JP7385464B2 - Vehicle control device - Google Patents

Description

The present invention relates to a vehicle control device that controls a driving motor connected to drive wheels.

BACKGROUND ART Vehicles such as electric vehicles and hybrid vehicles are provided with a driving motor connected to drive wheels (see Patent Documents 1 to 3). Further, the target driving force of the travel motor is controlled based on the accelerator operation by the occupant.

Japanese Patent Application Publication No. 2012-157214 JP2013-59223A

Incidentally, the driving motor connected to the driving wheels generally has a driving force characteristic in which the motor driving force decreases as the vehicle speed, that is, the motor rotation speed increases. As a result, even if the accelerator is operated in the same way in both high and low vehicle speed regions, it is more difficult to obtain a sense of acceleration in the high vehicle speed region where the motor drive force decreases than in the low vehicle speed region. there were. Therefore, it is required to control the driving motor so as to give the driver a sense of acceleration.

An object of the present invention is to control a driving motor so as to give a driver a feeling of acceleration.

A vehicle control device according to an embodiment of the present invention is a vehicle control device that controls a driving motor connected to a drive wheel, and includes a first target driving force that sets a first target driving force based on an accelerator opening degree. a second driving force setting section that sets a second target driving force larger than the first target driving force based on the first target driving force; and a motor control section that controls the motor driving force output from the traveling motor . The motor control unit increases the motor driving force toward the second target driving force and then increases the motor driving force toward the first target driving force when the vehicle speed exceeds the speed threshold and the accelerator operation speed exceeds the threshold. and lowers the motor driving force, and increases the motor driving force toward the first target driving force during accelerated driving when the accelerator operation speed is less than the threshold value.
A vehicle control device according to another embodiment of the present invention is a vehicle control device that controls a driving motor connected to a drive wheel, and includes a first target driving force that sets a first target driving force based on an accelerator opening degree. a second driving force setting section that sets a second target driving force larger than the first target driving force based on the first target driving force; and a motor control section that controls the motor driving force output from the traveling motor. The motor control section increases the motor driving force toward the second target driving force during acceleration driving when the accelerator operation speed exceeds a threshold value, and then decreases the motor driving force toward the first target driving force and accelerates the accelerator. The motor driving force is increased toward the first target driving force during accelerated driving when the operation speed is less than the threshold value. The second driving force setting section increases the difference between the first target driving force and the second target driving force as the vehicle speed increases.

According to the present invention, the motor control section increases the motor driving force toward the second target driving force and then increases the motor driving force toward the first target driving force during acceleration traveling in which the accelerator operation speed exceeds the threshold value. Lower it. Thereby, the driving motor can be controlled so as to give the driver a sense of acceleration.

1 is a schematic diagram showing a configuration example of a vehicle equipped with a vehicle control device according to an embodiment of the present invention. FIG. 3 is a diagram showing an example of a driving force map in which a first target driving force is set. 3 is a flowchart illustrating an example of an execution procedure of vehicle acceleration control. 5 is a timing chart showing an example of an execution status of vehicle acceleration control. 5 is a timing chart showing an example of an execution status of vehicle acceleration control. (A) to (C) are diagrams showing examples of setting increase coefficients.

Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

[Vehicle configuration]
FIG. 1 is a schematic diagram showing an example of the configuration of a vehicle 11 including a vehicle control device 10 according to an embodiment of the present invention. As shown in FIG. 1, the vehicle 11 is provided with a motor generator (driving motor) 13 connected to rear wheels (drive wheels) 12. A rear wheel 12 is connected to a rotor 13r of this motor generator 13 via a motor output shaft 14, a differential mechanism 15, and a wheel drive shaft 16. Further, an inverter 17, which is a power conversion device, is connected to the stator 13s of the motor generator 13, and a battery 18, such as a lithium ion battery, is connected to the inverter 17. Although the illustrated vehicle 11 is a rear-wheel drive vehicle, it is not limited to this, and may be a front-wheel drive vehicle that drives the front wheels 19, or an all-wheel drive vehicle that drives the front and rear wheels 12, 19. It may be a vehicle.

