JP2015124680A - Control device for internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device for an internal combustion engine equipped with a mechanical supercharger whose discharge amount is changeable, for setting the discharge amount of the supercharger into a wider changeable range while suppressing knocking.SOLUTION: A control device 2 for an internal combustion engine 1 equipped with a mechanical supercharger 13 whose discharge amount is changeable includes a first EGR valve 29 provided in an EGR passage 27 connecting an exhaust passage 7 and an intake passage 6 of the internal combustion engine, and effective compression ratio variable mechanisms 65, 66 for changing an opening/closing timing for an intake valve 61 to change an effective compression ratio. On the basis of a required load required for the internal combustion engine, it controls the supercharger, the first EGR valve and the effective compression ratio variable mechanisms.

Description

  The present invention relates to a control device for an internal combustion engine including a mechanical supercharger capable of changing a discharge amount.

  In some internal combustion engines, a mechanical supercharger, a crankshaft, and an electric motor are connected to each other via a planetary gear mechanism (for example, Patent Document 1). In this internal combustion engine, the rotating shaft of the supercharger is connected to the sun gear of the planetary gear mechanism, the crankshaft is connected to the planetary carrier via a power transmission mechanism such as a belt and a pulley, and the rotating shaft of the electric motor is connected to the internal gear. Is connected. As a result, the supercharger rotates by receiving a driving force from at least one of the crankshaft and the electric motor. In this internal combustion engine, the rotational speed of the supercharger can be changed by changing the rotational speed of the electric motor. Therefore, in response to operating conditions based on the accelerator opening, shift position, etc., the discharge amount of the turbocharger is increased to increase the output at high loads, and the discharge amount of the turbocharger is reduced at low loads. Unnecessary output can be reduced.

Japanese Patent No. 3315549

  However, when the discharge amount of the supercharger is increased at a high load, there is a problem that knocking is likely to occur. Therefore, in order to avoid knocking, there is a problem that the range in which the discharge amount of the supercharger can be changed is limited, and output according to the required load cannot be realized.

  In view of the above background, the present invention broadens the range in which the discharge amount of a supercharger can be changed while suppressing knocking in a control device for an internal combustion engine provided with a mechanical supercharger capable of changing the discharge amount. This is the issue.

  In order to solve the above-mentioned problem, there is provided a control device (2) for an internal combustion engine (1) provided with a mechanical supercharger (13) capable of changing the discharge amount, the exhaust passage (7) of the internal combustion engine. The effective compression ratio is variable by changing the opening / closing timing of the first EGR valve (29) provided in the EGR passage (27) connecting the intake passage (6) and the intake valve (61). And a mechanism (65, 66) for controlling the supercharger, the first EGR valve, and the effective compression ratio variable mechanism based on a required load required for the internal combustion engine. To do.

  According to this configuration, when changing the discharge amount of the supercharger, the EGR rate that is the ratio of the EGR gas amount to the fresh air amount can be changed by controlling the first EGR valve, and the variable compression ratio mechanism Can be controlled to change the effective compression ratio. Therefore, in a situation where the discharge amount from the supercharger increases and knocking is likely to occur, the occurrence of knocking can be suppressed by controlling the first EGR valve and the effective compression ratio variable mechanism.

  In the above invention, in the high load region where the required load is high, the EGR rate, which is the ratio of the EGR gas amount to the fresh air amount, is increased with respect to the increase in the required load, and the discharge amount of the supercharger is increased. Increase it.

  According to this configuration, since the occurrence of knocking is suppressed by the increase in the EGR rate, knocking hardly occurs even when the discharge amount of the supercharger is increased. That is, it is possible to widen the changeable range of the discharge amount of the supercharger while suppressing the occurrence of knocking.

  In the above invention, in a high load region where the required load is high, the effective compression ratio may be decreased and the discharge amount of the supercharger may be increased as the required load increases.

  According to this configuration, since the occurrence of knocking is suppressed due to a decrease in the effective compression ratio, knocking is less likely to occur even if the discharge amount of the supercharger is increased. That is, it is possible to widen the changeable range of the discharge amount of the supercharger while suppressing the occurrence of knocking.

  In the above invention, the EGR passage branches from the first EGR passage, the first EGR passage (27) connecting the exhaust passage and an upstream portion of the intake passage from the supercharger, The intake passage includes a second EGR passage (31) connected to a portion downstream of the supercharger in the intake passage, and a second EGR valve (32) provided in the second EGR passage, wherein the first EGR valve is the first EGR valve. The EGR passage is provided closer to the exhaust passage than the portion where the second EGR passage branches, and the turbocharger is prohibited from rotating in the low load region where the required load is low, and the second EGR passage is opened. In a high load region where the pressure is high, it is preferable that the rotation of the supercharger is permitted and the second EGR passage is closed.

  According to this configuration, EGR gas is supplied to the intake passage without flowing back through the EGR passage when the turbocharger is stopped and driven.

  In the above invention, in the high load region, correction may be performed so that the discharge amount of the supercharger increases as the EGR rate increases.

  According to this configuration, when the amount of fresh air passing through the supercharger decreases when the EGR gas passes through the supercharger in the high load region, the discharge amount of the supercharger is reduced according to the increase in the EGR rate. By increasing, it is possible to suppress a decrease in the amount of fresh air and maintain an appropriate amount of fresh air.

  In the above invention, the supercharger is connected to the crankshaft (37) and the electric motor (36) of the internal combustion engine via a planetary gear mechanism (35), and the planetary gear mechanism is connected to the supercharger. The sun gear (44) connected to the rotating shaft (13A) of the machine, the internal gear (45) connected to the electric motor, and the planetary gear (46) meshing with the sun gear and the internal gear are rotatable. A planet carrier (47) supported and connected to the crankshaft may be provided.

  According to this configuration, since the supercharger is connected to the crankshaft and the electric motor via the planetary gear mechanism that is a differential gear mechanism, power transmission is performed between at least one of the crankshaft and the electric motor. It becomes possible. Thus, the supercharger is driven by receiving a driving force from at least one of the crankshaft and the electric motor, and transmits the driving force to at least one of the crankshaft and the electric motor to generate power by the electric motor and Assist can be performed. In addition, driving force can be exchanged between the crankshaft and the electric motor.

  According to the above configuration, in the control device for an internal combustion engine provided with a mechanical supercharger capable of changing the discharge amount, it is possible to widen the changeable range of the discharge amount of the supercharger while suppressing knocking. .

