JP3350465B2 - Hybrid vehicle control device - Google Patents

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, and more particularly to an improvement for maintaining a good running feeling of a vehicle when recovering kinetic energy of the vehicle by generating power during deceleration. .

[0002]

2. Description of the Related Art As is well known, in a hybrid vehicle having a motor as a power source in addition to an engine, when the vehicle is decelerated, the motor is used as a generator or a separately provided generator is used. By doing so, the kinetic energy of the vehicle can be converted into electric energy, and this can be supplied to the battery as regenerative power (such an operation is called deceleration regeneration). That is, at the time of braking, the kinetic energy of the vehicle can be recovered as electric energy, thereby contributing to an improvement in fuel efficiency.

[0003]

In the above-described hybrid vehicle, a variety of operation controls that do not exist in a normal vehicle (a vehicle other than a hybrid vehicle) are required, so that a good driving feeling is obtained. Great care must be taken to ensure

For example, in a general vehicle, control for permitting / stopping fuel supply to an engine during acceleration / deceleration may be employed in order to improve fuel efficiency. In this case, normally, in order to prevent the engine from stalling, when the engine speed decreases to a predetermined speed during deceleration, control for restarting fuel supply to the engine is simultaneously adopted. If we simply applied it to the vehicle,
Even if the fuel supply is restarted to prevent stall as described above, if the motor or generator continues to generate power, the engine output will defeat the braking torque accompanying deceleration regeneration and the engine will stall. The inconvenience of doing so occurs. In order to avoid such inconvenience, if the deceleration regeneration is stopped at the same time as the resumption of fuel supply, the increase in the engine speed due to the resumption of fuel supply will occur almost simultaneously with the loss of braking torque due to the deceleration regeneration. As a result, acceleration is applied to the vehicle at once, and this is perceived by the driver as a shock in the traveling direction.

[0005] Separately, if the power required for the operation of the air conditioner is obtained from the engine output when performing deceleration regeneration in the hybrid vehicle, the braking force associated with the operation of the air conditioner is obtained during deceleration regeneration. Both the braking force and the braking force due to the deceleration regeneration act as an engine brake, so that the braking force becomes excessive and a good running feeling is hindered.

In view of such circumstances, an object of the present invention is to provide a technique capable of performing deceleration regeneration of a hybrid vehicle while ensuring a good running feeling. Specifically, first, a control for permitting / stopping the fuel supply to the engine during acceleration / deceleration is employed, and when the engine speed drops to a predetermined speed during deceleration, the engine is re-started. When adopting the control of restarting the fuel supply to the engine, even if the deceleration regeneration is performed simultaneously with the allowance / stop of the fuel supply, the inconvenience such as the stop of the engine or the shock in the traveling direction is prevented. The purpose is to provide a simple control device. A second object is to provide a control device that can perform deceleration regeneration without feeling excessive braking force even during operation of the air conditioner.

[0007]

Means for Solving the Problems In order to solve the above problems, the present invention employs the following means. That is, the control device for a hybrid vehicle according to claim 1 uses an engine (for example, the engine E in the embodiment) and a motor (for example, the motor M in the embodiment) as power sources of the vehicle, and controls the engine. A hybrid vehicle (for example, hybrid vehicle 1 in the embodiment) provided with a power storage device (for example, battery 2 in the embodiment) that converts an output or a part of the kinetic energy of the vehicle into electric energy by the motor and stores the power. And a control device for controlling the running of the hybrid vehicle, the engine speed (for example, the engine speed N in the embodiment)
E) an engine speed detecting means (for example, engine speed sensor S ₂ in the embodiment) for stopping the fuel supply to the engine when the vehicle decelerates, and the engine speed during the deceleration. Is reduced to a predetermined return rotation speed (for example, the return rotation speed NFCT in the embodiment), the fuel supply amount control means (for example, in the embodiment) configured to allow the fuel supply to the engine again. In the case where a part of the kinetic energy of the vehicle is converted into electric energy by the motor at the time of deceleration and the vehicle is braked,
Power generation amount determining means (for example, blocks B2 and B3 in the embodiment) for determining a power generation amount to be generated (for example, the motor power generation amount REGEN in the embodiment) based on the engine speed. The power generation amount determination means is configured to determine the power generation amount so as to gradually decrease as the engine speed decreases, and to determine the power generation amount to 0 when the engine speed is equal to or lower than the return speed. It is characterized by having.

[0008] With such a configuration, in the control device for a hybrid vehicle, when the engine speed is reduced to the return speed during deceleration regeneration,
It is possible to prevent the engine from stalling due to the engine output defeating the regenerative braking force.

