JP6350003B2 - Vehicle control device - Google Patents

Description

  The present invention relates to a control device for suppressing pitching in a vehicle including a drive source that independently drives front wheels and rear wheels.

  Conventionally, in a vehicle in which front wheels and rear wheels can be driven independently, the driving force generated on the front wheels and the driving generated on the rear wheels according to the acceleration / deceleration state of the vehicle in order to suppress the pitching that occurs during acceleration / deceleration. Techniques for controlling force have been proposed. For example, in the technique described in Patent Document 1, the longitudinal acceleration acting on the vehicle and the vertical displacement from the reference position in the longitudinal direction of the vehicle body are detected, and the front wheel is determined according to the vertical displacement in the longitudinal direction of the vehicle during acceleration / deceleration of the vehicle. The driving force of both and / or the rear wheel is controlled. Thereby, it is supposed that the vertical displacement can be sufficiently suppressed and the riding comfort of the vehicle can be improved.

  For example, in the technique described in Patent Document 2, in a vehicle in which the distribution of driving force can be changed between the front wheels and the rear wheels, when there is a change in the load on the springs of the suspension device for the front wheels and the rear wheels, The front-rear drive torque distribution ratio is changed so that the fluctuation of the sprung load becomes as small as possible. In this technique, the drive torque distribution ratio is calculated using the instantaneous rotation center angle of the front wheel suspension and the instantaneous rotation center angle of the rear wheel suspension.

Japanese Patent No. 4557157 Japanese Patent No. 4887771

  However, in the case of the technique disclosed in Patent Document 1, the acceleration / deceleration state of the vehicle is determined, and the front and rear driving forces are increased or decreased according to the detection results of the vehicle height sensors provided on the front side and the rear side. Therefore, driving force control for suppressing pitching is performed after the vehicle front-rear position of the vehicle is actually displaced up and down. In the case of the technique disclosed in Patent Document 2 as well, for example, when it is determined that pitching has occurred based on the pitch angle or pitch rate of the vehicle detected from the pitch angle sensor, driving force control for suppressing pitching is performed. Has been done. Even techniques such as Patent Documents 1 and 2 described above can contribute to the suppression of pitching behavior, but in order to further improve the ride comfort, catching the beginning of the pitching behavior and starting the behavior It is desirable to suppress pitching in accordance with the timing.

  One of the objects of the present invention was devised in view of the above-described problems, and provides a vehicle control device that can control the pitching behavior of the vehicle and improve the ride comfort of the occupant. That is. The present invention is not limited to this purpose, and is a function and effect derived from each configuration shown in the embodiments for carrying out the invention described later, and other effects of the present invention are to obtain a function and effect that cannot be obtained by conventional techniques. Can be positioned.

(1) The vehicle control device disclosed herein is a vehicle control device including at least two drive sources that independently drive the front wheels and the rear wheels. The control device is configured to calculate a target drive torque of the vehicle based on a driving operation of a driver, and according to a differential value of the target drive torque calculated by the calculation unit, A drive torque control unit that changes a distribution of the drive torque applied to the rear wheels, the drive torque control unit, when the accelerator is off and the sign of the target drive torque of the vehicle is positive, and when the accelerator is on and the When the sign of the target driving torque of the vehicle is negative, the distribution change is prohibited. The target drive torque of the vehicle includes a positive target drive torque for driving the vehicle and a negative target drive torque (target regeneration torque) for braking the vehicle.

(2) It is preferable that the driving operation of the driver is an accelerator pedal operation and / or a brake pedal operation (at least one of an accelerator pedal operation and a brake pedal operation) .

( 3 ) The drive torque control unit may calculate the drive torque distribution change amount when changing the distribution as a value obtained by multiplying a differential value of the target drive torque calculated by the calculation unit by a predetermined coefficient. Is preferred .

( 4 ) It is preferable that the control device further includes a lateral acceleration sensor that detects a lateral acceleration of the vehicle. In this case, it is preferable that the drive torque control unit prohibits the change of the distribution when the actual lateral acceleration detected by the lateral acceleration sensor is a predetermined value (for example, a predetermined lateral acceleration) or more.

( 5 ) It is preferable that the control device further includes a vehicle speed sensor that detects a vehicle speed of the vehicle and a steering angle sensor that detects a steering angle of the steering wheel. In this case, the drive torque control unit calculates the estimated lateral acceleration of the vehicle based on the vehicle speed detected by the vehicle speed sensor and the steering angle detected by the steering angle sensor, and calculates the absolute value of the estimated lateral acceleration. And the absolute value of the actual lateral acceleration is preferably selected as the selected lateral acceleration, and the change of the distribution is prohibited when the selected lateral acceleration is equal to or greater than a predetermined value.

( 6 ) Preferably, when the selected lateral acceleration is less than the predetermined value, the drive torque control unit gradually decreases the distribution change amount as the selected lateral acceleration increases.
( 7 ) When the selected lateral acceleration is less than a first predetermined value, the drive torque control unit sets a dead zone for changing the distribution with the distribution change amount, and the selected lateral acceleration is greater than or equal to a second predetermined value. The distribution change is prohibited, and when the selected lateral acceleration is greater than or equal to the first predetermined value and less than the second predetermined value, the distribution is changed by an allocation change amount corresponding to the selected lateral acceleration. Is preferred.

According to the disclosed vehicle control device, by changing the distribution of the drive torque applied to the front wheels and the drive torque applied to the rear wheels according to the differential value of the target drive torque, the pitching is performed in accordance with the beginning of the pitching behavior. Therefore, the ride comfort of the occupant can be improved. Moreover, an excessive change in the drive torque distribution can be suppressed.

1 is a schematic block diagram illustrating an overall configuration of a vehicle control device according to an embodiment. It is a block block diagram of the control apparatus of FIG. It is an example of the control block diagram by the control apparatus of FIG. It is a typical left view of the vehicle which can apply the control apparatus of FIG. It is a flowchart which illustrates the control procedure implemented with the control apparatus of the vehicle which concerns on one Embodiment. It is a time chart for demonstrating the effect | action in the control apparatus of the vehicle which concerns on one Embodiment, (a) is accelerator operation, (b) is brake operation, (c) is total demand torque, (d) is total demand torque. (E) shows the torque distribution change amount, and (f) shows the instruction torque to the front and rear motors.

  Embodiments of the present invention will be described below with reference to the drawings. Note that the embodiment described below is merely an example, and there is no intention to exclude various modifications and technical applications that are not explicitly described in the following embodiment. Each configuration of the following embodiments can be implemented with various modifications without departing from the spirit thereof, and can be selected as necessary or can be appropriately combined.

