JP4403122B2 - Control device for internal combustion engine - Google Patents

Description

  The present invention relates to a control device for an internal combustion engine, and more particularly to a control device for an internal combustion engine of a torque base control system that controls an air amount, a fuel injection amount, an ignition timing, and the like based on a target torque.

  As a control device for an internal combustion engine (hereinafter sometimes referred to as an engine), a target output torque of the internal combustion engine is calculated, a set air-fuel ratio is calculated based on the calculated target output torque and the engine rotational speed, and the target output torque is calculated. The target cylinder air amount is calculated based on the air-fuel ratio and the set air-fuel ratio, the target intake air amount is calculated based on the target cylinder air amount and the engine speed, and the predetermined advance characteristic is filtered with respect to the target intake air amount. Some control the intake air amount on the basis of the target intake air amount subjected to the above (for example, Patent Document 1).

  Examples of the control element that changes the intake air amount include the characteristics of the valve lift and the like, and there is a variable valve mechanism, and an element that controls the intake air amount by controlling the valve lift amount (and the valve operating angle) (for example, Patent Document 2).

  As a new logic engine control system, a torque base (torque demand) control system has been put into practical use. The background of the development of this engine control system is that the torque required from the outside of the engine to the engine side has increased as in the case of traction control in a vehicle engine, and that the processing unit has become necessary. The throttle has been put into practical use.

  Specifically, in addition to the driver's accelerator operation, external control torque such as idle request torque and vehicle body control is comprehensively determined to set the target engine torque, and the fuel injection amount and It controls the amount of intake air.

  Since the engine torque largely depends on the fuel injection amount, fuel control is important for realizing the target engine torque. At the same time, it is an essential requirement to adjust the air-fuel ratio to a desired value from the viewpoint of highly efficient use of the exhaust gas purification catalyst.

  That is, in torque-based control, it is important to achieve both control accuracy of fuel control and air-fuel ratio control. There are the following two types of methods proposed as torque-based control depending on the method of determining the fuel injection amount.

  One of them is an air-driven (preceding) type that determines the fuel injection amount after measuring the actual intake air amount (for example, Patent Document 3), and the other is based directly on the target torque calculation result. This is a fuel-driven (preceding) type that determines the fuel injection amount (for example, Patent Document 4).

  In air-driven torque-based control, the target air amount is calculated based on the target torque calculation result, and the target throttle opening command signal is sent to the electric throttle drive unit to obtain the target air amount. The actual air amount sucked into the cylinder (combustion chamber) is measured by an air amount sensor such as an air flow sensor, and the fuel injection amount is determined based on the measured actual air amount and the target air-fuel ratio.

  The air-driven torque-based control has a feature that air-fuel ratio accuracy is guaranteed because the fuel injection amount is determined based on the actual air amount. However, since the fuel injection amount that determines the torque is determined via the air amount, the generated torque may greatly deviate from the target torque depending on the accuracy of the air amount control.

  On the other hand, in fuel-driven torque-based control, based on the target torque calculation result, the target fuel injection amount and the target air amount are determined so as to achieve a desired air-fuel ratio, and the injector and the electric throttle that respectively perform fuel injection A command signal corresponding to is transmitted.

In the fuel-driven torque-based control, there is a drawback that a desired air-fuel ratio cannot be obtained if the fuel injection amount and the air amount are not realized as target values. In particular, with respect to the intake air amount, it is difficult to make the target air amount and the actual air amount coincide with each other, and improving the accuracy of air amount control becomes a major issue.
Japanese Patent Laid-Open No. 11-22511 JP 2004-045549 A JP-A-10-89140 JP-A-1-313636

  In the prior art, various actuators mounted on an internal combustion engine are controlled based on the output of an air amount sensor according to a predetermined operating state. However, since the air amount sensor is located upstream of various actuators mounted on the internal combustion engine, such as a variable intake valve, it can measure only the air flow after operation of the various actuators. For this reason, in particular, the amount of intake air to the cylinder during overrun cannot be measured accurately. For this reason, the fuel injection amount and the ignition timing cannot be optimally controlled.

  The present invention has been made in view of the above points, and the object of the present invention is to accurately estimate the amount of air in the cylinder that changes according to the operation of various actuators during transient operation, It is an object to provide a control device for an internal combustion engine that optimally controls the timing.

  An internal combustion engine control device according to the present invention includes a throttle control device that controls the amount of air to the internal combustion engine using a throttle valve, an intake valve control device that operates the intake valve to a predetermined position, and an operating state of the intake valve. In an internal combustion engine control device having an intake valve sensor that performs fuel supply, a fuel injection device that supplies fuel, and an ignition device that performs ignition, an intake valve passage that estimates an intake valve passage air amount according to an output of the intake valve sensor An air amount estimation model unit, a cylinder residual gas estimation model unit that estimates a cylinder residual gas amount according to the output of the intake valve sensor, and an intake valve passage air estimated by the intake valve passage air amount estimation model unit A cylinder intake pressure estimation model unit for estimating the cylinder intake pressure according to the amount, and the cylinder intake pressure An in-cylinder intake air pressure estimated by the estimation model unit and an in-cylinder air amount estimation model unit for estimating the cylinder air amount according to the cylinder residual gas amount estimated by the cylinder residual gas estimation model unit Then, at least one of fuel injection by the fuel injection device and ignition timing by the ignition device is controlled based on the cylinder air amount estimated by the cylinder air amount estimation model unit.

  The control apparatus for an internal combustion engine according to the present invention preferably has a purge air flow rate calculation unit that calculates a purge air flow rate by a purge device that purges the evaporated gas of the fuel tank into the engine intake system, and the purge air flow rate calculation unit Based on the calculated purge air flow rate, the cylinder air amount estimated by the cylinder air amount estimation model unit is corrected as a combustion contributing air amount.

  The control device for an internal combustion engine according to the present invention preferably has an EGR air flow rate calculation unit for calculating an EGR air flow rate by the exhaust gas recirculation device, and the EGR air flow rate is calculated by the EGR air flow rate calculation unit. The cylinder air amount estimated by the cylinder air amount estimation model unit is corrected as the combustion contributing air amount.

  The control device for an internal combustion engine according to the present invention further includes a target cylinder air amount calculation model unit that calculates a target cylinder air amount based on the target combustion torque, and the throttle control device and the intake valve control device include: The operation is performed so that the difference between the target cylinder air amount calculated by the target cylinder air amount estimation model unit and the cylinder air amount estimated by the cylinder air amount estimation model unit is reduced.