The control device for a hybrid vehicle according to a second aspect is the control device for a hybrid vehicle according to the first aspect, wherein the power generation amount determining means determines that the engine speed is equal to the return speed and the return speed. A predetermined threshold value larger than (for example, the threshold value (NFCT +
DNERGN)), the power generation amount is set so as to gradually approach zero as the engine speed approaches the return speed.

With this configuration, according to this hybrid vehicle control device, when the engine speed reaches the return speed, the power generation amount due to deceleration regeneration does not suddenly become zero. Therefore, in this case, it is possible to prevent an unexpected shock from acting on the occupant due to a sudden stop of the deceleration regeneration.

A control device for a hybrid vehicle according to a third aspect is the control device for a hybrid vehicle according to the first or second aspect, wherein an auxiliary device mounted on the vehicle (for example, an air conditioner HAC according to the embodiment). ) And an electric load detecting means (for example, an air conditioner switch S ₈ in the embodiment) for detecting the presence or absence of an electric load, and the power generation to be regenerated and generated by the motor during the deceleration according to the presence or absence of the electric load by the auxiliary device. Power generation amount setting means (for example, data table #REGENBRHA in the embodiment) for setting the amount based on the engine speed.
C, #REGENBR, #REGENHAC, #REG
EN), the power generation amount determining means refers to the engine speed and a set value set by the power generation amount setting means when determining the power generation amount, and the electric load detecting means. Thus, when it is detected that there is an electric load by the accessory, the amount of power generation at the same engine speed is reduced as compared to when it is detected that there is no electric load. It is characterized by:

[0012] With this configuration, when the hybrid vehicle is equipped with an auxiliary device such as an air conditioner, for which the power required for operation is burdened by the engine, the regeneration during the operation of the auxiliary device is performed. The braking force can be reduced as compared with the case where the auxiliary machine is not operating. Thereby, the feeling of braking during deceleration does not become excessive due to the operation of the auxiliary machine.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. First, an overall outline of a hybrid vehicle to which the present invention is applied will be described.

. FIG. 1 is a diagram showing an embodiment of the present invention, and reference numeral 1 in the figure indicates a hybrid vehicle.
The hybrid vehicle 1 has a configuration in which the motor M connected to the engine E assists the driving of the drive shaft of the engine E, and at the time of deceleration, the motor M is used as a generator to supply power to the battery 2. It is formed as a parallel hybrid vehicle.

In the hybrid vehicle 1, the driving forces of both the engine E and the motor M are transmitted to the front wheels Wf, Wf as driving wheels via a transmission T composed of an automatic transmission or a manual transmission. Also, when the driving force is transmitted from the front wheels Wf, Wf to the motor M during deceleration of the hybrid vehicle 1, the motor M functions as a generator to generate a so-called regenerative braking force, and the kinetic energy of the vehicle body is converted to electric energy. To be collected.

The drive and regenerative operation of the motor M are performed by the power drive unit 4 in response to a control command from the motor ECU 3. The power drive unit 4 includes
The motor M is connected to the battery 2 for transmitting and receiving electric energy. The battery 2 is, for example, one in which a plurality of cells are connected in series and one module is further connected in series. The hybrid vehicle 1 is equipped with a 12-volt auxiliary battery 5 for driving various accessories, and the auxiliary battery 5 is connected to the battery 2 via a downverter 6.
The downverter 6 controlled by the FIECU 8 lowers the voltage of the battery 2 to charge the auxiliary battery 5.

The FIECU 8 controls the operation of the fuel supply amount control means 9 for controlling the amount of fuel supplied to the engine E and the operation of the starter motor 10 in addition to the motor ECU 3 and the downverter 6, and also the ignition timing and the like. Control. For this purpose, the following signals (1) to (5) are input to the FIECU 8. Driven wheel serving rear wheels Wr, signals from a vehicle speed sensor S ₁ for detecting the vehicle speed V based on the rotation speed of the Wr, the signal from the engine speed sensor S ₂ for detecting the engine rotational speed NE, the shift position of the transmission T signal from the shift position sensor S ₃ for detecting the signal from a brake switch S ₄ for detecting operation of a brake pedal 11, a signal from a clutch switch S ₅ for detecting operation of a clutch pedal 12, for detecting the throttle opening TH a signal from an air intake passage pressure sensor S ₇ for detecting the signal air intake passage pressure PB from a throttle opening sensor S _6, a signal from the air conditioner switch S ₈ for performing ON / OFF of the air conditioner HAC.

In FIG. 1, reference numeral 21 denotes a CVT ECU for CVT control, and reference numeral 31 denotes a CVT ECU for protecting the battery 2 and a remaining capacity SO of the battery 2 as described later.
4 shows a battery ECU that calculates C.

