JP4321429B2 - Engine control device - Google Patents

Description

  The present invention relates to an engine control device.

A cylinder air amount equivalent injection amount Tp [ms], which is an injection amount for obtaining the theoretical air-fuel ratio (14.7) with respect to the cylinder air amount Qc [g / cycle] per cycle, is calculated, and this cylinder air amount equivalent An injection amount obtained by advancing the injection amount Tp by 10 ms is defined as a 10 ms pre-injection injection amount, and fuel of this 10 ms pre-injection injection amount is supplied to the engine from a fuel injection valve (see Patent Document 1).
JP-A-1-305144

  FIGS. 3 and 4 show changes in the cylinder air amount equivalent injection amount Tp and the 10 ms advance injection amount when the intake throttle valve opening TVO is increased by acceleration. 3 and 4, the engine rotation speed Ne is constant (for example, a predetermined rotation speed N0), and the synchronous injection timing IT is a time t2 slightly delayed from the time t1. From time t3 to time t6 is an intake valve opening period. The synchronized injection timing IT is synchronized with the crank angle, and is usually before the intake stroke as shown in the figure.

  Now, the cylinder air amount (not shown) is determined at time t6 which is the intake valve closing timing IVC. Confirming means that the air amount Qc1 is confined in one cylinder. Therefore, in order to obtain the target air-fuel ratio at this time, it is necessary to give the injection amount Tf1 corresponding to the cylinder air amount Qc1 at the synchronous injection timing at time t2. That is, the required injection amount is a waveform passing through the point (t2, Tf1), and the response waveform itself of the required injection amount is the cylinder air amount equivalent injection amount Tp (the response phase of Tp is the response of the cylinder air amount). Therefore, the response waveform obtained by advancing the response phase of the cylinder air amount equivalent injection amount Tp to the illustrated position becomes the response waveform of the required injection amount (FIGS. 3 and 4). (See dashed line).

  However, since the response waveform of the 10 ms advance injection amount is not in time for the response waveform of the required injection amount, the actual air-fuel ratio temporarily becomes lean (FIG. 4D).

  In particular, since lean misfire during rapid acceleration cannot be left unattended, interrupt injection is performed after synchronous injection timing IT to prevent lean misfire as shown in FIG. Since there is essentially no correlation between the two, the introduction of interrupt injection during rapid acceleration can prevent leaning at the initial stage of acceleration as shown by the solid line in FIG. On the contrary, it is richer (that is, the calculation accuracy of the injection amount is insufficient).

  In addition, it has been seasoned by adding wall flow correction from the past, but at this time it is difficult to avoid overcorrection in the latter half of the acceleration as shown by the one-dot chain line in FIG. There is.

  In this way, the current system is the limit so far, and it is not at a level that causes great dissatisfaction with the operability and exhaust purification level at the time of transition, but considering the recent trends in operability and exhaust regulations, further transients Improvements in operability and exhaust purification levels are required.

  The present invention has been made paying attention to such problems, and has an object to newly propose a control device for an engine different from the conventional device.

  The present invention solves the above problems by the following means. In addition, in order to make an understanding easy, although the code | symbol corresponding to embodiment of this invention is attached | subjected, it is not limited to this.

The present invention includes an accelerator opening detecting means (42) for detecting the depression amount of the accelerator pedal (41) as an accelerator opening APO, and the accelerator opening APO that is not mechanically connected to the accelerator pedal (41). with target opening value is determined intake throttle valve in accordance with, the actual intake throttle valve apparatus intake throttle valve opening has a predetermined response delay T2 until matching the intake throttle valve target value (22), wherein The throttle valve opening degree detecting means (36) for detecting the actual intake throttle valve opening degree ATVO, the air flow rate detecting means (32) for detecting the air flow rate Qa upstream of the intake throttle valve, and the accelerator opening degree APO. to multiplying the ratio AAPO / ATVO of the determined throttle valve prefetch area AAPO and the actual throttle valve area ATVO defined by opening TVO of the intake throttle valve in the air flow rate Qa Intake throttle valve ahead flow rate calculating means for calculating the intake throttle valve prefetch flow Qaa a value advanced until it coincides with the phase at which the air flow rate Qa is the accelerator opening APO phase responds when responding I ( 58), an accelerator opening equivalent cylinder air amount calculating means (59, 60) for calculating an accelerator opening equivalent cylinder air amount Qca per cycle based on the intake throttle valve pre-emptive flow rate Qaa, and this one cycle An accelerator opening equivalent injection amount calculating means (61) for calculating an accelerator opening equivalent injection amount Tca that obtains a theoretical air-fuel ratio based on the hitting accelerator opening equivalent cylinder air amount Qca, and this accelerator opening equivalent injection amount Tca. Predetermined dead time for obtaining the target air-fuel ratio with the cylinder air amount corresponding to the accelerator opening per cycle determined at the intake valve closing timing The required injection amount calculating means for calculating a value which is delayed by one as required injection amount Tpf (6 1), and fuel injection control means (31) using the required injection amount Tpf the fuel injection control, and characterized in that it comprises To do.

According to the present invention, the air flow rate Qa is multiplied by the ratio AAPO / ATVO of the intake throttle valve leading area AAPO determined by the accelerator opening APO and the throttle valve area ATVO determined by the actual intake throttle valve opening TVO. An intake throttle valve preemptive flow rate Qaa, which is a value advanced until the phase when the air flow rate Qa responds matches the phase when the accelerator opening APO responds, is calculated, and based on the intake throttle valve preemptive flow rate Qaa. An accelerator opening equivalent cylinder air amount Qca per cycle is calculated, and an accelerator opening equivalent injection amount Tca for obtaining a theoretical air-fuel ratio is calculated based on the accelerator opening equivalent cylinder air amount Qca per cycle. Cylinder air amount corresponding to accelerator opening per cycle for determining the injection amount Tca at the intake valve closing timing Calculates a value obtained by delaying a predetermined dead time T1 for obtaining the target air-fuel ratio as the required injection amount Tpf, was the required injection amount Tpf as used in the fuel injection control. As a result, the required injection amount Tpf can be given during the transition (acceleration or deceleration) without a delay in response compared to the conventional case, and the air-fuel ratio control accuracy during the transition is improved, thereby improving the transition time. The response, exhaust performance and fuel consumption can be improved.

  Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings.

  FIG. 1 is a schematic configuration diagram showing an embodiment of the present invention.

  The air metered by the intake throttle valve 23 is stored in the intake collector 2 and then introduced into the combustion chamber 5 of each cylinder via the intake manifold 3. The fuel is intermittently injected and supplied into the intake port 4 from the fuel injection valve 21 arranged in the intake port 4 of each cylinder at a predetermined timing. Here, the fuel injection amount given to the fuel injection valve 21 is based on the intake air flow rate detected by the air flow meter 32 (air flow rate detection means) by the engine controller 31 and the signal from the crank angle sensors (33, 34). It is calculated according to the calculated engine speed.

  The injected fuel is mixed with the intake air to form an air-fuel mixture. The air-fuel mixture is closed in the combustion chamber 5 by closing the intake valve 15, compressed by the ascending piston 6, and ignited by the spark plug 14 to burn. To do. The gas pressure due to the combustion works to push down the piston 6, and the reciprocating motion of the piston 6 is converted into the rotational motion of the crankshaft 7. The combusted gas (exhaust gas) is discharged into the exhaust passage 8 when the exhaust valve 16 is opened.

The exhaust passage 8 includes three-way catalysts 9 and 10. The three-way catalysts 9, 10 can efficiently remove HC, CO and NOx contained in the exhaust gas simultaneously when the air-fuel ratio of the exhaust gas is in a narrow range centered on the stoichiometric air-fuel ratio. For this reason, the engine controller 31 determines the basic injection amount from the fuel injection valve 21 according to the operating conditions, and feedback-controls the air-fuel ratio based on the signal from the O ₂ sensor 35 provided upstream of the three-way catalyst 9. .

  The intake throttle valve 23 is driven by a throttle motor 24. The driver's required torque appears in the amount of depression of the accelerator pedal 41 (accelerator opening). Therefore, the engine controller 31 determines a target torque based on a signal from the accelerator sensor 42 (accelerator opening detecting means), determines a target air amount for realizing the target torque, and obtains this target air amount. The opening degree of the intake throttle valve 23 is controlled via the throttle motor 24.

  Here, the intake throttle valve device 22 composed of the intake throttle valve 23 and the throttle motor 24 is not mechanically connected to the accelerator pedal 41 and the target value of the intake throttle valve opening is determined according to the accelerator opening. In addition, there is a predetermined response delay until the intake throttle valve opening coincides with the intake throttle valve target value.

  A variable valve mechanism (hereinafter referred to as “VEL mechanism”) 26 configured by a multi-joint link mechanism that continuously and variably controls the lift amount and operating angle of the intake valve 15, the crankshaft 7, and the intake valve cam A variable valve timing mechanism (hereinafter referred to as “VTC mechanism”) 27 is provided that continuously and variably controls the rotational phase difference with the shaft 25 to advance or retard the valve timing of the intake valve 15. Since these specific configurations are known from Japanese Patent Laid-Open No. 2003-314347, detailed description thereof is omitted.

  FIG. 2 shows a response waveform during acceleration, specifically, when the accelerator opening APO is increased from the first opening APO1 to the second opening APO2 at time t1 and the second opening APO2 is maintained. FIG. At this time, since there is a response delay in the intake throttle valve device 22, the intake throttle valve opening TVO finally increases at time t4. Even if the intake throttle valve opening TVO increases and the flow rate of air flowing downstream of the intake throttle valve 23 increases, the increased air is temporarily stored in the collector 2 and then sucked into the combustion chamber 5 (cylinder). The amount of air actually sucked into one cylinder (this amount of air is hereinafter referred to as “cylinder air amount”) Qc rises at time t5 which is further delayed from time t4.

