JP2021115866A - vehicle - Google Patents

Abstract

To provide a vehicle about which good operability is acquired when traveling by maintaining present speed.SOLUTION: A vehicle comprises: a mode control unit which is capable of switching to a first travel mode in which torque changes by following a drive operation and a second travel mode which performs travel which is closer to inertia travel than the first travel mode; a target torque calculation unit which calculates target torque on the basis of the drive operation; a first indication torque calculation unit which calculates indication torque which follows the target torque by adding a first variation limit in the first travel mode; a second indication torque calculation unit which calculates the indication torque which follows the target torque by adding a second variation limit against which limit is stronger than the first variation limit after the indication torque approaches zero in the second travel mode; and a drive control unit which drives a power source or a brake unit so that the calculated indication torque is outputted to a drive wheel.SELECTED DRAWING: Figure 3

Description

The present invention relates to a vehicle having a traveling mode close to coasting.

Patent Document 1 discloses a vehicle having an inertial traveling mode in which the clutch device is disengaged to perform inertial traveling. In the inertial running mode, the fuel consumption can be improved by reducing the running loss. The vehicle of Patent Document 1 shifts to the inertial driving mode when a predetermined driving condition is satisfied, and the inertial driving mode is released when the brake operation is performed above the threshold value or when the accelerator operation is performed above the threshold value. NS.

Japanese Unexamined Patent Publication No. 2016-22772

In the inertial driving mode, there is an advantage that the vehicle can maintain the current speed without delicate accelerator operation or delicate braking operation. However, it was foreseen that even during the coasting mode, the driver would be required to decelerate or accelerate slightly.

An object of the present invention is to provide a vehicle that can obtain good driving operability when traveling while maintaining the current speed.

The invention according to claim 1
A mode control unit that can switch between a first running mode in which the torque changes according to the driving operation and a second running mode in which the running is closer to coasting than the first running mode.
A target torque calculation unit that calculates the target torque based on the driving operation,
A first instruction torque calculation unit that calculates an instruction torque that follows the target torque by applying a first change amount limit in the first travel mode.
A second indicated torque calculation unit that calculates an indicated torque that follows the target torque by applying a second change amount limit that is stronger than the first change amount limit after the indicated torque is brought close to zero in the second traveling mode. When,
A drive control unit that drives the power source or braking unit so that the calculated indicated torque is output to the drive wheels.
It is a vehicle characterized by being provided with.

The invention according to claim 2 is the vehicle according to claim 1.
Equipped with a first operation unit for switching driving modes that can be operated by the driver
The mode control unit is characterized in that the mode control unit switches from the first travel mode to the second travel mode based on the operation of the first operation unit.

The invention according to claim 3 is the vehicle according to claim 1 or 2.
The mode control unit is characterized by switching from the second travel mode to the first travel mode when the difference between the instruction torque calculated by the second instruction torque calculation unit and the target torque becomes equal to or less than a threshold value. And.

The invention according to claim 4 is the vehicle according to any one of claims 1 to 3.
When switching from the first traveling mode to the second traveling mode, the target torque calculation unit shifts the target torque corresponding to the zero accelerator operating amount toward a negative and larger absolute value. It is characterized by having a relationship between the operating amount and the target torque.

The invention according to claim 5 is the vehicle according to any one of claims 1 to 3.
When switching from the first traveling mode to the second traveling mode, the target torque calculation unit shifts the target torque corresponding to the zero accelerator operating amount to the direction in which the absolute value becomes larger in the negative direction. It is possible to switch between the case of changing the relationship between the operation amount and the target torque and the case of not changing the relationship between the accelerator operation amount and the target torque under predetermined conditions.
The feature is that the value of the second change amount limit when the relationship is changed is set to a value having a stronger limit than the value of the second change amount limit when the relationship is not changed. do.

The invention according to claim 6 is the vehicle according to any one of claims 1 to 5.
Equipped with an engine that generates power for driving
The drive control unit can activate idling stop control for stopping the engine when the engine is idling.
The drive control unit is characterized in that the idling stop control is activated based on the switching of the traveling mode to the second traveling mode.

The invention according to claim 7 is the vehicle according to any one of claims 1 to 6.
Equipped with a second operation unit that can be operated by the driver
When the second operation unit is operated during the second travel mode, the second instruction torque calculation unit is characterized in that the absolute value of the instruction torque is reduced again.

