JP2021025409A - Control device of internal combustion engine - Google Patents

Abstract

To properly suppress a rise in an engine rotation number after a restart of an internal combustion engine.SOLUTION: A control device of an internal combustion engine is constituted such that, when a prescribed condition is established in which the blowup of an engine rotation number is concerned when restarting an internal combustion engine in an idling stop, correction control is performed to further reduce engine torque outputted by the internal combustion engine compared to the case of the non-establishment of the concerned prescribed condition. The correction control performs a fuel cut for, for example, temporarily pausing fuel injection and combustion in a part of cylinders out of a plurality of the cylinders which are possessed by the internal combustion engine, and continues the fuel injection and combustion in the other cylinders.SELECTED DRAWING: Figure 2

Description

The present invention relates to a control device that controls the operation of an internal combustion engine mounted on a vehicle or the like.

When starting an internal combustion engine that has been stopped, the crankshaft, which is the output shaft of the internal combustion engine, is rotationally driven by an electric motor, and fuel is injected from the injector to burn it in the cylinder, accelerating the rotation of the crankshaft. Perform cranking. Cranking is when the internal combustion engine goes from the first explosion to the continuous explosion and the rotation speed of the crankshaft, that is, the engine speed exceeds the complete explosion judgment value determined according to the cooling water temperature of the internal combustion engine, etc. (For example, see Patent Document 1 below).

It is also known that an idle stop system for stopping the idle rotation of the internal combustion engine is performed while the vehicle is stopped due to waiting for a traffic light or the like (see, for example, Patent Document 2 below). In the existing idling stop system, the vehicle speed is below the specified value, the brake pedal is depressed, the slope of the road surface where the vehicle is located is not large, the temperature of the internal combustion engine and the voltage of the in-vehicle battery are sufficiently high, etc. When all the conditions are met, the internal combustion engine is stopped. During idle stop, the internal combustion engine is restarted when the driver requests a restart such as releasing the brake pedal or depressing the accelerator pedal.

JP-A-2017-008865 JP-A-2016-113909

Compared to cold start, when restarting after idle stop, warm-up has already been completed and mechanical loss (friction loss) has been reduced, causing an excessive increase in engine speed. Cheap. When the engine speed rises, the passengers including the driver feel uncomfortable, and the number of fuel injections and combustions per unit time increases, resulting in an increase in fuel consumption. In order to further improve the fuel efficiency, it is important how to suppress the increase in the engine speed immediately after the start of the internal combustion engine.

In addition, it is also required to suppress the increase in emission _{of harmful substances, especially NO x} , immediately after the restart of the internal combustion engine.

In order to solve the above-mentioned problems, in the present invention, when restarting an internal combustion engine that has been idle-stopped, when a predetermined condition in which there is a concern that the engine speed may rise is satisfied, as compared with a case where it is not. A control device for an internal combustion engine that performs correction control for further reducing the engine torque output by the internal combustion engine is configured.

As the correction control, for example, fuel cut is executed in some cylinders of a plurality of cylinders provided in the internal combustion engine to suspend fuel injection and combustion, and fuel injection and combustion are continued in the other cylinders. ..

When the fuel cut is executed, it is preferable to correct the fuel injection amount in the cylinder in which the fuel injection and combustion are continued to be increased as compared with the case where the fuel cut is not executed.

Fuel that suspends fuel injection and combustion in all cylinders of the internal combustion engine when a predetermined condition that is considered to be unable to suppress the rise in engine speed is satisfied even if the correction control is performed. The cut is executed, and after the fuel cut is completed, the fuel injection amount in the cylinder is temporarily increased and corrected so that the air-fuel ratio becomes richer than the stoichiometric air-fuel ratio.

Further, as the correction control, ignition cut is executed in which combustion is temporarily suspended while continuing fuel injection in some of the plurality of cylinders provided in the internal combustion engine, and fuel injection and combustion are performed in the other cylinders. It is also conceivable to continue and to reduce the fuel injection amount in the cylinder that executes the ignition cut from the fuel injection amount in the cylinder that continues combustion without executing the ignition cut.

According to the present invention, it is possible to appropriately suppress an increase in the engine speed after restarting the internal combustion engine. In addition, it is possible to suppress an increase in emissions _{of harmful substances, especially NO x} , immediately after the restart of the internal combustion engine.

