WO2022224516A1 - 内燃機関の制御装置 - Google Patents
内燃機関の制御装置 Download PDFInfo
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- WO2022224516A1 WO2022224516A1 PCT/JP2022/002721 JP2022002721W WO2022224516A1 WO 2022224516 A1 WO2022224516 A1 WO 2022224516A1 JP 2022002721 W JP2022002721 W JP 2022002721W WO 2022224516 A1 WO2022224516 A1 WO 2022224516A1
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- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/0025—Controlling engines characterised by use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
- F02D41/0047—Controlling exhaust gas recirculation [EGR]
- F02D41/0065—Specific aspects of external EGR control
- F02D41/0072—Estimating, calculating or determining the EGR rate, amount or flow
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
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- F02D35/00—Controlling engines, dependent on conditions exterior or interior to engines, not otherwise provided for
- F02D35/02—Controlling engines, dependent on conditions exterior or interior to engines, not otherwise provided for on interior conditions
- F02D35/023—Controlling engines, dependent on conditions exterior or interior to engines, not otherwise provided for on interior conditions by determining the cylinder pressure
- F02D35/024—Controlling engines, dependent on conditions exterior or interior to engines, not otherwise provided for on interior conditions by determining the cylinder pressure using an estimation
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
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- F02D35/00—Controlling engines, dependent on conditions exterior or interior to engines, not otherwise provided for
- F02D35/02—Controlling engines, dependent on conditions exterior or interior to engines, not otherwise provided for on interior conditions
- F02D35/028—Controlling engines, dependent on conditions exterior or interior to engines, not otherwise provided for on interior conditions by determining the combustion timing or phasing
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
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- F02D41/00—Electrical control of supply of combustible mixture or its constituents
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- F02D41/0052—Feedback control of engine parameters, e.g. for control of air/fuel ratio or intake air amount
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- F02D41/1438—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor
- F02D41/1444—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases
- F02D41/1445—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the characteristics of the combustion gases the characteristics being related to the exhaust flow
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- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
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- F02P5/00—Advancing or retarding ignition; Control therefor
- F02P5/04—Advancing or retarding ignition; Control therefor automatically, as a function of the working conditions of the engine or vehicle or of the atmospheric conditions
- F02P5/145—Advancing or retarding ignition; Control therefor automatically, as a function of the working conditions of the engine or vehicle or of the atmospheric conditions using electrical means
- F02P5/15—Digital data processing
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02P—IGNITION, OTHER THAN COMPRESSION IGNITION, FOR INTERNAL-COMBUSTION ENGINES; TESTING OF IGNITION TIMING IN COMPRESSION-IGNITION ENGINES
- F02P5/00—Advancing or retarding ignition; Control therefor
- F02P5/04—Advancing or retarding ignition; Control therefor automatically, as a function of the working conditions of the engine or vehicle or of the atmospheric conditions
- F02P5/145—Advancing or retarding ignition; Control therefor automatically, as a function of the working conditions of the engine or vehicle or of the atmospheric conditions using electrical means
- F02P5/15—Digital data processing
- F02P5/1502—Digital data processing using one central computing unit
- F02P5/1516—Digital data processing using one central computing unit with means relating to exhaust gas recirculation, e.g. turbo
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02P—IGNITION, OTHER THAN COMPRESSION IGNITION, FOR INTERNAL-COMBUSTION ENGINES; TESTING OF IGNITION TIMING IN COMPRESSION-IGNITION ENGINES
- F02P9/00—Electric spark ignition control, not otherwise provided for
- F02P9/002—Control of spark intensity, intensifying, lengthening, suppression
- F02P9/005—Control of spark intensity, intensifying, lengthening, suppression by weakening or suppression of sparks to limit the engine speed
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/40—Engine management systems
Definitions
- the present invention relates to a control device for an internal combustion engine.
- a combustion control technology for improving the combustion performance of an internal combustion engine by recirculating (recirculating) part of the exhaust gas diverted from the exhaust pipe of the internal combustion engine to the intake pipe.
- this control technology while controlling the amount of air taken into the engine and the ratio of exhaust gas recirculation by the valve opening, the relationship between the amount of fresh air detected by the intake air amount sensor and the exhaust gas recirculation ratio is used.
- a system that controls the amount of fuel injection and ignition timing.
- a lean burn system that burns with a fuel mixture lean relative to the stoichiometric mixture ratio.
- the amount of air taken into the engine is controlled by the valve opening, and the fuel injection amount and ignition timing are adjusted based on the relationship between the amount of fresh air detected by the intake air amount sensor and the target air-fuel ratio.
- a controlled system is realized.
- the torsional vibration torque generated in the crank mechanism is estimated based on information on the crank angle and angular acceleration based on the crank angle sensor, and based on this, the dynamic relationship of the crank mechanism is calculated. It is disclosed to calculate the combustion pressure in the cylinder to be guided and use it for correction control of ignition timing and EGR rate.
- the method of calculating the in-cylinder combustion pressure using the dynamic relationship of the crank mechanism from the crank angle sensor information requires a large amount of calculation and requires high accuracy of the crank angle sensor. There was a problem that the cost of
- An object of the present invention is to provide a control device for an internal combustion engine that can detect the combustion state in a cylinder without using an in-cylinder sensor and reduce manufacturing costs.
- an internal combustion engine control apparatus of the present invention calculates a first combustion timing or a first combustion period in a cylinder of an internal combustion engine from a crank angle detected by a crank angle sensor, A heat release rate is calculated based on the combustion timing or the first combustion period, a cylinder pressure and a cylinder unburned gas temperature are calculated based on the heat release rate, and the cylinder pressure and the cylinder unburned gas temperature are calculated.
- a processor is provided that calculates a first combustion rate based on the gas temperature and learns a correspondence relationship between the first combustion rate and the first combustion timing or the first combustion period.
- the combustion state in the cylinder can be detected without using an in-cylinder sensor, and the manufacturing cost can be reduced. Problems, configurations, and effects other than those described above will be clarified by the following description of the embodiments.
- FIG. 1 is a schematic configuration diagram of an entire engine system to be controlled by an engine control system according to an embodiment of the present invention
- FIG. It is a block diagram which shows the hardware structural example of ECU.