  In the present invention, only the phase shift between the response of the injection amount and the response of the air amount at the time of transition, for example, acceleration, is a problem. Therefore, in FIG. 2, the injection amount and the air amount are aligned at the same height. When the stoichiometric air-fuel ratio is set as the target air-fuel ratio, the injection amount is actually 1 but the air amount is required to be 14.7 times. Therefore, the injection amount is originally increased from 10 to 13, for example, during acceleration. When it increases, the air amount increases by 14.7 × 3 from 14.7 × 10 to 14.7 × 13, but in FIG. 2, the injection amount expands by 14.7 times in the vertical axis direction. Therefore, when the injection amount increases by 3 from 10 to 13 as described above during acceleration, the air amount also increases by 3 from 10 to 13. The unit of the cylinder air amount Qc is [g / cycle], and the unit of the required injection amount Tpf is [ms], which is not the same, but the difference between these units is ignored. In this way, the response waveforms of the injection amount and the air amount are only shifted in the time axis direction, and will be exactly overlapped when they are translated. In other words, in FIG. 2, if the cylinder air amount Qc is 1 and the required injection amount Tpf is set to 1, the target air-fuel ratio can be obtained.

  Now, the basic concept of the fuel injection control of the present invention is as follows. That is, in the case of the intake throttle valve device 22, the throttle valve opening TVO with respect to the accelerator opening APO is delayed in response from time t1 to time t4, and actually a dead time T2 of about 40 to 50 ms occurs. That is, if the accelerator opening APO is used for the calculation of the fuel injection amount, the response of the required injection amount preceding the response phase of the intake throttle valve opening TVO can be realized. For this purpose, a value obtained by advancing the cylinder air amount Qc is calculated as an accelerator opening equivalent cylinder air amount Qca until the phase when the cylinder air amount Qc responds matches the phase when the accelerator opening APO responds. A delay process for synchronizing the accelerator opening equivalent cylinder air amount Qca with the required injection amount Tpf, that is, a delay process for the dead time T1 in the figure, is performed to calculate the required injection amount Tpf indicated by a broken line.

  In FIG. 2, it is assumed that the engine rotational speed Ne is constant (for example, a predetermined rotational speed N0), and the synchronous injection timing IT is at a time t2 slightly delayed from the time t1. From time t3 to time t6 is an intake valve opening period. The synchronized injection timing IT is synchronized with the crank angle, and usually comes before the intake stroke as shown in the figure.

  The cylinder air amount is determined at time t6, which is the intake valve closing timing IVC. Confirming means that the air amount Qc1 is confined in one cylinder. Therefore, in order to obtain the target air-fuel ratio at this time, it is necessary to give the same injection amount Tpf1 as the cylinder air amount Qc1 at the synchronous injection timing at time t2. This means that the required injection amount Tpf is a response waveform that passes through the point (t2, Tpf1), and the response waveform of the required injection amount Tpf itself is exactly the same as the response waveform of the cylinder opening equivalent cylinder air amount Qca. Therefore, a response waveform obtained by delaying the response phase of the accelerator opening equivalent cylinder air amount Qca by a predetermined dead time T1 is set as a response waveform of the required injection amount Tpf.

  Since the horizontal axis in FIG. 2 is the time axis, the synchronous injection timing IT changes when the engine rotational speed Ne becomes higher or lower than the predetermined rotational speed N0. When the engine rotational speed Ne becomes lower than the predetermined rotational speed N0, the synchronous injection timing IT is delayed from the position shown in the figure (moves to the right in the figure), and conversely when the engine rotational speed Ne becomes higher than the predetermined rotational speed N0. The injection timing IT is earlier than the illustrated position (moves to the left in the figure). In other words, since the dead time T1 varies depending on the engine speed Ne, the dead time T1 needs to be determined according to the engine speed Ne.

  Note that the range in which the synchronized injection timing IT can move in FIG. 2 is assumed to coincide with the time t1 toward the advance side (left side in the figure). If the synchronous injection timing IT advances beyond the time t1, it is not considered for the time being.

  For comparison, the current fuel injection control is shown in FIGS. 3 and 4 are considered under the same operating conditions as FIG. However, in FIG. 3 (C) and FIG. 4 (C), the response waveforms are all injection amounts, unlike FIG.

  3 and 4, the cylinder air amount equivalent injection amount Tp [ms] is calculated by the following equation using the cylinder air amount Qc [mg / cycle] per cycle.

Tp = (Qc / 14.7) × K1 (Supplement 1)
However, K1; a coefficient (a constant value) for converting the air amount into the synchronous injection pulse width.

  That is, the cylinder air amount equivalent injection amount Tp is an injection amount for obtaining the theoretical air-fuel ratio (14.7) with respect to the cylinder air amount Qc per cycle. At present, a response waveform obtained by advancing the cylinder air amount equivalent injection amount Tp by 10 ms is made to be a 10 ms advance injection amount, and the fuel of the 10 ms advance injection amount is supplied from the fuel injection valve 21 to the engine.

  However, even with this 10 ms advance injection amount, when the synchronized injection timing IT is at the same position as in FIG. 2, the actual air-fuel ratio becomes lean during acceleration because the response waveform of the required injection amount is not in time (see the broken line in FIG. 4D). ).

  In particular, since lean misfire during rapid acceleration cannot be left unattended, interrupt injection is performed after the synchronous injection timing IT as shown in FIG. 4 so that lean misfire does not occur. However, since there is essentially no correlation between the amount of interrupt injection and the degree of sudden acceleration, if interrupt injection at the time of sudden acceleration is introduced, acceleration is performed as shown by the solid line in FIG. Although the initial leaning can be prevented, it becomes rich on the late stage of acceleration (that is, the calculation accuracy of the injection amount is insufficient).

  In addition, it has been seasoned by adding a wall flow correction (correction by a transient correction amount Kathos in equation (11) described later), but at this time, as indicated by a one-dot chain line in FIG. It is difficult to avoid overcorrection in the second half of acceleration, and there is a limit to wall flow correction.

  In this way, the current system is the limit so far, and it is not at a level that causes great dissatisfaction with transient operability and exhaust purification level, but considering the recent operability and trends in exhaust regulations, further transient operation Therefore, the fuel injection control different from the conventional device is newly proposed this time.

  Details of the new fuel injection control executed by the engine controller 31 will be described based on the following block diagram. However, although this embodiment is provided with the variable valve apparatus (VEL mechanism 26 and VTC mechanism 27), it demonstrates by the case where a variable valve apparatus is not provided first, and mentions the case where a variable valve apparatus is provided after that. To do.

  5 and 6 are control block diagrams of two embodiments, FIG. 7 is a partial detailed block diagram of FIGS. 5 and 6, FIG. 8 is a partial detailed block diagram of FIG. 6 only, and FIG. 9 is two embodiments. It is a wave form diagram which shows the response at the time of acceleration common to. The embodiment shown in FIG. 5 and FIG. 7 and the embodiment shown in FIG. 6, FIG. 7, and FIG. 8 have a substantially equivalent configuration, and any one of the embodiments may be adopted according to demand. Here, FIGS. 5 and 7 are distinguished as the first embodiment, and FIGS. 6, 7 and 8 are distinguished as the second embodiment. The parts common to the two embodiments will be described first, and the second embodiment will be described. Differences from the first embodiment will be mainly described.

  FIGS. 5 and 6 of the first and second embodiments are for calculating the required injection amount Tpf [ms], the fuel injection amount Ti [ms] and the cylinder air amount equivalent injection amount Tp [ms]. It is repeatedly executed every time Δt (for example, every 1 ms).

  5 and 6, the AFM output delay / advance compensation unit 51 receives a signal from the air flow meter 32 and performs response delay / advance compensation to obtain the air flow meter flow rate Qa [kg / h]. However, here, 1/3600 is multiplied and the unit of flow rate is [g / ms]. Since the method for compensating for the lag / lead of the air flow meter output is detailed in Japanese Patent Application Laid-Open No. 2003-314347, the description thereof is omitted.

The accelerator area calculation unit 52 obtains an accelerator area AAPO [m ² ] as an intake throttle valve advance area by searching the table shown in FIG. 10 from the accelerator opening APO detected by the accelerator sensor 42. The throttle valve area calculation unit 53 obtains the throttle valve area ATVO [m ² ] by searching the table shown in FIG. 11 from the opening degree TVO of the intake throttle valve 23 detected by the throttle sensor 36. The area ratio calculator 54 calculates the ratio AAPO / ATVO between the accelerator area AAPO and the throttle valve area ATVO.

  Here, the accelerator area AAPO is a virtual area determined by the accelerator opening APO. The throttle valve area ATVO is a virtual area determined by the opening degree TVO of the intake throttle valve. The accelerator area AAPO is set to correspond to the throttle valve area ATVO on a one-to-one basis. That is, in FIGS. 10 and 11, the maximum value of the accelerator opening APO is equal to the maximum value of the intake throttle valve opening TVO, and the maximum value of the accelerator area AAPO is equal to the maximum value of the intake throttle valve area ATVO. Therefore, the accelerator area AAPO when the accelerator pedal 41 is fully depressed is equal to the throttle valve area ATVO when the throttle valve 23 is fully opened. The accelerator area AAPO when the accelerator pedal 41 is depressed halfway is equal to the throttle valve area ATVO when the throttle valve 23 is half open.