  The control apparatus for an internal combustion engine according to the present invention preferably corrects the estimation model by each of the estimation model units according to the intake pipe pressure detected by the intake pipe pressure sensor or the air-fuel ratio detected by the air-fuel ratio sensor.

  The control apparatus for an internal combustion engine according to the present invention preferably corrects the estimation model so that a deviation between the pressure of the intake collector calculated from the result of the estimation model by the estimation model unit and the pressure of the intake pipe pressure sensor becomes small. To do.

  An internal combustion engine control device according to the present invention includes an intake valve control device that operates an intake valve to a predetermined position, an intake valve sensor that detects an operation state of the intake valve, a fuel injection device that supplies fuel, and ignition. In an internal combustion engine control device having an ignition device to perform, an intake valve air flow rate calculation means for calculating an intake valve passing air amount according to an output of the intake valve sensor, and an intake air calculated by the intake valve air flow rate calculation unit In-cylinder intake pressure calculating means for calculating the intake pressure in the cylinder according to the valve air flow rate, and in-cylinder air flow rate for calculating the in-cylinder air flow rate according to the in-cylinder intake pressure calculated by the in-cylinder intake pressure calculation means Calculates the purge air flow rate by the calculation means and the purge device that purges the fuel tank evaporative gas to the engine intake system An air flow rate calculating means, an EGR air flow rate calculating means for calculating an EGR air flow rate by the exhaust gas recirculation device, and an in-cylinder residual gas flow rate by a valve overlap according to the output of the intake valve sensor A residual gas flow rate calculating means; a cylinder air flow rate calculated by the cylinder air flow rate calculating means; a purge air flow rate calculated by the purge air flow rate calculating means; and an EGR air flow rate calculated by the EGR air calculating means. Combustion contribution air amount calculation means for calculating the combustion contribution air amount from the cylinder residual gas flow rate calculated by the cylinder residual gas flow rate calculation means, and the combustion contribution air calculated by the combustion contribution air amount calculation means The fuel injection by the fuel injection device and the ignition timing by the ignition device based on the quantity At least one to one control.

  The control apparatus for an internal combustion engine according to the present invention preferably includes an intake collector pressure estimation calculating means for estimating the pressure of the intake collector and an intake pipe pressure sensor for detecting the intake pipe pressure, and the intake collector pressure Used for calculation of the intake valve air flow rate by the intake valve air flow rate calculation means so that the deviation between the intake collector estimated pressure estimated by the estimation calculation means and the intake pipe pressure detected by the intake pipe pressure sensor becomes small. Correct the intake valve opening area.

  The control apparatus for an internal combustion engine according to the present invention preferably includes an intake collector pressure estimation calculating means for estimating the pressure of the intake collector and an intake pipe pressure sensor for detecting the intake pipe pressure, and the intake collector pressure An EGR valve used for the calculation of the EGR air flow rate by the EGR air flow rate calculation unit so that the deviation between the intake collector estimated pressure estimated by the estimation calculation means and the intake pipe pressure detected by the intake pipe pressure sensor becomes small. Correct the opening area.

  The control apparatus for an internal combustion engine according to the present invention preferably includes an intake collector pressure estimation calculating means for estimating the pressure of the intake collector and an intake pipe pressure sensor for detecting the intake pipe pressure, and the intake collector pressure Calculation of the residual gas flow rate in the cylinder by the residual gas flow rate calculation means in the cylinder so that the deviation between the intake collector estimated pressure estimated by the estimation calculation means and the intake pipe pressure detected by the intake pipe pressure sensor becomes small. The valve overlap opening area used for the correction is corrected.

  The control apparatus for an internal combustion engine according to the present invention preferably includes an intake collector pressure estimation calculating means for estimating the pressure of the intake collector and an intake pipe pressure sensor for detecting the intake pipe pressure, and the intake collector pressure The purge opening used for calculating the purge air flow rate by the purge air flow rate calculation means so that the deviation between the intake collector estimated pressure estimated by the estimation calculation means and the intake pipe pressure detected by the intake pipe pressure sensor becomes small. Correct the area.

  The present invention uses the above-described various estimation models as engine models, and implements an engine model that simulates engine operation in the engine control device, predicts each parameter after a predetermined period of time using the engine model, and the prediction result is a target value. The cylinder inflow is determined by the cylinder air amount estimation model using the engine model during transient operation where the operating state of each actuator changes rapidly. By obtaining the fuel injection amount and the ignition timing based on the air amount, it is possible to prevent torque fluctuation and exhaust deterioration during transient operation.

An embodiment of a control device for an internal combustion engine of the present invention will be described in detail with reference to the drawings.
FIG. 1 shows a system configuration of a fuel injection type internal combustion engine to which a control device of one embodiment of the present invention is applied.

  The internal combustion engine 10 of the present embodiment is configured as a V-type engine. The internal combustion engine 10 has a piston 13 in a cylinder bore 12 formed in the engine block 11, and defines a plurality of combustion chambers (cylinder chambers) 14 in each bank. The piston 13 is drivingly connected to the crankshaft 44 by a connecting rod 43.

  A crank angle sensor 45 that detects the rotation angle (crank angle) of the crankshaft 44 and a water temperature sensor 46 that detects the coolant temperature are attached to the engine block 11.

  The air cleaner 15 is provided with an air amount sensor 16 for measuring the amount of intake air and an intake air temperature sensor 17 for detecting the temperature of the intake air.

  Air is taken in from the air cleaner 15 and passes through a throttle valve assembly having a throttle valve 18 for controlling the amount of intake air, that is, a throttle body 19 and an intake pipe 20A, and enters an intake collector (surge tank) 20. The throttle valve 18 is an electric throttle control device that controls the amount of air to the combustion chamber 14, a so-called electric throttle.

  A throttle sensor 21 that detects the opening of the throttle valve 18 is attached to the throttle body 19. An intake pipe pressure sensor 49 for detecting the intake pipe pressure is attached to the intake pipe 20A.

  An intake branch pipe 22 is connected to the intake collector 20 to supply air to each cylinder (combustion chamber 14) of the internal combustion engine 10. A fuel injection valve 23 for each cylinder is attached to the intake branch pipe 22 as a fuel injection device that supplies fuel.

  On the intake side of the internal combustion engine 10, an intake valve 25 that opens and closes the intake port 24, and an intake variable valve mechanism 26 that can variably operate the intake valve 25 as an intake valve control device that operates the intake valve 25 to a predetermined position are provided. ing. Although not shown in FIG. 1, an intake valve sensor 48 (see FIG. 3) for detecting the operating state of the intake valve 25 is provided on the engine intake side.

