WO2001046569A1 - Régulateur de rapport air-carburant de moteurs thermiques - Google Patents
Régulateur de rapport air-carburant de moteurs thermiques Download PDFInfo
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- WO2001046569A1 WO2001046569A1 PCT/JP2000/009116 JP0009116W WO0146569A1 WO 2001046569 A1 WO2001046569 A1 WO 2001046569A1 JP 0009116 W JP0009116 W JP 0009116W WO 0146569 A1 WO0146569 A1 WO 0146569A1
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- fuel ratio
- air
- value
- deterioration
- catalyst device
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/02—Circuit arrangements for generating control signals
- F02D41/14—Introducing closed-loop corrections
- F02D41/1438—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor
- F02D41/1439—Introducing closed-loop corrections using means for determining characteristics of the combustion gases; Sensors therefor characterised by the position of the sensor
- F02D41/1441—Plural sensors
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- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/02—Circuit arrangements for generating control signals
- F02D41/14—Introducing closed-loop corrections
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N11/00—Monitoring or diagnostic devices for exhaust-gas treatment apparatus, e.g. for catalytic activity
- F01N11/007—Monitoring or diagnostic devices for exhaust-gas treatment apparatus, e.g. for catalytic activity the diagnostic devices measuring oxygen or air concentration downstream of the exhaust apparatus
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/02—Circuit arrangements for generating control signals
- F02D41/021—Introducing corrections for particular conditions exterior to the engine
- F02D41/0235—Introducing corrections for particular conditions exterior to the engine in relation with the state of the exhaust gas treating apparatus
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- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/02—Circuit arrangements for generating control signals
- F02D41/14—Introducing closed-loop corrections
- F02D41/1401—Introducing closed-loop corrections characterised by the control or regulation method
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/02—Circuit arrangements for generating control signals
- F02D41/14—Introducing closed-loop corrections
- F02D41/1401—Introducing closed-loop corrections characterised by the control or regulation method
- F02D41/1403—Sliding mode control
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N2550/00—Monitoring or diagnosing the deterioration of exhaust systems
- F01N2550/02—Catalytic activity of catalytic converters
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/02—Circuit arrangements for generating control signals
- F02D41/14—Introducing closed-loop corrections
- F02D41/1401—Introducing closed-loop corrections characterised by the control or regulation method
- F02D2041/1409—Introducing closed-loop corrections characterised by the control or regulation method using at least a proportional, integral or derivative controller
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- F02D41/14—Introducing closed-loop corrections
- F02D41/1401—Introducing closed-loop corrections characterised by the control or regulation method
- F02D2041/1413—Controller structures or design
- F02D2041/1415—Controller structures or design using a state feedback or a state space representation
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- F02D41/00—Electrical control of supply of combustible mixture or its constituents
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- F02D41/14—Introducing closed-loop corrections
- F02D41/1401—Introducing closed-loop corrections characterised by the control or regulation method
- F02D2041/1413—Controller structures or design
- F02D2041/1415—Controller structures or design using a state feedback or a state space representation
- F02D2041/1416—Observer
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- F02D41/1401—Introducing closed-loop corrections characterised by the control or regulation method
- F02D2041/1413—Controller structures or design
- F02D2041/1418—Several control loops, either as alternatives or simultaneous
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- F02D41/00—Electrical control of supply of combustible mixture or its constituents
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- F02D41/14—Introducing closed-loop corrections
- F02D41/1401—Introducing closed-loop corrections characterised by the control or regulation method
- F02D2041/1413—Controller structures or design
- F02D2041/142—Controller structures or design using different types of control law in combination, e.g. adaptive combined with PID and sliding mode
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- F02D41/1401—Introducing closed-loop corrections characterised by the control or regulation method
- F02D2041/1413—Controller structures or design
- F02D2041/1431—Controller structures or design the system including an input-output delay
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/02—Circuit arrangements for generating control signals
- F02D41/14—Introducing closed-loop corrections
- F02D41/1401—Introducing closed-loop corrections characterised by the control or regulation method
- F02D2041/1413—Controller structures or design
- F02D2041/1432—Controller structures or design the system including a filter, e.g. a low pass or high pass filter
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- F02D41/1401—Introducing closed-loop corrections characterised by the control or regulation method
- F02D2041/1433—Introducing closed-loop corrections characterised by the control or regulation method using a model or simulation of the system
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- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/02—Circuit arrangements for generating control signals
- F02D41/14—Introducing closed-loop corrections
- F02D41/1401—Introducing closed-loop corrections characterised by the control or regulation method
- F02D41/1402—Adaptive control
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02D—CONTROLLING COMBUSTION ENGINES
- F02D41/00—Electrical control of supply of combustible mixture or its constituents
- F02D41/02—Circuit arrangements for generating control signals
- F02D41/14—Introducing closed-loop corrections
- 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
- F02D41/1454—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 an oxygen content or concentration or the air-fuel ratio
- F02D41/1456—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 an oxygen content or concentration or the air-fuel ratio with sensor output signal being linear or quasi-linear with the concentration of oxygen
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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 an air-fuel ratio control device for an internal combustion engine, and more particularly, to an air-fuel ratio control device capable of evaluating a deterioration state of a catalyst device for purifying exhaust gas.
- the time from when the output of the oxygen concentration sensor on the upstream side is inverted to when the output of the oxygen concentration sensor on the downstream side is inverted, and the inversion cycle of the oxygen concentration sensor on the downstream side are measured.
- the deterioration state of the catalyst device is evaluated based on the measured values.
- the air-fuel ratio is feedback-controlled in response to the reversal of the output of the oxygen concentration sensor so that the air-fuel ratio of the internal combustion engine is maintained near the stoichiometric air-fuel ratio.
- the air-fuel ratio of the internal combustion engine is maintained near the stoichiometric air-fuel ratio.
- the air-fuel ratio is positively increased from the lean side to the rich side or from the rich side to the lean side in order to evaluate the deterioration state of the catalyst device. I have to change. For this reason, it is not possible to evaluate the deterioration state of the catalyst device when the air-fuel ratio of the internal combustion engine is feedback-controlled so as to ensure the appropriate purification performance of the catalyst device. Therefore, at the time of the evaluation, there was an inconvenience that it was difficult to ensure proper purification performance of the catalyst device.
- the applicant of the present application provided an exhaust gas sensor for detecting the concentration of a specific component in the exhaust gas, for example, the oxygen concentration, on the downstream side of the catalyst device, and the internal combustion engine was designed to converge the output of the exhaust gas sensor to a predetermined target value.
- Techniques for ensuring the optimum purification performance of the catalyst device by manipulating the air-fuel ratio of the mixture to be combusted in the engine have been previously proposed (for example, Japanese Patent Application Laid-Open Nos. 9-13246881, 1 1-1503 51 or U.S. Patent No. 5,852,930, U.S. Patent Application 09 / 15,330, etc.).
- the air-fuel ratio of exhaust gas entering the catalyst device using sliding mode control is set so that the output of the exhaust gas sensor (detected value of oxygen concentration) converges to a predetermined target value (constant value). Calculates the target value (target air-fuel ratio) of the air-fuel ratio obtained from the oxygen concentration of the exhaust gas.
- the optimal air condition of the catalyst Therefore, it is desirable to be able to evaluate the state of deterioration of the catalytic converter while controlling the air-fuel ratio.
- the present invention provides an air-fuel ratio control device for an internal combustion engine that can appropriately evaluate a deterioration state of the catalyst device while securing required purification performance of the catalyst device provided in an exhaust passage of the internal combustion engine.
- the purpose is to provide. Disclosure of the invention
- An air-fuel ratio control device for an internal combustion engine in order to achieve the above object, comprises: a concentration of a specific component in exhaust gas of the internal combustion engine passing through the catalyst device downstream of the catalyst device provided in an exhaust passage of the internal combustion engine. And an air-fuel ratio operation for sequentially generating an operation amount defining an air-fuel ratio of exhaust gas entering the catalyst device so as to converge an output of the exhaust gas sensor to a predetermined target value.
- An air-fuel ratio control device for controlling an air-fuel ratio of an air-fuel mixture to be burned in the internal combustion engine according to the operation amount.
- a value of a predetermined linear function for deterioration evaluation which represents the time-series data as a variable component, is sequentially obtained from the time-series data of the output of the exhaust gas sensor, and the obtained deterioration evaluation is performed.
- a deterioration state evaluation means for evaluating the deterioration state of the catalyst device based on the value of the linear function.
- an operation amount for example, an air-fuel ratio that regulates the air-fuel ratio of exhaust gas entering the catalytic device so that the output of the exhaust gas sensor downstream of the catalytic device converges to a predetermined target value
- a state in which the air-fuel ratio of the air-fuel mixture is operated in accordance with the manipulated variable that is, a state in which convergence control of the output of the exhaust gas sensor to the target value is performed.
- a time-series data of the output of the exhaust gas sensor wherein the time-series data is used as a variable component;
- the value of the linear function is calculated, the value of the linear function is a characteristic correlation with the progress of the deterioration of the catalytic device. Tend to exhibit sex.
- the value of the linear function tends to accumulate near a certain predetermined value. Then, as the deterioration of the catalyst device progresses, the value of the linear function tends to easily take a value apart from the predetermined value. That is, the degree of variation in the value of the linear function increases with the progress of deterioration of the catalyst device.
- the deterioration state evaluation means sets the above-mentioned linear function as a deterioration evaluation linear function, and sequentially obtains the value of the deterioration evaluation linear function from the time-series data of the output of the exhaust gas sensor. Then, the deterioration state of the catalyst device is evaluated based on the value of the linear function for deterioration evaluation.
- the value of the linear function for deterioration evaluation which serves as a basis for evaluating the deterioration state of the catalyst device, is determined based on the air-fuel ratio manipulated variable generated so as to converge the output of the exhaust gas sensor to a predetermined target value.
- the air-fuel ratio operating means is operating the air-fuel ratio of the air-fuel mixture in accordance with the operation amount generated by the means
- the air-fuel ratio is obtained from the time series data of the output of the exhaust gas sensor. That is, the value of the linear function for deterioration evaluation is obtained in a state where the air-fuel ratio is controlled so as to ensure the required purification performance of the catalyst device.
- the deterioration state of the catalyst device can be evaluated while securing the required purification performance of the catalyst device.
- the tendency of the value of the linear function for deterioration evaluation according to the degree of progress of the deterioration of the catalyst device as described above is, according to the knowledge of the present inventors, that the operation by the air-fuel ratio manipulated variable generating means is performed.
- the amount is generated using, for example, sliding mode control, which is a method of feedback control.
- the air-fuel ratio manipulated variable generating means is a means for generating the manipulated variable by using the sliding mode control as described above, particularly, the deterioration is highly correlated with the deterioration state of the catalyst device.
- the evaluation linear function is closely related to the switching function used for the sliding mode control. Therefore, it is preferable that a linear function determined according to the switching function be a linear function for deterioration evaluation.
- the sliding mode control used by the air-fuel ratio manipulated variable generating means includes, for example, a linear function expressing a time series data of a deviation between the output of the exhaust gas sensor and the target value as a variable component.
- the switching function is used as the switching function.
- the deterioration evaluation linear function may be a linear function in which the coefficient value related to the variable component is the same as the coefficient value related to the variable component of the switching function.
- it is a function.
- the linear function may be the switching function itself for controlling the sliding mode.
- the linear function determined according to the switching function for sliding mode control as the linear function for deterioration evaluation, the correlation between the value of the linear function for deterioration evaluation and the deterioration state of the catalyst device is remarkable.
- the deterioration state of the catalyst device can be properly evaluated based on the value of the linear function for deterioration evaluation.
- the deterioration state evaluation means may include a value of the linear function for deterioration evaluation.
- the data representing the degree of variation of the time series data is used as a parameter for deterioration evaluation.
- the parameter for deterioration evaluation is obtained from the time series data of the value of the linear function for deterioration evaluation, and the obtained parameter for deterioration evaluation is obtained. It is preferable to evaluate the state of deterioration of the catalyst device based on the value of overnight.