  However, at the time of acceleration (of course also during deceleration), as shown in FIG. 2A, the throttle valve opening TVO is increased by the response delay of the intake throttle valve device 22 with respect to the rise of the accelerator opening APO. Rise is delayed. Similarly, as shown in FIG. 9A, the rise of the intake throttle valve area ATVO is delayed by the response delay of the intake throttle valve device 22 with respect to the rise of the accelerator area AAPO.

  Here, the response delay of the throttle valve area ATVO with respect to the accelerator area AAPO (that is, the response delay of the intake throttle valve device 22) is regarded as the dead time T2 of the intake throttle valve device 22. However, the present invention is not limited to this, and the response delay of the intake throttle valve device 22 may be regarded as a first-order (or several-order) delay added to the dead time T2 of the intake throttle valve device 22. When the response delay of the intake throttle valve device 22 is regarded as the dead time T2 of the intake throttle valve device 22, the response waveform of the throttle valve area ATVO is a waveform obtained by translating the response waveform of the accelerator area AAPO to the right (see FIG. However, when the response delay of the intake throttle valve device 22 is regarded as a first-order delay added to the dead time T2 of the intake throttle valve device 22, the response waveforms of the throttle valve opening TVO and the throttle valve area ATVO are As shown in FIG. 2 (A) and FIG. 9 (A).

  The pressure ratio calculation unit 55 calculates the ratio Pma / Pa between the accelerator opening equivalent manifold part pressure Pma [Pa], which is the preceding pressure of the manifold part pressure, and the atmospheric pressure Pa [Pa] detected by the atmospheric pressure sensor 43 as shown in FIG. The corrected pressure ratio PRA [nameless number] is obtained by searching the table shown in FIG. The pressure ratio calculation unit 56 searches for the correction pressure by searching the table shown in FIG. 13 from the manifold part pressure Pm [Pa] itself and the ratio Pm / Pa of the atmospheric pressure Pa [Pa] detected by the atmospheric pressure sensor 43. The ratio PR [nameless number] is obtained. The pressure ratio ratio calculation unit 57 calculates a pressure ratio ratio PRR that is a ratio of the corrected pressure ratios PRA and PR by the following equation.

      PRR = PRA / PR (1).

  The accelerator opening equivalent flow rate calculation unit 58 corrects the air flow meter flow rate Qa with the above-described area ratio AAPO / ATVO and pressure ratio ratio PRR, that is, the accelerator opening equivalent flow rate Qaa as the intake throttle valve advance flow rate according to the following equation. [G / ms] is calculated.

    Qaa = Qa × (AAPO / ATVO) × PRR (2).

  Here, let us consider what happens to this accelerator opening equivalent flow rate Qaa during acceleration with reference to FIG. In FIG. 9, the accelerator area before acceleration is a first area AAPO1, and the accelerator area after acceleration is a second area AAPO2. The manifold part pressure before acceleration is defined as a first pressure Pm1, and the manifold part pressure after acceleration is defined as a second pressure Pm2.

  For simplicity, the correction pressure ratio PRA≈Pma / Pm and the correction pressure ratio PR≈Pm / Pa. At this time, PRR = PRA / PR = Pma / Pm. Therefore, the following equation is considered instead of the above equation (2).

    Qaa = Qa × (AAPO / ATVO) × (Pma / Pm) (Supplement 2).

  First, the area ratio (AAPO / ATVO) on the right side of (Supplement 2) gradually increases from 1.0 until the accelerator area reaches the second area AAPO2 from the first area AAPO1, and the accelerator area becomes the second area AAPO2. From when the intake throttle valve area ATVO rises, it remains constant, and after the intake throttle valve area ATVO rises, it gradually decreases until it reaches the second area AAPO2, and the intake throttle valve area ATVO becomes the second area. It becomes 1.0 when it matches AAPO2. On the other hand, the pressure ratio (Pma / Pm) gradually increases from 1.0 until the accelerator opening equivalent manifold part pressure Pma reaches the second pressure Pm2 from the first pressure Pm1, and the accelerator opening equivalent manifold part pressure Pma. Is maintained until the manifold pressure Pm rises from when the pressure reaches the second pressure Pm2, and gradually decreases until the manifold pressure Pm rises to coincide with the second pressure Pm2, so that the manifold pressure Pm It becomes 1.0 when it corresponds to 2 pressure Pm2. Since the flow rate Qaa is proportional to the area ratio and pressure ratio ratio thus changing, the flow rate Qaa suddenly rises and peaks at time t1, as shown in FIG. 9B, and then gradually. Becomes a waveform that matches the air flow meter flow rate Qa.

  Thus, the accelerator opening equivalent flow Qaa is a value obtained by advancing the air flow meter flow Qa until the phase when the air flow meter flow Qa responds matches the phase when the accelerator opening APO responds, that is, the air flow. The meter flow rate Qa is a value advanced by the dead time T2 of the intake throttle valve device 22.

  Actually, as shown in FIGS. 12 and 13, the correction pressure ratios PRA and PR are used instead of the pressure ratios Pma / Pm and Pm / Pm, and the correction pressure ratios PRA and PR are the pressure ratio Pma / Pa. , Pm / Pa is a value smaller than 1.0 in the vicinity of 1.0. The reason why the correction pressure ratios PRA and PR are made smaller than 1.0 when the pressure ratios Pma / Pa and Pm / Pa are close to 1.0 is as follows. That is, the pressure ratios Pma / Pa and Pm / Pa near 1.0 are high load areas, and in the high load areas, the actual flow rate is lower than the flow rate Qaa calculated by the above (Supplement 2). The correction pressure ratios PRA and PR are introduced, and the flow rate Qaa is adapted to the actual flow rate in the high load range.

  The characteristics of the corrected pressure ratio PRA in FIG. 12 are the same as the characteristics of the corrected pressure ratio PR in FIG. 13, and these characteristics are determined by the flow rate characteristics of the intake throttle valve device 22.

  In the manifold filling model 59 that inputs the accelerator opening equivalent flow rate Qaa calculated in this way, the manifold portion air amount Cma is calculated, and the accelerator opening equivalent cylinder air amount calculation unit 60 per one cycle performs this manifold portion air amount. An accelerator opening equivalent cylinder air amount Qca [g / cycle] per cycle is calculated using the amount Cm.

  Here, the combination of the manifold filling model and the cylinder air amount calculation unit per cycle is known by the technique disclosed in Japanese Patent Laid-Open No. 2001-50091, and in the present invention, it is used as shown in FIG. In the present invention, this known technique is applied, and the manifold filling model 59 and the accelerator opening equivalent cylinder air amount calculation unit 60 are configured as shown in FIG. As can be seen by comparing FIG. 7 with FIG. 8, which is a known technology itself, the present invention inputs the accelerator opening equivalent flow rate Qaa from the manifold portion inflow air amount calculation unit instead of the air flow meter flow rate Qa. . Due to this difference, in the present invention, the cylinder air amount Qc per cycle is advanced until the phase when the cylinder air amount Qc responds per cycle matches the phase when the accelerator opening APO responds, that is, As shown in FIG. 2, a value obtained by advancing the cylinder air amount Qc per cycle by the dead time T2 of the intake throttle valve device 22 is newly obtained. Therefore, this newly determined value is defined as the cylinder opening amount Qca corresponding to the accelerator opening per cycle (see).

  FIG. 9 also shows the cylinder opening amount Qca corresponding to the accelerator opening per cycle. At this time, only the difference in the response phase is considered, and therefore the unit difference from the injection amount (Tp, Tpf) is ignored. Has been.

  A detailed block diagram of FIG. 7 common to the two embodiments will be described. In FIG. 7, the manifold filling model 59 includes a manifold part inflow air amount calculation unit 81 and a manifold part air amount balance calculation unit 82. Further, the accelerator opening equivalent cylinder air amount calculation unit 60 includes an accelerator opening equivalent cylinder air amount calculation unit 85, a weighted average processing unit 86, and a unit conversion unit 87, and per cycle per predetermined time Δt. The accelerator opening equivalent cylinder air amount Qca [g / cycle] is repeatedly calculated. The predetermined time Δt is a control cycle, for example, 1 ms.

Here, as a premise, the pressure of the manifold part (collective name of collector 2, manifold 3 and port 4 in FIG. 1) is Pm [Pa], the volume of the manifold part is Vm [m ³ ], the air amount of the manifold part is Cm [g], The manifold part temperature is Tm [K]. Further, the pressure of the cylinder part (the combustion chamber 5 in FIG. 1) is Pc [Pa], the cylinder volume is Vc [m ³ ], and the cylinder part temperature is Tc [K]. Further, it is assumed that Pm = Pc and Tm = Tc (pressure and temperature do not change) between the manifold part and the cylinder part.

  The manifold portion inflow air amount calculation unit 81 multiplies the accelerator opening equivalent flow rate Qaa [g / ms] by the control cycle Δt (= 1 ms), that is, the amount of air flowing into the manifold portion per control cycle Δt by the following equation. Caa [g] is calculated.

    Caa = Qaa × Δt (3).

  The manifold part air amount balance calculating part 82 adds the air amount Caa [g] flowing into the manifold part to the previous value Cm (n-1) of the manifold part air quantity, and flows out from the manifold part to the cylinder part. A cylinder air amount Cca (n) [g] corresponding to the accelerator opening is subtracted, that is, a manifold air amount Cma (n) [g] is calculated by the following equation.

