JPH11210448A - Internal combustion engine controller for hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To securely prevent worsening of exhaust emission by providing a temperature hold means holding a temperature of an exhaust air purifying part for purifying exhaust air from an internal combustion engine above a function activation temperature. SOLUTION: This hybrid engine has a power distribution mechanism 4 distributing rotation force of an output shaft 1a of an internal combustion engine 1 to a power generator 3 and a rotary shaft 2a of an electric motor 2. Moreover, it is provided with an inverter 5 which selectively applies power generated by the power generator 3 to the electric motor 2 and a battery 6 or condensed power of the battery 6 to the electric motor 2. In this case, an exhaust air purifying catalyst 14 as an exhaust air purifying part is provided on the halfway of an exhaust pipe 13 to hold a temperature of the exhaust air purifying catalyst 14 above a function activation temperature at all times irrespective whether the internal combustion engine is in an operation state or a non-operation state. That is, a catalyst temperature sensor 15 is provided to operate a heating means so that a temperature of the exhaust air purifying catalyst 14 is held above the function activation temperature when the temperature detected by the sensor 15 is dropping.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a technique for controlling an internal combustion engine of a hybrid vehicle having two driving sources, an internal combustion engine and an electric motor.

[0002]

2. Description of the Related Art In recent years, automobiles and the like have been required to reduce fuel consumption of an internal combustion engine and to purify exhaust gas discharged from the internal combustion engine. The development of a hybrid vehicle having two drive sources is underway.

[0003] As a hybrid vehicle as described above,
An internal combustion engine, a generator driven by the driving force of the internal combustion engine,
A battery that stores power generated by the generator, a motor driven by the power of the generator or the battery, and a power distribution mechanism that selectively distributes the driving force of the internal combustion engine to the generator and the wheels. There is known an apparatus that controls start and stop of an internal combustion engine in accordance with a driving force to be performed and a charged amount of a battery.

In this hybrid vehicle, when the vehicle starts or when the load is low, the transmission of the driving force from the internal combustion engine to the generator and the wheels is stopped or the internal combustion engine is stopped, and battery power is applied to the electric motor. The wheels are driven by the driving force of the electric motor.

Subsequently, during normal running of the hybrid vehicle, the internal combustion engine is started, the driving force of the internal combustion engine is distributed to both the generator and the wheels, and the electric motor is driven by the electric power generated by the generator. Then, the driving force of the electric motor is transmitted to the wheels. In this case, the hybrid vehicle runs with the driving force of the internal combustion engine and the electric motor.

Further, the hybrid vehicle starts the internal combustion engine under a high load such as during acceleration, distributes the driving force of the internal combustion engine to the generator and the wheels, and converts the electric power generated by the generator into battery power. The electric motor is driven by the electric power obtained by adding the above, and the driving force of the electric motor is transmitted to the wheels. In this case, the hybrid vehicle travels with the driving force of the internal combustion engine and the electric motor in the same manner as during normal traveling, but the electric motor is supplied with battery power in addition to the electric power of the generator. It becomes larger than when driving.

In the hybrid vehicle, when the vehicle is decelerated or braked, the transmission of the driving force from the internal combustion engine to the generator and the wheels is stopped or the internal combustion engine is stopped, and the rotational force of the wheels is transmitted to the electric motor. To generate regenerative power,
The obtained power is stored in the battery.

When the charged amount of the battery falls below a predetermined value or the like, the hybrid vehicle starts the internal combustion engine, distributes the driving force of the internal combustion engine to the generator and the wheels, and generates the driving force from the generator. The power is distributed to the battery and the electric motor, and the battery is charged.

According to such a hybrid vehicle, the internal combustion engine can be operated efficiently, and the fuel consumption rate can be significantly reduced, and the amount of exhaust gas can be reduced and purified. By the way, in the hybrid vehicle as described above, the case where the start and stop of the internal combustion engine are repeated depending on the driving conditions, or the low load operation (for example, the idling operation) in which the exhaust gas temperature becomes low even when the internal combustion engine is in operation, is long. For example, when the time is continued, the exhaust gas purifying components such as the exhaust gas purifying catalyst and the air-fuel ratio sensor tend to drop below the activation temperature. When the operation of the internal combustion engine is performed in a state where the exhaust gas purification component drops below the activation temperature, the exhaust purification catalyst NO _X in the exhaust gas, CO,
HC and the like cannot be sufficiently purified, resulting in deterioration of exhaust emission.

In order to solve such a problem, a control apparatus for an engine-driven generator of a hybrid vehicle disclosed in Japanese Patent Application Laid-Open No. 5-328528 is known. This device increases the exhaust temperature by controlling the engine output and the engine speed so as to deteriorate the energy efficiency of the internal combustion engine when the exhaust purification components such as the exhaust purification catalyst and the air-fuel ratio sensor are at a low temperature, The purpose is to increase the exhaust amount to a predetermined amount, complete the warm-up of the exhaust purification component early, and suppress deterioration of the exhaust emission.