Further, the fuel supply amount control means 9 is configured to perform control for stopping fuel supply to the engine E when the hybrid vehicle 1 is decelerating or idling to improve fuel efficiency. At this time, under certain conditions (details are omitted), in order to prevent the engine E from stalling, when the engine speed NE decreases to a predetermined return speed NFCT, the engine E The fuel supply to the engine E is resumed, and the engine E is maintained in the idling operation state.

In such a hybrid vehicle 1, the motor M operates in each of "idle mode", "deceleration mode", "acceleration mode" and "cruise mode" depending on the running conditions and the engine state. Has become.

Of these, the "idle mode" is an operation mode for maintaining the engine E in an idling state by continuously supplying fuel intermittently. The “deceleration mode” is an operation mode of the motor M when the hybrid vehicle 1 performs deceleration regeneration, and the “acceleration mode” is an operation mode when the engine E is assisted by the driving force of the motor M. .

The "cruise mode" is an operation mode in which the hybrid vehicle 1 is driven by the driving force of the engine E without driving the motor. However, also in this case, the motor M is used as a generator for supplying electric power to the accessories.

The selection of each of these operation modes is specifically performed in the FICU 8 based on a flowchart as shown in FIG. In the flowchart shown in FIG. 2, step S1 is a step for performing a discharge depth limit determination. Here, the discharge depth limitation is to suppress the decrease in the remaining capacity of the battery 2 when the remaining capacity of the battery 2 decreases by a predetermined depth from the initial remaining capacity at the start of the vehicle running. Is the operation of
In this step S1, it is determined whether or not the above operation should be performed based on the remaining capacity of the battery 2. Note that the determination result here is the acceleration mode in step S8,
And the cruise mode in step S9, but detailed description thereof will be omitted.

Step S2 is a step for making an assist trigger determination. Here, the assist trigger determination is an operation for determining whether the motor M needs to assist the engine E based on the remaining capacity of the battery 2. Here, the remaining capacity SOC of the battery is in the normal use area (for example, from 40% of the battery capacity to 80 to 90%).
%), The engine M is actively assisted by the motor M. When the remaining battery charge SOC is smaller than the normal use area, the motor M assists the engine E. Not performed (details are omitted).

Step S3 is a throttle fully closed flag F
This is a step for confirming how _THIDLMG is set. Here, the throttle fully closed flag F_THIDLMG is a flag for determining whether the throttle valve 13 of the engine E is closed or open. If the throttle valve 13 is fully closed, the throttle fully closed flag F_THIDLMG is set to “ When it is set to "0" and the throttle valve is open, it is set to "1".

Step S4 is a step for determining whether or not the vehicle speed V detected by the vehicle speed sensor S1 is 0, that is, whether or not the vehicle is stopped.
Step S5 is a step for checking how the motor assist determination flag F_MAST, which is a flag for determining whether the motor M needs to assist the engine E, is set.

On the basis of the results of steps S1 to S5, the operation modes of the motor M are changed to an idle mode (step S6), a deceleration mode (step S7), an acceleration mode (step S8) and a cruise mode (step S9). , And steps S6 to S
In step S10, the operation output of the motor M is performed based on various values set in each mode of No. 9.

If the hybrid vehicle 1 is decelerating and the engine E is not stalled, the operation of the FIICU 8 based on the flowchart of FIG. 2 is as follows.

First, in step S1, a discharge depth limit determination is made according to a predetermined procedure (details are omitted). In step S2, an assist trigger determination is performed according to a predetermined procedure (details are omitted). Move to S3. In step S3, since the hybrid vehicle 1 is decelerating and the throttle 13 is in the fully closed state, the throttle fully closed flag F_THIDLMG
Is determined to be "0", and the process proceeds to step S4.
In step S4, since the vehicle speed V is not 0, the deceleration mode in step S7 is selected as the operation output mode of the motor M.

Next, details of the processing in the "deceleration mode" of step S7 will be described with reference to the flowchart of FIG. As shown in FIG. 3, this "deceleration mode"
Has a schematic configuration including blocks B1, B2, and B3. Among them, the block B1 is an MT vehicle, whether the clutch is engaged, a CVT vehicle, whether the shift position is a neutral (N) position or a parking (P) position, or other. This is a block for determining whether or not the hybrid vehicle 1 is in a state in which deceleration regeneration should be performed based on the shift position.

The blocks B2 and B3 determine the regenerative power generation by the motor M (motor power generation: REGEN) when it is determined in the block B1 that deceleration regeneration should be performed. It is a block to do.

Of these, in block B2,
The motor power generation amount REGEN is searched from the engine speed NE by a predetermined data table.
In this case, the data table is switched depending on whether the air conditioner HAC is operating.

