WO2020026621A1

WO2020026621A1 - Vehicle control device

Info

Publication number: WO2020026621A1
Application number: PCT/JP2019/024080
Authority: WO
Inventors: 小倉　健太郎; 武史長岡
Original assignee: ボッシュ株式会社; ボッシュエンジニアリング株式会社
Priority date: 2018-08-02
Filing date: 2019-06-18
Publication date: 2020-02-06
Also published as: DE112019003902T5; CN112752688B; CN112752688A; JP7223762B2; JPWO2020026621A1

Abstract

Provided is a vehicle control device capable of smoothly replacing the braking force generated by a regenerative brake with the braking force generated by a hydraulic brake when a vehicle is decelerating. This vehicle control device (100) comprises: a regenerative braking torque control unit (230) that reduces target regenerative braking torque with a predetermined gradient when an engine speed index correlated with the rotational speed of an engine (20) satisfies a predetermined condition in a state in which regenerative braking torque is generated during fuel-cut control in which fuel injection into the engine (20) is stopped; and a hydraulic brake control unit (240) that sets, as target hydraulic brake torque, the difference between the required braking torque required by the driver of a vehicle (1) and the target regenerative braking torque.

Description

Vehicle control device

The present invention relates to a control device for a vehicle.

車両 Vehicles equipped with an internal combustion engine and a motor generator having a power generation function are known. When the vehicle decelerates, the motor generator functions as a power generation device that converts kinetic energy input from the driving wheel side into electric energy, and at the same time, transmits the rotational resistance generated during the power generation to the driving wheel side as a regenerative brake. Functions as a device. In the field related to a vehicle equipped with a motor generator, various technologies for controlling a braking force of the vehicle have been proposed.

For example, Patent Literature 1 discloses a hybrid vehicle and an electric vehicle that can obtain a braking force desired by a driver by changing a hydraulic braking torque in accordance with a regenerative braking torque that changes according to a power generation amount of a motor generator. Discloses a brake system and a control method thereof.

JP 2008-056228 A

By the way, when the vehicle is decelerated, fuel injection to the engine may be stopped to improve fuel efficiency. In addition, in a state where the fuel injection is stopped, the regenerative braking by the motor generator may be preferentially used for a braking request of the vehicle.

In a vehicle in which the engine and the motor generator are directly connected (cannot be separated), the rotational resistance due to the regenerative driving of the motor generator becomes the load on the engine. .

In such a case, it is conceivable to perform control to gradually reduce the braking force by the regenerative brake and replace the decrease in the braking force by the regenerative brake with the braking force by the hydraulic brake.

As one of the controls for replacing the braking force by the regenerative brake with the braking force by the hydraulic brake, a method of reducing the braking force by the regenerative brake in accordance with the change in the engine speed can be considered.

However, when the vehicle is decelerated, the engine speed generally decreases with vertical fluctuations, and in this method, the braking force by the regenerative brake decreases with vertical fluctuations. On the other hand, since the braking force by the hydraulic brake is controlled by changing the hydraulic pressure flowing through the hydraulic circuit, a certain time lag occurs in controlling the braking force by the hydraulic brake.

Therefore, when such a control method is applied at the time of deceleration of the vehicle, the braking force of the entire vehicle is not stabilized, and the vehicle may be vibrated.

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to make it possible to smoothly replace a braking force by a regenerative brake with a braking force by a hydraulic brake when the vehicle is decelerated. It is to provide a control device for a vehicle.

In order to solve the above problems, according to an aspect of the present invention, a regenerative braking torque and a regenerative braking torque generated by a motor generator mounted on a vehicle including an engine and a motor generator connected in series and a hydraulic brake operated by hydraulic pressure are provided. A control device for a vehicle that controls a hydraulic brake torque generated by a hydraulic brake, wherein the regenerative braking torque is generated during fuel cut control for cutting fuel injection to an engine, and is correlated with an engine speed. A regenerative braking torque control unit that reduces the target regenerative braking torque at a predetermined gradient when the engine speed index satisfies a predetermined condition; and a torque between a required braking torque requested by the driver of the vehicle and the target regenerative braking torque. And a hydraulic brake control unit that sets a difference between the two as a target hydraulic brake torque. That.

As described above, according to the present invention, when the vehicle is decelerated, the braking force by the regenerative brake can be smoothly replaced with the braking force by the hydraulic brake.

FIG. 1 is a schematic diagram illustrating a configuration example of a vehicle to which a vehicle control device according to a first embodiment of the present invention can be applied. FIG. 2 is a block diagram illustrating a configuration example of a vehicle control device according to the embodiment. FIG. 5 is an explanatory diagram illustrating an operation example of a control device for a vehicle according to a comparative example. It is an explanatory view showing an operation example of the control device for the vehicle according to the embodiment. It is an explanatory view showing an operation example of the control device for the vehicle according to the embodiment. It is a flow chart which shows an example of operation of the control device of the vehicles concerning the embodiment. It is a schematic diagram showing a configuration example of a vehicle to which a control device for a vehicle according to a second embodiment of the present invention can be applied. FIG. 2 is a block diagram illustrating a configuration example of a vehicle control device according to the embodiment. It is an explanatory view showing an operation example of the control device for the vehicle according to the embodiment. It is an explanatory view showing an operation example of the control device for the vehicle according to the embodiment. It is a flow chart which shows an example of operation of the control device of the vehicles concerning the embodiment.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the specification and the drawings, components having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

<1. First Embodiment>
A vehicle control device according to a first embodiment of the present invention will be described.

[1-1. Example of overall configuration of vehicle]
First, an overall configuration example of a vehicle to which the vehicle control device according to the present embodiment can be applied will be described with reference to FIG. FIG. 1 is a schematic diagram showing a vehicle 1 provided with a vehicle control device 100. Hereinafter, an example of the overall configuration of the vehicle 1 will be described separately for the power unit 10 and the control device 100.

(1-1-1. Power unit)
As shown in FIG. 1, the power unit 10 of the vehicle 1 includes an engine 20 as a power source. The power unit 10 includes a motor generator 30 that functions as a starter that performs cranking when the engine 20 starts. Motor generator 30 also functions as a braking device during vehicle deceleration.

The engine 20 and the motor generator 30 are connected in series via, for example, a coupling. The power unit 10 includes a manual stepped transmission mechanism 50 connected to the motor generator 30 via the clutch mechanism 40. The stepped transmission mechanism 50 is connected to the drive wheels 60 via a differential mechanism or the like.

The battery 32 is connected to the motor generator 30 via the inverter 34. Inverter 34 controls motor generator 30 according to a control signal input from control device 100 described later.

When the motor generator 30 is controlled as a starter, power is supplied from the battery 32 to the motor generator 30 via the inverter 34. Motor generator 30 performs cranking using the supplied power.

