JP2001207894A - Direct injection engine control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form an excellent air-fuel mixture in a direct injection engine with a turbocharger. SOLUTION: Pressure (intake pressure) of air to be sucked in a cylinder 111 is detected by an intake pressure detecting sensor 64 arranged in an intake air passage 21 just upstream of a combustion chamber 100. When a computer 5 judges that an engine is in an acceleration state from a change in opening of an accelerator 61, the injection timing is corrected to the ignition timing delay side as the intake pressure becomes low, that is, as the intake pressure becomes lower than intake pressure at steady operation time due to a turbo lag to offset a strengthening quantity of fuel atomization penetration by pressure reduction in the intake pressure to optimize the arrival timing of fuel atomization to a spark plug 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to control of a direct injection engine with a turbocharger, and more particularly to improvement of combustion performance.

[0002]

2. Description of the Related Art Today, even in the field of gasoline engines for motive power of vehicles and the like, an injector provided through a combustion chamber wall like a diesel engine directly enters a combustion chamber.
Direct injection engines that inject fuel have been put to practical use. In a direct injection engine, for example, by injecting fuel from an injector toward a cavity provided at the top of a piston during a compression stroke, an air-fuel mixture having an air-fuel ratio close to a stoichiometric air-fuel ratio is generated around an ignition plug at the ignition timing. I have. This makes it possible to reliably ignite even if the air-fuel ratio is lean overall,
And the amount of HC emission can be reduced, and the fuel efficiency during idling operation and low load traveling can be greatly improved. In addition, even when the fuel injection amount is increased or decreased, there is no fuel transfer delay due to the transport time in the intake passage as in a normal engine, so that the acceleration / deceleration response of the engine speed can be improved.

[0003] As described above, the direct injection engine has a structure suitable for so-called lean combustion. However, in order to further improve the combustion performance, a turbocharger is mounted to increase the in-cylinder intake air amount, thereby improving fuel efficiency. There is one in which the lean combustion region leading to a high load region is expanded to a higher load region.

On the other hand, in a direct injection engine control device attached to a direct injection engine, various attempts have been made to control various parts of the direct injection engine, such as fuel injection and intake control.

[0005] For example, in a direct injection engine, fuel is directly injected into the combustion chamber. Therefore, during high load operation in which the required fuel injection increases, the air-fuel ratio in the vicinity of the ignition plug may become over-rich and misfire may occur. In order to solve such a problem, for example, Japanese Patent Application Laid-Open Nos.
Japanese Patent Application Publication No. -1029776 proposes switching between a compression stroke injection mode in which fuel is injected in a compression stroke (late injection mode) and an intake stroke injection mode in which fuel is injected in an intake stroke (previous injection mode) in accordance with load. Have been.

Specifically, during low load operation with a small amount of fuel injection, fuel is injected into the cavity formed by the deep plate and the concave groove during the compression stroke, so that the air-fuel ratio around the ignition plug is close to the stoichiometric air-fuel ratio. A mixture is formed locally (late injection mode), and during high-load driving with a large amount of fuel injection, fuel is injected outside the cavity during the intake stroke to form a mixture with a uniform air-fuel ratio over the entire area of the combustion chamber. A large amount of fuel is burned in the same manner as the intake pipe injection type engine (first injection mode). In addition, during the middle load traveling, a certain amount of the entire required fuel injection amount is injected in the first injection mode, and the shortage of ignition in the first injection mode is injected in the second injection mode.

Further, the valve opening timing of the injector, that is, the injection timing, is within a range in which fuel injection is completed during the intake stroke or the compression stroke based on the injector opening time set based on the required fuel injection amount and the fuel pressure. In particular, in the compression stroke injection mode, there is a possibility that the fuel in the cavity at the time of ignition does not vaporize reliably, resulting in incomplete combustion depending on the timing. In order to solve such a problem, the injection timing is determined in consideration of the time required for vaporizing the fuel and the time required for diffusing the spray. For example, Japanese Patent Application Laid-Open No. H11-141115 discloses that the vaporization rate of fuel and the diffusion rate of spray change under the influence of the ambient temperature, specifically, the in-cylinder temperature. Focusing on the fact that it is not much affected, it has been proposed to calculate the injection timing according to the engine temperature and optimize the fuel vaporization state and the spray diffusion state at the time of ignition.