[0011]

In the control device for an engine-driven generator of a hybrid vehicle as described above, during the period from the start of the internal combustion engine to the activation of the exhaust gas purification component, the exhaust gas generated by the exhaust gas purification component is activated. of NO _X, CO, can not purify HC and the like, there is a problem that the exhaust emission is deteriorated.

The present invention has been made in view of the above-mentioned problems, and in a hybrid vehicle including an internal combustion engine and an electric motor, the temperature of an exhaust purification component such as an exhaust purification catalyst is always maintained at a functional activation temperature or higher. The purpose of the present invention is to provide technology and prevent deterioration of exhaust emissions.

[0013]

The present invention employs the following means in order to solve the above-mentioned problems. That is,
An internal combustion engine control device for a hybrid vehicle according to the present invention includes an internal combustion engine, a generator driven by the internal combustion engine, a power storage unit that stores power generated by the generator, and the power generator or the power storage unit. An electric motor driven by electric power, and an engine control means for controlling the internal combustion engine in accordance with at least one of a driving state of the vehicle and a state of the power storage means, an internal combustion engine control device for a hybrid vehicle, It is characterized by comprising temperature maintaining means for maintaining the temperature of an exhaust gas purification component for purifying exhaust gas from the internal combustion engine at a function activation temperature or higher.

[0014] In the internal combustion engine control apparatus for a hybrid vehicle configured as described above, the temperature holding means always functions the temperature of the exhaust purification component regardless of whether the internal combustion engine is operating or stopped. Keep above activation temperature.

In this case, immediately after the internal combustion engine is started, or when a low-load operation (for example, an idling operation) in which the exhaust gas temperature becomes low continues for a long time, the exhaust gas purifying component is activated, and the exhaust gas is discharged from the internal combustion engine. The emission of exhaust gas does not deteriorate.

The above-mentioned temperature holding means comprises a temperature detecting means for detecting the temperature of the exhaust gas purifying component, and when the temperature detected by the temperature detecting means tends to decrease, the temperature of the exhaust gas purifying component is raised to a function activation temperature or higher. Temperature maintaining means for raising the temperature of the exhaust gas purifying component to maintain the temperature may be provided.

That is, the temperature holding means monitors the temperature of the exhaust gas purifying component, and when it is determined that the temperature of the exhaust gas purifying component is decreasing, the temperature of the exhaust gas purifying component is always higher than the functional activation temperature. The temperature of the exhaust purification component may be increased.

In this case, the temperature increasing means may be a means for forcibly starting the internal combustion engine via the engine control means, or a heating means for heating the exhaust purification parts.
Further, the temperature holding unit includes a storage amount detection unit that detects a storage amount of the storage unit, a temperature detection unit that detects a temperature of the exhaust purification unit, and a heating unit that heats the exhaust purification unit with the power stored in the storage unit. Means, the temperature detected by the temperature detection means is in a tendency to decrease, if the storage amount detected by the storage amount detection means is a predetermined value or more,
When the exhaust gas purification component is heated by the heating means, the temperature detected by the temperature detection means tends to decrease, and if the amount of power detected by the power storage amount detection means is less than a predetermined value, the engine control means The operating state of the internal combustion engine may be changed via the CPU.

That is, when the amount of power stored in the power storage means has a margin, the exhaust gas purification component is heated by the heating means, and when the amount of power stored in the power storage means has no margin, the operating state of the internal combustion engine is changed to change the exhaust gas purification component. May be maintained at or above the function activation temperature.

Here, as a method of changing the operating state of the internal combustion engine so as to maintain the exhaust purification component at or above the functional activation temperature, for example, when the internal combustion engine is stopped, the internal combustion engine is forcibly started and the exhaust gas is exhausted. Exhaust purification by increasing the exhaust temperature by controlling the exhaust gas purifying component by the heat above the function activation temperature, or by increasing the engine speed or load when the internal combustion engine is operating, or by retarding the ignition timing. A method of holding the component at or above the function activation temperature can be exemplified.

[0021]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an internal combustion engine control apparatus for a hybrid vehicle according to an embodiment of the present invention.

FIG. 1 is a diagram showing a schematic configuration of a hybrid mechanism of a hybrid vehicle to which the internal combustion engine control device of the present invention is applied. The hybrid mechanism includes: an internal combustion engine 1;
Engine output shaft (crankshaft) 1a of the internal combustion engine 1
A power distribution mechanism 4 connected to the generator 3 and distributing the torque of the engine output shaft 1a to the generator 3 and the rotation shaft 2a of the electric motor 2;
An inverter 5 for selectively applying the electric power generated by the generator 3 to the electric motor 2 or the battery 6, or selectively applying the electric power stored in the battery 6 to the electric motor 2;
The electric motor 2 includes a speed reducer 7 that reduces the rotational force of the rotating shaft 2 a of the electric motor 2 and transmits the reduced rotational force to the drive shafts 8 and 9, and wheels 10 and 11 attached to the drive shafts 8 and 9.

