JP2000287304A - Drive device for internal combustion engine - Google Patents

Abstract

[PROBLEMS] To increase a fuel cut area at the time of deceleration or braking and to drive an electric motor with electric power obtained by regeneration during idling to reduce fuel consumption. SOLUTION: When starting, an inverter 1 is connected to a battery 15.
In the internal combustion engine drive device, which supplies power to the motor generator 3 via the motor generator 3 to start the engine 1 and charges the battery 15 with the power generated by the motor generator 3 during normal traveling, the engine 1 is driven during deceleration or braking.
Cuts the fuel supply to the motor generator 3
When the rotation speed of the internal combustion engine falls below the target idle speed, power is supplied from the battery 15 to the motor generator 3 so as to maintain the target idle speed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving apparatus for an internal combustion engine, and more particularly to an improvement in a driving apparatus for a vehicle having an internal combustion engine and an electric motor as power sources.

[0002]

2. Description of the Related Art Conventionally, as a driving device for an internal combustion engine of this type, there has been proposed, for example, Japanese Patent Application Laid-Open No. Hei 5-260610.

This drive device for an internal combustion engine converts electric energy bidirectionally between an electric motor connected to a drive shaft of the internal combustion engine, a power storage device, and an AC circuit of the electric motor and a DC circuit of the power storage device. And an inverter control circuit for controlling the inverter circuit, and a control circuit for controlling the torque of the electric motor. When the vehicle is accelerating, power is supplied from the power storage device to the electric motor to output the internal combustion engine. It assists, stops fuel supply to the internal combustion engine during deceleration or braking, performs regenerative braking using the electric motor as a generator, and charges the power storage device with the generated power.

[0004] A conventional drive system for an internal combustion engine recovers the kinetic energy of the vehicle as electric energy at the time of deceleration or braking as described above, and uses this to improve the acceleration performance of the vehicle at the time of acceleration or the like. The fuel consumption of the internal combustion engine is reduced.

[0005]

However, in the above-mentioned conventional internal combustion engine driving apparatus, the engine speed is lower than the target idle speed at the time of fuel cut recovery in which the supply of fuel is restarted as the deceleration or braking is completed. If the engine speed drops below a predetermined speed higher than the target idle speed at the time of deceleration or braking, fuel supply is restarted so as to prevent a stall that decreases, so that fuel cut recovery during gradual deceleration is performed. There is a problem that the fuel supply is sometimes restarted earlier than necessary, which leads to an increase in fuel efficiency and a deterioration in exhaust emission.

Another problem is that fuel consumption during idling cannot be eliminated because idling is maintained by the internal combustion engine.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is possible to enlarge a fuel cut region in which fuel supply is stopped during deceleration or braking, and to regenerate during idling. It is an object of the present invention to drive an electric motor with reduced electric power to save fuel consumption, and to reduce fuel consumption by performing idle stop when a stop condition is satisfied.

Further, by maintaining idle rotation by the electric motor until a clear stop condition is established, even if the vehicle suddenly starts halfway up to that point, smooth acceleration can be achieved without any backlash, which makes the driver feel uncomfortable. The purpose is to avoid shock.

[0009]

According to a first aspect of the present invention, there is provided a motor generator connected to a drive shaft of an internal combustion engine, outputting AC power of the motor generator as predetermined DC power, and converting DC power to AC power. An inverter capable of conversion and a power storage device connected to the inverter, the power storage device supplies power to the motor generator at the time of starting to start the internal combustion engine, and stores the power generated by the motor generator during normal driving. In the internal combustion engine drive device, the fuel supply to the internal combustion engine is cut at the time of deceleration or braking, and power is generated by regenerative braking by the motor generator. Control is performed by supplying power from the device to maintain the target idle speed.

According to a second aspect of the present invention, the throttle valve provided on the intake side of the internal combustion engine is opened when power is supplied to the motor generator and the target idle speed is maintained. It is characterized by controlling.

[0011] The invention of claim 3 is claim 1 or claim 2.
In the invention, the output shafts of the internal combustion engine and the motor generator are provided with clutch means capable of connecting and disconnecting the input shafts thereof, and the output shafts of the internal combustion engine and the motor generator and the clutch means are provided at least up to the target idle speed during deceleration or braking. Is controlled to release the direct connection state of the input shaft.

According to a fourth aspect of the present invention, there is provided the first or second aspect.
In the invention, an output shaft of the internal combustion engine and the motor generator is provided with clutch means capable of connecting and disconnecting an input shaft thereof, and a sensor means for detecting disconnection thereof, and the input shaft of the internal combustion engine and the motor generator is connected to the input shaft. When the shaft is shut off, power is supplied to the motor generator to control the motor to maintain the target idle speed.

