JP2023015516A - Control device of internal combustion engine - Google Patents

Abstract

To increase an output of an internal combustion engine while preventing an injection completion timing from shifting to a retard side with respect to a limit injection completion timing.SOLUTION: An E/G-ECU 100 performs calculation to increase an injection timing correction amount Qh (S23), when an injection completion timing Te is shifted to a retard angle side with respect to a prescribed crank angle Tcm (YES in S22). Thus, a target injection amount Qf is reduced, an injection period Tp is shortened, and the injection completion timing Te is prevented from shifting to a retard angle side with respect to a limit injection completion timing Cm. As a result, a fuel injection amount can be increased in comparison with a conventional one, and an output of the internal combustion engine 1 can be increased.SELECTED DRAWING: Figure 5

Description

TECHNICAL FIELD The present disclosure relates to a control device for an internal combustion engine, and more particularly to a control device for a compression self-ignition internal combustion engine.

2. Description of the Related Art Compression self-ignition internal combustion engines, such as diesel engines, are known in which fuel injected into a combustion chamber from a fuel injection valve is burned by self-ignition. For example, Japanese Patent Application Laid-Open No. 11-159385 calculates the fuel injection period from the detected values of the fuel injection start timing and the injection end timing, calculates the ignition delay period from the detected values of the fuel injection start timing and the combustion start timing, Diesel capable of reducing NOx (nitrogen oxide) and PM (particulate matter) by increasing and correcting the fuel injection pressure so that the fuel injection period is shorter when the ignition delay period is shorter than the fuel injection period An engine is disclosed.

JP-A-11-159385

As the amount of fuel injected from the fuel injection valve increases, the fuel injection period lengthens. As the fuel injection period becomes longer, the injection end timing advances to the retarded side of the crank angle. If the injection end timing advances to the retarded side, problems such as an increase in exhaust temperature and an increase in the amount of soot mixed into the lubricating oil will occur.

Injection characteristics of fuel injection valves vary, and the injection characteristics change due to deterioration. For this reason, we conduct experiments in advance to determine the crank angle at the injection end timing (limit injection end timing) at which problems such as an increase in exhaust temperature and soot contamination in the lubricating oil begin to occur. The fuel injection amount is set so that the injection end timing falls within the limit injection end timing (so that the injection end timing is not retarded from the limit injection end timing), taking into account variations in the injection characteristics and changes in characteristics. .

In this way, since the fuel injection amount is set in consideration of variations in the injection characteristics of the fuel injection valve and characteristic changes, the magnitude of the fuel injection amount is limited, and the output of the internal combustion engine is not the output that should be obtained. There is a problem of lowering Patent Document 1 does not disclose this point.

An object of the present disclosure is to make it possible to increase the output of an internal combustion engine while keeping the injection end timing within the limit injection end timing (preventing the injection end timing from being retarded from the limit injection end timing). .

A control device for an internal combustion engine of the present disclosure is a control device for a compression self-ignition internal combustion engine having a fuel injection valve that injects fuel into a combustion chamber. The control device includes an injection end timing acquisition unit that acquires an injection end timing at which the fuel injection by the fuel injection valve ends, and an injection amount that reduces the fuel injection amount when the injection end timing is retarded from a predetermined crank angle. and a calculator.

According to this configuration, the injection amount calculator reduces the fuel injection amount when the injection end timing acquired by the injection end timing acquisition unit is retarded relative to the predetermined crank angle. The injection end timing is acquired, and when the acquired injection end timing is on the retard side of the predetermined crank angle, the fuel injection amount is reduced. Even if the fuel injection amount is not set, the injection end timing can be kept within the limit injection end timing (it is possible to prevent the injection end timing from being retarded from the limit injection end timing), and the internal combustion engine output can be increased.

Preferably, the injection amount calculation unit may be configured to correct the basic injection amount calculated according to the load to decrease when the injection end timing is retarded relative to the predetermined crank angle.

