JP6198036B2 - Vehicle control device - Google Patents

Description

  The present invention relates to a vehicle control device, and more particularly to a vehicle control device that prevents a vehicle from sliding down on a slope or the like in an electric vehicle such as a hybrid vehicle or an electric vehicle.

Conventionally, in a vehicle equipped with an automatic transmission (AT), due to its mechanism, a creep torque is generated that the vehicle travels without stepping on the accelerator pedal.
In addition, electric vehicles such as hybrid vehicles and electric vehicles adopt a structure in which creep torque is not generated by controlling motor torque.
However, even in an electric vehicle, in general, a setting that generates creep torque is not given to a driver who is accustomed to a vehicle equipped with an automatic transmission (AT) because the creep torque is not generated. Is often applied. However, generating a creep torque when the vehicle is depressed while the brake pedal is depressed consumes drive energy unnecessarily, which is not a preferable situation. In view of this situation, it has been proposed to control the creep torque according to the depression state of the brake pedal.
Further, in an electric vehicle, it is preferable from the viewpoint of fuel consumption that the creep torque is set to zero (0) while the vehicle is stopped. However, when the vehicle is stopped during climbing, the creep torque is reduced or zero ( In the case of 0), there was a concern that the vehicle would slide between the brake release and the generation of creep torque.
As such a vehicle control device, there are the following prior art documents.

JP 2004-320850 A JP 2011-230551 A JP2011-229348A

The motor torque control device for a vehicle according to Patent Document 1 is a configuration that avoids slipping down when starting a slope as a concern that occurs when the creep torque is reduced, and when the braking force is in a direction to increase. When the motor torque (creep torque) is promptly set to zero (0) and the braking force is in a decreasing direction, the motor torque (creep torque) is generated according to the depression amount of the brake pedal.
The vehicle start assist control system according to Patent Document 2 detects or estimates a certain road surface gradient, and sets a target vehicle speed at the start according to the gradient and the elapsed time from the start or the elapsed time from the accelerator operation. The drive device and the like are controlled so that the target vehicle speed is reached when starting.
The hill start assist control device and the control method thereof according to Patent Document 3 reduce the creep torque based on the road surface gradient of the uphill road and the brake force before being returned when the brake pedal is returned when the uphill road stops. The amount is calculated, and the creep torque is set based on the calculated reduction amount of the creep torque.

  By the way, according to the above cited document 1, when starting from a vehicle stop on a slope while suppressing power consumption, a creep torque can be generated according to a brake release to prevent a slip on the slope. Since it is not determined whether the vehicle is currently parked on a slope or not when determining whether to set it to zero (0), if the driver releases the brake pedal momentarily rather than gradually, creep will occur. There is a risk that the generation of torque will not be in time and the vehicle will slip down, and an improvement has been desired.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a vehicle control device that can prevent a vehicle from sliding down without wasting power.

The present invention relates to a vehicle control apparatus including a control unit that controls a torque amount of a creep torque generated by a drive motor that drives a vehicle, a vehicle speed detection unit that detects a vehicle speed, and a brake operation detection unit that detects a brake operation. When the accelerator opening detection means for detecting an accelerator opening, the vehicle and the road surface condition acquisition unit that calculates or obtains the inclination amount of the road surface that is stopped, the slope of the road surface which is calculated or acquired by the road surface condition acquisition unit Torque amount changing means for changing the amount of the creep torque according to the amount, the vehicle speed detected by the vehicle speed detecting means becomes a predetermined value or less, the brake operation detecting means detects the brake operation, and When the accelerator opening detected by the accelerator opening detecting means becomes a predetermined value or less, the creep torque is reduced. When the vehicle is stopped by the vehicle speed detected by the vehicle speed detecting means and the brake operation is detected by the brake operation detecting means, the amount of creep torque is obtained as the road surface state acquiring means. And the creep torque is not generated when the road slope calculated or acquired by the road condition acquisition means is equal to or less than a threshold value. And

  The present invention can prevent the vehicle from sliding down without consuming electric power wastefully.

