JP4185079B2 - Control device for internal combustion engine - Google Patents

Description

  The present invention relates to an internal combustion engine control device including an intake air amount control means for controlling an intake air amount to an internal combustion engine, and the in-cylinder pressure at the time when the intake valve of the cylinder is fully closed and the intake air sucked into the cylinder The present invention relates to a control device for an internal combustion engine that estimates an air amount before starting fuel injection.

As a method of calculating the amount of intake air into the cylinder of an internal combustion engine, it is conventionally known to install a pressure sensor, an air flow sensor, etc. and calculate the amount of intake air from the detected value.
In this case, there is a cost due to the provision of sensors. In particular, in a multiple throttle system in which a throttle is installed for each cylinder, sensors are also installed for each cylinder, resulting in higher costs.
Therefore, for example, Japanese Patent Application Laid-Open No. 5-222998 (hereinafter referred to as Patent Document 1) estimates the amount of intake air into the cylinder without using a pressure sensor or an airflow sensor, and implements fuel amount control. An intake state detection device for an internal combustion engine as shown in FIG.
In this publication, the throttle valve, the intake valve, and the exhaust valve are regarded as orifices, and the orifice portion is determined based on the fluid dynamics equation based on the flow area of the orifice and the pressure upstream and downstream of the orifice. Estimate the amount of air passing through (orifice passage flow rate). A new throttle downstream pressure is estimated from the estimated throttle portion passage flow rate and intake valve passage flow rate, and a new in-cylinder pressure is estimated from the intake valve passage flow rate and the exhaust valve passage flow rate, and is used for each next passage flow rate estimation. By performing this sequentially according to the crank angle, the throttle downstream pressure, the in-cylinder pressure, and the intake air amount by integrating the intake inflow / outflow amount into the cylinder are estimated. Thus, it is described that the fuel amount control can be performed by estimating the amount of intake air into the cylinder without using a pressure sensor, an air flow sensor, or the like.

JP-A-5-222998

In general, the timing of starting fuel injection in the cylinder of the internal combustion engine is about two strokes with respect to the time when the intake valve of the cylinder is completely closed in consideration of the suction time to the cylinder and the time required for atomization of the fuel. This has been set before, and this indicates that it is necessary to estimate the amount of intake air into the cylinder approximately two strokes ahead of the timing at which fuel injection of the cylinder starts.
However, in the above prior art, the throttle downstream pressure, in-cylinder pressure, and intake inflow / outflow amount in the cylinder are estimated in real time according to the crank angle, so the intake air amount used for fuel injection control is For example, the intake air amount of another cylinder that has completed the intake stroke must be used two strokes before the cylinder completes the intake stroke.

The control will be described with reference to FIG.
FIG. 1 shows a stroke table (horizontal axis: time, vertical axis: cylinder number) of each cylinder in a 4-cylinder engine. Symbols and the like in FIG. 1 are as shown in the legend on the right side of FIG.
The control will be described by taking the fuel injection timing α of the fourth cylinder as an example.
Since the fuel injected at the fuel injection timing α of the fourth cylinder is sucked into the cylinder during the intake stroke β of the fourth cylinder, fuel control is performed based on the intake air amount during the intake stroke β of the fourth cylinder. Is desirable. However, as can be seen from FIG. 1, since the fuel injection timing α of the fourth cylinder comes before the intake stroke β of the fourth cylinder, the intake stroke β of the fourth cylinder is based on the fuel injection timing α of the fourth cylinder. The fuel cannot be controlled. Therefore, in the prior art, the fuel control is performed at the fuel injection timing α of the fourth cylinder based on the intake air amount estimated by the intake stroke γ of the first cylinder.

In this case, especially if the throttle flow path area changes abruptly during transient operation, as shown in FIG. 2, the difference between the actual intake air amount and the intake air amount used in the fuel amount calculation increases. Exhaust gas, fuel consumption, drivability, etc. will be adversely affected.
Further, in the above prior art, when estimating the downstream pressure of the throttle, the in-cylinder pressure, and the intake inflow / outflow amount to the in-cylinder, the passage flow rate is estimated at a total of three locations of the throttle valve, the intake valve, and the exhaust valve. The calculation load to be implemented is large. If the internal combustion engine speed increases, the allowable calculation time for estimating the flow rate through each part will decrease, so if the calculation load is large, the estimation will not be in time, and it is necessary to install a more sophisticated control unit to avoid it. Occurs. This causes a problem that the cost is increased.

  The present invention has been made to solve the above-described problems of the conventional apparatus. In addition to estimating the real-time throttle downstream pressure, in-cylinder pressure, and intake air amount according to the crank angle, the present invention provides By estimating the downstream pressure of the throttle, the in-cylinder pressure, and the intake air amount when the intake valve of the cylinder is fully closed prior to the crank angle by the time when fuel injection is started, the estimated intake air to the cylinder is estimated. An object of the present invention is to provide a control device for an internal combustion engine that can perform high-precision fuel injection control using the amount.

  Also, instead of estimating the passage flow rate of the throttle part, intake valve and exhaust valve in total, only the throttle passage flow rate is estimated and the throttle downstream pressure, in-cylinder pressure and intake air amount are estimated, It is an object of the present invention to provide a control device for an internal combustion engine that can reduce the calculation load.

The control device for an internal combustion engine according to the present invention includes a cylinder connected to each of the independent intake pipes, one end of which is connected to the intake valve of each cylinder of the internal combustion engine having a plurality of cylinders, and the other end is connected to a collecting portion of each cylinder. An intake air amount control means for controlling the intake air amount to the engine and a port injection type internal combustion engine control device that performs exhaust stroke injection is a model of the intake passage from the intake air amount control means upstream to the intake valve Intake air valve closed model, intake valve open model that models the intake passage from upstream of intake air amount control means to the cylinder in consideration of volume change, intake air amount estimation model, and intake air amount control means A flow passage area detecting means for detecting the flow passage area, a downstream pressure detecting means for detecting a pressure downstream of the intake air amount control means, and an internal combustion engine speed detecting means, and the two intake air amount estimation models, intake air amount control The upstream pressure and the downstream pressure of the step, the flow passage area of the intake air amount control means, by using the engine speed, the cylinder volume, the intake air temperature, fuel this injection is sucked into the cylinder Thereafter, the in-cylinder pressure and the intake air amount sucked into the cylinder at the time when the intake valve of the cylinder is completely closed are estimated by the time when the current fuel injection is started .

  According to the control device for an internal combustion engine of the present invention, the intake air amount at the time when the intake valve of the cylinder is fully closed can be estimated prior to the crank angle by the time when the fuel injection of the cylinder is started. Based on the quantity, it is possible to carry out highly accurate fuel injection control, particularly during transient operation of the internal combustion engine.

  Also, use a calculation model that estimates the intake air amount by estimating only the flow rate through the throttle section, instead of estimating the flow rate at the three locations of the throttle section, intake valve, and exhaust valve as in the prior art. Thus, the calculation load for estimating the intake air amount is reduced, and the intake air amount can be estimated with a low-cost arithmetic device.

In the present invention, as in the prior art, control for estimating the throttle downstream pressure, the cylinder pressure, and the intake air amount in real time for each predetermined period according to the crank angle based on the fluid dynamic equation (hereinafter referred to as real time estimation control). Control that predicts the throttle downstream pressure, in-cylinder pressure, and intake air amount when the intake valve is fully closed by the time the fuel injection starts before the crank angle (hereinafter, prediction estimation) Also called control).
The throttle downstream pressure at an arbitrary crank angle in the real-time estimation control and the prediction estimation control is estimated by a recurrence formula such as Formula 1 below, for example.

That is, the throttle downstream pressure at an arbitrary crank angle CA-ΔCA is a basis for estimating the throttle downstream pressure at CA.
Predictive estimation control immediately estimates the throttle downstream pressure, the in-cylinder pressure, and the intake air amount when the intake valve is fully closed from a predetermined time (hereinafter referred to as a predetermined time A) before the fuel injection start time. For this purpose, a recurrence formula such as Formula 1 based on a fluid dynamic formula from the throttle upstream pressure and downstream pressure, the throttle flow path area, the cylinder volume, the internal combustion engine speed, and the intake air temperature is used as the crank angle. By repeating the process until the intake valve is fully closed for the first time, the estimation of the throttle downstream pressure, the in-cylinder pressure, and the intake air amount when the intake valve is fully closed is completed.
Hereinafter, for convenience, the throttle downstream pressure and the in-cylinder pressure in the predictive estimation control will be referred to as the predicted estimated downstream pressure and the predicted estimated in-cylinder pressure, respectively, and the predicted estimated downstream pressure and the predicted estimated cylinder when the intake valve is fully closed. The internal pressure is referred to as fuel control downstream pressure and fuel control cylinder pressure. The intake air amount estimated from the in-cylinder pressure when the fuel control cylinder pressure and the intake valve are fully closed and the intake air temperature is referred to as the fuel control intake air amount. Further, the throttle downstream pressure and the in-cylinder pressure in the real-time estimation control are referred to as an estimated downstream pressure and an estimated in-cylinder pressure, respectively.