Specifically, at a high temperature where the vaporization rate greatly changes with the injection timing, the fuel injection timing is set within a range where the fuel vaporization rate is secured to some extent and the stratification does not decrease so much. At low temperatures that do not depend on
By retarding the fuel injection timing, the fuel stratification is increased by that amount to achieve stable combustion.

[0009]

By the way, in addition to the above-described fuel vaporization properties due to the in-cylinder ambient temperature and the degree of spray diffusion according to the interval time from fuel injection to ignition,
The penetration pressure of the spray varies depending on the atmospheric pressure in the cylinder, and the degree of diffusion of the spray varies depending on the gas flow velocity in the cylinder, thereby affecting the mixture formation. For example, when the supercharging pressure is increased, the in-cylinder intake air amount is increased, so that the in-cylinder pressure at a predetermined crank angle in the compression stroke is increased. There is a possibility that the arrival time is delayed, and thus an optimal mixture field is not formed around the spark plug at the ignition timing. In addition, when the supercharging pressure increases, the flow velocity of the gas flowing into the cylinder increases, so that the diffusion of the spray is promoted, the stratification of the air-fuel mixture in the cylinder decreases, and the combustion fluctuation deteriorates. Eventually, it may be difficult to achieve lean combustion itself.

[0010] In a direct injection engine equipped with a turbocharger, the pressure of the air taken into the cylinder (hereinafter referred to as the in-cylinder suction pressure or simply the intake pressure) that defines the above-mentioned in-cylinder atmospheric pressure varies widely. In particular, when a supercharging delay generally called a turbo lag occurs, the air-fuel mixture field in the combustion chamber may greatly deviate from the optimal one, and the combustion state may be deteriorated.

The present invention has been made in view of the above circumstances,
It is an object of the present invention to provide a direct-injection engine control device that can form an appropriate air-fuel mixture even with a turbo lag or the like.

[0012]

According to the first aspect of the present invention, there is provided a direct injection engine control device which is attached to a direct injection engine which has a turbocharger and directly injects fuel from an injector into a combustion chamber. Is provided. An intake pressure sensor provided in the intake passage at a position immediately upstream of the combustion chamber and detecting an in-cylinder intake pressure; an acceleration detecting means for detecting an acceleration of the direct injection engine; and a fuel injection when the acceleration exceeds a predetermined value. An injection timing correction means for correcting the injection timing based on the in-cylinder intake pressure is provided.

When the vehicle is in an acceleration state exceeding a certain level, a turbo lag is generated. As a result, the in-cylinder state such as the in-cylinder pressure changes in comparison with an operation range in which acceleration is considered to be substantially negligible.
By the correction of the injection timing, the state of the injected fuel and the changed in-cylinder state match to form an appropriate mixed gas field in the combustion chamber.

In addition, since the intake pressure is directly detected,
Individual differences and aging of the turbocharger can be absorbed.

According to a second aspect of the present invention, in the configuration of the first aspect, the injection timing correction means sets the injection timing to be retarded as the in-cylinder intake pressure decreases.

[0016] Due to the turbo lag, the in-cylinder intake pressure becomes relatively low as compared with an operation range in which acceleration is considered to be substantially negligible, and the penetration of fuel spray becomes excessive. This shortens the time from fuel injection to the mixture reaching the spark plug. This reduced time is offset by the retarded injection timing, and an appropriate mixture field is formed in the combustion chamber.

According to a third aspect of the present invention, a direct injection engine control device attached to a direct injection engine having a turbocharger and directly injecting fuel from a injector into a combustion chamber has the following configuration. An intake pressure sensor provided in the intake passage at a position immediately upstream of the combustion chamber and detecting an in-cylinder intake pressure; an acceleration detecting means for detecting an acceleration of the direct injection engine; and a fuel injection when the acceleration exceeds a predetermined value. Fuel pressure correcting means for correcting the fuel pressure based on the in-cylinder intake pressure.

When the vehicle is in an acceleration state exceeding a certain level, a turbo lag is generated. As a result, the in-cylinder state such as the in-cylinder pressure changes in comparison with an operation range in which acceleration is considered to be substantially negligible.
By the correction of the fuel pressure, the state of the injected fuel and the changed in-cylinder state match to form an appropriate mixed gas field in the combustion chamber.