The vehicle control device 10 includes a main controller 21 and a motor controller 22 including a microcomputer or the like in order to control the motor driving force output from the motor generator 13. A first driving force setting unit 23 provided in the main controller 21 sets a first target driving force Tf1 based on the accelerator opening degree and the like, and outputs this first target driving force Tf1 to the motor controller 22. Further, the motor controller 22 functioning as a motor control section controls the motor driving force of the motor generator 13 based on the first target driving force Tf1. Sensors connected to the main controller 21 include an accelerator sensor 25 that detects the amount of depression of the accelerator pedal 24 (hereinafter referred to as accelerator opening), a brake sensor 27 that detects the amount of depression of the brake pedal 26, and a vehicle speed. There is a vehicle speed sensor 28 etc. that Note that the main controller 21 and the motor controller 22 are communicably connected to each other via an in-vehicle network 29 such as CAN.

[Setting target driving force]
Next, the setting of the first target driving force Tf1 by the main controller 21 will be explained. FIG. 2 is a diagram showing an example of a driving force map in which the first target driving force Tf1 is set. As shown in FIG. 2, the driving force map has characteristic lines L1 to L4 indicating the first target driving force Tf1 for each accelerator opening Acc. That is, when the accelerator opening Acc is 0%, the first target driving force Tf1 is set along the characteristic line L1, and when the accelerator opening Acc is 25%, the first target driving force Tf1 is set along the characteristic line L2. A first target driving force Tf1 is set. Similarly, when the accelerator opening Acc is 50%, the first target driving force Tf1 is set along the characteristic line L3, and when the accelerator opening Acc is 100%, the first target driving force Tf1 is set along the characteristic line L4. The first target driving force Tf1 is set. For example, when the accelerator opening degree Acc is "50%" and the vehicle speed is "Vx", "Fx" is set as the first target driving force Tf1 requested by the driver. In addition, although four characteristic lines L1 to L4 are set as an example in the driving force map shown in FIG. You can also use a map.

By the way, as shown in FIG. 2, the driving force characteristic of the motor generator 13 is such that in a vehicle speed range exceeding a predetermined vehicle speed, the motor driving force decreases as the vehicle speed, that is, the motor rotation speed increases. For this reason, it has been more difficult to give the driver a sense of acceleration in a high vehicle speed region than in a low vehicle speed region. That is, when the accelerator pedal 24 is depressed in a low vehicle speed region and the accelerator opening degree Acc increases from 0% to 50%, the first target driving force Tf1 increases as shown by the arrow α. On the other hand, when the accelerator pedal 24 is similarly depressed in the high vehicle speed region and the accelerator opening degree Acc increases from 0% to 50%, the first target driving force Tf1 increases as shown by the arrow β. That is, in a low vehicle speed region, the vehicle 11 is accelerated with a driving force Fa that exceeds the running resistance, whereas in a high vehicle speed region, the vehicle 11 is accelerated with a driving force Fb that is significantly smaller than the driving force Fa. Become. In this way, even if the driver performs the same accelerator operation, it is more difficult to give the driver a sense of acceleration in a high vehicle speed region than in a low vehicle speed region.

Therefore, the vehicle control device 10 of the present embodiment is based on vehicle acceleration control, which will be described later, in order to give the driver a feeling of acceleration even in a high vehicle speed region during acceleration driving when the driver depresses the accelerator pedal 24. Controls motor driving force. For this reason, the main controller 21 of the vehicle control device 10 is provided with a second driving force setting section 30 and an operation speed calculation section 31. As will be described later, the second driving force setting unit 30 of the main controller 21 sets a second target driving force larger than the first target driving force Tf1 by multiplying the first target driving force Tf1 by a predetermined increase coefficient k. Set force Tf2. Further, the operating speed calculation unit 31 of the main controller 21 calculates the operating speed when the accelerator pedal 24 is depressed based on the accelerator opening degree transmitted from the accelerator sensor 25.

[Vehicle acceleration control]
Vehicle acceleration control for giving the driver a sense of acceleration will be described below. FIG. 3 is a flowchart showing an example of an execution procedure of vehicle acceleration control. Further, FIGS. 4 and 5 are timing charts showing an example of the execution status of vehicle acceleration control. The timing chart in FIG. 4 shows the execution situation when the accelerator operation speed AS is high, and the timing chart in FIG. 5 shows the execution situation when the accelerator operation speed AS is slow.

