JP2008157050A - Control device for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology for stabilizing an EGR rate of intake introduced into a cylinder to keep a favorable combustion state of an internal combustion engine in a control device of the internal combustion engine. <P>SOLUTION: When pulse supercharging is carried out by using an opening/closing valve for pulse supercharging, using a high pressure EGR passage to reflux high pressure EGR gas is prohibited and an EGR gas amount required by the internal combustion engine is supplied by refluxing low pressure EGR gas by using a low pressure EGR passage(S102). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a control device for an internal combustion engine.

An internal combustion engine mounted on a vehicle or the like is provided with an EGR passage that recirculates a part of exhaust gas (EGR gas) discharged from the internal combustion engine to an exhaust passage to the intake passage of the internal combustion engine. And the EGR driving | running which reduces the discharge | emission amount of NOx by lowering | hanging the combustion temperature of an internal combustion engine with the gas recirculated from the EGR channel | path is implemented (for example, refer patent document 1).
JP 2002-349358 A JP-A-8-135518 JP 2006-118369 A

  By the way, in recent years, a pulse supercharging on / off valve has been provided in the intake passage upstream of the intake valve of the internal combustion engine, and the pulse supercharging on / off valve is used for a sudden increase in intake air amount, such as during acceleration operation. An internal combustion engine for supercharging has been proposed.

  Here, when the EGR passage is provided as in the prior art described above, the EGR gas supply port in which the EGR passage is connected to the intake passage may be disposed in the vicinity of the on / off valve for pulse supercharging. In this case, if pulse supercharging is performed while performing EGR operation, EGR gas excessively flows into the internal combustion engine from the EGR passage due to pulse supercharging. And the ratio (EGR rate) of the EGR gas amount with respect to the intake air introduced into the cylinder changes, and the combustion state of the internal combustion engine is deteriorated.

  An object of the present invention is to provide a technique for stabilizing an EGR rate of intake air introduced into a cylinder and maintaining a good combustion state of the internal combustion engine in an internal combustion engine control device.

In the present invention, the following configuration is adopted. That is,
A turbocharger having a turbine disposed in an exhaust passage of an internal combustion engine and a compressor disposed in an intake passage of the internal combustion engine;
A low pressure EGR passage that takes a part of exhaust gas as low pressure EGR gas from the exhaust passage downstream of the turbine and recirculates the low pressure EGR gas to the intake passage upstream of the compressor;
A high-pressure EGR passage that takes a part of the exhaust as high-pressure EGR gas from the exhaust passage upstream of the turbine and recirculates the high-pressure EGR gas to the intake passage downstream of the compressor;
An on / off valve for pulse supercharging provided in the intake passage downstream of the compressor and upstream of the intake valve of the internal combustion engine;
A first control means for prohibiting recirculation of the high-pressure EGR gas using the high-pressure EGR passage when performing pulse supercharging using the pulse-supercharging on-off valve;
A control device for an internal combustion engine, comprising:

In recent years, an on / off valve for pulse supercharging has been provided in the intake passage downstream of the compressor and upstream of the intake valve of the internal combustion engine, and the on / off valve for pulse supercharging is provided when a sudden increase in the amount of intake air is required, such as during acceleration operation. There has been proposed an internal combustion engine that is used for pulse supercharging. Pulse supercharging is a supercharging method that increases the inertial supercharging effect of intake air by making the valve opening period of the pulse supercharging on / off valve different from the valve opening period of the intake valve, and is sometimes referred to as impulse supercharging.

  The operation of the on / off valve for pulse supercharging (pulse supercharging operation) in the pulse supercharging is, for example, an operation of closing the valve before starting the opening of the intake valve and opening the valve before starting the closing of the intake valve.

  According to such pulse supercharging, the intake passage between the pulse supercharging on-off valve and the intake valve is in a period from the opening start timing of the intake valve to the opening start timing of the pulse supercharging on-off valve. Negative pressure is generated by the downward movement of the piston. Therefore, when the pulse supercharging on / off valve is opened, the gas upstream of the pulse supercharging on / off valve rapidly flows into the intake passage between the pulse supercharging on / off valve and the intake valve and the internal combustion engine. It becomes like this. As a result, the inertial supercharging effect of intake air is increased, and the gas charging efficiency in the cylinder is improved.