FIG. 3 shows an image of the relationship between the actual throttle downstream pressure, the estimated downstream pressure, and the predicted estimated downstream pressure.
FIG. 3 assumes a multiple throttle system. The upper diagram shows the relationship between the crank angle and the actual throttle downstream pressure, the middle diagram shows the relationship between the crank angle and the estimated downstream pressure and the estimated estimated downstream pressure in the N cycle, and the lower diagram. Shows the relationship between the crank angle and the estimated downstream pressure in the N + 1 cycle.
As shown in FIG. 3, the estimated downstream pressure is estimated for each predetermined period by the real-time estimation control, while the fuel control downstream pressure is estimated by the prediction estimation control from the predetermined time A to the time when fuel injection is started.
The throttle downstream pressure at the predetermined time A is required to start the predictive estimation control. This is estimated by the real time estimation control as shown in FIG. 3, or the pressure sensor is installed in the throttle downstream portion of each cylinder. The throttle downstream pressure value acquired from the pressure sensor or the like when the crank angle reaches the predetermined timing A of the cylinder is used.
In the prior art, the flow downstream of the throttle valve, the intake valve, and the exhaust valve is estimated to estimate the downstream pressure of the throttle, the in-cylinder pressure, the intake air amount, and the like. The calculation load is reduced by estimating only the partial passage flow rate and estimating the throttle downstream pressure, cylinder pressure, intake air amount, and the like.

Specifically, in a multiple throttle system, an intake valve closed model that models the intake passage from the throttle upstream to the intake valve, and an intake valve open that models the intake passage from the upstream of the throttle to the cylinder in consideration of volume changes. Two intake air quantity estimation models are used.
The intake valve closed model is used to estimate the throttle downstream pressure, the cylinder pressure, the intake air amount, etc. when the intake valve is closed, and the intake valve open model when the intake valve is open.
In a general collective throttle system that controls the intake air amount of an internal combustion engine by installing a throttle in a passage where the intake pipes of the cylinders gather, the intake air from the upstream side of the throttle to each cylinder taking into account the volume change A collective throttle system model that models the passage is used.
In addition, by acquiring the downstream pressure for fuel control, the in-cylinder pressure for fuel control, the atmospheric pressure and intake air temperature used when estimating the intake air amount for fuel control, etc. from the sensor, and using those values, higher accuracy is achieved. The fuel control downstream pressure, the fuel control cylinder pressure, and the fuel control intake air amount can be estimated.
Hereinafter, it demonstrates in detail based on embodiment.

Embodiment 1 FIG.
Embodiment 1 of the present invention is an example of application of the present invention in a multiple throttle system in which a throttle is installed for each cylinder. In the first embodiment, estimation of the estimated downstream pressure at a predetermined time A by real-time estimation control and estimation of the intake air amount for fuel control by prediction estimation control based on the estimated downstream pressure at the predetermined time A are performed.
In the first embodiment, in the estimation of the estimated downstream pressure and the intake air amount for fuel control, the intake valve closed model that models the intake passage from the upstream of the throttle to the intake valve, and the in-cylinder that takes into account the volume change from the upstream of the throttle The intake valve open model that models the intake passage up to is used.
The intake valve closed model and intake valve open model are the throttle upstream flow rate, downstream pressure, cylinder pressure, throttle channel area, cylinder volume, internal combustion engine speed, and intake air temperature based on the fluid dynamics formula. And a calculation for estimating new throttle downstream pressure and in-cylinder pressure from the estimated throttle passage flow rate and in-cylinder volume change is performed.
That is, the calculation load is reduced by calculating the passage flow rate of only the throttle part, instead of calculating the passage flow rate of the throttle part, the intake valve part, and the exhaust valve part as in the prior art.

Hereinafter, the first embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 4 is a schematic diagram showing an example of the overall configuration of the control apparatus for an internal combustion engine according to the first embodiment of the present invention. FIG. 4 shows a multiple throttle system, where only the first cylinder is shown as a representative, but the second to fourth cylinders of the engine are similarly configured.
In FIG. 4, the engine is provided with a throttle valve 1, a fuel injection valve 2, an intake valve 3, an exhaust valve 4, and a crank angle sensor 5 in the engine body for limiting the intake amount for each cylinder.
The throttle valve 1 is driven by a throttle actuator 6 installed for each throttle valve 1, and the throttle valve 1 is electronically controlled by sending a throttle opening control signal to the throttle actuator 6 by the throttle control unit 7.
The throttle actuator 6 is provided with a sensor (hereinafter referred to as TPS) for detecting the throttle opening, and transmits a throttle opening detection signal to the throttle control unit 7. In the first embodiment, the throttle control unit 7 is provided for each throttle actuator 6 and each throttle valve 1 is controlled individually.

A throttle opening detection signal is input from the throttle actuator 6 to the throttle control unit 7, and an engine speed signal, a crank angle signal, and a target intake air amount signal are input from the engine control unit 8. A throttle opening control signal is output from the throttle control unit 7 to the throttle actuator 6, and a fuel control intake air amount signal is output to the engine control unit 8.
In the throttle control unit 7, the target throttle opening is determined from the throttle opening detection signal, the fuel control intake air amount and the target intake air amount signal, and the fuel control intake air amount is determined from the engine speed signal and the crank angle signal. The estimation process is performed.
In FIG. 4, the throttle downstream pressure is the pressure in the throttle downstream portion 9, and the in-cylinder pressure is the pressure in the cylinder 10.

The engine control unit 8 receives an accelerator depression amount detection signal from the accelerator position sensor and a crank angle detection signal from the crank angle sensor 5.
Then, a fuel injection control signal is output from the engine control unit 8 to the fuel injection valve 2 of each cylinder. The fuel injection valve 2 is injected independently for each cylinder.
The engine control unit 8 detects the engine speed and crank angle from the crank angle detection signal, determines the target intake air amount from the accelerator depression amount and the intake air amount for fuel control, the intake air amount for fuel control and the target air-fuel ratio, etc. From this, the fuel injection amount is determined.

By the way, in the prior art, the flow downstream of the throttle valve, the intake valve, and the exhaust valve is estimated to estimate the throttle downstream pressure, the in-cylinder pressure, the intake air amount, and the like. In order to achieve a reduction in the calculation load by estimating only the throttle flow rate and estimating the throttle downstream pressure, cylinder pressure, intake air amount, etc., in the multiple throttle system, from the throttle upstream to the intake valve The intake valve closed model (Fig. 5), which models the intake passage of the engine, and the intake valve open model (Fig. 6), which models the intake passage from the upstream of the throttle to the cylinder in consideration of volume change The estimated model is used by judging the state of the intake valve.
Therefore, the intake valve closing model and the intake valve opening model used in Embodiment 1 will be described with reference to FIGS.

In FIG. 5, the intake valve closed model is a model for estimating the throttle passage flow rate and the throttle downstream pressure, the intake air amount, etc. when the intake valve is closed. It is formed from the throttle downstream part from the throttle part to the intake valve, and the inside of the cylinder is not considered.
Throttle upstream section is composed of the throttle upstream pressure P ₁ and the intake air temperature T _1.
The throttle opening is composed of a throttle flow path area _AT, and the intake air passing through the throttle opening receives pressure from the throttle upstream pressure P ₁ and the throttle downstream pressure P ₂ .
Throttle downstream portion is configured as a throttle downstream pressure P ₂ and the throttle downstream volume V ₂ from the intake air temperature T _1.
Note throttle upstream pressure P ₁ is handled as a substantially atmospheric pressure, intake air temperature T ₁ of the treated as constant across.
The estimation of the flow rate through the throttle in the intake valve closed model in FIG. 5 is estimated from the following equation based on the fluid dynamic equation.

Equations (2) and (3) are divided into cases based on the pressure ratio between the upstream and downstream of the throttle, which is an index as to whether or not the speed of the intake air passing through the throttle becomes the speed of sound. Equation (3) when the velocity of the passing intake air is less than the sonic velocity is the throttle passage flow rate per unit time when the sonic velocity is satisfied.
From the throttle flow rate per unit time, the predetermined period, the throttle downstream pressure P ₂ , the throttle downstream volume V _2, and the intake air temperature T ₁ , the throttle downstream pressure after the predetermined period is calculated using the gas state equation. presume. The estimated throttle downstream pressure is further used as a basis for estimating the throttle downstream pressure after a predetermined period. The above processing is performed at predetermined intervals, and when the intake valve starts to open, the intake valve opening model is switched.

The intake valve opening model in FIG. 6 is a model for estimating the throttle passage flow rate and the throttle downstream pressure, in-cylinder pressure, intake air amount and the like when the intake valve is open. An opening, a throttle downstream part from the throttle part to the intake valve, and a cylinder whose volume changes according to the crank angle are formed.
The throttle upstream portion, the throttle opening portion, and the throttle downstream portion have the same configuration as that of the throttle intake valve closed model, and the intake air temperature is also constant throughout the entire area.
Cylinder is composed with in-cylinder pressure P ₃ and the cylinder volume V ₃ from the intake air temperature T _1, cylinder volume V ₃ changes according to crank angle. It is assumed that the in-cylinder pressure P ₃ is in equilibrium with the throttle downstream pressure (P ₂₃ (P ₂ = P ₃ )) except when the intake valve starts to open.
When estimating the throttle passage flow rate at the time when the intake valve starts to open, it is first necessary to estimate the pressure when the throttle downstream pressure and the cylinder pressure at the time when the intake valve starts to open are balanced.
The reason for this is that the exhaust stroke is just before the intake valve opens, so the cylinder is at approximately atmospheric pressure. When the intake valve is opened in this state, the cylinder downstream at approximately atmospheric pressure communicates with the throttle downstream that is at negative pressure. This is because the downstream pressure and the in-cylinder pressure are in an equilibrium state. The throttle downstream pressure and the in-cylinder pressure after pressure equilibrium are estimated from the following equations based on the gas equation of state.

