 24 reaches the twist elimination determination value Tthb at time t13, the motor control unit 631 determines that the twist of the drive shaft 24 has been eliminated. Therefore, after the final torque command value T* changes stepwise toward the basic torque command value Tb* at time t13, the final torque command value T* is maintained at the basic torque command value Tb*. Actual output torque Tm of motor generator 20 changes as shown by the solid line to follow this change in final torque command value T*.

According to the control device 60 for the vehicle 10 of the present embodiment described above, the functions and effects shown in (1) to (5) below can be obtained.
(1) The motor control unit 631 determines the detected torque value Td of the drive shaft 24 from the detected torque values Tda and Tdb of the torque sensors 51 and 52. Furthermore, in the process of step S13 shown in FIG. Calculate the final torque command value T*. Then, in the process of step S14, control device 60 executes twist elimination torque control that causes estimated output torque Tm of motor generator 20 to follow final torque command value T*. That is, motor control unit 631 controls motor generator 20 based on detected torque values Tda, Tdb and output torque Tm of motor generator 20. According to this configuration, since the motor generator 20 can be controlled so that the torque that causes twisting is removed from the drive shaft 24, it is possible to avoid completely twisting the drive shaft 24. As a result, vibrations of the vehicle 10 caused by the torsion of the drive shaft 24 can be suppressed.

(2) Assuming that the output signals of the torque sensors 51 and 52 are input to the EV-ECU 62, the motor control unit 631 acquires information on the torque detection values Tda and Tdb of the torque sensors 51 and 52 from the EV-ECU 62. That will happen. In the case of this configuration, a time delay occurs from the time when torque is detected by the torque sensors 51 and 52 until the motor control unit 631 acquires information about that torque. In this regard, in the control device 60 of this embodiment, the output signals of the torque sensors 51 and 52 are directly input to the motor control section 631. According to this configuration, the motor control unit 631 acquires the torque detection values Tda and Tdb of the torque sensors 51 and 52 earlier than a configuration in which the output signals of the torque sensors 51 and 52 are input to the EV-ECU 62. Therefore, control responsiveness can be improved.

(3) The torque calculation section 630 and the motor control section 631 are installed in the MG-ECU 63, which is made up of one microcomputer. According to this configuration, the configuration can be simplified compared to a case where the torque calculation section 630 and the motor control section 631 are each mounted on two different microcomputers.

(4) The motor control unit 631 sets the torsion determination value Ttha based on the output torque Tm of the motor generator 20, and also sets the torsion determination value Ttha for the drive shaft 24 based on the comparison between the detected torque value Td of the drive shaft 24 and the torsion determination value Ttha. Detects the twist of the According to this configuration, torsion of the drive shaft 24 can be detected more accurately.

(5) When the motor control unit 631 detects twisting of the drive shaft 24, the motor control unit 631 corrects the final torque command value T* based on the detected torque value Td of the drive shaft 24. According to this configuration, the output torque Tm of the motor generator 20 can be controlled so that the twist is removed from the drive shaft 24, so that the twist of the drive shaft 24 can be avoided more accurately. As a result, vibrations of the vehicle 10 can be further suppressed.

(First modification)
Next, a first modification of the control device 60 of the first embodiment will be described.
As shown in FIG. 5, the vehicle 10 of this embodiment further includes a motor generator 70, a differential gear 73, and a drive shaft 74 for driving the right rear wheel 13 and the left rear wheel 14. Motor generator 70 is driven based on three-phase AC power supplied from inverter device 21 . The driving force of the motor generator 70 is transmitted to the right rear wheel 13 and the left rear wheel 14 via the differential device 73 and the drive shaft 74, thereby rotating the right rear wheel 13 and the left rear wheel 14. Therefore, in the vehicle 10 of this modification, the right rear wheel 13 and the left rear wheel 14 also serve as driving wheels.

Inverter device 21 is separately provided with a circuit that supplies three-phase AC power to motor generator 20 and a circuit that supplies three-phase AC power to motor generator 70. Therefore, motor generator 20 and motor generator 70 each operate independently. Note that the inverter device corresponding to motor generator 20 and the inverter device corresponding to motor generator 70 may be provided separately.