1 is a configuration diagram of an internal combustion engine according to a first embodiment. Schematic diagram showing the engine body The flowchart which shows the control procedure by ECU which concerns on 1st Embodiment. The flowchart which shows the control procedure of the discharge amount (SC discharge amount) of the supercharger by ECU which concerns on 1st Embodiment. A map that defines the relationship between engine speed, accelerator opening, and required torque A map that defines the relationship between engine speed, required torque, and operating range (A) Map defining the relationship between required torque and target fresh air amount according to the first embodiment, (B) Map defining the relationship between required torque and target EGR rate (C) Required torque and target effective compression ratio (D) Map that defines the relationship between required torque and target SC discharge amount A map that defines the relationship between the required torque and the opening of the second EGR valve A map that defines the relationship between the target fresh air volume, first intake pressure, engine speed, and target throttle opening (A) A map that defines the relationship between the target EGR rate, the second intake pressure, and the first EGR valve opening degree in the region A. (A) In the region B, the target EGR rate, the first intake pressure, and the first EGR valve opening. A map that defines the degree relationship Map specifying target SC speed, target SC outlet pressure, and SC volumetric efficiency estimate Map that defines the relationship between engine speed, required torque, and operation area according to the second embodiment (A) Map defining the relationship between required torque and target fresh air amount according to the second embodiment, (B) Map defining the relationship between required torque and target EGR rate (C) Required torque and target effective compression ratio (D) Map that defines the relationship between required torque and target SC discharge amount

(First embodiment)
Hereinafter, a first embodiment in which the present invention is applied to an internal combustion engine of an automobile will be described with reference to the drawings. The internal combustion engine according to the first embodiment includes an internal combustion engine 1 mounted on a vehicle as a driving power source, and an ECU 2 (electronic control unit) that controls the operation of the internal combustion engine 1. The internal combustion engine 1 is a 4-stroke internal combustion engine.

  The internal combustion engine 1 has a plurality of cylinders 4 and a combustion chamber 5 formed corresponding to the cylinders 4 in the engine body 3, an intake passage 6 for supplying air to the combustion chamber 5, and exhaust gas from the combustion chamber 5. And an exhaust passage 7 for discharging the gas. In the intake passage 6, an intake inlet 11, an air cleaner (not shown), a throttle valve 12, a supercharger 13, an intercooler 14, an intake manifold 15, and an intake port 16 are provided in series in the order described from the upstream side. In the exhaust passage 7, an exhaust port 21, an exhaust manifold 22, a catalytic converter 23, a silencer (not shown), and an exhaust outlet 24 are provided in series in the order described from the upstream side.

  An EGR device 26 is provided between the intake passage 6 and the exhaust passage 7 of the internal combustion engine 1. The EGR device 26 is a device that recirculates part of the exhaust gas to the intake side and supplies the recirculated exhaust gas together with air to the combustion chamber 5 of each cylinder 4. The EGR device 26 has a first EGR passage 27 that connects the exhaust passage 7 and a portion of the intake passage 6 upstream of the supercharger 13. Specifically, the first EGR passage 27 is connected to a portion of the exhaust passage 7 downstream of the catalytic converter 23 and a portion of the intake passage 6 between the throttle valve 12 and the supercharger 13.

  The first EGR passage 27 is provided with an EGR cooler 28 as exhaust gas cooling means for cooling the gas passing through the passage, and a first EGR valve 29 for opening and closing the passage in order from the exhaust passage 7 side. By controlling the opening degree of the first EGR valve 29, it is possible to control the EGR rate (the ratio of the amount of EGR gas (exhaust gas) to the amount of fresh air supplied to the combustion chamber 5).

  The EGR device 26 also has a second EGR passage 31 that connects a portion of the first EGR passage 27 closer to the intake passage 6 than the first EGR valve 29 and a portion of the intake passage 6 downstream of the supercharger 13. ing. Specifically, the second EGR passage 31 is connected to a portion of the intake passage 6 between the supercharger 13 and the intercooler 14. The second EGR passage 31 is provided with a second EGR valve 32 that opens and closes the passage.

  The first EGR passage 27 and the second EGR passage 31 also function as a bypass passage that bypasses the supercharger 13 and the intercooler 14 in the intake passage 6. The second EGR valve 32 functions as a bypass valve that opens and closes the bypass passage.

  When the first EGR valve 29 is closed, the EGR gas (exhaust gas) is not recirculated from the exhaust passage 7 to the intake passage 6. When the first EGR valve 29 is opened and the second EGR valve 32 is closed, EGR gas passes through the first EGR passage 27 and is supplied to the intake passage 6 from a portion between the throttle valve 12 and the supercharger 13. The In the state where the first EGR valve 29 and the second EGR valve 32 are opened, the exhaust passes through the first EGR passage 27 and the second EGR passage 31, and the portion between the throttle valve 12 and the supercharger 13 and the intercooler 14 The air is supplied to the intake passage 6 from a portion between the intake manifold 15 and the intake manifold 15. The distribution ratio of the EGR gas to the upstream side and the downstream side of the supercharger 13 in the intake passage 6 includes the opening degree of the second EGR valve 32, the pressure difference between the upstream side and the downstream side of the supercharger 13 in the intake passage 6 and the like. It depends on.

  The throttle valve 12 is an electric throttle valve 12, and its opening degree is controlled by an electric motor (not shown).

  The supercharger 13 is a mechanical supercharger (supercharger) 13. The supercharger 13 may be a known mechanical supercharger such as a roots type, a resholm type, or a scroll type. The rotating shaft 13 </ b> A of the supercharger 13 is connected to an electric motor 36 and a crankshaft 37 that is a driving shaft of the engine body 3 through a planetary gear mechanism 35.

  The rotating shaft 13 </ b> A of the supercharger 13 is connected to the casing 42 of the supercharger 13 via the first clutch 41. The casing 42 is fixed so as not to be displaced with respect to the vehicle body. The first clutch 41 is controlled by the ECU 2 and connects the rotating shaft 13A of the supercharger 13 and the casing 42 in the connected state to regulate the rotation of the rotating shaft 13A of the supercharger 13, and the supercharger in the disconnected state. The rotation shaft 13A of the supercharger 13 is allowed to rotate by cutting the 13 rotation shaft 13A and the casing 42. The first clutch 41 is preferably a normally closed type that maintains the connection during normal times. For example, the first clutch 41 is a clutch driven by electric power, and may be disconnected when receiving supply of electric power.