Moreover, since the intake pressure is directly detected,
Individual differences and aging of the turbocharger can be absorbed.

According to a fourth aspect of the present invention, in the configuration of the third aspect, the fuel pressure correcting means sets the fuel pressure to be lower as the in-cylinder intake pressure is lower.

Due to the turbo lag, the in-cylinder intake pressure is relatively reduced as compared with an operation range in which acceleration is considered to be substantially negligible, and this acts in a direction to enhance the penetration of fuel spray. This strengthening action of the fuel spray penetration is offset by the weakening action of the fuel spray penetration due to the lowering of the fuel pressure, and an appropriate mixture field is formed in the combustion chamber.

According to a fifth aspect of the present invention, in the configuration of the first to fourth aspects of the invention, the intake pressure sensor is provided in a surge tank to detect a pressure in the surge tank as the in-cylinder intake pressure.

A detection value accurately reflecting the in-cylinder intake pressure without pressure pulsation can be obtained.

According to a sixth aspect of the present invention, in the configuration of the first to fifth aspects, the acceleration detecting means detects an accelerator opening as the acceleration.

It is not necessary to directly detect the rotation state of the crankshaft and the like, and the configuration can be simplified.

According to a seventh aspect of the present invention, in the configuration of the first to sixth aspects, when the acceleration exceeds a predetermined value, the throttle opening is corrected to the open side as the in-cylinder intake pressure is lower. A throttle opening correction means is provided.

The shortage of the in-cylinder intake air amount due to the turbo lag can be suppressed.

According to an eighth aspect of the present invention, a direct injection engine control device attached to a direct injection engine having a turbocharger and directly injecting fuel from an injector into a combustion chamber has the following configuration. An acceleration detection means for detecting the acceleration of the direct injection engine, and an expansion stroke injection command means for instructing the injector to perform additional fuel injection during the expansion stroke when the acceleration exceeds a predetermined value.

In the expansion stroke, additional combustion is performed by the added injected fuel, thereby increasing the exhaust energy, shortening the turbo lag time and improving the rise of the turbocharger. Thus, a change in the penetration of the fuel spray is suppressed, and an appropriate mixture field can be formed in the combustion chamber.

Further, the combustion of the fuel by the compression stroke injection is particularly susceptible to the influence of the in-cylinder atmosphere, and the invention of claims 1 to 8 is the compression stroke of performing the fuel injection during the compression stroke as in the invention of claim 9 It is particularly preferable to apply the present invention to a direct injection engine control device in which an injection mode can be set.

[0031]

(First Embodiment) FIG. 1 shows a direct injection engine provided with a direct injection engine control device of the present invention.
The direct injection engine will be described below as a vehicle engine. In the direct injection engine, a piston 13 is slidably held in a cylinder 111 formed in a cylinder block 11, and a combustion chamber 100 is formed above the piston 13 inside a cylinder head 12. . The mixture of fuel and air is burned in the combustion chamber 100, and the explosive force causes the piston 13 to reciprocate up and down, thereby rotating the crankshaft. A recess (not shown) is formed on the top surface of the piston 13 to form a cavity. The ignition of the air-fuel mixture is performed by a spark plug 4 provided through the cylinder head 12 and protruding into the combustion chamber 100.
It is performed by

The air constituting the air-fuel mixture is supplied through the intake passage 21. Further, exhaust from the combustion chamber 100 is performed through an exhaust passage 22. The cylinder head 12 has an intake valve 201 for switching between communication and shutoff between the intake passage 21 and the combustion chamber 100, and an exhaust valve 2 for switching between communication and shutoff between the exhaust passage 22 and the combustion chamber 100.
02 is attached.

A flap-shaped throttle valve 205 is provided in the intake passage 21, and the amount of air in the intake passage 21 is adjusted according to the degree of opening.

The engine has a turbocharger 204.
Is provided to increase the intake pressure to a supercharging pressure according to the exhaust energy.

The fuel constituting the air-fuel mixture is supplied by an injector 31 provided through the cylinder head 12, and the fuel is directly injected into the combustion chamber 100 from the nozzle at the tip end.

