JPH11122712A - Controller for hybrid car - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance acceleration at the time of reacceleration after deceleration. SOLUTION: An engine 3 and a first motor 1 are provided as prime movers for a car. When it is detected that a brake becomes nonoperative from an operating state, when a first clutch 4 which cuts the linkage of the output shaft of the engine 3 to driving wheels 2 selectively is in a disconnected state, a second clutch 7 which disconnects the linkage of a second motor 5 to the output shaft of the engine 3 selectively is connected, and the engine 3 is driven/ rotated by a second motor 5 preparatorily. And at the point of time when an accelerator is operated, fuel is supplied and the engine 3 is caused to operate autonomously. And the first clutch 4 is connected, and the driving wheels 2 are driven/rotated by the engine 3 and the first motor 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a hybrid vehicle having a motor and an engine as a prime mover of a vehicle, and more particularly to improving the acceleration performance when the vehicle is re-accelerated with the engine disconnected during deceleration. Related to the technology.

[0002]

2. Description of the Related Art Various types of prior art related to a hybrid vehicle having a motor and an engine as a prime mover of a vehicle are known.

[0003] In this kind of hybrid vehicle,
The output shaft of each of the engine and the motor is connected to the axle of the drive wheel via a clutch, and controls the connection or disconnection of each clutch so that the vehicle runs by the driving force of one or both of the engine and the motor. Like that. From the viewpoint of improving fuel efficiency, the motor is used as a generator during deceleration to regenerate the kinetic energy of the vehicle.

Japanese Patent Laid-Open No. 3-3192 discloses a hybrid vehicle which is used in an urban area as an electric vehicle and in a suburb as an internal combustion engine type vehicle.
No. 06 is also known. In this case, in an urban area, when the engine is stopped, only the clutch for the motor is connected, and the vehicle is running with the driving force of the motor, the operation of the accelerator is released (off) and the brake is operated ( On) when the clutch on the engine (engine clutch)
And by forcibly driving the engine to rotate using the braking force of the vehicle, it is possible to prevent the engine from being kept in a stopped state for a long period of time.

[0005]

In the prior art in which the engine clutch is engaged during braking to forcibly rotate the engine, the amount of energy regenerated corresponding to the energy consumed as the engine brake is increased. And the inefficiency is reduced.

On the other hand, in order to increase the amount of energy regenerated by the motor, when the engine is disconnected at the time of deceleration (by disengaging the engine clutch) and energy is regenerated by the motor, when re-acceleration is performed after deceleration, (During deceleration and re-acceleration), there is a problem that it takes time until the engine is restarted, and the acceleration performance is poor.

The present invention has been made in view of such problems of the prior art, and it is possible to improve responsiveness and acceleration during deceleration / re-acceleration and to perform highly efficient energy regeneration. It is an object of the present invention to provide a control device for a hybrid vehicle that can be used.

[0008]

According to a first aspect of the present invention, there is provided a hybrid vehicle control apparatus for driving a vehicle, wherein the engine drives a driving wheel of the vehicle and the driving wheel rotates. In a hybrid vehicle including a first motor, a clutch that selectively disconnects a connection between an output shaft of the engine and the drive wheel, a second motor that rotationally drives the output shaft of the engine, and a state of a brake. A brake state detecting means for detecting the clutch, disengaging the clutch when the brake is in an operating state, and rotating the engine by the second motor when it is detected that the brake is changed from an operating state to a non-operating state; And control means for performing first control for driving.

When re-acceleration is performed after deceleration, it is highly probable that re-acceleration is performed by actuating the accelerator after actuating the brake, releasing the brake, and then paying attention to this point. In the control device for a hybrid vehicle according to the first aspect, when the brake is changed from the operation state to the non-operation state, the engine is reserved by the second motor in anticipation that the accelerator will be operated next. The motor is driven to rotate (motoring).

Therefore, when the accelerator is operated later, by supplying fuel to the engine, etc.,
Since the engine has already been rotated by the second motor, it can start up quickly and improve the re-acceleration responsiveness.

