JPH09233607A - Drive control device for hybrid vehicle - Google Patents

Abstract

(57) Abstract: A driver does not feel uncomfortable even if the operation of an electric motor is limited due to a difference in the amount of electricity stored in a power storage device. SOLUTION: When the power mode selection switch is operated (S2 is YES) and the stored amount SOC is equal to or more than a certain amount A (S3 is YES), the power to run by operating both the internal combustion engine and the electric motor. If the power mode selection switch is not operated (S5), the motor drive mode or I
Performs normal mode running in CE drive mode.
If S2 is YES and S3 is NO, the power mode disapproval display is performed (S6) and the charging mode traveling for charging while traveling by the internal combustion engine is performed (S7).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drive control device for a hybrid vehicle, and more particularly to a drive control device for a hybrid vehicle capable of power mode traveling in which both an engine and an electric motor are operated for traveling.

[0002]

2. Description of the Related Art A hybrid vehicle is known in which an engine that operates by combustion of fuel and an electric motor that operates by electric energy stored in a power storage device are provided as power sources for running the vehicle. According to such a hybrid vehicle, the fuel consumption amount and the exhaust gas amount are reduced by using the engine and the electric motor separately according to the driving state and traveling. In addition, by suppressing the maximum output of the engine (for example, displacement), and by performing power mode traveling in which both the engine and the electric motor are operated during high load such as climbing a hill, fuel consumption and exhaust gas amount are reduced. There are some that are further reduced.
The device described in Japanese Patent Laid-Open No. 6-80048 is an example of such a device, and is designed to perform the power mode traveling at a high load when the driver depresses the accelerator greatly.

[0003]

However, in such a conventional hybrid vehicle, since the operation of the electric motor is limited when the amount of electricity stored in the electricity storage device decreases, the electric motor operates even when the driver depresses the accelerator. In some cases, a sufficient driving force may not be obtained without a driver, and the driver may feel uncomfortable. That is, even in the same operating state, there is a possibility that the driving state may differ due to the different operating state of the power source.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to prevent the driver from feeling uncomfortable even if the operation of the electric motor is limited due to a difference in the amount of electricity stored in the electricity storage device. To do so.

[0005]

In order to achieve such an object, a first aspect of the present invention provides an engine that operates by combustion of fuel and an electric motor that operates by electric energy stored in a power storage device when the vehicle is running. Equipped as a power source, it can run in normal mode running with maximum torque by operating only one of its engine and electric motor, and with maximum torque combining the driving forces of both engine and electric motor. In a hybrid vehicle capable of various power mode running, (a) a power mode selecting unit operated when the user desires the power mode running, and (b) the power mode selecting unit when the power mode selecting unit is operated. Power mode limiting means for permitting traveling but prohibiting the power mode traveling when not operated. The features.

A second aspect of the invention is characterized in that the drive control device for a hybrid vehicle according to the first aspect of the invention further comprises means for making a normal mode running when the power mode selection means is not operated.

A third aspect of the present invention is the drive control device for a hybrid vehicle according to the first aspect, further comprising: (c) when the amount of electricity stored in the electricity storage device is smaller than a predetermined value, the operation of the power mode selection means is prioritized. The power mode prohibition means for prohibiting the power mode travel, and causing the engine to travel only with the power source as the power source, and (d) the power mode prohibition means prohibiting the power mode travel to the driver. And a power mode disabling display means for informing.

[0008]

In such a drive control device for a hybrid vehicle, unless the power mode selection means is operated, the drive mode of the electric motor is not applied to the engine, and the drive mode is not set to the maximum torque. Since the vehicle can be driven with the maximum torque when only one of the two is operated, when the operation of the electric motor is limited due to a decrease in the amount of electricity stored in the power storage device, for example, the vehicle is driven using the engine as a power source. . As a result, the maximum driving force changes only when the driver intentionally operates it, so that the driver does not feel uncomfortable. That is, it is possible to prevent the maximum torque of the vehicle with respect to the accelerator operation from changing according to the state of the vehicle.

Further, in the third aspect of the invention, when the amount of electricity stored in the electricity storage device is smaller than the predetermined value, the power mode running is prohibited prior to the operation of the power mode selection means, so the amount of electricity stored becomes too small. While the power storage device is prevented from being damaged and the charging and discharging efficiencies are significantly reduced, the driver is informed by the power mode disabling display means that the power mode traveling is prohibited. The driver does not feel uncomfortable due to insufficient driving force due to the stop.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Here, the present invention relates to a switching type in which a power source is switched by connecting / disconnecting power transmission by, for example, a clutch, a combination of a planetary gear device, and the like.
The engine and the electric motor are provided as a power source when the vehicle is running, such as a mixed type that combines and distributes the output of the engine and the electric motor by a distribution mechanism, and an assist type that uses the electric motor as an auxiliary.
The present invention can be applied to various types of hybrid vehicles capable of normal mode running in which only one of the engine and the electric motor is operated to run, and power mode running in which both the engine and the electric motor are operated to run. It may be the case where an electric motor is provided for each drive wheel.