- FIG. 5 is a diagram illustrating control blocks for calculating a throttle valve opening command value, an EGR valve opening command value, and a fuel injection valve driving pulse command value;
- FIG. 4 is a diagram for explaining an intake metering control block that calculates a current charging efficiency value and a current EGR rate value;
- FIG. 5 is a diagram illustrating control blocks for calculating a throttle valve opening command value, an EGR valve opening command value, and a fuel injection valve driving pulse command value
- FIG. 4 is a diagram for explaining an intake metering control block that calculates a current charging efficiency value and a current EGR rate value
- FIG. 4 is a diagram illustrating a physical model that is taken into account when constructing a throttle valve and an EGR valve opening degree control model that achieve a target charging efficiency and a target EGR rate; It is a figure explaining the method of calculating a target valve-opening degree based on a valve passage flow calculation model using a valve cross-sectional schematic diagram.
- FIG. 4 is a diagram illustrating an overview of a control block that corrects the fuel injection amount and the EGR valve opening based on the combustion state detected based on the crank angle sensor; 1 illustrates a typical heat release rate profile found in an engine and typical combustion duration/timing;
- FIG. FIG. 4 is a diagram illustrating a method of detecting MFB50 timing based on a crank angle sensor signal; FIG.
- FIG. 5 is a diagram showing the relationship between maximum angular acceleration and MFB50; It is a figure explaining the relationship between IG50 and IG10 and IG90. It is a figure explaining the heat release rate accompanying combustion.
- FIG. 4 is a diagram for explaining a method of calculating an in-cylinder pressure;
- FIG. 4 is a diagram illustrating a method of calculating an in-cylinder temperature and an unburned gas temperature; It is a figure explaining the relationship between a combustion speed and a combustion period.
- FIG. 4 is a diagram for explaining the effect of the difference in combustion period on the heat release rate;
- FIG. 4 is a diagram for explaining the effect of a difference in combustion period on in-cylinder pressure; It is a figure explaining the influence which the difference of a combustion period has on temperature.
- FIG. 3 is a diagram illustrating the effects of pressure, unburned gas temperature, and equivalence ratio (0.6) on the laminar burning velocity of gasoline.
- FIG. 3 is a diagram illustrating the effects of pressure, unburned gas temperature, and equivalence ratio (1.0) on the laminar burning velocity of gasoline.
- FIG. 3 is a diagram illustrating the effects of pressure, unburned gas temperature, and equivalence ratio (1.3) on the laminar burning velocity of gasoline.
- FIG. 4 is a diagram for explaining the effect of the EGR rate on the laminar burning speed of gasoline;
- FIG. 4 is a diagram explaining a method of learning the relationship between the combustion speed and the combustion period;
- FIG. 4 is a diagram for explaining a method for learning the relationship between the combustion speed and the combustion period based on the sequential least-squares algorithm and its flow chart.
- FIG. 5 is a diagram illustrating the tendency of IG50 with respect to rotational speed and charging efficiency;
- FIG. 4 is a diagram illustrating a flowchart relating to a combustion control method using combustion detection information based on a crank angle sensor in a lean burn system;
- FIG. 5 is a time chart for explaining behavior when combustion control is executed using combustion detection information based on a crank angle sensor in a lean burn system.
- FIG. 4 is a diagram illustrating a flowchart relating to a combustion control method using combustion detection information based on a crank angle sensor in an EGR system;
- FIG. 4 is a time chart for explaining behavior when combustion control is executed using combustion detection information based on a crank angle sensor in the EGR combustion system.
- the present embodiment aims to keep the EGR control accuracy and the air-fuel ratio at a high level, and prevent the combustion failure of the internal combustion engine due to these control errors.
- constituent elements having substantially the same function or configuration are denoted by the same reference numerals, and overlapping descriptions are omitted.
- FIG. 1 shows a schematic configuration example of the entire engine system to be controlled by the engine control system according to one embodiment of the present invention.
- the engine system includes an internal combustion engine 1, an accelerator position sensor 2, an air flow sensor 3, a throttle valve 4, an intake manifold 5, a flow enhancing valve 7, an intake valve 8, an exhaust valve 10, a fuel injection valve 12, a spark plug 13, and a crank angle.
- a sensor 20 is provided.
- the engine system includes an air-fuel ratio sensor 14, an EGR (Exhausted Gas Recirculation) pipe 15, an EGR cooler 16, an EGR temperature sensor 17, an EGR valve upstream pressure sensor 18, an EGR valve 19, and an ECU (Electronic Control Unit) 21. ing.
- EGR Extra Gas Recirculation
- the throttle valve 4 is provided upstream of the intake manifold 5 formed in the intake pipe 31 and controls the amount of intake air flowing into the cylinder of the internal combustion engine 1 by narrowing the intake passage.
- the throttle valve 4 is composed of an electronically controlled butterfly valve capable of controlling the valve opening degree independently of the amount of depression of the accelerator pedal by the driver.
- the downstream side of the throttle valve 4 communicates with an intake manifold 5 to which an intake pipe pressure sensor 6 is assembled.
- the flow enhancement valve 7 is arranged downstream of the intake manifold 5 and enhances turbulence of the flow inside the cylinder by creating a bias in the intake air taken into the cylinder. When exhaust gas recirculation combustion, which will be described later, is performed, the flow enhancement valve 7 is closed to promote and stabilize turbulent combustion.
- the internal combustion engine 1 is provided with an intake valve 8 and an exhaust valve 10 .
- the intake valve 8 and the exhaust valve 10 each have a variable valve mechanism for continuously varying the valve opening/closing phase.
- An intake valve position sensor 9 and an exhaust valve position sensor 11 for detecting the opening/closing phases of the valves are assembled to the variable valve mechanisms of the intake valve 8 and the exhaust valve 10, respectively.
- a cylinder of the internal combustion engine 1 is provided with a direct fuel injection valve 12 that injects fuel directly into the cylinder.
- the fuel injection valve 12 may be of a port injection type that injects fuel into the intake port.
- a spark plug 13 is attached to the cylinder of the internal combustion engine 1, with an electrode portion exposed inside the cylinder and igniting a combustible air-fuel mixture by a spark.
- the crank angle sensor 20 is attached to the crankshaft and outputs a signal corresponding to the rotation angle of the crankshaft to the ECU 21 as a signal indicating the rotation speed.
- the air-fuel ratio sensor 14 is provided in the exhaust pipe 32 and outputs a signal indicating the detected exhaust gas composition, that is, the air-fuel ratio, to the ECU 21 .