Further, the engine is driven to rotate by the second motor when the brake is changed from the operation state to the non-operation state. Therefore, the clutch for the engine is operated during the operation of the brake as in the above-mentioned prior art. Since there is no need to connect and forcibly rotate the engine, the first
When the kinetic energy of the vehicle is regenerated by the motor, the amount of regenerated energy can be increased by an amount corresponding to the energy consumed as the engine brake,
Fuel efficiency can be greatly improved.

In order to achieve the above object, a control apparatus for a hybrid vehicle according to a second aspect of the present invention is the control apparatus for a hybrid vehicle according to the first aspect, wherein vehicle speed detection means for detecting a vehicle speed, and the engine. And a rotation speed detecting means for detecting a rotation speed of the first motor, and an accelerator state detecting means for detecting an accelerator state, wherein the engine has an electronically controlled throttle valve and a fuel injection valve, The control means drives the drive wheel to rotate by the first motor when the accelerator state detection means detects that the accelerator has changed from the non-operation state to the operation state during the execution of the first control. With the clutch in the engaged state, and based on the difference between the required torque of the vehicle and the torque of the first motor, the opening of the throttle valve and the fuel Characterized by further carrying out the second control that controls the amount of fuel injection by events.

In the control apparatus for a hybrid vehicle according to the second aspect, when the accelerator is operated while the first control is being performed, that is, while the engine is being preliminarily rotated by the second motor. In addition, since the engine is operated (started) autonomously, the clutch is connected, and the engine is accelerated by the driving force of both the engine and the first motor, a relatively low-output motor or a small-capacity battery is used. Even when it is used, high acceleration at the time of deceleration and re-acceleration can be maintained.

Prior to the autonomous operation of the engine,
Since the engine is preliminarily driven to rotate by the second motor, a delay in rising at the time of re-acceleration is small, and responsiveness is good. Further, the throttle opening and the fuel injection amount (engine torque) are controlled based on the difference between the required torque required and the torque of the first motor (actual torque, usually the maximum generated torque), that is, Since the portion of the required torque that is insufficient with the torque of the first motor is supplemented with the engine torque, it is possible to use a relatively low-output motor as the first motor while maintaining the acceleration performance. become able to.

In order to achieve the above object, a control apparatus for a hybrid vehicle according to a third aspect is the control apparatus for a hybrid vehicle according to the second aspect, wherein the control means performs the first and second controls. It is determined whether the opening of the throttle valve is a predetermined opening. If it is determined that the opening is smaller than the predetermined opening, the first and second throttle valves are determined.
The control is stopped.

In the control device for a hybrid vehicle according to the third aspect, when the opening of the throttle valve becomes smaller than the predetermined opening, the first control is stopped (disengagement of the second clutch, operation of the second motor). Stop) and the second control are stopped. This is because the required torque is not satisfied when the opening of the throttle valve is the predetermined opening, but when the opening becomes smaller than the predetermined opening. It is because it is possible to judge that the required torque has been satisfied, and if the required torque is satisfied, it is not necessary to perform assistance by the first motor, and it is more efficient to stop such control. is there.

According to a fourth aspect of the present invention, there is provided a hybrid vehicle control apparatus according to the first aspect, further comprising: accelerator state detection means for detecting an accelerator state; Rotation speed detection means for detecting a rotation speed, wherein the control means detects that the accelerator is inactive by the accelerator state detection means during the execution of the first control; When it is determined that the number of revolutions of the engine detected by the means has reached a predetermined value set in advance, the third motor for controlling the second motor to maintain the number of revolutions of the engine at the predetermined value is used. The control is further performed.

The control device for a hybrid vehicle according to the fourth aspect is, for example, a case where the engine is preliminarily rotated by the second motor at the maximum output and the accelerator is not operated thereafter, that is, when the accelerator is not operated. When it is not accelerated, it is inefficient to continue to drive the engine at the maximum output, so the second motor is controlled to limit the engine speed to a predetermined value, Responsiveness during re-acceleration, while reducing power consumption,
This is to maintain acceleration.

According to a fifth aspect of the present invention, there is provided a hybrid vehicle control device according to the first aspect of the present invention, wherein the brake means is not operated by the brake state detection means. If it is detected that the state has changed to the operating state,
The first control is stopped.