In the normal mode traveling, for example, one of the engine and the electric motor is operated by the normal traveling control means to travel, and the engine and the electric motor are selectively used according to the operating state in order to reduce the exhaust gas amount. However, it is also possible to always travel using only the engine (assist type). The power mode traveling is, for example, a case in which both the engine and the electric motor are operated by the power traveling control means, and when the power mode selecting means is operated, the power mode traveling is unconditionally performed regardless of the operating state. However, in order to reduce the amount of exhaust gas, it is possible to perform power mode traveling only when the operating state (accelerator operation amount, etc.) satisfies predetermined power traveling conditions. desirable. Note that the normal mode running is running with the maximum torque when only one of the engine and the electric motor is operated, usually with a torque equal to or less than the maximum torque of the engine, and not necessarily only one of the engine and the electric motor. It is not limited to the case where the vehicle is driven by driving the vehicle, and there may be the case where the vehicle is driven by operating both the engine and the electric motor, and the essential difference from the power mode traveling is the maximum torque.

The power mode selecting means is operated by the driver's intention, and may be, for example, a changeover switch arranged on an instrument panel or the like and changed over by the driver. It is also possible to configure the power mode selection means by setting a power range to the power lever or providing a push button on the grip of the shift lever or the like.

The predetermined value of the amount of stored electricity for which the power mode prohibiting means prohibits the power mode running is such that it is possible to avoid a significant reduction in charging and discharging efficiency or damage to the electrical storage device due to a decrease in the stored amount of electricity. Is set. The determination of prohibition of the power mode traveling by the power mode inhibiting means may be made only when the power mode traveling is permitted, but may be performed prior to the determination of the power mode limiting means. That is, when the amount of stored electricity is less than the predetermined value, the operation of the electric motor may be stopped and only the engine may be used as the power source regardless of whether the vehicle is traveling in the power mode or the normal mode. As the power mode non-display means, those visually displayed on the instrument panel,
A voice notification is preferably used, and when the power mode running is prohibited by the power mode prohibiting means, a disabling display may be always made, but the power mode selecting means is operated and the power mode running is prohibited. It may be displayed only when there is.

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram illustrating a drive control device 10 for a hybrid vehicle that is an embodiment of the present invention. An internal combustion engine 12 such as a gasoline engine that operates by combustion of fuel and an electric motor that functions as an electric motor and a generator. And 14 as power sources. Internal combustion engine 1
The power of 2 and the electric motor 14 is transmitted to the transmission 16 at the same time or alternatively, and is further transmitted to the left and right drive wheels via the vehicle drive output device 18. The transmission 16 is a speed change mechanism that changes the speed ratio steplessly or decelerates at a constant speed ratio, and the vehicle drive output device 18 is a forward / reverse switching mechanism or a differential device that switches between forward and backward travel. is there. The electric motor 14 is rotated in the reverse direction to move the vehicle backward, or a clutch is provided between the internal combustion engine 12 and the electric motor 14 or between the power source thereof and the transmission 16. It is also possible to appropriately interrupt the power transmission between them.

FIG. 2 is a diagram for concretely explaining an example of a vehicle drive device including the transmission 16 and the vehicle drive output device 18, and the width of the vehicle such as an FF (front engine / front drive) vehicle. It is a horizontal type that is installed almost parallel to the direction. The internal combustion engine 12 and the electric motor 14 are arranged so as to face each other in series on a common first axis,
These output shafts 12a and 14a are connected to each other via a clutch C so that they cannot rotate relative to each other, and a chain drive (sprocket) 100 is attached to the output shaft 14a of the electric motor 14, and The power is transmitted to the power transmission device 104 via the chain 102. The power transmission device 104 includes a toroidal type continuously variable transmission mechanism 106, a planetary gear type speed reduction / reverse mechanism 108, and a bevel gear type differential device 110, which are arranged in series on a second axis parallel to the first axis. Is equipped with
The power is transmitted to the toroidal type continuously variable transmission mechanism 106 via the chain driven (sprocket) 112, and the reduction / reverse rotation mechanism 108 and the differential device 11 are provided.
Through 0, it is output to a drive wheel (not shown) from a pair of transmission shafts 114, 116 arranged on their centers, that is, on the second axis. The toroidal type continuously variable transmission mechanism 106 is a specific example of the transmission 16, and the deceleration / reverse rotation mechanism 108 and the differential device 110 are the vehicle drive output device 1.
8 is a specific example.