FIG. 1 is a block diagram of a vehicle control device. (Example) FIG. 2 is a diagram showing a table in which a creep torque is set according to the amount of inclination (inclination angle). (Example) FIG. 3 is a flowchart of creep torque control when the vehicle is stopped. (Example) FIG. 4 is a time chart of control on a flat road. (Example) FIG. 5 is a time chart of control on a slope. (Example)

  The present invention achieves the object of preventing the vehicle from sliding down without consuming electric power wastefully by changing the amount of torque in accordance with the state of inclination of the road surface.

1 to 5 show an embodiment of the present invention.
As shown in FIG. 1, an electric vehicle (hereinafter referred to as “vehicle”) such as a hybrid vehicle or an electric vehicle includes a drive motor 1 for driving the vehicle, and a control device 2 for controlling the drive motor 1. Is installed.
The control device 2 includes control means 3 that controls the amount of creep torque generated by the drive motor 1.
The control means 3 includes a vehicle speed detection means 4 for detecting a vehicle speed (hereinafter referred to as “vehicle speed”), a brake operation detection means 5 for detecting a brake operation in a depressed state of the brake pedal by on / off, and an accelerator pedal. The accelerator opening detecting means 6 for detecting the accelerator opening that is in the depressed state is connected.
The control unit 3, as the road surface condition acquisition unit 7 the vehicle is also calculated inclination amount of the road surface it is stopped acquires acceleration (G) sensor 8 is connected.

The control means 3 is the amount of road surface inclination acquired by the road surface condition acquisition means 7 when the vehicle is stopped by the vehicle speed detected by the vehicle speed detection means 4 and the brake operation is detected by the brake operation detection means 5. Torque amount changing means 3A for changing the torque amount according to (inclination angle) is provided.
This torque changing means 3A is executed when the stop state of the vehicle continues for a certain time.
Therefore, a creep torque (Nm) corresponding to the amount of inclination (inclination angle (%)) is set in the control means 3 as shown in FIG. In FIG. 2, it is determined that creep torque is not required when the amount of inclination (inclination angle (%)) is equal to or less than the threshold value (2%).

  That is, in this embodiment, the acceleration (G) sensor 8 serving as the road surface condition acquisition means 7 recognizes the amount of road surface inclination (inclination angle) to detect a slope, and in detecting a slope, the creep torque is zero (0). Instead, the creep torque is left in accordance with the amount of inclination (inclination angle). On the other hand, in the detection of a flat road, the creep torque is set to zero (0), thereby reducing power consumption and vehicle shear. Both fall prevention is established. Further, in detecting a slope, even when the brake pedal is released momentarily, creep torque remains in advance to prevent the vehicle from falling down.

Next, creep torque control when the vehicle is stopped according to this embodiment will be described based on the flowchart of FIG.
As shown in FIG. 3, when the program of the control means 3 is started (step A01), first, it is determined whether or not the vehicle is in a stopped state, that is, the vehicle speed detected by the vehicle speed detection means 4 is vehicle speed ≦ a ( It is determined whether or not (a predetermined value) (step A02).
If this step A02 is YES, it is determined whether or not the brake pedal is depressed, that is, whether or not the brake operation detecting means 5 is on (step A03).
If this step A03 is YES, it is determined whether or not the accelerator pedal is depressed, that is, whether or not the accelerator opening detected by the accelerator opening detecting means 6 is accelerator opening ≦ b (predetermined value). (Step A04).
When this step A04 is YES, the counter increment for satisfying the creep torque control condition is started (step A05).
On the other hand, when step A02 is NO, when step A03 is NO, or when step A04 is NO, it is determined that this control is not being used, and the counter is reset (step A06).
After the process of step A05, it is determined whether or not the counter has passed a predetermined value (a fixed time) d (step A07).
When step A07 is YES, the creep torque control condition is satisfied (step A08), and the command torque is calculated according to the amount of inclination (inclination angle) (step A09).
In this step A09, the creep torque amount is set based on the table of FIG. 2, and when the inclination amount (inclination angle) is equal to or less than the threshold value (2%), it is determined that the creep torque is unnecessary, and is zero (0). To do. On the other hand, on slopes where the amount of tilt (tilt angle) is more than the threshold (2%), creep torque is generated to the extent that the vehicle does not slide down during brake release, thereby preventing the vehicle from falling down when the vehicle starts. it can.
On the other hand, when step A07 is NO or after the processing of step A06, the creep torque control condition is not established (step A10), and the command torque is calculated by the normal control (step A11).
After the process of step A09 or after the process of step A11, this program is returned (step A12).