According to a fifth aspect of the present invention, there is provided the first to fourth aspects.
In the invention of the third aspect, only when the air conditioner is turned off, power is supplied to the motor generator to control to maintain the target idle speed.

According to a sixth aspect of the present invention, there is provided the first to fifth aspects.
According to the invention, when the power is supplied to the motor generator to maintain the target idle speed, the motor generator is controlled to stop when a predetermined stop condition is satisfied.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 Hereinafter, a drive device for an internal combustion engine according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a configuration diagram showing a drive device of an internal combustion engine by a motor generator using an inverter according to Embodiment 1 of the present invention.

In FIG. 1, an engine 1 which is an internal combustion engine
Is connected to a motor generator 3, and a clutch 5, a transmission 7, a gear device 9, and wheels 11 are sequentially connected to the motor generator 3 via a rotating shaft. The motor generator 3 is connected with an inverter 13 that converts AC power from the motor generator 3 into DC power and converts a DC voltage into an AC voltage and supplies the AC voltage to the motor generator 3. Further, a battery 15 as a power storage means is connected to the inverter 13.

The engine 1 generates an engine output, and drives the motor generator 3 as a generator using the engine output. The drive output of the engine 1 is transmitted to the wheels 11 via the clutch 5, the transmission 7, and the gear device 9 to drive the vehicle.

The motor generator 3 is a rotating machine that functions as a generator or a motor, and its rotor is directly connected to the crankshaft of the engine 1. When functioning as a generator, the motor generator 3 is driven by the engine output as described above to generate power. On the other hand, during regenerative braking, the braking energy is regenerated and the generated power is stored in the battery 15. In addition, when functioning as a motor, the vehicle rotates by power supply from the battery 15, and the wheels 11 are driven by the rotational force to run the vehicle. Further, the motor generator 3 performs cranking of the engine by functioning as a motor when the engine is started.

The inverter 13 is a power conversion device, which converts AC power generated by the motor generator 3 into DC power by switching a switching element, and converts DC power from the battery 15 into AC power for driving the motor. It is configured to convert. A voltage sensor is attached to the battery 15, and a voltage value detected by the voltage sensor is output to a controller 17 described later.

The transmission 7 and the clutch 5 of this embodiment are of a hydraulic control type. As the control oil pressure of both configurations, for example, the oil pressure generated by the same oil pressure generating means (not shown) is used, and the oil pressure generating means is driven by the output of the engine. The transmission 7 includes a gear position detecting device 2.
0 is attached, and a signal detected by the gear position detection device 20 is output to a controller 17 described later.

The clutch 5 is configured so that its input shaft can be connected to and disconnected from the output shaft of the motor generator 3. The connection state between the output shaft of the motor generator 3 and the input shaft of the clutch 5 is controlled by a signal from a controller 17 described later. Is controlled. The clutch 5 is provided with a sensor (not shown) for detecting the connection state, and an output signal of this sensor is input to a controller 17 described later.

The above is the description of the configuration of the vehicle driving apparatus using the motor generator using the inverter according to the present embodiment.

Next, the operation of the vehicle drive device according to the first embodiment will be described. The drive device of this vehicle has a controller 17 shown in FIG.
The vehicle speed, the brake operation state, the accelerator operation state, the gear setting state, and the voltage value of the battery 15 are input to. The controller 17 is configured to output control signals to the engine 1, the inverter 13, the clutch 5, and the transmission 7. The controller 17 includes a central processing unit (CPU) and a storage unit (RA
M, ROM), an input / output interface, and other components, and can be configured using the same components as those used in an electronic control unit (ECU) for controlling each component of the vehicle. . Hereinafter, the control contents of the controller 17 will be described.

In the flowchart of FIG. 2, the case where the rotation speed of the engine 1 has already been reduced and reduced when the vehicle stops running at a constant speed will be described as an example. In this case, the driver releases the accelerator pedal to set the accelerator opening = 0, and the brake pedal is depressed.

First, at step 100, the controller 1 determines whether or not the vehicle is decelerating or braking based on the operation states of the accelerator pedal and the brake pedal. If it is determined that the vehicle is decelerating or braking, the process proceeds to step 300 to decelerate or brake. Execute the processing routine at the time.

On the other hand, if it is determined in step 100 that the vehicle is not decelerating or braking, the process proceeds to a routine for driving the engine. In steps 200 and 201, the engine is driven and the motor generator 3 is driven normally. Perform power generation processing.

In the processing routine at the time of deceleration or braking, first, at step 300, it is determined whether or not the engine speed is equal to or lower than the target idle speed based on the signal of the engine speed of the engine.

If the engine speed is equal to or lower than the target idle speed, the routine proceeds to step 301, where it is determined whether the clutch 5 is disconnected.