As shown in FIG. 3, in step S10, it is determined whether the accelerator pedal 24 has been depressed by the driver, that is, whether the accelerator opening has changed to the depression side by exceeding a predetermined amount. If it is determined in step S10 that the accelerator pedal 24 has been depressed, the process advances to step S11 to determine whether the vehicle speed V exceeds a predetermined speed threshold V1, that is, whether the vehicle is traveling in a high vehicle speed region. is determined. If it is determined in step S11 that the vehicle speed V exceeds the speed threshold value V1, the process proceeds to step S12, where the operation speed of the accelerator pedal 24 (hereinafter referred to as accelerator operation speed AS) exceeds the predetermined threshold value S1. It is determined whether or not.

In step S12, if it is determined that the accelerator operation speed AS exceeds the threshold value S1, the process proceeds to step S13, and by referring to the driving force map in FIG. Driving force Tf1 is set. In the subsequent step S14, the first target driving force Tf1 is multiplied by a predetermined increase coefficient k, and a second target driving force Tf2, which is larger than the first target driving force Tf1, is set. When the first and second target driving forces Tf1 and Tf2 are set, the process advances to step S15, where the motor driving force MF is increased toward the second target driving force Tf2, and then, the process advances to step S16, where the first target Motor driving force MF is lowered toward driving force Tf1. By controlling the motor driving force MF in this manner, it is possible to give the driver a sense of acceleration.

That is, as shown in FIG. 4, when the accelerator pedal 24 is quickly depressed (symbol a1) and the accelerator operation speed AS exceeds the threshold value S1 (symbol b1), the first target driving force Tf1 is set based on the accelerator opening degree Acc. At the same time, a second target driving force Tf2 larger than the first target driving force Tf1 is set. Then, the motor driving force MF of the motor generator 13 is increased toward the second target driving force Tf2 (symbol c1), and then lowered toward the first target driving force Tf1 (symbol c2). In this way, by actively overshooting the motor driving force MF from the first target driving force Tf1, the jerk acting on the vehicle 11 can be changed from the positive side to the negative side (symbols d1, d2). In this way, by changing the jerk of the vehicle 11 from the positive side to the negative side, it is possible to positively give the driver a feeling of change in motion, and it is possible to give the driver a feeling of acceleration when the accelerator pedal 24 is depressed. can. Note that jerk (jerk, jerk) is a physical quantity indicating a change in motion, and is a time differential value of acceleration.

Further, as shown in the flowchart of FIG. 3, if it is determined in step S12 that the accelerator operation speed AS is less than or equal to the threshold value S1, the process proceeds to step S17, and the first target is set based on the accelerator opening degree Acc and the vehicle speed V. The driving force Tf1 is set, and the process proceeds to step S18, where the motor driving force MF is increased toward the first target driving force Tf1. In other words, if it is determined that the accelerator pedal 24 is being depressed gently and the acceleration request from the driver is low, the direction toward the first target driving force Tf1 is determined without using the second target driving force Tf2 described above. As a result, the motor driving force MF is increased. By controlling the motor driving force MF in this manner, the vehicle 11 can be gently accelerated without giving the driver a sense of discomfort.

That is, as shown in FIG. 5, when the accelerator pedal 24 is gently depressed (symbol e1) and the accelerator operation speed AS falls below the threshold value S1 (symbol f1), the first target driving force Tf1 is applied based on the accelerator opening degree Acc. is set. Then, the motor driving force MF of the motor generator 13 is increased toward the first target driving force Tf1 (symbol g1). In this way, when the accelerator pedal 24 is depressed gently, the change in jerk acting on the vehicle 11 can be suppressed by gradually increasing the motor driving force MF (symbol h1). By gradually changing the jerk of the vehicle 11 in this way, the vehicle 11 can be gently accelerated without giving the driver a sense of discomfort.

Furthermore, as shown in the flowchart of FIG. 3, even if it is determined in step S11 that the vehicle speed V is equal to or less than the speed threshold value V1, the process proceeds to step S17, and the first target drive is performed based on the accelerator opening degree Acc and the vehicle speed V. The force Tf1 is set, and the process proceeds to step S18, where the motor driving force MF is increased toward the first target driving force Tf1. In other words, if it is determined that the vehicle speed V is less than or equal to the speed threshold V1, and therefore the vehicle is traveling in a low speed region where a feeling of acceleration can be easily obtained, the second target driving force Tf2 described above is not used. The motor driving force MF is increased toward the target driving force Tf1.