In the control device for a hybrid vehicle according to the fifth aspect, when the brake is activated, it is useless to continue the preliminary rotation driving of the engine by the second motor, and the control is stopped. Thus, high efficiency is achieved.

According to a sixth aspect of the present invention, there is provided a hybrid vehicle control apparatus according to the first aspect, wherein the engine has an electronically controlled throttle valve. The control means fully opens the throttle valve when performing the first control.

In the control apparatus for a hybrid vehicle according to the present invention, when the engine is driven to rotate by the second motor, the load is applied when the throttle valve is closed. Because
The rise time of the engine speed can be reduced. Further, when the accelerator is operated later, the air flows smoothly because the throttle valve is already open, so that the fuel supply and the ignition can be started immediately,
Acceleration responsiveness can also be improved.

[0023]

According to the control apparatus for a hybrid vehicle according to the first aspect, the responsiveness is improved when re-acceleration is performed after deceleration.
There is an effect that acceleration can be improved. In addition, when the energy is regenerated by the motor, the amount of the energy regenerated can be increased as compared with the conventional case, and the fuel efficiency can be greatly improved.

According to the control apparatus for a hybrid vehicle of the second aspect, in addition to the effect of the first aspect,
A relatively small-sized, low-output motor or a small-capacity battery can be adopted as the motor (first motor) for rotating the driving wheels while maintaining the acceleration performance during deceleration and re-acceleration. As a result, the size and weight can be reduced, and the cost can be reduced.

According to the control device for a hybrid vehicle of the third aspect, in addition to the effect of the second aspect,
When the throttle opening is no longer fully open, control is stopped because it is determined that the required torque has been satisfied,
There is an effect that high control efficiency can be achieved.

According to the control device for a hybrid vehicle of the fourth aspect, in addition to the effect of the first aspect,
There is an effect that the responsiveness and acceleration at the time of re-acceleration can be maintained to some extent while suppressing the power consumption of the second motor when the preliminary rotation drive of the engine is performed by the second motor.

According to the control apparatus for a hybrid vehicle of the fifth aspect, in addition to the effect of the first aspect,
There is an effect that it is possible to prevent a decrease in efficiency when re-acceleration is not performed after deceleration.

According to the control apparatus for a hybrid vehicle of the sixth aspect, in addition to the effect of the first aspect,
With respect to the rotation drive of the engine by the second motor, the load can be reduced, the rise time of the engine speed can be reduced, and the acceleration response at the time of re-acceleration can be further improved. is there.

[0029]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a main configuration of a hybrid vehicle according to an embodiment of the present invention, and FIG. 2 is a diagram showing input and output of various signals of a control unit of the embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a first motor (electric motor) used for driving the vehicle and regenerating energy.
The output shaft of the first motor 1 is connected to the axle of the drive wheel 2 via a differential 9.

Reference numeral 3 denotes an engine having an electronically controlled throttle valve and a fuel injection valve. The output shaft (crankshaft) of the engine 3 has a torque converter 11 and a continuously variable transmission 10.
(CVT) and is connected to the output shaft of the first motor 1. The output shaft of the engine 3 and the input shaft of the continuously variable transmission 10 are connected via a first clutch 4 so that these can be selectively connected or disconnected.

Reference numeral 5 denotes a second motor (electric motor) for driving the auxiliary machine 6 such as an air conditioner and rotating the engine 3. The output shaft of the second motor 5 is connected to the output shaft (crankshaft) of the engine via a speed reducer. The output shaft of the second motor 5 and the input shaft of the speed reducer are connected via a second clutch 7, so that the connection between them can be selectively connected or disconnected.