A block B3 is a block for correcting the motor power generation amount REGEN searched in the block B2. This correction is performed to prevent the engine E from stopping when the fuel supply is stopped by the fuel supply amount adjusting means 9 during deceleration, and when the fuel supply is restarted by the fuel supply amount adjusting means 9. This is performed in order to prevent the driver from feeling excessive braking force.

Hereinafter, the details of the processing in the flowchart of FIG. 3 will be described. First, in step S100, it is determined whether the mode is the deceleration mode. If it is determined that the mode is the deceleration mode, the process proceeds to step S102. On the other hand, if it is determined in step S100 that the mode is not the deceleration mode, “0” is set to the motor power generation amount REGEN in step S101, and the process proceeds to step S102.

Here, as described above, the motor power generation amount REGEN is a variable for defining the power generation amount to be generated by the motor M when the battery 2 is charged using the motor M as a generator. The motor operation output in step S21 is executed based on this amount.

Steps S102 to S105 are processing in block B1. Here, first, step S
At 102, the hybrid vehicle 1 is an MT vehicle or a CV
It is determined whether the vehicle is a T car. If the vehicle is a CVT vehicle, it is determined in step S103 whether the shift position is the neutral (N) position or the parking (P) position, or is other than that.

On the other hand, if it is determined that the vehicle is a MT vehicle in step S102, ON the clutch switch S ₅ in step S104, OFF is determined. Step S10
If the clutch switch S ₅ is determined to OFF at 4, or the shift position is the neutral or in-gear state is determined in step S105.

Then, in step S105, MT
If it is determined that the shift position of the vehicle is in the in-gear state, or if it is determined in step S103 that the shift position of the CVT vehicle is neither the neutral (N) position nor the parking (P) position, the process proceeds to step S103. Block B2 following S108
Proceed to.

If it is determined in step S103 that the shift position is either the N position or the P position, then in step S104 the clutch switch S
₅ is determined to be ON, and step S105
Is determined to be neutral in step S106, the motor power generation amount REGEN is set to "0" in step S106, and the deceleration regeneration determination flag F_REG is set to "0" in step S107. That is, in this case, the regenerative braking by the motor M is not performed.

On the other hand, in the block B2, first, in step S108, a brake switch S ₄ is ON
Or OFF. Brake switch S ₄ is ON
It determines if it is determined that the the air conditioner HAC is whether the ON in step S109, with reference to the input signal from the air conditioner switch S _8. Then, when the air conditioner HAC is ON, in step S110, #REGENBRHAC which is a data table when the air conditioner is ON is used.
A table search for the motor power generation amount REGEN is performed to determine the motor power generation amount REGEN. If the air conditioner HAC is off, step S111
Is a data table when the air conditioner is turned off.
The motor power generation amount REGEN is determined by performing a table search of the motor power generation amount REGEN using REGENBR.

Here, data table #REGENBR
HAC and #REGENBR are engine speed NE
4 corresponds to a power generation amount setting means for determining the motor power generation amount REGEN from FIG. 4. When the engine speed NE is plotted on the horizontal axis and the motor power generation amount REGEN is plotted on the vertical axis, it is schematically shown in FIG. Can be expressed As shown in the figure, in the data tables #REGENBRHAC and #REGENBR, the motor power generation amount REGEN is set to gradually decrease as the engine speed NE decreases.

As shown in FIG. 4, #REGEN
In BRHAC, compared to #REGENBR,
For the same engine speed NE, the motor power generation amount REGE
N is set to be at a lower position for the following reason. That is, during the operation of the air conditioner HAC, the power required for operating the air conditioner HAC is obtained from the output of the engine E, so that the power related to the operation of the air conditioner HAC acts as a braking force for the engine E. Will be done. Therefore, when the air conditioner HAC is ON, both the braking force related to the operation of the air conditioner HAC and the braking force generated by generating electric power using the motor M during the deceleration regeneration act as engine brakes. This is because there is a concern that the power will be excessive and hinder a good running feeling for the passenger.

Note that these data tables #REGE
NBRHAC and #REGENBR are MT vehicles and CVs
The setting is made separately for the T car, and for the MT car, it is set so that it can be changed for each gear position.

On the other hand, in step S108, when the brake switch is determined to be OFF is also based on the output of the air conditioner switch S ₈ at step S112, it is determined whether the air conditioner HAC is turned ON You. If it is determined in step S112 that the air conditioner HAC is ON, a table search is performed in step S113 using #REGENAC, which is a data table for turning on the air conditioner, to determine the motor power generation amount REGEN. In step S112, the air conditioner HAC is turned off.
If it is determined to be F, in step S114, a table search is performed using #REGEN, which is a data table for turning off the air conditioner at the time of the brake operation, to determine the motor power generation amount REGEN.