When the motor generator 30 is controlled as a braking device (regenerative control), the motor generator 30 converts rotational energy input from the drive wheels 60 into electric energy. Motor generator 30 transmits the rotational resistance generated during the conversion to drive wheels 60 as regenerative braking torque.

(4) By controlling the exciting current flowing through the rotor of the motor generator 30 by the inverter 34, the braking force (regenerative braking torque) by the regenerative brake is controlled. The electric energy converted from the rotational energy is supplied from the motor generator 30 to the battery 32 via the inverter 34 as electric power.

The drive wheel 60 is provided with a hydraulic brake 62 operated by hydraulic pressure. As the hydraulic brake 62, for example, a disk brake is used. By controlling the hydraulic pressure supplied to the hydraulic brake 62, the braking force (hydraulic brake torque) by the hydraulic brake 62 is controlled.

油圧 The hydraulic pressure supplied to the hydraulic brake 62 is controlled by the hydraulic unit 70. The hydraulic unit 70 includes an oil passage for supplying oil pressure from a master cylinder (not shown) to the hydraulic brake 62, a pump driven by a motor to discharge brake fluid, and a control valve such as a solenoid valve for adjusting opening and closing of the oil passage. And are provided. The hydraulic pressure supplied to the hydraulic brake 62 is controlled by controlling the drive of the pump and the control valve by a brake controller 120 described later.

The clutch mechanism 40 switches the connection state between the motor generator 30 and the stepped transmission mechanism 50, that is, the connection state between the engine 20 and the stepped transmission mechanism 50. As the clutch mechanism 40, for example, a wet multi-plate clutch is used. By controlling the hydraulic pressure supplied to the clutch mechanism 40, the clutch mechanism 40 is engaged or released.

(4) When the clutch mechanism 40 is engaged, the engine 20 and the stepped transmission mechanism 50 are connected, and the drive wheels 60 are connected to the engine 20 and the motor generator 30. On the other hand, when the clutch mechanism 40 is released, the connection between the engine 20 and the stepped transmission mechanism 50 is released, and the engine 20 and the motor generator 30 are disconnected from the drive wheels 60.

In the above description, an example is described in which the engine 20 and the motor generator 30 are connected in series via a coupling. However, the engine 20 and the motor generator 30 may be connected via a belt and a pulley.

(1-1-2. Control device)
The overall configuration of the control device 100 of the vehicle 1 will be described. As shown in FIG. 1, the vehicle 1 includes various controllers including a microcomputer and the like in order to control an operation state of the power unit 10. As various controllers, an engine controller 110 and a brake controller 120 are provided.

These controllers are communicably connected to each other via one or a plurality of in-vehicle networks such as CAN (Controller Area Network) or LIN (Local Internet), and perform braking force displacement control in cooperation with each other.

A part or all of each controller may be configured by, for example, a microcomputer, a microprocessor unit, or the like. In addition, a part or all of each controller may be configured by an updatable device such as firmware, or may be a program module or the like executed by a command from a CPU or the like.

Each controller includes a storage device (not shown) for storing a program executed by a microcomputer or the like, parameters used for various calculations, detection data, information on calculation results, and the like.

The storage device may be a storage device such as a random access memory (RAM) or a read only memory (ROM), or a storage device such as a hard disk drive (HDD), a CD-ROM, or a storage device. .

ブレーキ A brake sensor 81, an accelerator sensor 83, a clutch sensor 85, and an engine speed sensor 87 are connected to the engine controller 110. A brake sensor 81 is connected to the brake controller 120.

The brake sensor 81 detects the operation amount of the brake pedal. The accelerator sensor 83 detects an operation amount of an accelerator pedal. The clutch sensor 85 detects the operation amount of the clutch pedal. The engine speed sensor 87 detects the engine speed, which is the rotation speed of the crankshaft.

(4) The engine controller 110 outputs a control signal to a throttle valve, an injector, and the like of the engine 20 to control engine torque, engine speed, and the like. When the vehicle 1 is decelerated, the engine controller 110 stops the fuel injection while the engine 20 continues to rotate without stopping due to the rotational force of the drive wheels 60 even if the fuel injection is stopped (hereinafter, “fuel injection”). Also called "cut control.").

{Circle around (4)} When the engine speed approaches an area where engine stall may occur due to a decrease in the engine speed, fuel injection is restarted.

{Circle around (4)} Engine controller 110 outputs a control signal to inverter 34 connected to motor generator 30 to control the driving of motor generator 30. When the vehicle 1 is decelerating, the engine controller 110 outputs a control signal to the inverter 34 based on a control command from the brake controller 120, and controls the regenerative braking torque of the motor generator 30.

The brake controller 120 controls the regenerative braking torque by the motor generator 30 and the hydraulic brake torque by the hydraulic brake 62 to control the braking force of the vehicle 1.

The brake controller 120 sets the control target (target regenerative braking torque) of the motor generator 30 based on the information transmitted from each sensor and the engine controller 110. Brake controller 120 outputs a control command related to motor generator 30 to engine controller 110 based on the set control target.

The brake controller 120 sets a difference obtained by subtracting the regenerative braking torque by the motor generator 30 from the braking force (requested braking torque) required for the vehicle 1 as a control target (a target hydraulic brake torque) of the hydraulic brake 62. The brake controller 120 outputs a control signal to a pump and a control valve provided in the hydraulic unit 70 based on the control target, and controls a hydraulic brake torque and the like.

In the present embodiment, when a driver or the like performs a brake operation during fuel cut control, the brake controller 120 causes the motor generator 30 to generate regenerative braking torque to decelerate the vehicle 1.

{Circle around (2)} When the engine speed is reduced and the operating state is likely to cause an engine stall, the brake controller 120 performs the braking force replacement control for gradually replacing the regenerative braking torque with the hydraulic brake torque.

In the vehicle 1 in which the engine 20 and the motor generator 30 are connected in series, when the clutch mechanism 40 is in the engaged state, the driving wheels 60 are connected to the engine 20 and the motor generator 30.

In this state, when the accelerator pedal is released and the required driving torque of the vehicle 1 becomes zero, the rotational force of the drive wheels 60 is transmitted to the engine 20 so that even if fuel is not injected into the engine 20, There is an operation region where the engine 20 can rotate without causing a stall.

では In such an operation range of the engine 20, the engine controller 110 performs a fuel cut control for stopping the fuel injection to the engine 20 in order to improve the fuel efficiency of the vehicle 1.

場合 When the driver operates the brake pedal during the fuel cut control, the brake controller 120 generates regenerative braking torque. During the fuel cut control, the output torque from the engine 20 is zero, and efficient regenerative power generation by the motor generator 30 is possible. For this reason, the brake controller 120 generates the braking force of the vehicle 1 by the regenerative control of the motor generator 30 without using the hydraulic brake.