- the data representing the degree of variation is regarded as a parameter for deterioration evaluation, and this is obtained from the time-series data of the value of the linear function for deterioration evaluation.
- the value of the parameter for deterioration evaluation has a clear correlation with the deterioration state of the catalyst device, and the catalyst value is determined based on the value of the parameter for deterioration evaluation. It is possible to more appropriately evaluate the degradation state of the device.
- the parameter for deterioration evaluation may be, for example, a square value of a deviation between the value of the linear function for deterioration evaluation and a predetermined value ⁇ the absolute value of the deviation, or the like.
- the means may include a low-pass characteristic of a square value or an absolute value of a deviation between each data value of the time series data of the value of the deterioration evaluation linear function and a predetermined value as a center value of the value of the deterioration evaluation linear function.
- the value of the parameter for deterioration evaluation is used for the deterioration evaluation. This is an appropriate value that indicates the degree of variation in the value of the linear function. Then, the value of the parameter for the deterioration evaluation monotonously increases with the progress of the deterioration of the catalyst device, and the correlation with the deterioration state of the catalyst device becomes clear. Therefore, this degradation evaluation parameter Based on the values of the night, it is possible to reliably and reliably evaluate the deterioration state of the catalyst device. '
- the filtering process of the mouth-to-pass characteristics is a filtering process using a sequential statistical processing algorithm.
- the parameter for deterioration evaluation is obtained, thereby eliminating the need for a memory for storing a large number of data of the deviation, its square value, the absolute value, and the like.
- the parameter for deterioration evaluation can be obtained with a small memory capacity.
- an algorithm such as a least squares method, a weighted least squares method, a gradually decreasing gain method, and a fixed gain method is preferable.
- the deterioration evaluation parameter monotonically increases as the deterioration of the catalyst device progresses.
- the deterioration state evaluation means compares the value of the parameter for deterioration evaluation with a predetermined threshold value, thereby deteriorating the deterioration state of the catalyst device to a degree of deterioration corresponding to the threshold value or more. Can be determined.
- the deterioration state evaluation means includes means for determining whether to evaluate the deterioration state of the catalyst device according to a change state of the flow rate of the exhaust gas entering the catalyst device.
- the sliding is performed because the disturbance is small.
- the feedback control such as the mode control
- the output of the exhaust gas sensor is constantly and stably maintained at the target value. Therefore, in such a situation, the value of the linear function for deterioration evaluation tends to accumulate around a predetermined value even when the catalyst device is in a state of advanced deterioration, and when the catalyst device is almost new. It is difficult to distinguish between
- the deterioration state evaluation means does not evaluate the deterioration state of the catalyst device when the flow rate of the exhaust gas entering the catalyst device is maintained at a substantially constant value, and the flow rate of the exhaust gas is substantially constant. The state of deterioration of the catalyst device is evaluated without being maintained.
- the deterioration state evaluation means may be configured to perform the above-described operation when the flow rate of the exhaust gas entering the catalyst device is maintained at a substantially constant value.
- the parameters for deterioration evaluation are not calculated, and the parameters for deterioration evaluation are calculated in a state where the flow rate of the exhaust gas is not maintained substantially constant.
- the air-fuel ratio manipulated variable generation means sequentially obtains data representing an estimated value of the output of the exhaust gas sensor after a dead time of a system from the upstream side of the catalyst device to the exhaust gas sensor.
- An estimator is provided, and the manipulated variable is generated using the data obtained by the estimator.
- the air-fuel ratio manipulated variable generating means may be arranged from an upstream side of the catalyst device.
- the operation amount is generated using the data obtained by the estimation means, that is, a system from the upstream side of the catalyst device to the exhaust gas sensor (this system is defined by the operation amount.
- This system generates the output of the exhaust gas sensor from the air-fuel ratio of the exhaust gas.
- the target exhaust system hereafter generally has a relatively long dead time due to the catalyst device included in the target exhaust system. .
- a system including the air-fuel ratio operating means and the internal combustion engine (this system is a system that generates an air-fuel ratio of exhaust gas entering the catalyst device from the operation amount).
- the air-fuel ratio control system also has a relatively long dead time. These dead times may have an adverse effect on converging the output of the exhaust gas sensor to a target value, and therefore it is desirable to compensate for the effect.
- a total time which is a sum of the dead time and the dead time of the air-fuel ratio operation system, representing the estimated value of the output of the exhaust gas sensor after the dead time of the target exhaust system, or Data representing an estimated value of the output of the exhaust gas sensor after time is obtained by the estimating means, and the manipulated variable is generated using the data.
- the air-fuel ratio manipulated variable generation means outputs the estimated value of the output of the exhaust gas sensor represented by the data obtained by the estimation means in a sliding mode. Control by the eye The manipulated variable is generated so as to converge to the standard value. This makes it possible to appropriately compensate for the effects of the waste time described above. For this reason, the stability of the convergence control of the output of the exhaust gas sensor to the target value can be enhanced, and the required purification performance of the catalyst device can be stably ensured.
- the data representing the estimated value of the output of the exhaust gas sensor is, for example, the output of the exhaust gas sensor and the operation amount generated by the air-fuel ratio operation amount generation means in the past or in accordance with the operation amount. It can be generated using the detected value of the air-fuel ratio of the exhaust gas on the upstream side of the catalyst device.
- the sliding mode control is preferably an adaptive sliding mode control.
- adaptive sliding mode control is a so-called adaptive law, compared to normal sliding mode control, in order to minimize the effects of disturbances and the like.
- Adaptive algorithm By generating the manipulated variable using such an adaptive sliding mode control, the reliability of the manipulated variable is enhanced, and the control of the convergence of the output of the exhaust gas sensor to the target value is performed with high responsiveness and satisfactorily. Can be. In addition, the influence of factors such as mere disturbance other than the deterioration state of the catalyst device on the value of the linear function for deterioration evaluation determined according to the switching function for the sliding mode control is suppressed. The reliability of the evaluation of the deterioration state of the catalyst device based on the parameter for deterioration evaluation indicating the degree of variation of the value of the linear function can be improved.
- the manipulated variable generated by the air-fuel ratio manipulated variable generation means is a target air-fuel ratio of exhaust gas entering the catalyst device, and an air-fuel ratio detecting an air-fuel ratio of exhaust gas entering the catalyst device.
- An air-fuel ratio operating means is provided upstream of the catalyst device, and the air-fuel ratio operating means performs air-fuel ratio control of the air-fuel mixture by feedback control so that the output of the air-fuel ratio sensor converges to the target air-fuel ratio. Manipulate the ratio.
- the output of the air-fuel ratio sensor (the detected value of the air-fuel ratio) for detecting the air-fuel ratio of the exhaust gas entering the catalyst device is set to the target air-fuel ratio by using the manipulated variable as the target air-fuel ratio of the exhaust gas entering the catalyst device.
- the operation amount may be, for example, a correction amount of a fuel supply amount of the internal combustion engine in addition to the target air-fuel ratio. Further, the operation of the air-fuel ratio of the air-fuel mixture according to the operation amount may be performed by feedforward control based on the operation amount. Further, in the present invention, in order to evaluate the deterioration state of the catalyst device while securing the optimum purification performance of the catalyst device, an oxygen concentration sensor (o 2 sensor) is used as the exhaust gas sensor, and the target value is set to a predetermined value. It is preferable to set a constant value of
- FIG. 1 is a block diagram showing an overall system configuration of a first embodiment of the air-fuel ratio control apparatus of the present invention
- FIG. 2 is an output characteristic diagram of the 0 2 sensor and the air-fuel ratio sensor used in the apparatus of FIG. 1
- FIG. 3 is a block diagram showing a basic configuration of a main part of the apparatus of FIG. 1
- FIG. 4 is an explanatory view for explaining a sliding mode control used in the apparatus of FIG. 1
- FIGS. 5 to 8 are apparatuses of FIG.
- FIG. 9 is a block diagram for explaining a method of evaluating the deterioration state of the catalyst device used in FIG. 9, and
- FIG. 9 is a block diagram for explaining an adaptive controller used in the device of FIG. FIG.
- FIG. 10 is a flowchart showing the processing of the agency-side control unit of the apparatus of FIG. 1
- FIG. 11 is a flowchart showing the subroutine processing of the flowchart of FIG.
- FIG. 12 is a flowchart showing the processing of the exhaust-side control unit of the apparatus of FIG. 1
- FIGS. 13 to 16 are flowcharts showing the subroutine processing of the flowchart of FIG.
- FIGS. 17 to 19 are flowcharts showing the subroutine processing of the flowchart of FIG.
- FIG. 20 is a block diagram showing a main part configuration (exhaust-side control unit) of an air-fuel ratio control device for an internal combustion engine according to a second embodiment of the present invention
- FIG. 21 is a device of the exhaust-side control unit shown in FIG.
- FIG. 22 is a diagram for explaining the processing of the main part of the flowchart of FIG. 21.
- FIG. 1 is a block diagram showing the overall system configuration of the device of the present embodiment.
- 1 is, for example, a four-cylinder engine (internal combustion engine) mounted as a propulsion source of a vehicle or an eight-brid vehicle.
- Exhaust gas generated by combustion of a mixture of fuel and air for each cylinder of the engine 1 is collected in a common exhaust pipe 2 (exhaust passage) in the vicinity of the engine 1, and is discharged into the atmosphere through the exhaust pipe 2. Will be released.
- the exhaust pipe 2 is provided with two catalytic devices 3 and 4 composed of, for example, a three-way catalyst in order from the upstream side in order to purify the exhaust gas.
- the catalyst device for evaluating the deterioration state is the upstream catalyst device 3, and the downstream catalyst device 4 may be omitted.
- the air-fuel ratio of the exhaust gas entering the catalyst device 3 (specifically, the oxygen concentration in the exhaust gas entering the catalyst device 3) so as to secure the optimal deterioration performance of the catalyst device 3
- the air-fuel ratio ascertained from the following is sometimes referred to simply as the air-fuel ratio of engine 1.
- the deterioration state of the catalyst device 3 is evaluated while performing the air-fuel ratio control.
- an exhaust pipe 2 is provided upstream of the catalyst device 3 (more specifically, at a point where exhaust gas is collected for each cylinder of the engine 1).
- air-fuel ratio sensor 5 that, with 0 2 sensor (oxygen concentration sensor) 6 as the exhaust gas sensor provided in the exhaust pipe 2 downstream of the catalytic converter 3 (upstream of the catalytic converter 4), the sensors 5
- a control unit ⁇ ⁇ for performing a control process described later and evaluating the deterioration state of the catalyst device 3 based on the outputs of the above-mentioned items.
- control unit 7 along with the output of the air-fuel ratio sensor 5 and 0 2 sensor 6, the rotational speed sensor Saya intake pressure sensor (not shown) for detecting the operating condition of the engine 1, a coolant temperature sensor, etc.
- the outputs of various sensors are provided.
- 0 2 sensor 6 is usually specific Rei_2 sensor for generating (output indicating the detection value of the oxygen concentration) output V02 / OUT having a level depending on the oxygen concentration in the exhaust gas which has passed through the catalytic converter 3.
- the oxygen concentration in the exhaust gas depends on the air-fuel ratio of the air-fuel mixture generated by burning the exhaust gas.
- the output V02 / OUT of this 0 2 sensor 6, as shown in FIG. 2 by the solid line a in the state as an air-fuel ratio corresponding to the oxygen concentration in the exhaust gas exists in the range of near stoichiometric air-fuel ratio ⁇ , the This results in a highly sensitive change that is almost proportional to the oxygen concentration in the exhaust gas.
- the output V02 / OUT of the O 2 sensor 6 is saturated, ing a substantially constant level.
- the air-fuel ratio sensor 5 generates an output KACT indicating the detected value of the air-fuel ratio of the engine 1 which is detected by the oxygen concentration of the exhaust gas entering the catalyst device 3.
- the air-fuel ratio sensor 5 is constituted by, for example, a wide-range air-fuel ratio sensor described in detail by the present applicant in Japanese Patent Application Laid-Open No. 4-369471 or U.S. Pat. No. 5,391,282. It is a thing. Then, the air-fuel ratio sensor 5, as shown by the solid line b in FIG. 2, to produce the output of level proportional thereto over a wide range of oxygen concentration in the exhaust gas than 0 2 sensor 6.