If the clutch 5 is disconnected, the routine proceeds to step 302, where it is determined whether the air conditioner is off.

If the air conditioner is off, step 303
Then, power is supplied to the motor generator 3 from the battery 15 serving as power storage means via the inverter 13 to generate driving torque, and the target idle speed is set against the friction of the engine 1 and the automatic transmission 3. maintain.

In this case, the throttle valve in step 304 is controlled to be open so that the pump loss of the engine is reduced and the power consumption of the motor generator 3 is reduced.

On the other hand, if the engine speed is higher than the target idle speed at step 300,
Proceeding to 401, regenerative braking and fuel cut according to the state of the battery 15 are performed. That is, step 400
Then, power is generated by regenerative braking by the motor generator 3,
The generated power is stored in the battery 15 via the inverter 13. In step 401, the fuel supply to the internal combustion engine is cut.

FIG. 3 is a graph showing the above control operation.
FIG. 5 is an explanatory diagram showing a relationship between an engine speed and a motor generator torque with an abscissa as a time axis, taking an automatic transmission vehicle as an example. In this graph, at the time of deceleration and braking of the vehicle, until the engine speed reaches the target idle speed, the motor generator 3 functions as a generator, regenerates braking energy and stores the generated power in the battery 15. I do. Then, at the same time when the engine speed reaches the target idle speed, the torque of the motor generator 3 switches from negative to positive and a driving force is generated, so that the engine speed is maintained at the target idle speed.

Thereafter, if a predetermined stop condition is satisfied in step 500, the motor generator 3 is stopped in step 501.

The conditions for stopping the vehicle include, for example, (A) "the vehicle is stopped" (B) "the SOC value indicating the charged amount of the battery 15 is equal to or more than a predetermined value" (C) "the brake is ON" State "(D)" The gear position of the transmission is set from neutral to neutral. "

If the predetermined starting condition is satisfied in step 600, the motor generator 3 is restarted.

The conditions for restarting are, for example, (E) “the SOC value indicating the charged amount of the battery 15 is equal to or less than a predetermined value” (F) “the accelerator is ON” (G) “the brake is OFF” ( H) "The gear position of the transmission is set from neutral to other than neutral".

As described above, according to this embodiment, the motor generator 3 is driven by supplying power to the motor generator 3 while the fuel supply from the injector is cut while switching from deceleration or braking to idle rotation. Thus, the fuel cut at the time of deceleration or braking can be continued as it is, the fuel cut area at the time of deceleration can be maximized, the fuel consumption can be reduced, and the exhaust emission can be improved. Then, during idling, the motor generator is driven by the electric power obtained by regeneration, thereby making it possible to reduce fuel consumption.

Further, since the throttle valve is controlled to be opened during idling by the motor generator 3, the pump loss of the engine is reduced, the power consumption of the motor generator is reduced, the fuel consumption is reduced, and the exhaust emission is improved.

Further, by supplying power to the motor generator when the clutch is disengaged and maintaining the target idle speed, the engine is controlled to stop when the clutch is directly connected, so that the driver feels uncomfortable. Can be prevented.

Further, since the power is supplied to the motor generator when the air conditioner is turned off to maintain the target idle speed, the comfort of the driver in the vehicle can be ensured.

Further, since the motor generator is stopped when a clear stop condition is satisfied, smooth acceleration is possible without any backlash even in the case of a sudden start occurring halfway up to that time, and the driver feels uncomfortable. It has the effect of not giving a shock.

Embodiment 2 In the second embodiment, the output shaft of the engine 1 and the clutch before the engine speed at the time of deceleration or braking decreases to the target idle speed in the first embodiment (particularly, the drive device of an AT (automatic) vehicle). 5 is configured to release the direct connection state of the input shaft.

As described above, according to the second embodiment, particularly in a drive device of an AT (automatic) vehicle, the direct connection between the output shaft of the internal combustion engine and the input shaft of the clutch means is released at least up to the target idle speed. By doing
The load on the motor generator can be reduced.

[0045]

According to the first aspect of the present invention, the fuel supply to the internal combustion engine is cut at the time of deceleration or braking, and power is generated by regenerative braking by the motor generator. When the rotation speed of the internal combustion engine becomes lower than the target idle rotation speed. Since the power is supplied to the motor generator so as to maintain the target idle speed, the fuel cut region can be expanded during deceleration or braking.

According to the second aspect of the present invention, the throttle valve provided on the intake side of the internal combustion engine is controlled to be open when the target idle speed is maintained by supplying power to the motor generator. The pump loss of the motor generator is reduced, the power consumption of the motor generator is reduced, the fuel consumption is reduced, and the exhaust emission is improved.

