JP4536104B2 - Control device for internal combustion engine - Google Patents

Description

  The present invention relates to a control device for an internal combustion engine, and more particularly to a control device for an internal combustion engine that controls a throttle opening so that a target intake air flow rate can be obtained.

  In recent years, the output shaft torque of an internal combustion engine, which is a physical quantity that directly affects vehicle control, is used as a required driving force value from the driver or vehicle side, and the internal combustion engine is controlled using this torque as a target value for the output of the internal combustion engine. Techniques have been proposed for obtaining good running performance by determining the amount of control, the amount of air, the amount of fuel, or the ignition timing. Furthermore, it is generally known that the control amount that has the greatest influence on the output shaft torque of the internal combustion engine among the control amounts for controlling the internal combustion engine is the air amount. For controlling the air amount with high accuracy, Technology has also been proposed.

  For example, in an internal combustion engine controller that controls the throttle opening by driving an actuator connected to the throttle of the internal combustion engine, the target intake air flow rate corresponding to the target torque of the internal combustion engine is changed to the differential pressure before and after the throttle and the air passage. There has been proposed a control device that is applied to an orifice flow rate formula based on an area and a flow coefficient, obtains a target opening area of the throttle, and sets a throttle opening that achieves the target opening area of the throttle ( For example, see Patent Document 1).

  According to the control device disclosed in Patent Document 1, when the throttle opening degree for achieving the target intake air flow rate is calculated by applying to the flow rate equation of the orifice, environmental conditions such as atmospheric pressure and intake air temperature change. Even when exhaust gas is introduced into the intake pipe (hereinafter referred to as EGR), the target intake air flow rate can be satisfactorily achieved.

  However, in the control device, in the throttle whose opening area changes according to the operating state, the flow coefficient that greatly affects the shape and opening area of the throttle is determined by the rotational speed of the internal combustion engine and the intake pipe pressure (hereinafter referred to as the intake manifold pressure). However, it is difficult to accurately set the flow coefficient when the throttle opening and the opening area are not determined. For this reason, there is a problem that the throttle target opening area for obtaining the target intake air flow rate cannot be accurately calculated, and a deviation occurs between the target intake air flow rate and the actual intake air flow rate. Furthermore, it is not easy to obtain the flow coefficient in advance and set it as a map.

  In order to solve this problem, the applicant applies the target intake air flow rate to an orifice flow rate equation based on the differential pressure before and after the throttle, the air passage area, and the flow coefficient, and the effective opening area and flow rate of the throttle. The target effective opening area of the throttle, which is the product of the coefficient, is obtained, and the target throttle opening is calculated using the relationship between the effective opening area and the throttle opening that is adapted in advance, without setting the flow coefficient, A control device for an internal combustion engine that calculates a throttle opening for obtaining a target intake air flow rate more accurately has been proposed (see, for example, Patent Document 2).

  However, in the technique disclosed in Patent Document 1 or Patent Document 2, due to manufacturing variations of individual throttle bodies, the actual effective opening area and flow coefficient vary even at the same throttle opening. Therefore, there is a problem that the intake air flow rate changes for each throttle body.

  Further, the calculated effective opening area varies due to variations and estimation errors of sensors that measure intake manifold pressure, atmospheric pressure, or intake air temperature. As described above, there is a problem that the actual intake air flow rate varies with respect to the target intake air flow rate due to variations in the throttle body and various sensors and various estimation errors.

  In order to solve this problem, the applicant of the present application, in Japanese Patent Application No. 2006-231950, which is an earlier application, calculates the actual value at the target throttle opening from the intake air flow rate at the target throttle opening and the flow rate equation of the orifice. The effective opening area is calculated, and the learning throttle opening is calculated from the actual effective opening area using the relation between the effective opening area and the throttle opening that is adapted in advance. Based on the difference between the target throttle opening and the learning throttle opening, the throttle learning value is calculated and stored in the storage area, and the target throttle opening after learning is corrected by correcting the target throttle opening based on the throttle learning value. By controlling the throttle opening according to the degree, a technique has been proposed in which the target intake air flow rate can be satisfactorily achieved with respect to variations in the throttle body and various sensors and various estimation errors.

Japanese Patent Laid-Open No. 11-229904 (paragraph 0008, FIG. 1) JP 2007-239650 A (summary column, FIG. 3)

  However, in the technology proposed in Japanese Patent Application No. 2006-231950, the throttle opening degree learning method first sets the throttle opening to the target throttle opening while fuel is injected and the intake air in the cylinder is combusted. The intake air flow rate at the time of each control is detected, the throttle learning value is calculated from the intake air flow rate, and the target throttle is corrected.

  That is, the throttle opening learning is not completed and the throttle opening region (the throttle opening corresponding to the effective opening area for which learning correction is not completed in the correspondence map between the effective opening area and the throttle opening adapted in advance) When the throttle opening is controlled and the actual intake air flow varies greatly with respect to the target intake air flow, before the target throttle correction is performed by detecting the intake air flow and calculating the throttle learning value As a result, the intake air in the cylinder is burned with a large variation in the actual intake air flow rate with respect to the target intake air flow rate, which may adversely affect drivability and the like.

  Further, the previous throttle opening learning method is carried out with respect to the throttle opening controlled according to the target intake air flow rate calculated according to the driving force request from the driver or the vehicle side. Even if the throttle opening is controlled in the throttle opening range where the opening learning has not been completed, the throttle opening learning is not performed due to the prohibition of throttle opening learning during transient operation, etc. If it is possible to travel without using the entire range, or there are many situations where the throttle opening learning is prohibited due to transient operation, etc., it takes time to complete the throttle opening learning throughout the throttle opening. There was a problem.

  The present invention has been made to solve the above-described problems, and there is a large variation in the actual intake air flow rate with respect to the target intake air flow rate until the throttle learning value is calculated and the target throttle correction is performed. An object of the present invention is to obtain a control device for an internal combustion engine that reduces the adverse effects on drivability in the state and quickly completes the throttle opening learning throughout the throttle opening.