  On the exhaust side of the internal combustion engine 10, an exhaust valve 28 that opens and closes an exhaust port 27 and an exhaust variable valve mechanism 29 that can variably operate the exhaust valve 28 are provided. An exhaust pipe 31 to which a catalytic converter 30 is attached is connected to the exhaust port 27 on the way. An air-fuel ratio sensor 41 is attached upstream of the catalytic converter 30, and an oxygen sensor 42 is attached downstream of the catalytic converter 30.

  An exhaust gas recirculation passage 32 is provided in the internal combustion engine 10. An EGR valve 33 is attached to the exhaust gas recirculation passage 32. The EGR valve 33 controls the amount of EGR that returns a part of the exhaust gas to the intake system.

  The fuel in the fuel tank 34 is pressurized by the fuel pump 35, and regulated and supplied by the pressure regulator 47 to the fuel injection valve 23. The fuel tank 34 is provided with a canister 36 that adsorbs the evaporated gas in the fuel tank 34 as a purge device for purging the evaporated gas in the fuel tank 34 to the engine intake system.

  The fuel adsorbed by the canister 36 is returned to the intake system through a purge passage 37 and a purge valve 38 provided as a purge device for purging the evaporated gas in the fuel tank 34 to the engine intake system.

  An ignition plug 39 is attached to the internal combustion engine 10 for each combustion chamber 14 as an ignition device. The spark plug 39 is applied with a discharge voltage by the ignition coil 40 and ignites a mixture of fuel and air in the combustion chamber 14 by spark discharge.

  The internal combustion engine 10 has an electronically controlled engine control device 100 (hereinafter referred to as ECU) as a control device. The ECU 100 receives sensor signals from the air amount sensor 16, the intake air temperature sensor 17, the throttle sensor 21, the air-fuel ratio sensor 41, the oxygen sensor 42, the crank angle sensor 45, and the water temperature sensor 46, performs arithmetic processing, and performs throttle processing. Control command signals are output to each of the valve 18, fuel injection valve 23, pressure regulator 47, ignition coil 40, intake variable valve mechanism 26, exhaust variable valve mechanism 29, EGR valve 33, and purge valve 38.

  As shown in FIG. 2, the ECU 100 is constituted by a computer including an input circuit 101, an A / D conversion unit 102, a CPU (central processing unit) 103, a ROM 104, a RAM 105, and an output circuit 106.

  The input circuit 101 takes in signals output from the above-described sensors as input signals. When this input signal is an analog signal (a signal from the throttle sensor 21 or the water temperature sensor 46), the input circuit 101 removes a noise component from the signal and outputs the signal to the A / D converter 102. To do.

  The CPU 103 inputs sensor signals A / D converted by the input circuit 101 and the A / D converter 102 and executes control logic (program) stored in the ROM 104 to execute control, diagnosis, and the like.

  The calculation result and A / D conversion result calculated by the CPU 103 are temporarily stored in the RAM 105, and a control command signal based on the calculation result is sent from the output circuit 106 to actuators such as the fuel injection valve 23 and the ignition coil 40. Is output and used to control these actuators.

  As shown in FIG. 3, the ECU 100 performs the throttle passage air amount estimation model unit 201, the intake valve passage air amount estimation model unit 202, and the cylinder intake air pressure estimation by software processing by the CPU 103 executing a computer program. Model unit 203, cylinder residual gas estimation model unit 204, cylinder air amount estimation model unit 205, fuel injection control model unit 206, ignition timing control model unit 207, target cylinder air amount calculation model unit 208, throttle control model unit 209, an engine model by the intake valve control model unit 210 is configured.

  The throttle passage air amount estimation model unit 201 estimates the front-rear pressure of the throttle control device 51 (throttle valve 18) and the throttle passage air amount by mathematical calculation based on the output of the throttle sensor 21.

  The intake valve passing air amount estimation model unit 202 estimates the front-rear pressure of the intake valve control device 52 (intake valve 25) and the intake valve passing air amount by mathematical calculation based on the output of the intake valve sensor 48.

  The cylinder intake pressure estimation model unit 203 estimates the cylinder intake pressure by mathematical calculation based on the intake valve passage air amount estimated by the intake valve passage air amount estimation model unit 202.

  The cylinder residual gas estimation model unit 204 estimates the cylinder residual gas amount by mathematical calculation based on the output of the intake valve sensor 48.

  The cylinder air amount estimation model unit 205 is configured to determine whether the cylinder interior air pressure is estimated based on the cylinder intake air pressure estimation model unit 203 and the cylinder residual gas amount estimated by the cylinder residual gas estimation model unit 204. The intake air amount is estimated by mathematical calculation.

  The in-cylinder intake air amount estimated by the in-cylinder air amount estimation model unit 205 is passed to the fuel injection control model unit 206 and the ignition timing control model unit 207, and is used to calculate the ignition timing and the fuel injection amount. In other words, the ignition timing and the fuel injection amount are calculated using at least the cylinder inflow air amount estimated by the cylinder air amount estimation model unit 205.

  The fuel injection control model unit 206 outputs a control command signal (drive signal) to the fuel injection control device 53 (fuel injection valve 23), and the ignition timing control model unit 207 transfers to the ignition timing control unit 54 (ignition coil 40). A control command signal (drive signal) is output.

  In this embodiment, in this way, various estimation models are used as engine models, and the engine model for simulating engine operation is mounted on the ECU 100, and each parameter after a predetermined time has been predicted by the engine model. Each actuator is controlled so that becomes a target value.

  The target cylinder air amount calculation model unit 208 calculates the target cylinder air amount based on the target combustion torque.

  The throttle control model unit 209 has a deviation between the cylinder air amount estimated by the cylinder air amount estimation model unit 205 and the target cylinder air amount based on the target combustion torque calculated by the target cylinder air amount calculation model unit 208. And an operation amount signal is output to the slot control device 51 so that the deviation decreases (zero).

  The intake valve control model unit 210 calculates the difference between the cylinder air amount estimated by the cylinder air amount estimation model unit 205 and the target cylinder air amount based on the target combustion torque calculated by the target cylinder air amount calculation model unit 208. A deviation is calculated, and an operation amount signal is output to the intake valve control device 52 (intake variable valve mechanism 26) so that the deviation decreases (zero).

  The engine model error described above is corrected based on the results of various sensors. In this embodiment, various estimation models are corrected according to the outputs of the intake pipe pressure sensor 49, the air-fuel ratio sensor 41, the intake air temperature sensor 17, and the water temperature sensor 46. Further, the estimation model is modified so that the deviation between the pressure of the intake collector 20 calculated from the results of various estimation models and the pressure of the intake pipe pressure sensor 49 becomes small.