Each cylinder 29 of the internal combustion engine 1 is provided with an ignition plug 25 for burning an air-fuel mixture, and connected to the exhaust branch pipe 12 and the intake branch pipe 20. The exhaust branch pipe 12 is connected to an exhaust pipe 13, and the exhaust pipe 13 is connected to a muffler (not shown). An exhaust gas purifying catalyst 14 is provided in the exhaust pipe 13 as an exhaust gas purifying part.
An air-fuel ratio sensor 27 that outputs an electric signal corresponding to the air-fuel ratio of the exhaust gas flowing in the exhaust pipe 13 is attached to the exhaust pipe 13 located further upstream.

As the exhaust purification catalyst 14, for example,
It can be used three-way catalyst and NO _X purification catalyst. For example, when a three-way catalyst is used as the exhaust purification catalyst 14,
The exhaust gas purification catalyst 14 has a predetermined temperature (for example, 300 C
If the air-fuel ratio of the exhaust gas flowing into the exhaust purification catalyst 14 is the stoichiometric air-fuel ratio, HC and CO in the exhaust gas are reacted with O ₂ in the exhaust gas so that H ₂ O and C are activated.
At the same time as oxidizing to O ₂ , NO _X in the exhaust gas is reacted with HC and CO in the exhaust gas to produce H ₂ O, CO ₂ ,
It can be reduced to N ₂ .

When the internal combustion engine 1 is a lean burn internal combustion engine, a direct injection internal combustion engine, or a diesel engine,
As the exhaust purification catalyst 14, a NO _X storage catalyst, a NO _X selective reduction catalyst, or the like may be used.

Subsequently, a catalyst temperature sensor 1 for outputting an electric signal corresponding to the bed temperature of the catalyst is provided to the exhaust purification catalyst 14.
5 and a catalyst heater 30 for heating the exhaust purification catalyst 14 by supplying a drive current.

The air-fuel ratio sensor 27 is composed of, for example, a zirconia type oxygen sensor and has a predetermined temperature (for example, 400 ° C.).
°) Activate above to output a voltage corresponding to the air-fuel ratio of the exhaust.

The air-fuel ratio sensor 27 includes an air-fuel ratio sensor temperature sensor 28 for outputting an electric signal corresponding to the temperature of the sensor section, and an air-fuel ratio sensor heater 31 for heating the sensor section by supplying a drive current. It is attached. still,
The temperature of the air-fuel ratio sensor 27 may be estimated from the resistance value of the heater 31 for the air-fuel ratio sensor.

The catalyst temperature sensor 15 and the air-fuel ratio sensor temperature sensor 28 realize the temperature detecting means according to the present invention, and the catalyst heater 30 and the air-fuel ratio sensor heater 31 correspond to the present invention. Such a heating means is realized.

On the other hand, the intake branch pipe 20 is connected to a surge tank 21.
2 are connected. Each branch pipe of the intake branch pipe 20 is provided with a fuel injection valve 2 such that its injection hole faces the intake port of each cylinder 29.
6 is attached. In the middle of the intake pipe 22, a throttle valve 19 for adjusting the flow rate of air flowing through the intake pipe 22 is provided.
And an actuator 19a composed of a motor for opening and closing the throttle valve 19 and the like.

Subsequently, the power distribution mechanism 4 is, for example,
The planetary gear is formed of a planetary gear, the planetary carrier of the planetary gear has a rotating shaft connected to the engine output shaft 1a, and a ring gear disposed outside the planetary carrier has a rotating shaft connected to the rotating shaft 2a. The rotation shaft of the sun gear disposed inside the planetary carrier is configured to be connected to the generator 3. The rotational force of the planetary carrier is transmitted to a ring gear and a sun gear via a pinion gear rotatably supported by the planetary carrier.

The generator 3 is constituted by an AC synchronous motor or the like, and realizes a power generating means according to the present invention. The battery 6 is configured by a nickel-metal hydride battery cell or the like, and implements a power storage unit according to the present invention. This battery 6 includes:
SO that outputs an electric signal corresponding to the charge amount of battery 6
The C meter 16 is attached. This SOC meter 16
Implements a charged amount detection unit according to the present invention.

The electric motor 2 is constituted by an AC synchronous motor or the like, and realizes the electric motor according to the present invention. And
The electric motor 2 rotationally drives the rotating shaft 2 a with the electric power generated by the generator 3 or the electric power output from the battery 6. In addition, the electric motor 2 operates the wheels 1 when the vehicle decelerates.
The regenerative power generation is performed using the fact that the torques of 0 and 11 are transmitted to the rotating shaft 2a via the drive shafts 8 and 9 and the speed reducer 7. The power generated by this regenerative power generation is stored in the battery 6 via the inverter 5.

The inverter 5 is, for example, a power conversion device configured by combining a plurality of power transistors. The inverter 5 controls the power transistors to apply the power generated by the generator 3 to the battery 6, 3
Of the electric power generated in the electric motor 2 to the electric motor 2 and the battery 6
Between the electric power stored in the electric motor 2 and the electric power regenerated by the electric motor 2 to the battery 6.