According to the present invention, when the mode is switched to the second traveling mode, the indicated torque is brought close to zero, so that it is possible to shift to traveling in which the current speed is substantially maintained. Further, the second indicated torque calculation unit calculates an indicated torque that follows the target torque by applying a second change amount limit that is more restrictive than the first change amount limit. Therefore, when the driver receives a slight deceleration request or a slight acceleration request during driving in the second driving mode, a relatively large accelerator operation or braking operation is performed to decelerate or accelerate according to the request. realizable. That is, since a delicate driving operation is not required, good driving operability is realized.

It is a block diagram which shows the vehicle of Embodiment 1 of this invention. In the figure which shows the relationship between the accelerator operation amount and the target torque, (A) is the relationship in the normal operation mode, and (B) is the relationship in the one-pedal operation mode. It is a timing chart which shows the operation example when the inertia running mode is used at the time of signal stop. It is a flowchart which shows the procedure of the traveling mode switching process which the mode control unit of Embodiment 2 executes. It is a timing chart which shows the operation example when the inertia running mode of Embodiment 2 is used at the time of signal stop. It is a flowchart which shows the initial setting process at the time of the inertia traveling mode switching executed by the instruction torque calculation unit of Embodiment 3. It is a flowchart which shows the process at the time of traveling mode switching executed by the drive control unit of Embodiment 4. It is a flowchart of the button operation input process executed by the mode control unit and the instruction torque calculation unit of Embodiment 5.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment 1)
FIG. 1 is a block diagram showing a vehicle according to the first embodiment of the present invention. The vehicle 1 of the first embodiment is a HEV (Hybrid Electric Vehicle), and is a drive wheel 2, a traveling motor (power source) 3 that outputs driving power to the driving wheel 2, and an inverter 4 that drives the traveling motor 3. It has a battery 5 that supplies electric power for traveling to the inverter 4, an engine (internal combustion engine: power source) 6 that outputs electric power for traveling to drive wheels 2, and an auxiliary machine 7 that drives the engine 6. The inverter 4 can output acceleration torque to the drive wheels 2 by powering the traveling motor 3, and can output deceleration torque to the drive wheels 2 by regeneratively operating the traveling motor 3. Further, the vehicle 1 includes a driving operation unit 10 including a brake pedal 11, an accelerator pedal 12, and a steering handle 13 operated by the driver, an inertial traveling mode button 14 that can be operated by the driver, and a one-pedal mode for the driver. It is provided with a one-pedal display unit 15 for displaying that the vehicle is in the inertial traveling mode, a traveling mode display unit 16 for displaying to the driver that the vehicle is in the inertial traveling mode, and a control unit 20 for controlling each unit. The inertial traveling mode button 14 corresponds to an example of the first operation unit and the second operation unit according to the present invention.

The operation signals of the driving operation unit 10 and the inertial traveling mode button 14 are input to the control unit 20. The control unit 20 controls the vehicle 1 in response to the operation signals of the driving operation unit 10 and the inertial traveling mode button 14. For example, the control unit 20 can drive the inverter 4 or the auxiliary machine 7 to generate power in the traveling motor 3 or the engine 6 and output the acceleration torque to the drive wheels 2. Further, the control unit 20 can output a deceleration torque (braking force) to the drive wheels 2 by regeneratively operating the traveling motor 3. The control unit 20 may adopt a configuration in which a braking mechanism (not shown) is driven to output a deceleration torque (braking force) to the drive wheels 2. Further, the control unit 20 can output a display signal to the one-pedal display unit 15 and the traveling mode display unit 16 to switch between these displays. The traveling motor 3 or the braking mechanism that is regeneratively operated corresponds to an example of the braking unit according to the present invention.

The control unit 20 may be composed of one ECU (Electronic Control Unit), or may be configured such that a plurality of ECUs operate in cooperation with each other. The ECU includes a ROM (Read Only Memory) that stores a control program and a CPU (Central Processing Unit) that performs calculation processing. When the CPU executes the control program, a plurality of functional modules are used in the control unit 20. Is realized. The plurality of functional modules include a mode control unit 21 that switches the driving mode, a target torque calculation unit 22 that calculates a target torque based on the operation signal of the operation operation unit 10 and a system request, and an instruction torque based on the target torque. The instruction torque calculation unit 23 to be calculated includes a drive control unit 24 that drives the traveling motor 3, the engine 6, or the braking mechanism so that the instruction torque is output from the drive wheels 2. The indicated torque calculation unit 23 in the normal traveling mode corresponds to an example of the first indicated torque calculating unit according to the present invention, and the indicated torque calculating unit 23 in the inertial traveling mode is the second indicated torque calculating unit according to the present invention. Corresponds to one example.