The fuel is supplied to the injector 31 by the fuel from the fuel tank 34 being pressurized by the fuel pump 33 and supplied to the injector 31 via the delivery pipe 32. The pressure in the delivery valve 32, that is, the fuel pressure is adjustable by controlling the discharge amount of the fuel pump 33.

The direct injection engine control device comprises an engine control computer 5 which is injection timing correction means, fuel pressure correction means and throttle opening correction means, and sensors 61, 62, 63, 64 and the like input to the computer. And controls such as fuel injection control, intake control, and ignition control. The engine control computer 5 includes a CPU, a RAM,
It has a general configuration including a ROM and the like. The injector 31, the throttle valve 20 and the throttle valve 20 are configured based on operation states known from detection signals from the sensors 61 to 64 and the like.
5. Output a control signal to the ignition plug 4, the fuel pump 33, and the like.

The sensors 61 to 64 will be described. From an accelerator pedal 61 which is an acceleration detecting means,
When the driver steps on this, the amount of depression (accelerator opening) is known. A crank angle signal is input from the crank angle sensor 62, and the crank angle is known. From the cooling water temperature sensor 63, the temperature of the cooling water of the engine is known.

The intake pressure sensor 64 is provided in the surge tank 203 in the intake passage 21 and detects the pressure in the surge tank 203 as the intake pressure. By providing the intake pressure sensor 64 in the surge tank 203 having no pressure pulsation in this way, it is possible to accurately detect the in-cylinder intake pressure. In addition, a general sensor signal known for controlling an engine is input to the engine control computer 5.

FIG. 2 shows the contents of control in the engine control computer 5, which shows the procedure for setting the fuel injection timing and the like, and mainly describes the fuel injection control and the intake control. First, the processing is started when the power is turned on, and all memories,
The registers and ports are initialized. Subsequent processing is a time synchronization routine repeatedly executed at predetermined time intervals.

First, in step S101, the sensors 6
Engine speed N based on output signals from
E, accelerator opening VA, intake pressure PM, cooling water temperature THW
Etc.

In step S102, the operating state is determined from the engine speed NE and the like, and the optimum combustion method is determined according to the operating state. As a method of determining the combustion method, as shown in FIG. 3, the fuel is injected in the stratified combustion or the intake stroke by the fuel injected in the compression stroke in accordance with the two-dimensional map in which the engine speed NE and the accelerator opening VA are input. Select either homogeneous combustion with fuel. Hereinafter, a description will be given assuming that stratified combustion, which is a characteristic part of the present invention, is selected.

Subsequently, a fuel injection amount QF, a basic injection timing TB, a basic injection pressure PB, and a basic throttle opening ThB are calculated based on the above-mentioned operation state. Here, the basic injection timing TB
The basic injection pressure PB and the basic throttle opening ThB are shown in FIG.
As shown in the figure, the engine speed NE and the fuel injection amount Q
Set by a two-dimensional map with F as input.

In step S103, the accelerator opening VA
It is determined whether or not the current operation state is the acceleration state based on the amount of time change of. That is, VAi is the current calculated value of the accelerator opening, and VAi-1 is the previous calculated value (VAi-VAi-1).
) Is equal to or greater than a predetermined value K, it is determined that the vehicle is accelerating, and the process proceeds to step S104. The greater the acceleration, the greater the influence of the turbo lag on the mixture formation. Therefore, the higher the required quality of the combustion state, the smaller the predetermined value K is set.

In step S104, the engine speed N
The in-cylinder intake air amount Qair is calculated based on E and the intake pressure PM. The calculation is performed by interpolation from a data map created from the in-cylinder intake air amount measured under the steady operation of the engine.

The following step S105 is a procedure showing the operation as the fuel injection timing correction means and the fuel pressure correction means. The in-cylinder intake air amount Qair calculated in the above step S104,
An injection timing Tair and an injection pressure Pair are calculated based on the in-cylinder intake air amount from the engine speed NE and the fuel injection amount QF. The injection timing Tair and the injection pressure Pair will be described with reference to the data map of FIG. 4. When the engine is in a steady state, the basic injection timing TB and the basic injection pressure PB calculated on the basis of the accelerator opening calculated in step S102. Matches. On the other hand, during acceleration, as the in-cylinder intake air amount Qair becomes smaller, the equal fuel injection amount QF line of the injection timing is given so as to move to the retard side as a whole. Also, the smaller the in-cylinder intake air amount Qair, the more the fuel injection equal fuel injection amount QF line of the fuel pressure is shifted to the lower pressure side as a whole.