An internal combustion engine control apparatus according to the present invention includes a throttle provided in an intake passage of an internal combustion engine, throttle opening control means for controlling the opening of the throttle and variably controlling an intake air flow rate, Atmospheric pressure detecting means or atmospheric pressure estimating means for detecting atmospheric pressure as atmospheric pressure, intake pipe internal pressure detecting means or intake pipe internal pressure estimating means for detecting pressure on the internal combustion engine side of the throttle as intake pipe internal pressure, the throttle An intake air temperature detecting means or an intake air temperature estimating means for detecting an intake air temperature on the atmosphere side of the engine, an operating state detecting means for detecting an operating state of the internal combustion engine, and a target calculated based on the operating state of the internal combustion engine The target effective opening area of the throttle opening control means is calculated based on the intake air flow rate, the atmospheric pressure, the intake pipe internal pressure, and the intake air temperature. A target throttle opening calculation for calculating a target throttle opening from the target effective opening area by using a correspondence map between the effective opening area and the throttle opening of the throttle opening control means adapted in advance and the opening area calculating means And an actual effective opening area for calculating the actual effective opening area of the throttle opening control means based on the actual intake air flow rate detected by the operating state detecting means, the atmospheric pressure, the intake pipe internal pressure, and the intake air temperature Based on the difference between the target throttle opening and the learning throttle opening, the calculating means, the learning throttle opening calculating means for calculating the learning throttle opening from the actual effective opening area using the correspondence map Throttle opening learning value calculating means for calculating the throttle opening learning value, and the target throttle opening is supplemented by the throttle opening learning value. Learning-corrected target throttle opening control means for controlling the throttle opening based on the learned post-learning target throttle opening, and throttle opening learning for each learning region according to the effective opening area axis of the corresponding map An effective opening area axis of the corresponding map in which the throttle opening learning is not completed at the time of fuel cut using the throttle opening learning execution status determining means. Is detected based on the target throttle opening calculated using the corresponding map from the effective opening area axis of the corresponding map for which the throttle opening learning has not been completed. A control device for an internal combustion engine that performs throttle opening learning by controlling the throttle opening by means of target throttle opening control means , When the actual intake air flow rate is larger than a value obtained by adding a predetermined value to the target intake air flow rate when deviating from the fuel cut condition after entering the fuel cut condition, the target effective opening area is calculated from the target intake air flow rate. And the actual intake air after the learning-corrected target throttle opening control means controls the throttle based on the target throttle opening calculated from the target effective opening area using the correspondence map. The fuel injection is resumed when the flow rate becomes equal to or less than a value obtained by adding a predetermined value to the target intake air flow rate .

  According to the control apparatus for an internal combustion engine according to the present invention, at the time of fuel cut, the throttle opening value is controlled by controlling the throttle opening to the throttle opening range where the throttle opening learning has not been completed. Until the target throttle is corrected and the intake air in the cylinder is not combusted even when there is a large variation in the actual intake air flow rate with respect to the target intake air flow rate. The adverse effect can be reduced, and the throttle opening learning can be completed quickly throughout the throttle opening.

  A preferred embodiment of a control device for an internal combustion engine according to the present invention will be described below with reference to the drawings. The present invention is not limited to the embodiments.

Embodiment 1 FIG.
1 is a block diagram for illustrating a control device for an internal combustion engine according to Embodiment 1 of the present invention. In FIG. 1, an airflow sensor 2 that measures an intake air flow rate is provided upstream of an intake system of an internal combustion engine (hereinafter referred to as an engine) 1. Further, an intake air temperature sensor 3 as an intake air temperature detecting means for measuring the intake air temperature is provided integrally with the airflow sensor 2. The intake air temperature sensor 3 may be separate from the airflow sensor 2, and a means for estimating the intake air temperature may be used instead of providing the intake air temperature sensor 3 for measuring the intake air temperature. A throttle 4 that is electronically controlled to adjust the intake air flow rate is provided on the engine 1 side downstream of the air flow sensor 2. A throttle position sensor is used to measure the opening of the throttle 4. 5 is provided.

  A surge tank 6 downstream of the throttle 4 is provided with an intake manifold pressure sensor 7 which is an intake system internal pressure detection means for measuring the internal pressure of the surge tank 6. Instead of providing the intake manifold pressure sensor 7 for measuring the intake manifold pressure, a means for estimating the intake manifold pressure may be used. Furthermore, an EGR valve 8 is connected to the surge tank 6. The engine 1 is provided with an alternator 30 as an AC generator, and the alternator 30 is configured to change the generated voltage according to a target FR duty value described later. In order to detect the engine speed, the engine 1 is provided with a crank angle sensor 31.

  FIG. 2 is a block diagram showing a control device for an internal combustion engine according to Embodiment 1 of the present invention. In FIG. 2, the intake air flow rate measured by the airflow sensor 2, the intake air temperature measured by the intake air temperature sensor 3, the opening degree of the throttle 4 measured by the throttle position sensor 5, and the intake manifold pressure sensor 7 are measured. The intake manifold pressure, the atmospheric pressure measured by the atmospheric pressure sensor 10, and the crank angle signal (used for detecting the engine speed) detected by the crank angle sensor 31 are an electronic control unit (hereinafter referred to as ECU) 9 Is input. Instead of the atmospheric pressure sensor 10 that measures the atmospheric pressure, a means for estimating the atmospheric pressure may be used. In addition, measured values are input to the ECU 9 from various sensors 55 other than the above.

  In the ECU 9, a target torque is calculated from various input data, a target intake air flow rate that achieves the calculated target torque is calculated, and the target intake air flow rate is achieved as described below so as to achieve the target intake air flow rate. The target throttle opening is obtained by calculating the effective opening area. Then, the opening degree of the throttle 4 is controlled so as to achieve the target throttle opening degree. At the same time, command values for various actuators 56 including an injector, ignition coil, or EGR valve 8 (not shown) are also calculated.

  Then, the FR duty value is input from the alternator 30 to the ECU 9. The FR duty value is an index of the power generation voltage of the alternator 30 (the power generation voltage of the alternator 30 increases as the FR duty value increases), and the power generation voltage of the alternator 30 can be detected by monitoring the FR duty value. Further, the target FR duty value is input from the ECU 9 to the alternator 30. The alternator 30 controls the generated voltage so that the FR duty value becomes equal to the target FR duty value. In addition, since the drive torque of the alternator 30 increases as the power generation voltage of the alternator 30 increases, the target FR duty value also controls the drive torque of the alternator 30.

  Next, how the target throttle opening for achieving the target intake air flow rate is calculated in the ECU 9 will be described in detail with reference to FIG. FIG. 3 is a block diagram showing a throttle control unit of the control device for an internal combustion engine according to the first embodiment of the present invention.

  The so-called throttle flow meter volume flow rate calculation formula is expressed by the following formula (1).

  Here, Qa is the target intake air flow rate, ao is the sound velocity in the atmosphere, C is the flow coefficient, At is the throttle opening area, Pe is the intake manifold pressure, Po is the atmospheric pressure, and k is the specific heat ratio.

  Further, when the dimensionless flow rate σ is defined by the following equation (2),

Expression (1) can be expressed as the following Expression (3).

  The sound velocity ao in the atmosphere is expressed by the following equation (4), where R is a gas constant and To is the intake air temperature.

  Here, when a target intake air flow rate Qa (hereinafter referred to as target Qa) necessary for achieving the target torque, a sound velocity ao in the atmosphere, and a dimensionless flow rate σ are given, a flow coefficient C and a throttle opening The effective opening area CAt represented by the product of the area At can be calculated by the following equation (5) obtained by modifying the equation (3).