  Next, details of the calculation processing of the combustion contribution air amount will be described with reference to the calculation processing block diagram shown in FIG. 4 and the flowchart shown in FIG.

  As shown in FIG. 4, the calculation process of the combustion contribution air amount is performed by the cylinder air flow rate calculation unit 2051 (cylinder air amount estimation model). Unit 205), intake valve air flow rate calculation unit 2052 (intake valve passage air amount estimation model unit 202), throttle air flow rate calculation unit 2053 (throttle passage air amount estimation model unit 201), intake collector unit estimated pressure calculation unit 2054, EGR air flow rate calculation unit 2055, residual gas air flow rate calculation unit 2056 (in-cylinder residual gas estimation calculation unit 204), combustion contribution air amount calculation unit 2057, exhaust pipe air flow rate calculation unit 2058, purge air Flow rate calculation unit 2059 and in-cylinder intake pressure calculation unit 2060 (in-cylinder intake pressure estimation model unit 203) , It is performed by an exhaust pipe pressure calculation unit 2061.

  The specific calculation contents performed by each calculation unit of the cylinder air amount estimation model unit 205 described above will be clarified in the description of the calculation processing flow (FIG. 5) described below.

  First, various variables are initialized (step S501). The initial value of the air quantity related variable is 0, and the initial value of the pressure related variable is atmospheric pressure. The initial value of the temperature related variable is set to a predetermined value.

  After the variable initialization process, the engine speed NDATA, which is basic information necessary for calculating the air amount of the engine, is fetched (step S502).

Next, the in-cylinder air flow rate calculation unit 2051 calculates the in-cylinder air flow rate QEXTV that is the amount of air taken in by the engine (step S503). The calculation formula for calculating the in-cylinder air flow rate QEXTV is obtained according to the following simplified formula based on the literature of the internal combustion engine.
QEXTV = ETAV / VL / NDATA
However, ETAV: suction efficiency, VL: engine displacement, NDATA: engine speed

The engine speed NDATA is obtained from the output signal of the crank angle sensor 45.
The inhalation efficiency ETAV is obtained by the following formula.
ETAV = PCYL / (84800 + 173 · TCYL) · K1-PEXTUB / (84800 + 173 · TCYL) · 0.87 · K2
Where, PCYL: cylinder intake pressure, TCYL: cylinder air estimated temperature, PEXTUB: engine exhaust pipe pressure, K1 = ε / (ε-1), K2 = 1 / (ε-1), ε: engine compression ratio

  When the engine is started, the cylinder intake pressure PCYL is equivalent to atmospheric pressure, the cylinder air estimated temperature TCYL is equivalent to the outside air temperature, the engine is rotated by the starter, the engine speed NDATA is determined, and the process of the cylinder air flow rate calculation unit 2051 is performed. Thus, the intake air amount QEXTV of the engine is determined.

Next, the intake valve opening area AINTV is taken from the intake valve sensor 48 (step S504), and the intake valve air flow rate QINTV passing through the intake valve is obtained from the following equation (step S05).
QINTV = AINTV / CINTV / KAIRD / CPMINTV / SONIC
However,
AINTV: Intake valve opening area CINTV: Intake valve flow coefficient KAIRD: Air density CPMINTV: Intake valve pressure ratio SONIC: Sound velocity of air

Here, the air density KAIRD is obtained according to the following equation.
KAIRD = 1.293 ・ 273 / (273 + TINTV) ・ PATM
TINTV: Intake valve portion estimated air temperature PATM: Atmospheric pressure The intake valve portion pressure ratio CPMINTV is obtained according to the following equation.

但し、Ｃｐ１：圧力比、ｋ：気体の比熱比

However, Cp1: Pressure ratio, k: Specific heat ratio of gas

The pressure ratio Cp1 is obtained according to the following formula.
Cp1 = PCYL / PM
However, PCYL: In-cylinder intake pressure, PM: Intake collector estimated pressure (initial value is atmospheric pressure)

Here, the in-cylinder intake pressure PCYL can be obtained by the in-cylinder intake pressure calculation unit 2060 according to the following expression because the difference between the outflow amount and the inflow amount becomes the pressure change.
PCYL = KPCYL ・ (QINTV-QEXTV) + PCYL [Z]
However,
KPCYL: Pressure gradient coefficient QINTV: Intake valve air flow rate (initial value is 0)
QEXTV: Engine intake air amount PCYL [Z]: Previously calculated value of PCYL (initial value is atmospheric pressure)

  Next, the throttle air flow rate QTVO is calculated by the slot air flow rate calculation unit 2053 (step S506). In the present embodiment, since the air amount sensor 16 is arranged on the upstream side of the throttle valve 18, the throttle air flow rate QTVO is directly calculated by the processing flow shown in FIG.

  Here, the calculation process of the throttle air flow rate QTVO will be described with reference to the flowchart shown in FIG.

  In the throttle air amount calculation flow shown in FIG. 8, first, the voltage value of the air flow sensor (air amount sensor 16) is detected (step S801), the voltage is converted into a flow rate (step S802), and the throttle air flow rate QTVO is obtained. substitute.

Returning to the flowchart of FIG. 5, next, the pressure (intake collector portion estimated pressure) PM of the intake collector 20 is calculated according to the following equation (step S507).
PM = KPM ・ (QTVO + QPRG + QEGR + QREM-QINTV) + PM [Z]
However,
KPM: Intake collector pressure gradient coefficient QTVO: Throttle air flow rate (initial value is 0)
QPRG: Purge air flow rate QEGR: EGR air flow rate QREM: Residual gas air flow rate QINTV: Intake valve air flow rate PM [Z]: Previously calculated value of PM (initial value is atmospheric pressure)

Next, the opening area AEGR of the EGR valve 33 is taken in (step S508), and the EGR air flow rate calculation unit 2055 obtains the EGR air flow rate QEGR flowing through the EGR valve unit according to the following equation (step S509).
QEGR = AEGR, CEGR, KAIRD, CPMEGR, SONIC
However,
AEGR: EGR opening area CEGR: EGR valve part flow coefficient KAIRD: Air density CPMEGR: EGR valve part pressure ratio SONIC: Sound velocity of air

  Here, the EGR valve part pressure ratio CPMEGR is obtained according to the following equation.