4 and 5 show time charts of control when the flat road is stopped and when the hill is stopped.
FIG. 4 shows a case of stopping on a flat road. FIG. 5 shows a case of stopping on a hill. In a case of stopping on a flat road, as shown in FIG. 4, at a point A, the vehicle speed is a predetermined value a or less, the brake operation detecting means 5 is turned on, The opening degree becomes equal to or less than the predetermined value b, and the counter is incremented to establish the creep torque control.
Then, at the point B, when the counter becomes a predetermined value (a certain time) d or more and the creep torque control condition is satisfied, the creep torque set in the table of FIG. 2 is shifted according to the amount of inclination (inclination angle). . At this time, since the creep torque becomes zero (0), wasteful power consumption can be prevented.
On the other hand, when the vehicle is stopped on a slope, as shown in FIG. 5, if the creep torque is set to zero (0), the vehicle will slip down at the next start. By generating the vehicle, it is possible to prevent the vehicle from sliding down.

As a result, in this embodiment, when the vehicle is stopped by the vehicle speed detected by the vehicle speed detecting means 4 and the brake operation is detected by the brake operation detecting means 5, the control means 3 is the road surface condition acquiring means. Torque amount changing means 3 </ b> A for changing the amount of torque according to the amount of road surface inclination obtained by 7.
With such a configuration, only a torque amount that can maintain the stop state of the vehicle is generated, so that power is not wasted. Thereby, it is possible to reduce the electric power generation amount (or charge amount) required only for creep torque.
The road surface condition acquisition means 7 is an acceleration sensor 8. The torque amount changing means 3A is executed when the stop state of the vehicle continues for a certain time.
With such a configuration, even when the acceleration sensor 8 is used to acquire the road surface state, it is possible to realize highly accurate torque amount change control.

  The vehicle control device according to the present invention can be applied to various vehicles.

DESCRIPTION OF SYMBOLS 1 Drive motor 2 Control apparatus 3 Control means 3A Torque amount change means 4 Vehicle speed detection means 5 Brake operation detection means 6 Accelerator opening degree detection means 7 Road surface condition acquisition means 8 Acceleration (G) sensor

Claims (2)

In a vehicle control device comprising control means for controlling the amount of creep torque generated by a drive motor that drives a vehicle,
Vehicle speed detecting means for detecting the vehicle speed;
Brake operation detecting means for detecting the brake operation;
An accelerator opening detecting means for detecting the accelerator opening;
Road surface condition acquisition means for calculating or acquiring the amount of inclination of the road surface on which the vehicle is stopped;
Torque amount changing means for changing the torque amount of the creep torque according to the road surface inclination amount calculated or acquired by the road surface state acquiring means,
When the vehicle speed detected by the vehicle speed detecting means is less than a predetermined value, the brake operation is detected by the brake operation detecting means, and the accelerator opening detected by the accelerator opening detecting means is less than a predetermined value. And generating the creep torque,
When the vehicle is stopped by the vehicle speed detected by the vehicle speed detection means and the brake operation is detected by the brake operation detection means, the torque amount of the creep torque is calculated by the road surface condition acquisition means or While changing according to the acquired slope amount of the road surface,
The vehicle control apparatus according to claim 1, wherein the creep torque is not generated when a road surface inclination amount calculated or acquired by the road surface state acquisition unit is equal to or less than a threshold value. The road surface state acquisition means is an acceleration sensor,
The vehicle control device according to claim 1, wherein the torque amount changing unit is executed when a stop state of the vehicle continues for a predetermined time.

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