Although not shown, the hybrid vehicle has an engine speed detecting means for detecting the speed of the engine 3, a first motor speed detecting means for detecting the speed of the first motor 1, Second motor rotation speed detection means for detecting the rotation speed of the second motor 5, brake state detection means (brake sensor) for detecting on (operation) or off (non-operation) of the brake, and an accelerator for detecting the operation state of the accelerator State detection means (accelerator sensor), vehicle speed detection means for detecting the speed of the vehicle, first clutch state detection means for detecting on (connection) or off (disconnection) of first clutch 4, and on (connection) of second clutch 7 ) Or off (cut)
The second clutch state detecting means for detecting the

As shown in FIG. 2, signals from these means are input to a control means 8 including a vehicle running state determining means and a command mode determining means. That is, the engine speed Ne by the engine speed detecting means, the first motor speed Nma by the first motor speed detecting means, and the second motor speed Nm by the second motor speed detecting means.
b, brake sensor signal B by the brake state detecting means
R, accelerator sensor signal A by accelerator state detection means
C, the vehicle speed VSP by the vehicle speed detecting means, the first clutch connecting / disconnecting signal CL1 by the first clutch state detecting means, and the second clutch connecting / disconnecting signal CL2 by the second clutch state detecting means.
Are respectively input to the control means 8.

The control means 8 controls the first clutch 4, the second clutch 7, the first motor 1, the second motor 5, and the engine (throttle valve or fuel injection valve) based on these signals and other signals and data. Etc.) 3 to output command signals and control them. Here, the operation of the first clutch 4 will be briefly described. In order to increase the regenerative energy by the first motor 1 during deceleration of the vehicle, the accelerator pedal is turned off.
When the brake pedal is depressed and the brake pedal is depressed, the first clutch 4 is disengaged, and the engine 3 is disconnected from the wheels. On the other hand, when the brake pedal is turned off, there is a high probability that the vehicle will re-accelerate, so the first clutch 4 is connected before the accelerator pedal is depressed. Specifically, it operates according to the flowchart of FIG. 3 described below.

FIG. 3 is a flowchart showing processing by the control means according to the embodiment of the present invention. First, the control unit 8 reads a signal from each unit (each unit) (S1). That is,
The engine speed Ne, the first motor speed Nma, the second motor speed Nmb, the brake sensor signal BR, the accelerator sensor signal AC, the vehicle speed signal VSP, the first clutch connection / disconnection signal CL1, and the second clutch connection / disconnection signal CL2 are read. .

Next, the output (required torque) of the first motor 1 is calculated according to the detected operating state (S2), and the output is commanded to the first motor 1 (S3). It is determined whether the first clutch connection / disconnection signal CL1 = OFF (the engine is disconnected) (S4), and the first clutch connection / disconnection signal C is determined.
When L1 = OFF (in the case of Yes), it is determined whether or not the brake sensor signal BR = 0 (brake is not operated) (S5).

In S5, the brake sensor signal BR =
If it is 0 (Yes), it is determined whether or not the previous (immediately) brake sensor signal BRO = 0 (brake not operating) (S6), and the previous brake sensor signal BRO = 1.
If (brake operation) (No), the control flag FMG is set to 1 (S7). Thereafter, control is performed such that TVO (the opening degree of the throttle valve of the engine 3) is fully opened, and a command signal MCL for connecting the second clutch 7 is provided.
2 = 1 and the output shaft of the second motor 5 and the engine 3
Is connected (S8).

Next, a command signal is output so as to generate the maximum torque to the second motor 5 to increase the rotation speed of the engine 3 (S9), and the accelerator sensor signal AC =
It is determined whether or not 0 (accelerator not operating) (S10), and when the accelerator sensor signal AC = 1 (accelerator operating) (No)
), A command signal MCL1 = 1 for connecting the first clutch 4 is output, and the output shaft of the engine 3 and the axle of the drive wheels 2 are connected (S11).

Thereafter, the target engine torque TMe, the required torque TMa of the vehicle, and the maximum generated torque TJ of the second motor
As a, TMe = TMa−TJa is calculated (S1
2) Based on the target engine torque TMe, calculate the fuel injection amount by the fuel injection valve and TVO (opening of the throttle valve) (S13), and output the fuel injection amount calculated in S13, a TVO command signal, and the like. Then, the autonomous operation of the engine 3 is started (S14).