但し、
Ｃｐ２：ＥＧＲ部圧力比
ｋ：気体の比熱比

However,
Cp2: EGR part pressure ratio k: Specific heat ratio of gas

The EGR part pressure ratio Cp2 is obtained according to the following equation.
Cp2 = PM / PEXTUB
PM: Intake collector estimated pressure PEXTUB: Exhaust pipe pressure

  Next, the valve overlap (valve OL) opening area AVOL is read (step S510), and the residual gas air flow rate QREM in the cylinder is obtained by the residual gas air flow rate calculation unit 2056 (step S511). The residual gas air flow rate QREM in the cylinder includes the engine speed NDATA, the cylinder pressure PCYL, the valve overlap opening area AVOL obtained from the output signal of the intake valve sensor 48, and the crank position by the crank angle sensor 45. And calculate.

Next, the opening area APRG of the purge valve 38 is taken in (step S512), and the purge air flow rate calculation unit 2059 calculates the purge air flow rate QPRG flowing through the purge valve unit according to the following equation (step S513).
QPRG = APRG, CPRG, KAIRD, CPMPRG, SONIC
However,
APRG: Purge valve opening area CPRG: Purge valve section flow coefficient KAIRD: Air density CPMPRG: Purge valve section pressure ratio SONIC: Speed of sound of air

  Here, the purge valve portion pressure ratio CPMPRG is obtained according to the following equation.

但し、
ＫＣｐ３：パージバルブ部圧力比
ｋ：気体の比熱比

However,
KCp3: Purge valve section pressure ratio k: Gas specific heat ratio

The purge valve portion pressure ratio Cp3 is obtained according to the following equation.
Cp3 = PM / PATM
PM: Intake collector estimated pressure PATM: Atmospheric pressure

Next, based on the cylinder air flow rate QEXTV, EGR air flow rate QEGR, residual gas air flow rate QREM, and purge air flow rate QPRG determined above, the combustion contribution air amount calculation unit 2057 calculates the combustion contribution air amount QCYL according to the following equation. (Step S514).
QCYL = QEXTV-QEGR-QREM-QPRG

Next, the exhaust pipe pressure PEXTUB is obtained by the exhaust pipe pressure calculation unit 2061 according to the following formula (step S515).
PEXTUB = KPEXTUB (QEXTV-QEXTUB [Z] -QEGR-QREM) + PEXTUB [Z]
However,
KPEXTUB: Exhaust pipe pressure gradient coefficient QEXTV: In-cylinder air flow rate QEXTUB [Z]: Last calculated value of exhaust pipe air flow rate QEGR: EGR air flow rate QREM: Residual gas air flow rate PEXTUB [Z]: Last calculated value of PEXTUB

Next, the exhaust pipe air flow rate calculation unit 2058 obtains the exhaust pipe air flow rate QEXTUB according to the following equation (step S516).
QEXTUB = AEXTUB, CEXTUB, KAIRD, CPMEXTUB, SONIC
However,
AEXTUB: Exhaust pipe opening area CEXTUB: Exhaust pipe flow coefficient KAIRD: Air density CPMEXTUB: Exhaust pipe pressure ratio SONIC: Sound velocity of air

  Here, the exhaust pipe pressure ratio CPMEXTUB is obtained according to the following equation.

但し、
Ｃｐ４：排気管部圧力比

However,
Cp4: Exhaust pipe pressure ratio

The exhaust pipe portion Cp4 is obtained according to the following formula.
Cp4 = PATM / PEXTUB
PATM: Atmospheric pressure PEXTUB: Exhaust pipe pressure

  With the above processing flow, the air flow rate and pressure of each part of the series of engine are calculated, and the future combustion contribution air amount (cylinder air amount estimation amount) is predicted by finally repeating this flow as many times as necessary. . In this embodiment, the pressure gradient coefficient and the like are set in advance in the ROM 104 so that the air amount and pressure of each part 40 ms ahead can be obtained by one calculation.

  FIG. 6 shows a control process for controlling the opening degree (opening area) of the throttle valve 18 and the intake valve 25 based on the combustion contribution air amount QCYL calculated in step S514 of the flowchart shown in FIG. This will be described with reference to the flowchart.

  First, a target combustion torque TGTRQ is determined based on an externally requested torque from a device outside the ECU 100 such as an accelerator opening, traction control, cruise control, and transmission (step S601).

  Next, based on the target combustion torque TGTRQ, the target cylinder air amount TGQAR is calculated (step S602), the combustion contributing air amount QCYL is captured (step S603), and the target combustion torque TGTTRQ and the combustion contributing air amount QCYL are compared. (Step S604).

  If the target combustion torque TGTTRQ is larger than the combustion contribution air amount QCYL, the throttle valve 18 and the intake valve 25 are operated so as to increase the engine output torque (step S605). This is air amount increase control, and increases the opening area of the throttle valve 18 and the intake valve 25.

On the other hand, if the target combustion torque TGTRQ is smaller than the combustion contribution air amount QCYL,
If larger, the throttle valve 18 and the intake valve 25 are operated so that the engine output torque decreases. This is air amount reduction control, and the opening areas of the throttle valve 18 and the intake valve 25 are reduced.

  A processing flow of fuel injection and ignition timing calculation will be described with reference to a flowchart shown in FIG.

  First, the combustion contributing air amount QCYL is taken in (step S701). Here, the predicted combustion contribution air amount QCYL80 and the current combustion contribution air amount QCYL 80 ms ahead are taken in for calculation of the fuel injection amount.

  Next, a preset target air-fuel ratio TGABF is taken in (step S702), and a required fuel injection amount TISET is calculated from the target air-fuel ratio TGABF and the predicted combustion contributing air amount QCYL (step S703). A signal of the required fuel injection amount TISET is transmitted from the fuel injection control model unit 206 shown in FIG. 3 to the fuel injection valve control device 53. As a result, fuel is injected from the fuel injection valve 23 with the required fuel injection amount TISET at a predetermined timing.

  Next, the ignition timing FADV is calculated from the combustion contributing air amount QCYL and the engine speed NDATA (step S704). The ignition timing FADV signal is transmitted from the ignition timing control model unit 207 shown in FIG. Thus, a discharge voltage is applied to the spark plug 39 by the ignition coil 40 at a predetermined timing, and the spark plug 39 is ignited at the ignition timing FADV.

  The estimation models by the various estimation model units described above can be corrected according to the measured values of the intake pipe pressure sensor 49 or the air-fuel ratio sensor 41. In the correction of the estimation model, the estimation model is corrected so that the deviation between the intake collector pressure PM calculated from the results of various estimation models and the intake pipe pressure detected by the intake pipe pressure sensor 49 becomes small.

  In the present embodiment, in the internal combustion engine 10 including the intake pipe pressure sensor 49, processes for correcting various estimation models according to the detection result of the intake pipe pressure by the intake pipe pressure sensor 49 are shown in FIGS. This will be described below with reference to the flowchart.