Here, the power generated by the generator 3 is AC, the power stored in the battery 6 is DC, and the driving power of the electric motor 2 and the power generated by regenerative power are AC. Therefore, the inverter 5 is connected to the generator 3
After converting the AC current generated by the DC current into a DC current, the DC current stored in the battery 6 is applied to the battery 6, the DC current stored in the battery 6 is converted into an AC current, then applied to the electric motor 2, and the AC current generated by the generator 3 Is converted to a DC current and then applied to the battery 6, and the AC current regenerated by the electric motor 2 is converted to a DC current and then applied to the battery 6.

The internal combustion engine 1 includes various sensors such as a water temperature sensor 17 for outputting an electric signal corresponding to the temperature of the cooling water and a crank position sensor 18 for detecting the number of revolutions of the engine output shaft 1a. It is attached.

The above-mentioned catalyst temperature sensor 15, water temperature sensor 17, crank position sensor 18, air-fuel ratio sensor 2
7. The air-fuel ratio sensor temperature sensor 28 is connected to an internal combustion engine control electronic control unit (E-ECU) 23 that implements the engine control means according to the present invention via electric wiring. -It is input to the ECU 23. Further, the ignition plug 25, the fuel injection valve 26, the actuator 19
a, catalyst heater 30, and air-fuel ratio sensor heater 31
Are also connected to the E-ECU 23 via electric wiring.

On the other hand, the electric motor 2, the generator 3,
The inverter 5 and the SOC meter 16 are connected via an electric wiring to an electronic control unit (H-ECU) 24 that integrally controls the hybrid mechanism.

The E-ECU 23 determines the operating state of the internal combustion engine 1 using the output signals from the various sensors as parameters, and according to the operating state, ignition timing, fuel injection time (fuel injection amount), fuel injection The timing, intake air amount, etc. are calculated. The E-ECU 23 controls the ignition plug 25, the fuel injection valve 26, the actuator 19a, and the like based on the calculated ignition timing, fuel injection time, fuel injection timing, intake air amount, and the like.

When controlling the fuel injection valve 26, the E
-The ECU 23 refers to the output signal value of the air-fuel ratio sensor 27 and performs feedback control so that the air-fuel ratio of the exhaust gas flowing into the exhaust purification catalyst 14 becomes a desired air-fuel ratio (for example, a stoichiometric air-fuel ratio).

On the other hand, the H-ECU 24 controls the generator 3 and the inverter 5 on the basis of the depression amount of an accelerator pedal (not shown) and the output signal of the SOC meter 16, and the internal combustion engine via the E-ECU 23. 1 is performed.

More specifically, the H-ECU 24 does not start the internal combustion engine 1 when the vehicle is stopped or when the load on the accelerator pedal is small, such as when the depression amount of the accelerator pedal is small, and supplies the electric power of the battery 6 to the electric motor 2. The inverter 5 is controlled to apply the voltage. At this time, the electric motor 2 rotates the rotating shaft 2 a with the electric power from the battery 6, and the rotating force of the rotating shaft 2 a is transmitted to the wheels 10,
11, the vehicle travels using only the power of the battery 6 as a drive source.

At this time, the H-ECU 24 constantly monitors the output signal value of the SOC meter 16, and when the output signal value falls below a predetermined value, starts the internal combustion engine 1 via the E-ECU 23, By controlling the generator 3 and the inverter 5, the driving force output from the internal combustion engine 1 is distributed to the generator 3 and the rotating shaft 2 a by the power distribution mechanism 4, and the electric power generated by the generator 3 is And the electric motor 2.

In this case, the rotating shaft 2a of the electric motor 2
Is rotated by the driving force obtained by adding the driving force distributed by the power distribution mechanism 4 and the driving force of the electric motor 2, so that the vehicle has a part of the driving force output from the internal combustion engine 1 and The vehicle travels with a part of the electric power generated by the remaining driving force.

Thereafter, when the output signal of the SOC meter 16 reaches a predetermined charge level, the H-ECU 24 controls the E-ECU 23 to stop the internal combustion engine 1 and controls the electric motor 2 with the electric power of the battery 6. The inverter 5 is controlled to be driven.

Next, when the vehicle is in a normal running state,
The H-ECU 24 uses the driving force of the internal combustion engine 1 (the rotation shaft 2a in the power distribution mechanism 4) without using the electric power of the battery 6.
And the power generated by the driving force distributed to the generator 3 in the power distribution mechanism 4. The vehicle is run only with the internal combustion engine driving force).

At this time, the H-ECU 24 calculates a driving force required by the driver (hereinafter, referred to as a required driving force) based on the depression amount of the accelerator pedal and the like, and then implements the required driving force. A necessary internal combustion engine driving force (hereinafter, required engine driving force) is calculated. And H-ECU
24 transmits the calculated engine required driving force to the E-ECU 23.