The figure which shows the schematic structure of the internal combustion engine and the control device in one Embodiment of this invention. The flow chart which shows the procedure example of the process which the control device of the internal combustion engine of the same embodiment executes according to a program. The flow chart which shows the procedure example of the process which the control device of the internal combustion engine which concerns on one of the modification of this invention executes according to a program.

An embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an outline of an internal combustion engine for a vehicle according to the present embodiment. The internal combustion engine of the present embodiment is a spark-ignition type 4-stroke engine, and includes a plurality of cylinders 1 (for example, four cylinders, one of which is illustrated in FIG. 1). An injector 11 for injecting fuel toward the intake port is provided upstream of the intake valve of each cylinder 1 and in the vicinity of the intake port connected to each cylinder 1. Further, a spark plug 12 is attached to the ceiling of the combustion chamber of each cylinder 1. The spark plug 12 receives the application of the induced voltage generated by the ignition coil and induces a spark discharge between the center electrode and the ground electrode. The ignition coil is integrally built in the coil case together with the igniter which is a semiconductor switching element.

The intake passage 3 for supplying intake air takes in air from the outside and guides it to the intake port of each cylinder 1. An air cleaner 31, an electronic throttle valve 32, a surge tank 33, and an intake manifold 34 are arranged in this order from the upstream on the intake passage 3.

The exhaust passage 4 for exhausting the exhaust guides the exhaust generated by burning the fuel in the cylinder 1 to the outside from the exhaust port of each cylinder 1. An exhaust manifold 42 and a three-way catalyst 41 for purifying exhaust gas are arranged on the exhaust passage 4.

Air-fuel ratio sensors 43 and 44 for detecting the air-fuel ratio of the gas flowing through the exhaust passage 4 are installed upstream and downstream of the catalyst 41 in the exhaust passage 4. The air-fuel ratio sensors 43 and 44 may be linear A / F sensors having output characteristics proportional to the air-fuel ratio of the exhaust gas, respectively, and are O ₂ sensors having output characteristics that are non-linear with respect to the air-fuel ratio of the exhaust gas. There may be.

The exhaust gas recirculation device 2 realizes a so-called high-pressure loop EGR, and is an external EGR that communicates the upstream side of the catalyst 41 in the exhaust passage 4 and the downstream side of the throttle valve 32 in the intake passage 3. The elements are a passage 21, an EGR cooler 22 provided on the EGR passage 21, and an EGR valve 23 that opens and closes the EGR passage 21 and controls the flow rate of EGR gas flowing through the EGR passage 21. The inlet of the EGR passage 21 is connected to the exhaust manifold 42 in the exhaust passage 4 or a predetermined position downstream thereof. The outlet of the EGR passage 21 is connected to a predetermined position downstream of the throttle valve 32 in the intake passage 3, specifically, the surge tank 33.

The internal combustion engine of the present embodiment is provided with a variable valve timing mechanism 5 capable of variably controlling at least the opening / closing timing of the intake valve of each cylinder 1. The intake VVT mechanism 5 is, for example, a vane type that changes the rotation phase of the intake camshaft that drives the intake valve of each cylinder 1 with respect to the crankshaft by hydraulic pressure (lubricating oil pressure), or an electric type that changes by an electric motor. (Motor drive VVT). As is well known, the intake camshaft and the exhaust camshaft receive rotational driving force from the crankshaft and rotate in accordance with the crankshaft. A winding transmission device for transmitting a rotational driving force is interposed between the crankshaft and the camshaft. The winding transmission device includes a crank sprocket (or pulley) provided on the crankshaft side, a cam sprocket (or pulley) provided on the camshaft side, and a timing chain (or belt) to be wound around these sprockets or pulleys. And as an element. The VVT mechanism 5 changes the rotation phase of the camshaft with respect to the crankshaft by rotating the camshaft relative to the camsprocket, thereby changing the opening / closing timing of the intake valve.

In addition, the internal combustion engine may be equipped with an exhaust VVT mechanism capable of variably controlling the opening / closing timing of the exhaust valve of each cylinder 1. The VVT mechanism for adjusting the exhaust valve timing also changes, for example, the rotation phase of the exhaust camshaft that drives the exhaust valve of each cylinder 1 with respect to the crankshaft by hydraulic pressure or an electric motor. This VVT mechanism may not exist, in which case the exhaust valve timing is invariant.

The ECU (Electronic Control Unit) 0, which is a control device for an internal combustion engine of the present embodiment, is a microcomputer system having a processor, a memory, an input interface, an output interface, and the like. The ECU 0 may be a plurality of ECUs or controllers connected to each other so as to be communicable with each other via a telecommunication line such as CAN (Control Area Network).