As described above, when the driver depresses the accelerator pedal 24, the control method for increasing the motor driving force MF is changed based on the accelerator operation speed AS at the time of depressing the accelerator pedal 24. That is, during acceleration driving when the accelerator pedal 24 is quickly depressed, that is, during acceleration driving when the accelerator operation speed AS exceeds the threshold value S1, the motor driving force MF is increased to the second target driving force Tf2, and then the motor driving force MF is increased to the second target driving force Tf2. 1 target driving force Tf1. In this way, by actively overshooting the motor driving force MF from the first target driving force Tf1, it is possible to give the driver a great sense of acceleration. On the other hand, during acceleration driving when the accelerator pedal 24 is gently depressed, that is, during acceleration driving when the accelerator operation speed AS is lower than the threshold value S1, the motor driving force MF is set to the first target driving force without using the second target driving force Tf2 described above. The force can be raised to Tf1. In this way, by controlling the motor driving force MF without overshooting, it is possible to gently accelerate the vehicle 11 without giving the driver a sense of discomfort.

[Other embodiments]
As described above, by multiplying the first target driving force Tf1 by the increase coefficient k, the second target driving force Tf2, which is larger than the first target driving force Tf1, is set. In this way, as the increase coefficient k by which the first target driving force Tf1 is multiplied, a preset fixed value may be used, or a value that changes depending on the accelerator operation speed AS or the like may be used. Here, FIGS. 6A to 6C are diagrams showing examples of setting the increase coefficient k.

As shown in FIG. 6(A), the increase coefficient k is set larger as the accelerator operation speed AS becomes higher. In this way, by changing the increase coefficient k according to the accelerator operation speed AS, it is possible to increase the difference between the first target driving force Tf1 and the second target driving force Tf2 as the accelerator operation speed AS increases. can. As a result, the more quickly the driver depresses the accelerator pedal 24 with the intention of strong acceleration, the greater the motor drive force MF can be overshot, and the jerk of the vehicle 11 can be greatly changed, resulting in stronger acceleration for the driver. It can give a feeling.

As shown in FIG. 6(B), the increase coefficient k is set larger as the accelerator opening degree Acc becomes larger. In this way, by changing the increase coefficient k according to the accelerator opening Acc, it is possible to increase the difference between the first target driving force Tf1 and the second target driving force Tf2 as the accelerator opening Acc increases. can. As a result, the more the driver depresses the accelerator pedal 24 with the intention of strong acceleration, the more the motor driving force MF can be greatly overshot, and the jerk of the vehicle 11 can be greatly changed. It can give a feeling of acceleration.

As shown in FIG. 6(C), the increase coefficient k is set to be larger as the vehicle speed V becomes higher. In this way, by changing the increase coefficient k according to the vehicle speed V, it is possible to increase the difference between the first target driving force Tf1 and the second target driving force Tf2 as the vehicle speed V increases. As a result, the motor driving force MF can be greatly overshot to the extent that the motor driving force MF that can be output decreases as the vehicle speed V increases, and the jerk of the vehicle 11 can be greatly changed. It can give a strong sense of acceleration.

In addition, in the examples shown in FIGS. 6A to 6C, the increase coefficient k is changed based only on the accelerator operation speed AS, the increase coefficient k is changed based only on the accelerator opening degree Acc, and the increase coefficient k is changed based only on the vehicle speed V. Although the increase coefficient k is changed, it is not limited to this. For example, the increase coefficient k may be changed based on the accelerator operation speed AS, the accelerator opening degree Acc, and the vehicle speed V. Also in this case, the increase coefficient k becomes larger as the accelerator operation speed AS becomes higher, the increase coefficient k becomes larger as the accelerator opening degree Acc becomes larger, and the increase coefficient k becomes larger as the vehicle speed V becomes higher. Further, the increase coefficient k may be changed based on both the accelerator operation speed AS and the accelerator opening degree Acc, or the increase coefficient k may be changed based on both the accelerator operation speed AS and the vehicle speed V. The increase coefficient k may be changed based on both the degree Acc and the vehicle speed V.