  The above-described pulse supercharging is mainly used to compensate for the turbocharger supercharging delay (turbo lag) during acceleration operation of an internal combustion engine equipped with a turbocharger.

  Here, when the internal combustion engine is provided with a high pressure EGR passage, the high pressure EGR gas supply port connected to the intake passage is downstream of the compressor and is arranged in the vicinity of the pulse supercharging on / off valve. Is done. In this case, if pulse supercharging is performed while performing EGR operation using the high pressure EGR passage, the high pressure EGR gas excessively flows into the internal combustion engine from the high pressure EGR passage due to the pulse supercharging. Then, the EGR rate of the intake air introduced into the cylinder changes, and the combustion state of the internal combustion engine is deteriorated.

  Therefore, in the present invention, when the pulse supercharging is performed using the pulse supercharging on / off valve, it is prohibited to recirculate the high pressure EGR gas using the high pressure EGR passage.

  According to this, since the high pressure EGR gas is not recirculated during the pulse supercharging, the high pressure EGR gas does not flow into the internal combustion engine from the high pressure EGR passage.

  On the other hand, it is necessary to supply EGR gas to the internal combustion engine according to the operating state of the internal combustion engine. Here, in the low pressure EGR passage, the supply port of the low pressure EGR gas connected to the intake passage is upstream of the compressor. For this reason, it is not affected by pulse supercharging. Therefore, the amount of EGR gas to be introduced into the cylinder can be stably supplied by the EGR operation using the low pressure EGR passage.

  That is, the first control means prohibits recirculation of the high pressure EGR gas using the high pressure EGR passage when pulse supercharging is performed using the pulse supercharging on / off valve, and the internal combustion engine is The required amount of EGR gas may be supplied by refluxing the low pressure EGR gas using the low pressure EGR passage.

  Therefore, the pulse supercharging and the EGR operation using the low pressure EGR passage are simultaneously performed, the EGR rate of the intake air introduced into the internal combustion engine is stabilized, and the combustion state of the internal combustion engine can be kept good.

In the present invention, the following configuration is adopted. That is,
A turbocharger having a turbine disposed in an exhaust passage of an internal combustion engine and a compressor disposed in an intake passage of the internal combustion engine;
A low pressure EGR passage that takes in a part of exhaust gas as low pressure EGR gas from the exhaust passage downstream of the turbine and recirculates the low pressure EGR gas to the intake passage upstream of the compressor;
A high-pressure EGR passage that takes a part of the exhaust as high-pressure EGR gas from the exhaust passage upstream of the turbine and recirculates the high-pressure EGR gas to the intake passage downstream of the compressor;
An on / off valve for pulse supercharging provided in the intake passage downstream of the compressor and upstream of the intake valve of the internal combustion engine;
A second control means for prohibiting pulse supercharging using the pulse supercharging on-off valve when the high pressure EGR gas is recirculated using the high pressure EGR passage;
A control device for an internal combustion engine, comprising:

  Depending on the combustion state of the internal combustion engine, the combustion stability may not be maintained unless high-pressure EGR gas is introduced into the cylinder. In this case, the EGR operation using the high pressure EGR passage must be performed with priority.

  Here, when the internal combustion engine is provided with a high pressure EGR passage, the high pressure EGR gas supply port connected to the intake passage is downstream of the compressor and is arranged in the vicinity of the pulse supercharging on / off valve. Is done. In this case, if pulse supercharging is performed while performing EGR operation using the high pressure EGR passage, the high pressure EGR gas excessively flows into the internal combustion engine from the high pressure EGR passage due to the pulse supercharging. Then, the EGR rate of the intake air introduced into the cylinder changes, and the combustion state of the internal combustion engine is deteriorated.

  Therefore, in the present invention, when the high pressure EGR gas is recirculated using the high pressure EGR passage, the pulse supercharging using the pulse supercharging on / off valve is prohibited.