The target torque calculation unit 22 calculates the target torque corresponding to the operation amount of the accelerator pedal 12 and the brake pedal 11 based on the target torque data table 22a. The operation amount of the accelerator pedal 12 corresponds to an example of the accelerator operation amount according to the present invention. The target torque data table 22a stores data in the normal operation mode and data in the one-pedal operation mode. FIG. 2A shows the relationship between the accelerator pedal operation amount and the target torque in the normal operation mode, and FIG. 2B shows the relationship between the accelerator pedal operation amount and the target torque in the one-pedal operation mode. It is a figure. As shown in FIG. 2A, the target torque calculated by the target torque calculation unit 22 in the normal operation mode increases according to the operation amount of the accelerator pedal 12, and is the target when the operation amount of the accelerator pedal 12 is zero. The torque is near zero. Although not shown, the target torque in the normal operation mode is negative and the absolute value increases as the operation amount of the brake pedal 11 increases. As shown in FIG. 2B, the target torque in the one-pedal operation mode increases as the operation amount of the accelerator pedal 12 is larger than the first operation amount A1, and becomes negative and the absolute value becomes larger as the operation amount of the accelerator pedal 12 is smaller than the first operation amount A1. Become. Negative torque corresponds to deceleration torque.

The traveling mode that can be switched in the vehicle 1 includes a normal traveling mode and an inertial traveling mode. The normal traveling mode corresponds to an example of the first traveling mode according to the present invention. The inertial running mode corresponds to an example of the second running mode according to the present invention.

The normal traveling mode is a traveling mode in which the acceleration torque or the deceleration torque of the drive wheels 2 is obtained according to each operation amount of the brake pedal 11 or the accelerator pedal 12. The indicated torque calculation unit 23 calculates the indicated torque that follows the target torque by applying the first change amount limit in the normal traveling mode. The first change amount limit may be realized by a tilt limit that suppresses the time change amount of the indicated torque to a predetermined value or less, or a first-order lag filter having a predetermined time constant is used and the target torque is passed through the first-order lag filter. It may be realized by obtaining the indicated torque. The first change amount limit is set to the strength at which the indicated torque quickly follows the target torque in normal operation. For example, when the tilt limit is applied as the first change amount limit, a time change rate of about 40% of the maximum torque in 1 second may be adopted as the tilt limit value. Further, when a first-order lag filter is applied as the first change amount limit, a time constant of about 60% in 1 second may be adopted. Due to the first change amount limitation, even if there is a sudden change in the operating amount of the accelerator pedal 12, the indicated torque changes within the first change amount limitation, and the indicated torque, that is, the torque output to the drive wheel 2 is suddenly changed. Change is suppressed.

The inertial running mode is a running mode that can realize running closer to inertial running than the normal running mode. When the indicated torque calculation unit 23 switches to the inertial traveling mode, the indicated torque first brings the indicated torque close to zero. Specifically, the indicated torque may be set to zero, or may be changed to a value in the vicinity of zero. When the coasting mode is switched, if the indicated torque is a value in the vicinity of zero, the indicated torque calculation unit 23 does not have to change the value of the indicated torque. When the value of the indicated torque approaches zero, the torque output to the drive wheels 2 approaches zero, and the traveling is shifted to a traveling close to inertial traveling.

In the inertial running mode, the instruction torque calculation unit 23 next calculates the instruction torque that follows the target torque by adding a second change amount limit that is stronger than the first change amount limit in the normal driving mode. The calculation of the indicated torque that follows the target torque means that the indicated torque is calculated so that the indicated torque approaches the target torque. The second change amount limit is set to a strong value such that the indicated torque does not catch up with the target torque even if the standard acceleration or deceleration operation is continued throughout the standard coasting duration, for example. Will be done. For example, when the tilt limit is applied as the second change amount limit, a time change rate of several percent of the maximum torque in 5 seconds may be adopted as the tilt limit value. Further, when a first-order lag filter is applied as the second change amount limit, a time constant of about 60% in 5 seconds may be adopted. Due to the second change amount limitation, the indicated torque gradually increases or decreases even when the driver performs a large acceleration operation or deceleration operation. That is, delicate acceleration / deceleration adjustment is possible by a large acceleration operation or a large deceleration operation by the driver.

The mode control unit 21 switches the traveling mode from the normal traveling mode to the inertial traveling mode based on the operation of the inertial traveling mode button 14 by the driver. Further, the mode control unit 21 releases the inertial running mode when the difference between the target torque and the indicated torque becomes equal to or less than the threshold value during the coasting running mode. The threshold value is set to a value indicating that the target torque and the indicated torque are approaching. When the mode control unit 21 switches to the coasting mode, if the difference between the target torque and the indicated torque is already equal to or less than the threshold value, the mode control unit 21 once deviates from the indicated torque and then the above difference becomes the threshold value. Hysteresis control may be performed so that the inertial running mode is canceled when the following occurs.