Furthermore, in the above description, the second target driving force Tf2, which is larger than the first target driving force Tf1, is set by multiplying the first target driving force Tf1 by the increase coefficient k, but the present invention is not limited to this. Instead, the second target driving force Tf2 may be set using another method. For example, the second target driving force Tf2, which is larger than the first target driving force Tf1, may be set by adding a predetermined driving force to the first target driving force Tf1. Further, as the driving force to be added to the first target driving force Tf1, a preset fixed value may be used, and as shown in FIGS. It is also possible to use a value that changes depending on the

It goes without saying that the present invention is not limited to the embodiments described above, and can be modified in various ways without departing from the spirit thereof. In the above description, the vehicle 11 to which the vehicle control device 10 is applied is exemplified as an electric vehicle having only a running motor as a power source; however, the present invention is not limited to this; It may also be a hybrid vehicle equipped with a motor and an engine. Further, in the above description, the main controller 21 is made to function as the first driving force setting section 23 and the second driving force setting section 30, and the motor controller 22 is made to function as a motor control section, but the invention is not limited to this. do not have. For example, one controller may function as the first driving force setting section, the second driving force setting section, and the motor control section.

In the above description, the motor driving force MF is controlled based on the first and second target driving forces Tf1 and Tf2 in the speed region where the vehicle speed V exceeds the speed threshold value V1, but the invention is not limited to this. The motor driving force MF may be controlled based on the first and second target driving forces Tf1 and Tf2 in all speed ranges including the low vehicle speed range. Thereby, even in a low vehicle speed region, the motor driving force MF can be actively overshot, and a stronger sense of acceleration can be given to the driver.

In the above description, the motor driving force MF is controlled based on the first and second target driving forces Tf1 and Tf2 in a speed range where the vehicle speed V exceeds the speed threshold value V1, regardless of the magnitude of the accelerator opening degree Acc. However, it is not limited to this. For example, only when the accelerator opening degree Acc exceeds a predetermined opening threshold value, that is, when the driver depresses the accelerator pedal 24 greatly with the intention of strong acceleration, based on the first and second target driving forces Tf1 and Tf2. The motor driving force MF may also be controlled.

10 Vehicle control device 11 Vehicle 12 Rear wheel (drive wheel)
13 Motor generator (travel motor)
21 Main controller 22 Motor controller (motor control section)
23 First driving force setting section 30 Second driving force setting section Acc Accelerator opening degree AS Accelerator operation speed S1 Threshold Tf1 First target driving force Tf2 Second target driving force MF Motor driving force V Vehicle speed V1 Speed threshold

Claims (5)

A vehicle control device that controls a travel motor connected to a drive wheel,
a first driving force setting section that sets a first target driving force based on the accelerator opening;
a second driving force setting unit that sets a second target driving force larger than the first target driving force based on the first target driving force;
a motor control unit that controls a motor driving force output from the traveling motor based on the first target driving force;
has
The motor control section includes:
During acceleration driving when the vehicle speed exceeds a speed threshold and the accelerator operation speed exceeds the threshold, the motor driving force is increased toward the second target driving force, and then the motor driving force is decreased toward the first target driving force. ,
increasing motor driving force toward the first target driving force during acceleration driving when the accelerator operation speed is less than the threshold value;
Vehicle control device. A vehicle control device that controls a travel motor connected to a drive wheel,
a first driving force setting section that sets a first target driving force based on the accelerator opening;
a second driving force setting unit that sets a second target driving force larger than the first target driving force based on the first target driving force;
a motor control unit that controls a motor driving force output from the traveling motor based on the first target driving force;
has
The motor control section includes:
During acceleration driving when the accelerator operation speed exceeds a threshold, increasing the motor driving force toward the second target driving force, and then lowering the motor driving force toward the first target driving force,
When accelerating when the accelerator operation speed is below the threshold, increasing the motor driving force toward the first target driving force;
The second driving force setting section includes:
increasing the difference between the first target driving force and the second target driving force as the vehicle speed increases;
Vehicle control device. The vehicle control device according to claim 2 ,
The motor control unit increases the motor driving force to the first target driving force after increasing the motor driving force toward the second target driving force during acceleration driving when the vehicle speed exceeds the speed threshold and the accelerator operation speed exceeds the threshold. Reduce the motor drive force towards
Vehicle control device. The vehicle control device according to any one of claims 1 to 3 ,
The second driving force setting section increases the difference between the first target driving force and the second target driving force as the accelerator operation speed increases.
Vehicle control device. The vehicle control device according to any one of claims 1 to 4 ,
The second driving force setting unit increases the difference between the first target driving force and the second target driving force as the accelerator opening increases.
Vehicle control device.

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