- an EGR system including an EGR pipe 15 and an EGR valve 19 arranged in the EGR pipe 15 is configured.
- the EGR pipe 15 connects the exhaust passage (intake pipe 31 ) and the intake passage (exhaust pipe 32 ), diverts the exhaust gas from the exhaust passage, and recirculates (recirculates) the exhaust gas downstream of the throttle valve 4 .
- An EGR cooler 16 provided in the EGR pipe 15 cools the exhaust gas.
- the EGR valve 19 is provided downstream of the EGR cooler 16 and controls the flow rate of exhaust gas.
- the EGR pipe 15 is provided with an EGR temperature sensor 17 that detects the temperature of exhaust gas flowing upstream of the EGR valve 19 and an EGR valve upstream pressure sensor 18 that detects the pressure upstream of the EGR valve 19 .
- the ECU 21 is an example of an electronic control device, and controls each component of the engine system and executes various data processing.
- An engine control system is configured by the engine system and the ECU 21 .
- Various sensors and various actuators described above are connected to the ECU 21 so as to be able to communicate with each other.
- the ECU 21 controls the operations of actuators such as the throttle valve 4, the fuel injection valve 12, the intake valve 8, the exhaust valve 10, the EGR valve 19, and the like.
- the ECU 21 also detects the operating state of the internal combustion engine 1 based on signals input from various sensors, and ignites the spark plug 13 at a timing determined according to the operating state. Furthermore, when the ECU 21 detects an abnormality or failure in the engine system including the internal combustion engine 1, the corresponding warning indicator lamp 22 (MIL) is lit.
- MIL warning indicator lamp 22
- FIG. 2 is a block diagram showing a hardware configuration example of the ECU 21.
- the ECU 21 includes a control section 23 , a storage section 24 and an input/output interface 25 which are interconnected via a system bus 26 .
- the control unit 23 is composed of a CPU (Central Processing Unit) 23a, a ROM (Read Only Memory) 23b, and a RAM (Random Access Memory) 23c.
- Each function of the ECU 21 is realized by the CPU 23a loading the control program stored in the ROM 23b into the RAM 23c and executing the program.
- a state space model, parameters, data obtained by executing a control program, and the like are recorded in a storage unit 24 as an auxiliary storage device made up of a semiconductor memory or the like.
- the control program may be stored in the storage unit 24 .
- the input/output interface 25 is an interface that communicates signals and data with each sensor and each actuator.
- the ECU 21 includes an A/D (Analog/Digital) converter (not shown) for processing input/output signals of each sensor, a driver circuit, and the like.
- the input/output interface 25 may also serve as an A/D converter.
- a CPU is used as the processor, other processors such as an MPU (Micro Processing Unit) may be used.
- FIG. 3 is a diagram illustrating control blocks for calculating the throttle valve opening command value, the EGR valve opening command value, and the fuel injection valve driving pulse command value.
- B is attached to the beginning of the code of each functional block (same below).
- the target torque calculation unit 301 calculates the target torque of the engine based on the rotational speed of the engine, the amount of depression of the accelerator pedal by the driver, and the externally requested torque.
- a target charging efficiency calculation unit 302 calculates charging efficiency, which is the amount of air taken into the cylinder in one cycle, based on the rotational speed and the target torque.
- the charging efficiency is the ratio of the amount of air that is actually taken in, with the air mass when the stroke volume is filled with air in a standard state (25° C., 1 atm) as a reference of 1.0.
- the target throttle valve opening calculation unit 303 calculates the air flow rate passing through the throttle valve based on the target charging efficiency and rotation speed, and calculates the target throttle valve opening degree that realizes the above air flow rate from the throttle front and rear states. A throttle valve opening command value is output based on this target throttle valve opening.
- the target EGR rate calculation unit 304 an EGR rate that is adjusted in advance to suit the engine in consideration of fuel consumption and exhaust performance is set in a control map for each rotation speed and target charging efficiency.
- a target EGR rate is calculated based on the speed and the target charging efficiency.
- a target EGR valve opening degree calculation unit 305 calculates a target EGR valve opening degree based on the current charging efficiency value, the rotation speed, the target EGR rate, and a combustion speed prediction result, which will be described later.
- An EGR valve opening command value is output based on this target EGR valve opening. Details of the current charging efficiency value will be described later with reference to FIG.
- the target equivalence ratio calculation unit 306 calculates the target equivalence ratio based on the target charging efficiency and the rotation speed.
- the equivalence ratio is an index of the fuel air-fuel mixture concentration based on the theoretical air-fuel ratio.
- a target fuel injection amount calculation unit 307 calculates a target fuel injection amount based on the current charging efficiency value, the target equivalence ratio, and a combustion speed prediction result, which will be described later. An injector drive pulse command value is output based on this fuel injection amount.
- the fuel center-of-gravity timing calculator 308 calculates the combustion center-of-gravity timing (MFB50: 50% Mass Fraction Burned) based on the crank angle sensor signal.
- a combustion speed prediction unit 309 predicts the combustion speed based on the timing of the center of gravity of combustion, the rotation speed, the current charging efficiency value, the current EGR rate value, and the current equivalence ratio value.
- the target EGR rate and the target fuel injection amount are corrected based on the combustion speed prediction result or the combustion period prediction result that has a correlation with the combustion speed. Details of the EGR rate current value will be described later with reference to FIG.
- FIG. 4 is a diagram illustrating an intake metering control block that calculates the current charging efficiency value and the current EGR rate value.
- the EGR valve passage flow rate calculation section 401 calculates the EGR valve passage flow rate based on the EGR valve opening degree, the EGR valve upstream state, and the EGR valve downstream state.
- the EGR valve upstream state can be detected directly by a pressure sensor and a temperature sensor, or a calculated value by a control map can be applied based on engine speed and load information.
- An intake pipe pressure, temperature and EGR rate calculation unit 402 calculates the intake pipe pressure, temperature and EGR rate based on the cylinder intake flow rate, the sensor value of the air flow sensor and the EGR valve passage flow rate.
- a charging efficiency/EGR rate calculation unit 403 calculates and outputs the current values of the charging efficiency and EGR rate based on the intake pipe pressure, temperature, EGR rate, and rotation speed.
- a cylinder intake flow rate calculation unit 404 calculates a cylinder intake flow rate based on the rotational speed, the charging efficiency, the EGR rate, and the rotational speed.