Here, the H-ECU 24 to the E-ECU 2
The engine required driving force transmitted to the engine 3 is a value having the intake air amount of the internal combustion engine 1 and the engine speed as parameters, and HE
The CU 24 has a map indicating the relationship between the amount of intake air, the engine speed, and the driving force of the internal combustion engine. The map identifies the amount of intake air and the engine speed corresponding to the desired driving force of the internal combustion engine from this map. The obtained intake air amount and the engine speed are transmitted to the E-ECU 23 as the required engine driving force.

The E-ECU 23 is connected to the H-ECU 2
According to the intake air amount and engine speed specified from 4,
The actuator 19, the spark plug 25, the fuel injection valve 26, and the like are controlled so that the actual driving force of the internal combustion engine matches the required driving force of the engine.

When the amount of depression of the accelerator pedal suddenly increases, such as when the vehicle is accelerating, the H-ECU 2
4 calculates the required driving force from the depression amount of the accelerator pedal, and also calculates the operating state of the internal combustion engine 1, the rotation speed of the electric motor 2, and the stored amount of the battery 6 (the SOC meter 16).
From the output signal value), the total driving force that can be generated in the entire hybrid mechanism is calculated.

Subsequently, the H-ECU 24 compares the required driving force with the total driving force, and if the required driving force is equal to or less than the total driving force, the electric power to be applied from the battery 6 to the electric motor 2. Calculate the amount. Then, the H-ECU 24
Controls the inverter 5 to apply the calculated amount of power from the battery 6 to the electric motor 2. In this case, the vehicle
The vehicle travels with a driving force obtained by adding a driving force (hereinafter, referred to as a battery driving force) output from the electric motor 2 driven by the electric power of the battery 6 and an internal combustion engine driving force.

When the required driving force is larger than the total driving force, the H-ECU 24 controls the E-ECU 23 to increase the driving force of the internal combustion engine and controls the maximum power that can be output from the battery 6 by the electric motor. The inverter 5 is controlled so as to be applied to the motor 2 to increase the total driving force.

Next, the E-ECU 23 operates when the ignition switch (not shown) is in the ON state (the internal combustion engine 1).
Is in operation stop state), the output signal value A of the air-fuel ratio sensor temperature sensor 28 and the output signal value B of the catalyst temperature sensor 15 are input at predetermined time intervals, and the output signal value A is the first signal value. It is determined whether the temperature has dropped below the predetermined temperature T1 and whether the output signal value B has dropped below the second predetermined temperature T2.

The first predetermined temperature T 1 is a temperature higher than the activation temperature of the air-fuel ratio sensor 27 by a predetermined amount, and
The predetermined temperature T2 is a temperature that is higher than the activation temperature of the exhaust purification catalyst 14 by a predetermined amount.

When the E-ECU 23 determines that the output signal value A is lower than the first predetermined temperature T1 and / or that the output signal value B is lower than the second predetermined temperature T2, In order to maintain the temperature of the exhaust purification catalyst 14 and / or the air-fuel ratio sensor 27 at or above the activation temperature, an activation control execution permission request is transmitted to the H-ECU 24.

The H-ECU 24, which has received the activation control execution permission request from the E-ECU 23, determines whether the internal combustion engine 1 is in an operation stop state or an operation state. When the H-ECU 24 determines that the internal combustion engine 1 is in the operation stop state, the H-ECU 24 inputs the output signal value of the SOC meter 16 and determines whether or not the output signal value of the SOC meter 16 is equal to or more than a predetermined value. , Air-fuel ratio sensor heater 3
It is determined whether or not 1 and / or electric power capable of supplying a drive current to the catalyst heater 30 is stored in the battery 6.

If the H-ECU 24 determines that the output signal value of the SOC meter 16 is equal to or greater than a predetermined value, the H-ECU 24 instructs the E-ECU 23 to use the heater 31 for the air-fuel ratio sensor and / or the heater 30 for the catalyst. 14 or execution of the heating control of the air-fuel ratio sensor 27 is permitted. At this time, the E-ECU 23 applies the output current of the battery 6 to the heater 31 for the air-fuel ratio sensor and / or the heater 30 for the catalyst, and raises the temperature of the exhaust purification catalyst 14 to a first predetermined temperature T1 or more and / or The temperature of the fuel ratio sensor 27 is raised to a second predetermined temperature T2 or higher.

If it is determined that the output signal value of the SOC meter 16 is less than a predetermined value, the H-ECU 24
Permits the E-ECU 23 to execute the activation control by starting the internal combustion engine 1. In this case, the E-ECU 23
Starts the internal combustion engine 1 and raises the temperature of the exhaust purification catalyst 14 to a first predetermined temperature T by the heat of the exhaust gas from the internal combustion engine 1.
The temperature of the air-fuel ratio sensor 27 is raised to a second predetermined temperature T2 or higher.