  The planetary gear mechanism 35 includes a sun gear 44 having external teeth, an internal gear (ring gear) 45 arranged coaxially with the sun gear (sun gear) 44, and a plurality of planetary gears meshing with both the sun gear 44 and the internal gear 45. (Planetary gear) 46, and each planetary gear 46 is rotatably supported and has a planetary carrier (planetary carrier) 47 arranged coaxially with the sun gear 44. The sun gear 44 is connected to the rotating shaft 13A of the supercharger 13 and rotates integrally. External teeth 45 </ b> A are formed on the outer peripheral portion of the internal gear 45, and the external teeth 45 </ b> A mesh with a gear 36 </ b> B provided on the rotation shaft 36 </ b> A of the electric motor 36. Thereby, the electric motor 36 and the internal gear 45 rotate in synchronization. The planet carrier 47 is connected to the crankshaft 37 through the power transmission mechanism 50.

When the gear ratio of the planetary gear mechanism 35 and the planetary gear mechanism gear ratio [rho _1, the planetary gear mechanism gear ratio [rho ₁ is represented by Zr / Zs. Here, Zr is the number of teeth of the internal gear 45, and Zs is the number of teeth of the sun gear 44.

  The power transmission mechanism 50 is provided between the first pulley 51, the second pulley 52, the belt 53 spanned between the first pulley 51 and the second pulley 52, and the first pulley 51 and the crankshaft 37. And a second clutch 54. The second pulley 52 is coaxially coupled to the planet carrier 47 and rotates integrally. Connection and disconnection of the second clutch 54 are controlled by the ECU 2.

The power transmission mechanism speed ratio ρ ₂ that is the speed ratio of the power transmission mechanism 50 is a value obtained by dividing the diameter of the first pulley 51 by the diameter of the second pulley 52. In a state where the second clutch 54 is connected, a second pulley 52 is rotated at a rotational speed value multiplied by the power transmission mechanism gear ratio [rho ₂ to the rotational speed of the crankshaft 37.

When the internal gear 45 is fixed and the engine speed (the speed of the crankshaft 37) is N _E , the speed N _SC of the rotary shaft 13A of the supercharger 13 is N _SC = (1 + ρ ₁ ) × ρ ₂ × N _E

  The supercharger 13 can take a stop mode in which the rotation shaft 13A of the supercharger 13 does not rotate and first to third drive modes in which the rotation shaft 13A of the supercharger 13 rotates. In the stop mode, the first clutch 41 is connected (ON), and the rotation of the rotary shaft 13A of the supercharger 13 and the sun gear 44 is prohibited. In the stop mode, the crankshaft 37 and the electric motor 36 rotate synchronously with a predetermined speed ratio. Thereby, the electric motor 36 can generate electric power by receiving the driving force of the crankshaft 37. Further, the driving force of the electric motor 36 is transmitted to the crankshaft 37, and the driving of the crankshaft 37 can be assisted. For example, when the internal combustion engine 1 is started, the driving force of the electric motor 36 can be transmitted to the crankshaft 37 to perform cranking.

  In each drive mode, the first clutch 41 is disconnected (OFF), and the rotation of the rotating shaft 13A of the supercharger 13 and the sun gear 44 is allowed. In the first drive mode, the internal gear 45 is fixed, and the rotating shaft 13A of the supercharger 13 rotates with a predetermined speed ratio with respect to the crankshaft 37. In the second drive mode, the driving force of the electric motor 36 and the crankshaft 37 is transmitted to the supercharger 13 via the planetary gear mechanism 35. In this state, the rotational speed of the supercharger 13 can be increased or decreased by controlling the rotational speed of the electric motor 36, and the rotational speed of the supercharger 13 is changed with respect to the rotational speed of the crankshaft 37. Can do. In the third drive mode, the planet carrier 47 is fixed, and the rotating shaft 13A of the supercharger 13 rotates at a predetermined speed ratio with respect to the electric motor 36.

  The supercharger 13 changes the amount of air to be discharged (hereinafter referred to as SC discharge amount) as the rotational speed of the rotating shaft 13A changes.

  The engine body 3 includes an intake valve 61 for opening and closing the intake port 16, an exhaust valve 62 for opening and closing the exhaust port 21, an intake valve driving mechanism 63 for opening and closing the intake valve 61, and an exhaust valve 62. An exhaust valve drive mechanism 64 that opens and closes is provided.

  The intake valve drive mechanism 63 variably controls the effective compression ratio of the combustion chamber 5 of each cylinder 4 and opens the intake valve 61 in order to realize the operation of the internal combustion engine 1 in the Atkinson cycle (Miller cycle). A known valve phase variable mechanism 65 (VTC) for changing the phase angle of the period, and a known value for changing the lift amount (maximum opening) of the intake valve 61 of the intake valve 61 and the angular width of the valve opening period. The variable valve lift mechanism 66 (VTEC). The angle width of the valve opening period of the intake valve 61 represents the valve opening period from the start to the end of opening of the intake valve 61 by the rotation angle of the crankshaft 37 that is the output shaft of the internal combustion engine 1. .

  As shown in FIG. 2, the variable valve lift mechanism 66 of the intake valve drive mechanism 63 includes two intake cams 69 </ b> A and 69 </ b> B for each cylinder 4. Each intake cam 69A, 69B is coupled to the intake camshaft 70 so as to rotate integrally with the intake camshaft 70. The profiles of the intake cams 69A and 69B are set such that the lift amount (maximum opening) of the intake valve 61 and the angular width of the valve opening period are different from each other. The profiles of the intake cams 69A and 69B differ from each other in the lift amount and the angular width of the valve opening period.

  The angle width of the valve opening period of the intake valve 61 by the large lift intake cam 69A is set to an angle width that is wider than the angle width of the valve opening period of the intake valve 61 by the small lift intake cam 69B and close to 180 °. The angular width of the valve opening period of the intake valve 61 by the small lift intake cam 69B is set smaller than 180 °, for example, about 100 °. The small lift intake cam 69B is used as an intake cam for low load operation of the internal combustion engine 1, and the large lift intake cam 69A is used as an intake cam for high load operation of the internal combustion engine 1.

  The variable valve lift mechanism 66 of the intake valve drive mechanism 63 selects an intake cam that opens and closes the intake valve 61 via the rocker arm 71 using hydraulic pressure between the small lift intake cam 69B and the large lift intake cam 69A. To do. Details of such a variable valve lift mechanism 66 are publicly known. For example, refer to Japanese Patent Application Laid-Open No. 2005-180306.