- FIG. 5 is a diagram explaining a physical model that is taken into account when constructing a throttle valve and EGR valve opening degree control model that achieves the target charging efficiency and the target EGR rate.
- the pressure in the intake pipe for example, the intake manifold 5
- intake pipe pressure the pressure in the intake pipe
- EGR rate ⁇ m in the intake pipe the EGR rate ⁇ m in the intake pipe
- mth with a superscript dot symbol is the flow rate through the throttle valve
- megr with a superscript dot symbol is the EGR valve flow rate
- mcyl with a superscript dot symbol is the cylinder intake flow rate
- ⁇ is the polytropic index
- R is the gas constant.
- Vm is the intake manifold volume
- Ta is the atmospheric temperature
- Tegr is the EGR temperature
- Tm is the intake pipe internal temperature.
- the superscript dot symbol represents the first derivative with respect to time.
- the flow rate through the throttle valve (mth with superscript dot symbol) can be obtained by the following formula (3).
- the throttle valve passing flow rate roughly corresponds to the detected value of the airflow sensor 3 (mafs with a superscript dot symbol).
- ⁇ a is the air density
- ⁇ th is the throttle valve flow coefficient
- Dth is the throttle valve outer diameter
- ⁇ th is the throttle valve opening
- ⁇ th0 is the throttle valve minimum opening
- pa is the atmospheric pressure.
- the EGR valve passage flow rate (megr with a superscript dot symbol) can be obtained by the following formula (4).
- ⁇ e is the EGR density (recirculated exhaust gas density)
- ⁇ egr is the EGR valve flow coefficient
- Degr is the EGR valve outer diameter
- ⁇ egr is the EGR valve opening
- ⁇ egr0 is the EGR valve minimum opening.
- the cylinder intake flow rate (mcyl with a superscript dot symbol) is obtained by the following equation (5).
- Ne is the rotational speed of the internal combustion engine 1 (the number of revolutions per minute)
- ⁇ in is the intake efficiency
- Vd is the total stroke volume of the internal combustion engine 1 .
- the intake efficiency is a value that indicates the ratio of the mass of gas actually sucked into the cylinders, with the mass of gas in the intake manifold corresponding to the stroke volume of all cylinders (for example, 4 cylinders) as the standard (1.0). is.
- the charging efficiency ⁇ ch of fresh air sucked into the cylinder is defined by the following equation (6).
- p0 and T0 are the temperature and pressure (for example, 25°C, 101.325 Pa) in the standard state of the atmosphere.
- the net mean effective pressure which is an index of torque, is obtained by the following formula (7).
- HL is the lower calorific value of the fuel
- ⁇ ite is the indicated thermal efficiency
- ⁇ is the equivalence ratio
- L0 is the stoichiometric air-fuel ratio
- pf is the friction mean effective pressure related to friction torque.
- Friction torque is torque that acts to inhibit motion between bodies that are in frictional contact.
- FIG. 6 is a diagram illustrating a method of calculating the target valve opening degree based on the valve passage flow calculation model, using a valve cross-sectional schematic diagram.
- m with a superscript dot in the figure is the flow rate through the valve
- pup is the gas pressure on the upstream side (in) of the valve
- pdown is the gas pressure on the downstream side (out) of the valve
- ⁇ up is the gas on the upstream side of the valve.
- D is the outer diameter of the valve
- ⁇ is the opening of the valve.
- the shaded area represents the gas flow path through the valve.
- the cross-sectional area of the flow path, that is, the opening area S is represented by the following equation (8).
- the above equation (9) can be replaced with a table calculation of the throttle valve opening and the opening area, and used for calculation of the target throttle valve opening by the target throttle valve opening calculator 503 in FIG.
- pup in FIG. 6 corresponds to the EGR valve upstream pressure pegr, pdown to the intake pipe pressure pm, ⁇ up to the EGR density ⁇ egr, and D to the EGR valve outer diameter Degr.
- the EGR valve opening degree ⁇ egr for realizing the target EGR flow rate (megr, d with a superscript dot symbol) defined by the target torque and rotation speed by modifying the EGR valve passage flow rate formula of formula (4) is It is obtained by back calculating the EGR valve passage flow rate formula as shown in the following formula (10).
- the above equation (10) can be replaced with a table calculation of the EGR valve opening and the opening area, and used for calculation of the target EGR valve opening by the target EGR rate calculation unit 504 in FIG.
- FIG. 7 is a diagram illustrating an overview of control blocks that correct the fuel injection amount and the EGR valve opening based on the combustion state detected based on the crank angle sensor.
- a charging efficiency/EGR rate calculation unit 701 calculates the current charging efficiency and EGR rate based on the rotation speed, the sensor value of the airflow sensor, the throttle valve opening, and the EGR valve opening. The model calculated by the same calculation unit is explained in detail in FIGS. 5 and 4. FIG.
- the heat release rate calculation unit 702 calculates the heat release rate based on the current charging efficiency, EGR rate, equivalence ratio, and combustion period described later.
- the heat release rate is the amount of heat generated per crank angle out of the total amount of heat generated by combustion.
- the heat release rate profile varies depending on the combustion speed, combustion chamber shape, ignition timing, and other factors.
- the in-cylinder pressure, in-cylinder temperature, and unburned gas temperature calculation unit 703 the in-cylinder pressure, in-cylinder temperature, and unburned gas temperature are calculated from the equation of state and the polytropic change relational expression from the relationship between the heat release rate and the combustion chamber volume described above. Desired.
- a laminar combustion speed calculator 704 calculates the laminar combustion speed from the in-cylinder pressure, unburned gas temperature, equivalence ratio, and EGR rate.
- the laminar burning velocity is a state quantity determined by fuel type, mixture composition, temperature and pressure.
- the MFB50 calculation unit calculates MFB50, which is the timing at which the combustion mass ratio reaches 50% of the total supplied mass (combustion center of gravity timing) based on the crank angle sensor signal.
- a combustion period calculator 706 calculates the total combustion period from the ignition timing to the combustion end timing based on the correlation with the MFB50.