  According to this, since the pulse supercharging is not performed while the high pressure EGR gas is recirculated using the high pressure EGR passage, the high pressure EGR gas may excessively flow into the internal combustion engine from the high pressure EGR passage. Absent.

  Therefore, when EGR operation using the high pressure EGR passage is performed with priority, pulse supercharging is not performed, so that the EGR rate of the intake air introduced into the internal combustion engine is stabilized, and the combustion state of the internal combustion engine is reduced. Can keep good.

  According to the present invention, in the control device for an internal combustion engine, the EGR rate of the intake air introduced into the cylinder is stabilized, and the combustion state of the internal combustion engine can be kept good.

  Specific examples of the present invention will be described below.

<Example 1>
FIG. 1 is a diagram showing a schematic configuration of an internal combustion engine to which the control device for an internal combustion engine according to the present embodiment is applied.

  The internal combustion engine 1 shown in FIG. 1 is a diesel engine. The internal combustion engine 1 includes a fuel injection valve 3 that can inject fuel directly into each cylinder 2 and an intake passage 4 that guides air into each cylinder 2. A compressor unit 50 and an intercooler 6 of a centrifugal supercharger (turbocharger) 5 are disposed in the intake passage 4.

  The intake air supercharged by the compressor unit 50 is cooled by the intercooler 6 and then guided into each cylinder 2. The intake air introduced into each cylinder 2 is ignited and burned in the cylinder 2 together with the fuel injected from the fuel injection valve 3.

  The gas burned in each cylinder 2 is discharged to the exhaust passage 7. The exhaust discharged into the exhaust passage 7 is released into the atmosphere via the turbine section 51 and the exhaust purification device 8 arranged in the middle of the exhaust passage 7.

  As the exhaust purification device 8, a NOx storage reduction catalyst having oxidation ability and NOx storage capacity, a particulate filter having oxidation ability and PM trapping capacity, a particulate filter carrying a storage reduction type NOx catalyst, or the like is used. It can be illustrated.

  The intake passage 4 and the exhaust passage 7 described above are connected to each other by a low pressure EGR passage 9. Specifically, the exhaust passage 7 downstream from the exhaust purification device 8 and the intake passage 4 upstream from the compressor unit 50 are connected to each other by a low-pressure EGR passage 9.

  In the middle of the low pressure EGR passage 9, there are a low pressure EGR valve 10 that adjusts the cross-sectional area of the low pressure EGR passage 9, and a low pressure EGR cooler 11 that cools the gas (low pressure EGR gas) flowing through the low pressure EGR passage 9. Has been placed. The amount of low pressure EGR gas flowing through the low pressure EGR passage 9 is adjusted by the opening degree of the low pressure EGR valve 10.

  The intake passage 4 and the exhaust passage 7 described above are connected to each other by a high pressure EGR passage 12. Specifically, the exhaust passage 7 upstream from the turbine section 51 and the intake passage 4 downstream from the intercooler 6 are connected to each other by a high-pressure EGR passage 12.

  In the middle of the high-pressure EGR passage 12, a high-pressure EGR valve 13 that adjusts the cross-sectional area of the high-pressure EGR passage 12 and a high-pressure EGR cooler 14 that cools the gas (high-pressure EGR gas) that flows through the high-pressure EGR passage 12 are provided. Has been placed. The amount of EGR gas flowing through the high pressure EGR passage 12 is adjusted by the opening degree of the high pressure EGR valve 13.

  The intake passage 4 downstream from the connecting portion of the high-pressure EGR passage 12 is branched into the same number (four in this case) of branch pipes 40 as the number of cylinders of the internal combustion engine 1. Each branch pipe 40 communicates with the cylinder 2 of the internal combustion engine 1 (hereinafter, the four branch pipes are collectively referred to as “intake manifolds”).

  Each branch pipe of the intake manifold 40 is provided with a pulse supercharging on / off valve 15 that opens and closes the passage of each branch pipe.