  The variable valve phase mechanism 65 of the intake valve drive mechanism 63 is provided between the intake side camshaft 70 and the crankshaft 37 and changes the phase of the intake side camshaft 70 with respect to the crankshaft 37. More specifically, the variable valve phase mechanism 65 is provided at the end of the intake camshaft 70 and is connected to a crank sprocket (not shown) provided on the crankshaft 37 by a timing chain (not shown). . The variable valve phase mechanism 65 is rotatably supported with respect to the first member (not shown) provided at the end of the intake camshaft 70 and the first member, and an oil chamber is provided between the first member and the valve phase varying mechanism 65. And a second member (not shown) to be formed. A sprocket (not shown) is formed on the outer peripheral portion of the second member. The sprocket of the second member is connected to a crank sprocket provided on the crankshaft 37 by a timing chain.

  The valve phase varying mechanism 65 changes the relative angle between the first member and the second member by supplying hydraulic oil to the oil chamber, and changes the phase of the intake camshaft 70 with respect to the crankshaft 37. By the valve phase varying mechanism 65, each of the small lift intake cam 69B and the large lift intake cam 69A continuously changes the phase angle of the valve opening period within a predetermined range.

  Details of such a valve phase variable mechanism 65 are publicly known. For example, refer to the above-mentioned JP-A-2005-180306. The valve phase varying mechanism 65 has other configurations as long as it can continuously change the phase angle of the small lift intake cam 69B and the large lift intake cam 69A with respect to the phase angle of the crankshaft 37 within a predetermined range. May be adopted.

  As described above, the intake valve drive mechanism 63 includes the variable valve phase mechanism 65 and the variable valve lift mechanism 66, so that the effective compression ratio of the combustion chamber 5 of each cylinder 4 can be variably set. Yes. That is, the variable valve phase mechanism 65 and the variable valve lift mechanism 66 constitute an effective compression ratio variable mechanism.

  When the intake valve 61 is driven to open and close by the small lift intake cam 69B, the phase angle of the valve opening period is set so that the phase angle at the start of closing of the intake valve 61 becomes a phase angle on the advance side with respect to the phase angle at the bottom dead center. Is set, the operation of the internal combustion engine 1 in the Atkinson cycle (Miller cycle) in which the effective compression ratio becomes smaller than the expansion ratio is realized.

  When the intake valve 61 is driven to open and close by the large lift intake cam 69A, the phase angle of the valve opening period is set so that the phase angle of the start of closing of the intake valve 61 is a phase angle that is retarded from the phase angle of the bottom dead center. Is set, the operation of the internal combustion engine 1 in the Atkinson cycle (Miller cycle) in which the effective compression ratio becomes smaller than the expansion ratio is realized. An internal combustion engine in an Otto cycle in which the effective compression ratio is substantially the same as the expansion ratio when the opening and closing of the intake valve 61 are performed at substantially the same phase angle as the top dead center and the bottom dead center, respectively. 1 driving | operation will be implement | achieved.

  Furthermore, the effective compression ratio can be increased or decreased by switching the intake cams 69A and 69B that open and close the intake valve 61 from one of the small lift intake cam 69B and the large lift intake cam 69A. In this case, the effective compression ratio can be increased more when the large lift intake cam 69A is used than when the small lift intake cam 69B is used.

  The exhaust valve 62 is driven by an exhaust valve drive mechanism 64 provided in the engine body 3. The exhaust valve drive mechanism 64 rotates in conjunction with the crankshaft 37 of the internal combustion engine 1 (one rotation for every two rotations of the crankshaft 37), and is connected to the exhaust side corresponding to each exhaust valve 62. And an exhaust cam 73 provided on the camshaft 72. The profile of the exhaust cam 73 is set to a pattern similar to the profile of the large lift intake cam 69A (pattern indicated by the solid line c in FIG. 3), for example, and the angular width of the exhaust valve 62 during the valve opening period is The angle width is set slightly larger than the angle difference (180 deg) between the bottom dead center phase angle and the top dead center phase angle.

  The engine body 3 is provided with a fuel injection device 74 that injects fuel into each combustion chamber 5. In another embodiment, the fuel injection device 74 may inject fuel into the intake passage 6 such as the intake port 16. Further, in the combustion chamber 5 of each cylinder 4 of the engine body 3, an ignition plug 75 for igniting the compressed air-fuel mixture is provided.

  The above is the mechanical configuration of the internal combustion engine 1 (the engine main body 3 and auxiliary equipment attached thereto) of the present embodiment.

  The ECU 2 is an electronic circuit unit including a CPU, a RAM, a ROM, and the like. The ECU 2 includes a throttle valve 12, a valve phase variable mechanism 65 of the intake valve drive mechanism 63, a valve lift variable mechanism 66 (effective compression ratio variable mechanism), and an EGR device 26. The operation of the first EGR valve 29 and the second EGR valve 32, the first clutch 41 of the supercharger 13, the second clutch 54 of the power transmission mechanism 50, the electric motor 36, the fuel injection device 74, and the spark plug 75 is controlled.

  The ECU 2 receives detection signals from various sensors. In the system of this embodiment, a crank angle sensor 81, an accelerator sensor (not shown), an air flow rate sensor 83, a first intake pressure sensor 84, a second intake pressure sensor 85, an exhaust pressure sensor 86, and the like as described below. The detection signals of these sensors are input to the ECU 2.

  The crank angle sensor 81 is provided in the engine body 3 adjacent to the crankshaft 37 and detects a rotation speed (rotational speed) of the crankshaft 37 (specifically, for each predetermined rotation angle of the crankshaft 37). The generated pulse signal is output. The accelerator sensor is provided on an accelerator pedal (not shown), and detects the amount of depression (operation amount) of the accelerator pedal by the driver as an accelerator operation amount.

  The air flow rate sensor 83 is provided upstream of the throttle valve 12 in the intake passage 6 and detects the flow rate of air flowing through the intake passage 6. The first intake pressure sensor 84 is provided in a portion of the intake passage 6 between the throttle valve 12 and the supercharger 13 and detects the pressure of gas passing through this portion. The second intake pressure sensor 85 is provided in a portion of the intake passage 6 between the intercooler 14 (supercharger 13) and the intake manifold 15, and detects the pressure of gas passing through this portion. The exhaust pressure sensor 86 is provided in a portion of the exhaust passage 7 between the exhaust manifold 22 and the catalytic converter 23, and detects the pressure of the gas passing through this portion.

  Next, the operation of the internal combustion engine 1 of the present embodiment will be described. The ECU 2 controls the operation of the internal combustion engine 1 by executing the control process shown in the flowchart of FIG. 3 and the control process shown in the flowchart of FIG.

  The control process shown in FIG. 3 includes an operation state of the intake valve drive mechanism 63 to control EGR gas (exhaust gas) and gas containing fresh air supplied to the combustion chamber 5 of each cylinder 4 of the internal combustion engine 1; An electric motor that drives the supercharger 13, the opening degree of the first EGR valve 29 and the second EGR valve 32, the opening degree of the throttle valve 12, the connection / disconnection of the first clutch 41 and the second clutch 54 of the EGR device 26. The number of rotations of 36 is controlled.