The toroidal type continuously variable transmission mechanism 106 is
It transmits torque through traction oil with high viscoelasticity. The figure shows a double-cavity type full toroidal type, in which the inclination angles of variators (rollers) 118a and 118b are continuously controlled by a hydraulic actuator or the like. Thus, the speed ratio with respect to the output shaft 120 is continuously changed. Deceleration / reverse rotation mechanism 108
Are three sets of simple planetary gear units 122, 124, 12
6, a reverse brake B1, and a forward brake B2, and is configured as a toroidal continuously variable transmission mechanism 10.
The output shaft 120 of 6 is the simple planetary gear unit 12
It is integrally connected to 2,124 sun gears. Then, according to the shift operation of the shift lever (not shown), the reverse brake B1 is engaged and the forward brake B is engaged.
2 is released to establish the reverse gear for traveling the vehicle in the reverse direction, and the forward brake B2 is engaged and the reverse brake B1 is released to establish the forward gear for traveling the vehicle forward. By releasing both brakes B1 and B2, a neutral stage (neutral) that cuts off power transmission is established. Further, the deceleration / reverse rotation mechanism 108 is adapted to decelerate (forward gear ratio> 1) at a predetermined gear ratio for both forward and reverse gears, and power is supplied from the carrier of the simple planetary gear device 126 to the differential device 110. Output. In FIG. 2, three sets of simple planetary gear units 122, 12 are provided.
The diameters (gear ratios) of the gears 4, 126 are equal to each other, but the diameters are appropriately set according to the desired gear ratio and the like. Further, the power transmission device 104 has a center line (second axis line).
In contrast to FIG. 2, the lower half from the center line is omitted.

Returning to FIG. 1, the electric motor 14 is M
It is connected to a power storage device 22 such as a battery via a (motor) / G (generator) control device 20, and is supplied with electric energy from the power storage device 22 to be driven to rotate by a predetermined torque. Braking (electric motor 1
By functioning as a generator by the electric braking torque of 4 itself, the power storage device 22 is switched between a charging state in which electric energy is charged and a no-load state in which the motor shaft is allowed to rotate freely. In addition, the internal combustion engine 1
2 is a fuel injection amount control actuator, a throttle control actuator, an ignition timing control actuator,
The operating state is controlled by an ICE (internal combustion engine) control device 24 such as an intake / exhaust valve control actuator. The ICE control device 24 is controlled by a controller 26 together with the M / G control device 20.

The controller 26 is a CPU, RAM, RO
M including a microcomputer having
Signal processing is executed in accordance with a preset program. For example, an ICE drive mode in which only the internal combustion engine 12 is used as a power source for traveling, a motor drive mode in which only the electric motor 14 is used as a power source, and the internal combustion engine 12 is used.
I traveling with both the electric motor 14 and the electric motor 14 as power sources
The vehicle is driven in four driving modes: a CE / motor driving mode and a charging mode in which the electric motor 14 is rotationally driven by the internal combustion engine 12 to generate electric power. The controller 26 includes an engine torque T _E , a motor torque T _M , an accelerator operation amount θ _A , an engine speed N _E , a motor speed N _M , an output speed N _O of the transmission 16, and a power storage amount of the power storage device 22. Information about the SOC and the like is supplied from various detecting means.

The controller 26 is also supplied with a power mode selection signal SP from a power mode selection switch 28 arranged on the instrument panel, the shift lever, or in the vicinity thereof, and also travels in the ICE / motor drive mode. Power mode disable signal SD for visually indicating that power mode running is not possible
Is output to the power mode disabling indicator 30 provided on the instrument panel or the like. The power mode selection switch 28 is operated when the driver desires to switch the traveling mode including the power mode traveling in the ICE / motor drive mode.
It is also possible to use a gear shift pattern select switch or the like that can select a gear shift pattern (power pattern or the like) that emphasizes power performance in the gear shift control of 6. The power mode selection switch 28 corresponds to power mode selection means, and the power mode non-display device 30 corresponds to power mode non-display means.

FIG. 3 is a functional block diagram relating to the traveling mode selecting means 32 for switching the traveling modes in accordance with the driving condition in the series of signal processing by the controller 26. In the ICE driving mode or the motor driving mode, FIG. Normal traveling control means 34 for executing the normal mode traveling, and power traveling control means 3 for executing the power mode traveling in the ICE / motor drive mode.
6. Run in charge mode Run in charge mode I
A CE drive / charge traveling control means 38 is provided.

Further, the power mode limiting means 40 permits the power mode running by the power running control means 36 when the power mode selecting signal SP is supplied from the power mode selecting switch 28, but the power mode selecting signal is allowed. When the SP is not supplied, the power mode running is prohibited and the normal running control means 34 runs only the normal mode running. The power mode prohibiting means 42 permits the power mode traveling by the power traveling control means 36 when the stored amount SOC is equal to or more than a predetermined constant amount A, but when the storage amount SOC is less than the constant amount A, the ICE drive / charge traveling control means. 38 in the charging mode running and the power mode disable signal S
D is output to the power mode prohibition display 30 to visually display that power mode traveling cannot be performed. A certain amount A
Is the minimum required amount of electricity that can be traveled using the electric motor 14 as a power source without significantly impairing charging efficiency or discharging efficiency.