According to this configuration, it is possible to bring the injection end timing within the limit injection end timing by a simple technique of decreasing the basic injection amount.

Preferably, the injection amount calculation unit calculates the basic injection amount according to the load from a map stored in advance, and rewrites the map when the injection end timing is retarded from the predetermined crank angle. It may be configured to reduce the fuel injection amount.

According to this configuration, since the fuel injection amount is reduced by rewriting the map for calculating the basic injection amount, it is possible to obtain a map that takes into account changes in the characteristics of the fuel injection valve.

Preferably, the predetermined crank angle may be a crank angle at which the amount of soot mixed into the lubricating oil becomes equal to or greater than a predetermined value when the injection end timing advances to the retarded side relative to the predetermined crank angle.

According to this configuration, the fuel injection amount can be set large within a range in which the injection end timing can be within the limit injection end timing, and the output of the internal combustion engine can be increased.

Preferably, the predetermined crank angle is advanced by the set crank angle with respect to the crank angle at which the amount of soot mixed into the lubricating oil reaches a predetermined value or more when the injection end timing advances to the retard side of the predetermined crank angle. may be the crank angle of

According to this configuration, since the fuel injection amount is set with a margin corresponding to the set crank angle, the injection end timing can be reliably set within the limit injection end timing even if there is variation in the accuracy of the injection end timing acquisition unit. be able to.

According to the present disclosure, it is possible to increase the output of the internal combustion engine while keeping the injection end timing within the limit injection end timing.

1 is an overall configuration diagram of an internal combustion engine according to an embodiment; FIG. FIG. 5 is a diagram showing the relationship between the injection end timing and the amount of soot mixed in lubricating oil. 4 is a diagram showing the relationship between the fuel injection amount and the injection end timing when the internal combustion engine 1 is running at full load; FIG. 4 is a flowchart showing fuel injection control processing executed by the E/G-ECU 100. FIG. 4 is a flowchart showing correction amount calculation control processing executed by the E/G-ECU 100. FIG. FIG. 3 is a diagram showing the relationship between the fuel injection amount and the injection end timing during full-load operation of the internal combustion engine 1 in the present embodiment. 4 is a flowchart showing processing of basic injection amount update control executed by E/G-ECU 100 in a modified example;

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The same or corresponding parts in the drawings are denoted by the same reference numerals, and the description thereof will not be repeated.

FIG. 1 is an overall configuration diagram of an internal combustion engine according to this embodiment. The internal combustion engine 1 is a diesel engine that injects fuel from a fuel injection valve (injector) 14 into a combustion chamber formed in a cylinder (cylinder) 12 of an engine body 10 to perform compression self-ignition. An intake passage 20 of the internal combustion engine 1 is provided with an air cleaner 22, an intercooler 24, and an intake throttle valve (electronic control throttle) 26. It is supercharged (compressed) by the compressor 32 of the feeder 30, cooled by the intercooler 24, supplied to the intake manifold 28, and supplied to each combustion chamber from the intake port.

In this embodiment, the fuel injection system employs a common rail type fuel injection system (accumulator type fuel injection device). The high-pressure fuel is injected from the fuel injection valve 14 into the combustion chamber.

The fuel injection valve 14 includes a fuel injection nozzle that injects fuel into the combustion chamber, a piezoelectric element that drives a nozzle needle accommodated in the fuel injection nozzle in the valve opening direction, and a spring that biases the nozzle needle in the valve closing direction. The fuel injection is controlled by energizing and stopping the energization (ON/OFF) of the piezoelectric element. While the piezoelectric element is energized and the nozzle needle opens a plurality of injection holes formed at the tip of the nozzle body, high-pressure fuel accumulated in the common rail 42 is injected into the combustion chamber. The fuel injection valve 14 is provided with a fuel pressure sensor 16 for detecting the fuel pressure in the fuel passage from the common rail 42 to the injection hole. It should be noted that an electromagnetic solenoid or the like may be used to drive the nozzle needle to open the valve.