  The calculation of the target effective opening area CAt (hereinafter referred to as target CAt) in the ECU 9 is performed by using the first instruction unit 11 in the block diagram shown in FIG. It is calculated as a target CAt for achieving the target Qa from the speed of sound ao and the dimensionless flow rate σ. Thus, since the target CAt is calculated based on the volumetric flow rate calculation formula of the throttle type flow meter, the target Qa can be satisfactorily set even when the engine operating state changes such as changes in environmental conditions or EGR introduction. The target CAt to be achieved can be calculated.

  By the way, it is not practical to calculate the sound speed ao in the atmosphere necessary for the calculation of the first instruction unit 11 in the ECU 9 using the equation (4) because the calculation load becomes enormous. Therefore, the second instruction unit 12 calculates the theoretical value of the sound speed ao in the atmosphere in advance and stores it as a map of the intake air temperature To in order to suppress the calculation load in the ECU 9, and the first instruction unit 11. The second instruction unit 12 calculates the sound velocity ao in the atmosphere using the intake air temperature To before the calculation.

  Further, the dimensionless flow rate σ required for the calculation of the first instruction unit 11 is not practical to calculate in the ECU 9 using the formula (2) because the calculation load becomes enormous. Therefore, in the third instruction unit 13, in order to suppress the calculation load in the ECU 9, a theoretical value of the dimensionless flow rate σ is calculated in advance and stored as a map of the pressure ratio between the intake manifold pressure Pe and the atmospheric pressure Po. Before the calculation of the first indicator 11, the fourth indicator 14 calculates the pressure ratio between the intake manifold pressure Pe and the atmospheric pressure Po, and the calculated pressure ratio between the intake manifold pressure Pe and the atmospheric pressure Po is used to calculate the third pressure. The instructing unit 13 calculates a dimensionless flow rate σ.

  By the way, it is generally known that when the pressure ratio between the intake manifold pressure Pe and the atmospheric pressure Po is less than a predetermined value 0 (about 0.528 in the case of air), the flow rate of air passing through the throttle is saturated (so-called choke). ing. It is also known that when this choke occurs, the dimensionless flow rate σ calculated by the equation (2) becomes a constant value.

  Therefore, when the pressure ratio between the intake manifold pressure Pe and the atmospheric pressure Po is equal to or less than the predetermined value 0, the fourth indicator 14 sets the pressure ratio between the intake manifold pressure Pe and the atmospheric pressure Po to the predetermined value 0, thereby causing choke. Can also handle cases. Instead of setting the pressure ratio between the intake manifold pressure Pe and the atmospheric pressure Po in the fourth instruction section 14 to a predetermined value 0, the pressure ratio between the intake manifold pressure Pe and the atmospheric pressure Po is expressed in the third instruction section 13. The map value of the dimensionless flow rate σ may be the same as that when the pressure ratio of the intake manifold pressure Pe and the atmospheric pressure Po is equal to or less than the predetermined value 0.

  Further, since the airflow sensor 2 is affected by the intake air pulsation when the pressure ratio between the intake manifold pressure Pe and the atmospheric pressure Po increases to some extent, an error may occur between the actual intake air flow rate and the measured intake air flow rate. is there. Furthermore, if the pressure ratio between the intake manifold pressure Pe and the atmospheric pressure Po increases to some extent, the dimensionless flow rate σ may also be affected by the measurement error of the intake manifold pressure Pe due to the intake air pulsation.

  Therefore, when the pressure ratio between the intake manifold pressure Pe and the atmospheric pressure Po is equal to or greater than the predetermined value 1, the fourth instruction unit 14 treats the pressure ratio between the intake manifold pressure Pe and the atmospheric pressure Po as the predetermined value 1 to thereby reduce the intake air pulsation. The influence can be reduced and the throttle controllability can be secured. Instead of setting the pressure ratio between the intake manifold pressure Pe and the atmospheric pressure Po to the predetermined value 1 in the fourth instruction section 14, the pressure ratio between the intake manifold pressure Pe and the atmospheric pressure Po is expressed in the third instruction section 13. The map value of the dimensionless flow rate σ may be the same value as the predetermined value 1 when the pressure ratio between the intake manifold pressure Pe and the atmospheric pressure Po is equal to or greater than the predetermined value 1.

  As described above, the target throttle opening is calculated by the fifth instruction unit 15 using the target CAt calculated by the first instruction unit 11. At that time, the actual effective opening area CAt (hereinafter referred to as actual CAt) calculated by the equation (5) using the throttle opening and the actual intake air flow rate Qa (hereinafter referred to as actual Qa) measured by the airflow sensor in advance. ) And is stored as a two-dimensional map in which the throttle opening and the effective opening area CAt have a one-to-one correspondence, and the target throttle opening is calculated from the target effective opening area CAt by using this map. be able to. In this way, since a two-dimensional map of the throttle opening and the effective opening area CAt can be easily created, the setting man-hours can be greatly reduced.

  When the throttle is controlled to the target throttle opening calculated as described above, the throttle opening learning is performed so as to reduce the difference between the target Qa and the actual Qa due to variations in the throttle body and various sensors and various estimation errors. A method for calculating the value will be described below.

The method for calculating the throttle opening learning value will be described in detail with reference to FIGS. 4 and 5.
Assuming that the throttle opening TP and the effective opening area CAt have a one-to-one correspondence, if there is an error between the target Qa and the actual Qa, the target CAt and the actual Qa calculated from the target Qa are expressed by the equation (5). There is also an error with the actual CAt calculated by applying to. Here, the relationship between the throttle opening TP and the effective opening area CAt previously adapted for use in control (hereinafter referred to as a CAt-TP map), the throttle body, intake manifold pressure, atmospheric pressure, Let us consider a case where there is an error as shown in FIG. 4 between the actual CAt-TP relationship calculated by a sensor for measuring the temperature or the estimation method.

  First, the sixth instruction unit 16 and the seventh instruction unit 17 in FIG. 5 use a target CAt calculated from the target Qa and a target throttle opening (hereinafter referred to as a target TP) using a CAt-TP map that is adapted in advance. ) Is calculated. The relationship between the calculated target CAt and target TP is indicated by point a in FIG. However, if there is an error in the relationship between the CAt-TP map and the actual CAt-TP, the actual Qa obtained when the throttle opening is controlled to the target TP does not match the target Qa. Therefore, in order to calculate a learning value for correcting this error, first, the actual CAt is calculated from the actual Qa by the eighth instruction unit 18 in FIG. The relationship between the actual CAt calculated here and the target TP is indicated by a point b in FIG. 4, and the point b exists on a curve indicating the actual CAt-TP relationship.