The input interface of ECU0 includes a vehicle speed signal a output from a vehicle speed sensor that detects the actual vehicle speed of the vehicle, a crank angle signal b output from a crank angle sensor that detects the rotation angle of the crank shaft and the engine rotation speed, and an accelerator pedal. Accelerator opening signal c output from a sensor that detects the amount of depression or the opening of the throttle valve 32 as the accelerator opening (so to speak, the required engine load factor or engine torque), in the surge tank 33 of the intake passage 3. The intake temperature / intake pressure signal d output from the temperature / pressure sensor that detects the intake temperature and intake pressure, the master cylinder pressure that is the pressure of the brake working fluid discharged from the sensor that detects the amount of depression of the brake pedal or the master cylinder. Brake depression signal e output from the sensor that detects, cooling water temperature signal f output from the water temperature sensor that detects the cooling water temperature that suggests the temperature of the internal combustion engine, to multiple cam angles of the intake cam shaft or exhaust cam shaft The cam angle signal g output from the cam angle sensor, the tilt angle (or acceleration) signal h output from the tilt angle sensor (or acceleration sensor) that detects the slope of the road surface on which the vehicle is located, and the catalyst 41. The air fuel ratio signal p output from the air fuel ratio sensor 43 that detects the air fuel ratio of the exhaust gas on the upstream side of the catalyst 41, and the air fuel ratio signal output from the air fuel ratio sensor 44 that detects the air fuel ratio of the exhaust gas on the downstream side of the catalyst 41. q etc. are input.

From the output interface, the ignition signal i for the igniter of the spark plug 12, the fuel injection signal j for the injector 11, the opening operation signal k for the throttle valve 32, and the opening operation signal l for the EGR valve 23. , The control signal m of the opening / closing timing of the intake valve is output to the VVT mechanism 5.

The processor of ECU 0 interprets and executes a program stored in the memory in advance, calculates an operation parameter, and controls the operation of the internal combustion engine. The ECU 0 acquires various information a, b, c, d, e, f, g, h, p, q necessary for the operation control of the internal combustion engine via the input interface, and determines the amount of air sucked into the cylinder 1. Required fuel injection amount (and can realize the target air-fuel ratio), fuel injection timing (including the number of fuel injections per combustion), fuel injection pressure, ignition timing, required EGR amount (or EGR) Rate), intake valve timing, and other operating parameters are determined. The ECU 0 applies various control signals i, j, k, l, and m corresponding to the operation parameters via the output interface.

The ECU 0 of the present embodiment executes an idle stop system for stopping the idle rotation of the internal combustion engine when a predetermined idle stop condition is satisfied. In ECU0, the brake pedal depression amount or master cylinder pressure is equal to or higher than a predetermined value (the brake pedal is depressed), the cooling water temperature of the internal combustion engine is higher than a predetermined value, and the charge amount or terminal voltage of the vehicle-mounted battery is equal to or higher than a predetermined value. The shift range is the driving range, the absolute value of the slope of the road surface where the vehicle is located is below the specified value, the magnitude of the negative pressure stored by the brake booster is above the specified value, and the previous idle. Idle because all the conditions such as having a history of accelerating to a certain vehicle speed (for example, 10 km / h) or more from the end of the stop and the current vehicle speed being less than a certain vehicle speed (for example, 9 km / h) are satisfied. It is judged that the stop condition is satisfied.

After the idle stop condition is satisfied, the internal combustion engine is restarted when the predetermined idle stop end condition is satisfied. In ECU0, the brake pedal depression amount or master cylinder pressure became 0 or less than the minimum value close to 0 (the brake pedal was not depressed), and conversely, the brake pedal depression amount or master cylinder pressure further increased (the brake pedal depression amount or master cylinder pressure was further increased). The brake pedal was depressed more strongly), the accelerator opening increased (the accelerator pedal was depressed), the magnitude of the negative pressure stored in the brake booster decreased to less than the specified value, and the specified time in the idle stop state. It is determined that the idle stop end condition is satisfied by any of the following (for example, 3 minutes) has passed.