These data tables #REGENHA
C and #REGEN correspond to the data table # described above.
Like REGENBRHAC and #REGENBR, it corresponds to a power generation amount setting means for determining the motor power generation amount REGEN from the engine speed NE.
As shown in FIG. 5, #REGENHAC is
Compared to GENBR, at the same engine speed NE,
The motor power generation amount REGEN is set at a lower position. The reason is that #REGENBRHAC and #
This is the same as the reason why REGENBR is set to a different value.

Note that these data tables #REGE
NHAC and #REGEN are data tables (#REGENBRHAC and #REG) when the brake is not operated.
ENBR), the motor power generation amount REGEN becomes gradually smaller as the engine speed NE becomes smaller, and is set separately for the MT vehicle and the CVT vehicle. The setting is made such that the gear can be changed for each gear position.

[0046] When the brake switch S ₄ is ON, to that to adopt a different data tables If OFF is due consideration for optimal braking force corresponding to the deceleration demanded by the driver Things. That is, when the driver is stepping on the brake, the driver is considered to have a will to decelerate.In this case, the deceleration regeneration amount is set to be larger than when the brake is not depressed. By setting so as to achieve, a braking force that satisfies the driver's deceleration request is realized. Therefore, data tables #REGENBRHAC and #REGENBR at the same engine speed NE
Is set to be larger than the power generation by the data tables #REGENHAC and #REGEN.

As described above, when the processing in block B2 (the processing in steps S108 to S114) is completed,
Next, in step S115, it is determined whether the energy storage zone D determination flag F_ESZONED is “1” or “0”.

Here, the energy storage zone D determination flag F_ESZONED indicates that the remaining battery charge SOC, which is the remaining charge of the battery 2, corresponds to the zone D described below.
Is a flag for indicating whether or not there is a

Here, zoning of the remaining battery charge SOC (so-called remaining capacity zoning) will be briefly described. In the hybrid vehicle 1, the remaining battery charge SOC is divided into a plurality of zones and handled. I have to do that. In this case, specifically, the zone A (SOC 40% to SOC 80% to 90%) which is a normal use area is specifically used.
%), The zone B (from SOC 20% to SOC 40%), which is a provisional use area, is provided below the area B.
Zone C which is an overdischarge area (from SOC 0% to SOC 20
%), And a zone D (SOC 80% to 90% to 100%) which is an overcharge area is set above the zone A.
Is set. Remaining battery capacity SO in each zone
C is detected by the battery ECU 31 in zones A and B.
Is performed by integrating current values, and the zones C and D are performed by detecting a voltage value due to the characteristics of the battery. Based on these results, the energy storage zone A determination flag F_ESZONEA and the energy storage zone B determination flag F_ESZONE corresponding to which zone the remaining battery capacity is in
B, energy storage zone C determination flag F_ES
ZONEC and the energy storage zone D determination flag F_ESZONED are set to “0” or “1” in advance.

Of these zones A, B, C, and D, zone D is not used for control because a voltage change occurs due to overcharging. Therefore, even when the vehicle is decelerating, when the remaining battery charge SOC is in zone D, there is no need to perform regenerative braking, and in step S114, the energy storage zone D determination flag F_E
If it is determined that SZONED is "1", the process proceeds to step S106, and the motor power generation amount REGEN is set to "0".
, And the deceleration regeneration flag F_REG is set to “0” in step S107. That is, also in this case, the regenerative braking by the motor M is not performed.

On the other hand, in step S115, the energy storage zone D determination flag F_ESZONED is set to "0".
If it is determined that the conditions are the same, steps S116 and S1
It proceeds to block B3 consisting of seventeen.

In block B3, first, in step S116, a fuel cut correction coefficient KRGNFC corresponding to the engine speed NE is searched from a predetermined data table. Then, in step S117, the motor power generation amount REGEN determined in block B2 is corrected by the correction coefficient KRGNF.
The value is multiplied by C. That is, block B
In 3, the motor power generation amount REGEN searched in block B2 is calculated using the correction coefficient KRGNFC.
The correction according to the engine speed NE is performed.

Here, the correction coefficient KRGNFC is determined as shown in FIG. FIG. 6 shows the engine speed N
5 is a graph in which E is plotted on the horizontal axis and the correction coefficient KRGNFC is plotted on the vertical axis. As shown in the figure, the correction coefficient KRGN
The FC gradually increases from 0 to 1 as the engine speed NE increases from the return speed NFCT to a threshold value (NFCT + DNERGN) obtained by adding the correction value DNERGN to the return speed NFCT. Stipulated. When the engine speed NE is equal to or more than the threshold value (NFCT + DNERGN), the engine speed NE is set to a constant value “1” and the return speed NFCT
In the following cases, it is set to a constant value “0”.