The vehicle 10 is further provided with a torque sensor 53 that detects the torque applied to one end 741 of the drive shaft 74, and a torque sensor 54 that detects the torque applied to the other end 742 of the drive shaft 74. . Torque sensors 53 and 54 output signals corresponding to the detected torque to MG-ECU 63. Therefore, the torque calculation unit 630 of the MG-ECU 63 detects the torque applied to one end 741 of the drive shaft 74 and the torque applied to the other end 742 of the drive shaft 74 based on the output signals of the torque sensors 53 and 54. be able to.

Furthermore, in the process of step S11 shown in FIG. 3, motor control unit 631 sets basic torque command values Tb1* and Tb2* of motor generator 20 and motor generator 70, respectively, based on basic torque command value Tb*. . The motor control unit 631 sets the basic torque command value Tb1* to the first final torque command value T1*, and then performs feedback control to cause the estimated output torque Tm1 of the motor generator 20 to follow the first final torque command value T1*. By executing this, the output torque of the motor generator 20 is controlled. Similarly, the motor control unit 631 sets the basic torque command value Tb2* to the second final torque command value T2*, and then causes the estimated output torque Tm2 of the motor generator 70 to follow the second final torque command value T2*. The output torque of motor generator 70 is controlled by executing feedback control.

Further, when the motor control unit 631 makes an affirmative determination in the process of step S12 shown in FIG. Find torque command values T1* and T2*. Specifically, the motor control unit 631 calculates each final torque command value T1*, T2* by using the following equations f2, f3.

T1*=Tb1*-ΔT (f2)
T2*=Tb2*+ΔT (f3)
Motor control unit 631 controls the output torque of motor generators 20 and 70 using these final torque command values T1* and T2*.

According to this configuration, even if the output torque of one motor generator 20 is reduced in order to eliminate twisting of the drive shaft 24, the torque corresponding to the reduction is output from the other motor generator 70. become. Therefore, since the running torque of the vehicle 10 as a whole does not decrease, changes in the acceleration of the vehicle 10, etc. can be suppressed. Therefore, it is possible to suppress the vibration of the vehicle 10 caused by the torsion of the drive shaft 24, and to reduce the discomfort felt by the occupants of the vehicle 10.

(Second modification)
Next, a second modification of the control device 60 of the first embodiment will be described.
As shown in FIG. 6, the motor control unit 631 of this embodiment performs the process of step S16 following step S14, by controlling the wheel speed ωw11 of the drive wheels 11, 12 detected by the wheel speed sensors 41, 42, It is determined whether both ωw12 are equal to or higher than a predetermined speed. The predetermined speed is set to a value that allows it to be determined, for example, whether the wheel speeds ωw11 and ωw12 are zero or exhibit values near zero.

If the wheel speeds ωw11 and ωw12 are both equal to or higher than the predetermined speed, the motor control unit 631 makes an affirmative determination in step S16. In this case, the motor control unit 631 determines that the drive wheels 11 and 12 can overcome the step, and executes the processes from step S15 onwards. As a result, in a situation where the drive wheels 11 and 12 can overcome the step, the twist elimination torque control shown in step S14 is continuously executed, so that vibrations of the vehicle 10 can be suppressed.

On the other hand, if at least one of the wheel speeds ωw11 and ωw12 is less than the predetermined speed, the motor control unit 631 makes a negative determination in the process of step S16. In this case, the motor control unit 631 determines that the drive wheels 11 and 12 cannot overcome the step, and temporarily ends the process shown in FIG. 6. In this case, even if the twist elimination torque control shown in step S14 is being executed, the process shown in FIG. Control is executed. That is, when the drive wheels 11 and 12 cannot overcome the step, the control of the motor generator 20 shifts from the twist elimination torque control to the basic torque control. As a result, the final torque command value T* returns to the basic torque command value Tb* from the calculated value of the above formula f1, so that the torque transmitted to the drive wheels 11 and 12 increases. Therefore, the driving wheels 11 and 12 can easily get over the step.

Note that when the motor control unit 631 shifts the control of the motor generator 20 from the twist elimination torque control to the basic torque control, the motor control unit 631 uses filtering processing to control the final output torque Tm so that the output torque Tm of the motor generator 20 does not change stepwise. The torque command value T* may be changed smoothly.