The power / normal switching means 44 is for switching between the power mode traveling and the normal mode traveling depending on whether or not a predetermined power traveling condition is satisfied. Specifically, the instantaneous traveling required power P _L is set in advance. When the value is equal to or larger than the predetermined constant value B, the power travel control means 36 causes the vehicle to travel in the power mode, while when the value is smaller than the constant value B, the normal travel control means 34 causes the vehicle to travel in the normal mode. The fixed value B is set to, for example, the larger one of the maximum powers that the internal combustion engine 12 and the electric motor 14 can output steadily, that is, the maximum power of the internal combustion engine 12 in this embodiment. The instantaneous travel required power P _L includes air resistance and tire rolling resistance, and changes in the engine speed N _E and the engine torque T _E , or the motor torque T _E and the motor speed N _E , and further the accelerator operation amount θ _A. Data (such as an arithmetic expression) that is obtained from a pre-stored data map, etc., using the amount and rate of change as a parameter, and that is necessary for calculating the instantaneous travel required power P _L , such as the data map, is stored in advance in the storage means 52 (FIG. 4)) and the like.

The normal traveling control means 34 is constructed, for example, as shown in FIG. The first calculating means 46 obtains the fuel consumption amount Mfc _m when traveling with the internal combustion engine 12 as a power source according to the following equation (1), and the second calculating means 48 travels with the electric motor 14 as a power source. In this case, the fuel consumption amount Mfc _e when the electric motor 14 is rotationally driven by the internal combustion engine 12 to charge the power storage device 22 with the electric energy required in this case is calculated according to the following equation (2).
Further, the comparison means 50 uses the fuel consumption amounts Mfc _m and Mfc _e.
The smaller driving mode is selected by comparing the magnitudes of. _{Mfc m = FC m × P L} ··· (1) Mfc e = FC e × P L / (η GEN × η BIN × η BOUT × η MOT) ··· (2)

P _{L in the} equation (1) is the power required for the instantaneous running. FC _m is the fuel consumption rate (g / kW when the instantaneous required driving power P _L is taken out by the internal combustion engine 12).
h), engine torque T _E and engine speed N _E
Can be obtained from a data map or the like using as a parameter. FIG. 7 is a diagram showing an example of the equal fuel consumption rate line, in which the shaded area has the smallest fuel consumption rate FC, and a large amount of power can be produced with a small amount of fuel, and the fuel consumption rate FC increases toward the outside. . Since the required instantaneous traveling power P _L is represented by the rotational speed and the torque, the fuel consumption rate FC _m can be obtained from the data shown in FIG. 7 according to the required instantaneous traveling power P _L. Data necessary for calculating the fuel consumption rate FC _m as shown in FIG. 7 is also stored in the storage unit 52 in advance. Note that η _ICEmax in FIG. 7 is the maximum value of fuel consumption efficiency (reciprocal of fuel consumption rate FC), and fuel consumption efficiency η _ICE
Becomes smaller as the fuel consumption rate FC increases toward the outside. Fuel consumption efficiency with η _{ICEmax set} to 1 η _ICE
May be set.

FC of formula (2)_eIs generated by the internal combustion engine 12.
Internal combustion engine 12 at the time of charging by driving the driving motor 14
Fuel consumption rate of η_GEN, Η_BIN, Η_BOUT, Η_MOTHaso
The kinetic energy is converted into electric energy by the electric motor 14, respectively.
Energy conversion efficiency (power generation efficiency) when converting into energy
Energy when charging the electric device 22 with electric energy
Conversion efficiency (charging efficiency), electric energy from power storage device 22
Energy extraction efficiency (discharge efficiency) when extracting
The electric motor 14 converts electric energy into kinetic energy
Energy conversion efficiency (driving efficiency) when Drive
Efficiency η_MOTIs the motor torque T_MAnd motor speed N
_MCan be set as a parameter, and the operating state at that time
Power required for instant driving P_LCan be asked according to
You. FIG. 8 is a diagram showing an example of the equal driving efficiency line, which is shown by diagonal lines.
Part η_MOTmaxIs the driving efficiency η_MOTIs the largest and the least
It is possible to generate great power with energy
Driving efficiency η toward the outside_MOTBecomes smaller. Shun
Power required for traveling P_LIs represented by speed and torque
Therefore, from the data shown in FIG. _L
Drive efficiency η_MOTIs required. Discharge efficiency η_BOUT
Is the storage amount SOC at that time and
Set the amount of electric energy (electric power) to be output as a parameter
When the stored amount SOC is read from the power storage device 22,
In both cases, the electric power is the power P required for the instantaneous travel._LTo accommodate
The amount of stored electricity SOC and the power P required for instantaneous travel_LIn response
Then, from the data map, etc., discharge efficiency η_BOUTIs sought
You. Driving efficiency η_MOT, Discharge efficiency η_BOUTRequired to calculate
Data (data maps, formulas, etc.)
Stored in column 52.