  The fuel injection valve 3, the low pressure EGR valve 10, the high pressure EGR valve 13, and the pulse supercharging on / off valve 15 are electrically controlled by the ECU 16. The ECU 16 is attached to the internal combustion engine 1, a measured value of an air flow meter 17 disposed in the intake passage 4, a measured value of an air-fuel ratio sensor (A / F sensor) 18 disposed in the exhaust passage 7 downstream of the exhaust purification device 8. The fuel injection valve 3, the low pressure EGR valve 10, the high pressure EGR valve 13, and the pulse supercharging on / off valve 15 are controlled using the measured value of the crank position sensor 19 and the measured value of the accelerator position sensor 20 as parameters.

  For example, when the low pressure EGR valve 10 is opened, the low pressure EGR passage 9 becomes conductive, and a part of the exhaust gas flowing out from the exhaust gas purification device 8 becomes low pressure EGR gas via the low pressure EGR passage 9 to the intake passage 4. Inflow. The low-pressure EGR gas that has flowed into the intake passage 4 is recirculated to the internal combustion engine 1 via the compressor unit 50 and the intake manifold 40.

  When the high pressure EGR valve 13 is opened, the high pressure EGR passage 12 becomes conductive, and a part of the exhaust gas flowing through the exhaust passage 7 flows into the intake manifold 40 via the high pressure EGR passage 12 as high pressure EGR gas. Then, it is recirculated to the internal combustion engine 1.

  Thus, an EGR operation in which a part of the exhaust gas is recirculated to the internal combustion engine 1 as EGR gas (low pressure EGR gas and high pressure EGR gas are collectively referred to as EGR gas) via the low pressure EGR passage 9 and / or the high pressure EGR passage 12. As a result, the combustion temperature of the internal combustion engine 1 can be lowered, and the amount of NOx emissions generated in the combustion process can be reduced.

  Here, the conditions of the operating state of the internal combustion engine 1 that can suitably execute the EGR operation using the low-pressure EGR passage 9 and the EGR operation using the high-pressure EGR passage 12 are obtained in advance by experiments or the like. In this embodiment, the exhaust gas recirculation is performed by switching the EGR operation using the low pressure EGR passage 9 and the high pressure EGR passage 12 according to the operation state of the internal combustion engine 1 or in combination.

  FIG. 2 is a diagram showing an EGR operation switching pattern determined for each operating state region of the internal combustion engine 1. 2 represents the engine speed of the internal combustion engine 1, and the vertical axis represents the engine load of the internal combustion engine 1.

  In FIG. 2, a region HPL is a region where the operating state of the internal combustion engine 1 is low load and low rotation, and here, EGR operation using the high pressure EGR passage 12 is performed. The region LPL + HPL is a region where the operation state of the internal combustion engine 1 is a medium load and medium speed rotation, and here, EGR operation using the high pressure EGR passage 12 and the low pressure EGR passage 9 is used together. The region LPL is a region where the operating state of the internal combustion engine 1 is a high load and high rotation, and here, EGR operation using the low pressure EGR passage 9 is performed.

  As described above, the EGR operation can be performed in a wide range of operation by switching or using the EGR operation using the high pressure EGR passage 12 and the low pressure EGR passage 9 together.

  On the other hand, in order to compensate for the supercharging delay (turbo lag) of the turbocharger 5 when the acceleration operation of the internal combustion engine 1 is started, pulse supercharging is performed using the pulse supercharging on / off valve 15.

  As shown in FIG. 3, the pulse supercharging operation of the pulse supercharging on / off valve 15 is performed before the intake valve is opened (specifically, after the intake valve is closed in the immediately preceding cycle). This is an operation that is opened before the valve starts to close.

  According to such pulse supercharging, the pulse supercharging on / off valve 15 is provided in the period from the opening start timing of the intake valve to the valve opening start timing of the pulse supercharging on / off valve 15 (first period in FIG. 3). The passage from the valve to the intake valve is negative pressure. When the pulse supercharging on / off valve 15 is opened, the gas upstream of the pulse supercharging on / off valve 15 is rapidly transferred to the cylinder 2 by the negative pressure in the passage from the pulse supercharging on / off valve 15 to the intake valve. It begins to flow in. As a result, the inertial supercharging effect of the intake air is increased and the gas charging efficiency in the cylinder 2 is improved.