<Second embodiment>
Next, the control device 60 of the vehicle 10 according to the second embodiment will be explained. Hereinafter, the differences between the control device 60 of the first embodiment will be mainly explained.
When the motor control unit 631 of the first embodiment detects the torsion of the drive shaft 24, it sets the final torque command value T* to the corrected torque command value (Tb*−ΔT), and then sets the final torque command value T* to the corrected torque command value (Tb*−ΔT). The output torque Tm of the motor generator 20 was controlled based on the value T*. In such a configuration, if the frequency component of the final torque command value T* includes the resonance frequency of the drive shaft 24, there is a possibility that the drive shaft 24 will resonate and the vibrations of the vehicle 10 will be amplified. be.

Therefore, the control device 60 of this embodiment suppresses the resonance of the drive shaft 24 by removing the resonance frequency component of the drive shaft 24 from the frequency component of the final torque command value T*.
Specifically, as shown in FIG. 7, the motor control section 631 further includes a frequency component extraction section 631a and a filter section 631b.

The output signals of the torque sensors 51 and 52 are input to the frequency component extraction section 631a. The frequency component extraction unit 631a extracts the frequency components of the output signals of the torque sensors 51 and 52 when an affirmative determination is made in step S12 shown in FIG. 3, that is, when twisting of the drive shaft 24 is detected. At the same time, information on the extracted frequency components is transmitted to the filter section 631b. As a method for extracting the frequency components of the output signals of the torque sensors 51 and 52, for example, fast Fourier transform (FFT) can be used. The torque detected by the torque sensors 51 and 52 is the torque applied to the drive shaft 24. Therefore, if the drive shaft 24 vibrates due to torsion, the output signals of the torque sensors 51 and 52 also vibrate. That is, there is a correlation between the frequency of vibration of the drive shaft 24 and the frequency of vibration of the torque sensors 51 and 52. Therefore, the frequency component of the vibration of the drive shaft 24 can be extracted by extracting the frequency component of the output signals of the torque sensors 51 and 52 using the frequency component extraction section 631a.

The filter section 631b receives the frequency component information transmitted from the frequency component extraction section 631a, and also receives the final torque command value T*. The filter section 631b performs filtering processing based on a notch filter on the final torque command value T* based on the frequency component information transmitted from the frequency component extraction section 631a.

Specifically, the filter section 631b determines that among the frequency components transmitted from the frequency component extraction section 631a, a frequency component whose power spectrum is equal to or greater than a predetermined value is the resonant frequency of the drive shaft 24. After identifying the resonance frequency of the drive shaft 24 in this manner, the filter section 631b performs filtering processing on the final torque command value T* based on a notch filter that attenuates the identified resonance frequency.

According to the control device 60 for the vehicle 10 of the present embodiment described above, it is possible to further obtain the operation and effect shown in (6) below.
(6) Since the resonance frequency component of the drive shaft 24 is removed from the frequency component of the final torque command value T*, when torque corresponding to the final torque command value T* is transmitted from the motor generator 20 to the drive shaft 24 Even in this case, resonance of the drive shaft 24 can be suppressed. Therefore, vibrations of the vehicle 10 caused by resonance of the drive shaft 24 can be suppressed.

<Other embodiments>
Note that each embodiment can also be implemented in the following forms.
- As a device for transmitting torque to the driving wheels 11 and 12, for example, as shown in FIG. 8, an integrated device 80 in which a motor generator 20, an inverter device 21, a speed reducer 25, and torque sensors 51 and 52 are modularized is used. may also be used.

- The torsion determination value Ttha used in the process shown in step S12 in FIG. 3 and the torsion elimination determination value Tthb obtained in the process in step S15 may be set to the same value.
- The torque sensors 51 and 52 may be provided in the torque transmission path from the drive shaft 24 to the drive wheels 11 and 12. Such a torque transmission path includes, for example, a hub provided between the drive shaft 24 and the drive wheels 11 and 12.

- The vehicle 10 shown in FIG. 1 may be provided with only one of the torque sensors 51 and 52. Further, the vehicle 10 shown in FIG. 5 may be provided with only one of the torque sensors 51 and 52, and may be provided with only one of the torque sensors 53 and 54.