Since the in-cylinder pressure when the intake valve begins to open is approximately atmospheric pressure, P ₃ -IVO
The value to be equal to the upstream intake air pressure P _1.
In addition, when estimating the flow rate through the throttle with the intake valve open model, the difference between the intake valve close model and the intake valve closed model is that the throttle downstream pressure and in-cylinder pressure change due to changes in the in-cylinder volume. It is necessary. Therefore, when estimating the flow rate through the throttle, the throttle downstream pressure and the in-cylinder pressure when the in-cylinder volume changes are estimated based on the assumption that there is no flow rate from the throttle during a predetermined period (the following formula ( 5)), and the throttle flow rate is estimated based on the estimated throttle downstream pressure and in-cylinder pressure (the following equations (6) and (7)).

The above formulas (6) and (7) are the same as the above formulas (1) and (2). Incidentally, after estimating the P ₂₃ _ _IVO by formula (4) at the time the intake valve starts to open, to it the equation (5) in the P _{23_Old} per unit time passing through the throttle flow rate estimation as.
And per unit time passing through the throttle flow rate of the, and the predetermined period, the present time and the throttle downstream pressure and the in-cylinder pressure _P '23_old of (assuming that there is no flow from the throttle), the cylinder contents throttle downstream volume V ₂ and the current From the sum of the products V 3 — _new and the intake air temperature T ₁ , the current throttle downstream pressure and in-cylinder pressure are estimated using the gas equation of state. The estimated throttle downstream pressure and in-cylinder pressure are further used as a basis for estimating the throttle downstream pressure and the in-cylinder pressure after a predetermined period.
Carry out the above processing at predetermined intervals and estimate the amount of intake air into the cylinder from the cylinder pressure, cylinder volume, and intake air temperature using the gas equation of state when the intake valve reaches the point where it closes. rear,
Switch to intake valve closed model.

Next, an intake air amount estimation flow 1 performed by the throttle control unit 7 will be described. 7 to 14 show flowcharts of the intake air estimation flow 1. FIG.
In the intake air amount estimation flow 1, as described above, the intake valve closing model and the intake valve opening model of FIGS. 5 and 6 are used.
Further, the throttle control unit 7 is connected to the throttle valve upstream pressure P ₁ (= constant), the intake air temperature T ₁ (= constant) value, and the valve timing map of the intake valve using the crank angle as parameters (FIG. 15: Judgment of intake valve opening / closing) Use).
The intake air amount estimation flow 1 is performed when a trigger sent from the engine control unit 8 to the throttle control unit 7 is received every predetermined cycle ΔCA based on the crank angle, and the predicted estimated downstream pressure and predicted estimated cylinder are determined by the predicted estimation control. Estimated downstream pressure and estimated in-cylinder pressure are estimated by internal pressure, intake air amount for fuel control, and real-time estimation control.

The intake air amount estimation flow 1 includes control logic (FIGS. 12 to 14) for performing predictive estimation control, and control logic (steps s1, s2, and s4 to s20 for executing real-time estimation control (FIGS. 7 and 8). )).
In the prediction estimation control and the real-time estimation control, the predicted estimated downstream pressure, the intake air amount for fuel control, and the like are calculated using the above equations (2) to (7) and the gas state equation.
In the intake air amount estimation flow 1, from before ΔCA to the present time, based on the throttle passage flow rate per unit time and the gas state equation shown in the above equations (2), (3), (6), (7) The throttle downstream pressure that changes depending on the throttle passage flow is calculated from the following equation.

  Further, as explained in the above equation (4), when estimating the throttle passage flow rate at the time when the intake valve starts to open, first, the pressure when the throttle downstream pressure and the in-cylinder pressure at the time when the intake valve starts to open is estimated. There is a need to. In the intake air amount estimation flow 1, the pressure at equilibrium is calculated from the following formula based on the formula (4).

Furthermore, as shown in equation (5), when calculating the throttle downstream pressure and in-cylinder pressure in the intake valve opening model, the in-cylinder volume changes on the assumption that there is no flow rate from the throttle between ΔCA. After that, it is necessary to calculate the throttle downstream pressure and the cylinder pressure.
In the intake air amount calculation flow 1, the downstream pressure of the throttle and the in-cylinder pressure after the in-cylinder volume is changed are calculated by the following equation (10).

The above formulas (8) to (10) are replaced with the intake valve closed model (only formula (8)) and the intake valve open model (formulas (8) and (10), and formula (9) when the intake valve starts to open). The cylinder downstream pressure and the in-cylinder pressure when the intake valve is open are estimated or predicted for proper use.
The estimated amount of intake air sucked into the cylinder when the intake valve is fully closed using the gas equation of state from the cylinder pressure, cylinder volume and intake air temperature estimated by predictive estimation I can do it.
Hereinafter, each step will be described. In the intake air amount calculation flow 1, it is assumed that the current crank angle in equations (8) to (10) is CA1, the calculation cycle is ΔCA1, and values are substituted into CA1 and ΔCA1.

First, in step s1, it is confirmed whether the engine is operating. If it is operating, the process proceeds to step s2. If it is stopped, the process proceeds to step s3.
When the engine is stopped, the intake flow rate is accumulated in the throttle downstream volume via the throttle, so that the throttle downstream pressure is recovered to the atmospheric pressure. Therefore, in step s3, since the throttle upstream pressure is substantially atmospheric pressure (P _{2_old} = P ₁ ), the intake air amount calculation flow 1 is terminated and the process waits until the next trigger is received.

When the process proceeds from the s1 step to the s2 step, the engine control unit 8 reads the crank angle, the engine speed, and the throttle opening from the throttle actuator 6, and the process proceeds to the s4 step.
In step s4, it is determined whether or not the intake valve is closed at the present time (crank angle CA) by referring to the valve timing map (FIG. 15) of the intake valve (hereinafter, the time when the intake valve starts to open is IVO, The time when the intake valve is fully closed is called IVC).
If the intake valve is closed, the process proceeds to step s5, and if the intake valve is open, the process proceeds to step s12 (FIG. 8).

When the process proceeds to step s5, it is determined whether the intake valve is closed in the previous cycle (= CA−ΔCA) in the same manner as in step s4.
If closed, go to step s6, and if open, go to step s8.

When the process proceeds to step s6, the estimated downstream pressure is calculated by real-time estimation control using the intake valve closing model up to step s7.
First, in step s6, ΔCA1 = ΔCA and CA1 = CA are carried out, and the process proceeds to step s7.
In step s7, intake valve closing model calculation is performed. The intake valve closing model calculation is composed of steps s23 to 28 as shown in FIG.
First, in step s23, the time term S is calculated from the engine speed and ΔCA1. Then, conduct the volume term V = _{V 2} in s24 step, proceed to s25 step.
In step s25, the speed term H is calculated from (P _{2_old} / P ₁ ) and the speed term map. In step s26, the area term D is calculated from the throttle opening and the area term map, and the process proceeds to step s27.
In step s27, the estimated downstream pressure at CA1 is calculated from equation (8).
Thereafter, P _{2_old} = P _{2_new} is performed in step _s28, and the process proceeds to step s21.

If the intake valve is open in the previous cycle (= CA-ΔCA) and the intake valve is closed at the current time (= CA), that is, if the s5 step is advanced from the s5 step, the intake valve open model is first made up to the s9 step. Used to calculate the estimated downstream pressure and estimated in-cylinder pressure at IVC by real-time estimation control. Then, the estimated downstream pressure after IVC is calculated by real-time estimation control from step s10 to step s11 to step s7.
In step s8, ΔCA1 = IVC− (CA−ΔCA) and CA1 = IVC are performed to calculate the estimated downstream pressure and estimated in-cylinder pressure in IVC, and the process proceeds to step s9.

In step s9, intake valve opening model calculation is performed. As shown in FIG. 11, the intake valve opening model calculation includes s29 to 37 steps.
First, in step s29, a time term S is calculated from the engine speed and ΔCA1.
Thereafter, in step s30, the in-cylinder volume _{V3_new} at CA1 is calculated from CA1 and the in-cylinder volume map, and the volume term V is calculated.
In step s31, the estimated downstream pressure and the estimated in-cylinder pressure at CA1 (assuming that there is no flow rate from the throttle) in the intake valve opening model are calculated using equation (10).
In s32 step, implementing the _{P 2_old} = _{P 2_new,} in s33 step calculates _{(P 2_old} / _{P 1)} and calculate the velocity term H from speed terms map, the area term D from the throttle opening degree and an area section map in s34 step The process proceeds to step s35.
In step s35, the estimated downstream pressure and estimated in-cylinder pressure at CA1 are calculated from equation (8).
Thereafter, P3_old _{= P3_new} is implemented in step s36, _{P2_old = P2_new} is implemented in step s37, and the process proceeds to step s10.

In step s10, the predetermined time A is calculated. This is calculated from the engine speed and a predetermined time A map (FIG. 19: a map using the engine speed as a parameter).
As can be seen from FIG. 19, the predetermined time A is shifted by a predetermined period ΔCA toward the start of the predictive estimation control earlier in order to secure the estimated processing time as the engine speed increases. After calculating the predetermined time A, the process proceeds to step s11.
In step s11, ΔCA1 = CA−IVC and CA1 = CA are performed to prepare for the calculation of the estimated downstream pressure after IVC. Thereafter, the intake valve closing model calculation is performed in step s7 to calculate the estimated downstream pressure in CA1, and the process proceeds to step s21.