  Now, in order to achieve the target Qa, the throttle opening needs to be a point d on the curve indicating the actual CAt-TP relationship in FIG. There is a need. Therefore, as shown in FIG. 4, it is assumed that the relationship between the CAt-TP map and the actual CAt-TP is locally substantially parallel. First, the ninth instruction unit 19 in FIG. A learning throttle opening (hereinafter referred to as learning TP) is calculated using the CAt-TP map.

The relationship between the learning TP calculated here and the actual CAt is indicated by a point c in FIG. 4, and the throttle opening difference ΔTP between the target TP and the learning TP indicated between bc is the learning between a and d. The throttle learning basic value ΔTP is calculated as indicated by the tenth instruction unit 20 in FIG. Since the throttle learning basic value ΔTP calculated here varies instantaneously, the throttle learning basic value ΔTP is set to 0 as shown in the eleventh instruction unit 21 and the twelfth instruction unit 22 of FIG. The value multiplied by the correction coefficient of 1 or less is sequentially integrated, or the throttle learning basic value ΔTP is filtered to calculate the throttle learning value TP _LRN , as shown in the thirteenth instruction unit 23 in FIG. Further, a target throttle opening after learning correction is calculated by adding the throttle learning value TP _LRN to the previously calculated target TP. By controlling the throttle opening based on the target throttle opening after learning correction, the error between the target Qa and the actual Qa can be reduced.

Here, when the error in the relationship between the CAt-TP map and the actual CAt-TP has a substantially constant relationship, even when the throttle learning value TP _LRN is used alone as feedback control, it can be satisfactorily controlled in the entire operation region. As shown in FIG. 6 (a), the relationship between the CAt-TP map and the actual CAt-TP may be crossed, or as shown in FIG. If the error from CAt-TP is not constant, problems such as follow-up delay and overshoot occur during transient operation when the throttle learning value TP _LRN is used alone. Therefore, by distributing the throttle learning value _{TP LRN} and real-time learning value TP _R used as a feedback control, the long-time learning value TP _L to be stored for each learning region corresponding to CAt axis of CAt-TP map, CAt-TP can be brought close to the sum of the map value and the long-time learning value TP _L to the actual relationship between the CAt-TP, it can further absorb the instantaneous error by a feedback control by also combined real-time learning value TP _R. The above will be described in detail with reference to FIG.

In instruction 24 of the 14 distributes the throttle learning value _{TP LRN} in real-time learning value TP _R and the long time learning value TP _L at a predetermined ratio. The reset condition and update inhibiting condition of the real-time learning value TP _R to be described later if not satisfied, the instruction unit 25 of the first 15, the final real-time learning value TP _R is calculated. The update inhibiting condition of the long time learning value TP _L to be described later if not satisfied, the instruction unit 26 of the first 16, the long time learning value TP _L is calculated for each learning region.

Next, a method for calculating the long time learning value TP _L for each learning region. Referring to FIG. 4 again, as described above, the throttle learning value TP _LRN is calculated as the throttle learning basic value by calculating the throttle opening difference ΔTP between the target TP and the learning TP expressed between bc as a−. This is applied as a learning value between d. When the throttle learning value TP _LRN is distributed and stored on the CAt axis of the CAt-TP map, for example, for each learning area corresponding one-to-one, as shown in FIG. 8, the learning area corresponding to the CAt axis before and after the target CAt. If it is possible to store a long time learning value TP _L at least one of the learning regions corresponding to CAt axis before and after the actual CAt. Incidentally, the long time learning value TP _L to be stored in the learning region corresponding to each CAt axis, with respect to the previous long-time learning value TP _L, or by adding a predetermined value, CAt axis before and after the target CAt and the actual CAt It can be calculated by adding a value according to the ratio up to. Also, if storing the long-time learning value TP _L in both target CAt and the actual CAt, it is possible to shorten the convergence time of the long time learning value TP _L.

When calculating this way a long time learning value TP _L, so trainable is only when the update inhibiting condition described later is satisfied, actually the learning is performed is limited to normal use range of the steady operation. Generally, since the throttle opening and the intake air flow rate are in a monotonically increasing relationship, the relationship between the effective opening area CAt and the throttle opening TP needs to be monotonically increasing. However if the local learning is performed, as shown in FIG. 9, it can occur when the sum of the CAt-TP map value and the long-time learning value TP _L is not a monotonically increasing. In this case, for example, although the target Qa is increased, the target throttle opening after learning correction is decreased, so that problems such as a decrease in engine output and erroneous learning of the throttle learning value occur. Therefore, the process of limiting the long-time learning value TP _L so that the sum of the CAt-TP map value and the long-time learning value TP _L as shown in FIG. 9 will increase monotonically, the instruction unit 27 of the 17 in FIG. 7 By doing so, it is possible to prevent such erroneous learning and malfunction.

Details of the monotonous increase process will be described. If the long-time learning value of the current learning target is TP _L (n) (n is the CAt axis number of the current learning target, the possible range is 1 to the number of CAt axes), the long-time learning value after monotonic increase correction is It can be calculated by repeated calculation according to the following formula.
(1) CAt axis number is greater than n

Here, i is a variable that sequentially increases from 0 to the number of CAt axes− (n + 1) during repeated calculation.
(2) Area where CAt axis number is smaller than n

Here, j is a variable that sequentially increases from 0 to n−2 during repeated calculation.

After the above operations, the instruction unit 28 of the 18 in FIG. 7, stores the final long time learning value TP _L for each learning region.

Thus, if stored by distributing the throttle learning value TP _LRN in real-time learning value TP _R and the long time learning value TP _L, learning corrected target throttle opening calculated by the instruction unit 23 of the 13 of Fig. 5 used instead of the throttle learning value TP _LRN, the use of 19 correction throttle learning value obtained by adding the long time learning value TP _L corresponding to real-time learning value TP _R and operating region shown by the instruction unit 29 in FIG. 7 It becomes.

As described above, the throttle learning value TP _LRN is calculated and stored. Since such learning cannot be performed in the entire operation region, a learning prohibition process is necessary. Hereinafter, the learning prohibition condition will be described.

As described above, the airflow sensor 2 is affected by the intake air pulsation when the pressure ratio between the intake manifold pressure Pe and the atmospheric pressure Po increases to some extent, so that an error occurs between the actual intake air flow rate and the measured intake air flow rate. There is a case. In such an operation region, the throttle learning value TP _LRN cannot be accurately calculated. Therefore, the pressure ratio of the intake manifold pressure Pe and the atmospheric pressure Po is the case of one or more predetermined value mentioned above, by prohibiting the updating of the real-time learning value TP _R and the long time learning value TP _L, due to the influence of the intake air pulsation It is possible to prevent erroneous learning of throttle learning.