Cma (n) = Cma (n-1) + Caa-Cca (n) (4)
(4) The accelerator opening equivalent cylinder air amount Cca (n) on the right side of the equation (4) is the accelerator opening equivalent cylinder air amount calculated by the accelerator opening equivalent cylinder air amount calculation unit 85 in the previous time (a control period Δt before this time). This is the air amount Cca.

The accelerator opening equivalent cylinder air amount calculation unit 85 uses the following equation using the manifold portion air amount Cma (n), the cylinder volume Vc [m ³ ], and the manifold portion volume Vm [m ³ ] (Vc and Vm are constant values). To calculate the cylinder opening amount Cca (n) [g] corresponding to the accelerator opening.

    Cca (n) = Vc × Cma (n) / Vm (5).

  Equation (5) is obtained as follows. Since C = P · V / (R · T) from the gas state equation P · V = C · R · T, the following equation holds for the cylinder portion.

    Cc = Pc · Vc / (R · Tc) (Supplement 3).

  Here, since it is assumed that the cylinder part pressure Pc and the manifold part pressure Pm are equal and the cylinder part temperature Tc and the manifold part temperature Tm are equal, the following equation is obtained.

    Cc = Pm · Vc / (R · Tm) (Supplement 4).

  On the other hand, from the gas state equation P · V = C · R · T, since P / (R · T) = C / V, the following equation holds for the manifold portion.

    Pm / (R · Tm) = Cm / Vm (Supplement 5).

  Substituting this (complement 5) equation into (complement 4), the following holds.

    Cc = Vc · [Pm / (R · Tm)] = Vc · [Cm / Vm].

  Here, instead of the cylinder air amount Cc, the accelerator opening equivalent cylinder air amount Cca is obtained. Therefore, if Cca is used instead of Cc, the above equation (5) is obtained.

  The accelerator opening equivalent cylinder air amount Cca (n) calculated this time by the accelerator opening equivalent cylinder air amount calculation unit 85 is used in the manifold portion air amount balance calculation unit 82 next time. Thus, the manifold part air amount balance calculation unit 82 and the accelerator opening equivalent cylinder air amount calculation unit 85 perform cyclic calculation using the values of the other party.

  The weighted average processing unit 86 performs weighted average processing on the accelerator opening equivalent cylinder air amount Cca (= Cca (n)), that is, calculates the weighted average value Ccak [g] of the accelerator opening equivalent cylinder air amount by the following equation. calculate.

Ccak (n) = Ccak (n-1) * (1-M) + Cca * M (6)
Where Ccak (n) is the weighted average value of the cylinder air amount corresponding to the accelerator opening this time,
Ccak (n-1); Weighted average value of cylinder air volume corresponding to accelerator opening before Δt
M: Weighted average coefficient (0 <M <1).

  In the unit conversion unit 87, in order to make the weighted average value Ccak (= Ccak (n)) of the cylinder air amount corresponding to the accelerator opening correspond to the cycle period, one cycle is calculated by the following equation using the engine speed Ne [rpm]. It is converted into an accelerator opening equivalent cylinder air amount Qca [g / cycle] per crank angle (720 ° for a 4-cylinder engine).

    Qca = Ccak / (120 / Ne) (7).

On the other hand, the manifold part pressure calculation unit 83 uses the manifold part air amount Cma (= Cma (n)), the manifold part temperature Tm [K] detected by the temperature sensor 44, and the manifold part volume Vm [m ³ ]. The manifold part pressure Pm [Pa] is calculated from the equation.

Pm = Cma × R × (Tm / Vm) (8)
Expression (8) is a modification of the above (Supplement 5).

  The accelerator opening equivalent manifold part pressure calculation unit 84 calculates a pressure obtained by advancing the manifold part pressure Pm by the dead time T2 of the intake throttle valve device 22 as an accelerator opening equivalent manifold part pressure Pma [Pa].

  When the calculation of the accelerator opening equivalent cylinder air amount Qca [g / cycle], the manifold part pressure Pm, and the accelerator opening equivalent manifold part pressure Pma is completed in this way, the flow returns to FIG. 61 and the cylinder air amount equivalent injection amount calculation unit 62 divides the accelerator opening equivalent cylinder air amount Qca per cycle by the stoichiometric air fuel ratio (14.7), that is, the accelerator opening that provides the stoichiometric air fuel ratio by the following equation: The degree equivalent injection amount Tca [ms] is obtained.

Tca = (Qca / 14.7) × K1 (9)
However, K1; a coefficient (a constant value) for converting the air amount into the synchronous injection pulse width.

  Then, the required injection amount calculation unit 61 calculates a value obtained by delaying the accelerator opening equivalent injection amount Tca by the dead time T1 (a value obtained by adding a delay of T1 to Tca) as the required injection amount Tpf [ms]. Similarly, in the cylinder air amount equivalent injection amount calculation unit 62, a value obtained by delaying the accelerator opening equivalent injection amount Tca by the dead time T2 of the intake throttle valve device 22 (a value obtained by adding a delay of T2 to Tca) is used as the cylinder air. It is calculated as an amount equivalent injection amount Tp [ms] (an injection amount equivalent to the current cylinder air amount). Although expressed as an injection amount, the substance is the synchronous injection pulse width.

  Further, in the cylinder air amount calculation unit 65, a value obtained by delaying the cylinder air amount Qca corresponding to the accelerator opening per cycle by the dead time T2 [ms] of the intake throttle valve device 22 (a value obtained by adding a delay of T2 to Qca). Is calculated as a cylinder air amount Qc [g / cycle].

  The dead time T1 [ms] is calculated by the following equation from the dead time calculation unit 63 from the engine speed Ne [rpm] and the time of the intake throttle device 22 (for example, the dead time T2).

T1 = T2− (60 × 1000 / Ne) × (X1 / 360) (10)
However, X1; pre-crank angle section [deg].

  Here, the preemptive crank angle section X1 is the crank angle section from the synchronous injection timing IT to the intake valve closing timing IVC in FIGS. 2 and 9, and the second term on the right side of the equation (10) is the engine rotational speed Ne at that time. This is the time required to pass the pre-crank angle section X1 (that is, the injection amount setting time). At that time, 60 is multiplied to convert 1 minute into 1 second, and 1000 is further converted to convert second [s] into milliseconds [ms]. Therefore, the dead time T1 [ms] can be obtained by subtracting the injection amount setting time, which is the time corresponding to the pre-crank crank angle section K1, from the dead time T2 [ms] of the intake throttle valve device 22.

  The pre-crank crank angle section X1 is a constant value when the synchronous injection timing IT is determined in advance and the variable valve apparatus is not provided.

  The fuel injection amount calculation unit 64 calculates the fuel injection amount Ti [ms] for the sequential injection and the synchronous injection by using the required injection amount Tpf, that is, the following equation.

Ti = (Tpf + Kathos) × Tfbya × (α + αm−1) × 2 + Ts (11)
However, Kathos; transient correction amount [ms],
Tfbya; target equivalent ratio [anonymous number],
α: Air-fuel ratio feedback correction coefficient [anonymous number],
αm: air-fuel ratio learning value [anonymous number],
Ts: Invalid pulse width [ms],
Tpf; required injection amount [ms] in the present invention,
In the conventional apparatus, the pre-empty injection amount [ms] is 10 ms.

  The transient correction amount in the equation (11) is a value necessary for correcting the wall flow fuel. The target equivalent ratio Tfbya is 1.0 when the stoichiometric air-fuel ratio is used as the target air-fuel ratio, and is smaller than 1.0 when the air-fuel ratio leaner than the stoichiometric air-fuel ratio is used as the target air-fuel ratio. When the target air-fuel ratio is set as the target air-fuel ratio, the value is larger than 1.0.

  In the injection control (not shown), when the predetermined synchronous injection timing IT set before the intake valve opening timing IVO is reached, the fuel injection valve 21 is opened by this Ti for each cylinder.

  Also in the present invention, the cylinder cylinder air amount equivalent injection amount calculation unit 62 is provided to calculate the cylinder air amount equivalent injection amount Tp for connection with the conventional apparatus. That is, in the present invention, since the fuel injection amount Ti is calculated based on the required injection amount Tpf, the cylinder air amount equivalent injection amount Tp is not necessary for fuel injection control, but the conventional device does not require the cylinder air amount equivalent injection amount Tp. Since it may be used as an engine load and needs to be used in this case, in the present invention, the cylinder air amount equivalent injection amount Tp is obtained based on the accelerator opening equivalent cylinder air amount Qca per cycle. Then, similarly to the conventional device, engine control is performed using this cylinder air amount equivalent injection amount Tp as the engine load equivalent amount. Further, engine control is performed using the cylinder air amount Qc.

  Next, moving to the second embodiment, the second embodiment differs from the first embodiment in the method of calculating the cylinder air amount equivalent injection amount, and as shown in FIG. 6, the cylinder air amount equivalent injection amount Tp [ ms] is determined not from the accelerator opening equivalent cylinder air amount Qca per cycle but from the air flow meter flow rate Qa as in the conventional device. That is, based on the air flow meter flow rate Qa, the manifold filling model 71 and the cylinder air amount calculation unit 72 per cycle calculate the cylinder air amount Qck [g / cycle] per cycle, and the cylinder air amount Qck per cycle is calculated. Based on this, the cylinder air amount equivalent injection amount calculation unit 73 calculates the cylinder air amount equivalent injection amount Tp [ms] by the following equation.

Tp = (Qck / 14.7) × K1 (12)
However, K1; coefficient (constant value) for converting air quantity into synchronous injection pulse width,
The expression (12) is the same as the above (complement 1) expression.

  The cylinder air amount calculation unit 74 calculates the cylinder air amount Qck per cycle as it is as the cylinder air amount Qc [g / cycle].