- the combustion speed/combustion period learning unit 707 learns the relationship between the information on the combustion period obtained from the crank angle sensor signal (crank angle sensor information) and the laminar combustion speed based on the in-cylinder pressure estimation. For learning, a sequential least squares algorithm, which will be described later, is applied. Since it can be learned on-board by a sequential least squares algorithm, vehicle-specific correlations can be taken into account in the control. Causes of vehicle-specific conditions include variations in fuel properties, changes in fuel type (for example, alcohol concentration in fuel), EGR valve and throttle valve deposition, actuator/sensor errors, and the like.
- a laminar combustion speed prediction unit 708 predicts the laminar combustion speed in the target control state based on the target equivalence ratio, target EGR rate, current in-cylinder pressure, and unburned gas temperature.
- the combustion period prediction unit 709 calculates the target equivalence ratio, the target EGR rate, the current in-cylinder pressure, and the combustion period for the unburned gas temperature based on the above-mentioned laminar flow combustion speed prediction result and the correlation between the combustion speed and the combustion period. to predict.
- the target equivalence ratio/target EGR rate correction unit 710 corrects the target equivalence ratio or the target EGR rate to the side where the combustion period decreases (the side where the combustion speed increases) when the combustion period prediction value becomes equal to or greater than a predetermined value. correct. That is, in the equivalence ratio, when the combustion period exceeds a predetermined value, correction to the rich side is performed. In the fuel injection amount correction amount calculation unit 711, the fuel injection amount corresponding to the rich correction is corrected to the increase side, and the correction amount is added to the injector pulse width command value.
- the target value is corrected to reduce the EGR.
- the EGR valve opening correction amount calculation unit 712 the EGR valve opening correction amount corresponding to the EGR reduction correction is added to the EGR valve opening command value.
- An ignition advance correction amount calculator 713 advances the ignition timing when the combustion period increases, and retards the ignition timing when the combustion period decreases. Ignition timing is output as a command value.
- Fig. 8 is a diagram explaining a typical heat release rate profile seen in an engine and typical combustion periods/timings.
- Combustion in a gasoline engine is in the flame nucleus formation period for some time after ignition and produces little heat release.
- the period up to the 10% combustion mass fraction timing (MFB10) is called an initial combustion period.
- the period from the ignition timing to MFB10 is called IG10.
- the period from MFB10 to MFB90, in which combustion progresses due to turbulent flame propagation and exhibits most of the heat release rate, is called the main combustion period.
- MFB50 is defined as the timing of the combustion center of gravity, and this MFB50 timing is detected based on the crank angle sensor signal.
- FIG. 9A and 9B are diagrams explaining a method of detecting the MFB50 timing based on the crank angle sensor signal.
- FIG. 9A shows the results of the crankshaft angular acceleration obtained based on the crank angle sensor signal versus the crank angle.
- the angular acceleration of the crankshaft shows a peak at the combustion timing of each cylinder.
- the figure below shows the relationship between the maximum crank angular acceleration and the combustion center of gravity (MFB50) of each cylinder.
- MFB50 combustion center of gravity
- the system of the embodiment of the present invention is configured to detect MFB50, which is the combustion center of gravity, but the present invention is not limited to this, and the same can be done by detecting other combustion mass ratios as representatives. or a similar effect.
- FIG. 10 is a diagram explaining the relationship between IG50 and IG10 and IG90.
- IG50 is the combustion period from ignition timing to MFB50, and MFB50 based on the crank angle sensor signal described above can be applied.
- MFB50 based on the crank angle sensor signal described above
- Information on the initial combustion period can be obtained from IG10, information on the entire combustion period from IG90, and information on the main combustion period from information on MFB10 to MFB90.
- the system of the embodiment of the present invention is configured to use linear functions of IG50, IG10, and IG90, but the present invention is not limited to this, and the use of quadratic functions etc. is also possible. or a similar effect.
- Figures 11A, 11B, and 11C are diagrams explaining a method of calculating the in-cylinder pressure, the in-cylinder temperature, and the unburned gas temperature from the heat release rate associated with combustion.
- the pressure and temperature in the cylinder at the intake valve closing timing (IVC) are obtained based on the pressure and temperature in the intake pipe.
- the pressure and temperature in the cylinder at the ignition timing are obtained by the following equations, assuming the state change from IVC to the ignition timing (SPK) as a polytropic change.
- ⁇ is the polytropic index, which is determined by the specific heat ratio and heat loss depending on the temperature and gas composition.
- Vz is the cylinder volume corresponding to the crank angle.
- n -th in-cylinder temperature Tzn is obtained by the following equation.
- ⁇ is the crank angle
- Qz is the amount of heat generated.
- An empirical formula called the Wiebe function can be applied to dQz/d ⁇ .
- a table operation that stores the results of pre-calculating the Wiebe function may be used.
- n-th unburned gas temperature Tu n is obtained by the following equation based on the pressure and temperature at the ignition timing and the n -th in-cylinder pressure Pzn.
- Figures 12A to 12D are diagrams for explaining the relationship between the combustion speed and the combustion period, and the influence of the difference in the combustion period on the in-cylinder pressure and temperature.
- the relationship between the combustion speed and the combustion period is generally inversely proportional, and the combustion period increases as the combustion speed decreases.
- the effect of the combustion period on the in-cylinder pressure the shorter the combustion period, the more the in-cylinder pressure increases. Also, the in-cylinder pressure temperature and the unburned gas temperature tend to increase as the combustion period becomes shorter.
- the cylinder pressure and temperature are affected by changes in the combustion speed, and the combustion speed itself is also affected by the pressure and temperature. is difficult in principle. Therefore, in order to control the EGR rate, air-fuel ratio and ignition timing based on the combustion speed and combustion duration, means for predicting the combustion speed and combustion duration are required.
- the prediction means the system of the embodiment of the present invention is equipped with learning means for the combustion speed and combustion period, and is configured to perform present or future prediction based on past learning results.
- Figures 13A, 13B, and 13C are diagrams for explaining the effects of pressure, unburned gas temperature, and equivalence ratio on the laminar burning velocity of gasoline.
- the pressure ratio/temperature ratio is the ratio to the standard atmospheric pressure and atmospheric temperature. Both pressure, unburned gas temperature and equivalence ratio affect the laminar burning velocity, and their sensitivities vary under the influence of interactions.
- the laminar burning velocity can be obtained based on the pressure, unburned gas temperature and equivalence ratio.
- FIG. 14 is a diagram explaining the effect of the EGR rate on the laminar burning speed of gasoline.