  By the way, the supply port of the high pressure EGR gas to which the high pressure EGR passage 12 is connected to the intake passage 4 is arranged downstream of the compressor unit 50 and immediately upstream of the pulse supercharging on / off valve 15. In this case, if pulse supercharging is performed while performing EGR operation using the high pressure EGR passage 12, the high pressure EGR gas excessively flows into the internal combustion engine 1 from the high pressure EGR passage 12 due to the pulse supercharging. Then, the ratio of EGR gas to the intake air introduced into the cylinder 2 (EGR rate) changes, and the combustion state of the internal combustion engine 1 is deteriorated.

  Therefore, in this embodiment, when the pulse supercharging is performed using the pulse supercharging on / off valve 15, the high pressure EGR gas 12 is prohibited from being refluxed using the high pressure EGR passage 12.

  According to this, since the high pressure EGR gas is not recirculated during the pulse supercharging, the high pressure EGR gas does not flow into the internal combustion engine 1 from the high pressure EGR passage 12.

  On the other hand, it is necessary to supply EGR gas to the internal combustion engine 1 according to the operating state of the internal combustion engine 1. Here, in the low pressure EGR passage 9, the supply port of the low pressure EGR gas connected to the intake passage 4 is upstream of the compressor unit 50. For this reason, it is not affected by pulse supercharging. Therefore, the amount of EGR gas to be introduced into the cylinder 2 can be stably supplied by the EGR operation using the low pressure EGR passage 9. That is, the amount of EGR gas required by the internal combustion engine 1 is supplied by recirculating the low pressure EGR gas using the low pressure EGR passage 9.

  Accordingly, the pulse supercharging and the EGR operation using the low pressure EGR passage 9 are performed simultaneously, the EGR rate of the intake air introduced into the internal combustion engine 1 is stabilized, and the combustion state of the internal combustion engine 1 can be kept good.

  Here, a control routine when the internal combustion engine 1 of the present embodiment performs pulse supercharging will be described based on the flowchart shown in FIG. This routine is stored in advance in the ECU 16 and is a routine that is periodically executed.

  In step S101, first, the ECU 16 determines whether or not the operating state of the internal combustion engine 1 is in the pulse supercharging execution region. For example, the pulse supercharging execution region is determined when there is a possibility that a turbocharging delay of the turbocharger 5 may occur at the start of the acceleration operation of the internal combustion engine 1 where the value of the accelerator position sensor 20 read by the ECU 16 becomes large.

  If an affirmative determination is made in step S101, the process proceeds to step S102. On the other hand, if a negative determination is made, this control routine is temporarily terminated.

  In step S102, the ECU 16 fully closes the high pressure EGR valve 13 and controls the low pressure EGR valve 10 to open.

  By fully closing the high pressure EGR valve 13, the EGR operation using the high pressure EGR passage 12 is prohibited.

  Further, by controlling the low pressure EGR valve 10 to open, only the EGR operation using the low pressure EGR passage 9 supplies the EGR gas amount required by the internal combustion engine depending on the operating state. Thereby, the EGR rate of the intake air introduced into the cylinder 2 is stabilized. For this reason, the opening degree of the low-pressure EGR valve 10 is controlled to an opening degree that compensates for the amount of EGR gas that decreases when the high-pressure EGR valve 13 is fully closed.

  In step S103, the ECU 16 performs pulse supercharging. Specifically, the pulse supercharging on / off valve 15 is pulse-supercharged according to the timing shown in FIG. Thereafter, this control routine is temporarily terminated.

  The ECU 16 that executes this control routine corresponds to the first control means of the present invention. Therefore, by executing the control routine, the pulse supercharging and the EGR operation using the low pressure EGR passage are simultaneously performed. Thereby, the EGR rate of the intake air introduced into the internal combustion engine is stabilized, and the combustion state of the internal combustion engine can be kept good.