Note that the return rotation speed NFCT is a threshold when the fuel supply is restarted so that the engine E does not stall when the fuel supply amount control means 9 controls to cut off the fuel supply during deceleration. It is a value determined as a value. That is, the fuel supply amount control means 9 functions to perform fuel cut during deceleration, and to restart fuel supply when the engine speed NE decreases to the return speed NFCT. Further, the threshold value (NFCT + DNERGN) is specifically set to a value 200 to 300 rotations larger than the engine stall determination rotation speed NCR.

The reason why the correction coefficient KRGNFC is determined in this way is as follows. That is, FIG.
As shown in (b), the vehicle speed V and the engine speed NE
Is decreasing with the passage of time T, the fuel supply amount control means 9 determines the fuel supply amount Ti to the engine E as shown in FIG.
Control is performed as shown in FIG. That is, the fuel supply is stopped from the deceleration start time T1 to the time T2 when the engine rotational speed NE has decreased to the return rotational speed NFCT. After the time T2, the fuel supply is stopped again by the same amount as before the deceleration start time T1. Fuel supply will be performed.

In this case, the motor power generation amount REGEN accompanying the deceleration regeneration is as shown in FIG. FIG.
In (d), in addition to the corrected motor power generation amount REGEN calculated in step S117, the uncorrected motor power generation amount REGEN set in block B2 is indicated by a broken line. Here, the motor power generation amount R
When EGEN is set as shown by the broken line (before correction), the deceleration regeneration is still performed even when the engine speed NE becomes equal to or lower than the return speed NFCT. Although the fuel supply is restarted in order to prevent the engine E from being stalled in several NFCTs, there is a concern that the output torque of the engine E defeats the torque required for regeneration and eventually the engine E is stalled. Therefore, when the engine speed NE is equal to or lower than the return speed NFCT, the correction coefficient KRGNFC
Is set to “0” to ensure that the corrected value of the motor power generation amount REGEN becomes 0.

In this case, for example, as shown by the dashed line in FIG. 7 (d), if the motor power generation amount REGEN is simply corrected at time T2 to become 0, the regeneration at time T2 is performed. The braking is suddenly stopped, and in this case, the passenger of the hybrid vehicle 1 feels a shock in the traveling direction. In particular, at time T2, when the fuel supply is restarted, the rotation speed of the engine E temporarily increases, and this is transmitted to the occupant as a shock in the traveling direction, so that the shock felt by the occupant is further increased. It could be noticeable. Therefore,
The correction coefficient DNERGN is calculated by changing the engine speed NE from the threshold value (NFCT + DNERGN) to the return speed NFCT.
Is gradually reduced from 1 to 0 as the vehicle speed approaches, thereby causing the motor power generation amount REGEN to gradually approach 0, thereby reducing the engine speed NE to the return speed NF.
It is gradually weakened before the CT is reached, so as to reduce the shock acting on the passenger.

In the present embodiment, the threshold value (NFCT + DNERGN) is set to a value 200 to 300 rotations larger than the engine stall determination rotation speed NCR. To avoid stall, the engine E
Assuming a neutral point between the torque acting in the direction in which the rotation returns and the torque due to the regenerative braking, the value of the engine speed NE at this neutral point is taken into consideration, and the engine speed NE within the processing time of the flowchart of FIG. It is determined in consideration of the fluctuation of. Therefore, the threshold value (NF
CT + DNERGN) is the engine stall judgment number NCR
How large the value becomes compared to the above will vary in accordance with the performance of the vehicle to be controlled.

When the processing in block B3 is completed,
Next, in step S118, the motor power generation amount REG
EN is compared with a regeneration enable / disable determination threshold value #RGNLLG, and when REGEN ≦ # RGNLLG, step S is executed.
Proceed to 106 and S107, that is, deceleration regeneration is not performed. Here, the regeneration possibility determination threshold value #R
GNLLG is a value set as the lower limit of the deceleration regeneration amount. When the motor power generation amount REGEN determined according to the engine speed NE becomes smaller than this value, the rotation speed NE of the engine E also decreases. If a negative torque is applied to the engine E by the deceleration regeneration, it is considered that inconvenience such as a burden on the engine E occurs. In this case, it is determined that the deceleration regeneration is stopped. That's what I did.

When REGEN>#RGNLLG, the process proceeds to step S119, where the deceleration regeneration determination flag F_REG is set to "1". Then, in both the case where the deceleration regeneration determination flag F_REG is set to “1” in step S119 and the case where the deceleration regeneration determination flag F_REG is set to “0” in step S107, 1
The power corresponding to the 2 volt power consumption is calculated, and this power is supplied to the auxiliary battery 5 by power generation through regeneration of the motor M. In this case, the power corresponding to the 12 volt power consumption is determined from the difference between the charging and discharging currents in the battery 2 and the regenerative power generation of the motor To do. In this case, the motor M is controlled by the motor E
This is performed in CU3. Further, in step S121, the assist power ASTPWR, that is, the assist amount of the engine E by the motor M is set to “0”,
To return.