  The control of the operation state of the intake valve drive mechanism 63 is the selection of the intake cams 69A and 69B that drive the intake valve 61 to open and close and the control of the phase of the intake cams 69A and 69B. The target effective compression of the combustion chamber 5 of each cylinder 4 Based on the ratio. Control of the opening degree of the first EGR valve 29 and the second EGR valve 32 is performed based on the target EGR rate. The connection / disconnection of the first clutch 41 and the second clutch 54 and the control of the rotational speed of the electric motor 36 that drives the supercharger 13 are performed based on the target SC discharge amount that is the discharge amount of the supercharger 13.

  In the control process shown in the flowchart of FIG. 3, the ECU 2 first acquires the engine speed based on the detection signal of the crank angle sensor 81 and acquires the accelerator opening based on the detection signal of the accelerator sensor in step S1. .

  Next, in step S2, the ECU 2 sets the required torque of the internal combustion engine 1 based on the engine speed and the accelerator opening. The required torque is set based on the engine speed and the accelerator position with reference to a predetermined map set in advance, for example. As shown in FIG. 5, for example, the required torque is set so as to increase as the engine speed increases and to increase as the accelerator opening increases.

  In step S3, the ECU 2 determines the operating region of the internal combustion engine 1 based on the engine speed and the required torque. As shown in FIG. 6, the operation region is set to one of region A, region B, and region C according to the engine speed and the required torque. When the required torque is small, the operation region is set to a region A that is a low load region, when the required torque is large, the operation region is set to a region B that is a high load region, and when the required torque is medium, the operation region is set. Is set in region C as a middle load region sandwiched between region A and region B. Region A is an operation region where rotation of the rotation shaft 13A of the supercharger 13 is prohibited, and region B and region C are operation regions where rotation of the rotation shaft 13A of the supercharger 13 is allowed. A solid line which is a boundary between the region A and the region C shown in FIG. 6 represents a line where the supercharging pressure is zero.

  When the engine speed is constant, when the required torque changes from a small state to a large state, the operation region changes from region A to region B through region C. As the engine speed increases, the operation area is expanded in the area A and the area B is reduced. Thereby, when the required torque is constant, the operation region changes from region B to region A through region C as the engine speed increases.

  In step S4, the ECU 2 determines whether or not the operation region set in step S3 is the region A. When the determination is Yes, the process proceeds to step S5, where the ECU 2 controls to connect the first clutch 41 and controls to connect the second clutch 54. By connecting the first clutch 41, the rotation of the supercharger 13 is prohibited.

  Further, the ECU 2 refers to the map shown in FIG. 8 and sets the opening degree of the second EGR valve 32 based on the required torque. As shown in FIG. 8, the map defines the relationship between the required torque and the opening degree of the second EGR valve 32. When the operating region is in the region A, the opening degree of the second EGR valve 32 is fully open regardless of the required torque, and when the operating region is in the region C, the opening degree of the second EGR valve 32 is fully opened according to the increase in the required torque. When the operating region is in region C, the opening degree of the second EGR valve 32 is fully closed regardless of the required torque. Note that the map shown in FIG. 8 changes corresponding to the operation region that changes according to the engine speed. When the engine speed increases, the region C and the region B shift to the right side (the side where the required torque increases), and the graph representing the second EGR valve opening degree shifts corresponding to each region.

  When the operation region is in the region A, the second EGR valve 32 is fully opened, so that the fresh air that has passed through the throttle valve 12 and the gas that includes EGR gas supplied from the EGR passage are the first EGR passage 27 and the second EGR passage. It passes through the bypass passage constituted by 31 and the second EGR valve 32, bypasses the supercharger 13 and the intercooler 14, and is supplied to the combustion chamber 5.

  By connecting the second clutch 54, the crankshaft 37 and the planet carrier 47 of the planetary gear mechanism 35 are connected via the power transmission mechanism 50. In the region A, the first clutch 41 is connected and the sun gear 44 is fixed, so that driving force can be transmitted between the electric motor 36 and the crankshaft 37. Therefore, assist (cranking or the like) of the engine body 3 that transmits the driving force of the electric motor 36 to the crankshaft 37 and power generation that transmits the driving force of the crankshaft 37 to the electric motor 36 are possible. In another embodiment, the second clutch 54 may be disconnected in the region A.

  Next, in step S6, the ECU 2 sets a target fresh air amount, a target EGR rate, and a target effective compression ratio. The target fresh air amount is a target value of the fresh air amount that passes through the throttle valve 12 and flows into the combustion chamber 5. A value obtained by summing the fresh air amount and the EGR gas amount is defined as an air amount.

  FIG. 7A is a map that defines the relationship between the required torque and the target fresh air amount, and FIG. 7B is a map that defines the relationship between the required torque and the target EGR rate, and FIG. Is a map that defines the relationship between the required torque and the target effective compression ratio. A solid line and a broken line drawn with respect to a predetermined required torque in each diagram of FIG.

  The ECU 2 refers to the map shown in FIG. 7A and sets a target fresh air amount necessary for realizing the required torque based on the required torque. As shown in FIG. 7A, the map is set so that the target fresh air amount increases as the required torque increases. The target fresh air amount is a target amount of air that does not include EGR gas, and is a target amount of air that passes through the throttle valve 12.

  The ECU 2 refers to the map shown in FIG. 7B and sets a target EGR rate that is a target value of the EGR rate based on the required torque. As shown in FIG. 7B, when the required torque changes from a small value to a large value, the target EGR rate increases in response to an increase in the required torque in a region where the required torque is relatively small. The map is set so that the target EGR rate decreases as the required torque increases in the middle range, and then the target EGR rate increases again as the required torque increases in the relatively large required torque region. ing. The region where the required torque is relatively small corresponds to the operation region A, the region where the required torque is medium corresponds to the operation region C, and the region where the required torque is relatively large corresponds to the region B. .

  The ECU 2 refers to the map shown in FIG. 7C and sets a target effective compression ratio that is a target value of the effective compression ratio based on the required torque. The basic trend of the map shown in FIG. 7C is set so that the required torque is medium and the target effective compression ratio is the largest. The required torque when the target effective compression ratio becomes the largest corresponds to a range where the operation region is in region B and the required torque is relatively small.