(4) When the vehicle 1 further decelerates and the engine speed approaches an area where the engine may be stalled, the engine controller 110 ends the fuel cut control and restarts the fuel injection. After the fuel injection is restarted, the fuel injection amount is controlled to the minimum necessary amount to keep the engine speed at the minimum speed (for example, idling speed) at which there is no risk of engine stall.

Here, when the vehicle 1 further decelerates and the regenerative braking torque is not 0 when the engine speed reaches the idling speed, the rotational resistance of the motor generator 30 becomes a load on the engine 20 and engine stall occurs. May occur.

Therefore, the brake controller 120 replaces the braking torque of the vehicle 1 with the hydraulic braking torque from the regenerative braking torque before the engine speed reaches the idling speed. Hereinafter, a specific example of the control device 100 that enables the execution of the braking force replacement control will be described.

[1-2. Specific example of control device]
A specific example of the vehicle control device 100 according to the present embodiment will be described. FIG. 2 is an explanatory diagram illustrating a functional configuration of a portion related to the braking force replacement control in the control device 100 including the engine controller 110 and the brake controller 120 illustrated in FIG.

The control device 100 includes a control start determination unit 210, a maximum regenerative braking torque setting unit 220, a regenerative braking torque control unit 230, and a hydraulic brake control unit 240.

制御 Control device 100 also acquires signals output from brake sensor 81, accelerator sensor 83, clutch sensor 85, and engine speed sensor 87. Various types of information indicated by the acquired signals are stored in a storage device (not shown).

(Control start determination unit)
For example, the engine controller 110 functions as the control start determination unit 210. The control start determination unit 210 determines whether to start the braking force replacement control based on information from various sensors.

{Specifically, the control start determination unit 210 determines whether or not the engine speed as an engine speed index acquired from the engine speed sensor 87 has reached the first speed during vehicle deceleration. When the engine speed decreases and reaches the first speed, the control start determination unit 210 determines to start the braking force replacement control.

Here, if the fuel injection is performed during the regenerative control of the motor generator 30, the output torque of the engine 20 is applied to the drive shaft to which the regenerative braking torque is applied, and the fuel efficiency is reduced. Therefore, it is preferable that the braking force replacement control be started before the fuel injection is restarted.

Note that an appropriate reference rotation speed higher than the idling rotation speed may be used as the first rotation speed. This is because when the purpose is to prevent engine stall, the braking force replacement control may be started before the engine speed reaches the idling speed.

However, when the first rotation speed is excessively higher than the rotation speed at which fuel injection is restarted (fuel injection restart rotation speed), some regenerative braking torques are not increased even though the fuel consumption is reduced. It is replaced by torque, and the regenerative efficiency decreases. For this reason, it is preferable that the first rotation speed is, for example, a rotation speed obtained by adding an appropriate offset value to the fuel injection restart rotation speed.

(Maximum regenerative braking torque setting section)
For example, the engine controller 110 functions as the maximum regenerative braking torque setting unit 220. The maximum regenerative braking torque setting unit 220 sets the maximum regenerative braking torque that can be generated by the motor generator 30 as described below when the control start determination unit 210 determines to start the braking force replacement control.

In the following description, the maximum regenerative braking torque that can be generated by motor generator 30 is referred to as the maximum regenerative braking torque.

First, the maximum regenerative braking torque setting unit 220 sets the regenerative braking torque generated by the motor generator 30 as the initial value of the maximum regenerative braking torque at the time when the control start determination unit 210 determines to start the braking force replacement control. .

{Circle around (4)} The maximum regenerative braking torque setting unit 220 monotonically decreases the maximum regenerative braking torque with a predetermined gradient as time passes. At this time, the maximum regenerative braking torque setting unit 220 may reduce the maximum regenerative braking torque so that the gradient becomes linear.

When the maximum regenerative braking torque is not 0 when the engine speed reaches the second rotation speed, the maximum regenerative braking torque setting unit 220 determines the rate of decrease of the maximum regenerative braking torque so that the angle of the gradient increases. May be raised.

That is, if the motor generator 30 is driven to rotate even after the engine speed reaches the idling speed, the rotational resistance of the motor generator 30 may become a load on the engine 20 and cause engine stall.

For this reason, when it is determined that the maximum regenerative braking torque does not become 0 before the engine speed reaches the idling speed, the gradient for decreasing the maximum regenerative braking torque is increased, and the maximum regenerative braking torque is quickly reduced to 0. Is preferable. The second rotation speed may be, for example, a rotation speed obtained by adding an appropriate offset value to the idling rotation speed.

Note that the maximum regenerative braking torque setting unit 220 does not necessarily need to change the gradient even when the maximum regenerative braking torque is not 0 when the engine speed reaches the second speed. .

For example, when the engine speed reaches the second speed, the maximum regenerative braking torque is in a region close to 0, and the maximum regenerative braking torque reaches 0 before the engine speed reaches the idling speed. When it is determined that this is the case, the maximum regenerative braking torque setting unit 220 does not need to change the gradient.

(Regenerative braking torque control unit)
For example, the engine controller 110 and the brake controller 120 function as the regenerative braking torque control unit 230. Regenerative braking torque control section 230 controls the regenerative braking torque generated by motor generator 30 based on the maximum regenerative braking torque set in maximum regenerative braking torque setting section 220 and information from various sensors. The regenerative braking torque control unit 230 controls the overall braking force of the vehicle 1 in cooperation with the hydraulic brake control unit 240.

The regenerative braking torque control unit 230 calculates the required braking torque of the vehicle 1 based on, for example, the operation amount of the brake pedal acquired from the brake sensor 81. Further, regenerative braking torque control section 230 compares the required braking torque with the maximum regenerative braking torque, and sets a smaller value as a target value (a target regenerative braking torque) of the regenerative braking torque that causes motor generator 30 to generate a smaller value. decide. Regenerative braking torque control section 230 controls motor generator 30 via inverter 34 based on the determined regenerative braking torque. Thereby, the regenerative braking torque of motor generator 30 is controlled.

(Hydraulic brake control unit)
For example, the brake controller 120 functions as the hydraulic brake control unit 240. The hydraulic brake control unit 240 sets the difference between the required braking torque and the target regenerative braking torque as the target hydraulic brake torque for causing the hydraulic brake 62 to generate.

In other words, the hydraulic brake control unit 240 sets the target hydraulic brake torque such that the total torque of the target regenerative braking torque and the target hydraulic brake torque matches the required braking torque.

The hydraulic brake control unit 240 controls the pump and the control valve provided in the hydraulic unit 70 based on the set target hydraulic brake torque. Thereby, the hydraulic brake torque of the hydraulic brake 62 is controlled.

[1-4. Operation example of control device]
So far, the configuration example of the control device 100 has been described. Hereinafter, an operation example of the control device 100 will be described.