Exhaust gas (exhaust gas) discharged from the combustion chamber is collected in an exhaust manifold 50 and released to the outside air through an exhaust passage 52 . The exhaust passage 52 is provided with a turbine 34 of the turbocharger 30, an oxidation catalyst 70, a DPF (Diesel Particulate Filter) 72, a selective reduction catalyst 74, and an oxidation catalyst 76 from the upstream side. The oxidation catalyst 70 oxidizes carbon monoxide (CO) in the exhaust to carbon dioxide (CO2) and hydrocarbons (HC) in the exhaust to water ( _H2O ) and _CO2 . It also oxidizes nitrogen monoxide (NO) in the exhaust gas to nitrogen dioxide (NO ₂ ).

The DPF 72 purifies the exhaust gas by collecting particulates in the exhaust gas and appropriately burning and removing the particulates. A selective reduction catalyst (hereinafter also referred to as an SCR (Selective Catalytic Reduction) catalyst) 74 reduces and purifies NOx in exhaust gas. The oxidation catalyst 76 oxidizes and purifies the ammonia discharged (slipped) from the SCR catalyst 74 .

A urea addition valve (urea water injection injector) 80 is provided in the exhaust passage upstream of the SCR catalyst 74, and urea water pressure-fed from a urea water tank 82 by a pump (not shown) is injected from the urea addition valve 80 into the SCR catalyst 74. is injected into the exhaust passage 52 upstream of the . The urea water supplied to the exhaust passage upstream of the SCR catalyst 72 is hydrolyzed to produce ammonia, which is used as a reducing agent to reduce and purify NOx.

In this embodiment, an E/G-ECU (Electronic Control Unit) 100 is provided as a control device for the internal combustion engine 1 . The E/G-ECU 100 includes a CPU (Central Processing Unit) 101, a ROM (Read Only Memory) for storing processing programs and the like, a memory 102 such as a RAM (Random Access Memory) for temporarily storing data, and various signals. Based on information stored in memory (ROM and RAM) 102 and information from various sensors, the fuel injection valve 14 includes input/output ports (not shown) for output. etc.

Various sensors are, for example, a fuel pressure sensor 16, an accelerator opening sensor 121, a crank angle sensor 122, a cooling water temperature sensor 123, and the like. The fuel pressure sensor 16 detects the fuel pressure P within the fuel passage from the common rail 42 to the injection holes. The accelerator opening sensor 121 detects an accelerator pedal operation amount (accelerator opening) AP. A crank angle sensor 122 detects a crank angle CA of the internal combustion engine 1 . A coolant temperature sensor 123 detects a coolant temperature THW of the internal combustion engine 1 .

As the amount of fuel injected from the fuel injection valve 14 increases, the fuel injection period (valve opening period of the fuel injection valve 14) becomes longer. As the fuel injection period becomes longer, the injection end timing advances to the retarded side of the crank angle. FIG. 2 is a diagram showing the relationship between the injection end timing and the amount of soot mixed in lubricating oil. In FIG. 2, the horizontal axis indicates the injection end timing, which indicates the crank angle (CA) after top dead center (ATDC). The vertical axis indicates the soot concentration of the lubricating oil. As shown, when the injection end timing is retarded relative to the crank angle Cm, the lubricating oil soot concentration (amount of soot in the oil) increases, and when the injection end timing is retarded, the exhaust temperature rises. The crank angle Cm at which the soot amount in oil starts to increase is also referred to as limit injection end timing Cm.

FIG. 3 is a diagram showing the relationship between the fuel injection amount and the injection end timing when the internal combustion engine 1 is running at full load. In FIG. 3, the upper part shows the injection command for the fuel injection valve 14. When the injection command is ON, the piezoelectric element is energized, the injection hole of the fuel injection valve 14 is opened, and the fuel is injected. In FIG. 3, the lower part shows the injection rate of fuel injection. In the example shown in FIG. 3, two-stage injection of pilot injection and main injection is performed, and pilot injection is performed first, followed by main injection. When the injection command is turned ON and the piezoelectric element is energized, fuel is injected from the injection hole after an injection delay, and when the injection command is turned OFF and the energization is stopped, the fuel injection stops with a delay. In the lower part of FIG. 3, the area surrounded by the injection rate corresponds to the fuel injection amount.