- the air-fuel ratio sensor 5 (hereinafter referred to as the LAF sensor 5) It produces a proportional output KACT over a wide range of air-fuel ratios corresponding to the oxygen concentration in the gas.
- the control unit 7 performs a process for calculating a target air-fuel ratio KCMD (a target value of the air-fuel ratio of the engine 1) as an operation amount defining the air-fuel ratio of the engine 1, and evaluates a deterioration state of the catalyst device 3.
- the control unit 7a (hereinafter referred to as the “exhaust-side control unit 7a”), which performs the processing for performing the control, and the fuel injection amount (fuel supply amount) of the engine 1 are adjusted according to the target air-fuel ratio KCMD.
- a control unit 7b hereinafter, referred to as an engine-side control unit 7b) as an air-fuel ratio operating means for controlling the air-fuel ratio of the air-fuel mixture to be burned in the engine 1.
- control units 7a and 7b are configured using a microcomputer, and execute respective processes in a predetermined control cycle.
- the exhaust-side control unit is used.
- the control cycle in which the process 7a executes the process takes into account the dead time and calculation load, etc., which will be described later, caused by the catalyst device 3. Therefore, it is set to a predetermined period (for example, 30 to 100 ms).
- the processing executed by the engine-side control unit 7b (the adjustment processing of the fuel injection amount) needs to be performed in synchronization with the rotation speed of the engine 1 (specifically, the combustion cycle of the engine 1). For this reason, the control cycle in which the engine-side control unit 7b executes the processing is a cycle synchronized with the crank angle cycle of the engine 1 (so-called TDC).
- the fixed cycle of the control cycle of the exhaust-side control unit 7a is longer than the crank angle cycle (TDC).
- the engine-side control unit 7b has a basic structure that A basic fuel injection quantity calculator 8 for determining a fuel injection quantity T im, the first correction coefficient calculator 9 and the obtaining a first correction coefficient KTOTAL and the second correction coefficient KCMDM to correct the basic fuel injection quantity T im, respectively 2 a correction coefficient calculating unit 10.
- the basic fuel injection amount calculation unit 8 calculates a predetermined fuel injection amount (fuel supply amount) of the engine 1 based on the rotation speed NE and the intake pressure PB of the engine 1 based on the map.
- the basic fuel injection amount T im is calculated by correcting the reference fuel injection amount according to the effective opening area of the throttle valve (not shown) of the engine 1.
- the first correction coefficient KTOTAL obtained by the first correction coefficient calculation unit 9 is based on the exhaust gas recirculation rate of the engine 1 (the ratio of exhaust gas contained in the intake air of the engine 1), and the engine 1 This is for correcting the basic fuel injection amount T im in consideration of a purge amount of fuel supplied to the engine 1 at the time of purging, a cooling water temperature of the engine 1, an intake air temperature, and the like.
- the second correction coefficient KCMDM obtained by the second correction coefficient calculation unit 10 is a cooling effect of the fuel flowing into the engine 1 in accordance with the target air-fuel ratio KCMD calculated by the exhaust-side control unit 7a as described later. This is for correcting the basic fuel injection amount T im in consideration of the charging efficiency of the intake air by the intake air.
- the correction of the basic fuel injection amount T im by the first correction coefficient KTOTAL and the second correction coefficient KCMDM is performed by multiplying the basic fuel injection amount T im by the first correction coefficient KTOTAL and the second correction coefficient KCMDM.
- the required fuel injection amount T cyl of the engine 1 is obtained.
- the engine-side control unit 7b further outputs the LAF sensor 5 output KACT (the detected value of the air-fuel ratio of the engine 1) to the target air-fuel ratio KCMD calculated by the exhaust-side control unit 7a.
- the feedback control unit 14 controls the air-fuel ratio of the air-fuel mixture to be burned in the engine 1 by adjusting the fuel injection amount of the engine 1 by feedback control so as to converge.
- the feedback control unit 14 includes a global feedback control unit 15 that performs feedback control of the overall air-fuel ratio of each cylinder of the engine 1, and a feedback control unit 15 that determines the air-fuel ratio of each cylinder of the engine 1. This is separated from the local feedback control unit 16 that performs feedback control.
- the global feedback control unit 15 corrects the required fuel injection amount T cyl so that the output KACT of the LAF sensor 5 converges to the target air-fuel ratio KCMD (multiply the required fuel injection amount T cyl by )
- the feedback correction coefficient KFB is calculated sequentially.
- the global feedback control unit 15 uses a well-known PID control according to a deviation between the output KACT of the LAF sensor 5 and the target air-fuel ratio KCMD, and performs a feedback operation amount as the feedback correction coefficient KFB.
- An adaptive controller 18 (referred to as STR in the figure) that adaptively obtains the operation amount KSTR is independently provided.
- the feedback operation amount KLAF generated by the PID controller 1 # is a state in which the output KACT (detected value of the air-fuel ratio) of the LAF sensor 5 matches the target air-fuel ratio KCMD.
- the operation amount KLAF can be used as it is as the feedback correction coefficient KFB. It has become so.
- the feedback manipulated variable KSTR generated by the adaptive controller 18 becomes the “target air-fuel ratio KCMD” when the output KACT of the LAF sensor 5 matches the target air-fuel ratio KCMD.
- the global feedback control unit 15 divides the feedback operation amount KLAF generated by the PID controller 17 and the feedback operation amount KSTR generated by the adaptive controller 18 by the target air-fuel ratio KCMD.
- the feedback operation amount kstr is alternately and appropriately selected by the switching unit 20. Then, either one of the feedback operation amounts KLAF or kstr is used as the feedback correction coefficient KFB, and the correction coefficient KFB is multiplied by the required fuel injection amount T cyl to obtain the required fuel injection amount. Correct the quantity T cyl.
- the global feedback controller 15 (particularly, the adaptive controller 18) will be described later in more detail.
- the observer 21 estimates the actual air-fuel ratio # nA / F for each cylinder as follows.
- the system from engine 1 to LAF sensor 5 (collection of exhaust gas for each cylinder) is calculated based on the actual air-fuel ratio # nA / F for each cylinder of engine 1 and the air-fuel ratio detected by LAF sensor 5.
- LAF Modeling is performed in consideration of the detection response delay of the sensor 5 (for example, first-order delay) and the time contribution of the air-fuel ratio of each cylinder of the engine 1 to the air-fuel ratio detected by the LAF sensor 5.
- the actual air-fuel ratio # nA / F of each cylinder is estimated from the output KACT of the LAF sensor 5 in reverse.
- each PID controller 22 of the local feedback control unit 16 converts the output KACT of the LAF sensor 5 to all cylinders of the feedback correction coefficient #nKLAF obtained by each PID controller 22 in the previous control cycle.
- the value obtained by dividing by the average value of is used as the target value of the air-fuel ratio of each cylinder.
- the feedback correction coefficient for each cylinder in this control cycle is set so that the deviation between the target value and the estimated value of the actual air-fuel ratio # nA / F for each cylinder obtained by the observer 21 is eliminated. Find nKLAF.
- the local feedback control unit 16 multiplies the required fuel injection amount T cyl by the feedback correction coefficient KFB of the global feedback control unit 15 to a feedback correction coefficient for each cylinder.
- the output fuel injection amount #n T out of each cylinder obtained in this way is taken into account by the adhesion correction unit 23 for each cylinder provided in the engine-side control unit 7b, taking into account the adhesion of the fuel wall to the intake pipe. After the correction is made for each cylinder, the correction is given to a fuel injection device (not shown) of the engine 1. Then, fuel is injected into each cylinder of the engine 1 in accordance with the output fuel injection amount #n T out that has undergone the adhesion correction.
- the sensor output selection processing unit denoted by reference numeral 24 outputs the output KACT of the LAF sensor 5 suitable for estimating the actual air-fuel ratio # nA / F of each cylinder by the observer 21.
- the selection is made in accordance with the operation state of item 1, which is disclosed in detail by the applicant of the present invention in Japanese Patent Application Laid-Open No. Hei 7-259589 or US Pat. No. 5,540,209. Therefore, further description is omitted here.
- 0 at 2 is an output V02 / OUT of the sensor 6 a predetermined constant value V02 / TARGET air-fuel ratio of the state of the engine 1 so as to settle in (see FIG. 2), the catalytic converter 3 is in the deterioration state or the like Demonstrate the optimal purification performance without depending on it. Therefore, in the present embodiment, the constant value V02 / TARGET is set as the target value V02 / TARGET of the output V02 / OUT of the O 2 sensor 6.
- the reference value FLAF / BASE for the output KACT of the LAF sensor 5 is set to “stoichiometric air-fuel ratio”.
- the subtraction processing unit 1 1, 1 2 the differential output V02 of the differential output kact and 0 2 sensor 6, respectively LAF sensor 5 deviation kact, V02 which Ru respectively determined.
- the exhaust-side control unit 7a further includes an exhaust-side main processing unit 13 in which the data of the deviation output kact and V02 are given as the data of the output of the LAF sensor 5 and the data of the output of the ⁇ 2 sensor 6, respectively. It has.
- the exhaust-side main arithmetic processing section 13 has a function as an air-fuel ratio manipulated variable determining means for sequentially calculating a target air-fuel ratio KCMD of the engine 1 based on the data of the deviation output kact, V02. with the and the target air-fuel ratio calculating means 1 3 a, the deteriorated state evaluating means 1 3 b of evaluating the deteriorated state of the catalytic converter 3 based on the data of the differential output V02 of ⁇ 2 sensor 6.
- the catalyst unit 3 including an exhaust system of over the point locations from ⁇ 2 sensor 6 of the LAF sensor 5 in the exhaust pipe 2 (refer to FIG. 1 reference numeral E ) Is the control target.
- the sliding mode control for details, see FIG.
- the deteriorated state evaluating means 1 3 b is adapted to evaluate the deteriorated state of the catalytic converter 3 based on 0 2 value of the deterioration evaluating linear function described later determined from the time series de Isseki the differential output VO2 of the sensor 6,
- the operation of the deterioration alarm 29 provided in the apparatus of the present embodiment is controlled according to the evaluation result.
- the deterioration alarm 29 notifies the deterioration state of the catalyst device 3 to the outside by turning on or blinking a lamp, sounding a buzzer, or displaying characters or graphics.
- the target air-fuel ratio calculation means 13a and the deterioration state evaluation means 13b will be further described.
- the target exhaust system E in order to perform the processing of the means 13a, the target exhaust system E is connected to the output KACT of the LAF sensor 5 (the air-fuel ratio of the engine 1). From the detected value) Regarded as a system for generating an answer delay elements through by ⁇ output of 2 sensor 6 V02 / QUT (detection value of the oxygen concentration in the exhaust gas which has passed through the catalytic converter 3), is modeled by its behavior in advance discrete-time system .
- a system including the engine 1 and the engine-side control unit 7b is used as a system for generating the output KACT of the LAF sensor 5 from the target air-fuel ratio KCMD via a dead time element (hereinafter, this system is referred to as an air-fuel ratio operation system).
- the behavior is modeled in advance in a discrete-time system.
- V02 ⁇ k + l) ai 'V02 (k) + a2' V02 ⁇ k —! + Bi ⁇ kact (k—di) (1)
- the equation (1) is regarded as the object exhaust system E is a system that generates a differential output V02 of the O 2 sensor 6 via the differential output kact or al, dead time element and a response delay element of the LAF sensor 5,
- the behavior of the target exhaust system E is represented by a discrete time model (more specifically, an autoregressive model having a dead time in the deviation output kact as an input amount of the target exhaust system E).
- “k” indicates the number of discrete-time control cycles of the exhaust-side control unit 7 a (hereinafter the same), and “dl” indicates the target exhaust system E.
- those dead time (details of dead time required for until the air-fuel ratio of each time point detected by the LAF sensor 5 is reflected in the output V02 / OUT of ⁇ 2 sensor 6) expressed with the number of control cycles that exist It is.