On the other hand, the fuel consumption rate FC _e , the power generation efficiency η _GEN and the charging efficiency η _BIN are values at the time of charging the electricity storage device 22 with the electric energy generated by rotationally driving the electric motor 14 by the internal combustion engine 12. Therefore, the value during traveling in the charging mode is estimated regardless of the current operating state. The charging mode traveling is adapted to be executed according to the flowchart of FIG. 6 when the stored amount SOC is smaller than a predetermined constant amount A, and for example, the fuel consumption rate FC _e in the past charging mode traveling FC _e , Power generation efficiency η _GEN , average value of charging efficiency η _BIN (moving average, etc.),
Alternatively, the fuel consumption rate FC _e , the power generation efficiency η _GEN , and the instantaneous value of the charging efficiency η _BIN during the last charging mode running are stored in the storage means 52 or the like, and the values (learning values) are used. The fuel consumption amount Mfc _e may be calculated. Like the fuel consumption rate FC _m , the fuel consumption rate FC _e is obtained from a data map having the engine torque T _E and the engine speed N _E as parameters as shown in FIG. 7, and the power generation efficiency η _GEN is The charging efficiency η _BIN can be obtained from a data map having the regenerative braking torque and the motor speed N _M as parameters, and the charging efficiency η _BIN can be obtained from the data map having the stored amount SOC and the amount of electric energy (electric power) charged per unit time as parameters. Desired. The amount of electric energy (electric power) charged per unit time corresponds to surplus power of the power of the internal combustion engine 12 that is spent for rotation of the electric motor 14. Power generation efficiency η _GEN , charging efficiency η
_The data (data map, arithmetic expression, etc.) necessary for the calculation of _BIN is stored in the storage means 52 in advance.

Next, the controller 26 drives the vehicle.
An example of dynamic control will be described with reference to the flowchart of FIG.
Explain physically. This flow chart is a predetermined cycle
It is repeatedly executed in time. First, in step S1,
Power mode selection signal SP and engine torque T_E,motor
Torque T _M, Accelerator operation amount θ_A,Engine RPM
N_E, Motor speed N_M, Output speed N_O, Storage amount SO
A signal representing various information such as C is read. Step S2
Is executed by the power mode limiting means 40,
The power mode is selected by operating the power mode selection switch 28.
It is determined whether or not the selection signal SP is supplied, and the power
If the mode selection signal SP is supplied, step S
3 or less is executed, but the power mode selection signal SP is supplied
If not, step S8 and subsequent steps are executed.

After step S8, that is, step S8
Steps S12 to S12 are executed by the normal traveling control means 34. First, in step S8, it is determined whether or not the stored amount SOC is equal to or more than a predetermined constant amount A. The fixed amount A is
For example, it is the minimum required amount of electricity that can be driven by using the electric motor 14 as a power source without significantly impairing charging efficiency and discharging efficiency. Then, if SOC ≧ A, step S9 and subsequent steps are executed, but if SOC <A, the charge mode subroutine of step S7 is executed. Step S9 is executed by the first calculating means 46 and the second calculating means 48, and the fuel consumption amounts Mfc _m , M are calculated according to the equations (1) and (2).
Calculate fc _e . Step S10 is executed by the comparison means 50 and compares the fuel consumption amounts Mfc _m and Mfc _e to select the smaller traveling mode. That is, Mfc
_{If e} <Mfc _m , the motor drive subroutine of step S11 is executed, and while traveling in the motor drive mode using the electric motor 14 as a power source, if Mfc _e > Mfc _m , the ICE drive subroutine of step S12 is executed. Since the vehicle travels in the ICE drive mode in which the internal combustion engine 12 is used as a power source, the internal combustion engine 12 and the electric motor 14 are selectively used so that the fuel consumption amount Mfc is minimized. If Mfc _e = Mfc _m , any one may be selected,
In this embodiment, the ICE drive mode is selected.

If the determination in step S2 is YES,
That is, the step S3 executed when the power mode selection signal SP is supplied is executed by the power mode prohibiting means 42, and whether or not the stored amount SOC is equal to or more than a predetermined constant amount A as in the case of the step S8. When the SOC is equal to or more than the predetermined amount A, steps S4 and below are executed, but when SOC <A, steps S6 and below are executed.
Step S4 is executed by the power / normal switching means 44, and if the instantaneous travel required power P _L is equal to or greater than a preset constant value B, the ICE / motor drive subroutine of step S5 is executed, but P _L <B In this case, step S9 and subsequent steps are executed. The ICE / motor drive subroutine of step S5 is executed by the power running control means 36, for example, the internal combustion engine 12 is operated at the maximum output, and the electric motor 14 is assisted to perform the power mode running.