The greater the fuel injection amount, the greater the power output the internal combustion engine 1 can generate. Therefore, when the internal combustion engine 1 is operating at full load, such as during WOT (Wide Open Throttle), it is desirable to increase the fuel injection amount as much as possible. However, the injection characteristics of the fuel injection valve 14 vary, and the injection characteristics change due to deterioration. For this reason, the injection period ( The energization period) Tp is obtained, and the fuel injection amount during full-load operation is set. As a result, even if the injection characteristics of the fuel injection valve 14 fluctuate or change, the injection end timing is kept within the limit injection end timing Cm (so that the injection end timing does not become retarded from the limit injection end timing Cm). , the fuel injection amount can be set.

When the fuel injection amount is set in this manner, the fuel injection amount is limited by the fuel injection amount corresponding to the margin A, as shown in the shaded area in FIG. The output decreases, and the performance of the internal combustion engine 1 cannot be effectively utilized.

In the present embodiment, the injection end timing is acquired, and in a state where the injection end timing is retarded from the limit injection end timing Cm, the fuel injection amount is decreased to set the injection end timing to the limit injection end timing. The output of the internal combustion engine 1 can be increased while keeping the injection end timing within Cm (preventing the injection end timing from being retarded from the limit injection end timing Cm).

FIG. 4 is a flowchart showing the fuel injection control process executed by the E/G-ECU 100. As shown in FIG. This flow chart is repeatedly processed while the internal combustion engine 1 is operating (after the ignition switch is turned on until the ignition switch is turned off). In step (hereinafter step is abbreviated as S) 10, it is determined whether or not the DPF 72 is being regenerated. During the regeneration of the DPF 72, which burns and removes the fine particles collected by the DPF 72, the fuel injection timing is retarded and the exhaust stroke injection or the like is performed to increase the exhaust gas temperature. It will be on the lag side. Therefore, if the DPF 72 is being regenerated and an affirmative determination is made in S10, the current routine is terminated. (In this case, a fuel injection control process for regeneration of the DPF 72 is executed separately.) If the DPF 72 is not being regenerated, a negative determination is made and the process proceeds to S11.

In S11, the number of injection stages is calculated based on the accelerator opening AP and the engine rotation speed NE. Note that the engine rotation speed NE can be calculated based on the crank angle CA detected by the crank angle sensor 122 .

In subsequent S12, a basic injection amount Q is calculated based on the accelerator opening AP and the engine rotation speed NE. The basic injection amount Q is stored in the memory 102 as a map using the accelerator opening AP and the engine rotation speed NE as parameters. Note that when the number of injection stages and the basic injection amount are specified in the optimum injection map using the accelerator opening AP and the engine rotation speed NE as parameters, S11 and S12 may be processed at the same time.

At S13, a target injection amount Qf is calculated. For example, the target injection amount Qf is calculated as "target injection amount Qf=Q+Qt+Qa-Qh". Here, Qt is a warm-up correction amount, which is calculated based on the cooling water temperature THW. Qa is an acceleration correction amount, which is calculated based on the change amount ΔAP of the accelerator opening AP. Qh is an injection timing correction amount, which is calculated by correction amount calculation control (FIG. 5), which will be described later. After the internal combustion engine 1 has been warmed up, the "warm-up correction amount Qt=0" is set, and when the change amount ΔAP of the accelerator opening AP is less than or equal to a predetermined value, the "acceleration correction amount Qa=0" is set. be.

At S14, the injection start timing T is calculated from the engine speed NE and the target injection amount Qf. Then, in S15, the injection period (energization period) Tp is calculated based on the fuel pressure Pc in the common rail 42, the engine speed NE, and the target injection amount Qf, and the current routine ends.