- the vertical axis in the figure is the laminar flow combustion speed ratio with the condition of zero EGR rate being 1.0 as a reference, and indicates the sensitivity to the EGR mole fraction.
- the laminar combustion velocity decreases as the EGR rate increases.
- FIG. 15 is a diagram explaining a method of learning the relationship between the combustion speed and the combustion period.
- a method of learning by approximating the above relationship with a polynomial is adopted. Since the burning speed is affected by turbulence in addition to the laminar burning speed, rotational speed and charging efficiency are considered when learning the relationship between the burning speed and the burning period. Furthermore, since the combustion mechanism differs between the initial combustion period (ignition timing to MFB10) and the main combustion period (MFB10 to MFB90), the laminar combustion velocity in both periods is considered. Define the following polynomial with these variables.
- x1 is the rotation speed
- x2 is the charging efficiency
- x3 is the laminar burning velocity in the initial combustion period
- x4 is the laminar burning velocity in the main combustion period.
- FIG. 16 is a diagram explaining a method and its flowchart for learning the relationship between the combustion speed and the combustion period based on the sequential least squares algorithm.
- a method for sequentially updating the partial regression coefficient vector ⁇ based on the relationship between input and output will be shown. Note that the partial regression coefficient vector is indicated by adding the symbol ⁇ above (or in the upper right) of ⁇ .
- S1601 it is determined whether the sequential least-squares algorithm can be executed. As a judgment index of the feasibility, the sensor state and the prediction range of the premise state equation are taken into consideration.
- the arithmetic expressions executed in S1602 to S1606 are specifically shown below.
- the relationship between the combustion period and the combustion speed targeted here is a time-varying system that is affected by fuel properties, deposition of deposits, and actuator/sensor errors.
- the forgetting factor is a function that exponentially reduces the impact of past data. Furthermore, by making variable forgetting, the past data is forgotten in the transient state, while the forgetting factor approaches 1 in the steady state. can be actively used.
- the following is a sequential least-squares algorithm with a variable forgetting factor. First, the difference between the polynomial and the output value is calculated as the error ⁇ (k) by the following equation (S1602).
- the forgetting factor ⁇ (k) and the covariance matrix P(k) are obtained by the following equations (S1605, S1606).
- ⁇ is an adjustment parameter during learning.
- a sequential least-squares algorithm is employed as the parameter identification algorithm of this embodiment, the present invention is not limited to this. That is, even if other optimization methods such as genetic algorithms are applied as the parameter identification algorithm, similar or similar effects can be obtained.
- FIG. 17 is a diagram explaining the tendency of IG50 with respect to rotational speed and charging efficiency.
- IG50 is affected by an increase in the residual gas ratio and a decrease in pressure/temperature conditions, etc. under low-load conditions where the charging efficiency decreases, and as a result, the laminar combustion velocity during the initial combustion period decreases, resulting in an increase in IG50. tend to On the other hand, as the rotation speed increases, the turbulence intensity increases and the turbulent combustion speed also increases. tend to be less.
- Equation (16) The tendency of IG50 with respect to the rotational speed and charging efficiency described above is approximated by equation (16).
- EGR combustion when EGR is affected by deposits and changes to the increasing side with respect to the same EGR valve opening, IG50 changes to the increasing side.
- lean burn when the laminar combustion speed decreases with respect to the same target equivalence ratio due to the influence of fuel properties and fuel type, IG50 changes to the increasing side.
- Adaptive control by on-board learning is possible even for such engine-to-engine changes by employing equation (16) and iterative least-squares approximation of the partial regression coefficients of the same model.
- FIG. 18 is a diagram explaining a flowchart relating to a combustion control method using combustion detection information based on a crank angle sensor in a lean burn system.
- the target torque is calculated based on the amount of depression of the accelerator pedal by the driver.
- the charging efficiency for realizing the target torque is calculated.
- the throttle valve opening that realizes the amount of air required for the engine is calculated.
- the target equivalence ratio is calculated based on the rotational speed and charging efficiency.
- the injector fuel injection pulse width that achieves the target equivalence ratio is calculated.
- MFB50 is detected based on the crank angle sensor signal.
- each combustion period such as the initial combustion period, the main combustion period, and the total combustion period is calculated from the MFB50 and the ignition timing.
- the in-cylinder pressure, temperature and unburned gas temperature with respect to the crank angle are calculated.
- the laminar flow combustion velocity for each period is calculated based on the in-cylinder pressure, unburned gas temperature, EGR rate, and equivalence ratio corresponding to the initial combustion period and main combustion period described above.
- S1810 whether or not learning is possible is determined in consideration of whether the sensor is in a steady state or not, and if it is determined that learning is possible, in S1811 a statistical model relating to the combustion speed and combustion period is learned.
- S1812 the combustion speed at the target equivalence ratio (lean in the example of FIG. 18) is predicted.
- the combustion period is predicted using the statistical model described above based on the predicted combustion speed.
- S1815 based on the predicted combustion period, if the combustion period is greater than a predetermined value, in S1815 the equivalence ratio is corrected to the rich side.
- FIG. 19 is a time chart for explaining the behavior when combustion control is executed using combustion detection information based on a crank angle sensor in a lean burn system.
- FIG. 20 is a diagram explaining a flowchart relating to a combustion control method using combustion detection information based on a crank angle sensor in the EGR system.
- the target torque is calculated based on the amount of depression of the accelerator pedal by the driver.
- the charging efficiency for realizing the target torque is calculated.
- the throttle valve opening that realizes the amount of air required for the engine is calculated.
- the target EGR rate is calculated based on the rotation speed and charging efficiency.
- the EGR valve opening that achieves the target equivalence ratio is calculated.
- MFB50 is detected based on the crank angle sensor signal.
- each combustion period such as the initial combustion period, the main combustion period, and the total combustion period is calculated from the MFB50 and the ignition timing.
- S2010 it is determined whether or not learning is possible in consideration of whether the sensor is in a steady state or not, and if it is determined that learning is possible, in S2011 a statistical model relating to the combustion speed and combustion period is learned.
- S2012 the combustion speed at the target EGR rate is predicted.
- S2013 the combustion period is predicted using the statistical model described above based on the predicted combustion speed.
- S2014 based on the predicted combustion period, if the combustion period is greater than a predetermined value, the EGR rate is corrected to be reduced in S2015.
- FIG. 21 is a time chart for explaining the behavior when combustion control is executed using combustion detection information based on the crank angle sensor in the EGR combustion system.