- the value of the dead time dl in the exhaust system model represented by the equation (1) is set in advance to be equal to the actual dead time of the target exhaust system E or to be slightly longer.
- the first and second terms on the right side of equation (1) correspond to the response delay element of the target exhaust system E, respectively.
- the first term is the first-order autoregressive term
- the second term is the second-order. This is the autoregressive term of the eye.
- Al and “a2” are the gain coefficient of the first-order autoregressive term and the gain coefficient of the second-order autoregressive term, respectively. If these gain coefficients al, a2 is put it another way, a 0 2 coefficients relative to the differential output VO2 of the sensor 6 as an output quantity of the object exhaust system E.
- These gain coefficients al, a2, and bl are parameters that define the behavior of the exhaust system model. In the present embodiment, they are sequentially identified by an identifier described later.
- the model of the discrete-time system of the air-fuel ratio operation system (hereinafter referred to as the air-fuel ratio operation system model) including the engine 1 and the engine-side control unit ⁇ b is the same as the exhaust system model in this embodiment.
- this is called the target deviation air-fuel ratio kcmd
- the target deviation air-fuel ratio kcmd the following equation is used.
- This equation (2) is a system in which the air-fuel ratio operation system generates the deviation output kact of the LAF sensor 5 from the target deviation air-fuel ratio kcmd via the dead time element (the deviation output kact in each control cycle is the target output before the dead time.
- the system is considered to be a system that matches the deviation air-fuel ratio kcmd), and the air-fuel ratio operation system is represented by a discrete-time model.
- d2 is the dead time of the air-fuel ratio operation system (specifically, the dead time required until the target air-fuel ratio KCMD at each point is reflected on the output KACT of the LAF sensor 5). ) Is the number of control cycles of the exhaust-side control unit 7a.
- the dead time of the air-fuel ratio operation system varies depending on the engine speed NE of the engine 1, and becomes longer as the engine 1 speed decreases.
- the value of the dead time d2 in the air-fuel ratio operating system model represented by the equation (2) is considered in consideration of the above-described characteristics of the dead time of the air-fuel ratio operating system.
- the idle time that the actual air-fuel ratio operating system has at the idling speed which is the rotation speed in the rotation range (this is the maximum dead time that the air-fuel ratio operating system can take at any given engine 1 speed).
- the air-fuel ratio operation system actually includes a response delay element caused by the engine 1 in addition to a dead time element.
- the response delay of the output KACT of the LAF sensor 5 with respect to the target air-fuel ratio KCMD is basically compensated by the feedback control unit 14 (particularly the adaptive controller 18) of the engine-side control unit 7b.
- the target air-fuel ratio calculating means 13a of the exhaust-side main arithmetic processing unit 13 calculates the target air-fuel ratio KCMD based on the exhaust system model and the air-fuel ratio operation system model expressed by the equations (1) and (2), respectively. The calculation process is performed in the control cycle (constant control cycle) of the exhaust-side control unit 7a. In order to perform this processing, a functional configuration as shown in FIG. 3 is provided.
- the target air-fuel ratio calculation means 13a calculates the identification values al, a, and a2 of the gain coefficients al, a2, and bl, which are parameters to be set in the exhaust system model (Equation (1)).
- No., No., bl No., and No. (hereinafter referred to as identification gain coefficients al, a2, and bl) are identified for each control cycle.
- estimated differential output V02 bar For each control cycle, and a sliding mode controller 27 for sequentially calculating the target air-fuel ratio KCMD for each control cycle by the processing of the adaptive sliding mode control.
- the algorithm of the arithmetic processing by the identifier 25, the estimator 26, and the sliding mode controller 27 is constructed as follows.
- the identifier 25 calculates the values of the gain coefficients al, a2, and bl in real time so as to minimize the modeling error of the exhaust system model expressed by the above equation (1) with respect to the actual target exhaust system E. And the identification process is performed as follows.
- the identifier 25 first determines the identification gain coefficients al, a2, and bl of the currently set exhaust system model. That is, the values of the identified gain coefficients al (kl) hat, a2 (kl) hat, bl (kl) hat determined in the previous control cycle, Using the deviation output kact of the LAF sensor 5 and the past value data kact (k-dl-l), V02 (k-1), and V02 (k-2) of the ⁇ 2 sensor 6 deviation output V02 , the following equation (3) by the value V02 (k) hat of the differential output of ⁇ 2 sensor 6 on the exhaust system model V02 (output of the exhaust system model) (hereinafter, referred to as the identified differential output VO2 (k) hearts g) Ask for.
- W2 (k) ai (k ⁇ l), V02 (k-1) -Ha2 ⁇ k-1) 'V02 (k-2) + bi (k-1), kact (k-d -l)
- This equation (3) is obtained by shifting the above equation (1) representing the exhaust system model by one control cycle to the past side, and as identification coefficients al, a2, and bl as identification gain coefficients al (kl), a2 (kl) hat and bl (k-1) hat are used.
- the above equation (3) is expressed by the following equation (6).
- 2 5 further identifier, the formula (3) or formula identified differential output 0 2 sensor 6 that obtained by (6) V02 (k) ha Bok and now differential output current 0 2 sensor 6 V02 (k)
- the deviation id / e (k) is calculated by the following equation (7) as representing the modeling error of the exhaust system model with respect to the actual target exhaust system E (hereinafter, the deviation id / e is referred to as the identification error id / e). .
- the identifier 25 generates a new identification gain coefficient al (k) hat so as to minimize the identification error id / e. , A2 (k) hat, bl (k) hat, in other words, the new vector ⁇ ⁇ ⁇ (k) (hereinafter referred to as the identification gain coefficient vector) ⁇ ) is calculated by the following equation (8). That is, the identifier 25 calculates the identification gain coefficients al (kl), a2 (kl), and bl (kl) determined in the previous control cycle in proportion to the identification error id / e (k). The new identification gain coefficients al (k), a2 (k), and bl (k) are obtained by changing the amount by the set amount.
- ⁇ (k) ⁇ ( ⁇ -1) + ⁇ 0 (k). Id / e (k) (8) where “ ⁇ ⁇ ” in equation (8) is the third order determined by the following equation (9). ⁇ U a iL , P ⁇ (the coefficient coefficient vector that defines the degree of change in accordance with the identification error id / e of each identification gain coefficient al, a2, and b1). k— 1). ⁇ (k) ⁇
- the identifier 25 in the present embodiment basically performs the above-described algorithm (arithmetic processing) to minimize the identification error id / e so as to minimize the identification gain coefficient al hat, a2 of the exhaust system model.
- the knots, bl knots, and knots are sequentially obtained for each control cycle. Through such processing, the identification gain coefficients al hat, a2 no, cut, and bl hat suitable for the actual target exhaust system E are obtained sequentially.
- the algorithm described above is a basic algorithm executed by the identifier 25.
- the estimator 26 calculates the dead time dl of the target exhaust system E and the dead time d2 of the air-fuel ratio operation system in the calculation process of the target air-fuel ratio KCMD by the sliding mode controller 27 described in detail later. in order to compensate for the effects, the total dead time d (two dl + d2) after 0 2 the estimated differential output VO2 bar which is an estimated value of the deviation output VO2 of the sensor 6 which sequentially determines in each control cycle It is.
- the algorithm of the estimation process is constructed as follows.
- equation (11) is obtained by applying equation (2) representing the air-fuel ratio operation model to equation (1) representing the exhaust system model.
- V02 ⁇ K + 1) aiV02 (k) + ai? ⁇ V02 (k-1) 10 btkcmd (k ⁇ -di-d2)
- V02 (k + d) aiV02 (k) + a2 'V02 (k-1) + ⁇ ⁇ kcmd (k-j) (12)
- a l, 2 are the first powers of the power matrix Ad (d: total dead time) of the matrix A defined by the proviso in the formula (I 2).
- V02 (k + d) atV02 (k) + a2 'V02 (k-i)
- the coefficients H1, H2, and H3 required to calculate the estimated deviation output V02 (k + d) bar by the equation (13) are used.
- the estimated deviation output V02 (k + d) bar may be obtained by the calculation of the equation (1 2) without using the data of the deviation output kact of the LAF sensor 5.
- V02 (k + d) ai. V02 (k) + a2.
- the sliding mode controller 27 will be described. .
- Suraidi Ngumo de controller 2 of the present embodiment 7 usually a Suraide I Ngumo to de control, adaptive in consideration of the adaptive law for eliminating the effect of disturbance as possible scan line Di Ngumo de controlled by Ri O 2 sensor output V02 / OUT of 6 so as to settle to the target value VO2 / tARGET (the ⁇ 2 differential output V02 of the sensor 6 to converge to "0"), before Symbol object exhaust system to be controlled
- the target value of the difference between the input amount to be given to E specifically, the output KACT (detected value of the air-fuel ratio) of the LAF sensor 5) and the reference value FLAF / BASE, which is equal to the target deviation air-fuel ratio kcmd.
- This input amount is referred to as SLD operation input Usl
- the target air-fuel ratio KCMD is determined from the determined SLD operation input Usl.
- the algorithm for the processing is constructed as follows.
- the state quantity to be controlled (control quantity) is, for example, each control plane.
- V02 (k) of the 0 2 sensor 6 obtained in the cycle
- V02 (k-1) obtained one control cycle before
- V02 (k-1) as a linear function with variable components.
- the vector X defined by the proviso in the equation (15) as a vector having the deviation outputs V02 (k) and V02 (k-1) as components is hereinafter referred to as a state quantity X.
- o ⁇ k) s ⁇ 'V02 (k) + S2V02 (k-1)
- the coefficients sl and s2 of the switching function ⁇ are set so as to satisfy the condition of the following equation (16).
- the hyperplane is also called a switching line or a switching surface, depending on the order of the phase space.
- the state quantity which is a variable component of the switching function for the sliding mode control is actually obtained before the estimation by the estimator 26.
- the time series data of the estimated deviation output V02 bar is used, which will be described later.
- the equivalent control input Ueq, the reaching law input Urch, and the adaptive law input Uadp are the discrete-time model represented by the above-mentioned equation (11) (the LAF sensor in the equation (1)). 5) is determined as follows based on the deviation output kact (k-dl) of 5) and the target deviation air-fuel ratio kcmd (kd) using the total dead time d).
- the equivalent control input Ueq satisfying such a condition is given by the following equation (18) using the equations (11) and (15).
- This equation (18) is a basic equation for obtaining the equivalent control input Ueq (k) for each control cycle in the present embodiment. It is an expression.
- the reaching law input Urch is basically determined by the following equation (19).
- the coefficient F in the equation (19) (which defines the gain of the reaching law) is set so as to satisfy the condition of the following equation (20).
- the adaptive law input Uadp is basically determined by the following equation (22) ( ⁇ T in equation (22) is the exhaust-side control unit 7a Control cycle).
- the adaptive law input Uadp takes into account the total dead time d, and the value of the switching function ⁇ up to the time after the total waste time d. It is determined to be proportional to the integrated value of the product of the exhaust side control unit 7a and the period ⁇ T for each control cycle (this corresponds to the integrated value of the value of the switching function ⁇ ).
- the sliding mode controller 27 in the present embodiment basically includes an equivalent control input Ueq. Reaching law input Urch and an adaptive law input determined by the above equations (18), (19), and (22). sum of Uadp there so determined as the SLD manipulating input Usl to be applied to (Ueq + Urch + Uadp) of the object exhaust system E, the equation (1 8), for use in (1 9), (2 2) 0 2
- the deviation output V02 (k + d) and V02 (k + dl) of the sensor 6 and the value (k + d) of the switching function are future values. Therefore, it cannot be obtained directly.
- the time series data of the estimated deviation output V02 bar sequentially obtained by the estimator 26 as described above is a state quantity to be controlled, and the equation (15)
- a switching function ⁇ bar for sliding mode control is defined by the following equation (25).
- This switching function ⁇ bar is used when the deviation output V02 in the equation (15) is obtained. This is equivalent to replacing the time series data with the time series data of the estimated deviation output V02 bar).