In the processing of the "deceleration mode" in the hybrid vehicle 1 as described above, blocks B2 and B
3, the motor power generation amount REGEN is set to "0" when the engine speed NE is equal to or lower than the return speed NFCT. Therefore, when the fuel supply by the fuel supply amount control means 9 is restarted, the engine return torque reduces the regenerative braking. The stall of the engine E can be reliably prevented without being damaged by the torque. Thus, there is no fear that the engine E stops against the driver's will, and traveling comfort can be ensured.

Further, in the above-described processing, as the engine speed NE approaches the return speed NFCT from the threshold value (NFCT + DNERGN), the motor power generation amount REGEN gradually approaches zero. In the case where the fuel supply is restarted by the step 9, the sudden deceleration and regeneration are stopped, so that an unexpected shock in the traveling direction can be prevented from acting on the occupant. Can be realized.

In the above-described processing, when the air conditioner HAC is ON, the motor power generation amount REGE when the engine speed NE is the same as compared to when the air conditioner HAC is OFF.
Since N is set to a low value, during deceleration regeneration, excessive braking caused by both the braking force generated by operating the air conditioner HAC and the regenerative braking force generated by the motor M acting as an engine brake. This makes it possible to alleviate the feeling of braking and to ensure a good running feeling.

Further, in the above processing, data tables #REGENBRHAC, #REGEN for setting the motor power generation amount REGEN according to the engine speed NE.
Since BR, #REGENHAC, and #REGEN are used, and one of these data tables is referred to when determining the motor power generation amount REGEN, the engine speed sensor S _The air conditioner HAC is turned on based on the engine speed NE input from ₂ to FICU8.
/ Motor output R appropriate for each time
EGEN can be easily determined without performing calculations or the like, and quick processing can be realized.

In the above, one embodiment of the present invention has been described. However, the present invention is not limited to the above-described embodiment, and other configurations may be adopted as needed without departing from the gist of the present invention. It is also possible.

For example, in the processing of block B2 in the above embodiment, the air conditioner HAC is turned on / off.
At the time of FF, the motor power generation amount REGEN is searched in a separate data table.
When the air conditioner HAC is turned on, the motor power generation amount R is calculated using a predetermined correction coefficient or correction value.
EGEN may be reduced.

[0067] Further, in the embodiments described above, we have used a shift position sensor S ₃ for detecting the shift position of the transmission T, in particular, in the manual transmission vehicle, instead of this, the engine rotational speed NE Alternatively, a configuration for detecting a shift position from vehicle speed V may be adopted.

[0068] Further, in the above embodiment, although the ON / OFF of the air conditioner HAC had to be detected by the air conditioner switch S _8, instead of this, ON / OFF from the clutch switch the air conditioner HAC May be detected, or ON / OFF of the air conditioner HAC may be detected using other means for detecting the electric load of the air conditioner HAC.

Further, in the above embodiment, the motor power generation amount REGEN at the same engine speed NE is reduced according to ON / OFF of the air conditioner HAC, but the operation imposes a burden on the engine E. For such other auxiliary equipment, an electric load detecting means for detecting an electric load accompanying the operation of the auxiliary equipment is provided, and when the electric load is detected, the electric load is compared when the electric load is not detected. Alternatively, control may be performed to reduce the motor power generation amount REGEN.

[0070]

As described above, according to the control apparatus for a hybrid vehicle according to the first aspect, the amount of power generation when the engine speed is equal to or lower than the return speed is set to 0, so that the fuel supply When the fuel supply is restarted by the amount control means, the engine return torque is not impaired by the regenerative braking torque, and the engine stall can be reliably prevented. As a result, it is possible to eliminate the concern that the engine will stop against the driver's will and to ensure the traveling comfort.

According to the control device for a hybrid vehicle according to the second aspect, as the engine speed approaches the return speed from a predetermined threshold value, the power generation amount gradually approaches zero. In the case where the fuel supply is restarted by the means, the sudden deceleration and regeneration are stopped, so that an unexpected shock in the traveling direction can be prevented from acting on the occupant, thereby improving the driving feeling. Can be realized.

According to the control device for a hybrid vehicle according to the third aspect, when the auxiliary machine is operating, the motor power generation amount when the engine speed is the same is compared with when the auxiliary machine is not operating. Since the low value is set, during deceleration regeneration, the braking force generated by the operation of the auxiliary device and the regenerative braking force can alleviate excessive braking feeling caused by acting as an engine brake, Good running feeling can be ensured. Also, in this case,
Since the power generation amount setting means for setting the power generation amount due to the deceleration regeneration in relation to the engine rotation speed is used, an appropriate power generation amount is calculated based on the engine rotation speed and the detection result of the electric load by the auxiliary machine. Search and determination can be easily performed without performing, and quick processing can be realized.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a hybrid vehicle schematically showing an embodiment of the present invention.