[1. overall structure]
A vehicle control apparatus according to the present embodiment will be described with reference to FIGS. FIG. 1 is a schematic block configuration diagram of a vehicle including a control device according to the present embodiment. As shown in FIG. 1, the vehicle 1 includes a front motor 3f (electric motor, drive source) that drives the front wheels 2f, and a rear motor 3r (electric motor, drive source) that drives the rear wheels 2r, and includes the front wheels 2f and the rear wheels. It is an electric vehicle (electric vehicle) that can drive 2r independently.

  The front and rear motors 3f and 3r are motor generators capable of power running operation and regenerative operation such as a three-phase synchronous motor and a three-phase induction motor. The front motor 3f is driven by being supplied after the electric power stored in the drive battery 9 is converted from direct current to alternating current by the front inverter 5f. Similarly, the rear motor 3r is driven by being supplied with electric power stored in the driving battery 9 after being converted from direct current to alternating current by the rear inverter 5r. Further, the front and rear motors 3f, 3r are regeneratively driven (regenerative braking force is generated) by the rotation of the front wheels 2f and the rear wheels 2r, and the generated power is stored in the drive battery 9.

  A transaxle 4f that distributes the drive torque of the front motor 3f to the left and right front wheels 2f is interposed between the front motor 3f and the drive shaft 6f for the front wheels 2f. Similarly, a transaxle 4r that distributes the drive torque of the rear motor 3r to the left and right rear wheels 2r is interposed between the rear motor 3r and the drive shaft 6r for the rear wheel 2r. The left and right front wheels 2f and rear wheels 2r are provided with brake devices 7f and 7r, respectively. The vehicle 1 also includes a brake controller that controls the brake devices 7f and 7r, and a brake system hydraulic pressure that supplies hydraulic pressure to each of the brake devices 7f and 7r independently based on a command from the brake controller. A unit (both not shown) is provided.

  The front wheel 2f and the rear wheel 2r are independently supported by the vehicle 1 by a front suspension 8f and a rear suspension 8r, respectively. The suspensions 8f and 8r are suspension devices that support the weight of the vehicle body and absorb and mitigate vertical vibrations of the front wheels 2f and the rear wheels 2r during traveling, and prevent vibrations from being directly transmitted to the vehicle body. The suspensions 8f and 8r include springs 8fs and 8rs (see FIG. 4) as elastic elements having appropriate softness against vertical vibrations of the front wheels 2f and the rear wheels 2r, and shock absorbers (as illustrated) as appropriate vibration damping elements. Abbreviation) and links.

  As shown in FIG. 4, when the vehicle 1 is viewed from the side, the instantaneous rotation center Cf of the front suspension 8f and the instantaneous rotation center Cr of the rear suspension 8r are the same as the wheel center 2fc of the front wheel 2f and the rear in the front-rear direction. It is located between the wheel center 2rc of the wheel 2r. The instantaneous rotation centers Cf and Cr here mean the center points (virtual points) of the movement of the front wheels 2f and the rear wheels 2r at that moment in the side view of the vehicle 1. Lines Lf and Lr connecting the instantaneous rotation centers Cf and Cr and the wheel centers 2fc and 2fr, respectively, indicate virtual links of the suspension devices 8f and 8r.

  During acceleration / deceleration of the vehicle 1, driving force (driving torque) or regenerative braking force (regenerative torque) is generated on the front wheels 2 f and the rear wheels 2 r, thereby rotating around the axis (so-called Y axis) extending in the left-right direction through the vehicle body center of gravity G. Pitching moment is generated in The suspensions 8f and 8r are set to have a geometry that generates a vertical force on the front wheel 2f and the rear wheel 2r so that a moment in a direction to cancel the moment is generated. Since a downward force (load, gravity) is applied to the front wheel 2f and the rear wheel 2r, the vertical force generated by the driving force or the regenerative braking force is the load originally applied to the front wheel 2f and the rear wheel 2r. Is added to or subtracted from.

  FIG. 4 schematically shows a left side view of the vehicle 1. In FIG. 4, an arrow indicated by a thick solid line indicates a force generated during acceleration, and an arrow indicated by a thick broken line indicates a force generated during deceleration. In the case of acceleration, a driving force Fxf is generated on the front wheel 2f and a driving force Fxr is generated on the rear wheel 2r. As a result, a pitching moment is generated around the Y axis in the vehicle 1, but the suspensions 8f and 8r generate a downward force Fzf on the front wheel 2f and an upward force Fzr on the rear wheel 2r, respectively. It is suppressed.

  In contrast, in the case of deceleration, a regenerative braking force Rxf is generated on the front wheels 2f, and a regenerative braking force Rxr is generated on the rear wheels 2r, respectively. As a result, a pitching moment about the Y-axis is generated in the vehicle 1 in the opposite direction to that during acceleration. However, the suspensions 8f and 8r generate an upward force Rzf on the front wheel 2f and a downward force Rzr on the rear wheel 2r, respectively. In addition, the pitching moment is suppressed.

As shown in FIG. 1, the vehicle 1 includes a vehicle speed sensor 13 that detects a vehicle speed V of the vehicle 1, a lateral acceleration sensor 14 that detects a lateral acceleration Ay _D of the vehicle 1, and an operation amount of the steering wheel 10 by a driver ( Hereinafter, a steering angle sensor 15 for detecting a steering angle θs) is provided. Further, an accelerator opening sensor 16 for detecting the amount of depression of the accelerator pedal 11 by the driver (driving operation, hereinafter referred to as accelerator opening AP) and an operation of the brake pedal 12 by the driver (driving operation, hereinafter referred to as brake operation). A brake switch (sensor) 17 for detecting presence or absence is provided. The detection results (sensor values) from these sensors 13 to 17 are transmitted to the ECU 20 described later.

Lateral acceleration Ay _D detected by the lateral acceleration sensor 14 (hereinafter, referred to as actual lateral acceleration Ay _D) corresponds to the change of course of the vehicle 1, the actual lateral acceleration Ay _D increases the time of turning the vehicle 1, When the vehicle travels substantially straight, the actual lateral acceleration Ay _D decreases. The steering angle θs corresponds to the steering operation direction. The accelerator opening AP corresponds to the magnitude of the output requested by the driver, and the brake operation corresponds to the magnitude of the braking force requested by the driver. That is, when the driver's required output is large (when there is an acceleration request), the accelerator opening AP is large, and when the driver's required output is small (when there is a steady running or deceleration request), the accelerator opening AP is small. . In addition, the brake is operated when the driver requests deceleration.