(1-4-1. Outline)
First, an outline of a control method of the vehicle 1 by the control device 100 will be described with reference to FIGS. FIG. 3 is an explanatory diagram illustrating an operation example of a control device for a vehicle according to a comparative example. 4 and 5 are explanatory diagrams showing an operation example of the control device for a vehicle according to the present embodiment.

An operation example of the vehicle control device according to the comparative example will be described with reference to FIG. The control device for the vehicle according to the comparative example differs from the control device for the vehicle according to the present embodiment in that the engine speed is used as an input parameter when setting the maximum regenerative braking torque tra.

At time t90, when the engine speed reaches the first engine speed na obtained by adding an appropriate offset value to the fuel injection restart speed nb, the control device according to the comparative example starts the braking force replacement control.

After time t90, the control device according to the comparative example sets the value of the maximum regenerative braking torque tra using the engine speed as an input parameter. For example, the value of the maximum regenerative braking torque tra is set by multiplying the engine speed by a predetermined coefficient.

Here, in general, when the vehicle 1 is decelerated, the engine speed does not decrease linearly but decreases with slight vertical fluctuation. Therefore, the maximum regenerative braking torque tra set using the engine speed as an input parameter decreases with vertical fluctuation.

Further, the control device according to the comparative example compares the required braking torque tre calculated based on the operation amount of the brake pedal acquired from the brake sensor 81 with the maximum regenerative braking torque tra, and determines the smaller value. Is set as the target regenerative braking torque.

場合 When the maximum regenerative braking torque tra is lower than the required braking torque tre, the target regenerative braking torque matches the maximum regenerative braking torque tra. In this case, the target regenerative braking torque decreases with vertical fluctuation. Thereby, regenerative braking torque trb actually generated by motor generator 30 decreases with vertical fluctuation.

In the example shown in FIG. 3, since the required braking torque tre is constant after time t90, when the target regenerative braking torque decreases with vertical fluctuation, the target hydraulic brake torque increases with vertical fluctuation.

Here, the regenerative braking torque trb actually generated by the motor generator 30 is generated by the inverter 34 controlling the motor generator 30 according to the target regenerative braking torque set by the regenerative braking torque control unit 230. That is, the regenerative braking torque trb is controlled by the electric signal.

On the other hand, the hydraulic brake torque trc actually generated by the hydraulic brake 62 is driven by a pump provided in the hydraulic unit 70 in accordance with the target hydraulic brake torque set by the hydraulic brake control unit 240, and the control valve is connected to the hydraulic passage. It is generated by performing the opening / closing operation. That is, the hydraulic brake torque trc is physically controlled.

Therefore, the responsiveness and followability of the hydraulic brake torque trc are inferior to the regenerative braking torque trb. That is, the total torque trd of the regenerative braking torque trb and the hydraulic brake torque trc may not coincide with the required braking torque tr and may be accompanied by vertical fluctuations. Therefore, the control device according to the comparative example may cause vibration of the vehicle 1 when replacing the braking force.

Next, an operation example of the vehicle control device according to the present embodiment will be described with reference to FIG. FIG. 4 is an operation example of the control device 100 when the vehicle 1 is traveling on a flat road.

At time t10, when the engine rotation speed reaches the first rotation speed na obtained by adding an appropriate offset rotation speed to the fuel injection restart rotation speed nb, the control start determination unit 210 determines to start the braking force replacement control.

At time t10, the maximum regenerative braking torque setting unit 220 sets the regenerative braking torque trb at that time as an initial value of the maximum regenerative braking torque tra. Then, the maximum regenerative braking torque setting unit 220 monotonically decreases the maximum regenerative braking torque with the passage of time. In the example shown in FIG. 4, the maximum regenerative braking torque decreases linearly.

By the way, as described above, the followability of the hydraulic brake torque trc is inferior to the regenerative braking torque trb. That is, when the regenerative braking torque trb suddenly decreases, the increase in the hydraulic brake torque trc may not catch up.

Therefore, the angle of the gradient at the time of reducing the maximum regenerative braking torque tra is such that the hydraulic brake 62 has a target hydraulic brake torque that increases in contradiction with the target regenerative braking torque that decreases as the maximum regenerative braking torque tra decreases. It is preferable that the angle be determined so as to be able to follow.

At the same time, the gradient when the maximum regenerative braking torque tra decreases is such that the maximum regenerative braking torque tra becomes zero before the engine speed reaches the idling speed nd while the vehicle 1 is traveling under the predetermined conditions. May be determined so that The predetermined condition may be, for example, a state where the vehicle 1 is traveling on a flat road, a state where the clutch mechanism 40 is engaged, and a state where the accelerator pedal and the brake pedal are released.

For example, when the gradient is linear, the gradient angle may be set so that the rate of decrease in the maximum regenerative braking torque tra is -250 Nm / sec.

において After time t10, the regenerative braking torque control unit 230 calculates the required braking torque tre based on the operation amount of the brake pedal acquired from the brake sensor 81 and the like. Further, the regenerative braking torque control unit 230 compares the required braking torque tre with the maximum regenerative braking torque tra, and sets a smaller value as the target regenerative braking torque.

では In the example shown in FIG. 4, after time t10, the maximum regenerative braking torque tra is smaller than the required braking torque tre. For this reason, the value of the target regenerative braking torque matches the value of the maximum regenerative braking torque tra, and decreases linearly with time. Accordingly, the regenerative braking torque trb decreases linearly with time.

において After time t10, the hydraulic brake control unit 240 sets the difference between the required braking torque tre and the target regenerative braking torque as the target hydraulic brake torque for causing the hydraulic brake 62 to generate.

In the example shown in FIG. 4, since the required braking torque tre is constant, if the target regenerative braking torque decreases linearly with time, the target hydraulic brake torque increases linearly with time. Accordingly, the hydraulic brake torque trc increases linearly with the passage of time.

Thereafter, at time t11 before the time t13 when the engine speed reaches the idling speed nd, the regenerative braking torque trb becomes 0, and the braking force replacement control ends.

As described above, in the present embodiment, the regenerative braking torque trb decreases linearly with the passage of time. The hydraulic brake torque trc increases linearly with time so as to compensate for the difference between the required braking torque tr and the regenerative braking torque trb.

Accordingly, the total torque trd of the regenerative braking torque trb and the hydraulic braking torque trc becomes constant. That is, the vehicle control device 100 according to the present embodiment can smoothly replace the braking torque of the vehicle 1 from the regenerative braking torque trb to the hydraulic brake torque trc when the vehicle decelerates.

In addition, in the example shown in FIG. 4, the regenerative braking torque trb is 0 before the time t13 when the engine speed reaches the idling speed nd. That is, the vehicle control device 100 according to the present embodiment can improve the certainty of preventing the engine stall.

Next, with reference to FIG. 5, a case where the regenerative braking torque may not become 0 before the engine speed reaches the idling speed will be described. FIG. 5 is an operation example of the control device 100 in the vehicle 1 traveling on an uphill. In the operation example of the control device 100 shown in FIG. 5, the decreasing speed of the engine speed is faster than that in FIG.