Next, when the target Qa changes suddenly during transient operation, etc., the calculation time delay until the target throttle opening is calculated, the response delay until the throttle opening reaches the target value, and the vicinity of the airflow sensor 2 due to the throttle opening change. A certain amount of time is required until the actual Qa responds to the change in the target Qa due to a response delay until the flow velocity changes, a response delay of the airflow sensor 2, and the like. Therefore, the elapsed time after the change rate of the target Qa becomes a predetermined value 2 or more is within a predetermined value 3 prohibits updating of the long-time learning value TP _L. Thus it is possible to prevent erroneous learning of the long time learning value TP _L due to the response delay of the actual Qa.

Further, when prohibiting updates also real-time learning value TP _R under the same conditions, e.g., across the point where the cross actual relationship CAt-TP and CAt-TP map value as shown in (a) of FIG. 6 Considering the case of change, the real-time learning value TP _R because the sign is reversed before and after the change, or an overshoot occurs, a problem time the convergence to the target Qa takes occurs. Therefore, in the condition by performing a reset process in real-time learning value TP _R, suppressing overshoot, convergence time to the target Qa is prevented from increasing.

Then, since the time of power-off in the stopping or ECU9 engine 1 not be throttle learning, real-time learning value TP _R performs reset processing. On the other hand, with respect to the long time learning value TP _L, by maintaining a backup memory, it is possible to also control to better target Qa at the next restart.

In addition, when the engine is started, the air in the vicinity of the airflow sensor 2 does not move while the engine 1 is normally consuming the air in the surge tank 6, so that the air in the vicinity of the airflow sensor 2 flows after the engine starts, A certain amount of time is required until the actual Qa can be measured accurately. Therefore, the elapsed time after the start of the engine is within a predetermined value 4 by prohibiting update of the real-time learning value TP _R, it is possible to prevent a calculation error of the real-time learning value TP _R due to the influence of the actual Qa.

Further, until the engine speed converges to the engine speed at the time of idling after the engine is started, generally, fluctuations in the engine speed and the intake air flow rate are significant, so that the throttle learning value TP _{LRN is set} to the long time learning value TP. _It is not preferable to store in _L. Therefore, the predetermined value within 5 elapsed time after the engine start is a predetermined value equal to or greater than 4 prohibits updating of the long-time learning value TP _L. Thus, it is possible to prevent erroneous learning of the long time learning value TP _L. In this case, during the elapsed time after starting the engine is a predetermined value 5 from the predetermined value 4 becomes that real-time learning value TP _R is updated, to operate as a real-time learning value TP _R is feedback control, updating of the learning value As a result, the throttle opening is controlled so as to achieve the target Qa, and an effect of preventing engine stall due to a decrease in engine speed that may occur after the engine is started is obtained.

In addition, even when the engine speed is significantly lower than the engine speed during idling immediately before the engine is stopped or due to load fluctuations, etc., since the engine speed and intake air flow rate vary greatly, the throttle learning value TP _LRN is it is not preferable to store the long time learning value TP _L. Therefore, also prohibits updating of the long-time learning value TP _L when the engine speed reaches a predetermined value 6 or less smaller than the engine rotational speed during idling. Note that real-time learning value TP _R is to operate as a feedback control, the effect of preventing the stalling by controlling the throttle opening so as to achieve the goal Qa by performing the updating of the learning value is obtained.

  A method for performing throttle opening learning by controlling the throttle opening to a throttle opening region where the throttle opening learning has not been completed at the time of fuel cut will be described below with the throttle opening learning logic as described above. To do. It should be noted that the throttle opening learning described above is performed except during fuel cut.

First, the reason why the throttle opening can be controlled to the throttle opening range where the throttle opening learning has not been completed at the time of fuel cut will be described.
When the throttle opening is changed in a normal operating state in which fuel injection is performed, the fuel injection amount is controlled in accordance with the intake air flow rate into the cylinder that changes thereby, so that the output changes greatly. Therefore, the throttle opening generally has a one-to-one correspondence with the engine speed and the target torque required by the driver, and the throttle opening cannot be controlled so freely.

  On the other hand, since the intake air in the cylinder is not burned at the time of fuel cut, the output does not change much even if the throttle opening is changed and the intake air flow rate into the cylinder is changed. Therefore, it is possible to control the throttle opening to the throttle opening range where the throttle opening learning has not been completed at the time of fuel cut. For example, when the vehicle is going down a slope and the driver is controlling the vehicle speed, if the throttle opening is increased for learning the throttle opening from a state where the throttle opening is near the fully closed position, the pump loss is reduced. Since the output is reduced and the output is slightly increased, a feeling of acceleration occurs against the driver's intention. This can be solved by adjusting the drive torque of the alternator 30 (hereinafter referred to as ALT load torque) as described later, thereby suppressing the load fluctuation of the internal combustion engine due to the pump loss fluctuation.

  Next, execution determination of throttle opening learning at the time of fuel cut will be described. As described above, the throttle opening is controlled to the throttle opening range where the throttle opening learning has not been completed at the time of fuel cut. In this embodiment, the throttle opening learning execution status determination flag map shown in FIG. 10 is used. Then, the throttle opening area where the throttle opening learning is not completed is specified.

  The throttle opening learning execution status determination flag map has a flag value for each CAt axis of the CAt-TP map. When the flag value is 0, it indicates that the throttle opening degree learning has not been completed at the throttle opening corresponding to the CAt axis, and when the flag value is 1, it indicates that the throttle opening degree learning has been performed. Yes.

In this embodiment, when the long time learning value TP _L is update inhibiting condition is not satisfied, if real-time learning value TP _R calculated by carrying out the throttle opening learning is greater than a predetermined value 7, the throttle opening learning the flag value in sufficient and not around the CAt axis target CAt at that time as is required throttle opening learning again (equal target CAt and CAt axis thereof CAt axis only) is 0, the real-time learning value TP _R Assuming that the throttle opening degree learning is completed when the value becomes equal to or less than the predetermined value 7, the flag value on the CAt axis before and after the target CAt at that time is set to 1.

Also, if storing the long-time learning value TP _L in both target CAt and the actual CAt as shown in Figure 8, it is assumed to carry out the updating of the flag value in the same manner with respect to the actual CAt. Incidentally, those updates throttle opening learning implementation determination flag map is implemented throttle opening learning is performed every time the real-time learning value TP _R is calculated (after indication portion 25 of the first 15 of FIG. 7) And In addition, the initial value of the throttle opening learning implementation status determination flag value is 0, the throttle opening learning implementation status determination flag value is held in the backup memory, and is initialized when the battery is removed. From the above, by referring to the throttle opening learning execution status determination flag map, it is possible to identify a throttle opening region where throttle opening learning has not been completed.