  The vehicle 1 is provided with an ECU 20 (control device, Electronic Control Unit) configured as an LSI device or an embedded electronic device in which, for example, a microprocessor, ROM, RAM, and the like are integrated. The ECU 20 is an electronic control device that performs integrated control of various devices mounted on the vehicle 1, and is connected to a communication line of an in-vehicle network provided in the vehicle 1. In the present embodiment, drive torque control for suppressing the pitching behavior during acceleration / deceleration of the vehicle 1 will be described.

[2. Control configuration]
The drive torque control is a control that suppresses pitching by changing the distribution of the drive torque applied to the front wheels 2f and the drive torque applied to the rear wheels 2r when the vehicle 1 is accelerated or decelerated. The driving torque referred to here includes negative driving torque, that is, regenerative torque. Hereinafter, when simply referred to as drive torque, it means both positive drive torque and negative drive torque (regenerative torque).

  ECU20 is provided with the calculating part 21 and the drive torque control part 22 as a functional element for implementing the above drive torque control as shown in FIGS. 1-3. Further, the drive torque control unit 22 is provided with a drive torque distribution unit 23, a turning determination unit 24, a drive regeneration determination unit 25, and a torque command unit 26. Each of these elements may be realized by an electronic circuit (hardware), may be programmed as software, or some of these functions are provided as hardware, and the other part is software. It may be a thing.

The calculation unit 21 calculates a target driving force _PT that is a target value of the driving force required for the vehicle 1 based on the driving operation of the driver, and is generated in the front and rear motors 3f and 3r from the target driving force _PT. The driving torque to be generated (that is, the required torque Tf _R of the front motor 3f and the required torque Tr _{R of} the rear motor 3r) is calculated. Note that the target driving force P _T calculated here is also a negative target for braking the vehicle 1 (braking the vehicle 1) in addition to the positive target driving force P _T for driving the vehicle 1. The target driving force P _T is included. The negative target driving force _PT corresponds to the target value of the regenerative braking force. Hereinafter, the term “target driving force P _T ” means both positive and negative target driving force P _T.

As shown in FIG. 3, the calculation unit 21 calculates a target driving force P _T based on the accelerator opening AP (accelerator pedal operation), the brake pedal operation, the vehicle speed V, an external load, and the like, and from the target driving force P _T total required torque T _R (target driving torque, hereinafter referred to as the total required torque T _R) calculates the arithmetic total required torque T around _R so as to satisfy the motor 3f, 3r required torque Tf _R, Tr _R respectively (Ie, T _R = Tf _R + Tr _R ). Here, when the target driving force P _T is a negative value, the required torques T _R , Tf _R , and Tr _R are negative driving torques (that is, regenerative torques).

The required torque Tf _R of the front motor 3f calculated by the calculation unit 21 corresponds to the driving torque applied to the front wheels 2f, and the required torque Tr _R of the rear motor 3r corresponds to the driving torque applied to the rear wheels 2r. That is, it can be said that the calculation unit 21 determines the distribution of the drive torque applied to the front wheels 2f and the drive torque applied to the rear wheels 2r (hereinafter referred to as drive torque distribution) according to the driving operation of the driver. The calculation unit 21 transmits the required torques Tf _R and Tr _R and the total required torque T _R of the front and rear motors 3 f and _{3 r} to the drive torque control unit 22.

Drive torque control unit 22, when a predetermined condition is satisfied, in accordance with the differential value of the total required torque T _R, which is computed by the computing unit 21, a pitching change the driving torque distribution determined by the calculator 21 It is to suppress. As described above, the geometry of the suspensions 8f and 8r is set so as to suppress the occurrence of pitching. However, it is not possible to set the pitch so that the pitching does not occur completely due to other constraints (arrangement, spring constant, etc.). difficult. Therefore, the drive torque control unit 22 distributes the drive torque so that the vertical force is generated in the direction to suppress the pitching in order to suppress the pitching by using the vertical force generated in the front wheel 2f and the rear wheel 2r by the drive torque. change.

  For example, the drive torque control unit 22 increases the positive drive torque of the front wheels 2f so that a large downward force is generated by the front wheels 2f in order to suppress pitching in the direction in which the front wheels 2f rise during acceleration. Accordingly, the drive torque distribution is changed so as to reduce the positive drive torque of the rear wheel 2r. Note that the predetermined condition is that the vehicle 1 is traveling substantially straight (not significantly turning). That is, changing the driving torque distribution in a situation where the traveling direction of the vehicle 1 changes, such as cornering or turning left or right when the vehicle 1 turns a curve may affect the movement of the vehicle 1 in the yaw direction. In this situation, the change of the drive torque distribution is prohibited, and the drive torque distribution is changed only when the vehicle 1 is traveling substantially straight.

Drive torque distribution unit 23, as shown in FIG. 3 and the following equation (1), the total required torque T _R, which is computed by the computing unit 21 differentiates once with time, a predetermined gain K (predetermined coefficient) The multiplied value is calculated as a temporary torque distribution change amount DT (distribution change amount). The gain K is a positive value set in advance. The drive torque distribution unit 23 transmits the calculated temporary distribution change amount DT to the torque command unit 26. The temporary distribution change amount DT transmitted to the torque command unit 26 is added to or subtracted from the required torques Tf _R and Tr _R of the front and rear motors 3f and 3r according to the determination results of the turning determination unit 24 and the drive regeneration determination unit 25. .

To use a differential value of the total required torque T _R to calculate the provisional allocation change amount DT of torque is to capture the change in total required torque T _R (or target driving force P _T). That is, the total required torque T _R are the front and rear in accordance with the timing of the change in the motor 3f, required torque Tf _R of 3r, changes the Tr _R (i.e. to change the driving torque distribution) that is combined at the beginning out of pitching behavior Thus, a vertical force is generated on the front wheel 2f and the rear wheel 2r to improve the feeling of pitching.

  The turning determination unit 24 determines whether or not the predetermined condition is satisfied, and outputs a value in a range from 0 to 1 as a gain Ga according to whether or not the predetermined condition is satisfied. The gain Ga output here is multiplied by the temporary distribution change amount DT in the torque command unit 26 described later. When the gain Ga = 0, the change in the drive torque distribution is invalid (change is prohibited). ).

As shown in FIG. 3, the turning determination unit 24 applies the vehicle speed V detected by the vehicle speed sensor 13 and the steering angle θs detected by the steering angle sensor 15 to the vehicle characteristic map 24a, and estimates the lateral acceleration Ay _E. To do. Next, in the processing unit 24b, the larger value of the absolute value of the estimated lateral acceleration Ay _E (hereinafter referred to as the estimated lateral acceleration Ay _E ) and the absolute value of the actual lateral acceleration Ay _D detected by the lateral acceleration sensor 14 is obtained. Is selected as the selected lateral acceleration Ay, and this selected lateral acceleration Ay is set as an input value to be input to the gain map 24c. Then, the selected lateral acceleration Ay is input to the gain map 24c, and the gain Ga corresponding to the selected lateral acceleration Ay is set.