In the example shown in FIG. 5, the operation of the control device 100 of the vehicle until the time t12 when the engine speed reaches the second speed nc is the same as the operation shown in FIG.

In the example shown in FIG. 5, the maximum regenerative braking torque tra is not 0 at time t12 when the engine speed reaches the second speed nc. In such a situation, when the angle of the gradient of the decreasing maximum regenerative braking torque tra is not changed, the regenerative braking torque trb may not become zero before the time t13 when the engine speed reaches the idling speed nd. is there.

において At time t12, the maximum regenerative braking torque setting unit 220 changes the gradient of the decreasing maximum regenerative braking torque tra such that the angle of the gradient increases.

At this time, the maximum regenerative braking torque setting unit 220 may change the gradient such that the changed maximum regenerative braking torque tra decreases linearly with the passage of time. For example, the angle of the gradient may be set so that the rate of decrease of the maximum regenerative braking torque tra is −500 N · m / sec.

As described above, in the example shown in FIG. 5, when there is a possibility that the regenerative braking torque does not become 0 before the engine rotational speed reaches the idling rotational speed, the angle of the decreasing gradient of the maximum regenerative braking torque tra is halfway. growing.

Accordingly, the regenerative braking torque trb becomes zero before time t13 when the engine speed reaches the idling speed nd. Therefore, the control device 100 for a vehicle according to the present embodiment can further improve the reliability of preventing the engine stall.

(1-4-2. Flowchart)
Next, a control method of the vehicle 1 by the control device 100 will be described with reference to FIG. FIG. 6 is a flowchart illustrating an operation example of the control device 100 of the vehicle 1 according to the present embodiment.

First, the control start determination unit 210 determines whether the engine speed acquired from the engine speed sensor 87 has reached the above-described first speed during vehicle deceleration (step S11).

When the engine speed has not reached the first speed (S11 / no), the control start determination unit 210 determines that the braking force replacement control is not to be started, and the engine speed has reached the first speed. The determination in step S11 is repeated until the determination is made.

On the other hand, when the engine speed has reached the first speed (S11 / yes), the control start determination unit 210 determines to start the braking force replacement control.

When the control start determination unit 210 determines that the braking force replacement control is to be started, the maximum regenerative braking torque setting unit 220 decreases the maximum regenerative braking torque over time as described above (step S13). The maximum regenerative braking torque setting unit 220 linearly reduces the maximum regenerative braking torque, for example.

Next, the regenerative braking torque controller 230 sets a target regenerative braking torque based on the maximum regenerative braking torque and information from various sensors. Further, the hydraulic brake control unit 240 sets a target hydraulic brake torque based on the required braking torque and the target regenerative braking torque (Step S15).

目標 If the target regenerative braking torque exceeds the maximum regenerative braking torque, the target regenerative braking torque decreases linearly. Accordingly, the target hydraulic brake torque obtained by subtracting the target regenerative braking torque from the required braking torque increases linearly.

Next, the maximum regenerative braking torque setting unit 220 determines whether or not the engine speed has reached the above-described second speed (step S17).

If the engine speed has not reached the second speed (S17 / no), the maximum regenerative braking torque setting unit 220 repeats the determination in step S17 until the engine speed reaches the second speed.

On the other hand, when the engine speed has reached the second speed (S17 / yes), the maximum regenerative braking torque setting unit 220 determines whether or not the maximum regenerative braking torque is 0 (step S19). ).

If the maximum regenerative braking torque is not 0 (S19 / no), the maximum regenerative braking torque setting unit 220 increases the angle of the gradient of the decreasing maximum regenerative braking torque. Then, when the regenerative braking torque becomes 0 and the replacement of the braking force ends, the vehicle control device 100 according to the present embodiment ends the braking force replacement control.

On the other hand, when the maximum regenerative braking torque is 0 (S19 / yes), the vehicle control device 100 according to the present embodiment ends the braking force replacement control as it is.

The clutch mechanism 40 may be disconnected by the driver during the braking force replacement control. In this case, since the connection of the drive wheel 60 to the engine 20 is released, the regenerative control of the motor generator 30 can no longer be performed.

Therefore, the regenerative braking torque is quickly reduced to zero, and the required braking torque of the vehicle 1 becomes the target hydraulic brake torque as it is. Therefore, when the driver disengages the clutch mechanism 40 during the braking force replacement control, the control device 100 may end the braking force replacement control at that time.

[1-5. Effect of control device]
Subsequently, effects of the control device 100 according to the present embodiment will be described.

According to the vehicle control device 100 according to the present embodiment, the target regenerative braking torque monotonously decreases with the passage of time during the braking force replacement control. Further, the target hydraulic brake torque compensates for a difference between the required braking torque and the target regenerative braking torque.

Accordingly, the vehicle control device 100 according to the present embodiment can smoothly replace the braking torque of the vehicle from the regenerative braking torque to the hydraulic braking torque when the vehicle decelerates. As a result, vibration of the vehicle 1 can be suppressed.

In the vehicle control device 100 according to the present embodiment, the target regenerative braking torque decreases linearly with time. For this reason, the target hydraulic brake torque also increases relatively monotonously, and the effect of suppressing the vibration of the vehicle 1 can be improved.

In addition, in the vehicle control device 100 according to the present embodiment, the target regenerative braking torque is controlled such that the target engine speed becomes zero before the engine speed reaches the idling speed. Therefore, the control device 100 of the vehicle according to the present embodiment can improve the reliability of preventing the engine stall during the vehicle deceleration.

In the vehicle control device 100 according to the present embodiment, if the regenerative braking torque does not become 0 before the engine speed reaches the idling speed, the angle of the gradient of the reduced maximum regenerative braking torque is halfway. Is changed to be larger.

Thereby, the certainty that the regenerative braking torque becomes zero before the engine speed reaches the idling speed is further improved. Therefore, the control device 100 for a vehicle according to the present embodiment can further improve the reliability of preventing the engine stall.

<2. Second Embodiment>
A vehicle control device according to a second embodiment of the present invention will be described. The control device for a vehicle according to the present embodiment is different from the first embodiment in that the vehicle speed is used as an engine speed index for determining whether to start the braking force replacement control. Hereinafter, points different from the control device of the vehicle of the first embodiment will be mainly described.

[2-1. Overall configuration of vehicle]
First, an example of the overall configuration of a vehicle to which the vehicle control device according to the present embodiment can be applied will be described with reference to FIG. FIG. 7 is a schematic diagram showing the vehicle 2 including the vehicle control device 300. Hereinafter, an example of the overall configuration of the vehicle 2 will be described separately for the power unit 11 and the control device 300.