Next, throttle control from the time of fuel cut to the restart of fuel injection will be described using the block diagram shown in FIG.
First, when the operating state of the engine 1 enters the fuel cut execution condition, fuel injection is prohibited after the current target TP value (hereinafter referred to as TP0) is stored as indicated by the instruction unit 32 in FIG. The

  Thereafter, the processing shown in the instruction units 33 to 37 in FIG. 11 is repeated until the fuel cut execution condition is removed. The instruction unit 33 determines whether or not there is a throttle opening region for which the throttle opening learning has not been completed. If the flag value is 1 for all CAt axes with reference to the throttle opening learning execution status determination flag map, there is no throttle opening area for which the throttle opening learning has not been completed, and the process proceeds to the instruction unit 37. Otherwise, the process proceeds to the instruction unit 34.

  When the process proceeds to the instruction unit 34, the throttle opening learning is performed in the throttle opening region where the throttle opening learning has not been completed. The instructing unit 34 refers to the throttle opening learning execution status determination flag map, and CAt on the CAt axis where CAt is the smallest among the CAt axes for which the throttle opening learning has not been completed (hereinafter referred to as CAt ′). Is calculated. CAt ′ is calculated here because the throttle opening degree learning order is executed from the side where the throttle opening is small (that is, the side where CAt on the CAt axis is small). Because, in most cases, the throttle opening is more frequently used from the fully closed to the middle opening than near the fully open, so by learning the throttle opening from the side where the throttle opening is small, This is to reduce the adverse effect on drivability and the like due to incomplete throttle opening learning.

  Subsequently, the instruction unit 35 sets CAt ′ as the target CAt. The instruction unit 36 updates the instruction units 17 to 23 in FIG. 5, the instruction units 24 to 29 in FIG. 7, and the throttle opening learning execution status determination flag map based on the target CAt set by the instruction unit 35. Throttle opening learning is performed, learning corrected target throttle opening is calculated, and throttle opening is controlled.

Note that by the CAt 'target CAt, the 16th long time learning value TP _L calculated by the instruction unit 26 in FIG. 7, the ratio of up to CAt axis before and after the target CAt as shown in FIG. 8 is added to the learning region corresponding to CAt axis back and forth in a value corresponding (in this case, long time in CAt axis before and after the target CAt based on the long-time learning value TP _L at the target CAt not on CAt axis it means that estimate the learned value TP _L decreases the accuracy of the throttle opening learning) rather than because adds to the learning area that corresponds to it CAt ', to implement the more accurate throttle opening learning Become.

  On the other hand, when the operation proceeds from the instructing unit 33 to the instructing unit 37, learning of the throttle opening is completed, so the instruction unit 37 sets the target TP to TP0 and controls the throttle opening. If the conditions shown in the instruction units 33 to 37 in FIG.

  The instructing unit 38 compares the value obtained by adding the predetermined value 8 to the target Qa and the actual Qa. If the actual Qa is equal to or smaller than the value obtained by adding the predetermined value 8 to the target Qa, the instruction unit 38 proceeds to instruct the fuel injection. Resume. On the other hand, for example, since the throttle opening learning is performed in the instruction unit 38 when the throttle opening is large at the time of fuel cut, the actual Qa becomes larger when the fuel cut condition is not satisfied. If the value is larger than the value obtained by adding the predetermined value 8, the actual Qa is equal to or less than the value obtained by adding the predetermined value 8 to the target Qa because the engine speed may rise more than the driver requests if the fuel injection is resumed. The processing of the instruction units 39 and 40 is looped until The instruction unit 39 calculates the target CAt from the target Qa by the same process as that of the first instruction unit 11 in FIG.

  The instruction unit 40 performs the same processing as the instruction unit 36 and controls the throttle opening so that the actual Qa matches the target Qa. If the actual Qa is equal to or less than the value obtained by adding the predetermined value 8 to the target Qa during the processing of the instruction units 39 and 40, the process proceeds to the instruction unit 41. It should be noted that the value of the predetermined value 8 may be increased if importance is placed on quick resumption of fuel injection in the instructing unit 41 rather than prevention of the engine speed from blowing up, and a predetermined value if the engine speed is more important in preventing the engine speed from rising. What is necessary is just to make the value of 8 small.

  With the above control, the throttle opening degree learning can be performed by controlling the throttle opening degree to the throttle opening range where the throttle opening degree learning is not completed at the time of fuel cut.

  By the way, as described above, there is a problem in that the pump loss fluctuates and the load of the internal combustion engine is changed by controlling the throttle opening to the throttle opening region where the throttle opening learning has not been completed at the time of fuel cut. On the other hand, this problem is solved by adjusting the ALT load torque in addition to the throttle control.

  First, a map group used for adjusting the ALT load torque will be described. FIG. 12 shows an ALT load torque map. This has the engine speed and the FR duty value as parameters and the ALT load torque as a map value, and the map value is set in advance by an actual machine test or the like. Thereby, the ALT load torque can be calculated from the engine speed and the FR duty value.

  FIG. 13 shows a target FR duty map. This has the engine speed and the desired ALT load torque (hereinafter referred to as the target ALT load torque) as parameters and the target FR duty value as a map value. The map value is set in advance by an actual machine test or the like. To do. Thereby, the target FR duty value can be calculated from the engine speed and the target ALT load torque.

  FIG. 14 shows a pump loss map. This has engine speed and intake manifold pressure as parameters and pump loss as a map value, and the map value is set in advance by an actual machine test or the like. Thereby, the pump loss can be calculated from the engine speed and the intake manifold pressure.

Next, alternator control from the time of fuel cut to the restart of fuel injection will be described using the block diagram shown in FIG.
First, when the operation state of the engine 1 enters the fuel cut execution condition, the engine speed is detected by the instruction unit 42, and the intake manifold pressure is detected by the instruction unit 43. The instruction unit 44 calculates the pump loss Pp0 using the pump loss map, the engine speed detected by the instruction unit 42, and the intake manifold pressure detected by the instruction unit 43. Then, the instruction unit 45 calculates the ALT load torque Talt0 using the ALT load torque map, the engine speed detected by the instruction unit 42, and the FR duty value input from the alternator 30 to the ECU 9.

  The processing of the instruction units 42 to 45 is performed after the processing of the instruction unit 32 in FIG. 11 and before the processing of the instruction unit 33 is performed. Thereafter, the processing shown in the instruction units 46 to 51 in FIG. 15 is repeated until the fuel cut execution condition is removed. The instruction unit 46 detects the engine speed, and the instruction unit 47 detects the intake manifold pressure. The instruction unit 48 calculates the pump loss Pp using the pump loss map, the engine speed detected by the instruction unit 46, and the intake manifold pressure detected by the instruction unit 47. Then, the instruction unit 49 calculates a pump loss fluctuation Pp ′ (= Pp0−Pp) from the pump loss Pp0 calculated by the instruction unit 44 and the pump loss Pp calculated by the instruction unit 48.