In addition to the above conditions, the mode control unit 21 cancels the inertial running mode when the vehicle speed becomes zero (stopped) during the coasting running mode. Further, the mode control unit 21 sets the inertial running mode when the operating amount of the accelerator pedal 12 exceeds the release threshold value and when the operating amount of the brake pedal 11 exceeds the threshold value during the inertial running mode. You may cancel it. The release threshold value may be arbitrarily set by the designer as a threshold value for separating the continuation and the release of the meandering travel mode. However, the release threshold is set so that the range below the release threshold (the range of the amount of operation for continuing the driving mode) includes the amount of operation of the accelerator pedal 12 that realizes acceleration during normal driving on general roads and highways. Will be done.

In addition to performing drive control so that the indicated torque is output from the drive wheels 2, the drive control unit 24 includes an ISS (Idling Stop and Start) control unit 24a, and the ISS control unit 24a activates idling stop control. You can switch between hibernation and hibernation. When the control of the ISS control unit 24a is activated, the ISS control unit 24a repeatedly determines whether or not the engine 6 is operating when the indicated torque is zero or less, and when the indicated torque is zero or less and the engine 6 is operating, It is determined that the engine 6 is idling, and the engine 6 is stopped. In the normal driving mode, the drive control unit 24 activates the idling stop control of the ISS control unit 24a when a predetermined time has elapsed from the stop or when the engine running is switched to the motor running.

<Driving operation when signal is stopped>
Subsequently, a driving example in which the inertial driving mode can be beneficially used will be shown. FIG. 3 is a timing chart showing an operation example when the inertial traveling mode is used when the signal is stopped. In the example of FIG. 3, the one-pedal operation mode is selected as the operation operation mode.

While traveling in the normal traveling mode, when the driver confirms a signal to stop forward (timing t1), the accelerator pedal 12 is released. By this operation, the target torque and the indicated torque are reduced from the acceleration torque to the deceleration torque, and the vehicle speed is reduced. Then, when the vehicle speed to be maintained is reached, the driver presses the inertial driving mode button 14 (timing t2). Then, the traveling mode shifts to the inertial traveling mode, and the indicated torque approaches zero. In the example of FIG. 3, since the operating amount of the accelerator pedal 12 is zero and the target torque is a negative value M1 immediately before the timing t2, the indicated torque and the target torque are separated immediately after the timing t2.

In the coasting mode period T1, the indicated torque gradually approaches the target torque due to the second change amount limitation, which is strongly limited. In the example of FIG. 3, since the target torque is a negative value M1, the indicated torque becomes a negative value and gradually decreases. Along with this, in the period T1, a gradual deceleration torque is output to the drive wheels 2, and the vehicle speed gradually decreases.

If a gentle deceleration torque is not required during the coasting mode period T1, the driver can reduce the deceleration torque by depressing the accelerator pedal 12 halfway. Since the operating amount of the accelerator pedal 12 is relatively large with respect to the adjusting amount of the deceleration torque, delicate adjustment can be performed with good driving operability.

When the vehicle speed is felt to be low before approaching the stop line (timing t3), the driver depresses the accelerator pedal 12 to the extent that acceleration torque can be obtained in the normal driving mode. During this stepping, the target torque increases and the difference from the indicated torque decreases, so that the inertial traveling mode is canceled and the normal traveling mode is switched to (timing t4). When switching to the normal driving mode, the target torque and the indicated torque are close to each other with a small value, so that the indicated torque changes continuously before and after switching to the normal driving mode, and the driver feels comfortable with the vehicle 1 Can be accelerated. Furthermore, when accelerating, the vehicle is switched to the normal driving mode, so the vehicle speed can be recovered without a feeling of sluggishness.

Then, when the vehicle speed increases and approaches the stop line (timing t5), the driver returns the accelerator pedal 12 to the position where the operation amount is zero, so that the deceleration torque is applied and the vehicle is operated in the same manner as in the normal one-pedal operation. 1 can be stopped.

If an appropriate vehicle speed is obtained until the vehicle approaches the stop line, the driver continues the coasting mode until the vehicle stops. Then, by depressing the accelerator pedal 12 to a neutral position of one-pedal operation before stopping, the traveling mode can be returned to the normal traveling mode without applying a large acceleration / deceleration. The driver can recognize that he / she has returned to the normal driving mode from the display of the driving mode display unit 16. Then, by returning the accelerator pedal 12 to the position where the operation amount is zero, the deceleration torque is applied and the vehicle can be stopped in the same manner as in the normal one-pedal operation.