Next, it is determined whether or not the TVO is fully open (predetermined opening) (S15), and if the TVO is fully open (Yes).
), It is determined that the engine does not satisfy the required torque, and the subsequent steps (S16 to S18) are skipped. If TVO is not fully opened (smaller than the predetermined opening) (No), Since the required torque has been satisfied, a command signal MCL2 = 0 for disengaging the second clutch 7 is output to disconnect (disconnect) the connection between the output shaft of the second motor 5 and the output shaft of the engine 3 (S16). ). Then the second
A command signal for setting the motor torque to 0 is output (S1
7), the control flag FMG is set to 0 (S18).

In S4, the first clutch connection / disconnection signal CL
When 1 = ON (connection) (in the case of No), it is determined whether or not the control flag FMG = 1 (S20), and the control flag FMG is determined.
If MG = 1 (Yes), the process proceeds to S5, and if control flag FMG = 0 (No), this process ends.

In S5, the brake sensor signal BR =
In the case of 1 (operation) (in the case of No), the control flag FM
It is determined whether or not G = 1 (S21), and the control flag FMG =
If the value is 0 (No), this process ends. S2
1, when the control flag FMG = 1 (in the case of Yes), the command signal M for disengaging the second clutch 7
CL2 = 0 is output, the connection between the output shaft of the second motor 5 and the output shaft of the engine 3 is released (disconnected) (S22), and a command signal for setting the second motor torque to 0 is output (S22). S
23), the motoring of the engine by the second motor 5 is stopped.

Thereafter, the fuel cut flag FFC =
It is determined whether or not fuel supply is being performed (S24). If the fuel cut flag FFC = 0 (supply) (Yes), the fuel cut flag FFC = 1 is output. To stop the fuel supply (S2
5) The control flag FMG is set to 0 (S26), and this process ends. In S24, if the fuel cut flag FFC = 1 (No), the control flag FM
G = 0 (S26), and this process ends.

In S6, when the previous brake sensor signal BRO = 0 (brake is not operated) (Yes)
It is determined whether or not the control flag FMG = 1 (S2).
7) If the control flag FMG is 1 (Yes), the process proceeds to S8, and if the control flag FMG is 0 (No), the process ends.

At S10, the accelerator sensor signal AC
= 0 (accelerator not actuated) (Yes)
It is determined whether or not the engine speed Ne has reached a predetermined value Nidl (S28). If the engine speed Ne has not reached the predetermined value Nidl (No), this is determined. When the process is completed and the engine speed Ne has reached a predetermined value Nidl (in the case of Yes), the second motor speed Nmb = C
A command signal is output so as to satisfy b × Nidl, the engine speed Ne is maintained at the predetermined value Nidl (S29), and this processing ends. Note that Cb is a reduction ratio between the second motor 5 and the engine 3.

FIG. 4 is a diagram showing the relationship between the operation of each part of the embodiment of the present invention and changes in torque, rotation speed, and the like. From the top, (a) is the accelerator opening or accelerator on / off,
(B) brake on / off, (c) change in vehicle speed,
(D) is a change in the first motor torque, (e) is a change in the engine torque, (f) is a change in the engine speed, (g) is a change in the second motor torque, and (h) is a second motor speed. (I) shows ON / OFF of the first clutch, (j) shows ON / OFF of the second clutch, and (k) shows ON / OFF of the air conditioner. The horizontal axis indicates time (t).

Briefly, the accelerator opening is set to 0 (t1 in (a)), and then the brake is turned on (operated).
When this is done (t2 in (b)), the first clutch 4 is turned off (disengaged) (t2 in (i)), the fuel supply to the engine 3 is stopped, and the engine speed drops ((f) in (f)). t
2) Regeneration of energy by the first motor 1 becomes large (t2 in (d)).

In this state, when the brake is turned off (released) (t3 in (b)), the second clutch 7 is turned on (connected) (t3 in (j)), and the second motor 5 starts the engine. Motoring is performed with the maximum torque (t3 in (g)), and the engine speed increases (t3 in (f)).

In this state, when the accelerator opening is increased (t4 in (a)), the first clutch 4 is turned on (connected) (t4 in (i)) and fuel is supplied to the engine 3. Then, the autonomous driving is started (t4 in (e)), and then the second clutch 7 is turned off (disconnected) (see (j)).