- ⁇ ( ⁇ ) ⁇ ⁇ V02 (k) + s2 ′ V02 ⁇ k ⁇ 1)
- the sliding mode controller 27 determines the reaching law input Urch by the above equation (19).
- the reaching law input Urch for each control cycle is calculated by the following equation (26) using the value of the switching function bar represented by the above equation (25) instead of the value of the switching function ⁇ .
- Urch (k) ⁇ -F-a (k + d) (26)
- the sliding mode controller 27 uses the switching function for determining the adaptive law input Uadp according to the equation (22).
- the adaptive law input Uadp for each control cycle is calculated by the following equation (27) using the value of the switching function ⁇ bar expressed by the above equation (25) instead of the value of ⁇ .
- Uadp (k) 'G- ⁇ (Hi ( ⁇ T)) (27)
- the equivalent control input Ueq, the reaching rule input Urch, and the adaptive rule input are given by the above equations (24), (26), and (27).
- the gain coefficients al, a2, and bl required for calculating the law input Uadp are basically the latest identification gain coefficients al (k) obtained by the identifier 25. Hats, a2 (k) hats, and bl (k) hats are used.
- the sliding mode controller 27 targets the sum of the equivalent control input Ueq, the reaching law input Urch, and the adaptive law input Uadp obtained by the above equations (24), (26), and (27), respectively. It is obtained as the SLD operation input Usl to be given to the exhaust system E (see the above equation (17)).
- the setting conditions of the coefficients si, s2, F, and G used in the equations (24), (26), and (27) are as described above.
- This is the basic calculation for determining the SLD operation input Usl ( target deviation air-fuel ratio kcmd) to be given to the target exhaust system E by the sliding mode controller 27 in this embodiment for each control cycle. Processing (algorithm).
- the SLD manipulating input Usl is 0 to the estimated differential output V02 bar 2 sensor 6 to the power sale by converging to "0" (result 0 2 Se Is determined so that the output V02 / OUT of the sensor 6 converges to the target value V02 / TARGET).
- the sliding mode controller 27 in the present embodiment finally obtains the target air-fuel ratio KCMD sequentially for each control cycle
- the SLD operation input Usl obtained as described above is determined by the LAF sensor.
- sliding mode controller 27 finally sets the above-mentioned reference value FLAF to SLD operation input Usl obtained as described above for each control cycle as shown in the following equation (28).
- the target air-fuel ratio KCMD is determined.
- KCMD (k) Usi (k) + FLAF / BASE
- the above is the basic algorithm for determining the target air-fuel ratio KCMD by the sliding mode controller 27 in the present embodiment.
- the stability of the processing of the adaptive sliding mode control by the sliding mode controller 27 is determined, and the value of the SLD operation input Usl is limited. Will be described later. Next, the processing of the deterioration state evaluation means 13b will be described.
- FIGS. show the new catalyst unit 3, the catalyst unit 3 with a relatively small degree of degradation, and the catalyst unit 3 with a relatively large degree of degradation, respectively, as described above.
- the fuel injection amount is adjusted according to the target air-fuel ratio KCMD, it is obtained for each control cycle of the exhaust-side control unit 7a.
- Time-series data V02 (k), V02 (k) of the deviation output VO2 of the 2- sensor 6 -1), that is, the sampling data of the state quantity X is indicated by stippling.
- the value of the switching function ⁇ determined by the above equation (15) can easily take a value separated from “0” as the catalyst device 3 deteriorates, and the value of the switching function ⁇ becomes “0”.
- the above tendency is obtained by using the estimated deviation output V02 bar obtained by the estimator 26 as a variable component and the switching function ⁇ bar 1 determined by the above equation (25) (sliding mode control in the present embodiment).
- the switching function ⁇ bar while is to use an estimate of the differential output V02 of ⁇ 2 sensor 6, the actual deviation output V02 of the formula (1 5) switching function of ⁇ 2 sensor 6 Since it is used, it is considered that the actual deterioration state of the catalyst device 3 is better reflected.
- the expression (15) The deterioration state of the catalyst device 3 is evaluated based on the value of the switching function ⁇ .
- the actual switching function for sliding mode control is, as described above, the switching defined by the above equation (25) using the estimated deviation output VO2 bar obtained by the estimator 26 as a variable component. It is a function function.
- the switching function ⁇ defined by the equation (15) is not the rinsing function for controlling the sliding mode in the present embodiment. Therefore, in the following description, the function ⁇ defined by the equation (15) is referred to as a degradation evaluation linear function ⁇ .
- an algorithm for the deterioration state evaluation means 13 to evaluate the deterioration state of the catalyst device 3 based on the linear function ⁇ for deterioration evaluation is constructed as follows.
- the deterioration state evaluation means 13b is configured to calculate the linear function ⁇ of the deterioration evaluation.
- the square value 2 of the value is sequentially obtained for each control cycle.
- the said square value shed 2 of the center value by performing filtering processing of the square values sigma 2 to the low-pass characteristics (hereinafter, reference numeral LSa 2 that is subjected to this) is determined as a deterioration evaluating parameter Isseki a.
- the fill Yuri ing process for obtaining a deterioration evaluating parameter Isseki LS monument 2 is constituted by a sequential statistical processing algorithm is given by the following equation (2 9).
- the deterioration evaluating parameter LSo 2 includes a for each control cycle of the exhaust-side control unit 7 a, the previous value LSa 2 of deterioration evaluating parameter Isseki LS sigma 2 (kl), said square value sequentially from the current value sigma 2 of sigma 2 (k), the following equation (3 0) Gay Nparame Isseki and BP is updated in each control cycle by the recurrence formula It is required while being updated.
- ⁇ k) ⁇ - ⁇ ' ⁇ ⁇ 2 ⁇ ⁇ Ck ⁇ d- Bp — O (30)
- “7? 1” and “7? 2” in equation (30) are 0 ⁇ 771 ⁇ 1 and 0 ⁇ 7? 2 ⁇ 2 are set so as to satisfy the condition.
- various methods such as the fixed gain method, the decreasing gain method, the weighted least squares method, the least squares method, the fixed trace method, etc.
- a specific algorithm is configured. In this embodiment, for example, 7-1 is set to a positive predetermined value smaller than “1” (0 7) 1 ⁇
- FIG. 8 shows the deterioration evaluation parameter LSa 2 and the flow rate of the exhaust gas flowing through the catalyst device 3 (hereinafter referred to as the exhaust gas volume) in each of the deterioration states of the catalyst device 3 in FIGS. ).
- the deterioration evaluation parameter LSa 2 is almost constant regardless of the exhaust gas volume in each deterioration state of the catalyst device 3, and the deterioration of the catalyst device 3 progresses. The value increases accordingly. Therefore, the value of the deterioration evaluation parameter LSo 2 indicates the degree of deterioration of the catalyst device 3.
- the catalyst device 3 when the catalyst device 3 needs to be replaced or the catalyst device 3 is deteriorated to such an extent that the replacement time is near (hereinafter referred to as “deterioration progress state”), the catalyst device 3 is not so deteriorated.
- the state of deterioration of the catalyst device 3 is identified separately from the state (hereinafter referred to as the undegraded state). In the “deterioration progress state”, the fact is notified by the deterioration alarm 29.
- the deterioration evaluation parameter LS a 2 is equal to or greater than the threshold value CATAGELMT, the deterioration state of the catalyst device 3 is determined to be “deterioration progress state”, and the deterioration evaluation parameter LS G 2 is determined. If the above threshold value CATAGELMT is not reached, it is determined that the deteriorated state of the catalyst device 3 is “undegraded state”.
- the algorithm described above is a basic algorithm for evaluating the deterioration state of the catalyst device 3 by the deterioration state evaluation means 13b.
- the deterioration state evaluation means 13b also performs additional processing such as grasping the change state of the exhaust gas volume when evaluating the deterioration state of the catalyst device 3, which will be described later.
- the global feedback control unit 15 performs feedback control so that the output KACT (detected value of the air-fuel ratio) of the LAF sensor 5 converges to the target air-fuel ratio KCMD as described above. It is what you do. At this time, if such feedback control is performed only by well-known PID control, stable controllability is secured against dynamic behavior changes such as changes in the operating state of the engine 1 and changes over time. Is difficult to do.
- the adaptive controller 18 is a recurrence type controller that enables feedback control that compensates for the dynamic behavior change of the engine 1 as described above, and is proposed by I.D.
- An operation amount calculation unit 31 for calculating the KSTR is configured.
- the parameter adjustment section 30 will be described.Landau et al.'S adjustment law generally uses the polynomial of the denominator and numerator of the transfer function B (Z -1) / A (Z -1) of the discrete system to be controlled.
- the adaptive parameter set by the parameter adjuster 30> 6 (j) (j is the number of control cycles) Is represented by a vector (transposed vector) as in equation (33).
- the input ⁇ (j) to the parameter adjustment section 30 is expressed as in equation (34).
- the engine 1 to be controlled by the global feedback control unit 15 has a dead time dp (a time equivalent to three combustion cycles of the engine 1) for three control cycles in the primary system.
- dp a time equivalent to three combustion cycles of the engine 1
- the adaptive parameters to be set are those for SO, r1, r2, r3, and b0. Five (see Fig. 9).
- us and ys in the upper and middle equations of Equation (34) generally represent the input (operating amount) to the controlled object and the output (controlled amount) of the controlled object, respectively.
- the input is the feedback operation amount KSTR
- the output of the control target (engine 1) is the output KACT (detection value of the air-fuel ratio) of the LAF sensor 5
- the input to the parameter adjustment unit 30 is the input to the parameter adjustment unit 30.
- (] ') Is represented by the lower equation of equation (34) (see Fig. 9).
- T T (j) [us (j) us ⁇ j— m— dp + 1), ys CD, ys (j—]
- the adaptive parameter 0 hat is given by the following equation (38). It is calculated from:
- ⁇ (i) ⁇ (g 1) + “(g 1) ⁇ ⁇ (j-dp)-e” (j) (38)
- ⁇ (j) is the adaptive parameter
- the gain matrix that determines the set speed of 0 hats (the order of this matrix is m + n + dp), and e * (j) indicate the estimation error of the adaptive parameter over 0 hats. 3 9),, (4 0).
- r (j ⁇ . " ((i 0 ⁇ 2 ) ⁇ " ( ⁇ 1 ) ⁇ ( ⁇ dp) ⁇ ( ⁇ dp) '' ”(j— ⁇ ) ⁇
- D ( ⁇ ) in the equation (40) is an asymptotically stable polynomial for adjusting the convergence.
- D (Z 1) 1.
- the adaptive parameter 0 hat (s 0, r 1, r 2, r 3, b 0) set by the parameter adjustment unit 30 and the target air space of the exhaust-side main processing unit 13
- the manipulated variable calculator 31 calculates the feedback manipulated variable KSTR by the recurrence formula of the following equation (41).
- the manipulated variable calculator 31 in FIG. 9 is a block diagram showing the calculation of the equation (41).
- KSTR (j) -[KCMD (j) one SO 'KACT (j)- ⁇ 1KSTR)
- the feedback operation amount KSTR obtained by the equation (41) is the output KACT of the LAF sensor 5 and the target air-fuel ratio KCMD.
- the target air-fuel ratio KCMD is obtained in the state where
- the feedback operation amount KSTR that can be used as the feedback correction coefficient KFB is obtained by dividing the feedback operation amount KSTR by the target air-fuel ratio KCMD by the division processing unit 19. .
- the adaptive controller 18 constructed in this manner is a recurrence-type controller that takes into account the dynamic behavior change of the engine 1 to be controlled, as is apparent from the above description. It is a controller written in recurrence form to compensate for the dynamic behavior change of Engine 1. And, more specifically, it can be defined as a controller having a recursive formula-type adaptive parameter adjustment mechanism.
- this type of recursive controller may be constructed using a so-called optimal regulation system. In this case, however, in general, a parameter adjustment mechanism is not provided and the engine is not provided. In order to compensate for the dynamic behavior change of 1, the adaptive controller 18 configured as described above is preferable.