When the injection start time T and the injection period Tp are calculated by the fuel injection control process, the injection command is turned ON from the injection start time T until the injection period Tp ends. As a result, the driving actuator (piezoelectric element, etc.) of the fuel injection valve 14 is energized through the injection valve driving circuit (not shown) while the injection command is ON, and the fuel is injected from the fuel injection valve 14. be done. The injection start timing T and the injection period Tp are calculated for each injection stage, and the distribution ratio of the target injection amount Qf to each injection stage is included (as information) in the number of injection stages calculated in S11. good.

In S12, the basic injection amount Q is calculated based on the accelerator opening AP and the engine rotation speed NE, but the basic injection amount Q may be calculated by so-called torque demand control. For example, the required shaft torque is calculated from the accelerator opening AP and the engine rotation speed NE, and the required indicated torque (combustion pressure torque) is obtained by adding the consumption torque of the internal combustion engine 1 to this required shaft torque. The basic injection amount Q may be calculated based on the torque. In either case, the basic injection amount Q corresponding to the load of the internal combustion engine 1 is calculated.

FIG. 5 is a flowchart showing correction amount calculation control processing executed by the E/G-ECU 100. As shown in FIG. This flow chart is repeatedly processed while the internal combustion engine 1 is operating. At S20, it is determined whether the DPF 72 is being regenerated. If the DPF 72 is being regenerated, the determination is affirmative, and the current routine ends. If the DPF 72 is not being regenerated, a negative determination is made and the process proceeds to S21.

In S21, the injection end timing Te is acquired. In the present embodiment, the fuel pressure P in the fuel passage from the common rail 42 to the injection hole detected by the fuel pressure sensor 16 is used to calculate the injection end timing Te. For example, the injection end timing Te is calculated based on the timing at which the differential value of the fuel pressure P reaches a maximum when the fuel pressure P rises due to the injection command being turned off. Since the method of calculating the injection end timing Te using the differential value of the fuel pressure P is well known, detailed description thereof will be omitted. (For example, see Japanese Patent Application Laid-Open No. 2019-65721)
In subsequent S22, it is determined whether or not the injection end timing Te acquired in S21 is equal to or greater than a predetermined crank angle Tcm. In the present embodiment, the injection end timing Te obtained in S21 is obtained as the value of the ATDC crank angle CA. is on the retarded side. It should be noted that the predetermined crank angle Tcm is a value that is advanced by the margin a with respect to the limit injection end timing Cm. The margin a is set, for example, in consideration of variations in the calculation of the injection end timing Te, and is set in advance by experiment or the like as a value smaller than the margin A in FIG.

If the injection end timing Te is equal to or greater than the predetermined crank angle Tcm, and if the injection end timing Te is retarded by the predetermined crank angle Tcm or more, an affirmative determination is made in S22 and the process proceeds to S23. If the injection end timing Te is less than the predetermined crank angle Tcm and is on the advance side of the predetermined crank angle Tcm, a negative determination is made in S22 and the process proceeds to S24.

In S23, a predetermined value α is added to the injection timing correction amount Qh, and the current routine ends. In S24, it is determined whether or not the injection timing correction amount Qh is 0 or less. In S24, if the injection timing correction amount Qh is greater than 0, a negative determination is made and the process proceeds to S15.

At S25, a predetermined value β is subtracted from the injection timing correction amount Qh, and the current routine ends. In S26, the injection timing correction amount Qh is set to 0, and the current routine ends.

In the present embodiment, in the correction amount calculation control, when the injection end timing Te is on the retard side of the predetermined crank angle Tcm or more, the injection timing correction amount Qh is calculated to be large (S23). In the fuel injection control, the target injection amount Qf is calculated by subtracting the injection timing correction amount Qh from the basic injection amount Q (S13). Therefore, when the injection end timing Te is retarded relative to the predetermined crank angle Tcm, the target injection amount Qf is decreased and the injection period Tp is shortened. Then, when the injection period Tp becomes shorter and the injection end timing Te becomes more advanced than the predetermined crank angle Tcm, the injection timing correction amount Qh is calculated to become smaller and finally set to 0 (S24 to S26). .