Thus, the engine 3 starts up quickly and is accelerated by the driving forces of both the engine 3 and the first motor 1 (see (c)). Note that all the driving force of the second motor 5 is used for preliminary rotation of the engine 3 (motoring).
After the brake is turned off (released), the operation of the air conditioner is stopped until a while after the engine starts autonomous operation (t of (k)).
3).

According to the above-described embodiment of the present invention, when the brake is turned from on (operation) to off (release of operation), the second motor is anticipated to be actuated next. 5, the engine 3 is preliminarily rotationally driven (motoring), and when the accelerator is operated later, fuel is supplied to the engine 3 and the engine 3 is supplied.
Is autonomously operated, the engine 3 is already rotated by the second motor 5 at the start of fuel supply. Therefore, the engine 3 quickly starts up, and the re-acceleration response becomes very good.

When accelerating, the engine 3 and the first motor 1
, The first motor 1 has high acceleration performance while maintaining the acceleration performance.
As a result, a relatively small and low-output motor can be used, and a small-sized and small-capacity battery can be employed. Therefore, the size, weight, and cost of a hybrid vehicle can be reduced. Can be achieved.

Further, when the brake is operated, the engine 3
Is separated, it is possible to regenerate the energy consumed as the engine brake, and it is possible to greatly improve the fuel efficiency by this and the above-mentioned weight reduction.

The embodiments described above are described for the purpose of facilitating the understanding of the present invention, and are not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

[Brief description of the drawings]

FIG. 1 is a diagram showing a main configuration of a hybrid vehicle according to an embodiment of the present invention.

FIG. 2 is a diagram showing input and output of various signals of control means of the hybrid vehicle according to the embodiment of the present invention.

FIG. 3 is a flowchart illustrating processing of a control unit according to the embodiment of the present invention.

FIG. 4 is a diagram showing the relationship between the operation of each part of the embodiment of the present invention and changes in torque, rotation speed, and the like.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... 1st motor 2 ... Drive wheel 3 ... Engine 4 ... 1st clutch 5 ... 2nd motor 7 ... 2nd clutch 8 ... Control means

Claims (6)

[Claims] 1. An engine for driving a driving wheel of a vehicle, a first motor for driving the driving wheel, and a clutch for selectively disconnecting an output shaft of the engine and the driving wheel. A second motor for rotating the output shaft of the engine; a brake state detecting means for detecting a state of a brake; and disengaging the clutch when the brake is in the operating state. A control unit for performing a first control for rotating the engine by the second motor when it is detected that the vehicle has become inactive. 2. An engine control system according to claim 1, further comprising: a rotational speed detecting means for detecting a rotational speed of the engine and the first motor; and an accelerator state detecting means for detecting an accelerator state. A fuel injection valve, wherein the control unit controls the first motor when the accelerator state detection unit detects that the accelerator has changed from the non-operation state to the operation state during the execution of the first control. The driving wheels are driven to rotate, the clutch is engaged, and the opening of the throttle valve and the fuel injection amount by the fuel injection valve are controlled based on the difference between the required torque of the vehicle and the torque of the first motor. The control device for a hybrid vehicle according to claim 1, further comprising a second control. 3. The control means determines whether the opening of the throttle valve is a predetermined opening during the execution of the first and second controls, and determines that the opening is smaller than the predetermined opening. The control device for a hybrid vehicle according to claim 2, wherein the first and second controls are stopped when the control is performed. 4. An accelerator condition detecting means for detecting a condition of an accelerator, and a rotational speed detecting device for detecting a rotational speed of the engine, wherein the control means controls the accelerator condition during the execution of the first control. When the detecting means detects that the accelerator is inactive and the engine speed detected by the engine speed detecting means has reached a predetermined value, The control apparatus for a hybrid vehicle according to claim 1, further comprising a third control for controlling two motors to maintain the rotation speed of the engine at the predetermined value. 5. The control unit stops the first control when the brake state detection unit detects that the brake has changed from a non-operation state to an operation state. 2. The control device for a hybrid vehicle according to claim 1. 6. The engine according to claim 1, wherein the engine has an electronically controlled throttle valve, and the control means fully opens the throttle valve when performing the first control. 1
A control device for a hybrid vehicle according to the above.