-Each ECU 61 to 63 and its control method described in the present disclosure are provided by configuring a processor and memory programmed to execute one or more functions embodied by a computer program. Alternatively, it may be realized by multiple dedicated computers. Each ECU 61-63 and its control method described in this disclosure may be implemented by a dedicated computer provided by configuring a processor that includes one or more dedicated hardware logic circuits. Each of the ECUs 61 to 63 and the control method thereof described in the present disclosure are configured by a combination of a processor and memory programmed to execute one or more functions and a processor including one or more hardware logic circuits. It may be implemented by one or more dedicated computers. A computer program may be stored as instructions executed by a computer on a computer-readable non-transitory tangible storage medium. Dedicated hardware logic circuits and hardware logic circuits may be implemented by digital circuits that include multiple logic circuits, or by analog circuits.

- The present disclosure is not limited to the above specific examples. Design changes made by those skilled in the art to the specific examples described above are also included within the scope of the present disclosure as long as they have the characteristics of the present disclosure. The elements included in each of the specific examples described above, as well as their arrangement, conditions, shapes, etc., are not limited to those illustrated, and can be changed as appropriate. The elements included in each of the specific examples described above can be appropriately combined as long as no technical contradiction occurs.

10: Vehicle 11: Right front wheel (drive wheel)
12: Left front wheel (drive wheel)
13: Right rear wheel (drive wheel)
14: Left rear wheel (drive wheel)
20, 70: Motor generator (electric motor)
24, 74: Drive shaft 51, 52, 53, 54: Torque sensor 60: Control device 63: MG-ECU (microcomputer)
80: Integrated equipment 630: Torque calculation section 631: Motor control section 631a: Frequency component extraction section 631b: Filter section

Claims (9)

A control device that controls an electric motor (20, 70) that transmits torque to drive wheels (11, 12, 13, 14) of a vehicle (10),
a torque sensor (51, 52, 53, 54) that detects torque applied to a drive shaft (24, 74) that transmits the torque of the electric motor to the drive wheels;
a motor control unit (631) that controls the electric motor based on a final torque command value ;
The motor control section includes:
determining whether or not the drive shaft is twisted;
If it is determined that the drive shaft is not twisted, setting a basic torque command value transmitted from a higher-level control device to the final torque command value;
If it is determined that the drive shaft is twisted, the basic torque command value is corrected based on the torque detected by the torque sensor, and the corrected torque command value is set as the final torque command value. do
Vehicle control device. The vehicle control device according to claim 1, wherein the torque sensor is provided on the drive shaft or on a torque transmission path from the drive shaft to drive wheels. The vehicle control device according to claim 1 or 2, wherein the output signal of the torque sensor is directly input to the motor control section. further comprising a torque calculation unit (630) that calculates the torque applied to the drive shaft based on the output signal of the torque sensor,
The vehicle control device according to claim 3, wherein the torque calculation section and the motor control section are installed in one microcomputer (63). The vehicle control device according to any one of claims 1 to 4, wherein the electric motor and the torque sensor are modularized as one device (80). The motor control unit determines whether or not the drive shaft is twisted based on the torque detected by the torque sensor and the output torque of the electric motor.
A vehicle control device according to any one of claims 1 to 5. The motor control section includes:
Executing feedback control to cause the output torque of the electric motor to follow the final torque command value.
The vehicle control device according to claim 6. The motor control section includes:
a frequency component extractor (631a) that extracts a frequency component of the output signal of the torque sensor when twisting of the drive shaft is detected;
The vehicle control device according to claim 7, further comprising a filter section (631b) that performs a filtering process on the final torque command value to attenuate the frequency component extracted by the frequency component extraction section. A program for controlling an electric motor (20, 70) that transmits torque to drive wheels (11, 12, 13, 14) of a vehicle (10),
At least one processing unit (63),
detecting the torque applied to the drive shaft (24, 74) that transmits the torque of the electric motor to the drive wheel;
controlling the electric motor based on a final torque command value;
determining whether or not the drive shaft is twisted;
If it is determined that the drive shaft is not twisted, the basic torque command value transmitted from the host control device is set to the final torque command value;
If it is determined that the drive shaft is twisted, the basic torque command value is corrected based on the torque applied to the drive shaft, and the corrected torque command value is set to the final torque command value.
program.

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