(2-1-1. Power unit)
The power unit 11 of the vehicle 2 includes an automatic transmission having a continuously variable transmission mechanism 51 (hereinafter, also referred to as “CVT”) instead of the stepped transmission mechanism. The continuously variable transmission mechanism 51 has a primary pulley and a secondary pulley, and the primary pulley is connected to the motor generator 30 via the clutch mechanism 41. The secondary pulley is connected to the driving wheel 60 via a differential mechanism.

When the continuously variable transmission mechanism 51 is provided, the engine speed can be kept constant by changing the ratio (pulley ratio) between the pulley diameter of the primary pulley and the pulley diameter of the secondary pulley when the vehicle 2 is decelerated. For this reason, in the vehicle 2 provided with the continuously variable transmission mechanism 51, control for keeping the engine speed at or above the fuel injection restart speed during deceleration may be performed.

In such a case, it is difficult to determine whether to start the braking force replacement control based on whether or not the engine speed has decreased and reached the first speed. For this reason, the control device 300 according to the present embodiment uses the vehicle speed as an engine speed index for determining whether to start the braking force replacement control.

Note that when the continuously variable transmission mechanism 51 cannot maintain a constant engine speed during the deceleration of the vehicle 2 (that is, when the pulley ratio of the continuously variable transmission mechanism 51 reaches the maximum value), the engine rotation is stopped. The number decreases with decreasing vehicle speed.

The clutch mechanism 41 can switch the engagement state between the motor generator 30 and the continuously variable transmission mechanism 51. The clutch mechanism 41 corresponds to a lock-up clutch of the torque converter. The configuration of the power unit 11 other than the continuously variable transmission mechanism 51 and the clutch mechanism 41 is the same as that of the vehicle 1 described above.

(2-1-2. Control device)
The control device 300 of the vehicle 2 includes an engine controller 310 and a brake controller 320. A brake sensor 81, an accelerator sensor 83, an engine speed sensor 87, and a vehicle speed sensor 89 are connected to the engine controller 310.

The vehicle speed sensor 89 detects the vehicle speed of the vehicle 2. The engine controller 310 and the brake controller 320 correspond to the engine controller 110 and the brake controller 120 in the first embodiment.

The basic operation of the braking force replacement control by the control device 300 is the same as that of the above-described first embodiment, except that the engine speed index for determining whether to start the braking force replacement control is the vehicle speed. .

However, in the vehicle 2 including the automatic transmission having the continuously variable transmission mechanism 51, the vehicle speed may decrease, and it may be difficult to maintain the engine speed at or above the fuel injection restart speed. For this reason, the control device 300 according to the present embodiment differs from the first embodiment in that the control device 300 ends the replacement of the regenerative braking torque with the hydraulic brake torque before the fuel injection to the engine 20 is restarted. different.

In the vehicle 2 including the automatic transmission having the continuously variable transmission mechanism 51, when the vehicle speed decreases and it becomes difficult to keep the engine speed constant, fuel injection is restarted to prevent engine stall. At this time, control may be performed to release the engaged state of the clutch mechanism 41 so that the output torque of the engine 20 is not transmitted to the drive wheels 60. When the clutch mechanism 41 is released from the engaged state, for example, a clutch release flag is generated by a transmission controller (not shown).

In this case, since the regenerative efficiency utilizing the rotational energy of the drive wheels 60 is reduced, the brake controller 320 immediately sets the regenerative braking torque to zero, and sets the required braking torque of the vehicle 2 as the target hydraulic brake torque as it is.

If the regenerative braking torque is not 0 when the clutch mechanism 41 is released from the engaged state, the regenerative braking torque may be rapidly switched to the hydraulic brake torque. As described above, the responsiveness and followability of the hydraulic brake torque are inferior to the regenerative braking torque. Therefore, the braking force of the vehicle 2 may fluctuate, which may affect drivability.

Therefore, in the present embodiment, the brake controller 320 performs control so that the replacement of the regenerative braking torque with the hydraulic brake torque is completed before the engine speed reaches the fuel injection restart speed. Hereinafter, a specific example of the control device 300 capable of executing such braking force replacement control will be described.

[2-3. Specific example of control device]
A specific example of the vehicle control device 300 according to the present embodiment will be described. FIG. 8 is an explanatory diagram illustrating a functional configuration of a portion related to the braking force replacement control in the control device 300 including the engine controller 310 and the brake controller 320 illustrated in FIG.

The control device 300 includes a control start determination unit 410, a maximum regenerative braking torque setting unit 420, a regenerative braking torque control unit 430, and a hydraulic brake control unit 440. Control device 300 acquires signals output from brake sensor 81, accelerator sensor 83, engine speed sensor 87, and vehicle speed sensor 89, and information on the clutch disengagement state.

うち The regenerative braking torque controller 430 and the hydraulic brake controller 440 are configured similarly to the regenerative braking torque controller 230 and the hydraulic brake controller 240 of the control device 100 according to the first embodiment.

(Control start determination unit)
For example, the engine controller 310 functions as the control start determination unit 410. In the present embodiment, the control start determination unit 410 determines whether or not the vehicle speed acquired from the vehicle speed sensor 89 has reached a preset first speed during vehicle deceleration. When the vehicle speed has reached the first speed, the control start determination unit 410 determines to start the braking force replacement control from the regenerative braking torque to the hydraulic brake torque.

As described above, in the present embodiment, it is preferable that the braking force replacement process be completed before resuming fuel injection to the engine 20. In the case of the present embodiment in which the engine speed is maintained equal to or higher than the fuel injection restart speed by controlling the continuously variable transmission mechanism 51, the first speed is maintained at a constant engine speed even by adjusting the pulley ratio. The vehicle speed at the time when the engine speed decreases to reach the fuel injection restart speed without performing the engine speed (hereinafter, also referred to as “vehicle speed at the time of restarting fuel injection”) is a speed obtained by adding an appropriate offset value. Good.

However, if the first speed is excessively higher than the vehicle speed at the time of resuming fuel injection, some of the regenerative braking torque is replaced with the hydraulic brake torque, despite the fact that fuel efficiency is not deteriorated, and Efficiency decreases. Therefore, it is preferable that the offset value is determined in consideration of the regeneration efficiency.

(Maximum regenerative braking torque setting section)
For example, the engine controller 310 functions as the maximum regenerative braking torque setting unit 420. The maximum regenerative braking torque setting unit 420 sets the maximum regenerative braking torque similarly to the above-described maximum regenerative braking torque setting unit 220.

As described above, in the present embodiment, it is preferable that the braking force replacement process be completed before the fuel injection is restarted. Therefore, when it is determined that the maximum regenerative braking torque does not become 0 before the vehicle speed reaches the vehicle speed at the time of resuming fuel injection, the maximum regenerative braking torque setting unit 420 increases the gradient for decreasing the maximum regenerative braking torque. Then, the maximum regenerative braking torque may be immediately reduced to zero.