The vehicle characteristic map 24a is a map in which the relationship among the vehicle speed V, the steering angle θs, and the estimated lateral acceleration Ay _E is set in advance. Instead of using the vehicle characteristic map 24a, the estimated lateral acceleration Ay _E may be calculated based on the detected vehicle speed V, steering angle θs, and vehicle specifications. The gain map 24c is a map in which the selected lateral acceleration Ay is set on the horizontal axis and the gain Ga is set on the vertical axis. Gain map 24c is selected by the lateral acceleration Ay is less than 0 or more and the first predetermined value Ay ₁ range is set gain Ga 1 second predetermined value Ay is selected lateral acceleration Ay greater than the first predetermined value Ay _{1 In} the range of ₂ or more, the gain Ga is set to 0. Further, in the range where the selected lateral acceleration Ay is not less than the first predetermined value Ay ₁ and less than the second predetermined value Ay ₂ , the gain Ga is set so as to approach 1 to 0 as the selected lateral acceleration Ay increases. .

Turning decision unit 24, by using the thus set gain map 24c, if the selected lateral acceleration Ay smaller than the first predetermined value Ay _1, the vehicle 1 is not turning large (predetermined condition is satisfied ) And set the gain Ga to 1. That is, if the selected lateral acceleration Ay smaller than the first predetermined value Ay ₁ sets a dead zone to maintain the gain Ga to 1. The turning determination unit 24 determines that the vehicle 1 is turning (does not satisfy the predetermined condition) when the selected lateral acceleration Ay is equal to or greater than the second predetermined value Ay ₂ (predetermined value, predetermined lateral acceleration). Set the gain Ga to 0.

If the selected lateral acceleration Ay is greater than or equal to the first predetermined value Ay _{1 and} less than the second predetermined value Ay _{2, the} gain Ga is set to a value closer to 0 as the selected lateral acceleration Ay increases (that is, the selected lateral acceleration Ay The gain Ga is set so as to gradually decrease the influence of the temporary distribution change amount DT in accordance with the increase in the amount of increase in the drive torque distribution, thereby gradually invalidating the change in the drive torque distribution. By setting in this way, the influence of the temporary distribution change amount DT of the drive torque gradually decreases according to the steering operation. For example, it is possible to suppress a rapid torque change of the front and rear wheels with respect to a change in the steering angle θs, for example. it can. The turning determination unit 24 transmits the set gain Ga to the torque command unit 26.

Driving regeneration determination section 25, based on the sign of the accelerator pedal opening AP and the total required torque T _R, in which the front and rear of the motor 3f, 3r to determine whether the driving state or regeneration state. The drive regeneration determination unit 25 outputs a value of 0, 1 or −1 as the gain Gb according to the operating state of the motors 3f and 3r. The gain Gb output here is multiplied by the multiplication value of the temporary distribution change amount DT and the gain Ga in the torque command unit 26 described later. When the gain Gb = 0, the change in the drive torque distribution is invalid. (Changes are prohibited).

The determination by the drive regeneration determination unit 25 is for determining whether the temporary distribution change amount DT calculated by the drive torque distribution unit 23 is added to the front wheel 2f side or the rear wheel 2r side. Drive torque allocation, the total required torque T and is altered in accordance with the differential value of _R, since the pitching direction is reversed at the time of driving and the time of regeneration, outputs a gain Gb corresponding to the operating state of the motor 3f, 3r By doing so, the torque distribution change direction is changed. Here, the torque distribution change from the rear to the front is the forward direction.

As shown in FIG. 3, the drive regeneration determination unit 25 includes two switches 25a and 25b. The switch 25a outputs 1 when the accelerator opening AP inputted is larger than 0 (when the accelerator is on), and outputs -1 when the accelerator opening AP is 0 (when the accelerator is off). The switch 25b is the sign of the total required torque T _R to be input is for positive outputs 1, the sign of the total required torque T _R is for negative outputs -1. Then, the drive regeneration determination unit 25 sets a value obtained by multiplying the value obtained by adding the output values from the two switches 25a and 25b by 0.5 as the gain Gb.

Therefore, the driving regeneration determination section 25, the sign of the accelerator-on and total required torque T _R is for positive, the motor 3f, 3r is set to 1 the gain Gb is determined that the driving state. Also, if the sign is negative accelerator pedal and the total required torque T _R, the motor 3f, 3r is set to -1 gain Gb is determined that the regeneration state. When these non, that if the sign is negative accelerator-on and total required torque T _R, and the sign of the accelerator pedal and the total required torque T _R is for positive, the gain Gb is set to 0. The drive regeneration determination unit 25 transmits the set gain Gb to the torque command unit 26.

  Based on the information transmitted from the drive torque distribution unit 23, the turning determination unit 24, and the drive regeneration determination unit 25, the torque command unit 26 indicates instruction torques Tf, Tr (torque command values) to be instructed to the front and rear motors 3f, 3r. ) Is set and output. As shown in FIG. 3, the torque command unit 26 first multiplies the temporary distribution change amount DT and the gain Ga, and further multiplies the multiplied value by the gain Gb to calculate the torque distribution change amount ΔT. This torque distribution change amount ΔT is a distribution change amount according to the selected lateral acceleration Ay.

For the front motor 3f, a value obtained by adding the torque distribution change amount ΔT and the required torque Tf _R is set as the instruction torque Tf. On the other hand, for the rear motor 3r, a value obtained by multiplying the torque distribution change amount ΔT by −1 and adding the required torque Tr _R thereto is set as the instruction torque Tr. The torque command unit 26 instructs the front and rear motors 3f and 3r to set the front and rear instruction torques Tf and Tr, and controls the motors 3f and 3r.

Therefore, when the torque distribution change amount ΔT is positive (that is, when the differential value> 0 and the gain Gb> 0 and the differential value <0 and the gain Gb <0), the drive torque is distributed by ΔT from the rear to the front. Since it is changed, the driving torque of the front motor 3f increases. Therefore, when the motors 3f and 3r are in a driving state (when the total required torque T _R > 0), the positive driving torque of the front wheels 2f increases and the positive driving torque of the rear wheels 2r decreases. On the other hand, when the motors 3f and 3r are in the regenerative state (when the total required torque T _R <0), the negative drive torque (regenerative torque) of the front wheels 2f decreases and the negative drive torque (regenerative torque) of the rear wheels 2r. ) Increases. In other words, in this case, the torque (drive torque) distribution change direction is from the rear to the front, but the rear increases as the absolute value of the torque (regenerative torque).