  FIG. 8 is a detailed block diagram of the manifold filling model 71 and the cylinder air amount calculation unit 72 per cycle. In FIG. 8, a manifold filling model 71 includes a manifold portion inflow air amount calculation unit 91 and a manifold portion air amount balance calculation unit 92, and a cylinder air amount calculation unit 72 per cycle includes a cylinder air amount calculation unit 95 and a weighted average processing unit. 96 and a unit conversion unit 97 are provided, and the cylinder air amount Qck [g / cycle] per cycle is repeatedly calculated every predetermined time Δt. The predetermined time Δt is a control cycle, for example, 1 ms. However, since the configuration of FIG. 8 is the technology itself of Japanese Patent Laid-Open No. 2001-50091, detailed description thereof is omitted.

  Although both the first and second embodiments are shown in the control block diagram, this may be configured as a flowchart. At this time, the required injection amount Tpf, the fuel injection amount Ti, and the cylinder air amount equivalent injection amount Tp may be repeatedly calculated every short cycle (for example, every 10 ms) according to the flowchart. 5 to 8, the control cycle Δt is 1 ms, but is not limited to this.

  Here, the operation of the first and second embodiments will be described.

  Accelerator opening is a value obtained by advancing the air flow meter flow rate Qa, which has the same response phase as the accelerator opening APO, until the phase when the air flow meter flow rate Qa responds matches the phase when the accelerator opening APO responds. The degree-corresponding flow rate Qaa rises in the same phase as the accelerator opening APO rises during transition, for example, during acceleration (see FIG. 9C). On the other hand, since the intake throttle valve opening TVO rises with a predetermined response delay (T2) after the accelerator opening APO rises, if the accelerator opening equivalent flow Qaa is used, the response of the intake throttle valve opening TVO A response of the injection amount preceding the phase can be realized.

  In this case, as shown in FIG. 2, when the synchronous injection timing IT arrives at t2 delayed from the timing (t1) when the accelerator opening APO changes, the required injection amount Tpf at the synchronous injection timing IT (= t2). This required injection amount Tpf is subjected to a delay process for synchronizing with the required injection amount Tpf based on the accelerator opening equivalent flow rate Qaa or the accelerator opening equivalent flow rate Qaa. Based on the value, it can be calculated.

  The cylinder air amount equivalent injection amount Tp can be calculated based on a value delayed from the accelerator opening equivalent flow rate Qaa by the response delay (T2) of the intake throttle valve device 22. In other words, the cylinder air amount equivalent injection amount (Tp) can be calculated based on the value obtained by adding the response delay (T2) of the intake throttle valve device 22 to the accelerator opening equivalent flow rate Qaa.

  Further, the cylinder air amount Qc can also be calculated based on a value delayed by the response delay (T2) of the intake throttle valve device 22 with respect to the accelerator opening equivalent flow rate Qaa.

  As described above, according to the first and second embodiments, it is assumed that the engine is provided with the intake throttle valve device 22 that has a response delay until the intake throttle valve opening actually matches the intake throttle valve opening target value. The air flow meter 32 detects an air flow rate Qa upstream of the intake throttle valve, calculates the detected air flow rate Qa as an accelerator opening equivalent flow rate Qaa, and based on the accelerator opening equivalent flow rate Qaa or opens the accelerator. The required injection amount Tpf is calculated based on a value obtained by giving a predetermined delay to the degree-equivalent flow rate Qaa. Specifically, the air flow meter flow rate Qa is advanced by the accelerator opening equivalent flow rate calculation unit 58 until the phase when the detected air flow meter flow rate Qa responds matches the phase when the accelerator opening APO responds. This value is calculated as the accelerator opening equivalent flow rate Qaa, and the manifold filling model 59, the accelerator opening equivalent cylinder air amount calculation unit 60 per cycle, and the required injection amount calculation unit 61 reduce the intake throttle amount to this accelerator opening equivalent flow rate Qaa. Since the required injection amount Tpf is calculated on the basis of a value having a predetermined response delay (T1) shorter than the response delay (T2) of the valve device 22, the required injection amount Tpf is set to the transient (acceleration or deceleration). Therefore, the air-fuel ratio control accuracy at the time of transition is improved, so that response at the time of transient, exhaust performance and Costs can be improved. In particular, if the air-fuel ratio control accuracy during acceleration is improved, interrupt injection can be abolished, and transient adaptation is simplified. In addition, the improvement of the air-fuel ratio control accuracy at the time of transition makes it easy to adapt the wall flow correction.

  Further, according to the first and second embodiments, the airflow is premised on an engine including an intake throttle valve device that has a response delay until the intake throttle valve opening actually matches the intake throttle valve opening target value. The air flow Qa upstream of the intake throttle valve is detected by the meter 32, and the air flow compensated for the response delay of the intake throttle valve opening TVO with respect to the accelerator opening APO is detected from the detected air flow Qa. Qaa is calculated, and a cylinder air amount equivalent injection amount Tp is calculated based on this accelerator opening equivalent flow rate Qaa or a value obtained by giving a predetermined delay (T1) to the accelerator opening equivalent flow rate Qaa. Since the engine control is performed using the air amount equivalent injection amount Tp as the engine load equivalent amount, the configuration is different from that of the conventional device and the same cylinder air amount as that of the conventional device. It is possible to obtain the injection amount Tp.

  Further, according to the first and second embodiments, the airflow is premised on an engine including an intake throttle valve device that has a response delay until the intake throttle valve opening actually matches the intake throttle valve opening target value. The air flow Qa upstream of the intake throttle valve is detected by the meter 32, and the air flow compensated for the response delay of the intake throttle valve opening TVO with respect to the accelerator opening APO is detected from the detected air flow Qa. Qaa is calculated, and the cylinder air amount Qc is calculated based on the accelerator opening equivalent flow rate Qaa or based on a value obtained by giving a predetermined delay (T1) to the accelerator opening equivalent flow rate Qaa. Therefore, the same cylinder air amount Qc as that of the conventional apparatus can be obtained with a configuration different from that of the conventional apparatus.

  Further, according to the first and second embodiments, the response delay of the intake throttle valve device 22 is the dead time T2 of the intake throttle valve device, so that the configuration can be simplified.

  Further, since the cylinder air amount Qc is determined at the intake valve closing timing IVC, in order to obtain the theoretical air fuel ratio (target air fuel ratio) at this time, the injection amount corresponding to the determined cylinder air amount is set at the synchronous injection timing IT. However, according to the first and second embodiments, as shown in the above equation (10), the crank angle interval from the synchronous injection timing IT to the intake valve closing timing IVC (the preemptive crank angle interval X ) Is set as the injection amount setting time, so that the required injection amount Tpf, which is sufficient to obtain the target air-fuel ratio when the cylinder air amount is determined at the injection valve closing timing IVC, is responded with the synchronous injection timing IT. It becomes possible to give without delay, and this improves the air-fuel ratio control accuracy at the time of transition.

  Further, according to the first and second embodiments, as shown in the above equation (10), the time required for the crank angle section (the preemptive crank angle section X) from the synchronous injection timing IT to the intake valve closing timing IVC is reduced. Since the calculation is based on the engine rotation speed Ne, even if the engine rotation speed Ne is different, the required injection without excess or deficiency for obtaining the target air-fuel ratio when the cylinder air amount is fixed at the injection valve closing timing IVC. The amount Tpf can be given without a delay in response at the synchronous injection timing IT, which improves the air-fuel ratio control accuracy at the time of transition regardless of the engine speed Ne.

  FIG. 14 is a third embodiment for the case where a VTC mechanism 27 is provided in addition to the intake throttle valve device 22, and replaces FIG. 7 of the first embodiment. In FIG. 14, the same parts as those in FIG. 7 of the first embodiment are given the same numbers.

  Prior to the description of the block diagram of FIG. 14 (partially detailed block diagram of FIG. 5), the concept of fuel injection control of an engine equipped with a variable valve gear will be described with reference to FIG.

  FIG. 16 is a waveform diagram showing a response when the target value of the variable valve apparatus is changed.

  Here, the target value of the variable valve device is at least one target value of the intake valve opening timing, intake valve closing timing, exhaust valve opening timing, exhaust valve closing timing, intake valve valve lift or intake valve operating angle. It is.

  Here, for the sake of simplicity, there is no intake throttle valve device, and at least one of intake valve opening timing, intake valve closing timing, exhaust valve opening timing, exhaust valve closing timing, intake valve valve lift or intake valve operating angle Of the so-called non-throttle engine that includes a variable valve device that can arbitrarily control the intake valve, a non-throttle engine that includes only the VTC mechanism 27 that can arbitrarily control the opening / closing timing of the intake valve is considered. In this non-throttle engine, the target values of the variable valve gear are the intake valve opening timing target value and the intake valve closing timing target value. In this case, because of the mechanism of the VTC mechanism 27, the crank angle (opening crank angle) from the intake valve opening timing IVO to the intake valve closing timing IVC is constant and does not change. It shows.

  As to how the intake valve opening timing target value and the intake valve closing timing target value are determined in accordance with the operating conditions determined from the engine speed and the engine load, Japanese Patent Application Laid-Open Nos. 2003-129871, 2003-65131, Since it is described in Japanese Patent Application Laid-Open No. 11-2140, the description thereof is omitted. For example, when accelerating from a low load state to a high load state, the intake and exhaust valves 15 and 16 overlap as shown in FIG. , That is, the opening / closing timing target value of the intake valve 15 changes toward the advance side.