As a comparative example, a case where the normal driving mode in the one-pedal operation is continued from the timing t1 when the signal to be stopped is confirmed to the timing t4 when the vehicle is stopped will be described. In this case, if the driver returns the accelerator pedal 12 to the position where the operation amount is zero at the timing t1, a large deceleration torque is generated. On the contrary, if the driver depresses the accelerator pedal 12 beyond the neutral position, acceleration torque is generated. Therefore, in order to maintain an appropriate vehicle speed, a delicate operation of the accelerator pedal 12 is required. It is difficult to stop the accelerator pedal 12 in a neutral position, and unnecessary acceleration and deceleration occur. The operation is repeated and the electricity cost worsens.

As described above, according to the vehicle 1 of the first embodiment, the traveling mode can be switched between the normal traveling mode and the inertial traveling mode. Further, in the inertial running mode, once the indicated torque approaches zero, a second change amount limit stronger than the first change amount limit in the normal running mode is added, and the indicated torque following the target torque is calculated. .. Therefore, when a slight deceleration or a slight acceleration is required when traveling while maintaining the speed in the inertial running mode, the driver operates the accelerator pedal 12 relatively large and gently according to the request. Torque adjustment can be performed. Therefore, good driving operability is realized when a slight deceleration or a slight deceleration is desired while maintaining the speed.

Further, according to the vehicle 1 of the first embodiment, the driver can switch to the inertial driving mode by pressing the inertial driving mode button 14. The request for switching to the inertial driving mode may occur not only in the road condition but also in the driver's condition such as the tiredness of the leg that operates the pedal. With the above configuration, it is possible to respond to such a switching request.

Further, according to the vehicle 1 of the first embodiment, the mode control unit 21 switches from the inertial traveling mode to the normal traveling mode when the difference between the indicated torque and the target torque becomes equal to or less than the threshold value. When the condition for releasing the inertial running mode is when the accelerator pedal 12 is depressed by a considerable amount or when the brake pedal 11 is depressed by a considerable amount, unnecessary acceleration or unnecessary deceleration often occurs at the time of release. .. On the other hand, according to the condition of the first embodiment, since the indicated torque is gently continuous before and after returning to the normal traveling mode, unnecessary deceleration or unnecessary acceleration is unlikely to occur. Therefore, the driving operability when returning to the normal driving mode can be improved, and the fuel consumption or the electricity cost can be improved by reducing unnecessary loss. When the difference between the indicated torque and the target torque is less than or equal to the threshold value, when the absolute value of the difference is less than or equal to the first threshold value of the positive value, the indicated torque-the second threshold value of the positive value of the target torque is ~. When it becomes zero, when the target torque-instructed torque becomes the third threshold value to zero of the positive value, when the target torque = the indicated torque, or when any two or more of these are combined. included. The first threshold value to the third threshold value may be the same value or different values.

(Embodiment 2)
The vehicle of the second embodiment is the same as that of the first embodiment except that the control process of the mode control unit 21 is different.

FIG. 4 is a flowchart showing a procedure of the traveling mode switching process executed by the mode control unit of the second embodiment. FIG. 4 shows from step S1 which is the control content in the normal traveling mode, and omits from step S5 which is the control content in the inertial traveling mode. The mode control unit 21 of the second embodiment repeats the process (step S2) of determining whether or not the inertial traveling mode button 14 is pressed during the normal operation mode, and when the inertial traveling mode button 14 is operated, the vehicle travels. The mode is switched to the inertial running mode (step S3). By this switching, the instruction torque calculation unit 23 brings the instruction torque close to zero, switches the method of calculating the instruction torque to a method corresponding to the inertial running mode, and realizes the inertial running mode.

Subsequently, the mode control unit 21 of the second embodiment sends a request for switching to the one-pedal operation mode to the target torque calculation unit 22 (step S4). By the process of step S4, the operation mode of the accelerator pedal 12 is switched from the normal operation mode to the one-pedal operation mode. The switch to the one-pedal operation mode is notified to the driver by the display of the one-pedal display unit 15. Then, the mode control unit 21 returns the process to step S1.

By switching from the normal operation mode to the one-pedal operation mode, the relationship between the operation amount of the accelerator pedal 12 and the target torque is switched from the relationship shown in FIG. 2 (A) to the relationship shown in FIG. 2 (B). This switching corresponds to a shift in which the target torque corresponding to the zero operation amount of the accelerator pedal 12 is negative and the absolute value becomes large.