  The instruction unit 50 calculates the target ALT load torque Talt (= Talt0 + Kp × Pp ′) from the ALT load torque Talt0 calculated by the instruction unit 45 and the pump loss fluctuation Pp ′ calculated by the instruction unit 49. The coefficient Kp is a pump loss-torque conversion coefficient. For example, when the unit of the ALT load torque Talt0 is (Nm) and the unit of the pump loss fluctuation Pp ′ is (kPa) (average effective pressure), Kp = (Vs '× z) / 4π (where Vs' is the displacement per cylinder (L) and z is the number of cylinders).

  The instruction unit 51 calculates a target FR duty value using the target FR duty map, the engine speed detected by the instruction unit 46, and the target ALT load torque Talt calculated by the instruction unit 50, and transmits the target FR duty value to the alternator 30. When the target ALT load torque Talt cannot be satisfied even when the target FR duty value is maximized or minimized, such as when the target ALT load torque Talt is larger than the ALT load torque when the target FR duty value is maximized. The target FR duty value that minimizes the difference between the ALT load torque at the target FR duty value and the target ALT load torque Talt is calculated and transmitted to the alternator 30.

  Then, during the process shown in the instruction units 46 to 51 of FIG. In the instructing unit 52, if the fuel injection is resumed, the alternator control from the time of the fuel cut until the fuel injection is resumed, and the normal alternator control is performed. If the fuel injection has not been resumed, the process proceeds to the instructing unit 53. The instruction unit 53 detects the engine speed. Then, the instruction unit 54 calculates a target FR duty value that minimizes the target ALT load torque using the target FR duty map and the engine speed detected by the instruction unit 53, and transmits the target FR duty value to the alternator 30.

  Here, the reason why the alternator 30 is controlled so as to minimize the target ALT load torque is as follows. The case where the fuel cut execution condition is deviated after entering the fuel cut execution condition is a case where a torque larger than the current state is required, for example, when the driver depresses the accelerator. However, as indicated by the instruction units 38 to 40 in FIG. 11, when the actual Qa is larger than the target Qa, if the fuel injection is resumed as it is, the engine speed will increase more than required by the driver. Control is performed so that fuel injection does not resume until the target Qa or less is reached. In such a case, until the fuel injection is restarted, the engine output shaft torque does not increase even though a larger engine output shaft torque is required than the current state. Therefore, the engine output shaft torque is somewhat increased by reducing the load of the internal combustion engine by minimizing the ALT load torque by the instruction unit 54 until the fuel injection is restarted.

  With the above control, when the throttle opening is controlled to the throttle opening range where the throttle opening learning is not completed at the time of fuel cut and the throttle opening learning is performed, the pump loss fluctuates and the load fluctuation of the internal combustion engine is changed. Can solve problems that arise.

  As described above, according to the control apparatus for an internal combustion engine according to the first embodiment, the throttle provided in the intake passage of the internal combustion engine and the opening of the throttle are controlled, and the intake air flow rate is variably controlled. Throttle opening control means, atmospheric pressure detection means or atmospheric pressure estimation means for detecting the pressure on the atmosphere side of the throttle as atmospheric pressure, intake pipe internal pressure detection for detecting the pressure on the internal combustion engine side of the throttle as intake pipe internal pressure Or an intake pipe internal pressure estimating means, an intake air temperature detecting means for detecting the intake air temperature on the atmosphere side of the throttle or an intake air temperature estimating means, an operating state detecting means for detecting an operating state of the internal combustion engine, and the internal combustion engine Based on the target intake air flow rate calculated based on the operating state of the engine, the atmospheric pressure, the intake pipe internal pressure, and the intake air temperature, the throttle opening control means The target effective opening area is calculated from the target effective opening area using the target effective opening area calculating means for calculating the effective opening area and a correspondence map between the effective opening area and the throttle opening of the throttle opening control means adapted in advance. Target throttle opening calculating means for calculating the actual throttle opening of the throttle opening control means based on the actual intake air flow rate detected by the operating state detecting means, the atmospheric pressure, the intake pipe internal pressure, and the intake air temperature Actual effective opening area calculating means for calculating an area, learning throttle opening calculating means for calculating a learning throttle opening from the actual effective opening area using the correspondence map, the target throttle opening and the learning A throttle opening learning value calculating means for calculating a throttle opening learning value based on a deviation of the throttle opening for the engine, and the target throttle opening A learning-corrected target throttle opening control means for controlling the throttle opening based on the corrected target throttle opening corrected by the throttle opening learning value, and for each learning region corresponding to the effective opening area axis of the corresponding map Throttle opening learning execution status determining means for determining the throttle opening learning execution status of the throttle opening learning learning status using the throttle opening learning execution status determining means, and the throttle opening learning is not completed at the time of fuel cut. When the learning region corresponding to the effective opening area axis of the correspondence map is detected, the target throttle opening calculated using the correspondence map from the effective opening area axis of the correspondence map for which the throttle opening learning has not been completed is calculated. Based on the learning corrected target throttle opening control means, the throttle opening is controlled by controlling the throttle opening. As a result, the intake air in the cylinder is combusted even when the actual intake air flow rate Qa varies greatly from the target intake air flow rate Qa until the throttle learning value is calculated at the time of fuel cut and the target throttle is corrected. Because it does not, the adverse effect on drivability etc. can be reduced, and the throttle opening is controlled to the throttle opening range where the throttle opening learning is not completed, and the throttle opening learning is performed quickly so that the entire throttle opening can be obtained. The throttle opening learning can be completed.

  Further, when the actual intake air flow rate is larger than the target intake air flow rate plus a predetermined value 8 when the fuel cut condition is deviated after entering the fuel cut condition, the target intake air flow rate is compared with the target intake air flow rate. After the effective opening area is calculated and the throttle is controlled by the target throttle opening control means after learning correction based on the target throttle opening calculated from the target effective opening area using the correspondence map, When the intake air flow rate becomes equal to or less than the target intake air flow rate plus the predetermined value 8, fuel injection is restarted, for example, because the throttle opening learning is performed at a large throttle opening during fuel cut. When the actual intake air flow rate Qa becomes larger than the target intake air flow rate Qa when the fuel cut condition is not met, Driver can be prevented from blown up the engine speed to more than requires.

In addition, when there is a plurality of effective opening area axes of the corresponding map in which the throttle opening learning is not completed at the time of fuel cut, the corresponding map is used from the effective opening area axis having the smallest effective opening area among them. By setting the calculated throttle opening as the target throttle opening, in most cases the throttle opening is used more frequently than the throttle opening near the fully open position. by carrying out the opening learning, it is possible to reduce the adverse effect on drivability and the like due to the throttle opening learning is not completed, the long-time learning value TP _L by the target CAt further CAt ', 8 Instead of adding a value corresponding to the ratio of the target CAt to the CAt axis before and after the target CAt to the learning region corresponding to the front and rear CAt axes. Since adding the learning area that corresponds to it CAt ', it can be carried out more accurate throttle opening learning.