If the determination in step S3 is NO, that is, step S6, which is executed when SOC <A, is executed by the power mode prohibiting means 42, and the power mode disable signal SD is output to the power mode disable display 30. Visually indicates that power mode driving is not possible. The charge mode subroutine of the next step S7 is the IC
This is executed by the E drive / charge traveling control means 38, and the charging mode traveling is performed in accordance with the flowchart of FIG. In step R1 in FIG. 6, the first time to set the instantaneous required drive power P _L as the engine output (power) P _ICE is,
After the second time, the engine output P _ICE is increased by a predetermined change amount ΔP _ICE . In this case, the engine speed N _E is set constant according to the operating state (vehicle speed), so the engine torque T _E is increased as shown in FIG. 9 corresponding to the change amount ΔP _ICE , and the change amount is changed. ΔP _ICE total, that is, engine output P _ICE and power required for instantaneous driving P
The difference from _L (P _ICE −P _L ) is the surplus power. FIG. 9 shows constant power lines, and even if the power is the same, the engine speed N _E
Although the engine torque T _E differs depending on the engine torque P _E , the engine output P _ICE and the power required for instantaneous travel P _L are set by the relationship between the engine speed N _E and the engine torque T _E which are determined by the operating conditions. The change amount ΔP _ICE may be set to a fixed amount in advance, or may be set based on a data map or the like in accordance with the operating state of the momentary travel required power P _L or the like. Further, the engine torque T _E may be changed by a predetermined amount.

At step R2, the engine output P
_The fuel consumption efficiency η _ICE is calculated from the data map of FIG. 7 and the like according to the _ICE , and in step R3, the surplus power (P
_ICE- P _L ) is used to rotate the electric motor 14 to charge the electric motor 14, and the efficiency η _T of the entire system regarding fuel consumption is calculated by the following equation.
Calculate and store according to (3). In this embodiment, after the electric motor 14 is rotationally driven by the surplus power (P _ICE −P _L ) to charge the electric storage device 22 with electric energy,
The ratio of the fuel consumption amount Mfc to the output (power) of the electric motor 14 when the electric motor 14 is rotationally driven by the electric energy is obtained as the efficiency η _T of the entire system. _{η T = η GEN × η BIN} × η BOUT × η MOT × η ICE + (P L / P ICE) × η ICE × (1-η GEN × η BIN × η BOUT × η MOT) ··· (3)

Power generation efficiency η in the above equation (3)_GENIs before
Based on a data map or the like stored in the storage means 52
The margin power (P_ICE−P_L) That is, the rotation speed and
And the torque required for regenerative braking (regenerative braking torque)
Electric efficiency η_BINIs the date stored in the storage means 52.
The surplus power (P_ICE−P_L)
And the amount of stored electricity SOC. Discharge efficiency η_BOUT
And drive efficiency η_MOTIs in the motor drive mode
Learning value, which is used for example in the motor drive mode running in the past.
Average value at the time of running (moving average, etc.) or last motor
Stores the instantaneous value, etc. when driving in the drive mode in the storage means 52, etc.
Then, use that value. Discharge efficiency η _BOUTIs a memory hand
Based on the data map stored in the column 52,
Momentary power required for moment P_LAnd depending on the stored amount SOC
Required, drive efficiency η_MOTIs stored in the storage means 52
Based on the data map etc._L
That is, the motor speed N_MAnd motor torque T_MIn response
Will be asked for.

In the next step R4, the engine output P
_ICEIs the predetermined value P_EThe predetermined value P is determined by determining whether or not_E
Execution of step R1 and subsequent steps is repeated until the value exceeds. Place
Fixed value P _EMay be set to a fixed value in advance, but
Necessary power P_LInternal combustion engine 12 or electric motor according to
In the data map, etc., so that 14 does not overrun
Therefore, it can be set. Step R
1 to R4 are surplus power (P_ICE−P_L) By electric energy
Electric motor 14 for charging the electricity storage device 22 with ruggie
Power generation efficiency η_GENAnd charging efficiency η of power storage device 22_BIN
Efficiency η of fuel consumption considering fuel consumption
_TThe marginal power (P_ICE−P_L) While changing
It corresponds to the calculation means for the next calculation. In this example, the storage
After charging the power storage device 22, the power is further charged from the power storage device 22.
The energy of the air is taken out and the electric motor 14 is used as the power source.
I want the overall efficiency of traveling in
You may just ask for the efficiency before charging.

At step R5, it is obtained at step R3.
Overall system efficiency η_TIs the maximum, that is, surplus power (P
_ICE−P_L) To charge the electric storage device 22 with electric energy
The electric energy causes the electric motor 14 to rotate.
The output (power) of the electric motor 14 when driven to rotate
Engine output with the lowest ratio of fuel consumption Mfc
Power P_ICESelect The discharge efficiency η of the above equation (3)_BOUTAnd
And drive efficiency η_MOTIs the engine output P_ICECommitted to the change of
Therefore, in step R5, the power storage device 22 is eventually
Consumption for the Charge of Electric Energy
Engine output P with the smallest proportion of amount Mfc_ICEIs selected
Will be. Then, in step R6, the
Engine power P_ICEWhen operating the internal combustion engine 12 with
To the electric power P of the electric motor 14_GENMargin power (P_ICE
−P_L), And the surplus power (P _ICE−P_L)In response to the
Set the regenerative braking torque. As a result,
Power storage device 2 in the state in which the ratio of fuel consumption Mfc
The vehicle is powered by the internal combustion engine 12 while charging 2
Can be run.