<Driving operation when signal is stopped>
Subsequently, a running example of the vehicle of the second embodiment will be shown. FIG. 5 is a timing chart showing an operation example when the inertial traveling mode of the second embodiment is used when the signal is stopped. In the example of FIG. 5, the normal operation mode is selected as the initial operation operation mode.

When the normal operation mode is selected and the driver confirms a signal to stop forward while driving in the normal driving mode (timing t11), the accelerator pedal 12 is returned, the brake pedal 11 is operated, and the vehicle speed is increased. To adjust. Then, the inertial traveling mode button 14 is pressed (timing t12). Then, the mode is switched to the inertial running mode, and the accelerator pedal 12 is switched to the one-pedal operation mode. Then, after that, the same operation operation as in FIG. 2 of the first embodiment is realized.

As a comparative example, a case where the normal operation mode is continued even after switching from the normal driving mode to the inertial driving mode during traveling in the normal operation mode will be described. Even in this case, if the driver wishes to generate a slight deceleration torque during the period T1 of the coasting mode, the target torque is lowered to the deceleration side by operating the brake pedal 11. It is possible to obtain the same vehicle behavior as the driving operation of 5. However, when the operation of the brake pedal 11 is used as a condition for releasing the inertial running mode, it is somewhat difficult to operate the brake pedal 11 to reduce the target torque to the deceleration side while the coasting running mode is maintained. ..

On the other hand, as in the second embodiment, when the coasting mode is switched to, the driving operation mode is switched to the one-pedal operation mode, so that the target torque on the deceleration side can be generated depending on the operation amount of the accelerator pedal 12. For example, by pressing the inertial running mode button 14 with the accelerator pedal 12 open, the mode is switched to the inertial running mode with the target torque being negative. Therefore, after that, by operating the accelerator pedal 12 relatively large without using the brake pedal 11, the deceleration torque slightly generated in the inertial traveling mode can be adjusted to be large or small. That is, the vehicle speed can be decelerated and adjusted delicately with good driving operability. Then, by depressing the accelerator pedal 12 to a position where acceleration torque is generated, the target torque and the indicated torque come close to each other, and the inertial traveling mode can be released while suppressing the occurrence of unnecessary acceleration or unnecessary deceleration.

Further, in the second embodiment, by pressing the inertial travel mode button 14 while traveling with the accelerator pedal 12 greatly depressed in the normal operation mode, the target torque is switched to the inertial travel mode and the indicated torque is instructed. Approaches zero. Therefore, after that, by operating the accelerator pedal 12 relatively large, the acceleration torque slightly generated in the inertial traveling mode can be adjusted to be large or small. That is, the vehicle speed can be delicately accelerated and adjusted with good driving operability. Then, by depressing the accelerator pedal 12 to the position where the deceleration torque is generated, the target torque and the indicated torque come close to each other, and the coasting mode can be released while suppressing the occurrence of unnecessary acceleration or unnecessary deceleration. ..

As described above, according to the vehicle of the second embodiment, when the vehicle is switched to the inertial driving mode, the driving operation mode is switched to the one-pedal operation mode, so that a slight deceleration request or a slight acceleration request is made during the traveling in the inertial driving mode. If this happens, the accelerator pedal 12 can be operated to meet these demands.

(Embodiment 3)
The vehicle of the third embodiment is the same as that of the second embodiment except that a part of the control process of the instruction torque calculation unit 23 is different.

FIG. 6 is a flowchart showing an initial setting process at the time of switching the inertial running mode executed by the instruction torque calculation unit of the third embodiment. The initial setting process of FIG. 6 is a process of setting the control parameters used for the calculation process of the indicated torque in the inertial driving mode, and when the mode control unit 21 switches the traveling mode from the normal traveling mode to the inertial traveling mode. Will be executed.

The instruction torque calculation unit 23 of the third embodiment determines whether the operation operation mode has been switched from the normal operation mode to the one-pedal operation mode when the inertial running mode is switched (step S11). Also in the vehicle of the third embodiment, as shown in the second embodiment, when the traveling mode is switched to the inertial traveling mode, the driving operation mode is normally switched to the one-pedal operation mode. On the other hand, in the vehicle of the third embodiment, the driving operation mode is the normal operation mode even when the driving mode is switched to the inertial driving mode depending on the setting conditions of the system, the vehicle state, the driving condition, and various other conditions. It may be maintained as it is. Therefore, in step S11, it is determined which case is selected according to the above conditions.