When the torque distribution change amount ΔT is negative (that is, when the differential value> 0 and the gain Gb <0, and the differential value <0 and the gain Gb> 0), the driving torque is distributed from the front to the rear by ΔT. As a result, the driving torque of the rear motor 3r increases. Therefore, when the motors 3f and 3r are in a driving state (when the total required torque T _R > 0), the positive driving torque of the front wheels 2f decreases and the positive driving torque of the rear wheels 2r increases. On the other hand, when the motors 3f and 3r are in the regenerative state (when the total required torque T _R <0), the negative drive torque (regenerative torque) of the front wheels 2f increases and the negative drive torque (regenerative torque) of the rear wheels 2r. ) Decreases. That is, in this case, the torque (drive torque) distribution change direction is from the front to the rear, but the front increases as the absolute value of the torque (regenerative torque).

In the case of negative case the torque distribution changing amount ΔT positive, the total required torque T _R in the case of performing torque distribution change, is equivalent to the total required torque T _R when not subjected to torque distribution changes. Therefore, the vehicle speed when the torque distribution change is performed is equivalent to the vehicle speed when the torque distribution change is not performed.

Table 1 below summarizes the above contents. Table 1, in the case of four running state A~D in accordance with the differential value of the gain Gb and total required torque T _R based on the sign and the accelerator operation of the total required torque T _R, are performed by the drive torque control unit 22 Indicates the control content. In Table 1, the gain Ga is not 0 (the torque distribution change amount ΔT is not 0). In Table 1, “F” indicates the front and “R” indicates the rear. In the column where the torque distribution change amount ΔT is positive, the drive torque is changed from the rear to the front, and the negative column is from the front to the rear. This means that the drive torque is changed in distribution. “Regenerative torque” corresponds to negative driving torque.

Running state A, the total required torque T code _R is has a positive accelerator operation (or gain Gb> 0), and shows a state differential value is a positive value, the torque distribution changing amount ΔT is positive Therefore, the distribution of the drive torque is changed from the rear to the front. Running state B, the sign of the total required torque T _R is has a positive accelerator operation (or gain Gb> 0), and the differential value indicates the state is a negative value, the torque distribution changing amount ΔT is negative Therefore, the distribution of the driving torque is changed from the front to the rear.

Running state C, total required sign of the torque T _R is no accelerator operation a negative (or gain Gb <0), and the differential value indicates the state is a negative value, the torque distribution changing amount ΔT is positive Therefore, the distribution of the drive torque is changed from the rear to the front. Running state D, the total required torque T _R code no accelerator operation a negative (or gain Gb> 0), and shows a state differential value is a positive value, the torque distribution changing amount ΔT is negative Therefore, the distribution of the driving torque is changed from the front to the rear.

[3. flowchart]
FIG. 5 is a flowchart for explaining an example of the procedure of drive torque control. This flowchart is repeatedly executed at a predetermined calculation cycle when the power source of the ECU 20 is on.
As shown in FIG. 5, in step S <b> 10, various information detected by the various sensors 13 to 17 is input to the ECU 20. In step S20, the target driving force P _T is calculated in the calculator 21, the total required torque T _R and around the motor 3f on the basis of the target driving force P _T, required torque Tf _R of 3r, and the Tr _R is calculated The

In step S30, the drive torque distribution unit 23, the temporary allocation change amount DT of the torque, is calculated total required torque T _R computed in the previous step as the value obtained by multiplying the gain K to a differentiated once time. In subsequent step S40, it is determined whether or not the predetermined condition is satisfied in the turning determination unit 24 (the turning determination of the vehicle 1 is performed). Here, the larger value of the absolute value of the actual lateral acceleration Ay _{D and} the absolute value of the estimated lateral acceleration Ay _E is selected as the selected lateral acceleration Ay, and this selected lateral acceleration Ay is the first predetermined value Ay ₁ , the second It is compared with a predetermined value Ay _2, is output gain Ga in accordance with the selected lateral acceleration Ay. If the gain Ga is not 0, the vehicle is not turning (substantially straight), so the process proceeds to step S50. If the gain Ga is 0, the vehicle is turning, and the process returns to this flowchart.

In step S50, the drive regeneration determination unit 25 determines whether the motors 3f and 3r are in a drive state or a regeneration state. Here, the sign of the accelerator-on and total required torque T _R is for positive is determined to be in the driving state, the sign of the accelerator pedal and the total required torque T _R is for negative is determined that the regeneration state. If it is in any state, the process proceeds to step S60, and if it is not in any state, this flowchart is returned.

  In step S60, the torque command unit 26 multiplies the temporary distribution change amount DT calculated by the drive torque distribution unit 23 by the gain Ga output by the turning determination unit 24 and the gain Gb output by the drive regeneration determination unit 25. The calculated value is calculated as the torque distribution change amount ΔT. In step S70, the torque command unit 26 changes the torque distribution according to the torque distribution change amount ΔT calculated in the previous step, and sets and outputs the instruction torques Tf and Tr of the front and rear motors 3f and 3r. .

[4. Action]
FIGS. 6A to 6F are time charts for explaining the drive torque control by the present control device. The four running states A to D in Table 1 and the gain Gb are set to zero. Indicates the running state. Here, it is assumed that the vehicle 1 is traveling straight (a gain Ga is always 1), and the calculation unit 21 calculates the required torques Tf _R and Tr _R of the front and rear motors 3f and 3r as the same value. to (i.e., based on the time differential value is 0 the total required torque T _R sometimes a one to one ratio of drive torque distribution at baseline) intended to. For example, if the zero torque distribution change amount [Delta] T, the command torque Tr of indicated torque Tf and the rear motor 3r of the front motor 3f are all the half value of the total required torque T _R.

As shown in FIG. 6 (a), (c) and (d), when the accelerator operation of the driver is input at time t _0, since the total required torque T _R is increased along with this, the total required torque T The differential value of _R increases from zero. If the accelerator operation is constant, the differential value is the total required torque T _R becomes a positive value to a constant at time t _1, at time t ₁ becomes zero. From time t ₀ to t ₁ corresponds to the traveling state A in Table 1 above. That is, the sign of the accelerator-on and total required torque T _R is positive, the gain Gb is 1 is output, thereby as shown in FIG. 6 (e), predetermined gain K on the differential value, multiplied by Ga and Gb The torque distribution change amount ΔT, which is the calculated value, becomes a positive value.

In other words, the driving torque to the front is changed allocated from the rear by the torque distribution changing amount ΔT from the torque distribution at the reference time (moved), as shown in FIG. 6 (f), the time from immediately after the time t ₀ t Until it becomes ₁ , the instruction torque Tf of the front motor 3f is set larger than the instruction torque Tr of the rear motor 3r. As a result, the positive driving torque applied to the front wheels 2f is increased more than the positive driving torque applied to the rear wheels 2r, and the pitching behavior during acceleration in the driving state is suppressed.