  Next, in step S7, the ECU 2 corrects the target fresh air amount set in step S6. When EGR gas is introduced into fresh air, knocking is suppressed and thermal efficiency is improved, so that the amount of fresh air can be reduced. Therefore, the amount of fresh air is reduced according to the EGR rate, and the amount of fresh air corresponding to the required torque is set. The target fresh air amount is corrected based on the EGR rate and the target fresh air amount set in step S6. For example, referring to a map that defines the relationship between the EGR rate and the target fresh air amount correction value, the target fresh air amount correction value is set based on the EGR rate. Then, the corrected target fresh air amount may be set by subtracting the target fresh air amount correction value from the target fresh air amount set in step S6. Other methods refer to a map that defines the relationship between the EGR rate, target fresh air volume, and corrected target fresh air volume, and sets the corrected target fresh air volume based on the EGR rate and target fresh air volume You may make it do.

  Next, in step S8, the ECU 2 sets the target fresh air amount, the first intake pressure detected by the first intake pressure sensor 84, the engine speed, and the target values of the opening of the throttle valve 12 shown in FIG. The target throttle opening is set based on the target fresh air amount, the first intake pressure, and the engine speed with reference to a map that defines the relationship of the target throttle opening. The target fresh air amount used here is the corrected target fresh air amount set in step S7. As shown in FIG. 9, the map is set so that the target throttle opening increases as the target fresh air amount increases, and the target throttle opening decreases as the first intake pressure increases. Further, the map is set so that the target throttle opening increases as the engine speed increases.

  In step S8, the ECU 2 also sets the target first EGR valve, which is the target EGR rate, the first intake pressure or the second intake pressure, and the opening degree of the first EGR valve 29 shown in FIGS. 10 (A) and 10 (B). The target first EGR valve opening is set based on the target EGR rate and the second intake pressure with reference to a map that defines the relationship with the opening. When the operation region is the region A, the map shown in FIG. 10A is used, and when the operation region is the region B or C, the map shown in FIG. 10B is used. As shown in FIGS. 10A and 10B, the target first EGR valve opening increases as the target EGR rate increases, and the lower the first intake pressure or the second intake pressure (the negative pressure decreases). The target first EGR valve opening is set so as to decrease).

  In step S8, the ECU 2 sets driving amounts of the variable valve lift mechanism 66 (VTEC) and the variable valve phase mechanism 65 (VTC) for realizing the target effective compression ratio. The ECU 2 selects one of the large lift intake cam 69A and the small lift intake cam 69B based on the target effective compression ratio, and sets the driving amount of the variable valve lift mechanism 66 for using the selected intake cam. Further, the ECU 2 sets the drive amount of the valve phase variable mechanism 65 based on the target effective compression ratio and the selected intake cams 69A and 69B.

  Further, the ECU 2 controls the throttle valve 12, the target throttle valve opening, the target first EGR valve opening, the valve lift variable mechanism 66 (VTEC) and the valve phase variable mechanism 65 (VTC) in order to realize the drive amounts. The first EGR valve 29, the variable valve lift mechanism 66, and the variable valve phase mechanism 65 are controlled.

  When the determination in step S4 is No, that is, when the operation region is the region B or the region C, the ECU 2 controls to disconnect the first clutch 41 and connects the second clutch 54 in step S9. Control. When the first clutch 41 is disconnected, the supercharger 13 is allowed to rotate.

  By connecting the second clutch 54, the crankshaft 37 and the planet carrier 47 of the planetary gear mechanism 35 are connected via the power transmission mechanism 50. As a result, the driving force can be transmitted between the crankshaft 37, the rotary shaft 36A of the electric motor 36, and the rotary shaft 13A of the supercharger 13 via the power transmission mechanism 50 and the planetary gear mechanism 35.

  Further, the ECU 2 refers to the map shown in FIG. 8 and sets the opening degree of the second EGR valve 32 based on the required torque. As shown in FIG. 8, when the operating region is in region C, the second EGR valve 32 is set so that the opening degree decreases as the required torque increases, and when the operating region is in region B, the second EGR valve 32 is Regardless of the required torque, it is set to fully closed. When the opening degree of the second EGR valve 32 decreases, the fresh air that has passed through the throttle valve 12 and the gas that includes EGR gas supplied from the EGR passage pass through the supercharger 13 and the intercooler 14 and are supplied to the combustion chamber 5. The flow rate increases.

  By controlling the second EGR valve 32 in this manner, when the operating state is in the region C, the fresh air that has passed through the throttle valve 12 passes through the supercharger 13 and the intercooler 14, and the first EGR passage. 27 and the flow path passing through the second EGR passage 31, and the EGR gas passes through the second EGR passage 31 and is supplied to the intake passage 6 from the downstream side of the supercharger 13. On the other hand, when the operating state is in the region B, all the fresh air that has passed through the throttle valve 12 passes through the supercharger 13 and the intercooler 14, and EGR gas passes through the first EGR passage 27 and is more than the supercharger 13. It is supplied to the intake passage 6 from the upstream side.

  Next, in step S10, the ECU 2 sets a target fresh air amount, a target EGR rate, and a target effective compression ratio. The setting method of the target fresh air amount, the target EGR rate, and the target effective compression ratio in step S10 is the same as the setting method in step S6.

  Next, in step S11, the ECU 2 corrects the target fresh air amount set in step S10. The purpose and processing of step S10 are the same as those of step S7.

  Next, in step S12, the ECU 2 sets the opening of the throttle valve 12, the opening of the first EGR valve 29, and the drive amounts of the variable valve lift mechanism 66 (VTEC) and the variable valve phase mechanism 65 (VTC). The method for setting the opening amount of the throttle valve 12, the opening amount of the first EGR valve 29, the valve lift variable mechanism 66 (VTEC) and the valve phase variable mechanism 65 (VTC) in step S12 is set in step S8. It is the same as the method. The throttle opening is set based on the target fresh air amount corrected in step S11.

  Next, in step S13, the ECU 2 refers to a map that defines the relationship between the required torque and the target SC discharge amount shown in FIG. 7D, and based on the required torque, the target value of the discharge amount of the supercharger 13 is determined. A target SC discharge amount is set. As shown in FIG. 7D, the target SC discharge amount is 0 in the range where the required torque corresponds to the region A, and the target SC discharge amount is equal to the required torque in the range where the required torque corresponds to the region C and the region B. The map is set so as to increase in accordance with the increase. The increase rate of the target SC discharge amount with respect to the required torque is different between the region C and the region B, and the increase rate in the region C is set larger than that in the region B.

  Further, the ECU 2 sets a target outlet pressure that is a target value of the outlet pressure of the supercharger 13 based on the target SC discharge amount. The target outlet pressure is set so as to increase as the target SC discharge amount increases.