When the intake valve is open at the present time (= CA), that is, when the process proceeds from step s4 to step s12, whether or not the intake valve has already been opened in the previous cycle (= CA−ΔCA) in step s12. Determine. If it is open, the process proceeds to step s13, and if it is closed, the process proceeds to step s15.
When proceeding to step s13, ΔCA1 = ΔCA and CA1 = CA are performed, and in step s14, the intake valve opening model calculation described in step s9 is performed to calculate the estimated downstream pressure and the estimated in-cylinder pressure in CA1. Then, the process proceeds to step s21.

When the intake valve is closed in the previous cycle (= CA−ΔCA) and the intake valve is open at the present time (= CA), that is, when the process proceeds from step s12 to step s15, the estimated downstream pressure at IVO until step s16 Is calculated. Then, the estimated downstream pressure after IVO and the estimated in-cylinder pressure are calculated through steps s17 to s20 and up to step s14.
First, ΔCA1 = IVO− (CA−ΔCA) and CA1 = IVO are performed in order to calculate the estimated downstream pressure at IVO in step s15, and the process proceeds to step s16.
In step s16, the intake valve closing model calculation described in step s7 is performed to calculate the estimated downstream pressure at IVO.
In step s17, the in-cylinder volume _{V3_new} at IVO is calculated from the IVO and in-cylinder volume map.
In step s18, the pressure when the throttle downstream pressure and the cylinder pressure at IVO are balanced is estimated. This is calculated from Equation 9.
After that, _{P2_old = P2_new} is executed in step _s19 , _{ΔCA1 = ΔCA} and CA1 = CA are executed in step s20, and the intake valve opening model calculation is executed in step s14 to estimate the estimated downstream pressure in CA1. And the estimated in-cylinder pressure is calculated. Thereafter, the process proceeds to step s21.

From step s21 onward, predictive estimation control is performed.
First, in step s21, it is determined whether or not the predictive estimation control is to be performed by determining whether or not CA is the predetermined time A.
If CA = predetermined time A, the process proceeds to step s22 in order to perform the predictive estimation control. Otherwise, the intake air amount calculation flow 1 is terminated and the process waits until the next trigger is received.

When the process proceeds to step s22, the fuel control intake air amount is calculated by predictive estimation control. This is composed of steps s38 to s59 as shown in FIGS.
First, preparations for predictive estimation control are made in steps s38 and s39. In steps s40 to s57, the estimated estimated downstream pressure and the estimated estimated in-cylinder pressure at IVC (= the downstream pressure for fuel control and the in-cylinder pressure for fuel control) are calculated by predictive estimation control. In step s58, the fuel control intake air amount is calculated from the fuel control cylinder pressure, and in step s59, the intake air amount calculation flow 1 is completed.

In step s38, CA ′ = CA is performed. CA ′ is a crank angle used when performing predictive estimation control. Then, P _{2_A} = P _{2_old} is executed in step s39 to store the estimated downstream pressure at the current time (= predetermined time A), and then the process proceeds to step s40.
Steps s40 to s57 are controls that loop until CA ′ reaches IVC.
First, in step s41, CA '= CA' +. DELTA.CA is executed and CA 'is advanced by .DELTA.CA.
Steps s42 to s56 are basically the same as steps s4 to s20, except that CA is CA ', as can be seen by comparing the flowcharts.
Since each corresponds as follows, detailed description is abbreviate | omitted.
“Steps s4 to s7 (the state where the intake valve is closed in the previous cycle (= CA−ΔCA) and the intake valve is closed at the present time (= CA))” and “steps s42 to s45”
“Steps s4 and s12 to s14 (the state where the intake valve is open in the previous cycle (= CA−ΔCA) and the intake valve is open at the present time (= CA))” and “steps s42 and s48 to s50”
“After s4, s12, s15 to s20, step s14 (the state where the intake valve is closed in the previous cycle (= CA−ΔCA) and the intake valve is opened at the present time (= CA))” and “s42, s48, s50 steps through s51 to s56 "
Note that “s4, s5, s8 to s11 steps are followed by s7 steps (the intake valve is open in the previous cycle (= CA−ΔCA) and the intake valve is closed at the present time (= CA))”. Since it is not necessary to calculate the predicted estimated downstream pressure after IVC in the predictive estimation control, the steps corresponding to steps s7, s10, and s11 of “steps s7, s8, and s8 to s11 are omitted” “s4, “Steps s5, s8, and s9” correspond to “steps s42, s43, s46, and s47”.

After executing loop control of steps s40 to s57 to calculate the downstream pressure for fuel control and the in-cylinder pressure for fuel control in IVC, the process proceeds to step s58.
In step s58, the intake air amount for fuel control is calculated from the in-cylinder pressure for fuel control, the in-cylinder volume at IVC, and the intake air temperature using the gas state equation. Then, after the calculated intake air amount for fuel control is transmitted to the engine control unit 8, the process proceeds to step s59.
In step _s59 , P _{2_old =} P _{2_A} is executed to prepare for real-time estimation control performed after receiving the next trigger. After processing step s59, the process waits until the intake air amount calculation flow 1 ends and the next trigger is received.

  By performing the above processing with the throttle control unit 7 provided for each cylinder during engine operation, in the first embodiment that does not include an airflow sensor or a pressure sensor, the fuel injection is started from the predetermined time A to the time when fuel injection is started. By estimating the fuel control intake air amount of the cylinder prior to the crank angle, highly accurate fuel injection control can be performed using the estimated fuel control intake air amount to the cylinder.

  Then, instead of calculating the flow rate of the throttle part, intake valve, and exhaust valve in total three places as in the prior art, only the throttle part flow rate is calculated and the throttle downstream pressure, in-cylinder pressure, intake air amount It is possible to reduce the calculation load by estimating.

  In the first embodiment, the intake air amount is estimated by the throttle control unit 7 and the fuel amount calculation is performed by the engine control unit 8. However, as a matter of course, these functions are performed by the engine control unit. 8, the intake air amount may be estimated by the engine control unit 8.

Embodiment 2. FIG.
In Embodiment 1, the sensor for detecting the throttle downstream pressure is not installed, and the throttle downstream pressure at the predetermined time A is estimated by real-time estimation control.
In the second embodiment, the throttle downstream pressure at the predetermined time A is detected by a pressure sensor. That is, based on the throttle downstream pressure at the predetermined time A detected by the pressure sensor, the prediction estimation control performed in the first embodiment is performed, thereby estimating the intake air amount for fuel control.
Similarly to the first embodiment, in the second embodiment, in order to reduce the calculation load in the estimation of the estimated downstream pressure and the intake air amount for fuel control as compared with the prior art, the intake valve closing model and the intake valve opening model are used. By using it, the flow rate of only the throttle part is calculated instead of calculating the flow rate of the throttle part, the intake valve part, and the exhaust valve part as in the prior art.

FIG. 20 shows an overall configuration diagram of the second embodiment. In the figure, the same reference numerals as those in FIG. 4 denote the same or corresponding parts.
FIG. 20 shows the same multiple throttle system as in the first embodiment, and only the first cylinder is shown as a representative. However, the second to fourth cylinders of the engine are configured in the same manner.
As can be seen from a comparison between FIG. 20 and FIG. 4 that is the overall configuration diagram of the first embodiment, the difference between the two is whether or not the pressure sensor 11 is provided in the throttle downstream portion 9.
20 is provided in each throttle downstream section 9 and transmits a throttle downstream pressure detection signal to each throttle control unit 7.
Further, as in the first embodiment, the intake valve closing model and the intake valve opening model used in the second embodiment are the same as those in the first embodiment, such as the configuration and formula, and the description thereof is omitted.

Next, a flowchart of the intake air amount estimation flow 2 performed by the throttle control unit 7 will be described.
FIG. 21 shows a flowchart of an intake air estimation flow 2 implemented in the second embodiment. In the intake air amount estimation flow 2, since the throttle valve 1 is an individually controlled multiple throttle system, the second embodiment is the same as the first embodiment. The valve opening model will be used.
Similarly to the first embodiment, the throttle control unit 7 incorporates a valve timing map (FIG. 15) of the intake valve using the throttle upstream pressure P ₁ value, the intake air temperature T ₁ value, and the crank angle as parameters. Leave in.
The intake air amount estimation flow 2 is performed when a trigger is sent from the engine control unit 8 to the throttle control unit 7 when the crank angle reaches a predetermined cycle A (calculated from a predetermined time A map (FIG. 19)). The estimated estimated downstream pressure, the estimated estimated in-cylinder pressure, and the intake air amount for fuel control are estimated by the estimated estimation control.
The intake air amount estimation flow 2 is composed only of control logic that performs predictive estimation control.
That is, in the intake air amount estimation flow 2 as in the intake air amount estimation flow 1, the equations (8) to (10) shown in the first embodiment, the gas state equations, and various maps (FIGS. 15 to 19). Is used to calculate the estimated estimated downstream pressure, the intake air amount for fuel control, and the like.

Hereinafter, each step will be described. In FIG. 21, regarding the s10 step and the s22 step, the same processing as that of the s10 step and the s22 step of the first embodiment is performed.
After receiving a trigger from the engine control unit 8, first, in ss 1 step, the crank angle, the engine speed, the throttle opening from the throttle actuator 6, and the throttle downstream pressure from the pressure sensor 11 are read from the engine control unit 8, and the ss 22 step is performed. move on.
In step s22, as described above, the same process as in step s22 of the first embodiment (that is, the same process as in steps s38 to s59) is performed to calculate the intake air amount for fuel control.
Thereafter, in step s10, the same process as in step s10 of the first embodiment is performed as described above, and a predetermined time A is calculated and transmitted to the engine control unit 8. After the s10 step processing, the intake air amount calculation flow 2 is terminated, and the process waits until the next trigger is received.
By performing the above processing in the throttle control unit 7 provided for each cylinder during engine operation, the intake air amount for fuel control using the pressure sensor 11 can be estimated.