FIG. 6 (a), the as shown in (c) and (d), the time at t _2, when it is in the state of the accelerator-on is smaller than accelerator pedal opening AP until then, total required torque T in accordance with this _{since R} is reduced, the differential value of the total required torque T _R is reduced from 0. If the accelerator operation is constant, the differential value is the total required torque T _R becomes a negative value to a constant at time t _3, the time t ₃ at 0. From time t ₂ to t ₃ corresponds to the traveling state B in Table 1 above. That is, the sign of the accelerator-on and total required torque T _R is positive, the gain Gb is 1 is output, thereby as shown in FIG. 6 (e), predetermined gain K on the differential value, multiplied by Ga and Gb The torque distribution change amount ΔT, which is the value obtained, is a negative value.

That is, the drive torque is changed from the rear to the front by the torque distribution change amount ΔT from the reference torque distribution (in other words, the drive torque is changed from the front to the rear by the absolute value of the torque distribution change amount ΔT). . Therefore, as shown in FIG. 6 (f), during the period from immediately after the time t ₂ until time t _3, indicated torque Tf of the front motor 3f is set smaller than the command torque Tr of the rear motor 3r. Thus, a positive driving torque applied to the rear wheel 2r is increased than the positive driving torque applied to the front wheel 2f, the pitching behavior when positive total required torque T _R is reduced during driving is suppressed.

FIG. 6 (a), the as shown in (c) and (d), when the accelerator operation is 0 (accelerator OFF) at time t _4, since the total required torque T _R is reduced along with this, the total required torque The derivative value of T _R decreases from zero. If left accelerator-off, the differential value is the total required torque T _R becomes a negative value to a constant at time t _6, the 0 at time t _6. Here, during the period from time t ₄ to time t ₅ the total required torque T _R becomes 0, the sign of the accelerator pedal and the total required torque T _R is for positive, the gain Gb is 0 is output. That is, as shown in FIG. 6 (e), between the time t ₄ to t ₅ is next zero torque distribution change amount [Delta] T, the change of the driving torque distribution is prohibited. In other words, the change in the drive torque distribution is invalidated in the transient state from drive to regeneration.

Also, during the period from time t ₅ to t ₆ corresponds to the traveling state C in Table 1 above. That is, the sign is negative accelerator pedal and the total required torque T _R, the gain Gb is output -1, thereby as shown in FIG. 6 (e), predetermined gain K on the differential value, the Ga and Gb The torque distribution change amount ΔT, which is a multiplied value, is a positive value. That is, since the driving torque is changed from the rear to the front by the torque distribution change amount ΔT from the torque distribution at the reference time, as shown in FIG. 6 (f), from immediately after time t ₅ until time t ₆ is reached. Meanwhile, the instruction torque Tf of the front motor 3f is set larger than the instruction torque Tr of the rear motor 3r. In other words, the regenerative torque of the rear motor 3r is set larger than the regenerative torque of the front motor 3f. Thereby, the negative drive torque (regenerative torque) given to the rear wheel 2r is increased more than the negative drive torque (regenerative torque) given to the front wheel 2f, and the pitching behavior during deceleration in the regenerative state is suppressed.

FIG. 6 (b), the as shown in (c) and (d), the driver of the brake operation is input at time t _7, the total required torque T _R is further reduced with the (target regenerative torque which increasing) order differential value of the total required torque T _R is reduced from 0. If the brake operation is constant, the differential value becomes a negative value to a total required torque T _R becomes constant at time t _8, 0 and becomes at time t _8. From the time t ₇ to t _8, corresponding to the traveling state C in Table 1 above, the gain Gb -1 is output. As a result, as shown in FIG. 6E, the torque distribution change amount ΔT becomes a positive value, and the drive torque is changed from the rear to the front by the torque distribution change amount ΔT from the torque distribution at the reference time.

Accordingly, as shown in FIG. 6 (f), during the period from immediately after the time t ₇ until the time t _8, indicated torque Tf of the front motor 3f is set larger than the command torque Tr of the rear motor 3r. In other words, the regenerative torque of the rear motor 3r is set to be larger than the regenerative torque of the front motor 3f, whereby the negative drive torque (regenerative torque) applied to the rear wheels 2r is negative drive torque (regenerative torque) applied to the front wheels 2f. Torque), and the pitching behavior during deceleration in the regenerative state is suppressed.

FIG. 6 (b), the as shown in (c) and (d), when the brake operation is slightly weakened at time t _9, the total code of the required torque T _R is small absolute value remains negative Along with this comprising (target regenerative torque decreases) Therefore, the differential value of the total required torque T _R increases from zero. If the brake operation is constant, the differential value is the total required torque T _R at time t ₁₀ becomes a positive value to a constant, the time t ₁₀ at 0. From time t ₉ to t ₁₀ corresponds to the traveling state D of Table 1 above. That is, the sign is negative accelerator pedal and the total required torque T _R, the gain Gb is output -1, thereby as shown in FIG. 6 (e), predetermined gain K on the differential value, the Ga and Gb The torque distribution change amount ΔT, which is a multiplied value, is a negative value.

That is, the drive torque is changed from the rear to the front by the torque distribution change amount ΔT from the reference torque distribution (in other words, the drive torque is changed from the front to the rear by the absolute value of the torque distribution change amount ΔT). . Therefore, as shown in FIG. 6 (f), during the period from immediately after the time t ₉ until the time t _10, indicated torque Tf of the front motor 3f is set smaller than the command torque Tr of the rear motor 3r. In other words, the regenerative torque of the front motor 3f is set larger than the regenerative torque of the rear motor 3r. Thus, than negative drive torque negative driving torque applied to the front wheel 2f to (regenerative torque) applied to the rear wheels 2r (regenerative torque) is increased, pitching when a negative total required torque T _R is decreased during regeneration Behavior is suppressed.

[5. effect]
In the control device of the above-described vehicle drive torque according to the differential value of the total required torque T _R as the target driving torque is calculated based on the target driving force P _T, given to the rear wheels 2r and driving torque applied to the front wheel 2f The pitching can be suppressed by using the vertical force generated by the driving torque in accordance with the beginning of the pitching behavior. That is, rather than from the determined pitching occurs to suppress pitching, it is possible to suppress the pitching at the timing to start out behavior, the occupant without changing the total required torque T _R Riding comfort can be improved.