The following step S106 is a procedure showing the operation as the throttle opening correction means. The intake pressure PM detected in step S102 and the current engine speed N
E, The supercharging delay amount (PMs-PM) is calculated from the steady-state intake pressure PMs (= f (NE, Thi-1)) calculated from the throttle opening degree Thi-1, and the supercharging delay amount (PMs-PM) is calculated. PMs -P
The correction amount Thc of the throttle opening is calculated according to M).
Here, the correction amount is set to the valve opening side as the supercharging delay amount increases. As a result, the intake air amount is corrected to an appropriate value according to the fuel injection amount QF. Next, step S1
Proceed to 07.

In step S103, (VAi-VA
i-1) If <K, it is determined that the engine is in a steady operation state in which there is substantially no acceleration. In step S108, the injection timing Tair is set to the basic injection timing TB value, the fuel pressure Pair is set to the basic fuel pressure PB, and the throttle opening correction amount Thc is set. The process proceeds to step S107 as 0.

In step S107, the final injection timing TF,
The final fuel pressure PF and the final throttle opening ThF are calculated. The calculation of the final injection timing TF takes a value on the retard side between the basic injection timing TB and the in-cylinder intake amount base injection timing Tair.
If it is determined that the vehicle is accelerating, the final injection timing TF becomes the in-cylinder intake air amount-based injection timing Tair. If it is determined that the vehicle is in the steady state, the final injection timing TF becomes the basic injection timing TB. The final fuel pressure PF is calculated on the lower pressure side of the basic fuel pressure PB and the in-cylinder intake air amount base fuel pressure Pair. If it is determined that the vehicle is accelerating, the final injection timing PF is determined by the in-cylinder intake air amount base fuel pressure Pair. And the final fuel pressure PF becomes the basic fuel pressure PB value when it is determined that the engine is in the steady state.

The final throttle opening ThF is calculated by adding a correction amount Thc to the basic throttle opening ThB. Therefore, the final throttle opening ThF is a value obtained by opening the correction amount Thc more than the basic throttle opening ThB when it is determined that the vehicle is accelerating, and becomes the basic throttle opening ThB when it is determined that the vehicle is in a steady state.

These final injection timing TF, final fuel pressure PF,
This flow ends when the final throttle opening ThF is calculated.

Now, during acceleration, the rise of the supercharging pressure is delayed (turbo lag) from the steady state, so that the in-cylinder intake air amount becomes lower than the steady state value. Since this acts in the direction of enhancing the penetration of the fuel spray, the smaller the in-cylinder intake air amount Qair, that is, the greater the amount of decrease in the in-cylinder intake air amount Qair from the steady state value due to the turbo lag, the greater the above-described effect. Correcting the injection timing and the fuel pressure to the retard side and the low pressure side has the following effects. That is, by correcting the injection timing to the retard side and shortening the interval from the injection to the ignition timing, the arrival timing of the air-fuel mixture to the spark plug 4 due to excessive penetration of the fuel spray is prevented from being too early. Further, by correcting the fuel pressure to the low pressure side, the effect of weakening the fuel spray penetration and the effect of enhancing the fuel spray penetration due to a relative decrease from the steady state value of the in-cylinder intake pressure are offset. In addition, the in-cylinder intake amount-based injection timing Tair,
Since the in-cylinder intake air amount Qair for calculating the in-cylinder intake amount-based fuel pressure Pair is calculated based on the intake pressure PM detected by the intake pressure sensor 64 (step S104), it is affected by turbo lag and the like. And a highly accurate value can be obtained. Thus, even when turbo lag occurs during acceleration, the timing of the mixture reaching the spark plug 4 is optimized, an appropriate mixture field is formed, and deterioration of combustion due to the turbo lag can be prevented.

Further, by correcting the opening of the throttle valve, it is possible to suppress a decrease in the intake air amount in the cylinder due to the turbo lag.