- the electronic control unit (ECU 21) includes an EGR pipe (EGR pipe 15) that recirculates part of the exhaust gas of the internal combustion engine to the intake pipe and an EGR valve (EGR valve) arranged in the EGR pipe.
- EGR pipe 15 EGR pipe 15
- EGR valve EGR valve
- an air flow sensor air flow sensor 3 that detects the flow rate of air taken into the intake pipe
- a throttle valve throttle valve 4
- the throttle an intake pipe pressure sensor (intake pipe pressure sensor 6) provided downstream of the valve and downstream of a connecting portion between the intake pipe and the EGR pipe for detecting the intake pipe pressure, which is the pressure downstream of the throttle valve in the intake pipe
- a crank angle sensor for detecting rotation speed, combustion center-of-gravity timing (MFB50), and the like, for controlling an engine.
- This electronic control unit calculates the in-cylinder pressure, temperature and unburned gas temperature based on the combustion period calculated based on the MFB50 detected by the crank angle sensor, and equivalence ratio and EGR means for calculating the combustion speed from the rate, learning the correlation between the combustion period and the combustion speed, and correcting the target values of the EGR rate and the equivalence ratio based on the learned correlation.
- a sequential least squares algorithm is applied to at least the learning unit.
- the combustion speed excessively decreases and the combustion period becomes long, resulting in unstable combustion.
- the present invention is not limited to the above-described embodiments, and it goes without saying that various other application examples and modifications are possible as long as they do not depart from the gist of the present invention described in the claims.
- the above-described embodiments are detailed and specific descriptions of the configurations of the electronic control unit and the engine control system in order to explain the present invention in an easy-to-understand manner, and are not necessarily limited to those having all the components described. .
- the present invention is not limited to this example.
- the present invention can be applied to an engine system with a supercharger.
- each configuration, function, processing unit, etc. of the above embodiments may be implemented in hardware by designing, for example, an integrated circuit in part or in whole.
- an FPGA Field Programmable Gate Array
- an ASIC Application Specific Integrated Circuit
- a plurality of processes may be executed in parallel or the order of the processes may be changed as long as the processing results are not affected.
- the processors (B705, B706, FIG. 7) of the control device (ECU 21, FIG. 2) of the internal combustion engine 1 determine the first combustion timing (MFB50) or A first combustion period (IG100_1) is calculated. In this embodiment, the processor calculates the first combustion period (IG100_1) after calculating the first combustion timing (MFB50). good too.
- the processor (B702) calculates the heat release rate based on the first combustion timing (MFB50) or the first combustion period (IG100_1).
- the processor (B703) calculates the in-cylinder pressure and the in-cylinder unburned gas temperature based on the heat release rate.
- a processor (B704) calculates a first combustion speed (laminar combustion speed SL1) based on the in-cylinder pressure and the in-cylinder unburned gas temperature.
- the processor (B707) learns the correspondence relationship between the first burning speed (laminar burning speed SL1) and the first burning period (IG100_1). In this embodiment, the processor (B707) learns the correspondence relationship between the first burning speed (laminar combustion speed SL1) and the first combustion period (IG100_1). The correspondence relationship between the speed SL1) and the first combustion timing (MFB50) may be learned. This makes it possible to adapt to variations in correspondence caused by vehicle-specific usage environments (fuel, in-vehicle equipment, sensors, actuators, etc.).
- the processor controls the second combustion speed (laminar flow Estimate the burning speed SL2). As a result, the burning speed (laminar flow burning speed SL2) at which the control parameter becomes the target value can be obtained.
- the processors (B709, B710) correct the target values (target equivalence ratio, target EGR rate) of the control parameters of the internal combustion engine based on the predicted second combustion speed (laminar combustion speed SL2). As a result, feedback control can be performed without using an in-cylinder sensor.
- the processor (B709) predicts the second combustion period (IG100_2) corresponding to the second combustion speed (laminar combustion speed SL2) from the learned correspondence.
- the processor (B709) may predict the second combustion timing corresponding to the second combustion speed (laminar combustion speed SL2) instead of predicting the second combustion period (IG100_2).
- the combustion period (IG100_2) or the combustion timing in which the control parameter becomes the target value in the use environment of each vehicle can be acquired.
- the processor (B710) corrects the target values of the control parameters (target equivalence ratio, target EGR rate) of the internal combustion engine 1 based on the second combustion period (IG100_2).
- the processor (B710) may correct the target values (target equivalence ratio, target EGR rate) of the control parameters of the internal combustion engine 1 based on the predicted second combustion timing. As a result, feedback control can be performed without using an in-cylinder sensor.
- the control parameters are, for example, the EGR rate, the EGR valve opening, the air-fuel ratio, the fuel injection period indicating the driving pulse width of the injector, the ignition timing, the ignition energy, or the opening of the flow enhancement valve that causes the intake air to drift. .
- Ignition energy is controlled by, for example, changing the energization time of the ignition plug.
- the processor (B707) may stop learning the correspondence depending on the operating state of the internal combustion engine 1 or the operating state of the actuators or sensors mounted on the internal combustion engine 1. For example, immediately after the ECU 21 is started, the learning of the correspondence relationship is stopped in a state where the detected values of the sensors are fluctuating. This improves the accuracy of learning.
- the processor calculates the first burning speed (laminar burning speed SL1) based on the learning result of the correspondence relationship between the first burning speed (laminar burning speed SL1) and the first combustion timing or the first burning period (IG100_1). , the first combustion timing (MFB50) or the first combustion period (IG100_1) and a threshold value for determining the failure state may be compared, and the failure may be diagnosed based on the comparison result. As a result, failure can be determined without using an in-cylinder sensor.
- the processor may predict the period until the failure state based on the temporal change in the learning result of the correspondence relationship and the threshold value for determining the failure state. This allows, for example, the user to perform maintenance on the internal combustion engine or the control device in consideration of the period leading up to the predicted failure state.
- a control device for an internal combustion engine 1 comprising a crank angle sensor 20 for detecting a crank angle on the crankshaft of the internal combustion engine 1, and means for detecting combustion timing (MFB50) in a cylinder based on the crank angle sensor detection value.
- ECU 21 means for calculating an in-cylinder pressure and an in-cylinder unburned gas temperature based on the information on the combustion timing (B703); , means for calculating the combustion speed (B704), and means for learning the relationship between the calculated combustion speed and the detected combustion timing or combustion period (B707).