It should be noted that the power P _L required for the instantaneous traveling is the internal combustion engine 1
If the maximum output of 2 is exceeded, in the charging mode subroutine of step S7, the internal combustion engine 12 is operated at the maximum output and travels without regenerative braking of the electric motor 14. Also in the normal mode running of the step S9 or less, if the instantaneous required drive power P _L is greater executes the ICE driving subroutine of Step S12, exceeds the instantaneous required drive power P _L which case the maximum output of the internal combustion engine 12 However, the vehicle runs at the maximum output of the internal combustion engine 12. When the power mode selection switch 28 also serves as the shift pattern selection switch of the transmission 16, the power performance-oriented shift control is performed regardless of whether or not the power mode traveling is possible.

Here, the drive control device 10 of this embodiment is
The power mode running is not performed unless the power mode selection switch 28 is operated, and the vehicle is run in the normal mode using either one of the internal combustion engine 12 and the electric motor 14 as a power source.
Is less than a certain amount A, the operation of the electric motor 14 is limited, and when the charge mode subroutine of step S7 is executed, the internal combustion engine 12 is used as a power source to drive the vehicle so that the maximum amount is adjusted according to the driver's intention. The drive torque can be generated, and the driver does not feel uncomfortable.

Further, when the amount SOC of electricity stored in the electricity storage device 22 is less than the constant amount A, the determination in step S3 becomes NO, and regardless of the operation of the power mode selection switch 28, execution of step S5 becomes impossible and power mode running is performed. Is prohibited, the amount of stored electricity SOC becomes too small and the electricity storage device 22
Damage to the vehicle and a significant decrease in the charging efficiency η _BIN and the discharging efficiency η _BOUT are avoided, while the power mode disabled indicator 30 informs the driver that the power mode cannot be run. The driver does not feel uncomfortable due to insufficient driving force due to the stop of the operation of 14.

Although one embodiment of the present invention has been described in detail with reference to the drawings, the present invention can be implemented in other modes.

For example, in the above embodiment, the fuel consumption amount Mf
Although the power transmission efficiency of the transmission 16 is not taken into consideration when calculating _cm , Mfc _e and the efficiency η _T of the entire system, if the gear ratio can be changed steplessly or continuously, the power transmission can be performed by the gear ratio. The efficiency is different, and the fuel consumption Mfc _m , M
Since fc _e and the efficiency η _{T of the} entire system also change, it is desirable to use the power transmission efficiency of the transmission 16 to obtain them according to the following equations (4) to (6). Equations (4) to (6) are for the case where the transmission 16 is a continuously variable transmission (CVT), and the power transmission efficiency η _CVT is data having parameters such as the gear ratio, the transmission torque, and the rotation speed of the input / output member. Power transmission efficiency η _CVT obtained from maps, etc.
The data (which may be an arithmetic expression or the like) necessary for the calculation of is stored in the storage unit 52 in advance. _{Mfc m = FC m × P L} / η CVT ··· (4) Mfc e = FC e × P L / (η GEN × η BIN × η BOUT × η MOT × η CVT) ··· (5) η T _{= η GEN × η BIN × η} BOUT × η MOT × η CVT * × η ICE + (P L / P ICE) × η ICE × {1- (η GEN × η BIN × η BOUT × η MOT × η CVT * ) / Η _CVT } (6)

Power transmission efficiency η of the above equations (4) to (6)
_CVT is the present operating condition, that is, the power P _L required for instantaneous travel.
Depending on the transmission torque and the gear ratio depending on the
Obtained from such stored data map, the (6) power transmission efficiency eta _CVT ^* is the discharge efficiency eta _BOUT and driving efficiency eta
_{As in the case of MOT} , the learning value during traveling in the motor drive mode is used. As the learning value, for example, the average value (moving average, etc.) during the motor drive mode traveling performed in the past, the instantaneous value during the last motor drive mode traveling, or the like may be stored in the storage means 52 or the like. Good.

Further, in the above-described embodiment, one of the internal combustion engine 12 and the electric motor 14 having the smaller fuel consumption amount Mfc is used for traveling, and the charging mode is set in a state in which the efficiency η _{T of the} entire system regarding fuel consumption is maximized. The vehicle is designed to run, and the exhaust gas amount is also reduced as the fuel consumption amount Mfc is reduced, but the fuel consumption rates FC _m and FC _e of the equations (1) to (6) are Instead, use the exhaust gas rate (exhaust gas amount per unit power), fuel consumption efficiency η
It is possible to further reduce the amount of exhaust gas by using exhaust gas efficiency (reciprocal of exhaust gas rate) instead of _ICE . It is also possible to selectively use the internal combustion engine 12 and the electric motor 14 or set the engine output P _ICE during the power generation mode drive based on the physical quantity of the internal combustion engine 12 other than the fuel consumption amount Mfc and the exhaust gas amount. is there.