In the above description, the control in the compression stroke injection has been described.
By applying the same correction to the fuel injection and the intake air, the influence of the change in the in-cylinder intake air amount can be reduced. However, as a special effect of the decrease in the amount of in-cylinder intake air during the intake stroke injection that occurs during acceleration, the enhancement of the spray penetration causes the spray to collide with and adhere to the piston cavity or cylinder liner, producing fuel that is not effectively provided for combustion. There is a tendency that when the injection timing is advanced, adhesion to the cavity occurs, and when the injection timing is retarded, adhesion to the liner side occurs. Therefore, for the correction of the injection timing, it is preferable to set the correction direction of the advance angle and the retard angle in accordance with the basic injection timing.

In this embodiment, the injection timing correction and the fuel pressure correction act to optimize the timing at which the air-fuel mixture reaches the ignition plug 4 as described above. A configuration in which only one of them is performed may be adopted.

The installation position of the intake pressure sensor 64 is determined not by the surge tank 203 but by a location where a pressure value reflecting the in-cylinder intake pressure is obtained in accordance with the accuracy of the timing at which the required mixture reaches the spark plug 4. If so, it can be set at any position in the intake passage 21 immediately upstream of the combustion chamber 100.

The fuel pressure is adjusted by setting the discharge amount of the fuel pump 33. For example, a part of the fuel in the delivery pipe 32 is controlled through a pressure regulating valve capable of adjusting the opening. The pressure may be adjusted to a predetermined value in accordance with the opening of the pressure regulating valve by relief to the tank 34.

(Second Embodiment) Next, a direct injection engine control device according to a second embodiment of the present invention will be described. First
In the embodiment, the control software in the engine control computer is replaced with another one, and the hardware configuration will be described with the numbers in FIG.

FIG. 5 shows the fuel injection control and the intake control in the engine control computer 5 according to the present embodiment. After the power is turned on, the processing is started, and the initial control (not shown) is executed in the same manner as in the first embodiment. First, in step S201, an operation state detection signal such as sensors 61 to 64 is read, and then in step S201.
At 202, an acceleration determination is performed in the same manner as in the first embodiment (see step S103).

If it is determined in step S202 that the vehicle is accelerating, stratified charge combustion in the compression stroke injection mode is forcibly determined (step S203).

In step S204, a fuel injection amount Q, an injection timing T, a fuel pressure P, and a basic throttle opening ThB are calculated.
The calculation here is the same as the calculation of the basic fuel injection amount QB, the basic injection timing TB, the basic fuel pressure PB, and the basic throttle opening ThB in step S102 of the first embodiment.

In step S205, a throttle opening correction amount Thc 'is calculated. Here, the throttle opening correction amount Thc 'is given to the injection amount Q and the engine speed NE calculated in step S204, and the throttle opening is set to the open side until the fuel injection amount Q can reach the lean limit at which combustion is possible. Will be corrected. This is to provide a sufficient amount of air for combustion of fuel additionally injected in an expansion stroke described later.

Step S206 is a procedure as expansion stroke injection command means, in which the conditions of the expansion stroke injection, that is, the fuel injection amount Q2 and the injection timing T2 are set. The expansion stroke injection is a fuel injection for injecting fuel in the expansion stroke and generating combustion again using the main combustion flame of the fuel injected by the compression stroke injection as an ignition source.
2 and the injection timing T2 are calculated according to a two-dimensional map having the engine speed NE and the compression stroke injection amount Q as inputs. Here, the fuel injection amount Q2 can avoid generation of smoke from the exhaust gas discharged from the exhaust passage 22 in consideration of the increased in-cylinder intake air amount corresponding to the corrected throttle opening (step S205). It is desirable to set the upper limit. Further, the injection timing T2 is set so that the main combustion, in which the flame of the main combustion can be used as a fire type, is ongoing and the combustion does not contribute to the engine output.

In step S207, a correction amount Thc 'is added to the throttle opening to output the final throttle opening.

If it is determined in step S202 that the vehicle is not accelerating, either stratified charge combustion in the compression stroke injection mode or homogeneous combustion in the intake stroke injection mode is selected according to the operation state (step S208). The control in the non-acceleration state is the same as that in the steady-state combustion of the first embodiment.

With the above control, stratified charge combustion is performed during acceleration, engine output is ensured, the amount of in-cylinder intake air is increased to the limit at which combustion can be performed, and combustion is continued by fuel from the expansion stroke injection to exhaust gas. Increase the temperature. Thus, the rise of the turbo rotation can be improved by increasing the input energy to the turbocharger 204, and the turbo lag time can be shortened.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a main part of a direct injection engine provided with a first direct injection engine control device of the present invention.