On the other hand, if the H-ECU 24 determines that the internal combustion engine 1 is operating, it inputs the output signal value of the SOC meter 16 and determines whether the battery 6 is in a chargeable state. .

When it is determined that the battery 6 is in a chargeable state, the H-ECU 24 permits the E-ECU 23 to execute the activation control by increasing the output of the internal combustion engine 1. At this time, the H-ECU 24 is
In response to the request, an engine required driving force having the intake air amount of the internal combustion engine 1, the engine speed, and the like as parameters is transmitted.

At this time, the E-ECU 23 is
In order to realize the required engine driving force from the engine 24, the actuator 19, the spark plug 25, the fuel injection valve 26, and the like are controlled to increase the output of the internal combustion engine 1. As a result, the temperature of the exhaust gas from the internal combustion engine 1 increases and the amount of the exhaust gas increases, and the temperature of the exhaust purification catalyst 14 becomes equal to or higher than the first predetermined temperature T.
The temperature of the air-fuel ratio sensor 27 rises to the second temperature T2 or more.

If it is determined that the battery 6 is in a state where charging is impossible, that is, if it is determined that the battery 6 is charged with sufficient power, the H-ECU
24 permits the E-ECU 23 to execute the activation control by the heater 31 for the air-fuel ratio sensor and / or the heater 30 for the catalyst. At this time, the E-ECU 23 applies the output current of the battery 6 to the air-fuel ratio sensor heater 31 and / or the catalyst heater 30, and
4 is raised to a first predetermined temperature T1 or higher and / or the temperature of the air-fuel ratio sensor 27 is raised to a second predetermined temperature T2 or higher.

That is, the E-ECU 23 and the H-ECU 2
4, regardless of whether the internal combustion engine 1 is in the operating state or the operation stopping state, when the charge amount of the battery 6 has a margin, the exhaust gas purification is performed by the air-fuel ratio sensor heater 31 and / or the catalyst heater 30. Keep the parts above the functional activation temperature. On the other hand, the E-ECU 23 and the H-ECU 2
4 indicates that the charge amount of the battery 6 is insufficient and the internal combustion engine 1
Is in an operation stop state, the internal combustion engine 1 is forcibly started, the exhaust gas purifying component is maintained at the function activation temperature or more by the heat of the exhaust gas from the internal combustion engine 1, the charge amount of the battery 6 is not sufficient, and When the internal combustion engine 1 is in the operating state, the internal combustion engine 1 is controlled by increasing the engine speed or the engine load, performing idle-up control, or retarding the ignition timing.
The temperature of the exhaust gas from the exhaust gas is increased, and the exhaust gas purification component is maintained at a temperature above the functional activation temperature.

As described above, the E-ECU 23 and the HE
The CU 24 controls the internal combustion engine 1, the heater 30 for the catalyst, or the heater 31 for the air-fuel ratio sensor based on the output signals of the catalyst temperature sensor 15 and the air-fuel ratio sensor temperature sensor 28. Is achieved.

The operation and effect of this embodiment will be described below. The E-ECU 23 executes an activation control routine as shown in FIG. 2 every predetermined time.

In the activation control routine, EE
First, in S201, the CU 23 inputs the output signal A of the air-fuel ratio sensor temperature sensor 28. Then, E-EC
U23 inputs the output signal B of the catalyst temperature sensor 15 in S202.

Then, the E-ECU 23 proceeds to S203, where the output signal value A is higher than the first predetermined temperature T1, and
Further, it is determined whether or not the output signal value B is higher than a second predetermined temperature T2.

If it is determined in S203 that the output signal value A is higher than the first predetermined temperature T1 and the output signal value B is higher than the second predetermined temperature T2, EE
The CU 23 ends the execution of this routine.

On the other hand, if it is determined in S203 that the output signal value A is equal to or lower than the first predetermined temperature T1 and / or that the output signal value B is equal to or lower than the second predetermined temperature T2, the E-ECU 23 Proceeding to S204, an activation control execution permission request signal is transmitted to the H-ECU 24.

The H-ECU 24 that has received the activation control execution permission request signal from the E-ECU 23 executes an activation control determination routine as shown in FIG. In this activation control determination routine, the H-ECU 24 first
At 301, an activation control execution permission request signal from the E-ECU 23 is received, and then at S302, it is determined whether or not the internal combustion engine 1 is in an operation stop state.

If it is determined in step S302 that the internal combustion engine 1 is in the operation stop state, the H-ECU 24 proceeds to step S302.
Proceeding to 303, the output signal value (battery charge amount) of the SOC meter 16 is input. Then, the H-ECU 24 calculates S
Proceeding to 304, it is determined whether or not the output signal value of the SOC meter 16 is larger than a predetermined value, that is, whether or not the battery 6 is sufficiently charged.

If it is determined in step S304 that the output signal value of the SOC meter 16 is larger than the predetermined value, H-
The ECU 24 proceeds to S305 and transmits to the E-ECU 23 a signal permitting the energization control of the catalyst heater 30 and / or the air-fuel ratio sensor heater 31.