<Example 2>
In the present embodiment, a case where priority is given to EGR operation using the high-pressure EGR passage 12 will be described. The description of the items described in the above embodiment is omitted, and only the characteristic part of this embodiment is described.

  Depending on the combustion state of the internal combustion engine 1, combustion stability may not be maintained unless high pressure EGR gas is introduced into the cylinder 2. In this case, the EGR operation using the high-pressure EGR passage 12 must be performed with priority.

  However, when the internal combustion engine 1 includes the high-pressure EGR passage 12, the high-pressure EGR gas supply port to which the high-pressure EGR passage 12 is connected to the intake passage 4 is downstream of the compressor, and the pulse supercharging on-off valve 15 is arranged in the vicinity. In this case, if pulse supercharging is performed while performing EGR operation using the high pressure EGR passage 12, the high pressure EGR gas excessively flows into the internal combustion engine 1 from the high pressure EGR passage 12 due to the pulse supercharging. Then, the EGR rate of the intake air introduced into the cylinder 2 changes, and the combustion state of the internal combustion engine 1 is deteriorated.

  Therefore, in the present embodiment, the high pressure EGR passage 12 is used to recirculate the high pressure EGR gas, that is, when the EGR operation using the high pressure EGR passage 12 is performed, the pulse supercharging valve 15 is used for pulse supercharging. It was banned.

  According to this, since the pulse supercharging is not performed during the EGR operation using the high pressure EGR passage 12, the high pressure EGR gas does not excessively flow into the internal combustion engine 1 from the high pressure EGR passage 12 due to the pulse supercharging. .

  Therefore, when the EGR operation using the high-pressure EGR passage 12 is performed with priority, the pulse supercharging is not performed, so that the EGR rate of the intake air introduced into the internal combustion engine 1 is stabilized, and the internal combustion engine 1 The combustion state can be kept good.

  Here, the control routine when the internal combustion engine 1 of the present embodiment performs pulse supercharging will be described based on the flowchart shown in FIG. This routine is stored in advance in the ECU 16 and is a routine that is periodically executed.

  In step S201, first, the ECU 16 determines whether or not the operating state of the internal combustion engine 1 is in the pulse supercharging execution region. For example, the pulse supercharging execution region is determined when there is a possibility that a turbocharging delay of the turbocharger 5 may occur at the start of the acceleration operation of the internal combustion engine 1 where the value of the accelerator position sensor 20 read by the ECU 16 becomes large.

  If an affirmative determination is made in step S201, the process proceeds to step S202. On the other hand, if a negative determination is made, this control routine is temporarily terminated.

  In step S202, the ECU 16 determines whether or not the EGR operation (HPL) using the high pressure EGR passage 12 is prioritized. Specifically, if the combustion state of the internal combustion engine 1 cannot maintain the combustion stability unless high-pressure EGR gas is introduced into the cylinder 2, it is determined that EGR operation using the high-pressure EGR passage 12 is prioritized. Is done.

  If an affirmative determination is made in step S202, the process proceeds to step S203, whereas if a negative determination is made, the process proceeds to step S204.

  In step S203, the ECU 16 prohibits pulse supercharging. At that time, the EGR operation using the high-pressure EGR passage 12 currently being carried out is continued. That is, the opening degree of the high pressure EGR valve 13 is maintained. Thereafter, this control routine is temporarily terminated.

  On the other hand, in step S204, the ECU 16 fully closes the high pressure EGR valve 13 and controls the low pressure EGR valve 10 to open.

  By fully closing the high pressure EGR valve 13, the EGR operation using the high pressure EGR passage 12 is prohibited.

  Further, by controlling the low pressure EGR valve 10 to open, only the EGR operation using the low pressure EGR passage 9 supplies the EGR gas amount required by the internal combustion engine depending on the operating state. Thereby, the EGR rate of the intake air introduced into the cylinder 2 is stabilized. For this reason, the opening degree of the low-pressure EGR valve 10 is controlled to an opening degree that compensates for the amount of EGR gas that decreases when the high-pressure EGR valve 13 is fully closed.