- the PID controller 17 provided in the global feedback control unit 15, like the general PID control, outputs the output KACT of the LAF sensor 5 and its target air-fuel ratio KCMD.
- the output KACT of the LAF sensor 5 becomes equal to the target air-fuel ratio KCMD so that the filter can be operated.
- the first knock operation amount KLAF is set to "1"
- the first knock operation amount KLAF is directly used as the feedback correction coefficient KFB for correcting the fuel injection amount.
- the gains of the proportional term, the integral term and the derivative term are determined from the engine speed NE and the intake pressure PB using a predetermined map.
- the switching unit 20 of the global feedback control unit 15 is used for controlling the combustion of the engine 1 when the cooling water temperature of the engine 1 is low, during high-speed rotation, or when the intake pressure is low.
- the output KACT of the LAF sensor 5 corresponding to the change may be caused by the response delay of the LAF sensor 5, etc. If the reliability is low, or if the operating condition of Engine 1 is extremely stable, such as during idle operation of Engine 1, and high gain control by adaptive controller 18 is not required, PID control
- the feedback operation amount KLAF obtained by the unit 17 is output as the feedback correction amount KFB for correcting the fuel injection amount.
- the feedback operation amount kstr obtained by dividing the feedback operation amount KSTR obtained by the adaptive controller 18 by the target air-fuel ratio KCMD is used to correct the fuel injection amount.
- the adaptive controller 18 functions so as to rapidly converge the output KACT of the LAF sensor 5 to the target air-fuel ratio KCMD with high gain control, so that the combustion of the engine 1 is unstable as described above. If the output KACT of the LAF sensor 5 is unreliable or the reliability of the output KACT of the LAF sensor 5 is low, the control of the air-fuel ratio may become unstable if the feedback manipulated variable KSTR of the adaptive controller 18 is used. Because.
- the operation of the switching unit 20 is disclosed in detail in, for example, Japanese Patent Application Laid-Open No. 8-105354 / US Pat. No. 5,558,075. Therefore, further description is omitted here.
- Engine-side control unit 7 b is carried out as follows: the calculation of the output fuel injection quantity #nT 0U t of each cylinder in the control cycle in synchronism with the crankshaft angle period of the engine 1 (TD C).
- the engine-side control unit 7b reads the outputs of various sensors including the LAF sensor 5 and the O 2 sensor 6 (STEP a;).
- the output VO2 / OUT of the output KACT and 0 2 sensor 6 of the LAF sensor 5 are stored in a memory (not shown) in a time-series manner, including those obtained in their respective past.
- the basic fuel injection amount calculation unit 8 corrects the fuel injection amount corresponding to the engine speed NE and the intake pressure PB according to the effective opening area of the throttle valve, as described above. Is required (STEP b). Further, the first correction coefficient calculating section 9 calculates a first correction coefficient KTOTAL corresponding to the cooling water temperature of the engine 1, the purge amount of the canister, and the like (STEP c).
- the engine-side control unit 7b determines whether the operating mode of the engine 1 uses the target air-fuel ratio KCMD generated by the target air-fuel ratio calculating means 13a of the exhaust-side main processing unit 13 to determine the fuel injection amount.
- a determination process is performed to determine whether or not the operation mode is an operation mode for performing adjustment (hereinafter, referred to as a normal operation mode), and whether or not the operation mode is the normal operation mode is a value “1” or “1”, respectively.
- a normal operation mode an operation mode for performing adjustment
- the operation mode is the normal operation mode is a value “1” or “1”, respectively.
- the O 2 sensor 6 and LAF It is determined whether or not the sensor 5 is activated (STEP d-1, d-2). At this time, if either of them is not activated, it is not possible to obtain the detection data of the 2 sensor 6 or the LAF sensor 5 used for the processing of the exhaust side main arithmetic processing unit 13 with high accuracy. Therefore, the operation mode of engine 1 is not the normal operation mode, and the value of the flag f / prism / on is set to "0" (STEP d-10).
- the ignition timing of the engine 1 is delayed in order to activate the catalyst device 3 immediately after the engine 1 starts. Whether it is controlled to the corner side (STEP d — 4), whether the throttle valve of engine 1 is almost fully open (STEP d — 5), and if fuel supply to engine 1 is stopped (fuel Is determined (STEP d-6). When any of these conditions is satisfied, it is not preferable to control the fuel supply to the engine 1 using the target air-fuel ratio KCMD generated by the exhaust-side main processing unit 13, or Can't control. Accordingly, the operation mode of the engine 1 is not the normal operation mode, and the value of the flag f / prism / on is set to “0” (STEP d—10).
- the rotation speed NE and the intake pressure PB of the engine 1 are respectively within a predetermined range (within a normal range) (STEP d-7, d-8). At this time, if any one is not within the predetermined range, it is not preferable to control the fuel supply of the engine 1 using the target air-fuel ratio KCMD generated by the exhaust-side main processing unit 13. Therefore, the operation mode of the engine 1 is not the normal operation mode, and the value of the flag f / prism / on is set to “0” (STEP d—10).
- the global feedback control unit 15 calculates the feedback operation amount KLAF obtained by the PID controller 17 and the feedback operation amount KSTR obtained by the adaptive controller 18 as the target air-fuel ratio KCMD.
- the switching unit 20 selects one of the feedback operation amounts KLAF or kstr according to the operating condition of the engine 1 from the feedback operation amount kstr divided by (usually adaptive control Select the feedback operation amount kstr of the unit 1 8 side). Then, the selected feedback operation amount KLAF or kstr is changed to the feedback amount for correcting the fuel injection amount. Output as the number of lock corrections KFB.
- a second correction coefficient KCMDM corresponding to the target air-fuel ratio KCMD determined in the above STEP f or STEP g is further calculated by the second correction coefficient calculation unit 10. (STEP j).
- the engine-side control unit 7b adds the first correction coefficient KTOTAL, the second correction coefficient KCMDM, the feedback correction coefficient KFB, and the cylinder-specific fuel injection amount Tim to the basic fuel injection amount Tim obtained as described above.
- the feedback correction coefficient #nKLAF By multiplying by the feedback correction coefficient #nKLAF, the output fuel injection amount #n T out for each cylinder is obtained (STEP k).
- the output fuel injection amount #n Tout for each cylinder is corrected by the adhesion correction unit 23 in consideration of the adhesion of the fuel wall to the intake pipe of the engine 1 (STEP m), the engine 1 It is output to a fuel injector not shown (STEP n).
- the exhaust-side control unit 7a executes a main routine process shown in a flowchart of FIG. 12 in a control cycle of a fixed cycle. I do.
- the exhaust-side control unit 7.a first performs a determination process as to whether or not to execute the arithmetic process in the exhaust-side main arithmetic processing unit 13 described above.
- the value of the flag f / prism / cal is "0" it means that the arithmetic processing in the exhaust-side main arithmetic processing unit 13 is not performed.
- the value of the flag is "1”
- the exhaust-side main arithmetic processing unit 13 is not operated. This means that the arithmetic processing in the processing unit 13 is performed.
- the above determination processing is performed as shown in the flowchart of FIG. That is, it is determined whether or not the O 2 sensor 6 and the LAF sensor 5 are activated (STEP 1-1, 1-2). At this time, when any is not activated, since process is not performed to obtain good detection de Isseki exhaust-side main processor 1 0 using a third processing 2 sensor 6 and the LAF sensor 5 precision , Set the value of the flag f / prism / cal to “0” (STEP 1 — 6). Further, at this time, the value of the flag f / id / reset that specifies whether or not to perform initialization, which will be described later, of the setter 25 is set to "1" (STEP l — 7). Here, when the value of the flag f / id / reset is “1”, it means that the identifier 25 is initialized, and when it is “0”, it means that the initialization is not performed. I do.
- the ignition timing of the engine 1 is determined. It is determined whether or not is controlled to the retard side (STEP 1-4). In the case one of these conditions that are formed upright, and calculate the target air-fuel ratio KCMD as to settle the output V02 / OUT of the O 2 sensor 6 to the target value V02 / TARGET, it The flag f / prism / cal is set to “0” because it is not used to control the fuel supply of Engine 1 (STEP 1-6). Further, at this time, the value of the flag f / id / reset is set to “1” in order to initialize the identifier 25 (STEP 1 — 7).
- the exhaust-side control unit 7 a further identifies the gain coefficients al, a2, and bl by the identifier 25 (update).
- a determination is made as to whether or not to execute the processing, and the value of a flag f / id / cal that defines whether or not the processing can be performed is set (STEP 2).
- the value of the flag f / id / cal is “0”, it means that the identification (update) processing of the gain coefficients al, a2, and bl by the identifier 25 is not performed.
- "1" it means that identification (update) processing is performed.
- the throttle valve of the engine 1 is substantially fully opened and whether or not the fuel supply to the engine 1 is stopped (during fuel cut). . If any of these conditions are satisfied, the gain coefficients al, a2, and bl can be properly identified. Since it is difficult, set the value of the flag f / id / cal to “0”. If none of the above conditions are satisfied, the value of the flag f / id / cal is used to execute the identification (update) processing of the gain coefficient al. A2, bl by the identifier 25. Set to “1”.
- the subtraction processing unit 1 1, 1 2 the output V02 / OUT of the output KACT and 0 2 sensor 6 from the LAF sensor 5 which is stored in a memory (not shown) incorporated Oite in STEP a of FIG. 1 0
- the latest one is selected from the time series data of the above and the deviation outputs kact (k) and V02 (k) are calculated.
- the deviation outputs kact (k) and V02 (k) are stored in a memory (not shown) in the exhaust-side control unit 7a in chronological order, including those calculated in the past.
- the exhaust-side control unit 7a determines the value of the flag f / prism / cal set in STEP1 (STEP4).
- the SLD operation input Usl ( The target deviation air-fuel ratio kcmd) is forcibly set to a predetermined value (STEP 13).
- the predetermined value is, for example, a predetermined fixed value (for example, “0”) or the value of the SLD operation input Usl determined in the previous control cycle.
- the exhaust side control unit 7a adds the reference value FLAF / BASE to the predetermined value of the SLD operation input Usl to perform the current control.
- the target air-fuel ratio KCMD for the cycle is determined (STEP 14), and The process ends.
- the arithmetic processing by the identifier 25 is performed as shown in the flowchart of FIG.
- the values of the above-mentioned identification gain coefficients al hat, a2, h, and bl are set to predetermined initial values (the identification gain coefficient vector ⁇ in equation (4)).
- each component of the matrix P (diagonal matrix) used in the above equation (9) is set to a predetermined initial value.
- the value of the flag f / id / reset is reset to “0”.
- the identifier 25 is calculated for each control cycle in STEP 3 described above, with the current identification gain coefficient al (kl) hat, a2 (k-1) hat, bl (kl) hat.
- the identification error output V02 (k) (Step 5-4).
- the identifier 25 has new identification gain coefficients al hat, a2 hat, After calculating the vector K 0 (k) to be used in determining the bl hat using Equation (9) (Step 5-5), the identification error id / e (k) (the identification error output Calculate the deviation between the V02 hat and the actual deviation output V02 (see equation (7)) (STEP 5-6).
- the identification error ⁇ id / e (k) can be basically calculated according to the above equation (7). In the present embodiment, however, STEP 3 of FIG. From the deviation output V02 calculated for each control cycle in step 5-4 and the identification deviation output V02 calculated for each control cycle in step 5-4. ) _ VO2 (k) hat), and perform filtering with low-pass characteristics to determine the identification error id / e (k).
- the behavior of the target exhaust system E including the catalyst device 3 generally has a low-pass characteristic, so that the gain coefficient al, a2, and bl of the target exhaust system E can be properly specified in the low frequency This is because it is preferable to emphasize the behavior of the side.
- the identification error id / e (k) may be obtained by performing the operation of equation (7).
- the above-mentioned filling is performed, for example, by moving average processing, which is one method of digital filling.
- the identifier 25 uses the identification error id / e (k) determined in STEP 5-6 and the K 6) (k) calculated in STEP 5-5 to obtain the equation (8).