  Moreover, if it is the above-mentioned control apparatus, since it is not necessary to detect a pitching state using sensors, such as a displacement meter and a load meter, an apparatus structure can be simplified. Furthermore, since it is not necessary to solve exact mathematical formulas relating to vehicle motion and suspension geometry, the control configuration can be simplified.

  Heretofore, a method has been considered in which the pitching behavior is estimated using the vehicle body longitudinal acceleration and the vehicle speed, and the pitching is suppressed by changing the front and rear drive torque distribution. Specifically, the pitch angle is obtained by multiplying the value obtained by subtracting the vehicle body acceleration, which is the differential value of the vehicle speed, from the detection value of the longitudinal acceleration sensor by the moment length that is the difference between the height of the longitudinal acceleration sensor and the center of gravity of the vehicle body. Estimate acceleration. And it is the method of changing drive torque distribution according to this estimated pitch angular acceleration.

However, in the case of this method, the detection values of the longitudinal acceleration sensor and the vehicle speed sensor may contain errors due to the influence of disturbances such as slopes and bad roads, and the moment length is sufficiently secured depending on the loading state and vehicle type. There were many issues to adopt. In contrast, the above control device, to change the driving torque distribution in accordance with the differential value of the total required torque T _R that is calculated based on the target driving force P _T, tough against disturbance, performs calculations easier be able to.

In the control device of the above-described vehicle, detects an accelerator pedal operation and a brake pedal operation as a driving operation of the driver, for calculating the total required torque T _R on the basis of these, it is possible to further improve the drive feeling.

Further, in the control apparatus of the above-described vehicle, if the sign is positive accelerator-off and total required torque T _R, and the sign of the accelerator-on and total required torque T _R is for negative gain Gb is 0 is output Change of distribution is prohibited. That is, the driving state and the regenerative state change when the accelerator is off even when the target driving force P _T is a positive value, and when the accelerator is on even when the target driving force P _T is a negative value. The change in the drive torque distribution is invalidated as a transient state. As a result, the drive torque distribution is changed only when the motors 3f and 3r are reliably driven or regenerated, and an excessive change in the drive torque distribution can be suppressed.

In the control device of the above-described vehicle, calculated as a value the provisional allocation change amount DT, multiplied by the predetermined gain K to the differential value of the total required torque T _R based on the target driving force P _T of the driving torque when changing the allocation Therefore, the temporary distribution change amount DT when changing the drive torque distribution can be easily calculated. In addition, since the temporary distribution change amount DT of the driving force is calculated as a value proportional to the differential value of the total required torque T _R , the temporary distribution change amount DT increases as the change in the target driving force P _T increases and the pitching behavior tends to increase. Since the pitch is large, the pitching behavior can be effectively suppressed.

  In the above-described vehicle control device, the temporary distribution change amount DT of the drive torque is changed from one of the front wheels 2f and the rear wheels 2r to the other depending on whether the motors 3f and 3r are in a driving state or a regenerative state. Thus, it is possible to perform appropriate driving torque control according to the traveling state of one.

  In the above-described vehicle control device, the turning performance of the vehicle 1 is determined, and when the traveling direction of the vehicle 1 is changed, the change of the drive torque distribution is prohibited, so that traveling stability can be ensured. . That is, if the front and rear drive torque distribution changes during the turning of the vehicle 1, the movement of the vehicle 1 in the yaw direction and the lateral direction is affected, and the vehicle 1 may not be able to turn stably. By changing the drive torque distribution only when the vehicle is not turning, the pitching behavior can be suppressed while ensuring the running stability.

In this embodiment, in order to determine the turning performance of the vehicle 1, the absolute value of the estimated lateral acceleration Ay _E estimated from the vehicle speed V and the steering angle θs and the actual lateral acceleration Ay _D directly detected by the lateral acceleration sensor 14 are used. Is selected as the selected lateral acceleration Ay, and the selected lateral acceleration Ay is compared with the first predetermined value Ay ₁ and the second predetermined value Ay ₂ . Thereby, determination of vehicle turning can be performed accurately.

In addition, here, since the change of distribution is prohibited when the selected lateral acceleration Ay is equal to or greater than the second predetermined value Ay ₂ , for example, even when the vehicle 1 is drifting, the vehicle 1 is appropriately turned. Gender can be determined. On the other hand, the selection lateral acceleration Ay in the case of less than the second predetermined value Ay _2, is set as the tentative allocation change amount DT is gradually reduced with the increase of the selection lateral acceleration Ay. That is, since the temporary distribution change amount DT of the drive torque gradually decreases according to the steering operation, a sudden torque change of the front and rear wheels can be suppressed.

Furthermore, in the above embodiment, the second predetermined value Ay ₂ providing the first predetermined value Ay ₁ less than (i.e., providing a threshold for turning decision in two steps). When the selected lateral acceleration Ay is less than the first predetermined value Ay ₁ , the gain Ga is set to 1, and a dead zone in which the distribution is changed by the temporary distribution change amount DT is set (the torque distribution change amount ΔT The absolute value is made equal to the temporary distribution change amount DT). Further, the selection lateral acceleration Ay in the case of the second predetermined value Ay ₂ or more, is set to the gain Ga is 0, changing the allocation is prohibited. Further, when the selected lateral acceleration Ay is not less than the first predetermined value Ay ₁ and less than the second predetermined value Ay ₂ , the gain Ga is set according to the selected lateral acceleration Ay, and the distribution change amount according to the selected lateral acceleration Ay The distribution is changed by ΔT. As described above, since the gain map 24c is set so that the gain Ga corresponding to the selected lateral acceleration Ay is set, the change of the drive torque distribution is set to be gradually invalidated. Flexible control according to the state becomes possible.

[6. Others]
Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.
In the above embodiment, the calculation unit 21 calculates the total required torque T _R from the target driving force P _T and changes the drive torque distribution according to the differential value of the total required torque T _R , but the total required torque T _The driving torque distribution may be changed according to the differential value of the target driving force _PT without calculating _R.

Moreover, the control method of the above-mentioned drive torque control part 22 is an example, Comprising: It is not restricted to what was mentioned above. For example, the drive torque distribution unit 23 described above, but calculates the value obtained by multiplying the gain K to the total required torque T _R, which is computed by the computing unit 21 as a tentative allocation change amount DT, the drive torque distribution unit 23 provisionally Instead of calculating the torque as the distribution change amount DT, the pitch angle jerk may be calculated. The pitch angle jerk is a value obtained by differentiating the pitch angle θp centered on the vehicle body center of gravity G shown in FIG. 4 three times and corresponds to jerk. Therefore, pitching can be suppressed by changing the distribution of the drive torque so as to suppress the pitch angle jerk.