In this case, the E-ECU 23 receives an energization control execution permission signal for the catalyst heater 30 and / or the air-fuel ratio sensor heater 31 in S205 of the activation control routine of FIG. And the E-ECU 23
Applies the output current of the battery 6 to the catalyst heater 30 and / or the air-fuel ratio sensor heater 31 in S206.

The catalyst heater 30 and / or the air-fuel ratio sensor heater 31 to which the output current from the battery 6 is applied
Heats the exhaust purification catalyst 14 and / or the air-fuel ratio sensor 27, sets the exhaust purification catalyst 14 to a temperature higher than the first predetermined temperature T1, and sets the air-fuel ratio sensor 27 to the second predetermined temperature T2.
Raise the temperature to a higher temperature.

On the other hand, if the H-ECU 24 determines in S304 that the output signal value of the SOC meter 16 is equal to or less than the predetermined value, the H-ECU 24 proceeds to S306 and outputs a signal for permitting the start control of the internal combustion engine 1 to the E-ECU 23. Send to

In this case, the E-ECU 23 receives the start control execution permission signal of the internal combustion engine 1 in S205 of the activation control routine of FIG. And EE
In step S206, the CU 23 starts the internal combustion engine 1, sets the exhaust purification catalyst 14 to a temperature higher than the first predetermined temperature T1 by the heat of the exhaust gas discharged from the internal combustion engine 1, and sets the air-fuel ratio sensor 27 to the second predetermined temperature. Raise the temperature to a temperature higher than T2.

When the start control of the internal combustion engine 1 is performed as described above, the driving current output from the internal combustion engine 1 is mainly used for charging the battery 6 and the output current of the battery 6 is used for the catalyst heater 30. And / or heating to the air-fuel ratio sensor heater 31, heating by the exhaust heat and the heater 30,
The heating by 31 may be performed in parallel.

Next, when it is determined in S302 that the internal combustion engine 1 is in the operating state, the H-ECU 24
Proceeding to S307, the output signal value (battery charge) of the SOC meter 16 is input. Then, the H-ECU 24
Proceeding to S308, it is determined whether or not the battery 6 can be charged based on the battery charge amount.

If it is determined in step S308 that the battery 6 can be charged, the H-ECU 24 proceeds to step S30.
9, a signal for permitting the engine output increase control (for example, the engine speed increase control, the engine load increase control, the idle-up control, or the ignition timing retard control, etc.) is issued.
Send to CU23. At that time, the H-ECU 24 transmits information specifying the driving force output from the internal combustion engine 1 (engine required driving force) together with the engine output increase control permission signal.

In this case, the E-ECU 23 receives the engine output increase control execution permission signal of the internal combustion engine 1 and the engine required driving force information in S205 of the activation control routine of FIG. Then, the E-ECU 23 determines in S206
In step (1), the actuator 19a, the fuel injection valve 26, the spark plug 25, and the like are controlled to increase the driving force output from the internal combustion engine 1 so that the actual driving force of the internal combustion engine matches the required driving force of the engine.

As a result, the temperature of the exhaust gas discharged from the internal combustion engine 1 increases, and at the same time, the amount of the exhaust gas increases.
At the same time as the temperature of the exhaust purification catalyst 14 rises to a temperature higher than the first predetermined temperature T1, the temperature of the air-fuel ratio sensor 27 rises to a temperature higher than the second predetermined temperature T2.

When the engine output increase control is executed as described above, the battery 6 is charged by using a part of the driving force of the internal combustion engine 1 and the output current of the battery 6 is controlled by the catalyst heater 30 or the like. The heating by the exhaust heat and the heating by the heaters 30 and 31 may be applied in parallel to the heater 31 for the air-fuel ratio sensor.

On the other hand, when it is determined in S308 that the battery 6 cannot be charged, that is, when it is determined that the battery 6 is sufficiently charged, the H-ECU 2
4 proceeds to S305, and transmits a signal to the E-ECU 23 for permitting energization control of the catalyst heater 30 and / or the air-fuel ratio sensor heater 31.

Then, the E-ECU 23 applies the output current of the battery 6 to the catalyst heater 30 and / or the air-fuel ratio sensor heater 31 in S206 of the activation control routine of FIG.

In this case, the exhaust gas purifying catalyst 14 and / or the air-fuel ratio sensor 27 are heated by the exhaust gas from the internal combustion engine 1 and the catalyst heater 30 and / or the air-fuel ratio sensor heater 31, so that the first Then, the temperature is raised to a higher temperature by the second predetermined temperatures T1 and T2.

As described above, according to the internal combustion engine control apparatus of this embodiment, the temperatures of the exhaust purification catalyst 14 and the air-fuel ratio sensor 27 are monitored at predetermined time intervals, and the exhaust purification catalyst 14 and the air-fuel ratio sensor are monitored. 27, the exhaust purification catalyst 14 and / or the air-fuel ratio sensor 27 are heated when the temperature falls below the temperatures T1 and T2 set in the temperature range higher than the respective activation temperatures. The air-fuel ratio sensor 27 is always kept at the activation temperature or higher.