- the identifier 25 calculates the identification gain coefficient al hat a2 hat
- the processing of limiting the values of g, bl, and k (elements of the identification gain coefficient vector ⁇ ) so as to satisfy the specified conditions is performed (STEP 5-8).
- the identifier 25 updates the matrix P (k) by the above equation (10) for the processing of the next control cycle (STEP 5-9), and then executes the processing of the main routine of FIG. Return to.
- the process of limiting the values of the identification gain coefficient al hat, a2 notch, and bl hat is performed by combining the values of the identification gain coefficient al hat, a2 hat with a predetermined combination.
- the processing consists of limiting the value of the coefficient bl to a predetermined range.
- the identification gain coefficient bl (k) calculated in the above STEP 5-7 exceeds the upper limit or the lower limit of the predetermined range, the identification gain coefficient bl (k) Forcibly limit the value of a hat to its upper or lower limit.
- the processing for limiting the identification gain coefficients al knot, a2 knot, knot, bl) knot is performed by the SLD operation input Usl (target deviation air-fuel ratio kcmd) calculated by the sliding mode controller 27, and thus the target This is to ensure the stability of the air-fuel ratio KCMD.
- the kl) hat, a2 (kl) hat, and bl (kl) hat are the values of the identification gain coefficients after performing the limit processing of STEP 5-8 in the previous control cycle.
- the exhaust-side control unit 7a determines the values of the gain coefficients al, a2, and bl (STEP 6 ).
- the value of the flag f / id / cal set in STEP 2 is “1”, that is, when the identification process of the gain coefficients al, a2, and bl by the identifier 25 is performed.
- the values of the gain coefficients al, a2, and bl are the latest identification gain coefficients al (k), a2 (k), and Set the bl (k) hat (with the restriction processing of STEP 5-8).
- the values of the gain coefficients al, a2, and bl are set in advance. It is a predetermined value.
- the exhaust-side control unit 7a performs a calculation process (calculation process of the estimated deviation output V02 bar) by the estimator 26 (STEP 7).
- the estimator 26 firstly obtains the gain coefficients al, a2, and bl determined in STEP 6 (these values are basically the identification gain coefficients al, a, a2, and a2). , B 1, and b) are used in the above equation (13).
- the coefficient values al, 2, i3 j (j-1, ..., d) to be used are calculated in accordance with the definition of the proviso of equation (12).
- the estimator 2 6, the present control cycle previous time series data of the differential output V02 of the STEP 3 Ru is calculated in each control cycle 0 2 sensor 6 - evening V02 (k), VO2 (kl ), and
- the time series data kact (k ′ ′) (j 0,..., Dl) before the current control cycle of the deviation output kact of the LAF sensor 5 and the target given for each control cycle from the sliding mode controller 27
- the estimated deviation output V02 (k + d) value (the deviation after the total dead time d from the time of the current control cycle) Output V02).
- the sliding mode controller 27 firstly outputs the time series data V02 (k + d) bar and VO2 (k + dl) bar of the estimated deviation output V02 bar obtained by the estimator 26 in STEP 7 described above.
- the switching function defined by the equation (25) the value o (k + d) bar after the total dead time d from the current control cycle of the ⁇ bar (this is expressed by the equation (15) )), which is equivalent to the estimated value after the total dead time d of the linear function defined by).
- the value of the switching function ⁇ bar is set within a predetermined allowable range, and the ⁇ (k + d) bar obtained as described above exceeds the upper limit or lower limit of the allowable range.
- the value of each bar ⁇ (k + d) bar is forcibly limited to the upper limit or the lower limit. This is because when the value of the switching function ⁇ bar becomes excessive, the reaching law input Urch becomes excessive.
- the adaptive law input Uadp suddenly changes, the stability of the convergence control of the output V02 / OUT of the second sensor 6 to the target value V02 / TARGET may be impaired.
- the sliding mode controller 27 is obtained by multiplying the value & (k + d) bar of the above switching function ⁇ bar by the cycle ⁇ T (constant cycle) of the control cycle of the exhaust-side control unit 7a.
- (k + d) bar ⁇ ⁇ T is cumulatively added, that is, the ⁇ (k + d) bar calculated in the current control cycle and the period ⁇ T are added to the addition result obtained in the previous control cycle.
- the integrated value of ⁇ bar hereinafter, referred to as the calculation result of the term of ⁇ ( ⁇ bar ⁇ ⁇ ⁇ ) in the equation (27) This integrated value is represented by ⁇ bar).
- the integrated value ⁇ bar is set to fall within a predetermined allowable range, and the integrated value ⁇ bar exceeds the upper limit value or the lower limit value of the allowable range.
- the integrated value ⁇ bar is forcibly limited to the upper limit or the lower limit, respectively. This is because, when the integrated value ⁇ bar becomes excessive, the adaptive law input Uadp obtained by the above equation (27) becomes excessive, and the target value V02 / OUT of the output V02 / OUT of the sensor 2 to the target value V02 / TARGET is obtained. This is because the stability of the convergence control may be impaired.
- the sliding mode controller 27 obtains the time series data VO2 (k + d) of the current value and the past value of the estimated deviation output V02 bar obtained by the estimator 26 in STEP 7 and V02 (k + dl) bar, the switching function ⁇ bar value obtained as described above, the ⁇ (k + d) bar and its integrated value ⁇ ⁇ bar, and the gain coefficients al, a2, bl (these The values are basically the latest identification gain coefficients al (k) hat, a2 (k) hat, bl (k) hat), and the above equations (24), (26) ) And (27), the equivalent control input Ueq, the reaching law input Urch, and the adaptive law input Uadp are calculated, respectively.
- the sliding mode controller 27 adds the equivalent control input Ueq, the reaching law input Urch, and the adaptive law input Uadp to obtain the SLD operation input Usl, that is, the output V02 / OUT of the ⁇ 2 sensor 6.
- the input amount ( target deviation air-fuel ratio kcmd) to the target exhaust system E required to converge the target value to the target value V02 / TARGET.
- the exhaust-side control unit 7a determines the stability of the adaptive sliding mode control by the sliding mode controller 27 (more specifically, the adaptive sliding mode control). Based on ⁇ , a process is performed to determine the control state of the output V02 / OUT of the two sensors 6 (the stability of the SLD control state), and it is determined whether the SLD control state is stable. Set the value of the flag f / sld / stb represented by "1" and "0" (STEP 9).
- the exhaust-side control unit 7a firstly calculates the deviation ⁇ between the current value ⁇ (k + d) bar of the switching function ⁇ bar calculated in STEP 8 and the previous value ⁇ (k + d-1) bar. Calculate the ⁇ bar (this corresponds to the change rate of the switching function ⁇ bar) (STEP 9-1).
- the exhaust-side control unit 7a calculates the product of the above-mentioned deviation ⁇ bar and the current value of the switching function ⁇ bar (k + d) bar ⁇ bar ⁇ hi (k + d) bar (this is the one regarding corresponding to Lyapunov function ⁇ bar 2 second time derivative function) is equal to or less than a predetermined value determined there et beforehand ⁇ ( ⁇ 0) (STE ⁇ 9 - 2).
- the product ⁇ ⁇ bar ⁇ ⁇ (k + d) bar (hereinafter referred to as stability determination parameter Pstb) is described as follows.
- the value of the stability determination parameter Pstb is Pstb> 0. Is basically the value of the switching function ⁇ bar It is in the state of moving away from the force "0".
- the state in which the value of the stability determination parameter P stb becomes P stb ⁇ 0 is basically a state in which the value of the switching function ⁇ bar is converging to the force “0”, or a state in which it is converging. It is.
- the value of the switching function must stably converge to “0” in order to stably converge the control amount to the target value. Therefore, basically, it can be determined that the SLD control state is stable or unstable depending on whether or not the value of the stability determination parameter P stb is equal to or less than “0”.
- the switching function ⁇ bar value contains only a small amount of noise, and the stability determination result is Have an effect.
- the predetermined value ⁇ to be compared with the stability determination parameter P stb in S ⁇ — 9-2 is a positive value slightly larger than “0”.
- the exhaust-side control unit 7a determines that the current value ⁇ (k + d) of the switching function ⁇ bar is It is determined whether it is within the predetermined range (STEP 9-3).
- the state where the current value ⁇ (k + d) bar of the switching function ⁇ bar is not within the predetermined range is a state where the current value ⁇ (k + d) bar is greatly separated from “0”. Therefore, the SLD control state is considered to be unstable. For this reason, In the judgment of STEP 9-3, if the current value of the switching function ⁇ bar (k + d) is not within the predetermined range, the SLD control state is considered to be unstable, and the same as the above case Then, execute the processing of STEP 9-4 and 9-5 to start the timer and set the value of the flag f / sld / stb to “0”.
- the value of the switching function ⁇ bar is limited to a predetermined allowable range in the above-described processing of STEP 8, so that the determination processing of S ⁇ ⁇ 9-3 may be omitted.
- the exhaust-side control unit 7a performs the above-mentioned operation. Is counted down for a predetermined time Atm (STEP 9-6). Then, it is determined whether or not the value of the evening image tm is equal to or less than “0”, that is, whether or not the predetermined time of the initial value TM has elapsed since the start of the evening image tm (STEP). 9—7).
- the stability of the SLD control state is determined, and If it is determined to be stable, the value of the flag f / sld / stb is set to "0". If it is determined to be stable, the value of the flag f / sld / stb is set to "1". Is done.
- the above-described method of determining the stability of the SLD control state is an example, and it is possible to determine the stability by another method. For example, for each predetermined period longer than the control cycle, the frequency at which the value of the stability determination parameter Pstb in each predetermined period becomes larger than the predetermined value ⁇ is counted. If the frequency exceeds a predetermined value, it may be determined that the SLD control state is unstable, and if the frequency is opposite, it may be determined that the SLD control state is stable.
- this limit processing it is determined whether the current value Usl (k) of the SLD operation input Usl calculated in STEP 8 is within a predetermined allowable range, and the current value Usl is determined to be within the allowable range.
- the current value Usl (k) of the SLD operation input Usl is forcibly limited to the upper limit value or the lower limit value, respectively.
- the exhaust-side control unit 7a performs a process of evaluating the deterioration state of the catalyst device 3 (details will be described later) in the deterioration-state evaluation process of the exhaust-side main processing unit 13.
- the sliding mode controller 27 adds the reference value FLAF / BASE to the SLD operation input Usl that has undergone the limit processing in step 1 ⁇
- the target air-fuel ratio KCMD is calculated (STEP 14), and the processing of the current control cycle ends.
- the exhaust side control unit 7a After forcibly setting the value of the SLD operation input Usl to a predetermined value (fixed value or the previous value of the SLD operation input Usl) in the control cycle (STEP 13), the target air-fuel ratio is calculated according to the equation (28). KCMD is calculated (STEP 14), and the processing of the current control cycle ends.
- the target air-fuel ratio KCMD finally determined in STEP 14 is stored in a memory (not shown) in a time-series manner for each control cycle.
- the global feedback controller 15 or the like uses the target air-fuel ratio KCMD determined by the exhaust-side control unit 7a (see STEP f in FIG. 10), the time series The latest one is selected from the target air-fuel ratio KCMD that is stored and stored.
- This evaluation process is performed by the deterioration state evaluation means 13b of the exhaust side control unit 7a as shown in the flowchart of FIG.
- the deterioration state evaluating means 13 b firstly calculates the value of the linear function ⁇ for deterioration evaluation determined by the above equation (15) using the ⁇ 2 sensor 6 calculated by S ⁇ ⁇ 3 in FIG. Calculated from the time series data V02 (k) and VO2 (kl) of the deviation output V02 (current value of deviation output V02 and past value one control cycle before) (STEP 1 2— 1).
- the values of the coefficients si and s2 used in this case are the same as the values of the coefficients sl and s2 that the sliding mode controller 27 uses in step 8 to obtain the value of the switching function ⁇ bar. is there.
- the deterioration state evaluation means 13b judges the value of the flag F / DONE (STEP 12-2).