In the above embodiment, the power P required for instantaneous running is
Fuel consumption Mfc _m , Mfc one by one according to operating conditions such as _{L
Although e} was calculated, the energy conversion efficiencies η _GEN and η _MOT of the electric motor 14 were about 92% at the maximum (η _MOTmax portion in FIG. 8), and the input / output efficiency η _{BIN of the} power storage device 22 was calculated.
× η _BOUT is about 85%, and the energy conversion efficiency of the entire electric system is about 0.92 × 0.85 × 0.92≈0.72. Therefore, for example, when traveling with the internal combustion engine 12 as the power source. fuel consumption efficiency eta _ICE of internal combustion engine 12, with up to 70% of the boundary conditions of the fuel consumption efficiency η _{ICEmax 0.7η ICEm ax} greater than when the internal combustion engine 12, as shown in FIG. 7, the boundary conditions 0.7η _ICEmax If smaller, the electric motor 14 may be used. Maximum fuel consumption efficiency η
_{The ratio} of the boundary condition to _ICEmax may be set appropriately according to the energy conversion efficiency of the electric motor 14 and the power storage device 22.

Further, in step R1 of FIG.
Output P_ICEMomentary required power P _LInitialize to
Change amount ΔP_ICEWas gradually increasing
Is, for example, the minimum fuel consumption rate line L shown by the one-dot chain line in FIG.
Engine output P with a specified torque width between the top and bottom_ICEStrange
The efficiency of the entire system η_TIs the maximum
Engine output P_ICEThe method of searching for
You.

In addition, the method for determining whether to execute the motor drive mode or the ICE drive mode during the normal mode traveling after step S8, and the engine output P _ICE and the generated power P in the charge mode subroutine of step S7.
_{The GEN} setting method can be appropriately changed.

In the above embodiment, if the determination in step S8 is NO, the power mode disable display is not performed, but step S6 may be executed to perform the power mode disable display. In that case. The SOC determination may be performed prior to step S2.

Although the electric motor 14 also serves as a generator in the above-described embodiment, a generator may be provided separately from the electric motor 14.

In the above embodiment, the electric motor 14 is 1
However, the present invention can be applied to various hybrid vehicles, such as one having an electric motor 14 for each drive wheel.

Although not individually exemplified, the present invention can be carried out in various modified and improved modes based on the knowledge of those skilled in the art.

[Brief description of drawings]

FIG. 1 is a block diagram illustrating a configuration of a drive control device for a hybrid vehicle that is an embodiment of the present invention.

FIG. 2 is a diagram showing a specific example of a transmission and a vehicle drive output device in the drive control device of FIG.

3 is a block diagram illustrating a part of a function of a controller in the drive control device in FIG. 1. FIG.

FIG. 4 is a block diagram illustrating the contents of normal traveling control means of FIG.

FIG. 5 is a flowchart illustrating an operation when switching the traveling mode in the drive control device of FIG.

FIG. 6 is a flowchart for specifically explaining the charging mode subroutine of FIG.

FIG. 7 is a diagram illustrating an example of fuel consumption efficiency of the internal combustion engine in the drive control device of FIG. 1.

8 is a diagram illustrating an example of energy conversion efficiency of an electric motor in the drive control device of FIG.

9 is an engine output P in the flowchart of FIG.
It is a diagram illustrating the relationship between the _ICE and the margin power (P _ICE -P _L).

[Explanation of symbols]

10: Drive control device 12: Internal combustion engine (engine) 14: Electric motor 22: Power storage device 28: Power mode selection switch (power mode selection means) 30: Power mode disable indicator (power mode disable display means) 40: Power mode Limiting means 42: Power mode prohibiting means

Claims (3)

[Claims] 1. An engine that operates by combustion of fuel and an electric motor that operates by electric energy stored in a power storage device are provided as power sources when the vehicle is running, and only one of the engine and the electric motor is provided. In a hybrid vehicle capable of running in a normal mode capable of running with a maximum torque by operating the engine and a power mode running in which a driving force of both the engine and the electric motor is added at a maximum torque, the power mode running And a power mode limiting means for permitting the power mode running when the power mode selecting means is operated, but for prohibiting the power mode running when the power mode selecting means is not operated. And a drive control device for a hybrid vehicle. 2. The drive control device for a hybrid vehicle according to claim 1, further comprising means for setting a normal mode traveling when the power mode selection means is not operated. 3. When the amount of electricity stored in the electricity storage device is smaller than a predetermined value, the power mode traveling is prohibited in preference to the operation of the power mode selecting means, and only the engine is used as a power source. The hybrid vehicle according to claim 1, further comprising: prohibiting means and power mode prohibiting display means for notifying a driver of the fact that the power mode traveling is prohibited by the power mode prohibiting means. Drive controller.