When starting the stopped internal combustion engine (including not only the return from the idling stop but also the cold start), the ECU 0 inputs the control signal o to the electric motor (starter or ISG (Integrated Starter Generator), not shown). Then, while the crankshaft is rotationally driven by the electric motor, fuel is injected from the injector 11, spark ignition is performed by the ignition plug 12, and cranking is performed to burn the fuel. When the internal combustion engine goes from the first explosion to the continuous explosion and the engine speed exceeds the complete explosion judgment value, the cranking is considered to be complete and ends. The complete explosion determination value, which is the end condition of cranking, may fluctuate depending on the temperature of the internal combustion engine or the like. Basically, the lower the cooling water temperature of the internal combustion engine, the higher the complete explosion judgment value.

When restarting the internal combustion engine, as shown in FIG. 2, the ECU 0 of the present embodiment is compared with the case where a predetermined condition in which there is a concern about the engine speed rising is satisfied (step S1), as compared with the case where it is not. Correction control is performed to further reduce the engine torque output by the internal combustion engine (steps S2 to S4).

In step S1, for example, when the engine speed rises to a certain reference speed, the amount of increase in the engine speed per unit time is obtained, and the engine speed is subject to the condition that the increase exceeds the threshold value. It is judged that there is a concern that the engine speed will rise. Otherwise, it is judged that there is no concern about the engine speed rising. If the target value at which the engine speed should be converged after the internal combustion engine is completely detonated is, for example, 800 rpm, the above reference speed is set to a value lower than the target value during idle operation, for example, 500 rpm to 600 rpm.

As a specific example of the correction control, while executing fuel cut in which fuel injection and combustion are temporarily suspended in some cylinders 1 of the plurality of cylinders 1 provided in the internal combustion engine (step S2), the other cylinders 1 Then, fuel injection and combustion are continued (step S4). It is preferable that the fuel cuts in some cylinders 1 are performed at equal intervals as much as possible in order to suppress the vibration of the engine speed. For example, in a four-cylinder engine in which the expansion stroke is reached in the order of the first cylinder 1, the third cylinder 1, the fourth cylinder 1, and the second cylinder 1, the fuel is cut in the first cylinder 1 and the fourth cylinder 1. , Continue fuel injection and combustion in the third cylinder 1 and the second cylinder 1. Alternatively, fuel injection and combustion may be continued in the first cylinder 1 and the fourth cylinder 1 while the fuel is cut in the third cylinder 1 and the second cylinder 1. Regarding which one to select, the cylinder 1 in which the intake stroke or the fuel injection timing comes earliest after the condition in step S1 is satisfied, and the cylinder 1 paired with the cylinder 1 are the cylinders 1 that cut the fuel. Can be considered.

The number of cylinders 1 that execute fuel cut in steps S2 to S4, in other words, the number of cylinders 1 that continue fuel injection and combustion, is increased by increasing the engine speed per unit time when the conditions of step S1 are satisfied. It may be increased or decreased depending on the amount. If the increase in engine speed per unit time is relatively small, the number of cylinders 1 that perform fuel cuts can be reduced to, for example, only one. If the amount of increase in engine speed per unit time is relatively large, it is possible to increase the number of cylinders 1 that perform fuel cut, for example, three or more.

When the fuel cut of a part of the cylinder 1 in step S2 is executed, the amount of fuel injected from the injector 11 to the cylinder 1 that continues the fuel injection and combustion in step S4 is not executed. The amount is corrected more than the time (step S3). In the internal combustion engine of the present embodiment, the opening / closing operation of the intake valve and the exhaust valve driven by the intake / exhaust camshaft continues in the cylinder 1 that executes the fuel cut as well as the cylinder 1 that continues the fuel injection and combustion. Therefore, air containing no fuel component flows out from the cylinder 1 that executes the fuel cut toward the exhaust passage 4, and the air flows into the catalyst 41 for exhaust gas purification and is occluded in the catalyst 41. To increase the fuel injection amount in the cylinder 1 that continues fuel injection and combustion, the amount of oxygen stored in the catalyst 41 is reduced by supplying gas having a richer air-fuel ratio from the cylinder 1 to the catalyst 41. Therefore, the intention is to suppress the increase in the emission of harmful substance NO _x.

When the condition for ending the correction control is satisfied (step S5), the correction control is ended (step S6). That is, the fuel cut of a part of the cylinder 1 in step S2 is finished, the fuel injection and combustion in the cylinder 1 are restarted, and the fuel increase correction of the other cylinder 1 in step S4 is finished. The end condition of the correction control in step S5 is that the engine speed drops to a predetermined condition value without satisfying the condition of step S7, which will be described later, from the start of the control, and the condition of step S7 from the start of the control. The increase in engine speed per unit time fell below a predetermined amount without being established (or the increase in engine speed stopped or the engine speed began to decrease), or from the start of the control. A certain period of time has passed without satisfying the condition of step S7. It is preferable to set the above condition value to a value lower than the complete explosion determination value during cranking for starting the internal combustion engine and slightly higher than the target value during idle operation of the internal combustion engine.