- control apparatus for an internal combustion engine comprising means (B708) for predicting the combustion speed based on target values (target equivalence ratio, target EGR rate, etc.) of control parameters of the internal combustion engine.
- a control device for an internal combustion engine characterized by:
- the internal combustion engine control apparatus further comprising means (B710) for correcting a target value of a control parameter of the internal combustion engine based on the predicted combustion speed. controller.
- a control device for an internal combustion engine comprising means (B708, B709) for predicting combustion timing or combustion period based on the predicted combustion speed.
- control apparatus for an internal combustion engine characterized by comprising means (B710) for correcting target values of control parameters of the internal combustion engine based on the predicted combustion timing or combustion period.
- a control device for an internal combustion engine is characterized by comprising
- control device for an internal combustion engine according to any one of (3) to (5), wherein the control parameter is an EGR rate or an EGR valve opening.
- control device for an internal combustion engine according to any one of (3) to (5), wherein the control parameter is an air-fuel ratio or an injector injection period.
- control device for an internal combustion engine according to any one of (3) to (5), wherein the control parameter is ignition timing or ignition energy.
- control device for an internal combustion engine according to any one of (3) to (5), wherein the control parameter is the degree of opening of a flow enhancement valve.
- control device for an internal combustion engine wherein the combustion speed, the combustion timing or the combustion period and the abnormal state are determined based on the learning result of the relationship between the combustion speed and the combustion timing or the combustion period.
- a control apparatus for an internal combustion engine comprising an abnormality diagnosis means for comparing a threshold value for the internal combustion engine and diagnosing an abnormality based on the comparison result.
- control device for an internal combustion engine based on the learning result of the relationship between the combustion speed and the combustion timing or the combustion period, for determining the temporal change of the learning result and the abnormal state.
- a control apparatus for an internal combustion engine comprising an abnormality diagnosis means for predicting a period until the learning value reaches an abnormal state based on a threshold value.
- the relationship between the in-cylinder combustion speed and the combustion period is learned based on the combustion center-of-gravity timing detected based on the crank angle sensor, and based on the relationship, EGR control or air-fuel ratio control is performed. is corrected.
- EGR control or air-fuel ratio control is performed. is corrected.
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- Combined Controls Of Internal Combustion Engines (AREA)
Abstract
Description
である。
プロセッサは、第1燃焼速度(層流燃焼速度SL1)と、第1燃焼タイミング又は第1燃焼期間(IG100_1)との対応関係の学習結果に基づいて、第1燃焼速度(層流燃焼速度SL1)、第1燃焼タイミング(MFB50)又は第1燃焼期間(IG100_1)と、故障状態を判定するための閾値とを比較し、比較結果に基づいて故障を診断してもよい。これにより、筒内センサを用いることなく、故障を判定することができる。
Claims (8)
- クランク角度センサによって検出されたクランク角度から内燃機関の筒内の第1燃焼タイミング又は第1燃焼期間を演算し、
前記第1燃焼タイミング又は第1燃焼期間に基づいて、熱発生率を演算し、
前記熱発生率に基づいて、筒内圧力と筒内未燃ガス温度を演算し、
前記筒内圧力と前記筒内未燃ガス温度に基づいて、第1燃焼速度を演算し、
前記第1燃焼速度と、前記第1燃焼タイミング又は前記第1燃焼期間との対応関係を学習するプロセッサを備える内燃機関の制御装置。 - 請求項1に記載の内燃機関の制御装置であって、
前記プロセッサは、
前記内燃機関のフィードバック制御の制御パラメータの目標値に基づいて、前記制御パラメータが前記目標値となる状態の第2燃焼速度を予測する
ことを特徴とする内燃機関の制御装置。 - 請求項2に記載の内燃機関の制御装置であって、
前記プロセッサは、
予測された前記第2燃焼速度に基づいて、前記内燃機関の前記制御パラメータの前記目標値を補正する
ことを特徴とする内燃機関の制御装置。 - 請求項2に記載の内燃機関の制御装置であって、
前記プロセッサは、
学習された前記対応関係から、前記第2燃焼速度に対応する第2燃焼タイミング又は第2燃焼期間を予測する
ことを特徴とする内燃機関の制御装置。 - 請求項4に記載の内燃機関の制御装置であって、
前記プロセッサは、
前記第2燃焼タイミング又は前記第2燃焼期間に基づいて、前記内燃機関の制御パラメータの目標値を補正する
ことを特徴とする内燃機関の制御装置。 - 請求項2に記載の内燃機関の制御装置であって、
前記制御パラメータは、
EGR率、EGR弁開度、
空燃比、インジェクタの駆動パルス幅を示す燃料噴射期間、
点火時期、点火エネルギ、又は
吸入空気に偏流を生じさせる流動強化弁の開度である
ことを特徴とする内燃機関の制御装置。 - 請求項1に記載の内燃機関の制御装置であって、
前記プロセッサは、
前記内燃機関の運転状態又は、前記内燃機関に搭載されるアクチュエータ若しくはセンサの動作状態に応じて、前記対応関係の学習を停止する
ことを特徴とする内燃機関の制御装置。 - 請求項1に記載の内燃機関の制御装置であって、
前記プロセッサは、
前記対応関係の学習結果に基づいて、前記第1燃焼速度、前記第1燃焼タイミング又は前記第1燃焼期間と、故障状態を判定するための閾値とを比較し、比較結果に基づいて故障を診断し、又は
前記対応関係の学習結果の時間的変化と、故障状態を判定するための閾値とに基づいて、故障状態に至るまでの期間を予測する
ことを特徴とする内燃機関の制御装置。
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JP2023516278A JP7431381B2 (ja) | 2021-04-19 | 2022-01-25 | 内燃機関の制御装置 |
US18/280,285 US20240068423A1 (en) | 2021-04-19 | 2022-01-25 | Control Device for Internal Combustion Engine |
CN202280019528.6A CN116981841A (zh) | 2021-04-19 | 2022-01-25 | 内燃机的控制装置 |
DE112022000517.3T DE112022000517T5 (de) | 2021-04-19 | 2022-01-25 | Steuereinrichtung für brennkraftmaschine |
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US20240068423A1 (en) | 2024-02-29 |
CN116981841A (zh) | 2023-10-31 |
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