  FIG. 16 shows that the intake valve 15 is opened at the timing t11 because the opening timing target value IVOm and the closing timing target value IVCm are accelerated from the first opening timing IVOm1 and the first closing timing IVCm1 of the intake valve 15. FIG. 10 is a response waveform diagram when the valve 15 is advanced to a second opening timing IVOm2 and a second closing timing IVCm2 and thereafter the second opening timing IVOm2 and the second closing timing IVCm2 are maintained. At this time, since the variable valve device also has a predetermined response delay (Tv2) similar to the intake throttle valve device 22 described in the first and second embodiments, it is the actual opening / closing timing of the intake valve 15. The actual opening timing value IVOr and the closing timing actual value IVCr of the intake valve 15 finally advance at the timing t14. Even if the opening timing actual value IVOr and the closing timing actual value IVCr of the intake valve 15 are advanced, there is a delay in the air response, so that the cylinder air amount Qc rises at a timing t15 that is further delayed than the timing t14. In FIG. 16, as in FIG. 2, for the sake of convenience, the injection amount and the air amount are aligned at the same height.

  The basic concept of fuel injection control when the variable valve device is provided is the same as the basic concept of fuel injection control when the intake throttle valve device is provided. That is, in the case of the variable valve operating apparatus, the opening timing actual value IVOr and the closing timing actual value IVCr of the intake valve 15 with respect to the opening timing target value IVOm and the closing timing target value IVCm of the intake valve 15 are responses from t11 to t14. There is a delay, in fact, a dead time Tv2 of about 40-50 ms. This means that if the opening timing target value IVOm and the closing timing target value IVCm of the intake valve 15 are used for the calculation of the fuel injection amount, the response phase of the opening timing actual value IVOr and the closing timing actual value IVCr of the intake valve 15 A response of the preceding required injection amount can be realized. For that purpose, the actual opening timing value IVOr and the closing timing actual value IVCr of the intake valve 15 are set, and the phase when the opening timing actual value IVOr and the closing timing actual value IVCr of the intake valve 15 respond is set as the opening timing target of the intake valve 15. The values advanced until the value IVOm and the closing timing target value IVCm coincide with the response phase are calculated as the opening timing preemption value IVOff and the closing timing preemption value IVCff of the intake valve 15 (see FIG. 16B). Delay processing for synchronizing the required injection amount Tpf with the opening timing advance value IVOff and the closing timing advance value IVCff of the intake valve 15, in FIG. 16, delay processing of the dead time Tv <b> 1 is performed, and FIG. An opening timing request value IVOf and a closing timing request value IVCf of the intake valve 15 are calculated.

  Looking at this as changes in the cylinder air amount and the injection amount, as shown in FIG. 16D, a preemptive value that is the cylinder air amount corresponding to the opening timing preemptive value IVOff and the closing timing preemptive value IVCff of the intake valve 15. The equivalent cylinder air amount Qcff rises earlier than the cylinder air amount Qc by the response delay (Tv2) of the variable valve device, and the intake valve 15 opens after the dead time Tv1 after the preemptive value equivalent cylinder air amount Qcff. The required injection amount Tpf corresponding to the timing required value IVOf and the closing timing required value IVCf rises.

  Here, the response delay of the intake valve 15 opening timing actual value IVOr and the closing timing actual value IVCr with respect to the opening timing target value IVOm of the intake valve 15 and the closing timing target value IVCm (that is, the response delay of the variable valve operating device) is variable. The dead time Tv2 of the valve device is considered. However, the present invention is not limited to this, and the response delay of the variable valve device may be regarded as a first-order (or several-order) delay added to the dead time Tv2 of the variable valve device. When the response delay of the variable valve device is regarded as the dead time Tv2 of the variable valve device, the response waveforms of the actual opening timing value IVOr and the closing timing actual value IVCr of the intake valve 15 are the opening timing target value IVOm of the intake valve 15. The response waveform of the closing timing target value IVCm is a waveform (not shown) that is simply translated to the right, but the response delay of the variable valve device is added to the dead time Tv2 of the variable valve device. When considered, the response waveforms of the actual opening timing value IVOr and the closing timing actual value IVCr of the intake valve 15 are as shown in FIGS. 16 (A) and 16 (B).

  Since the horizontal axis in FIG. 16 is a time axis, the synchronous injection timing IT changes when the engine rotational speed Ne becomes higher or lower than the predetermined value N0. When the engine rotational speed Ne becomes lower than the predetermined value N0, the synchronous injection timing IT is delayed from the position shown in the figure (moves to the right in the figure), and conversely, when the engine rotational speed Ne becomes higher than the predetermined value N0, synchronous injection is performed. The timing IT is earlier than the illustrated position (moves to the left in the figure). That is, since the dead time Tv1 varies depending on the engine speed Ne, the dead time Tv1 needs to be determined according to the engine speed Ne.

  This concludes the description of the basic concept of fuel injection control when a variable valve operating device is provided.

  The difference from the first embodiment will be mainly described. In FIG. 14, unlike the first embodiment shown in FIG. 7, a cylinder volume calculation unit 101 is newly provided. The cylinder volume calculation unit 101 includes an intake valve. The cylinder volume Vc is calculated based on the actual closing timing value IVCr, and the accelerator opening equivalent cylinder air amount calculation unit 85 uses the calculated cylinder volume Vc to calculate the accelerator opening equivalent cylinder air amount according to the above equation (5). Cca (n) [g] is calculated.

  Here, the cylinder volume Vc is calculated based on the intake valve closing timing actual value IVCr for the following reason. That is, when the variable valve mechanism is provided, the cylinder volume Vc of the fresh air substantially changes due to the difference in the intake valve closing timing actual value IVCr, and the cylinder air amount Vc changes accordingly. This means that the accelerator opening equivalent cylinder air amount Qca (n) [g] also changes due to the difference in the cylinder volume Vc. Therefore, the cylinder volume Vc is calculated based on the intake valve closing timing actual value IVCr.

  The calculation of the cylinder volume Vc will be described in detail with reference to the block diagram of FIG. 15 (detailed block diagram of the cylinder volume calculation unit 101 in FIG. 14). FIG. 15 shows calculation of the cylinder volume Vc, which is executed every predetermined time Δt (for example, every 1 ms).

  Here, the technique described in Japanese Patent Laid-Open No. 2001-50091 is basically used for calculating the cylinder volume. And with respect to this basic technique, in the third embodiment, an intake valve opening / closing timing required value calculation unit 111 is newly added. The intake valve opening / closing timing required value calculation unit 111 includes an intake valve closing timing advance value calculation unit 112, an intake valve opening timing advance value calculation unit 113, a dead time calculation unit 114, an intake valve closing timing request value calculation unit 115, and an intake valve opening. A time requirement value calculation unit 116 is provided.

  First, the intake valve closing timing preemptive value calculation unit 112 calculates an intake valve closing timing advance value IVCff obtained by advancing the intake valve closing timing actual value IVCr by the dead time Tv2 of the variable valve operating apparatus. Similarly, the intake valve opening timing preemptive value calculating unit 113 calculates the intake valve opening timing obtained by advancing the intake valve opening timing actual value IVOr by the dead time Tv2 of the variable valve operating apparatus as the intake valve opening timing preempting value IVOff. To do.

  The intake valve closing timing actual value IVCr and the intake valve opening timing actual value IVOr are directly detected by providing the lift sensor 46 for the intake valve 15.

  The intake valve closing timing request value calculation unit 115 calculates a value obtained by delaying the intake valve closing timing advance value IVCff by the dead time Tv1 as the intake valve closing timing request value IVCf. Similarly, the intake valve opening timing required value calculation unit 116 calculates a value obtained by delaying the intake valve opening timing preemptive value IVOff by the dead time Tv1 as the intake valve opening timing required value IVOf.

  The dead time Tv1 [ms] is calculated by the dead time calculation unit 114 from the engine rotational speed Ne [rpm] and the dead time Tv2 of the variable valve operating apparatus according to the following equation.

Tv1 = Tv2− (60 × 1000 / Ne) × (X1 / 360) (13)
However, X1; pre-crank angle section [deg].

  Here, the preemptive crank angle section X1 is a crank angle section from the synchronous injection timing IT to the intake valve closing timing actual value IVCr in FIG. 16, and the second term on the right side of the equation (13) is the predecessor engine speed Ne at this time. The time required for passing the crank angle section X1 (that is, the injection amount setting time) is calculated. At that time, 60 is multiplied to convert 1 minute to 1 second, and 1000 is further multiplied to convert the unit of seconds [s] to the unit of millisecond [ms]. Accordingly, the dead time Tv1 [ms] can be obtained by subtracting the injection amount setting time, which is the time corresponding to the pre-crank crank angle section K1, from the dead time Tv2 [ms] of the variable valve operating apparatus.

  The pre-crank crank angle section X2 is calculated in crank angle units [deg] from the intake valve closing timing actual value IVCr detected by the lift sensor 46 and the synchronous injection timing IT.

The target cylinder volume calculation unit 117 calculates the cylinder volume at that time from the intake valve closing timing request value IVCf, and sets this as the target cylinder volume Vcm [m ³ ].

The cylinder fresh air ratio calculation unit 118 calculates the cylinder fresh air ratio η [%] based on the intake valve opening timing required value IVOf, the exhaust valve closing timing EVC (constant value), and, if necessary, the EGR rate. The volume calculation unit 119 calculates the actual cylinder volume Vcr [m ³ ] = Vcm · η by multiplying the target cylinder volume Vcm by the cylinder fresh air ratio η. This is to obtain the cylinder volume of only fresh air in the cylinder.