  According to the second embodiment, as compared with the first embodiment, since the pressure sensor 11 is provided for each cylinder, the cost is increased. However, as can be seen by comparing the intake air amount estimation flow 1 and the intake air amount estimation flow 2, in the second embodiment, the intake air amount for fuel control can be estimated with simpler control logic. Since the pressure downstream of the throttle at the predetermined time A is detected by the pressure sensor 11, the intake air amount for fuel control can be estimated with higher accuracy than in the first embodiment.

Embodiment 3 FIG.
In the first and second embodiments, the present invention in the multiple throttle system has been described.
In the third embodiment, the present invention in the collective throttle system will be described.
At the same time, the atmospheric pressure correction and the intake air temperature correction, which were not applied in the first and second embodiments, are combined with the third embodiment and described.
In the third embodiment, as in the first embodiment, the throttle downstream pressure at the predetermined time A is estimated by the real-time estimation control, and then the fuel is injected by the prediction estimation control by the time when fuel injection is started prior to the crank angle. Estimate the amount of intake air for control.
Further, in the first and second embodiments, in the estimation of the estimated downstream pressure and the intake air amount for fuel control, in order to make the calculation load smaller than that of the prior art, by using the intake valve closing model and the intake valve opening model, Instead of calculating the passage flow rate at three locations of the throttle portion, the intake valve portion, and the exhaust valve portion as in the prior art, the passage flow rate of only the throttle portion is calculated.
In the third embodiment, a throttle part, an intake valve part, an exhaust valve part are used as in the prior art by using a collective throttle system model that models the intake passage from the upstream side of the throttle to the inside of each cylinder in consideration of volume changes. Instead of calculating the passage flow rate at these three locations, the calculation load is reduced by calculating the passage flow rate of only the throttle portion.
The intake air amount estimation model different from the intake valve closing model and the intake valve opening model used in the first and second embodiments is used because each cylinder is shielded by the throttle in the downstream portion of the throttle in the collective throttle system. Since at least one of the cylinders is always open, and when the intake valves of two or more cylinders are open, the cylinders of all the cylinders where the intake valves are open are always connected. This is because it is necessary to consider the internal volume.
In the third embodiment, the control for correcting the throttle upstream pressure and the intake air temperature used in the real-time estimation control and the prediction estimation control with sensor values is also performed.

Hereinafter, Embodiment 3 of the present invention will be described in detail with reference to the drawings.
FIG. 22 is an overall configuration diagram of the third embodiment. The control device for an internal combustion engine in FIG. 22 is a collective throttle system, which is a four-cylinder engine as an example.
Although only the first cylinder is representatively shown as the cylinder portion, the second to fourth cylinders of the engine are similarly configured. In the figure, components having the same name and the same reference numerals as those in FIGS. 4 and 20 are the same as those in FIGS. 4 and 20.

In FIG. 22, the engine is provided with a throttle valve 1 for limiting the intake amount, a fuel injection valve 2, an intake valve 3 and an exhaust valve 4 for each cylinder, and a crank angle sensor 5 in the engine body. The throttle valve 1 is driven by a throttle actuator 6 installed in the throttle valve 1, and the throttle valve 1 is electronically controlled by sending a throttle opening control signal to the throttle actuator 6 by a throttle control unit 12.
The throttle actuator 6 is provided with a TPS that detects the throttle opening, and transmits a throttle opening detection signal to the throttle control unit 12.
A throttle opening detection signal is input from the throttle actuator 6 to the throttle control unit 12, and an engine speed signal, a crank angle signal, a target intake air amount signal, an atmospheric pressure signal, and an intake air temperature signal are input from the engine control unit 13. .
A throttle opening control signal is output from the throttle control unit 12 to the throttle actuator 6, and a fuel control intake air amount signal is output to the engine control unit 13.
The throttle control unit 12 determines the target throttle opening from the throttle opening detection signal, fuel control intake air amount and target intake air amount signal, engine speed detection signal, crank angle signal, atmospheric pressure, intake air temperature, etc. From this, estimation processing such as the intake air amount for fuel control is performed. In FIG. 22, the throttle downstream pressure is the pressure in the throttle downstream portion 14.

The engine control unit 13 includes an accelerator pedal position detection signal from the accelerator position sensor, a crank angle detection signal from the crank angle sensor 5, an intake air amount signal for fuel control from the throttle control unit 12 of each cylinder, and an atmospheric pressure from the atmospheric pressure sensor 15. An intake air temperature detection signal is input from the detection signal and the temperature sensor 16.
It is assumed that the atmospheric pressure sensor 15 and the temperature sensor 16 are installed in the intake passage between the throttle valve 1 and the air cleaner 17.
Then, a fuel injection control signal is output from the engine control unit 13 to the fuel injection valve 2 of each cylinder, and an engine speed signal, a crank angle signal, a target intake air amount signal, an atmospheric pressure signal, and an intake air temperature signal are output to the throttle control unit 12. Is done.
The fuel injection valve 2 is injected independently for each cylinder.
The engine control unit 13 detects the engine speed and the crank angle from the crank angle detection signal, determines the target intake air amount from the accelerator depression amount and the intake air amount for fuel control, and the like, from the intake air amount for fuel control and the target air-fuel ratio, etc. The fuel injection amount is determined.

By the way, in the prior art, the flow downstream of the throttle valve, the intake valve, and the exhaust valve is estimated to estimate the downstream pressure of the throttle, the in-cylinder pressure, the intake air amount, and the like. In the third aspect, in order to achieve a reduction in calculation load by estimating only the throttle portion passage flow rate and estimating the throttle downstream pressure, in-cylinder pressure, intake air amount, etc., A collective part throttle system model (FIG. 23), which is an intake air amount estimation model that models the intake passage from the upstream to the inside of each cylinder in consideration of the volume change, is used.
Hereinafter, the collective throttle system model used in the third embodiment will be described with reference to FIG.

In FIG. 23, a collective throttle system model is a model for estimating the throttle passage flow rate and estimating the throttle downstream pressure, in-cylinder pressure, intake air amount, and the like. The throttle upstream part, the throttle opening part, and the throttle part ~ It is composed of each cylinder through the throttle downstream to the intake valve.
The throttle upstream portion to the throttle downstream portion have the same configuration as the intake valve closed model and the intake valve open model described in the first embodiment, and the throttle upstream portion has a throttle opening based on the throttle upstream pressure P ₁ and the intake air temperature T _1. The portion is composed of a throttle flow path area _AT, and the intake air passing through the throttle opening receives pressure from the throttle upstream pressure P ₁ and the throttle downstream pressure P ₂ .
Further, the throttle downstream portion is configured as a throttle downstream pressure P ₂ and the throttle downstream volume V ₂ from the intake air temperature T _1.
As for the in-cylinder configuration, the in-cylinder configuration is the same as the in-cylinder structure in the intake valve open model, in-cylinder pressure (P _{4 to} P ₇ ), in-cylinder volume (V _{4 to} V ₇ ), and intake air temperature. It consists T _1, cylinder volume (V ₄ ~V ₇₎ varies according to the crank angle. With regard to the in-cylinder pressure (P _{4 to} P ₇ ), it is assumed that the in-cylinder pressure and the throttle downstream pressure of each cylinder in which the intake valve is open are balanced except when the intake valve starts to open. Note throttle upstream pressure P ₁ is handled as a substantially atmospheric pressure, intake air temperature T ₁ of the treated as constant across.

When estimating the throttle passage flow rate at the time when the intake valve of a cylinder starts to open, firstly, the "throttle downstream pressure and the in-cylinder pressure of each cylinder where the intake valve is open" and the in-cylinder cylinder at the time when the intake valve starts to open. It is necessary to estimate the pressure when the pressure is balanced.
The reason for this is that since the exhaust stroke is just before the intake valve is opened, the cylinder in the cylinder is at substantially atmospheric pressure, and when the intake valve is opened in this state, the pressure in the cylinder at approximately atmospheric pressure is negative. And in-cylinder of each cylinder in which the intake valve is open ”is in a communication state, and“ in-cylinder pressure in each cylinder in which the throttle valve downstream pressure and intake valve are open ”and the in-cylinder pressure of the cylinder are in equilibrium. is there.
The throttle downstream pressure after pressure equilibrium and the in-cylinder pressure of each cylinder in which the intake valve is open are estimated from the following equation based on the gas equation of state.

  By the way, like the intake valve opening model used in the first and second embodiments, the throttle downstream pressure and the in-cylinder pressure change due to the change in the in-cylinder volume of each cylinder. Therefore, when estimating the flow rate through the throttle, first, it is assumed that there is no flow rate from the throttle during a predetermined period, and then the throttle downstream pressure and the in-cylinder pressure when the in-cylinder volume of each cylinder changes are estimated (the following) (12)), and the throttle flow rate is estimated based on the estimated throttle downstream pressure and in-cylinder pressure (the following equations (13) and (14)).