  FIG. 10 shows an example of a processing flow for correcting the estimated intake collector estimated pressure PM in accordance with the detection result of the intake pipe pressure sensor 49.

  First, the voltage value of the intake pipe pressure sensor 49 is taken and converted from the voltage value to the pressure is set as the output PS of the intake pipe pressure sensor 49 (step S1001).

  Next, the estimated intake collector portion estimated pressure PM is taken in (step S1002), and the deviation between the output PS of the intake pipe pressure sensor 49 and the intake collector portion estimated pressure PM is taken, and whether or not this deviation is within a predetermined range. Is determined (step S1003).

  If the deviation does not fall within the predetermined range, the disturbance factor is stopped (step S1004). The disturbance factor stop here is to stop EGR and purge and to set the valve overlap to a predetermined value.

  Next, in the absence of the disturbance, the intake valve opening area AINTV is corrected based on the deviation (step S1005). Accordingly, the intake valve flow rate QINTV is corrected (step S1006). Then, the intake collector estimated pressure PM is updated according to the corrected intake valve flow rate QINTV (step S1007).

  Then, the process returns to step S1002, and the intake collector estimated pressure PM updated in step S1007 is taken in again. In step S1003, the deviation from the output PS of the intake pipe pressure sensor is checked, and step S1002 is continued until the deviation falls within a predetermined range. The flow up to step S1007 is repeated.

  That is, the intake valve opening area AINTV is corrected so that the deviation between the output PS of the intake pipe pressure sensor 49 and the estimated intake collector pressure PM is within a predetermined range in the absence of disturbance such as EGR.

  Accordingly, as shown in FIG. 14, the intake air intake air pressure is calculated so that the deviation between the intake collector estimated pressure PM calculated from the results of various estimation models and the intake air pressure detected by the intake air pressure sensor 49 becomes small. The valve opening area AINTV is modified.

  FIG. 11 shows an example of another processing flow for correcting the estimated intake collector estimated pressure PM in accordance with the detection result of the intake pipe pressure sensor 49. This processing flow is executed when the EGR control is performed after the deviation between the output PS of the intake pipe pressure sensor 49 and the estimated intake collector pressure PM falls within a predetermined range by the processing flow shown in FIG. To do.

  First, the voltage value of the intake pipe pressure sensor 49 is taken and converted from the voltage value to the pressure is set as the output PS of the intake pipe pressure sensor 49 (step S1101).

  Next, the estimated intake collector portion estimated pressure PM is taken in (step S1102), and a deviation between the output PS of the intake pipe pressure sensor 49 and the intake collector portion estimated pressure PM is taken, and whether or not this deviation is within a predetermined range. Is discriminated (step S1103).

  If the deviation does not fall within the predetermined range, the disturbance factor is stopped (step S1104). The disturbance factor stop here is to stop the purge and to set the valve overlap to a predetermined value.

  Next, the EGR valve part air flow rate QEGR is taken in (step S1105), and if the EGR control is being performed (Yes in step S1106), the EGR opening area AEGR is corrected (step S1107). Accordingly, the EGR valve unit air flow rate QEGR is corrected (step S1108). Then, the intake collector portion estimated pressure PM is updated according to the corrected EGR valve portion air flow rate QEGR (step S1109).

  Then, returning to step S1102, the intake collector estimated pressure PM updated in step S1109 is taken in again, and in step S1103, the deviation from the output PS of the intake pipe pressure sensor is checked, and step S1102 is continued until the deviation falls within a predetermined range. The flow up to step S1109 is repeated.

  That is, after the deviation between the intake collector estimated pressure PM and the output PS of the intake pipe pressure sensor is within a predetermined range by correcting the intake valve opening area AINTV, only EGR control is performed, and the intake collector estimated pressure PM When the deviation from the output PS of the intake pipe pressure sensor 49 is not within the predetermined range, the EGR valve opening area AEGR is corrected so that the deviation is within the predetermined range.

  As a result, as shown in FIG. 15, the EGR is such that the deviation between the intake collector estimated pressure PM calculated from the results of various estimation models and the intake pipe pressure detected by the intake pipe pressure sensor 49 becomes small. The valve opening area AEGR is corrected.

  FIG. 12 shows an example of another processing flow for correcting the estimated intake collector estimated pressure PM in accordance with the detection result of the intake pipe pressure sensor 49. In this processing flow, the valve overlap amount is changed after the deviation between the output PS of the intake pipe pressure sensor 49 and the intake collector estimated pressure PM falls within a predetermined range by the processing flow shown in FIG. This is executed when the residual gas flow rate QREM changes.

  First, the voltage value of the intake pipe pressure sensor 49 is taken and converted from the voltage value to the pressure is set as the output PS of the intake pipe pressure sensor 49 (step S1201).

  Next, the estimated intake collector estimated pressure PM is taken in (step S1202), the deviation between the output PS of the intake pipe pressure sensor 49 and the intake collector estimated pressure PM is taken, and whether or not this deviation is within a predetermined range. Is determined (step S1203).

  If the deviation does not fall within the predetermined range, the disturbance factor is stopped (step S1204). The disturbance factor stop here is to stop EGR and purge.

  Next, the valve overlap opening area AVOL is corrected according to the deviation (step S1205). Accordingly, the residual gas flow rate QREM is corrected (step S1206). Then, the intake collector estimated pressure PM is updated according to the corrected residual gas flow rate QREM (step S1207).

  Then, the process returns to step S1202, and the intake collector estimated pressure PM updated in step S1207 is taken in again. In step S1203, the deviation from the output PS of the intake pipe pressure sensor is checked, and step S1202 is continued until the deviation falls within a predetermined range. The flow up to step S1207 is repeated.

  That is, the valve overlap is changed after the deviation between the intake collector estimated pressure PM and the output PS of the intake pipe pressure sensor 49 is within a predetermined range by correcting the intake valve opening area AINTV and the EGR valve opening area AEGR. When the residual gas flow rate QREM changes, if the deviation between the intake collector estimated pressure PM and the intake pipe pressure sensor output PS is not within the predetermined range, the valve is over so that the deviation is within the predetermined range. The lap opening area AVOL is corrected.

  Accordingly, as shown in FIG. 16, the valve is set so that the deviation between the intake collector estimated pressure PM calculated from the results of various estimation models and the intake pipe pressure detected by the intake pipe pressure sensor 49 becomes small. The overlap opening area AVOL is corrected.

FIG. 13 shows an example of another processing flow for correcting the estimated intake collector estimated pressure PM in accordance with the detection result of the intake pipe pressure sensor 49. This processing flow is performed after the deviation between the output PS of the intake pipe pressure sensor 49 and the intake collector estimated pressure PM falls within a predetermined range by the processing flow shown in FIG.
Executed when purge control is performed.