As a result of the determination in step S11, if it is determined that there is no switching to the one-pedal operation mode, the instruction torque calculation unit 23 sets the first value as the value of the second change amount limit (step S12). On the other hand, as a result of the determination in step S11, if it is determined that there is a switch to the one-pedal operation mode, the instruction torque calculation unit 23 indicates a second change amount limit value stronger than the first value. The value of is set (step S13). The first value and the second value are both values indicating a stronger limit than the value of the first change amount limit.

When the initial setting process is completed, the instruction torque calculation unit 23 executes the instruction torque calculation process in the inertial running mode using the value of the second change amount limit set in the initial setting process.

As described above, according to the vehicle of the third embodiment, when switching to the coasting driving mode, the target torque calculation unit 22 switches the driving operation mode from the normal operation mode to the one-pedal operation mode, and maintains the normal operation mode. One of the cases is selected. Then, according to these cases, the instruction torque calculation unit 23 switches the control parameter used when calculating the instruction torque in the inertial running mode. That is, the value of the second change amount limit is set to a value with a stronger limit in the former case than in the latter case. When switching to the coasting mode, the accelerator pedal 12 is often left open. When the accelerator pedal 12 is released in the normal operation mode when the coasting mode is switched to, the target torque becomes a small value. On the other hand, when the accelerator pedal 12 is released in the one-pedal operation mode when the inertial running mode is switched, the target torque is negative and the absolute value becomes a relatively large value.

If the absolute value of the target torque is large and the coasting mode continues for a long time, the indicated torque departs from zero and approaches the large value of the target torque even if the second change amount limit is applied. In this case, the running is far from the coasting running. On the other hand, if the target torque is a small value, the indicated torque stays in the vicinity of zero because the second change amount limit may be applied even if the coasting mode continues for a long time.

Therefore, by making the value of the second change amount limit different in the above two cases, it is possible to prevent the indicated torque from deviating significantly from zero in the inertial running mode in the one-pedal operation mode. That is, by setting the second change amount limit to a different value depending on the driving operation mode, the method of calculating the indicated torque of the inertia driving mode suitable for each different driving operation mode is selected, and the inertia driving mode suitable for the different driving operation mode is selected. Can be realized.

(Embodiment 4)
The vehicle of the fourth embodiment is the same as the first to third embodiments except that the control process of the drive control unit 24 is different.

FIG. 7 is a flowchart showing a traveling mode switching process executed by the drive control unit of the fourth embodiment. The travel mode switching process of FIG. 7 is a process executed by the drive control unit 24 when the mode control unit 21 notifies the vehicle to switch the travel mode. In the traveling mode switching processing, the drive control unit 24 determines whether the traveling mode is switched from the normal traveling mode to the inertial traveling mode (step S21) or vice versa (step S22). In FIG. 7, the process when the mode is switched to the normal operation mode is omitted.

As a result of the determination in step S21, if it is determined that the vehicle is switched to the inertial traveling mode, the drive control unit 24 activates the idling stop control on the ISS control unit 24a (step S23). Then, the processing at the time of switching the traveling mode is terminated.

If the idling stop control is not activated while the engine is running and the mode is switched to the coasting mode, the engine 6 continues to be driven until the vehicle stops after running close to the coasting running, resulting in deterioration of fuel efficiency. On the other hand, according to the vehicle of the fourth embodiment, the idling stop control is activated when the mode is switched to the coasting mode, so that the indicated torque becomes close to zero when the mode is switched to the coasting mode while the engine is running. Occasionally, idling stop is implemented promptly. After that, when a slight acceleration torque or a slight deceleration torque is output, it is realized by driving the traveling motor 3. Therefore, it is possible to avoid that the engine 6 continues to be in a state close to idling operation during traveling close to inertial driving, which causes deterioration of fuel efficiency.

(Embodiment 5)
The vehicle of the fifth embodiment is the same as that of the first to fourth embodiments except that a part of the control process of the instruction torque calculation unit 23 is different.

FIG. 8 is a flowchart of a button operation input process executed by the mode control unit and the instruction torque calculation unit of the fifth embodiment. The process of FIG. 8 is started by the mode control unit 21 when the inertial traveling mode button 14 is pressed. When the button pressing process is started, the mode control unit 21 determines whether the vehicle is currently in the coasting mode (step S31), and if NO, switches the traveling mode to the inertial traveling mode (step S32). This process ends.

On the other hand, if the determination result is YES in step S31, the mode control unit 21 notifies the instruction torque calculation unit 23 of the button press (step S33). Based on this notification, the indicated torque calculation unit 23 initializes the indicated torque to approach zero (step S34). Then, the button pressing process ends.