If the condition of step S5 is not satisfied and a predetermined condition that it is considered that the engine speed cannot be suppressed even if the correction control is performed is satisfied (step S7), the internal combustion engine is provided. By executing the fuel cut in which the fuel injection and the combustion are temporarily suspended in all the cylinders 1 (step S8), the blow-up is surely suppressed.

When the condition for ending the fuel cut of all cylinders 1 is satisfied (step S9), the fuel cut is finished and fuel injection and combustion in all cylinders 1 are restarted (step S10). The end condition of the fuel cut control of all cylinders 1 in step S9 is that the engine speed has decreased to a predetermined condition value from the start of the control and the amount of increase in the engine speed per unit time from the start of the control. The amount has fallen below a predetermined amount (or the engine speed has stopped increasing or the engine speed has begun to decrease), or a certain period of time has passed since the start of the control. The above condition value may be set in the same manner as that in step S5.

Further, for a certain period after the fuel cut of all cylinders 1 is completed, the fuel injection amount in some or all cylinders 1 is temporarily set, and the air-fuel ratio of gas on the upstream side of the catalyst 41 is higher than the stoichiometric air-fuel ratio. The amount is increased and corrected so as to be rich (step S11). This is intended to reduce the amount of oxygen occluded in the catalyst 41 during the fuel cut of all cylinders 1 and suppress the increase in _{NO x emissions.} Even if the engine speed decreases due to the fuel cut of all the cylinders 1 in step S8 and the engine torque generated by increasing the fuel injection amount thereafter increases, the increase in the engine speed can be suppressed to a small extent.

In the present embodiment, when restarting an internal combustion engine that has been idle-stopped, when a predetermined condition in which there is a concern that the engine speed may rise is satisfied, the engine that the internal combustion engine outputs is compared with the case where it is not. A control device 0 for an internal combustion engine that performs correction control for further reducing torque is configured. According to the present embodiment, it is possible to appropriately suppress an unnecessary increase in the engine speed after restarting the internal combustion engine, maintain high drivability of the vehicle, and do not give a sense of discomfort to passengers including the driver. This makes it possible to suppress an increase in fuel consumption and further improve fuel efficiency.

In the present embodiment, as the correction control, fuel injection and combustion are temporarily suspended in some cylinders of the plurality of cylinders 1 provided in the internal combustion engine, and fuel injection and combustion are executed in the other cylinders 1. Continue burning. As a result, it is possible to suppress a sudden drop in the engine speed due to the fuel cut and a sudden increase in the engine speed due to the recovery from the fuel cut, start hunting of the engine speed, and smoothly shift to the target speed. At the same time, it also contributes to suppressing the increase in emission of _{harmful substance NO x.}

In addition, when the fuel cut is executed, the fuel injection amount in the cylinder 1 which continues the fuel injection and combustion is corrected to be larger than that when the fuel cut is not executed, so that the increase in NO _x emission is more effective. Can be deterred.

If a predetermined condition that it is considered that the engine speed cannot be suppressed even after the correction control is performed, fuel injection and combustion are temporarily suspended in all cylinders 1 of the internal combustion engine. Perform a fuel cut to ensure that the blow-up is stopped. Then, after the fuel cut is completed, the fuel injection amount in the cylinder 1 is temporarily increased and corrected so that the air-fuel ratio becomes richer than the stoichiometric air-fuel ratio, thereby suppressing the increase in _{NO x emissions.}

The present invention is not limited to the embodiments described in detail above. In particular, the content of the correction control for further reducing the engine torque when a predetermined condition in which the engine speed is concerned to rise is satisfied is not limited to that of the above embodiment.