  The overlap amount is determined by the exhaust valve closing timing EVC and the intake valve opening timing actual value IVOr, and the amount of inert gas (internal EGR amount) remaining in the cylinder increases as the overlap amount increases. The fresh air ratio η is basically obtained based on the overlap amount. Further, in an engine equipped with a variable valve operating device, the internal EGR amount can be freely controlled by controlling the overlap amount. Therefore, in general, an EGR device (external EGR device) is not provided, but when an external EGR device is provided, Furthermore, it correct | amends with the EGR rate of an external EGR apparatus, and calculates | requires the final in-cylinder fresh air ratio (eta).

The actual cylinder volume change rate calculation unit 120 multiplies the actual cylinder volume Vcr [m ³ ] by the engine rotation speed Ne [rpm], that is, calculates the actual cylinder volume change rate ΔVc [m ³ / ms] by the following equation.

    ΔVc = Vcr × Ne × K2 (14).

Here, K2 in the equation (14) is a constant for aligning units, and K2 = (1/30) × (1/1000). 1/30 is for converting the unit of the engine rotational speed Ne from [rpm] to [180 deg / sec], and 1/1000 is the unit of the actual cylinder volume change rate ΔVc [m ³ / s. ] To [m ³ / ms].

The cylinder volume calculation unit 121 multiplies the actual cylinder volume change rate ΔVc by the control cycle Δt, that is, calculates the cylinder volume Vc [m ³ ] by the following equation.

    Vc = ΔVc × Δt (15).

  Here, the effect of 3rd Embodiment is demonstrated with reference to FIG.

  The actual opening timing value IVOr and the closing timing actual value IVCr of the intake valve 15 are set to the phase when the opening timing actual value IVOr and the closing timing actual value IVCr of the intake valve 15 respond, and the opening timing target value IVOm of the intake valve 15 is closed. The opening timing advance value IVOff and the closing timing advance value IVCff of the intake valve 15 which are values advanced until the timing target value IVCm coincides with the phase at the time of response are the transition time target value of the intake valve 15 at the time of transition, for example, during acceleration. The IVOm and the closing timing target value IVCm change to the advance side in the same phase as the change to the advance side (see FIG. 16B). On the other hand, the actual opening timing value IVOr and the actual closing timing value IVCr of the intake valve 15 are the response delay of the variable valve gear after the opening timing target value IVOm and the closing timing target value IVCm of the intake valve 15 are changed to the advance side. It changes with (Tv2).

  FIG. 16D shows how the cylinder air amount changes in response to the change in the intake valve closing timing. The intake valve 15 corresponding to the opening timing advance value IVOff and the closing timing advance value IVCff of the intake valve 15 is such that the opening timing target value IVOm and the closing timing target value IVCm of the intake valve 15 change to the advance side. On the other hand, the cylinder air amount Qc corresponding to the opening timing actual value IVOr and the closing timing actual value IVCr of the intake valve 15 rises after the preemptive value equivalent cylinder air amount Qcff rises. It rises with a response delay (Tv2). Accordingly, if the preemptive value equivalent cylinder air amount Qcff, that is, the opening timing preemptive value IVOff of the intake valve 15 and the closing timing preemptive value IVCff are used, the response phase of the actual opening timing value IVOr and the closing timing actual value IVCr of the intake valve 15 A preceding injection amount response can be realized.

  In this case, if the synchronous injection timing IT arrives at a timing when the opening timing target value IVOm and the closing timing target value IVCm of the intake valve 15 change or after that timing, the required injection amount Tpf needs to be given at this synchronous injection timing IT. This required injection amount Tpf is a value obtained by performing a delay process (Tv1) for synchronizing with the required injection amount Tpf with respect to the opening timing advance value IVOff and the closing timing advance value IVCff of the intake valve 15. 15 based on the required opening timing value IVOf and the closing timing required value IVCf).

  Further, the cylinder air amount equivalent injection amount Tp is calculated based on a value obtained by delaying the response timing (Tv2) of the variable valve device with respect to the opening timing advance value IVOff and the closing timing advance value IVCff of the intake valve 15. Can do. In other words, it can be calculated based on values obtained by adding a response delay (Tv2) of the variable valve gear to the opening timing advance value IVOff and the closing timing advance value IVCff of the intake valve 15.

  Further, the cylinder air amount Qc can also be calculated based on values obtained by adding a response delay (Tv2) of the variable valve gear to the opening timing advance value IVOff and the closing timing advance value IVCff of the intake valve 15.

  Thus, according to the third embodiment, the actual opening timing value IVOr and the closing timing actual value IVCr (actual amount of control amount) of the intake valve 15 are the opening timing target value IVOm and the closing timing target value IVCm of the intake valve 15. On the premise of an engine having a variable valve system that has a response delay (Tv2) until it matches the (control amount target value), the air flow meter 32 detects the air flow rate Qa in the intake passage and compensates for the response delay. Values are calculated as an opening timing preemption value IVOff and a closing timing preemption value IVCff of the intake valve 15, and based on the opening timing preemption value IVOff of the intake valve 15, the closing timing preemption value IVCff and the detected air flow rate Qa or The opening timing required value IVOff of the intake valve 15 which is a value obtained by giving a predetermined delay (Tv1) to the opening timing advance value IVOff and the closing timing advance value IVCff of the intake valve 15; Since the required injection amount Tpf is calculated based on the required timing value IVCf and the detected air flow rate Qa, and this required injection amount Tpf is used for fuel injection control, the required injection amount Tpf is used as the opening timing target of the intake valve 15. Since the value IVOm and the closing timing target value IVCm can be given without a response delay compared to the conventional case at the time of transition where the advance value or the retard value changes, the air-fuel ratio control accuracy at the time of transient is improved. Even in the engine equipped, the response at the time of transition, exhaust performance and fuel consumption can be improved. In particular, if the air-fuel ratio control accuracy during acceleration is improved, interrupt injection can be abolished, and the transient adaptation is simplified. In addition, the improvement of the air-fuel ratio control accuracy at the time of transition makes it easy to adapt the wall flow correction.

  Further, according to the third embodiment, the response delay (Tv2) until the actual opening timing value IVOr and the closing timing actual value IVCr of the intake valve 15 coincide with the opening timing target value IVOm and the closing timing target value IVCm of the intake valve 15. Assuming an engine equipped with a variable valve system having a), the air flow meter 32 detects the air flow rate Qa in the intake passage, and the values compensated for the response delay are the opening timing preemptive value IVOrr and the closing timing preempting value. Calculated as IVCff, based on the opening timing advance value IVOff, the closing timing advance value IVCff of the intake valve 15 and the detected air flow rate Qa, or the opening timing advance value IVOff of the intake valve 15 and the closing timing advance value IVCff Are detected as the opening timing required value IVOf and the closing timing required value IVCf of the intake valve 15, which are values having a predetermined delay (Tv1). Since the cylinder air amount equivalent injection amount Tp is calculated based on the air flow rate Qa and the engine control is performed using this cylinder air amount equivalent injection amount Tp as the engine load equivalent amount, even in an engine equipped with a variable valve gear, The same cylinder air amount equivalent injection amount (Tp) as that of the conventional apparatus can be obtained with a configuration different from that of the conventional apparatus.

  Further, according to the third embodiment, the response delay (Tv2) until the actual opening timing value IVOr and the closing timing actual value IVCr of the intake valve 15 coincide with the opening timing target value IVOm and the closing timing target value IVCm of the intake valve 15. Assuming that the engine is equipped with a variable valve system having an intake valve), the air flow meter 32 detects the air flow rate Qa of the intake passage, and the values compensated for the response delay are the opening timing preemptive value IVOff and the closing timing preemptive value. Calculated as IVCff, based on the opening timing advance value IVOff and closing timing advance value IVCff of the intake valve 15 and the detected air flow rate Qa, or predetermined to the opening timing advance value IVOff and closing timing advance value IVCff of the intake valve The required opening timing value IVOf, the closing timing required value IVCf of the intake valve 15 and the detected air flow rate, which are values having a delay (Tv1). Calculating the cylinder intake air amount Qc based on the a, since the engine control using the cylinder air quantity Qc, a different structure from the conventional apparatus, it is possible to obtain the same cylinder air quantity Qc and the conventional device.

  Further, according to the third embodiment, the response delay of the variable valve operating device is the dead time Tv2 of the variable valve operating device, so the configuration can be simplified.

  Further, since the cylinder air amount Qc is determined to the intake valve closing timing actual value IVCr, in order to obtain the theoretical air fuel ratio (target air fuel ratio) at this time, the injection amount corresponding to the determined cylinder air amount is set to the synchronous injection timing. According to the third embodiment, it is necessary to give it by IT, as shown in the above equation (13), the crank angle section (pre-crank crank angle section X2) from the synchronous injection timing IT to the intake valve closing timing actual value IVCr. ) Is set as the injection amount setting time, the required injection amount Tpf that is sufficient to obtain the target air-fuel ratio when the cylinder air amount is fixed at the injection valve closing timing actual value IVCr is set to the synchronous injection timing IT. Thus, it is possible to give the response without delay, which improves the accuracy of the air-fuel ratio control during the transition.

  Further, according to the third embodiment, as shown in the above equation (13), the time required for the crank angle section (preliminary crank angle section X2) from the synchronous injection timing IT to the intake valve closing timing actual value IVCr is determined by the engine. Since the calculation is based on the rotational speed Ne, even if the engine rotational speed Ne is different, there is no excess or shortage in order to obtain the target air-fuel ratio when the cylinder air amount is fixed at the actual valve closing timing IVCr. The injection amount Tpf can be given without a delay in response at the synchronous injection timing IT, thereby improving the air-fuel ratio control accuracy at the time of transition regardless of the engine speed Ne.