FIG. 2 is a flowchart illustrating a procedure of a motor operation mode determination performed in the hybrid vehicle illustrated in FIG. 1;

FIG. 3 is a flowchart showing details of processing in a deceleration mode in the flowchart shown in FIG. 2;

FIG. 4 is a graph schematically showing set values of a data table used in processing in the flowchart shown in FIG. 3;

FIG. 5 is a graph schematically showing setting values of another data table.

6 is a graph showing set values of a correction coefficient used in the processing in the flowchart shown in FIG. 3 in relation to an engine speed.

7A and 7B are diagrams showing temporal changes in various amounts when the hybrid vehicle shown in FIG. 1 is decelerated, where FIG. 7A is a graph showing temporal changes in vehicle speed, and FIG. 7B is a graph showing engine speed. A graph showing a temporal change, (c) is a graph showing a temporal change of a fuel supply amount, and (d) is a graph showing a temporal change of a motor power generation amount.

[Explanation of symbols]

Reference Signs List 1 hybrid vehicle 2 battery (power storage device) 8 FICU 9 fuel supply control means E engine M motor HAC air conditioner (auxiliary equipment) S ₂ engine speed sensor (engine speed detection means) S ₈ air conditioner switch (electric load detection Means) Blocks B2, B3 Power generation amount determination means #REGENBRHAC, #REGENBR, #REG
ENHAC, #REGEN data table (power generation amount setting means) NE engine speed REGEN motor power generation NFCT return rotation speed NFCT + DNERGN threshold value

──────────────────────────────────────────────────の Continuation of front page (51) Int.Cl. ⁷ Identification code FI F02D 29/06 F02D 41/12 330K 41/12 330 H02J 7/14 C H02J 7/14 B60K 9/00 ZHVE (72) Inventor Yoshitaka Kuroda 1-4-1 Chuo, Wako City, Saitama Prefecture Inside Honda Technical Research Institute Co., Ltd. (72) Inventor Atsushi Matsubara 1-4-1 Chuo Wako City, Saitama Prefecture Co., Ltd. Honda Motor Research Institute Co., Ltd. (72) Inventor Nakamoto Yasuo 1-4-1 Chuo, Wako-shi, Saitama Pref. Honda Research Institute, Ltd. (56) References JP-A-10-331675 (JP, A) JP-A-9-284916 (JP, A) JP-A-10- 288063 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B60L 11/14 B60K 6/02 F02D 29/02-29/06 F02D 29/06 F02D 41/12 330 H02J 7 / 14

Claims (3)

(57) [Claims] 1. A hybrid vehicle comprising an engine and a motor as power sources for a vehicle, and a power storage device for converting a part of the output of the engine or kinetic energy of the vehicle into electric energy by the motor and storing the power. A control device for controlling the running of the hybrid vehicle, comprising: an engine speed detecting means for detecting an engine speed; and stopping fuel supply to the engine when the vehicle decelerates. A fuel supply amount control unit configured to permit supply of fuel to the engine again when the engine speed decreases to a predetermined return speed during the deceleration; and When a part of the kinetic energy of the vehicle is converted into electric energy by the motor to perform braking of the vehicle, Power generation amount determining means for determining a power generation amount to be regenerated and generated by a motor based on the engine speed, wherein the power generation amount determination means gradually reduces the power generation amount as the engine speed decreases. A control device for a hybrid vehicle, wherein the control device is determined to be small, and is set to 0 when the engine speed is equal to or less than the return speed. 2. The control device for a hybrid vehicle according to claim 1, wherein the power generation amount determination unit determines a value of the engine speed between the return speed and a predetermined threshold value greater than the return speed. A control device for a hybrid vehicle, wherein the power generation amount is set so as to gradually approach zero as the engine speed approaches the return speed when the engine speed approaches the return speed. 3. The control device for a hybrid vehicle according to claim 1, wherein an electric load detecting means for detecting the presence or absence of an electric load by an auxiliary device mounted on the vehicle; Power generation amount setting means for setting, based on the presence or absence, the power generation amount to be regenerated and generated by the motor during the deceleration based on the engine speed, the power generation amount determination means determines the power generation amount In doing so, the engine speed and the set value set by the power generation amount setting means are referred to, and when the electric load detecting means detects that there is an electric load by the auxiliary machine, the electric load is A hybrid vehicle having a configuration in which the amount of power generation at the same engine speed is reduced as compared to a case where no hybrid vehicle is detected. Control device.