The above formulas (13) and (14) are similar to the formulas (2) and (3) of the first embodiment, and are an index indicating whether or not the speed of the intake air passing through the throttle becomes the speed of sound. The pressure ratio is divided into cases. In the when starts to open the first to fourth cylinders one of the intake valve (11), after estimating the P _{2_OPEN_IVO,} it the equation (12) in the P _{2_OPEN_old} per unit time passing through the throttle flow rate estimation as To do. The throttle flow rate per unit time, the predetermined period, the current throttle downstream pressure (assuming that there is no flow rate from the throttle), the cylinder pressure P ′ _{2_OPEN_old of} each cylinder in which the intake valve is open, and the throttle From the sum of the downstream volume V ₂ and the current “in-cylinder volume ΣV _{k_new} of each cylinder in which the intake valve is open” and the intake air temperature T ₁ , the current throttle downstream pressure and intake valve are determined using the gas equation of state. Estimate the in-cylinder pressure of each open cylinder.
The estimated throttle downstream pressure and the in-cylinder pressure of each cylinder in which the intake valve is open are further used as a basis for estimating the throttle downstream pressure and the in-cylinder pressure of each cylinder in which the intake valve is open after a predetermined period. The above processing is performed every predetermined period.

Next, the intake air amount estimation flow 3 performed by the throttle control unit 12 will be described. 24 to 31 are flowcharts of the intake air estimation flow 3. FIG.
In the intake air amount estimation flow 3, as described above, the collective part throttle system model of FIG. 23 is used.
In addition, the throttle control unit 12 incorporates a valve timing map (FIG. 32 (a): used for determination of intake valve opening / closing) of each intake valve using the crank angle as a parameter.

The intake air amount estimation flow 3 is performed when a trigger sent from the engine control unit 13 to the throttle control unit 12 is received every predetermined period ΔCA based on the crank angle, and the predicted estimated downstream pressure and predicted value are predicted by the predicted estimation control. The estimated downstream pressure and the estimated in-cylinder pressure are estimated by the estimated in-cylinder pressure, the intake air amount for fuel control, and real-time estimation control.
The intake air amount estimation flow 3 includes control logic (FIGS. 29 to 31) that performs predictive estimation control, control logic that performs real-time estimation control (control logic of sss1, sss2, and sss4 to sss23 steps), and intake air It consists of control logic (sss0 step) for correcting temperature and atmospheric pressure.
In the prediction estimation control and the real-time estimation control, the estimated estimated downstream pressure, the intake air amount for fuel control, and the like are calculated using the above equations (11) to (14) and the gas state equation.
In the intake air amount estimation flow 3, based on the throttle passage flow rate per unit time and the gas state equation shown in the above formulas (13) and (14), the throttle downstream pressure that changes depending on the throttle passage flow rate during ΔCA is calculated. Calculated from the following formula.

  Further, as described in the above equation (11), when estimating the throttle passage flow rate when the intake valve of any cylinder starts to open, first, the throttle downstream pressure and the intake valve are opened when the intake valve starts to open. It is necessary to estimate the pressure when the in-cylinder pressure and the in-cylinder pressure of the cylinder are in equilibrium. In the intake air amount estimation flow 3, the pressure at equilibrium is calculated from the following equation based on the equation (11).

Further, as shown in equation (12), when calculating the downstream pressure of the throttle and the in-cylinder pressure of each cylinder with the intake valve open in the collective throttle system model, there is no flow rate from the throttle between ΔCA. As a result, it is necessary to calculate the throttle downstream pressure after the cylinder volume of each cylinder changes and the cylinder pressure of each cylinder where the intake valve is open.
In the intake air amount calculation flow 3, the throttle downstream pressure and the cylinder pressure after the cylinder volume of each cylinder is changed are calculated by the following equation (17).

Using the above equations (15) to (17), the throttle downstream pressure and the in-cylinder pressure of each cylinder in which the intake valve is open are estimated or estimated.
The estimated amount of intake air sucked into the cylinder when the intake valve is fully closed using the gas equation of state from the cylinder pressure, cylinder volume and intake air temperature estimated by predictive estimation I can do it.

Hereinafter, each step will be described.
In the intake air amount calculation flow 3, it is assumed that the current crank angle in equations (15) to (17) is CA1, the calculation cycle is ΔCA1, and values are substituted into CA1 and ΔCA1.
In FIG. 24, first, in the sss0 step, the atmospheric pressure and intake air temperature sensor values are read from the engine control unit 13, and the read atmospheric pressure sensor value is substituted for P ₁ and the intake air temperature sensor value is substituted for T ₁ . To do.
In the sss1 step, it is confirmed whether the engine is operating. If it is operating, the process proceeds to the sss2 step, and if it is stopped, the process proceeds to the sss3 step.
When the engine is stopped, the intake air flow rate is accumulated in the throttle downstream volume via the throttle, so that the throttle downstream pressure is recovered to the atmospheric pressure. Therefore, in the sss3 step, “P _{2_old} = P ₁ ” is executed, the intake air amount calculation flow 3 is terminated, and the process waits until the next trigger is received.

When the process proceeds from the sss1 step to the sss2 step, the crank angle, the engine speed, and the throttle opening from the throttle actuator 6 are read from the engine control unit 13, and the process proceeds to the sss4 step.
In the sss4 step, by referring to the valve timing map of the intake valve of each cylinder (FIG. 32 (a)), any cylinder between the previous cycle (= CA−ΔCA) and the current time (= CA) Determine if IVO has not been reached.
If none of the cylinders has reached IVC or IVO, the process proceeds to step sss5 (FIG. 26). If any of the cylinders has reached IVC or IVO, the process proceeds to step sss6.

When the process proceeds to the sss5 step, real-time estimation control is performed from the sss5 step and the sss23 step, and the estimated downstream pressure at CA and the estimated in-cylinder pressure of each cylinder where the intake valve is open are calculated.
First, ΔCA1 = ΔCA and CA1 = CA are performed in the sss5 step, and the process proceeds to the sss23 step.
In the sss23 step, the estimated downstream pressure is calculated.
As shown in FIG. 27, the estimated downstream pressure calculation includes sss30 to sss41 steps.
First, in step sss30, the time term S is calculated from the engine speed and ΔCA1.
Thereafter, in step _sss31 , the sum ΣV _{k_new} of the in-cylinder volume of each cylinder (including the cylinder that has reached IVC) in _CA1 is calculated from CA1 and the in-cylinder volume map, and is substituted for V _new. , V _new and V ₂ are used to calculate the volume term V.

In the sss32 step, the estimated downstream pressure at CA1 (assuming that there is no flow rate from the throttle) and the estimated in-cylinder pressure of each cylinder in which the intake valve is open are calculated using Equation (17).
In step _sss33 , P _{2_old} = P _{2_new} is executed. In step _sss34 , the speed term H is calculated from (P _{2_old /} / P ₁ ) and (P ₁ ² / T ₁ ) and the speed term map. The area term D is calculated from the area term map and the process proceeds to the sss36 step.
In step sss36, the estimated downstream pressure at CA1 and the estimated in-cylinder pressure of each cylinder in which the intake valve is open are calculated from the equation (15).

Thereafter, the process proceeds to the sss37 step, and it is determined from the valve timing map (FIG. 32A) of each intake valve whether CA1 is IVC or IVO of any of the first to fourth cylinders.
When CA1 is not IVC or IVO of any of the first to fourth cylinders, proceed to sss38,
After executing V _old = V _new and executing P _{2_old} = P _{2_new} in the sss 41 step, the process proceeds to the sss 24 step.
In step sss37, if CA1 is IVC or IVO of any of the first to fourth cylinders, ΣV _{k_old} is calculated using the in-cylinder volume map in steps sss39 and sss40. This is because V _new is “the sum of the cylinder capacities of the cylinders (including cylinders that have reached IVC) in which the intake valve is open”, whereas V _old is “each cylinder in which the intake valve is open ( This is because if the CA1 is IVC or IVO of any of the 1st to 4th cylinders, V _old = V _new cannot be simply set. .
Accordingly after having calculated the [sigma] v _{K_new} "sum of cylinder volume of each cylinder intake valve is open (including IVC)" sss39 in CA1 from CA1 and cylinder volume map in step, V _old at sss40 step = [sigma] v _{After executing k_new} and executing P _{2_old} = P _{2_new} in the sss 41 step, the process proceeds to the sss 24 step.

By the way, in sss4 step, it is determined whether any cylinder has reached IVC or IVO during the previous cycle (= CA-ΔCA) to the present time (= CA), and any cylinder has reached IVC or IVO. Therefore, when proceeding to the sss6 step, in the sss6 to sss23 steps, ΔCA is divided for each IVC or IVO to calculate the estimated downstream pressure or the like.
As described in the equations (11) to (17), for example, in the case of IVO, the cylinder pressure of the cylinder at which the intake valve starts to open and the “cylinder downstream pressure and the cylinder pressure of each cylinder at which the intake valve is opened” This is because processing such as the need to calculate the pressure when "" is in equilibrium is performed.

First, in step sss6, by referring to the valve timing map of the intake valve of each cylinder (FIG. 32 (a)), it is determined whether it is the IVO that has reached earlier among the IVCs or IVOs of any of the reached cylinders. Determine whether.
If the IVO arrives earlier, the process proceeds to the sss7 step. If the IVC arrives earlier, the process proceeds to the sss15 step.

When proceeding to the sss7 step, ΔCA1 = IVO_F− (CA−ΔCA) and CA1 = IVO_F are performed in order to calculate the estimated downstream pressure at the previously reached IVO (hereinafter referred to as IVO_F). Proceed to step sss8.
In the sss8 step, the estimated downstream pressure calculation described in the sss23 step is performed, the estimated downstream pressure at IVO_F and the estimated in-cylinder pressure of each cylinder in which the intake valve is open are calculated, and the process proceeds to the sss9 step.
In the sss9 step, IVO calculation is performed.