  First, the voltage value of the intake pipe pressure sensor 49 is taken and converted from the voltage value to the pressure is set as the output PS of the intake pipe pressure sensor 49 (step S1301).

  Next, the estimated intake collector portion estimated pressure PM is taken in (step S1302), and a deviation between the output PS of the intake pipe pressure sensor 49 and the intake collector portion estimated pressure PM is obtained, and whether or not this deviation is within a predetermined range. Is determined (step S1303).

  If the deviation does not fall within the predetermined range, the disturbance factor is stopped (step S1304). The disturbance factor stop here is to stop the EGR and set the valve overlap to a predetermined value.

  Next, the purge opening area APRG is corrected (step S1305). Accordingly, the purge air flow rate QPRG is corrected (step S1306). Then, the intake collector estimated pressure PM is updated according to the corrected purge air flow rate QPRG (step S1307).

  Then, the process returns to step S1302, and the intake collector estimated pressure PM updated in step S1307 is taken in again. In step S1303, the deviation from the output PS of the intake pipe pressure sensor is checked, and step S1302 is continued until the deviation falls within a predetermined range. The flow up to step S1307 is repeated.

  That is, the deviation between the intake collector estimated pressure PM and the output PS of the intake pipe pressure sensor 49 is within a predetermined range by correcting the intake valve opening area AINTV and by correcting the EGR valve opening area AEGR and the valve overlap opening area AVOL. Later, when only the purge control is executed and the deviation between the intake collector estimated pressure PM and the output PS of the intake pipe pressure sensor 49 is not within the predetermined range, the purge opening is set so that the deviation is within the predetermined range. Modify area APRG.

  Accordingly, as shown in FIG. 17, the purge is performed so that the deviation between the intake collector estimated pressure PM calculated from the results of various estimation models and the intake pipe pressure detected by the intake pipe pressure sensor 49 becomes small. The opening area APRG is corrected.

  As described above, by correcting the variable (the flow passage area related to intake air) used in the calculation of the various estimated model units described above, the deviation between the pressure PM of the intake collector unit and the pressure of the intake pipe pressure sensor calculated from the results of the various estimated models The estimated model can be modified so that becomes smaller.

  The control operation according to the above-described embodiment (the present invention) and the conventional control operation will be described with reference to the time chart shown in FIG. This time chart shows the intake valve opening area, the intake air amount, the fuel injection amount, the ignition timing, the air-fuel ratio, and the torque indicating the operation results of the variable valve mechanism (VEL) in order from the top, with the horizontal axis as time. Yes.

  In the conventional control, as shown by the solid line in the figure, the air flow sensor detected air amount lags the engine intake air amount with respect to the operation of the intake valve opening area, so both the fuel injection amount and the ignition timing are accurate. Control is impossible. For this reason, fluctuations in the air-fuel ratio occur, resulting in torque fluctuations.

  In the control according to the present invention, the various estimation model sections described so far are used as engine models, and the engine model for simulating the engine operation is mounted on the engine control apparatus 100, and each parameter after a predetermined time is predicted by the engine model. Then, each device is controlled so that the prediction result becomes the target value, and further, the error of the engine model is corrected based on the results of various sensors, and is shown by a dotted line in FIG. As shown, the intake air amount to the engine is accurately estimated in accordance with the operation of the intake valve opening area, and fuel injection and ignition timing control can be performed based on this, thereby eliminating unnecessary air-fuel ratio fluctuations and torque fluctuations. It becomes possible. The above devices are the throttle valve 18, the intake valve 25, the exhaust valve 28, the fuel injection valve 23, and the ignition coil 40.

  As mentioned above, although one Embodiment of this invention was explained in full detail, this invention is not limited to the said embodiment. In the present invention, each component is not limited to the above configuration unless the characteristic functions of the present invention are impaired.

1 is a system configuration diagram showing one embodiment of a fuel injection type internal combustion engine to which a control device according to the present invention is applied. 1 is a block diagram showing an embodiment of a control device for an internal combustion engine according to the present invention. The block diagram which shows one Embodiment of the engine model which the control apparatus of the internal combustion engine by this invention mounts. The block diagram which shows the detail of the cylinder air quantity estimation model part by the control apparatus of the internal combustion engine by this invention. The flowchart which shows the processing flow of the cylinder air quantity estimation model part by the control apparatus of the internal combustion engine by this invention. The flowchart which shows the processing flow of the throttle control model part by the control apparatus of the internal combustion engine by this invention, and an intake valve control model part. The flowchart which shows the processing flow of the fuel-injection control model part by the control apparatus of the internal combustion engine by this invention, and an ignition timing control model part. The flowchart which shows the processing flow of the throttle air flow rate calculation by the throttle air flow rate calculating part by the control apparatus of the internal combustion engine by this invention. The time chart which shows the control operation by this embodiment, and the conventional control operation example. The flowchart which shows the processing flow which corrects an estimation model by correcting the intake valve opening area according to the result of an intake pipe pressure sensor in the control apparatus of the internal combustion engine by this invention. It is a flowchart which shows the processing flow which corrects an estimation model by correcting an EGR opening area according to the result of an intake pipe pressure sensor in the control apparatus of the internal combustion engine by this invention. The flowchart which shows the processing flow which corrects an estimation model by correcting valve overlap opening area according to the result of an intake pipe pressure sensor in the control apparatus of the internal combustion engine by this invention. It is a flowchart which shows the processing flow which corrects an estimation model by correcting a purge opening area according to the result of an intake pipe pressure sensor in the control apparatus of the internal combustion engine by this invention. The time chart which shows the operation example which corrects an estimation model by correcting the intake valve opening area according to the result of an intake pipe pressure sensor. The time chart which shows the operation example which corrects an estimation model by correcting an EGR valve opening area according to the result of an intake pipe pressure sensor. The time chart which shows the operation example which corrects an estimation model by correcting valve overlap opening area according to the result of an intake pipe pressure sensor. The time chart which shows the operation example which corrects an estimation model by correcting the purge opening area according to the result of an intake pipe pressure sensor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Internal combustion engine 11 Engine block 12 Cylinder bore 13 Piston 14 Combustion chamber (cylinder chamber)
DESCRIPTION OF SYMBOLS 15 Air cleaner 16 Air quantity sensor 17 Intake temperature sensor 18 Throttle valve 19 Throttle body 20 Intake collector 20A Intake pipe 21 Throttle sensor 22 Intake branch pipe 23 Fuel injection valve 24 Intake port 25 Intake valve 26 Intake variable valve mechanism 27 Exhaust port 28 Exhaust valve 29 Exhaust variable valve mechanism 30 Catalytic converter 31 Exhaust pipe 32 Exhaust gas recirculation passage 33 EGR valve 34 Fuel tank 35 Fuel pump 36 Canister 37 Purge passage 38 Purge valve 39 Spark plug 40 Ignition coil 41 Air-fuel ratio sensor 42 Oxygen sensor 43 Connecting rod 44 Crankshaft 45 Crank angle sensor 46 Water temperature sensor 47 Pressure regulator 48 Intake valve sensor 49 Intake pipe pressure sensor 51 Throttle control Control device 52 Intake valve control device 53 Fuel injection control device 54 Ignition timing control device 100 Engine control device (ECU)
101 Input Circuit 102 A / D Converter 103 CPU
104 ROM
105 RAM
DESCRIPTION OF SYMBOLS 106 Output circuit 201 Throttle passage air amount estimation model part 202 Intake valve passage air amount estimation model part 203 In-cylinder intake pressure estimation model part 204 Cylinder residual gas estimation model part 205 Cylinder air amount estimation model part 206 Fuel injection control model part 207 Ignition timing control model unit 208 Target cylinder air amount calculation model unit 209 Throttle control model unit 210 Intake valve control model unit 2051 In-cylinder air flow rate calculation unit 2052 Intake valve air flow rate calculation unit 2053 Slot air flow rate calculation unit 2054 Intake collector unit Estimated pressure calculation unit 2055 EGR air flow rate calculation unit 2056 Residual gas air flow rate calculation unit 2057 Combustion contribution air amount calculation unit 2058 Exhaust pipe air flow rate calculation unit 2059 Purge air flow rate calculation unit