  In step S205, the ECU 16 performs pulse supercharging. Specifically, the pulse supercharging on / off valve 15 is pulse-supercharged according to the timing shown in FIG. Thereafter, this control routine is temporarily terminated.

  The ECU that executes this control routine corresponds to the second control means of the present invention. Therefore, when the EGR operation using the high pressure EGR passage is performed with priority by executing the control routine, pulse supercharging is not performed. Thereby, the EGR rate of the intake air introduced into the internal combustion engine is stabilized, and the combustion state of the internal combustion engine can be kept good.

  The control device for an internal combustion engine according to the present invention is not limited to the above-described embodiments, and various modifications may be made without departing from the gist of the present invention.

1 is a diagram illustrating an internal combustion engine and an intake / exhaust system thereof according to Embodiment 1. FIG. It is a figure which shows the map for switching the EGR driving which concerns on Example 1. FIG. It is a figure which shows the pulse supercharging operation | movement of the on-off valve for pulse supercharging which concerns on Example 1. FIG. 3 is a flowchart illustrating a control routine when the internal combustion engine according to the first embodiment performs pulse supercharging. 7 is a flowchart illustrating a control routine when the internal combustion engine according to the second embodiment performs pulse supercharging.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Internal combustion engine 2 Cylinder 3 Fuel injection valve 4 Intake passage 5 Turbocharger 6 Intercooler 7 Exhaust passage 8 Exhaust purification device 9 Low pressure EGR passage 10 Low pressure EGR valve 11 Low pressure EGR cooler 12 High pressure EGR passage 13 High pressure EGR valve 14 High pressure EGR cooler 15 On / off valve 16 ECU for pulse supercharging
17 Air Flow Meter 19 Crank Position Sensor 20 Accelerator Position Sensor 40 Intake Manifold 50 Compressor 51 Turbine

Claims (3)

A turbocharger having a turbine disposed in an exhaust passage of an internal combustion engine and a compressor disposed in an intake passage of the internal combustion engine;
A low pressure EGR passage that takes in a part of exhaust gas as low pressure EGR gas from the exhaust passage downstream of the turbine and recirculates the low pressure EGR gas to the intake passage upstream of the compressor;
A high-pressure EGR passage that takes a part of the exhaust as high-pressure EGR gas from the exhaust passage upstream of the turbine and recirculates the high-pressure EGR gas to the intake passage downstream of the compressor;
An on / off valve for pulse supercharging provided in the intake passage downstream of the compressor and upstream of the intake valve of the internal combustion engine;
A first control means for prohibiting recirculation of the high-pressure EGR gas using the high-pressure EGR passage when performing pulse supercharging using the pulse supercharging on-off valve;
A control apparatus for an internal combustion engine, comprising:   The first control means prohibits recirculation of the high-pressure EGR gas using the high-pressure EGR passage when the pulse-supercharging is performed using the pulse supercharging on-off valve, and the internal combustion engine requires 2. The control device for an internal combustion engine according to claim 1, wherein an EGR gas amount is supplied by recirculating the low pressure EGR gas using the low pressure EGR passage. A turbocharger having a turbine disposed in an exhaust passage of an internal combustion engine and a compressor disposed in an intake passage of the internal combustion engine;
A low pressure EGR passage that takes a part of exhaust gas as low pressure EGR gas from the exhaust passage downstream of the turbine and recirculates the low pressure EGR gas to the intake passage upstream of the compressor;
A high-pressure EGR passage that takes a part of the exhaust as high-pressure EGR gas from the exhaust passage upstream of the turbine and recirculates the high-pressure EGR gas to the intake passage downstream of the compressor;
An on / off valve for pulse supercharging provided in the intake passage downstream of the compressor and upstream of the intake valve of the internal combustion engine;
A second control means for prohibiting pulse supercharging using the pulse supercharging on / off valve when the high pressure EGR gas is recirculated using the high pressure EGR passage;
A control apparatus for an internal combustion engine, comprising:

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