As shown in FIG. 28, the IVO calculation is composed of sss42 and sss43 steps.
First, in the sss42 step, estimate the pressure when the "in-cylinder pressure of each cylinder where the intake valve is open" and the in-cylinder pressure of the cylinder where the intake valve begins to open is balanced at IVO (here IVO_F) To do. This is calculated from equation (16).
Thereafter, P _{2_old} = P _{2_new} is executed in the sss 43 step, and the process proceeds to the sss 10 step.

In step sss10, after reaching IVO_F, whether or not any of the cylinders reaches IVC is determined in the same manner as in sss6 until CA is reached.
If any of the cylinders reaches IVC, the process proceeds to step sss11. If any of the cylinders does not reach IVC, the process proceeds to step sss14.

When the process proceeds to the sss11 step, ΔCA1 = IVC_L−IVO_F and CA1 = IVC_L are performed in order to calculate the estimated downstream pressure or the like in the IVC (hereinafter referred to as IVC_L) reached after the IVO_F, and the sss12 step is performed. move on.
In the sss12 step, the estimated downstream pressure calculation described in the sss23 step is performed to calculate the estimated downstream pressure at IVC_L and the estimated in-cylinder pressure of each cylinder in which the intake valve is open.
After that, in step sss13, in order to calculate the estimated downstream pressure at CA, etc., ΔCA1 = CA−IVC_L and CA1 = CA are performed and the process proceeds to step sss23, where the estimated downstream pressure and intake valve at CA are opened. After calculating the estimated in-cylinder pressure of each cylinder, the process proceeds to step sss24.

  In addition, when the IVC of any cylinder is not reached before reaching CA after reaching IVO_F, that is, when the process proceeds from the sss10 step to the sss14 step, the estimated downstream pressure at the CA is calculated in the sss14 step. , ΔCA1 = CA−IVO_F and CA1 = CA are performed, and the process proceeds to the sss23 step. After calculating the estimated downstream pressure at CA and the estimated in-cylinder pressure of each cylinder in which the intake valve is open, the process proceeds to the sss24 step.

By the way, in the sss6 step, it is determined whether the IVC or IVO of any of the cylinders that have arrived earlier is the IVO. If the IVC has reached earlier, the process proceeds to the sss15 step. In order to calculate the estimated downstream pressure at the reached IVC (hereinafter referred to as IVC_F), ΔCA1 = IVC_F− (CA−ΔCA) and CA1 = IVC_F are performed, and the process proceeds to sss16 step.
In the sss16 step, the estimated downstream pressure calculation described in the sss23 step is performed to calculate the estimated downstream pressure at IVC_F and the estimated in-cylinder pressure of each cylinder in which the intake valve is open, and the process proceeds to the sss17 step.
In step sss17, after reaching IVC_F, whether or not any of the cylinders reaches IVO is determined in the same manner as in sss6 until CA is reached.
If any of the cylinders reaches IVO, the process proceeds to step sss18, and if none of the cylinders reaches IVC, the process proceeds to step sss22.

When proceeding to the sss18 step, ΔCA1 = IVO_L−IVC_F and CA1 = IVO_L are performed to calculate the estimated downstream pressure or the like in the IVO (hereinafter referred to as IVO_L) reached after the IVC_F, and the sss19 step is performed. move on.
In the sss19 step, the estimated downstream pressure calculation described in the sss23 step is performed to calculate the estimated downstream pressure at IVO_L and the estimated in-cylinder pressure of each cylinder in which the intake valve is open, and the process proceeds to the sss20 step.
In the sss20 step, the IVO calculation described in the sss9 step is performed, and “the throttle downstream pressure and the in-cylinder pressure of each cylinder in which the intake valve is open” in IVO (here, IVO_L) and the cylinder cylinder in which the intake valve starts to open Estimate the pressure when the internal pressure is balanced.
Thereafter, in order to calculate the estimated downstream pressure and the like at CA in step sss21, ΔCA1 = CA−IVO_L and CA1 = CA are performed and the process proceeds to step sss23, and the estimated downstream pressure and intake valve at CA are opened. After calculating the estimated in-cylinder pressure of each cylinder, the process proceeds to the sss24 step.

In addition, when none of the cylinders reaches IVC until reaching CA after reaching IVC_F, that is, when proceeding from sss17 step to sss22 step, in order to calculate the estimated downstream pressure and the like at CA in sss22 step , ΔCA1 = CA−IVC_F and CA1 = CA are performed, and the process proceeds to the sss23 step. After calculating the estimated downstream pressure at CA and the estimated in-cylinder pressure of each cylinder in which the intake valve is open, the process proceeds to the sss24 step.
In the above sss1 to sss23 steps, the estimated downstream pressure and the estimated in-cylinder pressure of each cylinder in which the intake valve is open are calculated by real-time estimation control.

In steps sss24 to sss25, the prediction estimation control execution determination and the prediction estimation control are performed.
First, in the sss24 step, it is determined whether or not CA is the predetermined timing A of any cylinder. The predetermined time A of each cylinder is calculated from the engine speed and a predetermined time A map (FIG. 32 (b): a map using the engine speed as a parameter).
As can be seen from FIG. 32 (b), the predetermined timing A of each cylinder is shifted by a predetermined period ΔCA toward the start of predictive estimation control earlier in order to secure the estimated processing time as the internal combustion engine speed increases. Yes.

In the sss24 step, if CA is not the predetermined time A of any cylinder, the process proceeds to sss 26 step, and if CA is the predetermined time A of any cylinder, the process proceeds to sss25 step.
When the process proceeds from the sss24 step to the sss25 step, the fuel control intake air amount is calculated by predictive estimation control in the sss25 step.
This is composed of sss44 to sss74 steps as shown in FIGS. First, preparations for predictive estimation control are made in steps sss44 to sss46.
In steps sss47 to sss71, the predicted estimated downstream pressure at the IVC of the cylinder and the estimated estimated in-cylinder pressure of each cylinder in which the intake valve is open (which is the target cylinder for calculating the intake air amount for fuel control) by predicted estimation control ( = Downstream pressure for fuel control and in-cylinder pressure for fuel control).
In step sss72, the intake air amount for fuel control is calculated from the in-cylinder pressure for fuel control, and the process proceeds to step sss26 through steps sss73 and sss74.

First, in step sss44, CA ′ = CA is performed. CA ′ is a crank angle used when performing predictive estimation control. Then, P _{2_A} = P _{2_old} is _executed in the sss 45 step, and V _A = V _old is executed in the sss 46 step, and “Estimated downstream pressure and intake valve are open at the present time (= predetermined timing A of the cylinder)” The process proceeds to the sss47 step after storing the “estimated in-cylinder pressure of the cylinder” and “the sum of the in-cylinder volume of each cylinder (including the cylinder that has reached IVO) whose intake valve is open”.

Steps sss47 to sss71 are controls that loop until CA ′ reaches the IVC of the cylinder.
First, in step sss48, CA ′ = CA ′ + ΔCA is executed and CA ′ is advanced by ΔCA.
The sss49 to sss 70 steps are basically the same as the sss 4 to sss 23 steps except that CA is CA ′ as can be seen by comparing the flowcharts.
Since each corresponds as follows, detailed description is abbreviate | omitted.
“Sss4, sss5, sss23 steps (the state where neither IVO nor IVC of any cylinder is reached between CA−ΔCA and CA)” and “sss49, sss50, sss70 steps”
“Sss4, sss6 to sss10, sss14, sss23 steps (a state in which the IVO of any cylinder is reached between CA-ΔCA and CA)” and “sss49, sss51 to sss55, sss60, sss70 steps”

Regarding “sss4, sss6 to sss13, and sss23 steps (a state in which the IVO of any cylinder is first reached after CA-ΔCA to CA, and then reaches the IVC of any cylinder)” The purpose of the predictive estimation control is to calculate the predicted estimated downstream pressure at IVC of the cylinder and the predicted estimated in-cylinder pressure of each cylinder where the intake valve is open, so “sss4, sss6 to sss13, sss23 steps” And “sss49, sss51 to sss57, sss59, sss70 steps” and after the sss57 step (calculate the estimated estimated downstream pressure at IVC_L and the estimated estimated in-cylinder pressure of each cylinder with the intake valve open) A control logic (sss 58 step) for determining whether IVC_L is the IVC of the cylinder is incorporated.
In the sss 58 step, if IVC_L is not the IVC of the cylinder, the process proceeds to the sss 59 step, and if IVC_L is the IVC of the cylinder, the process proceeds to the sss 71 step to exit the loop.

Similarly, “sss4, sss6, sss15 to sss21, sss23 steps (in the state from CA-ΔCA to CA, after first reaching the IVC of any cylinder and then reaching the IVO of any cylinder) ”Corresponds to the“ sss49, sss51, ss61, sss62, sss64 to sss68, sss70 steps ”and the sss62 step (the predicted estimated downstream pressure in IVC_F and the predicted estimated in-cylinder pressure of each cylinder in which the intake valve is open). After the calculation, the same control as the sss 58 step is incorporated in the sss 63 step.
Further, in “sss4, sss6, sss15 to sss17, sss22, sss23 steps (a state in which the IVC of any cylinder is reached between CA−ΔCA and CA)”, “sss49, sss51, sss61, sss62, sss64, sss69, sss70 step "and sss62 step (calculate the predicted estimated downstream pressure at IVC_F and the predicted estimated in-cylinder pressure of each cylinder with the intake valve open) after sss63 step, the same control as the sss58 step Incorporate

After calculating the predicted estimated downstream pressure at IVC of the cylinder and the predicted estimated in-cylinder pressure (= downstream pressure for fuel control and in-cylinder pressure for fuel control) of each cylinder in which the intake valve is open, the process proceeds to step sss72.
In the sss 72 step, the fuel control intake air amount is calculated from the fuel control cylinder pressure, the cylinder volume at the IVC of the cylinder and the intake air temperature using the gas state equation.
Then, after the calculated intake air amount for fuel control is transmitted to the engine control unit 13, the process proceeds to step sss73.
In sss73 step, implementing the _P 2_old = P _{2_A,} in sss74 step, and carrying out the V _old = V _A provided in real time estimation control performed after receiving the next trigger, the process proceeds to sss26 step.