As a result, even immediately after the start of the internal combustion engine 1, the air-fuel ratio sensor 27 and the exhaust purification catalyst 14 are in an activated state, and accurate air-fuel ratio feedback control based on the output signal value of the air-fuel ratio sensor 27 is performed. As a result, the air-fuel ratio of the exhaust gas flowing into the exhaust purification catalyst 14 becomes the desired air-fuel ratio, and the exhaust emission does not deteriorate.

In the present embodiment, a hybrid mechanism in which an internal combustion engine and an electric motor are combined via a power split mechanism has been described as an example of a hybrid mechanism to which the present invention is applied. However, the present invention is not limited to this. Instead, for example, a series-type hybrid mechanism in which an internal combustion engine and an electric motor are arranged in series, or a parallel-type hybrid mechanism in which an internal combustion engine and an electric motor are arranged in parallel may be used. Any hybrid mechanism in which start and stop are repeated or a hybrid mechanism in which the internal combustion engine is continuously operated with a constant load may be used.

[0089]

In the control apparatus for an internal combustion engine of a hybrid vehicle according to the present invention, the exhaust purification parts of the internal combustion engine are always maintained at a temperature higher than the function activation temperature. Can purify the exhaust,
Exhaust emissions do not deteriorate.

In the case where the internal combustion engine control device of the hybrid vehicle includes the temperature detecting means and the temperature increasing means, when the temperature detected by the temperature detecting means tends to decrease,
That is, when the temperature of the exhaust purification component tends to be lower than the function activation temperature, the temperature of the exhaust purification component is increased by the temperature increasing means before the temperature of the exhaust purification component becomes lower than the function activation temperature, Exhaust emission deterioration can be suppressed.

Further, when the internal combustion engine control device of the hybrid vehicle includes the charged amount detecting means, the temperature detecting means, and the heating means, the operation state of the internal combustion engine is changed when the charged amount of the charged power means has a margin. Therefore, the temperature of the exhaust purification component can be increased without causing the exhaust gas emission component to deteriorate while suppressing the fuel consumption rate of the internal combustion engine.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a hybrid mechanism of a hybrid vehicle to which an internal combustion engine control device according to the present invention is applied.

FIG. 2 is a flowchart showing an activation control routine.

FIG. 3 is a flowchart illustrating an activation control determination routine;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Internal combustion engine 2 ... Electric motor 3 ... Generator 4 ... Power distribution mechanism 5 ... Inverter 6 ... Battery 7 ... Reduction gear 14. Exhaust purification catalyst 15 ... Catalyst temperature sensor 16 SOC meter 23 E-ECU 24 H-ECU 27 Air-fuel ratio sensor 28 Air-fuel ratio sensor temperature sensor 30 Heater for catalyst 31 Heater for air-fuel ratio sensor

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI G05D 23/00 G05D 23/00 D

Claims (5)

[Claims] An internal combustion engine, a generator driven by the internal combustion engine, a power storage means for storing power generated by the generator, and a motor driven by the power of the generator or the power storage means; An engine control unit for a hybrid vehicle, comprising: an engine control unit that controls the internal combustion engine according to at least one of a vehicle operating state and a state of the power storage unit, and purifies exhaust gas from the internal combustion engine. An internal combustion engine control device for a hybrid vehicle, comprising: a temperature maintaining unit that maintains a temperature of an exhaust purification component at a temperature equal to or higher than a functional activation temperature. 2. The temperature holding means comprises: a temperature detecting means for detecting a temperature of the exhaust gas purifying component; and a temperature for activating the exhaust gas purifying component when the temperature detected by the temperature detecting means tends to decrease. 2. The internal combustion engine control apparatus for a hybrid vehicle according to claim 1, further comprising a temperature increasing unit configured to increase a temperature of the exhaust gas purification component so as to maintain the temperature. 3. The internal combustion engine control apparatus for a hybrid vehicle according to claim 2, wherein said temperature increasing means forcibly starts said internal combustion engine via said engine control means. 4. An internal combustion engine control apparatus for a hybrid vehicle according to claim 2, wherein said temperature increasing means is heating means for heating said exhaust gas purifying component. 5. The temperature holding unit includes: a storage amount detection unit configured to detect a storage amount of the storage unit; a temperature detection unit configured to detect a temperature of the exhaust gas purification component; Heating means for heating the exhaust gas purifying component, wherein the temperature detected by the temperature detecting means tends to decrease, and if the charged amount detected by the charged amount detecting means is equal to or more than a predetermined value, the heating means By heating the exhaust gas purifying component according to the above, if the temperature detected by the temperature detecting means is in a tendency to decrease, and if the amount of stored power detected by the charged amount detecting means is less than a predetermined value, through the engine control means The internal combustion engine control apparatus for a hybrid vehicle according to claim 1, wherein an operation state of the internal combustion engine is changed.