  Next, in step S14, the ECU 2 corrects the target SC discharge amount and the target outlet pressure set in step S13. When the opening degree of the second EGR valve 32 decreases and the EGR gas passes through the supercharger 13, the ratio of fresh air in the gas passing through the supercharger 13 decreases. As a result, the amount of fresh air supplied to the combustion chamber 5 decreases. Therefore, correction is performed to increase the target SC discharge amount and the target outlet pressure in accordance with an increase in the amount of EGR gas passing through the supercharger 13. The correction of the target SC discharge amount and the target outlet pressure is performed based on the EGR rate, the opening degree of the second EGR valve 32, and the target SC discharge amount and the target outlet pressure set in step S13. For example, referring to a map that defines the relationship between the EGR rate and the opening degree of the second EGR valve 32 and the target SC discharge amount correction value, the target SC discharge amount correction value is determined based on the EGR rate and the opening degree of the second EGR valve 32. Set. Then, the corrected target SC discharge amount is set by adding the target SC discharge amount correction value to the target SC discharge amount set in step S13. In the map that defines the relationship between the EGR rate and the opening degree of the second EGR valve 32 and the target SC discharge amount correction value, the SC discharge amount correction value increases as the EGR rate increases, and the opening degree of the second EGR valve 32 increases. The SC discharge amount correction value is set to decrease as the value increases.

  In another method, referring to a map that defines the relationship between the EGR rate, the opening degree of the second EGR valve 32, the target SC discharge amount, and the corrected target SC discharge amount, the EGR rate, the opening degree of the second EGR valve 32, and The corrected target fresh air amount may be set based on the target SC discharge amount. The corrected target outlet pressure may be set based on the corrected target SC discharge amount.

  The corrected target outlet pressure is set to increase as the corrected target SC discharge amount increases.

  Next, the ECU 2 performs target SC discharge amount control in order to realize the target SC discharge amount in step S15. The target SC discharge amount control is executed according to the flowchart shown in FIG.

  As shown in FIG. 4, the ECU 2 first sets a target value that is a target value of the rotational speed of the rotating shaft 13A of the supercharger 13 based on the corrected target SC outlet pressure set in step S14 in step S21. Set the SC speed. The setting of the target SC speed is performed with reference to a map that defines the relationship between the target SC outlet pressure and the target SC speed. The map is set so that the target SC rotation speed increases as the target SC outlet pressure increases.

  Next, in step S22, the ECU 2 calculates an SC volume efficiency estimated value that is an estimated value of the volume efficiency of the supercharger 13 based on the target SC rotation speed and the target SC outlet pressure. The setting of the target SC rotational speed is performed based on a map that defines the relationship among the target SC rotational speed, the target SC outlet pressure, and the SC volume efficiency estimated value shown in FIG. In the map, the SC volume efficiency estimation value is set to be higher as the target SC rotational speed is higher or the target SC outlet pressure is higher.

  Next, in step S23, the ECU 2 calculates an SC discharge amount estimated value that is an estimated value of the discharge amount of the supercharger 13 based on the target SC rotational speed and the SC volume efficiency estimated value.

  Next, in step S24, the ECU 2 determines whether or not the estimated SC discharge amount estimated in step S23 matches the target SC discharge amount. Note that the fact that the estimated SC discharge amount matches the target SC discharge amount does not mean that the SC discharge amount is exactly equal, but means that the absolute value of the difference falls within a predetermined value.

  If the determination result in step S24 is Yes, the ECU 2 sets a target motor rotational speed that is the rotational speed of the electric motor 36 for realizing the target SC rotational speed in step S25. The electric motor 36 is controlled so as to realize the rotational speed.

  If the determination result in step S24 is No, the target SC speed is changed in step S26. The target SC rotation speed is changed by reducing the target SC rotation speed by a predetermined value when the estimated SC discharge amount is larger than the target SC discharge amount, and by changing the target SC rotation amount when the estimated SC discharge amount is smaller than the target SC discharge amount. This is done by increasing the SC rotational speed by a predetermined value. After performing the process of step S26, the process returns to step S22.

  The process of step S26, step S22, and step S23 is repeated until the determination result in step S24 becomes Yes. Thereby, the discharge amount of the supercharger 13 is controlled to be equal to the target SC discharge amount.

  Below, the action | operation of the internal combustion engine 1 which concerns on this embodiment is demonstrated. In the internal combustion engine 1, the operation region is set to one of regions A to C based on the required torque and the engine speed, and the supercharger 13, the EGR device 26, and the intake valve drive mechanism 63 are set in accordance with each region. Be controlled.

  When the operation region is in region A, the rotation of the supercharger 13 is prohibited. At this time, since the second EGR valve 32 as a bypass valve is opened, fresh air that has passed through the throttle valve 12 passes through a bypass passage constituted by a part of the first EGR passage 27 and the second EGR passage 31, It flows around the feeder 13. The EGR gas passes through the first EGR passage 27 and the second EGR passage 31 and is supplied to the intake passage 6 from the downstream portion of the supercharger 13.

  In the region A, the amount of fresh air and the effective compression ratio are controlled to increase as the required torque increases, and the output of the internal combustion engine 1 increases. The EGR rate increases as the required torque increases in the range where the required torque in the region A is small, and decreases as the required torque increases in the range where the required torque in the region A is large. As a result, the EGR gas amount is increased to reduce the pumping loss when the required torque in the region A is medium, and the EGR gas amount can be reduced to increase the output when the required torque is large. .

  When the operation region is in region B and region C, the supercharger 13 can be rotated. In the region C, the opening degree of the second EGR valve 32 decreases as the required torque increases, the flow rate of fresh air and EGR gas passing through the second EGR passage 31 decreases, and fresh air and EGR gas are mainly sucked. It passes through the supercharger 13 in the passage 6. When the required torque increases and the operation region becomes region B, the second EGR valve 32 is fully closed, and all fresh air and EGR gas pass through the supercharger 13.

  In the region C, since the supercharger 13 starts rotating, the SC discharge amount increase amount with respect to the increase in the required torque is set larger than that in the region B. This characteristic is realized by the map shown in FIG. In the region B and the region C, the fresh air amount and the EGR rate increase as the required torque increases, and the effective compression ratio is controlled to decrease, so that the output of the internal combustion engine 1 increases. As a result, even if the required torque increases and the amount of fresh air increases, the occurrence of knocking is suppressed due to an increase in the EGR rate and a decrease in the effective compression ratio due to the variable valve phase mechanism 65 and the variable valve lift mechanism 66. . Further, by cooling the EGR gas by the EGR cooler 28 and lowering the intake air temperature, the knocking suppression effect can be further improved.