FIG. 6 is a diagram showing the relationship between the fuel injection amount and the injection end timing during full-load operation of the internal combustion engine 1 according to the present embodiment. In FIG. 6, the upper part shows the injection command for the fuel injection valve 14, and the lower part shows the injection rate of the fuel injection. In this embodiment, when the injection end timing Te is retarded from the predetermined crank angle Tcm, the target injection amount Qf is decreased to shorten the injection period Tp. Therefore, as shown in FIG. 6, even if the predetermined crank angle Tcm is set by making the margin a smaller than the margin A (see FIG. 3), which takes into account variations in the injection characteristics of the fuel injection valve 14 and changes in characteristics. , the injection end timing Te can be set within the limit injection end timing Cm (the injection end timing can be prevented from being delayed from the limit injection end timing Cm). Therefore, even if the fuel injection amount is not set in consideration of variations in the injection characteristics of the fuel injection valve 14 and characteristic changes, the fuel injection amount is limited by the fuel injection amount corresponding to the margin a (see the shaded area in FIG. 6). Since the fuel injection amount can be increased compared to the conventional art, the output of the internal combustion engine 1 can be increased, and the performance of the internal combustion engine 1 can be effectively utilized.

In the above-described embodiment, the margin a is set in consideration of variations in calculation of the injection end timing Te. However, when the calculation accuracy of the injection end timing Te is high, the margin a may be set to 0 (the margin a may be omitted). For example, if a stroke sensor (displacement sensor) is provided in the nozzle needle of the fuel injection valve 14 to detect that the nozzle needle has closed the injection hole, the injection end timing Te can be detected with high accuracy. In this case, the margin a may be set to 0, and the predetermined crank angle Tcm may be set as the limit injection end timing Cm. Even in this case, the predetermined crank angle Tcm may be set using a margin that is smaller than the margin a in consideration of control variations in fuel injection control.

(Modification)
In the above embodiment, the target injection amount Qf is obtained by calculating the injection timing correction amount Qh and correcting the basic injection amount Q to decrease. However, the configuration for decreasing the fuel injection amount (target injection amount Qf) is not limited to this.

FIG. 7 is a flowchart showing processing of basic injection amount update control executed by the E/G-ECU 100 in the modified example. This flow chart is repeatedly processed while the internal combustion engine 1 is operating. At S30, it is determined whether or not the DPF 72 is being regenerated. If the DPF 72 is being regenerated, the determination is affirmative, and the current routine ends. If the DPF 72 is not being regenerated, a negative determination is made and the process proceeds to S31.

In S31, similarly to S21 in FIG. 6, the injection end timing Te is acquired, and then the process proceeds to S32. In S32, it is determined whether or not the injection end timing Te is equal to or greater than a predetermined crank angle Tcm. If the injection end timing Te is less than the predetermined crank angle Tcm and is on the advance side of the predetermined crank angle Tcm, a negative determination is made in S32, and the current routine ends.

If the injection end timing Te is equal to or greater than the predetermined crank angle Tcm, and if the injection end timing Te is retarded by the predetermined crank angle Tcm or more, an affirmative determination is made in S32 and the process proceeds to S33. At S33, a new basic injection amount Q is calculated by subtracting a predetermined value γ from the basic injection amount Q for the fuel injection at the injection end timing Te acquired at S31. Then, in the map for calculating the basic injection amount, the value of the corresponding basic injection amount Q is rewritten with a new value of the basic injection amount Q, the map is updated, and then the current routine ends.

Also in this modification, fuel injection is performed from the fuel injection valve 14 by the fuel injection control of FIG. Note that in the modified example, the injection timing correction amount Qh is not calculated, so in S13 the target injection amount Qf is calculated as "Qf=Q+Qt+Qa."