  The function of the intake throttle valve preemptive flow rate calculation means described in the claims is the accelerator opening equivalent flow rate calculation unit 58 of FIG. 5, and the function of the required injection amount calculation means is the manifold filling model 59 of FIG. The function corresponding to the cylinder air amount equivalent injection amount calculation unit is performed by the cylinder air amount equivalent injection amount calculation unit 62 of FIG. 5 by the opening degree equivalent cylinder air amount calculation unit 60 and the required injection amount calculation unit 61, respectively.

  Further, the function of the cylinder air amount calculating means is performed by the cylinder air amount calculating unit 65 of FIG.

  Further, the intake throttle valve advance area described in the claims corresponds to the accelerator area described in the embodiment, and the intake throttle valve advance flow rate described in the claims corresponds to the accelerator opening equivalent flow volume described in the embodiment. Correspond.

The schematic block diagram which shows one Embodiment of this invention. The wave form diagram for demonstrating the basic view of the fuel-injection control of this invention. The wave form diagram which shows the present fuel injection control and its limit. The wave form diagram which shows the present fuel injection control and its limit. The control block diagram of 1st, 3rd embodiment. The control block diagram of 2nd Embodiment. FIG. 5 is a detailed block diagram of a manifold filling model common to the first and second embodiments and an accelerator opening equivalent cylinder air amount calculation unit per cycle. The detailed block diagram of the manifold filling model of 2nd Embodiment and the cylinder air quantity calculation part per cycle. The wave form diagram for demonstrating the effect | action at the time of acceleration common to 1st, 2nd embodiment. Accelerator area characteristic diagram. The characteristic diagram of the throttle valve area. The characteristic figure of correction | amendment pressure ratio. The characteristic figure of correction | amendment pressure ratio. The detailed block diagram of the manifold filling model of 3rd Embodiment and the cylinder air quantity calculation part equivalent to the accelerator opening per cycle. The detailed block diagram of a cylinder volume calculation part. The wave form diagram for demonstrating the basic view of the fuel-injection control of 3rd Embodiment. The characteristic figure of the valve lift of an intake / exhaust valve.

Explanation of symbols

21 Fuel Injection Valve 22 Intake Throttle Valve Device 26 VEL Mechanism (Variable Valve Actuator)
27 VTC mechanism (Variable valve operating device)
31 Engine controller 32 Air flow meter (Air flow rate detection means)
41 accelerator pedal 42 accelerator sensor (accelerator opening detection means)

Claims (13)

An accelerator opening detecting means for detecting the amount of depression of the accelerator pedal as an accelerator opening;
It is not mechanically connected to the accelerator pedal, the target value of the intake throttle valve opening is determined according to the accelerator opening, and predetermined until the intake throttle valve opening actually matches the target value of the intake throttle valve An intake throttle device having a response delay of
Throttle valve opening detection means for detecting the actual intake throttle valve opening;
An air flow rate detecting means for detecting an air flow rate upstream of the intake throttle valve;
By multiplying the air flow rate by a ratio of the intake throttle valve advance area determined by the accelerator opening and the throttle valve area determined by the actual intake throttle valve opening , the phase at which the air flow rate responds is opened. An intake throttle valve pre-empty flow rate calculating means for calculating an intake throttle valve pre-empty flow rate that is a value advanced until the phase coincides with the phase when responding ;
An accelerator opening equivalent cylinder air amount calculating means for calculating an accelerator opening equivalent cylinder air amount per cycle based on the intake throttle valve pre-flow amount;
An accelerator opening equivalent injection amount calculating means for calculating an accelerator opening equivalent injection amount for obtaining a theoretical air-fuel ratio based on the cylinder opening equivalent cylinder air amount per cycle;
Requested injection for calculating as a required injection amount a value delayed by a predetermined dead time for obtaining a target air-fuel ratio with a cylinder air amount corresponding to the accelerator opening per cycle to determine this accelerator opening equivalent injection amount at the intake valve closing timing A quantity calculating means;
Fuel injection control means using this required injection amount for fuel injection control;
An engine control device comprising: The intake throttle valve pre-flow rate calculating means further includes a correction pressure ratio calculated based on a ratio of the accelerator opening equivalent manifold portion pressure and the atmospheric pressure, which is a preceding pressure of the manifold portion pressure, and the manifold portion pressure itself and the atmospheric pressure. An intake throttle valve pre-flow rate is calculated based on the pressure ratio ratio to the correction pressure ratio calculated based on the ratio of
The engine control device according to claim 1. The intake throttle valve preemptive flow rate calculation means calculates an intake throttle valve preemptive flow rate Qaa based on the following equation:
Qaa = Qa × (AAPO / ATVO) × (PRA / PR),
However,
Qa: the air flow rate upstream of the intake throttle valve,
AAPO; intake throttle valve advance area determined by accelerator opening,
ATVO: throttle valve area determined by the actual opening of the throttle valve,
PRA: corrected pressure ratio calculated based on the ratio of the accelerator opening equivalent manifold portion pressure and the atmospheric pressure, which is the preceding pressure of the manifold portion pressure,
PR: correction pressure ratio calculated based on the ratio of the manifold part pressure itself and the atmospheric pressure ,
The engine control device according to claim 2 . The intake throttle valve advance area is an area determined based on the accelerator opening detected by the accelerator opening detector .
The engine control device according to any one of claims 1 to 3, wherein the engine control device is characterized in that: The throttle valve area is an area that is determined based on the opening of the actual intake throttle valve .
The engine control device according to any one of claims 1 to 4, wherein the engine control device is characterized in that: The response delay of the intake throttle valve device is obtained by adding a first-order or several-order delay to the dead time of the intake throttle valve device .
The engine control apparatus according to any one of claims 1 to 5, wherein the engine control apparatus is configured as described above. The response delay of the intake throttle device is a dead time of the intake throttle device .
The engine control apparatus according to any one of claims 1 to 5 , wherein the engine control apparatus is configured as described above. Calculating the predetermined dead time based on a time of the intake throttle valve device and an injection amount set time ;
The engine control apparatus according to claim 6 or 7 , characterized in that The injection amount set time is the time required for the crank angle section from the synchronous injection timing to the intake valve closing timing .
The engine control device according to claim 8 . The time required for the crank angle section from the synchronous injection timing to the intake valve closing timing is calculated based on the engine speed .
The engine control apparatus according to claim 9. An accelerator opening detecting means for detecting the amount of depression of the accelerator pedal as an accelerator opening;
It is not mechanically connected to the accelerator pedal, the target value of the intake throttle valve opening is determined according to the accelerator opening, and predetermined until the intake throttle valve opening actually matches the target value of the intake throttle valve An intake throttle device having a response delay of
Throttle valve opening detection means for detecting the actual intake throttle valve opening;
An air flow rate detecting means for detecting an air flow rate upstream of the intake throttle valve;
By multiplying the air flow rate by a ratio of the intake throttle valve advance area determined by the accelerator opening and the throttle valve area determined by the actual intake throttle valve opening, the phase at which the air flow rate responds is opened. An intake throttle valve pre-empty flow rate calculating means for calculating an intake throttle valve pre-empty flow rate that is a value advanced until the phase coincides with the phase when responding;
An accelerator opening equivalent cylinder air amount calculating means for calculating an accelerator opening equivalent cylinder air amount per cycle based on the intake throttle valve pre-flow amount;
An accelerator opening equivalent injection amount calculating means for calculating an accelerator opening equivalent injection amount for obtaining a theoretical air-fuel ratio based on the cylinder opening equivalent cylinder air amount per cycle;
A cylinder air amount equivalent injection amount calculating means for calculating a value obtained by delaying the accelerator opening equivalent injection amount by the dead time of the intake throttle valve device as an injection amount equivalent to the current cylinder air amount;
Means for performing engine control using the cylinder air amount equivalent injection amount as the engine load equivalent amount;
An engine control device comprising: The intake throttle valve pre-flow rate calculating means further includes a correction pressure ratio calculated based on a ratio of the accelerator opening equivalent manifold portion pressure and the atmospheric pressure, which is a preceding pressure of the manifold portion pressure, and the manifold portion pressure itself and the atmospheric pressure. An intake throttle valve pre-flow rate is calculated based on the pressure ratio ratio to the correction pressure ratio calculated based on the ratio of
The engine control device according to claim 11 . An accelerator opening detecting means for detecting the amount of depression of the accelerator pedal as an accelerator opening;
It is not mechanically connected to the accelerator pedal, the target value of the intake throttle valve opening is determined according to the accelerator opening, and predetermined until the intake throttle valve opening actually matches the target value of the intake throttle valve An intake throttle device having a response delay of
Throttle valve opening detection means for detecting the actual intake throttle valve opening;
An air flow rate detecting means for detecting an air flow rate upstream of the intake throttle valve;
By multiplying the air flow rate by a ratio of the intake throttle valve advance area determined by the accelerator opening and the throttle valve area determined by the actual intake throttle valve opening, the phase at which the air flow rate responds is opened. An intake throttle valve pre-empty flow rate calculating means for calculating an intake throttle valve pre-empty flow rate that is a value advanced until the phase coincides with the phase when responding;
An accelerator opening equivalent cylinder air amount calculating means for calculating an accelerator opening equivalent cylinder air amount per cycle based on the intake throttle valve pre-flow amount;
A cylinder air amount calculating means for calculating a cylinder air amount as a value obtained by delaying the cylinder air amount corresponding to the accelerator opening per cycle by the dead time of the intake throttle valve device;
Means for performing engine control using the cylinder air amount;
An engine control device comprising:

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