  Thus, the EGR rate is controlled for the purpose of reducing the pumping loss in the region A, and is controlled for the purpose of suppressing knocking in the regions B and C. The effective compression ratio is controlled for the purpose of improving thermal efficiency in the regions A and C, and is controlled for the purpose of suppressing knocking in the region B.

  Since the amount of fresh air is corrected and reduced according to the EGR rate, excessive cooling of the internal combustion engine 1 by fresh air is suppressed, and a decrease in thermal efficiency is suppressed.

  In the regions B and C, the discharge amount of the supercharger 13 is corrected according to the EGR rate and the opening degree of the second EGR valve 32, so a fresh air amount corresponding to the required torque is ensured. When the discharge amount of the supercharger 13 is set and the EGR gas passes through the supercharger 13, the amount of fresh air that should pass through the supercharger 13 is reduced by the flow rate of the EGR gas. By correcting the discharge amount of the supercharger 13 in accordance with the EGR rate and the opening degree of the second EGR valve 32, a desired fresh air amount is secured.

(Second Embodiment)
In the second embodiment, the operation region setting method is different from the first embodiment, and the operation region is performed based on the map of FIG. 12 instead of the map of FIG. Other configurations and control procedures of the internal combustion engine 1 according to the second embodiment are the same as those in the first embodiment.

  As shown in FIG. 12, in the map of the operation region according to the second embodiment, the region B is expanded to the side where the required torque is lower than the line where the supercharging pressure is 0. The region A is defined in a region where the engine speed is not more than a predetermined value at a medium level and the required torque is not more than a specified value which is relatively low. Region C is set at the boundary between region A and region B.

  In the area A, as in the first embodiment, the first clutch 41 is connected, the rotation of the supercharger 13 is prohibited, and the second EGR valve 32 is set to fully open. In the region B, as in the first embodiment, the first clutch 41 is disengaged, the rotation of the supercharger 13 is allowed, and the second EGR valve 32 is set to be fully closed. In the region C, as in the first embodiment, the first clutch 41 is disengaged and the supercharger 13 is allowed to rotate, and the opening degree of the second EGR valve 32 is set according to the required torque.

  In the second embodiment, the regions B and C in which the supercharger 13 can rotate are also set when the supercharging pressure is lower than zero. Therefore, in regions B and C, in the region corresponding to the portion where the supercharging pressure is lower than 0, the rotating shaft 13A of the supercharger 13 is rotated by the suction negative pressure of the cylinder 4. The rotation of the supercharger 13 is transmitted to the electric motor 36 via the planetary gear mechanism 35 and becomes a driving force for power generation or transmitted to the crankshaft 37 to assist the rotation of the crankshaft 37. In this way, the energy normally consumed as the pumping loss by the supercharger 13 is transmitted to the electric motor 36 and the crankshaft 37 and used effectively.

  FIG. 13 is a map for setting the target fresh air amount, the target EGR rate, the target effective compression ratio, and the target SC discharge amount based on the required torque in the second embodiment. As shown in FIG. 13D, in the second embodiment, discharge by the supercharger 13 occurs from a state where the required torque is low.

  The map relating to the setting of the operation region according to the first and second embodiments described above may be selectable between them. For example, the map according to the first embodiment (FIG. 7) and the map according to the second embodiment (FIG. 12) may be selected according to the driver's operation and driving conditions.

  DESCRIPTION OF SYMBOLS 1 ... Internal combustion engine, 2 ... ECU, 3 ... Engine main body, 5 ... Combustion chamber, 6 ... Intake passage, 7 ... Exhaust passage, 12 ... Throttle valve, 13 ... Supercharger, 14 ... Intercooler, 26 ... EGR device, 27 1st EGR passage, 29 ... 1st EGR valve, 31 ... 2nd EGR passage, 32 ... 2nd EGR valve, 35 ... planetary gear mechanism, 36 ... electric motor, 37 ... crankshaft, 41 ... 1st clutch, 44 ... sun gear, 45 ... Internal gear, 46 ... Planet gear, 47 ... Planet carrier, 50 ... Power transmission mechanism, 54 ... Second clutch, 63 ... Intake valve drive mechanism, 64 ... Exhaust valve drive mechanism, 65 ... Valve phase variable mechanism, 66 ... Valve lift variable mechanism, 69A ... large lift intake cam, 69B ... small lift intake cam, 81 ... crank angle sensor, 83 ... air flow sensor, 84 ... first intake pressure sensor, 85 ... second intake pressure Capacitors, 86 ... exhaust pressure sensor

Claims (6)

A control device for an internal combustion engine including a mechanical supercharger capable of changing a discharge amount,
A first EGR valve provided in an EGR passage connecting an exhaust passage and an intake passage of the internal combustion engine;
It has an effective compression ratio variable mechanism that changes the effective compression ratio by changing the opening and closing timing of the intake valve,
An internal combustion engine control apparatus that controls the supercharger, the first EGR valve, and the effective compression ratio variable mechanism based on a required load required for the internal combustion engine.   In a high load region where the required load is high, an EGR rate that is a ratio of an EGR gas amount to a fresh air amount is increased with respect to an increase in the required load, and the discharge amount of the supercharger is increased. The control apparatus for an internal combustion engine according to claim 1.   The high-load region where the required load is high, the effective compression ratio is decreased and the discharge amount of the supercharger is increased with an increase in the required load. Control device for internal combustion engine. The EGR passage branches from the first EGR passage connecting the exhaust passage and a portion upstream of the supercharger in the intake passage, and downstream from the supercharger in the intake passage. A second EGR passage connected to the side portion and a second EGR valve provided in the second EGR passage, wherein the first EGR valve is more exhausted than the portion of the first EGR passage where the second EGR passage branches. Provided on the side,
In the low load region where the required load is low, rotation of the supercharger is prohibited and the second EGR passage is opened, and in the high load region where the required load is high, rotation of the supercharger is allowed and the second EGR passage is opened. 4. The control device for an internal combustion engine according to claim 2, wherein is closed.   5. The control device for an internal combustion engine according to claim 4, wherein in the high load region, correction is performed so as to increase the discharge amount of the supercharger as the EGR rate increases. The supercharger is connected to a crankshaft and an electric motor of the internal combustion engine via a planetary gear mechanism,
The planetary gear mechanism rotatably supports a sun gear connected to the rotating shaft of the supercharger, an internal gear connected to the electric motor, and the planetary gear meshing with the sun gear and the internal gear, The control device for an internal combustion engine according to any one of claims 1 to 5, further comprising a planetary carrier connected to the crankshaft.

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