For example, when the maximum regenerative braking torque is not 0 when the vehicle speed of the vehicle 2 reaches the second speed set in advance, the maximum regenerative braking torque setting unit 420 increases the angle of the gradient. The reduction rate of the maximum regenerative braking torque may be increased. The second speed may be, for example, a speed obtained by adding an appropriate offset value to the vehicle speed at the time of restarting fuel injection.

[2-4. Operation example of control device]
(2-4-1. Outline)
With reference to FIGS. 9 and 10, an outline of a method of controlling vehicle 2 by control device 300 will be described. 9 and 10 are explanatory diagrams showing an operation example of the control device for a vehicle according to the present embodiment.

FIG. 9 is an operation example of the control device 300 when the vehicle 2 is traveling on a flat road.
At time t30, when the vehicle speed reaches the above-described first speed va, the control start determination unit 410 determines to start the braking force replacement control from the regenerative braking torque trb to the hydraulic brake torque trc.

において After time t30, the maximum regenerative braking torque setting unit 420 sets the regenerative braking torque trb at time t30 as an initial value of the maximum regenerative braking torque tra, and decreases the maximum regenerative braking torque tra over time. In the example shown in FIG. 9, the maximum regenerative braking torque decreases linearly.

It is preferable that the gradient at the time of reducing the maximum regenerative braking torque tra be set within a range in which the hydraulic brake 62 can follow the target hydraulic brake torque, as in the first embodiment.

At the same time, the gradient at the time of decreasing the maximum regenerative braking torque tra is such that the maximum regenerative braking torque tra before the engine speed reaches the fuel injection restart speed nb while the vehicle 2 is traveling under the predetermined conditions. May be set to 0. The predetermined condition may be the same as the condition in the first embodiment.

において After time t30, the value of the target regenerative braking torque matches the value of the maximum regenerative braking torque tra, and decreases linearly with time. Accordingly, the target hydraulic brake torque increases linearly with the passage of time. Therefore, the regenerative braking torque trb decreases linearly with the passage of time, and the hydraulic brake torque trc increases linearly with the passage of time.

Thereafter, at time t31 before the time t33 when the engine speed reaches the fuel injection restart speed nb, the regenerative braking torque trb becomes 0, and the braking force replacement control ends.

Accordingly, the total torque trd of the regenerative braking torque trb and the hydraulic braking torque trc becomes constant. That is, the vehicle control device 300 according to the present embodiment can smoothly replace the braking torque of the vehicle 2 from the regenerative braking torque trb to the hydraulic brake torque trc during vehicle deceleration.

In addition, in the example shown in FIG. 9, the regenerative braking torque trb is 0 before the time t33 when the engine speed reaches the fuel injection restart speed nb. Therefore, the control device 300 of the vehicle according to the present embodiment can improve the certainty of preventing deterioration of fuel efficiency and drivability.

Next, a case where the regenerative braking torque may not become 0 before the engine speed reaches the fuel injection restart speed will be described with reference to FIG. FIG. 10 is an operation example of the control device 300 in the vehicle 2 traveling on an uphill. In the operation example of the control device 300 shown in FIG. 10, the decrease speed of the vehicle speed is faster than that in FIG. That is, the time required for the engine speed to reach the fuel injection restart speed is shorter than that in FIG.

In the example shown in FIG. 10, the operation of the control device 300 of the vehicle until time t32 when the vehicle speed reaches the above-described second speed vb is the same as the above-described operation shown in FIG.

In the example shown in FIG. 10, the maximum regenerative braking torque tra is not 0 at time t32 when the vehicle speed of the vehicle 2 reaches the second speed vb. In such a situation, when the angle of the gradient of the decreasing maximum regenerative braking torque tra is not changed, the regenerative braking torque trb may not become 0 before the time t33 when the engine speed reaches the fuel injection restart speed nb. There is.

Therefore, at time t32, the maximum regenerative braking torque setting unit 420 increases the gradient angle of the maximum regenerative braking torque tra that decreases as described above.

As described above, in the example illustrated in FIG. 10, when the regenerative braking torque may not become 0 before the engine speed reaches the fuel injection restart speed, the angle of the gradient that reduces the maximum regenerative braking torque tra On the way.

Accordingly, the regenerative braking torque trb becomes zero before the time t33 when the engine speed reaches the fuel injection restart speed nb. Therefore, the control device 300 of the vehicle according to the present embodiment can further improve the certainty of suppressing the deterioration of the fuel efficiency and the decrease of the drivability.

(2-4-2. Flowchart)
Next, a control method of the vehicle 2 by the control device 300 will be described with reference to FIG. FIG. 11 is a flowchart illustrating an operation example of the vehicle control device according to the present embodiment.

The control start determination unit 410 determines whether the vehicle speed acquired from the vehicle speed sensor 89 has reached the above-described first speed during vehicle deceleration (step S31).

When the vehicle speed has not reached the first speed (S31 / no), the control start determination unit 410 determines that the braking force replacement control is not to be started, and determines in step S31 until the vehicle speed reaches the first speed. repeat. On the other hand, when the vehicle speed has reached the first speed (S31 / yes), the control start determination unit 410 determines to start the braking force replacement control.

When the control start determination unit 410 determines that the braking force replacement control is to be started, the maximum regenerative braking torque setting unit 420 decreases the maximum regenerative braking torque with the passage of time as described above (step S33). The maximum regenerative braking torque setting unit 420 linearly reduces the maximum regenerative braking torque, for example.

Next, the regenerative braking torque control unit 430 sets the target regenerative braking torque based on the maximum regenerative braking torque that decreases over time and information from various sensors. Further, the hydraulic brake control unit 440 sets the target hydraulic brake torque based on the required braking torque and the target regenerative braking torque (Step S35).

Next, the maximum regenerative braking torque setting unit 420 determines whether or not the vehicle speed has reached the above-described second speed (Step S37).

If the vehicle speed has not reached the second speed (S37 / no), the maximum regenerative braking torque setting unit 420 repeats the determination in step S37 until the vehicle speed reaches the second speed. On the other hand, when the vehicle speed has reached the second speed (S37 / yes), the maximum regenerative braking torque setting unit 420 determines whether the maximum regenerative braking torque is 0 (step S39).

If the maximum regenerative braking torque is not 0 (S39 / no), the maximum regenerative braking torque setting unit 420 increases the angle of the decreasing gradient of the maximum regenerative braking torque. Then, when the regenerative braking torque becomes 0 and the replacement of the braking force ends, the vehicle control device 300 according to the present embodiment ends the braking force replacement control.

On the other hand, when the maximum regenerative braking torque is 0 (S39 / yes), the vehicle control device 300 according to the present embodiment ends the braking force replacement control as it is.

In the above description, an example in which the vehicle speed is used as the engine speed index for determining whether or not to start the braking force replacement control in the vehicle 2 including the automatic transmission having the continuously variable transmission mechanism 51 has been described. The form is not limited to such an example.