Claims (4)

A throttle control device that controls the amount of air to the internal combustion engine by means of a throttle valve, an intake valve control device that operates the intake valve to a predetermined position, an intake valve sensor that detects the operating state of the intake valve, and an intake pipe pressure A control device for an internal combustion engine having an intake pipe pressure sensor for detecting , a fuel injection device for supplying fuel, and an ignition device for performing ignition,
An intake valve passage air amount estimation model unit that estimates an intake valve passage air amount according to the output of the intake valve sensor;
An in-cylinder intake pressure estimation model unit that estimates an in-cylinder intake pressure according to the intake valve passage air amount estimated by the intake valve passage air amount estimation model unit;
A cylinder residual gas estimation model unit that estimates a cylinder residual gas amount according to the output of the intake valve sensor;
Cylinder air amount estimation model for estimating the cylinder air amount according to the cylinder intake pressure estimated by the cylinder intake pressure estimation model unit and the cylinder residual gas amount estimated by the cylinder residual gas estimation model unit And
A target cylinder air amount calculation model unit that calculates a target cylinder air amount based on the target combustion torque ,
Controlling at least one of fuel injection by the fuel injection device and ignition timing by the ignition device based on the cylinder air amount estimated by the cylinder air amount estimation model unit ;
The throttle control device and the intake air so as to reduce the difference between the target cylinder air amount calculated by the target cylinder air amount calculation model unit and the cylinder air amount estimated by the cylinder air amount estimation model unit. Operate the valve control device,
Correcting each estimated model so that a deviation between the pressure of the intake collector calculated from the result of the estimated model by each estimated model and the intake pipe pressure detected by the intake pipe pressure sensor is reduced. A control device for an internal combustion engine.   A purge air flow rate calculation unit that calculates a purge air flow rate by a purge device that purges the evaporated gas of the fuel tank into the engine intake system, and the amount of air in the cylinder is determined by the purge air flow rate calculated by the purge air flow rate calculation unit The control apparatus for an internal combustion engine according to claim 1, wherein the cylinder air amount estimated by the estimation model unit is corrected as a combustion contributing air amount.   An EGR air flow rate calculation unit for calculating an EGR air flow rate by the exhaust gas recirculation device, and the cylinder air amount estimated by the cylinder air amount estimation model unit by the EGR air flow rate calculated by the EGR air flow rate calculation unit; The control device for an internal combustion engine according to claim 1 or 2, wherein the air amount is corrected as a combustion-contributing air amount. An intake valve control device that operates the intake valve to a predetermined position; an intake valve sensor that detects an operating state of the intake valve; an intake pipe pressure sensor that detects an intake pipe pressure ; a fuel injection device that supplies fuel; An internal combustion engine control device having an ignition device for performing ignition,
An intake valve air flow rate calculating means for calculating an intake valve passing air amount according to an output of the intake valve sensor;
In-cylinder intake pressure calculation means for calculating the intake pressure in the cylinder according to the intake valve air flow rate calculated by the intake valve air flow rate calculation unit;
An in-cylinder air flow rate calculating means for calculating an in-cylinder air flow rate according to the in-cylinder intake pressure calculated by the in-cylinder intake pressure calculating unit;
A purge air flow rate calculating means for calculating a purge air flow rate by a purge device for purging the evaporation gas of the fuel tank to the engine intake system;
EGR air flow rate calculation means for calculating an EGR air flow rate by the exhaust gas recirculation device;
In-cylinder residual gas flow rate calculating means for calculating a residual gas flow rate in the cylinder due to valve overlap according to the output of the intake valve sensor;
The cylinder air flow rate calculated by the cylinder air flow rate calculation means, the purge air flow rate calculated by the purge air flow rate calculation means, the EGR air flow rate calculated by the EGR air calculation means, and the cylinder residual gas flow rate calculation means A combustion contribution air amount calculation means for calculating a combustion contribution air amount from the residual gas flow rate in the cylinder calculated by
An intake collector section pressure estimation calculation means for estimating the pressure of the intake collector section ,
It said combustion contributes to control at least one of ignition timing by the ignition device and fuel injection by the fuel injection device based on the combustion contribution air amount calculated by the air amount calculation means,
Intake valve air flow by the intake valve air flow rate calculation means is reduced so that a deviation between the intake collector pressure estimated by the intake collector pressure estimation calculation means and the intake pipe pressure detected by the intake pipe pressure sensor is reduced. Intake valve opening area used for calculating the flow rate, EGR valve opening area used for calculating the EGR air flow rate by the EGR air flow rate calculating unit, and valve used for calculating the residual gas flow rate in the cylinder by the residual gas flow rate calculating means in the cylinder A control apparatus for an internal combustion engine, wherein at least one of an overlap opening area and a purge opening area used for calculating a purge air flow rate by the purge air flow rate calculating means is corrected .

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