In the sss26 step, it is determined whether or not CA is a calculation time of a predetermined time A for each cylinder.
The calculation time of the predetermined time A is set to a frequency of about once every 4 stroke cycles such as TDC (top dead crank) of the intake stroke of the first cylinder.
If CA is not the predetermined time A calculation time, the intake air amount calculation flow 3 is terminated, and the process waits until the next trigger is received. If CA is the predetermined time A calculation time, the process proceeds to step sss27.
In the sss27 step, the predetermined time A of each cylinder is calculated from the engine speed and the predetermined time A map (FIG. 32 (b)), the intake air amount calculation flow 3 is terminated, and the process waits until the next trigger is received.

  By performing the above processing from the engine start to the engine stop by the throttle control unit 12, in the third embodiment which is a collective throttle system, as in the first and second embodiments, the estimated fuel to the cylinder is estimated. Highly accurate fuel injection control can be performed using the control intake air amount.

  In the third embodiment, an atmospheric pressure sensor and a temperature sensor are installed upstream of the throttle valve, and the atmospheric pressure and the intake air temperature are corrected at regular intervals, thereby more accurately estimating the intake air amount for fuel control. Can be implemented.

  The atmospheric pressure and intake air temperature correction by the atmospheric pressure sensor and the temperature sensor is performed by installing the atmospheric pressure sensor and the temperature sensor upstream of the throttle valve and incorporating the same correction control as in the third embodiment. 2 is also possible.

4 is a stroke table of each cylinder showing a relationship between a timing of starting fuel injection and a reference intake air amount in a conventional four-cylinder engine. It is the figure which showed the relationship between "the amount of intake air used by fuel amount calculation" and "actual amount of intake air" at the time of the transition in the prior art. It is the figure which showed the relationship between actual throttle downstream pressure, estimated downstream pressure, and estimated estimated downstream pressure. 1 is an overall configuration diagram of a control device for an internal combustion engine according to Embodiment 1 of the present invention. It is a figure showing the intake valve closing model in Embodiment 1 of this invention. It is a figure showing the intake valve opening model in Embodiment 1 of this invention. It is a flowchart of the intake air amount estimation flow 1 in Embodiment 1 of this invention. It is a partial flowchart of the intake air amount estimation flow 1 in Embodiment 1 of this invention. It is a partial flowchart of the intake air amount estimation flow 1 in Embodiment 1 of this invention. It is a partial flowchart of the intake air amount estimation flow 1 in Embodiment 1 of this invention. It is a partial flowchart of the intake air amount estimation flow 1 in Embodiment 1 of this invention. It is a partial flowchart of the intake air amount estimation flow 1 in Embodiment 1 of this invention. It is a partial flowchart of the intake air amount estimation flow 1 in Embodiment 1 of this invention. It is a partial flowchart of the intake air amount estimation flow 1 in Embodiment 1 of this invention. It is a valve timing map of an intake valve in Embodiments 1 and 2 of this invention. It is an area term map in Embodiment 1, 2 of this invention. It is a speed term map in Embodiment 1, 2 of this invention. It is a cylinder volume map in Embodiment 1, 2 of this invention. It is the predetermined time A map in Embodiment 1, 2 of this invention. It is a whole block diagram of the control apparatus for internal combustion engines by Embodiment 2 of this invention. It is a flowchart of the intake air amount estimation flow 2 in Embodiment 2 of this invention. It is a whole block diagram of the control apparatus for internal combustion engines by Embodiment 3 of this invention. It is a figure showing the gathering part throttle system model in Embodiment 3 of this invention. It is a partial flowchart of the intake air amount estimation flow 3 in Embodiment 3 of this invention. It is a partial flowchart of the intake air amount estimation flow 3 in Embodiment 3 of this invention. It is a partial flowchart of the intake air amount estimation flow 3 in Embodiment 3 of this invention. It is a partial flowchart of the intake air amount estimation flow 3 in Embodiment 3 of this invention. It is a partial flowchart of the intake air amount estimation flow 3 in Embodiment 3 of this invention. It is a partial flowchart of the intake air amount estimation flow 3 in Embodiment 3 of this invention. It is a partial flowchart of the intake air amount estimation flow 3 in Embodiment 3 of this invention. It is a partial flowchart of the intake air amount estimation flow 3 in Embodiment 3 of this invention. FIG. 6 is a valve timing map of an intake valve of each cylinder and a predetermined timing A map of each cylinder in Embodiment 3 of the present invention. It is a speed term map in Embodiment 3 of this invention.

Explanation of symbols

1: Throttle valve 2: Fuel injection valve 3: Intake valve 4: Exhaust valve 5: Crank angle sensor 6: Throttle actuator 7, 12: Throttle control unit 8, 13: Engine control unit 9, 14: Throttle downstream part 10: Cylinder 11: Pressure sensor 15: Atmospheric pressure sensor 16: Temperature sensor 17: Air cleaner

Claims (11)

Intake air amount for controlling the intake air amount to each cylinder in each of the independent intake pipes, one end of which is connected to the intake valve of each cylinder of the internal combustion engine having a plurality of cylinders and the other end is connected to the collecting portion of each cylinder In a control device for an internal combustion engine of a port injection type that arranges a control means and performs exhaust stroke injection,
An intake valve closing model that models the intake passage from the upstream of the intake air amount control means to the intake valve, and an intake valve opening that models the intake passage from the upstream of the intake air amount control means to the cylinder in consideration of volume changes Two intake air quantity estimation models of the model, a flow path area detecting means for detecting a flow passage area of the intake air quantity control means, a downstream pressure detecting means for detecting a pressure downstream of the intake air quantity control means, and an internal combustion engine Provided with a rotational speed detection means, the two intake air quantity estimation models, the upstream pressure and the downstream pressure of the intake air quantity control means, the flow passage area of the intake air quantity control means, the internal combustion engine speed, and the cylinder volume Using the intake air temperature, the in-cylinder pressure and the intake air amount sucked into the cylinder at the time when the intake valve of the cylinder is completely closed after the fuel injected this time is sucked into the cylinder. Until the start of fuel injection An internal combustion engine control apparatus characterized by estimating When estimating the amount of intake air intake valve by the time of starting the fuel injection is sucked into the cylinder at the time of completely closed in order to calculate the fuel injection amount of the internal combustion engine, completely closing the intake valve is estimated The estimated estimated downstream pressure at that time is the in-cylinder pressure when the intake valve is fully closed, and the in-cylinder pressure and the in-cylinder volume when the intake valve is fully closed 2. The control apparatus for an internal combustion engine according to claim 1, wherein an intake air amount sucked is estimated.   Predetermined estimated downstream pressure, upstream pressure of intake air amount control means, flow path area of intake air amount control means, in-cylinder volume, internal combustion engine speed, intake air temperature The estimated estimated downstream pressure at the time when the intake valve is fully closed is estimated by repeatedly estimating the estimated estimated downstream pressure after a predetermined period from the previous time. Control device for internal combustion engine   The timing for starting the estimation of the estimated estimated downstream pressure is a predetermined timing before the timing for starting the fuel injection, and the predetermined timing is estimated with respect to the timing for starting the fuel injection as the engine speed increases. 4. The control apparatus for an internal combustion engine according to claim 3, wherein the timing for starting the estimation of the downstream pressure is shifted earlier. The downstream pressure is estimated from the previously estimated downstream pressure, the upstream pressure of the intake air amount control means, the flow passage area of the intake air amount control means, the cylinder volume, the internal combustion engine speed, and the intake air temperature. A control device for an internal combustion engine according to any one of claims 1 to 4. 6. The control apparatus for an internal combustion engine according to claim 5 , wherein the downstream pressure is estimated at predetermined intervals according to a crank angle. The control device for an internal combustion engine according to any one of claims 1 to 4 , further comprising a sensor for detecting a downstream pressure, wherein the downstream pressure is based on an output of the sensor. The control apparatus for an internal combustion engine according to any one of claims 1 to 7 , wherein the intake air amount control means is a throttle valve, and the flow passage area is set based on a throttle opening. The internal combustion engine speed detection means is a sensor capable of detecting a crank angle, and detects the internal combustion engine speed and a cylinder volume set based on the crank angle. The control apparatus for an internal combustion engine according to any one of claims 8 An internal combustion engine provided with the atmospheric pressure detecting means, based on the pressure detected by the atmospheric pressure detecting means, according to claim 1 to claim 9, characterized in that to correct the upstream pressure of the intake air amount control means The control device for an internal combustion engine according to any one of In an internal combustion engine provided with the intake air temperature detecting means, based on the intake air temperature detected by the intake air temperature detecting means, to any of claims 1 to 10, characterized in that to correct the intake air temperature The control apparatus for internal combustion engines as described.

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