For example, the vehicle speed may be used as an engine speed index for determining whether or not to start the braking force replacement control in the vehicle 1 including the stepped transmission mechanism 50 as exemplified in the first embodiment.

[2-5. Effect of control device]
Effects of the control device 300 according to the present embodiment will be described.

In the vehicle control device 300 according to the present embodiment, the vehicle speed is used as an engine speed index for determining whether to start the braking force replacement control. For this reason, the braking force replacement control can be applied to the vehicle 2 in which the control for maintaining the engine rotation speed equal to or higher than the fuel injection restart rotation speed is performed, similar to the control device 100 according to the first embodiment. The effect of can be obtained.

In addition, in the vehicle control device 300 according to the present embodiment, the regenerative braking torque is controlled to become 0 before the engine speed reaches the fuel injection restart speed. Therefore, the control device 300 of the vehicle according to the present embodiment can improve the certainty of suppressing the deterioration of the fuel efficiency and the decrease of the drivability when the vehicle is decelerated.

<3. Conclusion>
As described above, in the vehicle control device according to the embodiment of the present invention, when the regenerative braking torque is generated during the fuel cut control, the engine speed index correlated with the engine speed satisfies a predetermined condition. Then, the target regenerative braking torque is reduced at a predetermined gradient, and the difference between the required braking torque of the vehicle and the target regenerative braking torque is set as the target hydraulic brake torque.

Thereby, the regenerative braking torque does not decrease with vertical fluctuation, and the regenerative braking torque can be smoothly replaced with the hydraulic brake torque.

Although the preferred embodiments of the present invention have been described above in detail with reference to the accompanying drawings, the present invention is not limited to such examples. It is obvious that those skilled in the art to which the present invention pertains can conceive various changes or modifications within the scope of the technical idea described in the claims. It is understood that these also belong to the technical scope of the present invention. Further, a mode in which the above embodiments are combined with each other naturally belongs to the technical scope of the present invention.

For example, in the above embodiment, the vehicle control device includes two controllers, but the present invention is not limited to this example. Some or all of the functions of the above controller may be integrated into one controller, or may be further divided into a plurality of controllers. Further, a higher-level controller that controls the two controllers in cooperation with each other may be provided.

Also, for example, in the above embodiment, the motor generator has functions as a starter and a braking device, but the present invention is not limited to such an example. The motor generator may further have a function as a power source.

1, 2, ... vehicle, 10, 11 ... power unit, 20 ... engine, 30 ... motor generator, 32 ... battery, 34 ... inverter, 40, 41 ... clutch mechanism, 50: stepped transmission mechanism, 51: stepless transmission mechanism, 60: drive wheel, 62: hydraulic brake, 70: hydraulic unit, 81: brake sensor, 83 ... Accelerator sensor, 85: clutch sensor, 87: engine speed sensor, 89: vehicle speed sensor, 100, 300: control device, 110, 310: engine controller, 120, 320 Brake controllers, 210, 410: control start determination unit, 220, 420: maximum regenerative braking torque setting unit, 230, 430: regenerative braking torque control unit, 240, 4 0 ... hydraulic brake control unit

Claims

It is mounted on a vehicle (1) including an engine (20) and a motor generator (30) connected in series, and a hydraulic brake (62) operated by hydraulic pressure. A vehicle control device (100) for controlling a hydraulic brake torque generated by the hydraulic brake (62),
In a state where the regenerative braking torque is generated during the fuel cut control for stopping the injection of fuel to the engine (20), an engine speed index correlated with the speed of the engine (20) satisfies a predetermined condition. A regenerative braking torque control unit (230) that reduces the target regenerative braking torque at a predetermined gradient when:
A vehicle control comprising: a hydraulic brake control unit (240) that sets a difference between a required braking torque requested by a driver of the vehicle (1) and the target regenerative braking torque as a target hydraulic brake torque. Apparatus (100).
The predetermined gradient is
While the vehicle (1) is traveling under predetermined conditions, the value of the target regenerative braking torque is set to 0 before the rotation speed of the engine (20) reaches the idling rotation speed of the vehicle (1). The vehicle control device (100) according to claim 1, wherein the vehicle control device (100) is set to:
The angle of the predetermined gradient is
The control device (100) for a vehicle according to claim 1, wherein the hydraulic brake is set within a range in which the hydraulic brake can follow the target hydraulic brake torque.
The engine speed index is:
The control device (100) for a vehicle according to any one of claims 1 to 3, wherein the control device is a rotation speed of the engine (20).
The regenerative braking torque control unit (230) includes:
The vehicle control device according to claim 4, wherein the target regenerative braking torque is reduced at a predetermined gradient when the rotation speed of the engine (20) reaches a preset reference rotation speed. 100).
The reference rotation speed is
The vehicle control device according to claim 5, wherein the rotation speed is obtained by adding a first offset rotation speed to a fuel injection restart rotation speed serving as a reference for restarting fuel injection to the engine (20). 100).
The regenerative braking torque control unit (230) includes:
When it is determined that the value of the target regenerative braking torque does not become 0 before the rotation speed of the engine (20) reaches the idling rotation speed, the angle of the predetermined gradient is increased. A control device (100) for a vehicle according to any one of the preceding claims.
The regenerative braking torque control unit (230) includes:
When the value of the target regenerative braking torque is not 0 when the number of revolutions of the engine (20) becomes the number of revolutions obtained by adding the second offset number of revolutions to the idling number of revolutions, The control device (100) of a vehicle according to claim 7, wherein the angle is increased.
The vehicle control device (300) according to any one of claims 1 to 3, wherein the engine speed index is a vehicle speed of the vehicle (2).
The regenerative braking torque control unit (430) includes:
The vehicle control device (300) according to claim 9, wherein the target regenerative braking torque is reduced at a predetermined gradient when the vehicle speed reaches a first speed set in advance.
The vehicle (2) is
Having a continuously variable transmission mechanism (51),
The predetermined gradient is
While the vehicle (2) is traveling under a predetermined condition, the rotation speed of the engine (20) before the rotation speed of the engine (20) reaches a fuel injection restart rotation speed serving as a reference for restarting fuel injection to the engine (20). The control device (300) for a vehicle according to claim 9 or 10, wherein the value of the target regenerative braking torque is set to 0.
The regenerative braking torque control unit (430) includes:
The vehicle speed is a speed obtained by adding an appropriate offset value to the vehicle speed at the time when the rotation speed of the engine (20) reaches a fuel injection restart rotation speed serving as a reference for restarting fuel injection to the engine (20). The control of the vehicle according to any one of claims 9 to 11, wherein when the value of the target regenerative braking torque is not 0, the angle of the predetermined gradient is increased. Apparatus (300).
The control device (300) for a vehicle according to any one of claims 1 to 12, wherein the predetermined slope is linear.