If the inertial traveling mode continues for a long time, the accelerator pedal 12 is operated during that time, and the indicated torque may gradually change within the range of the second change amount limit, and the absolute value of the indicated torque may increase. Even in such a case, according to the vehicle of the fifth embodiment, by pressing the inertial traveling mode button 14 again, the indicated torque can be brought close to zero again as in the case of switching the inertial traveling mode. Then, it is possible to return to the running close to the inertia running. In this way, when a request to bring the indicated torque closer to zero occurs again in the inertial driving mode, the request can be met by pressing the inertial driving mode button 14, so that the convenience of the inertial driving mode is further enhanced. Can be improved.

Although the fifth embodiment shows a configuration in which the inertial running mode button 14 is used as both an operation unit for switching to the inertial running mode and an operation unit for initializing the indicated torque during the inertial running mode, both operations are shown. The parts may be provided separately.

Each embodiment of the present invention has been described above. However, the present invention is not limited to the above embodiment. For example, in the above embodiment, the example in which the vehicle is an HEV is shown, but the vehicle may be an engine vehicle or an electric vehicle without an engine. Further, in the above embodiment, the configuration example in which the indicated torque is output to the drive wheels by driving the traveling motor or the engine is shown, but the control for disconnecting the driving wheels and the engine or the driving wheels and the traveling motor via a clutch is performed. A configuration in which the torque of the drive wheels is controlled may be used in combination. Further, in the above embodiment, the one-pedal operation mode is included in the accelerator pedal operation mode, but the accelerator pedal operation mode may be only the normal operation mode. In addition, the details shown in the embodiment can be appropriately changed without departing from the spirit of the invention.

1 Vehicle 2 Drive wheels 3 Travel motor 4 Inverter 6 Engine 7 Auxiliary equipment 10 Driving operation unit 11 Brake pedal 12 Accelerator pedal 14 Inertial travel mode button 15 One pedal display unit 16 Driving mode display unit 20 Control unit 21 Mode control unit 22 Target torque calculation Part 22a Target torque data table 23 Instructed torque calculation unit (1st instructed torque calculation unit, 2nd instructed torque calculation unit)
24 Drive control unit 24a ISS control unit

Claims (7)

A mode control unit that can switch between a first running mode in which the torque changes according to the driving operation and a second running mode in which the running is closer to coasting than the first running mode.
A target torque calculation unit that calculates the target torque based on the driving operation,
A first instruction torque calculation unit that calculates an instruction torque that follows the target torque by applying a first change amount limit in the first travel mode.
A second indicated torque calculation unit that calculates an indicated torque that follows the target torque by applying a second change amount limit that is stronger than the first change amount limit after the indicated torque is brought close to zero in the second traveling mode. When,
A drive control unit that drives the power source or braking unit so that the calculated indicated torque is output to the drive wheels.
A vehicle characterized by being equipped with. Equipped with a first operation unit for switching driving modes that can be operated by the driver
The vehicle according to claim 1, wherein the mode control unit switches from the first traveling mode to the second traveling mode based on the operation of the first operating unit. The mode control unit is characterized by switching from the second travel mode to the first travel mode when the difference between the instruction torque calculated by the second instruction torque calculation unit and the target torque becomes equal to or less than a threshold value. The vehicle according to claim 1 or 2. When switching from the first traveling mode to the second traveling mode, the target torque calculation unit shifts the target torque corresponding to the zero accelerator operating amount toward a negative and larger absolute value. The vehicle according to any one of claims 1 to 3, wherein the relationship between the operating amount and the target torque is changed. When switching from the first traveling mode to the second traveling mode, the target torque calculation unit shifts the target torque corresponding to the zero accelerator operating amount to the direction in which the absolute value becomes larger in the negative direction. It is possible to switch between the case of changing the relationship between the operation amount and the target torque and the case of not changing the relationship between the accelerator operation amount and the target torque under predetermined conditions.
The feature is that the value of the second change amount limit when the relationship is changed is set to a value having a stronger limit than the value of the second change amount limit when the relationship is not changed. The vehicle according to any one of claims 1 to 3. Equipped with an engine that generates power for driving
The drive control unit can activate idling stop control for stopping the engine when the engine is idling.
The vehicle according to any one of claims 1 to 5, wherein the drive control unit activates the idling stop control based on the switching of the traveling mode to the second traveling mode. .. Equipped with a second operation unit that can be operated by the driver
Claims 1 to 6 are characterized in that, when the second operation unit is operated during the second traveling mode, the second instruction torque calculation unit lowers the absolute value of the instruction torque again. The vehicle described in any one of the above.

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