FIG. 2 is a flowchart showing control contents in the direct injection engine control device.

FIG. 3 is a first data map showing control contents in the direct injection engine control device.

FIGS. 4A, 4B, and 4C are second, third, and fourth data maps showing control contents in the direct injection engine control device.

FIG. 5 is a flowchart showing control contents in a second direct injection engine control device of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 combustion chamber 21 intake passage 22 exhaust passage 201 intake valve 202 exhaust valve 203 surge tank 204 turbocharger 205 throttle valve 31 injector 5 engine control computer 61 accelerator 62 crank angle sensor 63 cooling water temperature sensor 64 intake pressure sensor

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F02D 23/02 F02D 23/02 H J41 / 02 310 41/02 310D 310F 330 330D 330F 335 335 41/32 41/32 A 41/34 41/34 E H 45/00 364 45/00 364D 364H F term (reference) 3G084 BA05 BA14 BA15 DA05 EA07 EA11 EB09 FA10 FA11 FA33 FA38 FA39 3G092 AA01 AA06 AA09 AA18 BB01 BB06 BB13 DC02 EA01 EA04 EA06 EA07 EA11 FA10 FA36 FA48 GA12 HA01Z HA05Z HA06X HA16Z HB02X HB03X HE03Z HE08Z HF09Z 3G301 HA01 HA11 HA16 JA12 JA15 JA21 KA12 LA03 LB04 LB06 MA03 MA19 MA23 NE06 NE12 NE14 NE15 PA11Z PAZZZZZZZZZZZBZZ

Claims (9)

[Claims] 1. Each part of a direct injection engine having a turbocharger and being attached to a direct injection engine for directly injecting fuel from a injector into a combustion chamber and including fuel injection control and intake control based on an operation state of the direct injection engine. Direct-injection engine control device, the intake pressure sensor provided in the intake passage at a position immediately upstream of the combustion chamber and detects in-cylinder intake pressure, acceleration detection means for detecting the acceleration of the direct injection engine, A direct injection engine control device comprising: injection timing correction means for correcting the injection timing of fuel injection based on the in-cylinder intake pressure when the acceleration exceeds a predetermined value set in advance. 2. The direct injection engine control device according to claim 1, wherein the injection timing correction means sets the injection timing to be retarded as the in-cylinder intake pressure is lower. 3. Each part of a direct injection engine having a turbocharger and being attached to a direct injection engine that directly injects fuel from a injector into a combustion chamber and including fuel injection control and intake control based on an operating state of the direct injection engine. Direct-injection engine control device, the intake pressure sensor provided in the intake passage at a position immediately upstream of the combustion chamber and detects in-cylinder intake pressure, acceleration detection means for detecting the acceleration of the direct injection engine, A direct injection engine control device comprising: fuel pressure correction means for correcting the fuel pressure of fuel injection based on the in-cylinder intake pressure when the acceleration exceeds a predetermined value set in advance. 4. The direct injection engine control device according to claim 3, wherein the fuel pressure correction means sets the fuel pressure to be lower as the in-cylinder intake pressure is lower. 5. The direct injection engine control device according to claim 1, wherein said intake pressure sensor is provided in a surge tank to detect a pressure in the surge tank as said in-cylinder intake pressure. Control device. 6. A direct injection engine control device according to claim 1, wherein said acceleration detection means detects an accelerator opening as said acceleration. 7. The direct injection engine control device according to claim 1, wherein when the acceleration exceeds a predetermined value, the throttle opening is corrected to the opening side as the in-cylinder intake pressure is lower. A direct injection engine control device provided with an opening correction means. 8. Each part of a direct injection engine having a turbocharger and being attached to a direct injection engine for directly injecting fuel from an injector into a combustion chamber and including fuel injection control and intake control based on an operation state of the direct injection engine. A direct injection engine control device for controlling the acceleration of the direct injection engine, and instructing the injector to perform additional fuel injection during an expansion stroke when the acceleration exceeds a predetermined value. A direct injection engine control device comprising an expansion stroke injection command means. 9. The direct injection engine control device according to claim 1, wherein a compression stroke injection mode for performing fuel injection during a compression stroke can be set.