According to the third aspect of the present invention, in particular, in a drive device of an AT (automatic) vehicle, the direct connection between the output shaft of the internal combustion engine and the input shaft of the clutch means is released at least up to the target idle speed. The load on the motor generator can be reduced.

According to the fourth aspect of the present invention, in the driving apparatus for an MT (manual) vehicle, when the output shaft of the internal combustion engine and the input shaft of the clutch means are cut off, electric power is supplied to the motor generator to achieve the target idle rotation. By maintaining the number, when the clutch is directly connected, the engine is also controlled to stop, so that it is possible to prevent the driver from feeling uncomfortable.

According to the invention of claim 5, the OF of the air conditioner is
Power is supplied to the motor generator only at the time of F to maintain the target idle speed, so that the comfort of the driver in the vehicle can be ensured.

According to the sixth aspect of the present invention, when power is supplied to the motor generator and the target idle speed is maintained, the motor generator is stopped when a clear predetermined stop condition is satisfied. Therefore, even in the case of a sudden start occurring halfway up to that time, smooth acceleration is possible without any backlash, and there is an effect that the driver does not feel discomfort and shock.

As described above, according to the present invention, the fuel cut region in which the supply of fuel is stopped at the time of deceleration or braking is expanded, and during idling, the motor is driven by the electric power obtained by regeneration and the fuel is cut off. It is possible to reduce fuel consumption and idle stop when the stop condition is satisfied, thereby reducing fuel consumption. In this way, it is possible to configure a drive device for an internal combustion engine that can achieve improved fuel efficiency while providing the operability, safety, and responsiveness of the vehicle required by the driver.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a drive device of an internal combustion engine by a motor generator using an inverter according to a first embodiment of the present invention.

FIG. 2 is a flowchart illustrating a control operation of the drive device for the internal combustion engine according to the first embodiment of the present invention.

FIG. 3 is a diagram for explaining a control operation of the vehicle drive device according to the first embodiment of the present invention.

[Explanation of symbols]

1 engine, 3 motor generator, 5 clutch, 7 transmission, 13 inverter, 15 battery, 1
7 Controller.

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masakazu Nakayama 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Electric Corporation In-house F-term (reference) 3D039 AA01 AA02 AA04 AB27 AC02 AC33 AD01 AD06 AD22 AD44 AD53 3G093 AA05 AA07 AA16 BA22 CA04 CB07 DA01 DA06 DB05 DB10 DB11 DB15 DB19 DB25 EA05 EA09 EB00 EB02 EC02 FB02 5H115 PA01 PA12 PI16 PI29 PI30 PO17 PU08 PU22 PU23 PU25 PU29 PV09 QA01 QE10 QH02 QI04 QN03 RB08 SE04

Claims (6)

[Claims] 1. A motor generator connected to a drive shaft of an internal combustion engine, an inverter that outputs AC power of the motor generator as predetermined DC power and can convert DC power to AC power, and is connected to the inverter. A drive device for the internal combustion engine that supplies power to the motor generator from the power storage device at startup to start the internal combustion engine and charges the power storage device with power generated by the motor generator during normal driving. Alternatively, the fuel supply to the internal combustion engine is cut during braking, and power is generated by regenerative braking by the motor generator. When the rotation speed of the internal combustion engine falls below the target idle rotation speed, power is supplied from the power storage device to the motor generator to set the target idle rotation speed. A driving device for an internal combustion engine, wherein the driving is controlled so as to maintain the following. 2. The throttle valve provided on the intake side of the internal combustion engine is controlled to be open when power is supplied to the motor generator and the target idle speed is maintained. A drive device for an internal combustion engine according to claim 1. 3. An output shaft of the internal combustion engine and the motor generator is provided with a clutch means capable of connecting and disconnecting an input shaft thereof, and the output of the internal combustion engine and the motor generator is reduced at least up to a target idle speed during deceleration or braking. The drive device for an internal combustion engine according to claim 1 or 2, wherein control is performed to release a direct connection state between the shaft and an input shaft of the clutch means. 4. An output shaft of the internal combustion engine and the motor generator, wherein the output shaft of the internal combustion engine and the motor generator is provided with a clutch means capable of connecting and disconnecting an input shaft of the internal combustion engine and a motor generator. 3. The internal combustion engine driving device according to claim 1, wherein when the input shaft of the means is shut off, the motor generator is controlled so as to maintain the target idle speed by supplying power to the motor generator. 5. The motor according to claim 1, wherein power is supplied to the motor generator only when the air conditioner is turned off so as to maintain the target idle speed.
The driving device for an internal combustion engine according to any one of claims 1 to 3. 6. The motor control device according to claim 1, wherein when power is supplied to the motor generator to maintain the target idle speed, the motor generator is stopped when a predetermined stop condition is satisfied. A drive device for an internal combustion engine according to claim 5.