Further, the determination method by the turning determination unit 24 is not limited to that described above. For example, the turning performance may be determined only from the estimated lateral acceleration Ay _E estimated from the vehicle speed V and the steering angle θs, or the turning performance may be determined only from the actual lateral acceleration Ay _D detected by the lateral acceleration sensor 14. May be. In the former case, the lateral acceleration sensor 14 can be omitted (the device configuration can be simplified), and in the latter case, it can be determined whether or not to change the distribution with a small number of operations (the control configuration can be simplified). .

Alternatively, the estimated lateral acceleration Ay _E may be used as a main determination element, and the actual lateral acceleration Ay _D may be used supplementarily. For example, even if it is determined from the estimated lateral acceleration Ay _E that the vehicle 1 is traveling straight, the actual lateral acceleration Ay _D is a large value that cannot be considered as an error due to the influence of disturbance. The vehicle 1 may be determined to be turning because it is highly possible that the vehicle is drifting. Also, the two lateral acceleration Ay _E, may be determined turning resistance from the average value of Ay _D, the absolute value of the two lateral acceleration Ay without taking _E, straight only when within a certain range Ay _D It may be determined that the vehicle is turning, and if it is out of range, it may be determined that the vehicle is turning. Further, as the simplest determination method by the turning determination unit 24, the turning of the vehicle 1 may be determined directly from the steering angle θs. Further, as in the above embodiment, it is not necessary to set the predetermined value in two stages in order to set the gain Ga. For example, by using a map in which only the second predetermined value Ay ₂ is set, the gain is set. Ga may be set to 0 or 1.

The determination method according to the driving regeneration determination section 25 is not limited to those described above, may determine whether the driving state or regeneration state by any one of the signs of the presence and the total required torque T _R of the accelerator operation. Alternatively, the accelerator pedal opening AP decreases from the state of the accelerator-on, it may be determined that the decrease rate (accelerator opening acceleration) changes to regenerated from the drive if the predetermined value or less, the total required torque T _R It may be determined that the rate of decrease in the change has been regenerated below a predetermined value. In the above embodiment, and if the sign is positive accelerator-off and total required torque T _R, if the sign is negative the accelerator ON and the total required torque T _R, change of the gain Gb is zero allocation is inhibited However, the gain Gb may be configured to output 1 or −1, for example, when it is determined whether the driving or regeneration is based only on the accelerator operation.

In the above embodiment, the drive torque distribution unit 23 calculates the temporary distribution change amount DT, and the torque command unit 26 multiplies the temporary distribution change amount DT by the gains Ga and Gb to obtain the final torque distribution change amount ΔT. However, the temporary distribution change amount DT may be used as it is as the drive torque distribution change amount when changing the distribution. That is, the gains Ga and Gb may be omitted. Drive torque control unit 22, in accordance with the differential value of the total required torque T _R as at least the target driving torque, as long as it changes the torque distribution.

  In the above embodiment, the drive torque distribution is changed in all the four travel states A to D shown in Table 1, but the drive torque distribution is not changed in all the four travel states A to D. May be. For example, the driving torque distribution may be changed in the driving states A and C where the differential value tends to be large, or the driving torque distribution is changed only when the motors 3f and 3r are driven (when the motors 3f and 3r are regenerated). The change of the distribution of the drive torque may be prohibited).

Further, a slip detection unit that detects the slip state of the vehicle 1 may be provided, and change of the drive torque distribution may be prohibited when the slip state is detected.
The vehicle 1 is not limited to that described above, and may be any vehicle provided with at least two drive sources capable of independently driving the front wheels 2f and the rear wheels 2r. For example, an in-wheel motor type electric vehicle in which motors are incorporated in all four wheels may be used, or an electric vehicle provided with two front motors 3f and one rear motor 3r. Further, it may be a hybrid vehicle in which one of the front wheel 2f and the rear wheel 2r is driven by an engine and the other is driven by a motor.

1 vehicle 2f front wheel 2r rear wheel 3f front motor (electric motor, drive source)
3r Rear motor (electric motor, drive source)
8f, 8r Suspension 10 Steering wheel 11 Accelerator pedal 12 Brake pedal 13 Vehicle speed sensor 14 Lateral acceleration sensor 15 Steering angle sensor 16 Accelerator opening sensor 17 Brake switch 20 ECU (control device)
21 Calculation unit 22 Drive torque control unit

Claims (7)

A vehicle control device comprising at least two drive sources for independently driving front wheels and rear wheels,
A calculation unit for calculating a target driving torque of the vehicle based on a driving operation of the driver;
A drive torque control unit that changes a distribution of the drive torque applied to the front wheels and the drive torque applied to the rear wheels according to the differential value of the target drive torque calculated by the calculation unit ;
The drive torque control unit prohibits the distribution change when the accelerator is off and the sign of the target drive torque of the vehicle is positive, and when the accelerator is on and the sign of the target drive torque of the vehicle is negative. A vehicle control device characterized by the above. The vehicle control device according to claim 1, wherein the driving operation of the driver is an accelerator pedal operation and / or a brake pedal operation . The drive torque control unit calculates the drive torque distribution change amount when changing the distribution as a value obtained by multiplying a differential value of the target drive torque calculated by the calculation unit by a predetermined coefficient. The vehicle control device according to claim 1 or 2 . A lateral acceleration sensor for detecting a lateral acceleration of the vehicle;
4. The vehicle control device according to claim 3 , wherein the drive torque control unit prohibits the change of the distribution when an actual lateral acceleration detected by the lateral acceleration sensor is equal to or greater than a predetermined value. A vehicle speed sensor for detecting the vehicle speed of the vehicle, and a steering angle sensor for detecting a steering angle of the steering wheel,
The drive torque control unit
An estimated lateral acceleration of the vehicle is calculated based on a vehicle speed detected by the vehicle speed sensor and a steering angle detected by the steering angle sensor, and an absolute value of the estimated lateral acceleration and an absolute value of the actual lateral acceleration are calculated. 5. The vehicle control device according to claim 4 , wherein a larger value is selected as the selected lateral acceleration, and the change of the distribution is prohibited when the selected lateral acceleration is equal to or greater than a predetermined value. The drive torque control unit
The vehicle control device according to claim 5 , wherein when the selected lateral acceleration is less than the predetermined value, the distribution change amount is gradually decreased according to an increase in the selected lateral acceleration. The drive torque control unit
If the selected lateral acceleration is less than a first predetermined value, set a dead zone to change the distribution by the distribution change amount,
If the selected lateral acceleration is greater than or equal to a second predetermined value, the change of the distribution is prohibited,
6. The vehicle according to claim 5 , wherein when the selected lateral acceleration is equal to or greater than the first predetermined value and less than the second predetermined value, the distribution is changed by an allocation change amount corresponding to the selected lateral acceleration. Control device.

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