According to this modification, when the injection end timing Te is retarded from the predetermined crank angle Tmc, the corresponding basic injection amount Q is rewritten to a new basic injection amount Q in the map for calculating the basic injection amount. As a result, the basic injection amount Q becomes a small value. Therefore, when the injection end timing Te is retarded relative to the predetermined crank angle Tcm, the target injection amount Qf is decreased and the injection period Tp is controlled to be shortened. . Further, the value of the basic injection amount Q when the injection end timing Te is retarded beyond the predetermined crank angle Tcm is rewritten to a smaller value and the map is updated. You can get a modified map. Since the updated map is used to calculate the basic injection amount Q, it is possible to prevent the injection end timing Te from becoming retarded relative to the predetermined crank angle Tmc.

In the above-described embodiment and modified example, when the DPF 72 is not being regenerated, it is determined whether or not the injection end timing Te is on the retard side of the predetermined crank angle Tmc, and correction for decreasing the fuel injection amount is performed. rice field. The injection end timing Te is delayed from the predetermined crank angle Tmc only when the load on the internal combustion engine 1 is large and the fuel injection amount is large. Therefore, in addition to the condition that the DPF 72 is not being regenerated, when the load of the internal combustion engine 1 is high, for example, when the condition "when the accelerator opening AP is a predetermined value (for example, 90%) or more" is satisfied, It may be determined whether or not the injection end timing Te is retarded from the predetermined crank angle Tmc.

The embodiments disclosed this time should be considered as examples and not restrictive in all respects. The scope of the present invention is indicated by the scope of the claims rather than the description of the above-described embodiments, and is intended to include all modifications within the scope and meaning equivalent to the scope of the claims.

1 internal combustion engine, 10 engine body, 12 cylinder (cylinder), 14 fuel injection valve, 16 fuel pressure sensor, 20 intake passage, 22 air cleaner, 24 intercooler, 26 intake throttle valve, 28 intake manifold, 30 turbocharger, 32 compressor, 34 turbine, 40 fuel tank, 41 high-pressure pump, 42 common rail, 50 exhaust manifold, 52 exhaust passage, 54 bypass passage, 70 oxidation catalyst, 72 DPF, 74 selective reduction catalyst (SCR catalyst), 76 oxidation catalyst, 80 Urea addition valve, 82 urea water tank, 100 E/G-ECU, 101 CPU, 102 memory, 121 accelerator opening sensor, 122 crank angle sensor, 123 cooling water temperature sensor.

Claims (5)

A control device for a compression self-ignition internal combustion engine having a fuel injection valve that injects fuel into a combustion chamber,
The control device is
an injection end timing obtaining unit that obtains an injection end timing at which the fuel injection by the fuel injection valve is finished;
A control device for an internal combustion engine, comprising: an injection amount calculation unit that reduces a fuel injection amount when the injection end timing is retarded relative to a predetermined crank angle. 2. The injection quantity calculation unit according to claim 1, wherein the injection end timing is configured to decrease and correct the basic injection quantity calculated according to the load when the injection end timing is retarded from the predetermined crank angle. internal combustion engine controller. The injection amount calculation unit calculates a basic injection amount according to the load from a map stored in advance, and rewrites the map when the injection end timing is retarded from the predetermined crank angle. 2. The control device for an internal combustion engine according to claim 1, wherein said control device is configured to decrease said fuel injection amount. The predetermined crank angle is a crank angle at which the mixture of soot into the lubricating oil becomes equal to or greater than a predetermined value when the injection end timing advances to the retard side of the predetermined crank angle. The control device for an internal combustion engine according to any one of claims 1 to 3. The predetermined crank angle is advanced by a set crank angle with respect to the crank angle at which the mixture of soot in the lubricating oil reaches a predetermined value or more when the injection end timing advances to the retard side of the predetermined crank angle. 4. The control device for an internal combustion engine according to claim 1, wherein the crank angle is .

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