For example, as shown in FIG. 3, the ECU 0, which is a control device for an internal combustion engine, is provided in the internal combustion engine as correction control when a predetermined condition in which there is a concern that the engine speed may rise is satisfied (step S1). While continuing fuel injection in some of the plurality of cylinders 1 and executing spark ignition, that is, ignition cut for suspending combustion (step S13), fuel injection and combustion are continued in the other cylinders 1. (Step S14). It is preferable that the ignition cuts in some cylinders 1 are performed at equal intervals as much as possible in order to suppress the vibration of the engine speed. For example, in a four-cylinder engine in which the expansion stroke is reached in the order of the first cylinder 1, the third cylinder 1, the fourth cylinder 1, and the second cylinder 1, fuel injection and ignition cut are performed in the first cylinder 1 and the fourth cylinder 1. Fuel injection and combustion are continued in the third cylinder 1 and the second cylinder 1 while performing the above. Alternatively, fuel injection and combustion may be continued in the first cylinder 1 and the fourth cylinder 1 while fuel injection and ignition cut are performed in the third cylinder 1 and the second cylinder 1. Regarding which one to select, the cylinder 1 in which the intake stroke or the fuel injection timing comes earliest after the condition in step S1 is satisfied, and the cylinder 1 paired with the cylinder 1 are set as the cylinder 1 for ignition cut. Can be considered.

The number of cylinders 1 that execute ignition cut in steps S12 to S14, in other words, the number of cylinders 1 that continue ignition combustion, is the amount of increase in engine speed per unit time when the condition of step S1 is satisfied. It may be increased or decreased depending on the amount. If the increase in engine speed per unit time is relatively small, the number of cylinders 1 that perform ignition cuts can be reduced to, for example, only one. If the amount of increase in engine speed per unit time is relatively large, it is possible to increase the number of cylinders 1 that perform ignition cut, for example, three or more.

When the ignition cut of some cylinders 1 in step S13 is executed, the fuel injection amount in the cylinder 1 that executes the ignition cut is corrected to be smaller than the fuel injection amount in the cylinder 1 that continues combustion without executing the ignition cut. (Step S12). Gas containing an unburned fuel component flows out from the cylinder 1 that executes the ignition cut toward the exhaust passage 4, and flows into the exhaust gas purification catalyst 41. The purpose of reducing the fuel injection amount in the cylinder 1 that cuts ignition is to suppress an increase in emission of harmful substances, particularly HC, by making the air-fuel ratio of the gas sent from the cylinder 1 to the catalyst 41 more lean.

As another example of correction control, operation of a valve or VVT mechanism 5 for reducing the engine torque by reducing the amount of air (and the amount of fuel) taken into the cylinder 1 from the intake passage 3 and ignition timing. It is conceivable that the air-fuel ratio of the air-fuel mixture filled in the cylinder 1 is greatly deviated from the stoichiometric air-fuel ratio to reduce or increase the fuel injection amount so as to cause a misfire. A plurality of types of correction controls may be combined.

In addition, the specific configuration of each part can be variously modified without departing from the spirit of the present invention.

The present invention can be applied to the control of an internal combustion engine mounted on a vehicle or the like.

0 ... Control device (ECU)
1 ... Cylinder 11 ... Injector 12 ... Ignition plug b ... Crank angle signal i ... Ignition signal j ... Fuel injection signal o ... Electric motor control signal for cranking

Claims (5)

When restarting an internal combustion engine that has been idle-stopped, the engine torque output by the internal combustion engine is further reduced when certain conditions are met that may cause the engine speed to rise. A control device for an internal combustion engine that performs correction control for the purpose. As the correction control, fuel cut is executed in a part of the plurality of cylinders included in the internal combustion engine to suspend fuel injection and combustion, and fuel injection and combustion are continued in the other cylinders. The control device for an internal combustion engine described. The control device for an internal combustion engine according to claim 2, wherein when the fuel cut is executed, the fuel injection amount in the cylinder that continues fuel injection and combustion is corrected to be increased as compared with the case where the fuel cut is not executed. Fuel cut that suspends fuel injection and combustion in all cylinders of the internal combustion engine when a predetermined condition that is considered to be unable to suppress the rise in engine speed is satisfied even if the correction control is performed. The control device for an internal combustion engine according to claim 1, 2 or 3, wherein, after the fuel cut is completed, the fuel injection amount in the cylinder is temporarily increased and corrected so that the air-fuel ratio becomes richer than the stoichiometric air-fuel ratio. .. As the correction control, ignition cut is executed in which combustion is temporarily suspended while continuing fuel injection in some of the plurality of cylinders provided in the internal combustion engine, and fuel injection and combustion are continued in the other cylinders. The control device for an internal combustion engine according to claim 1, wherein the fuel injection amount in the cylinder that executes the ignition cut is corrected to be smaller than the fuel injection amount in the cylinder that continues combustion without executing the ignition cut.

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