  Further, during fuel cut, when the throttle opening degree learning is performed by controlling the throttle opening degree, the power generation of the internal combustion engine is performed according to the fluctuation of the pump loss due to the change in the intake air flow rate, the engine speed, etc. By adjusting the driving torque of the engine, the load fluctuation of the internal combustion engine is suppressed and the throttle opening learning is performed, so that the throttle opening is controlled to the throttle opening range where the throttle opening learning is not completed at the time of fuel cut. This problem can be solved by adjusting the driving torque of the generator to suppress the load fluctuation of the internal combustion engine.

It is a block diagram for demonstrating the control apparatus of the internal combustion engine which concerns on Embodiment 1 of this invention. 1 is a block diagram showing an internal combustion engine control apparatus according to Embodiment 1 of the present invention. FIG. It is a block diagram which shows the throttle control part of the control apparatus of the internal combustion engine which concerns on Embodiment 1 of this invention. It is a figure which shows roughly the calculation method of the throttle learning value which concerns on Embodiment 1 of this invention. It is a figure which shows roughly the calculation method of the throttle learning value which concerns on Embodiment 1 of this invention. It is a figure which shows the pattern of the relationship between the CAt-TP map which concerns on Embodiment 1 of this invention, and actual CAt-TP. It is a figure which shows roughly the storage method of the long time learning value which concerns on Embodiment 1 of this invention. It is a figure which shows roughly the storage method of the long time learning value which concerns on Embodiment 1 of this invention. It is a figure which shows roughly the monotonous increase process of the long time learning value which concerns on Embodiment 1 of this invention. It is a figure which shows roughly the throttle opening learning implementation condition determination flag map which concerns on Embodiment 1 of this invention. It is a block diagram which shows the throttle control part from the time of fuel cut which concerns on Embodiment 1 of this invention to fuel injection restart. It is a figure which shows schematically the ALT load torque map which concerns on Embodiment 1 of this invention. It is a figure which shows roughly the target FR duty map which concerns on Embodiment 1 of this invention. It is a figure which shows roughly the pump loss map which concerns on Embodiment 1 of this invention. It is a block diagram which shows the alternator control part from the time of the fuel cut which concerns on Embodiment 1 of this invention to fuel injection restart.

Explanation of symbols

1 engine (internal combustion engine)
2 Airflow sensor 3 Intake air temperature sensor 4 Throttle 5 Throttle position sensor 6 Surge tank 7 Intake manifold pressure sensor 8 EGR valve 9 ECU
DESCRIPTION OF SYMBOLS 10 Atmospheric pressure sensor 11 1st instruction | indication part 12 2nd instruction | indication part 13 3rd instruction | indication part 14 4th instruction | indication part 15 5th instruction | indication part 16 6th instruction | indication part 17 7th instruction | indication part 18 8th Instruction unit 19 Ninth instruction unit 20 10th instruction unit 21 11th instruction unit 22 12th instruction unit 23 13th instruction unit 24 14th instruction unit 25 15th instruction unit 26 16th instruction unit 27 17th instruction section 28 18th instruction section 29 19th instruction section 30 Alternator 31 Crank angle sensors 32-54 Instruction section 55 Various sensors 56 Various actuators

Claims (3)

A throttle provided in the intake passage of the internal combustion engine;
Throttle opening control means for controlling the throttle opening and variably controlling the intake air flow rate;
An atmospheric pressure detecting means or an atmospheric pressure estimating means for detecting the pressure on the atmosphere side of the throttle as an atmospheric pressure, an intake pipe internal pressure detecting means or an intake pipe internal pressure estimating means for detecting the pressure on the internal combustion engine side of the throttle as an intake pipe internal pressure An intake air temperature detecting means or an intake air temperature estimating means for detecting an intake air temperature on the atmosphere side of the throttle, and an operating state detecting means for detecting an operating state of the internal combustion engine,
Target effective opening area for calculating the target effective opening area of the throttle opening control means based on the target intake air flow rate calculated based on the operating state of the internal combustion engine, the atmospheric pressure, the intake pipe internal pressure, and the intake air temperature A calculation means;
A target throttle opening calculating means for calculating a target throttle opening from the target effective opening area using a correspondence map between the effective opening area of the throttle opening control means and the throttle opening adapted in advance;
Actual effective opening area calculating means for calculating an actual effective opening area of the throttle opening control means based on the actual intake air flow rate detected by the operating state detecting means, the atmospheric pressure, the intake pipe internal pressure, and the intake air temperature; ,
A learning throttle opening calculating means for calculating a learning throttle opening from the actual effective opening area using the correspondence map;
Throttle opening learning value calculation means for calculating a throttle opening learning value based on a deviation between the target throttle opening and the learning throttle opening;
Learning-corrected target throttle opening control means for controlling the throttle opening based on the corrected target throttle opening obtained by correcting the target throttle opening based on the throttle opening learning value;
Throttle opening learning implementation status determination means for determining the implementation status of throttle opening learning for each learning area according to the effective opening area axis of the correspondence map,
When the learning area corresponding to the effective opening area axis of the correspondence map in which the throttle opening learning has not been completed is detected at the time of fuel cut using the throttle opening learning execution status determination means, the throttle opening learning is performed. Based on the target throttle opening calculated using the correspondence map from the effective opening area axis of the correspondence map that has not been completed, the throttle opening is controlled by the learning corrected target throttle opening control means. A control device for an internal combustion engine that performs throttle opening learning ,
When the actual intake air flow rate is larger than a value obtained by adding a predetermined value to the target intake air flow rate when deviating from the fuel cut condition after entering the fuel cut condition, the target effective opening area is calculated from the target intake air flow rate. And the actual intake air after the learning-corrected target throttle opening control means controls the throttle based on the target throttle opening calculated from the target effective opening area using the correspondence map. A control apparatus for an internal combustion engine , wherein fuel injection is resumed when a flow rate becomes equal to or less than a value obtained by adding a predetermined value to the target intake air flow rate . When there are multiple effective opening area axes of the corresponding map for which the throttle opening learning has not been completed at the time of fuel cut, calculation is performed using the corresponding map from the effective opening area axis with the smallest effective opening area among them. 2. The control apparatus for an internal combustion engine according to claim 1, wherein the throttle opening to be made is the target throttle opening . During fuel cut, when the throttle opening degree learning is performed by controlling the opening degree of the throttle, the generator of the internal combustion engine is changed according to the fluctuation of the pump loss due to the change of the intake air flow rate, the engine speed, etc. The control device for an internal combustion engine according to claim 1 or 2 , wherein a load variation of the internal combustion engine is suppressed by adjusting a driving torque, and throttle opening degree learning is performed .

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