- the flag F / DONE is a flag that indicates whether or not the evaluation of the deterioration state of the catalyst device 3 has been completed during the current operation of the engine 1 by values “1” and “0”, respectively. Yes, and its value is set to “1” in the processing of STEP 1 2-5 described later.
- the value of the flag F / DONE is initialized to “0” when the engine 1 is started.
- Step 1 2-3 the deterioration state evaluation means 13 b is used for the exhaust gas volume (the flow rate of the exhaust gas flowing through the exhaust pipe 2).
- this process determines whether the exhaust gas volume is maintained in a substantially constant state (hereinafter referred to as a cruise state), and determines whether or not the cruise state is a value “1”, This is the process of setting the value of the flag F / CRS represented by “0”. In this case, in this embodiment, this processing is performed at a cycle (for example, 1 second) longer than the cycle (30 to 100 ms) of the control cycle of the exhaust-side control unit 7a. It is performed as shown in the flowchart of Fig.17.
- the estimated value ABSV (hereinafter referred to as the estimated exhaust gas volume) of the current exhaust gas volume is calculated by the following equation (42). Calculate (STEP 1 2 _ 3 _ 1).
- ABSV-. PB-SVPRA ( ⁇ 2)
- the rotation in the above equation (42) is The number NE (detected value) is divided by “1500”.
- SVPRA is a constant determined in advance according to the displacement of the engine 1 and the like.
- the exhaust gas volume may be estimated from the fuel supply amount of the engine 1 or the intake air amount, or may be directly detected using a flow sensor.
- the exhaust gas volume fluctuation parameter representing the fluctuation state of the exhaust gas volume is obtained.
- One evening Ask for SVMA (STEP 1 2— 3— 2).
- the filtering process is given by the following equation (43).
- the fluctuation parameter overnight SVMA is calculated as a change in the estimated exhaust gas volume ABSV. It represents the rate of formation. Therefore, as the value of the exhaust gas volume fluctuation parameter SVMA is closer to “0”, it means that the estimated exhaust gas volume ABSV has a smaller change with time (the estimated exhaust gas volume ABSV is almost constant). I do.
- Deteriorated state evaluating means 1 3 b is then obtained by squaring the value of the exhaust gas volume variation parameters taken SVMA, i.e., with a predetermined value ⁇ which predetermined squared value SVMA 2 of the fluctuation parameter SVMA (STEP 1 2 — 3— 3).
- the predetermined value ⁇ is a positive value near “0”.
- TMCRSJUD 0 is set to the value of TMCRSJUD in the evening
- the fluctuation state of the exhaust gas volume is determined to be the above-mentioned crucible state, and the value of TMCRSJUD is set to 0. (STEP 1 2 — 3— 8) and change the value of the flag F / CRS Set to “1” (STEP 1 2 — 3 — 9). Then, the process returns to the routine process of FIG.
- the processing described above is the processing of STEP 12-3 in FIG.
- the state in which the square value SVMA2 of the exhaust gas volume fluctuation parameter SVMA is smaller than the SVMA2 by ⁇ is the initial value of the TMCRSJUD. If the cruise state is maintained for a time corresponding to X / TMCRSJST (for example, 10 to 15 seconds), the value of the flag F / CRS is set to “1”. In other cases, the value of the flag F / CRS is set to “0”, assuming that the fluctuation state of the exhaust gas volume is not the closed state.
- the deteriorated state evaluating means 1 3 b carries out the processing of calculating the deterioration evaluating parameter Isseki LSa 2 (STEP 1 2 - 4 ).
- This process is performed as shown in the flowchart of FIG. 18. That is, the deterioration state evaluation means 13 b determines whether or not a predetermined condition for calculating the deterioration evaluation parameter LSa 2 is satisfied. (STEP 1 2 — 4— 1).
- the conditions to be determined here are the above STEP 1 2 —
- the cruising state i.e. a state where the exhaust gas Boriyumu is maintained substantially constant, not performed the calculation of the deterioration evaluating parameter LS o 2 for the following reason. That is, in the cruise state, the output V02 / 0UT of the ⁇ 2 sensor 6 is easily maintained stably at the target value V02 / TARGET, so that the value of the deterioration evaluation linear function ⁇ Even in the advanced state, the change is unlikely to occur. For this reason, in the cruise state, the value of the deterioration evaluation linear function ⁇ is unlikely to tend to correspond to the deterioration state of the catalyst device 3 as described with reference to FIGS. Therefore, in this embodiment, in the cruise state, and is not performed in the calculation of the deterioration evaluating parameter Isseki LS a 2.
- condition judgment of STEP 12-4-1 in addition to the value of the flag F / CRS and the flag f / prism / on, for example, whether the vehicle speed of the vehicle equipped with the engine 1 is within a predetermined range Conditions, such as whether or not a certain amount of time has elapsed since the start of the engine 1 and whether or not the catalyst device 3 is activated, is also determined. If these conditions are not satisfied, Immediately returns to the routine processing of FIG. 16 without performing the processing for calculating the parameter LSa 2 for deterioration evaluation, assuming that the deterioration evaluation condition is not satisfied.
- the deterioration state evaluation method 1 3 b Calculates the squared value ⁇ 2 of the value of the linear function ⁇ for deterioration evaluation obtained for each control cycle of the exhaust-side control unit 7 a in STEP 12-1 of FIG. 16 (S ⁇ ⁇ 1 2 — 4— 2).
- the deterioration state evaluation means 13 b is used to determine the catalyst based on the parameter LSa 2 for deterioration evaluation.
- the deterioration state of the device 3 is evaluated (STEP 12-5). This process is performed as shown in the flowchart of FIG.
- the deterioration state evaluation means 13b determines whether the current value BP (k) of the gain parameter overnight BP is substantially equal to the previous value BP (kl) (whether the gain parameter overnight BP has substantially converged). and determination of the counter whether or not the value of CB1P becomes equal to or larger than a predetermined value CB1CAT (number is a predetermined value of the deterioration evaluating parameter Isseki LS monument 2 look deterioration evaluating value of the linear function ⁇ used in order CB1CAT (STEP 1 2—5—1, 1 2—5—2).
- the battery of the vehicle (not shown) is once removed before the engine 1 is started, or when the engine 1 is started for the first time, such as when the engine 1 is started for the first time, the deterioration during the previous operation when the engine 1 is started is performed. If the data of the evaluation parameter overnight LSo 2 and the gain parameter overnight BP are not retained (when their values are initialized to “0”), the previous step 1 2 — 5—2
- the predetermined value to be compared with the value of the counter CB1P is set to a value larger than the case where the above parameters LSo 2 and BP are held.
- the deterioration evaluation parameters obtained in STEP 1 2—4 in the current control cycle are LSo 2, since become represents the central value of the square values shed second value of the deterioration evaluating linear function Monument, compared with a predetermined threshold value CATAGELMT showing deterioration evaluating parameter LSFf 2 in FIG. 8 Yes (STEP 1 2-5-3).
- the deterioration state of the catalyst device 3 is the above-mentioned “deterioration progressing state” (the state in which the catalyst device 3 needs to be replaced or the catalyst device 3 has deteriorated to the extent that the replacement time is near. ), And notifies the deterioration alarm 29 to that effect (STEP 12-5). Then, the value of the flag F / D0NE, which is represented by a value “1” and “0”, respectively, indicating whether the evaluation of the deterioration state of the catalyst device 3 during the operation of the engine 1 has been completed, is set to “1”. After the setting (STEP 1 2 — 5— 5), the processing of STEP 1 2-5 ends.
- the deterioration state of the catalyst device 3 is the above-mentioned "non-deteriorated state". Without performing the steps described in STEP 1 2—5—5. Set the value of F / DONE to “1” and end the processing of STEP 1 2 — 5.
- the processing described above is the processing performed by the deterioration state evaluation means 13b in STEP 12 of FIG.
- the target air-fuel ratio of the engine 1 (the target value of the air-fuel ratio of the exhaust gas entering the catalyst device 3) is sequentially determined using the processing of the adaptive sliding mode control so as to make V02 / TARGET converge (settle). Further, by adjusting the fuel injection amount of the engine 1 so that the output KACT of the LAF sensor 5 converges to the target air-fuel ratio KCMD, the air-fuel ratio of the engine 1 is feedback-controlled to the target air-fuel ratio KCMD.
- the deteriorated state evaluating means 1 3 b of the exhaust-side starring calculation processing unit 1 3, 0 2 deterioration voted time series data of the differential output V02 of the sensor 6 Linear function ⁇ is obtained sequentially. It is found in the square value sigma 2 of the center value of the deterioration evaluating linear function sigma the deterioration evaluating parameter Isseki LS o 2 as (least squares central value in the present embodiment), sequential statistical processing algorithm of (the embodiment In the embodiment, the weighted least squares algorithm is used. Then, by comparing the threshold CATAGELMT that defines troduction or roughness of the deterioration evaluating parameter Isseki LS a 2, to evaluate the deteriorated state of the catalytic converter 3.
- LS CT 2 in a cruise state in which the exhaust gas volume is maintained substantially constant, that is, in a situation in which the fluctuation of the exhaust gas volume is small and the value of the linear function for deterioration evaluation hardly changes, LS CT 2 is not calculated. Then, in circumstances other than this situation, it calculates the deterioration evaluating parameter Isseki LS a 2, evaluating the deterioration state of the catalytic converter 3. For this reason, the reliability of the deterioration evaluation parameter LSa 2 as a parameter representing the deterioration state of the catalyst device 3 is increased, and the deterioration state of the catalyst device 3 can be accurately evaluated.
- the estimated differential output V02 bar ⁇ 2 sensor 6 estimator 2 6 seek to converge to "0", as a result of their 0 2 Se
- the target air-fuel ratio KCMD is calculated so that the output V02 / OUT of the sensor 6 converges to the target value V02 / TARGET.
- Dead time dl and the object exhaust system E by this, to compensate for the effect of the dead time d2 of the air-fuel ratio manipulating system consisting of the engine 1 and the engine-side control unit 7 b, the output of ⁇ 2 sensor 6 V02 / OUT
- the stability of convergence control to the target value V02 / TARGET can be improved.
- the values of the gain coefficients al, a2, and bl which are parameters of the exhaust system model used by the sliding mode controller 27 and the estimator 26 in the processing, are sequentially identified by the identifier 25,
- the influence of the change in the behavior state of the target exhaust system E on the convergence control to the target value V02 / TARGET of the output VO2 / OUT of the # 2 sensor 6 can be minimized.
- 0 2 Se the output V02 / convergence control of OUT to the eye target value V02 / TARGET of emissions for 6 can be stable and well carried out. Therefore, according to the device of the present embodiment, it is possible to reliably and satisfactorily evaluate the deterioration state of the catalyst device 3 while ensuring the required purification performance of the catalyst device 3.
- the least square center value of the square value ⁇ 2 of the deterioration evaluation linear function ⁇ 2 is set to the parameter LS o 2 for deterioration evaluation.
- the minimum absolute value of the linear function ⁇ The square center value may be obtained as a parameter for deterioration evaluation.
- the absolute value of the linear function ⁇ is obtained instead of the squared value ⁇ 2 of the linear function ⁇ 2 for deterioration evaluation in STEP 12-4 of FIG. 16 and ( ⁇ ) in the equation (29) is obtained.
- the square value ⁇ 2 of the linear function for deterioration evaluation ⁇ or the least square center value of the absolute value is used as a parameter for deterioration evaluation.
- the variance of the value of the linear function ⁇ for deterioration evaluation (more precisely, the variance with respect to “0”, the average value of the squared value ⁇ 2 of the value of the linear function ⁇ for deterioration evaluation), and the standard deviation (the variance of the variance) Square root) may be obtained as a parameter for deterioration evaluation.
- the linear function ⁇ is a deterioration evaluating, but determined by the formula for the two time series de Isseki variable component of the differential output V02 of ⁇ 2 sensor 6 (1 5), further
- a linear function for deterioration evaluation may be defined by a linear function using the time series data of many deviation outputs VO2 as variable components.
- the switching function for sliding mode control can be defined by a linear function in which the time series data of the deviation output VO2 included in the linear function for deterioration evaluation is replaced with the time series data of the estimated deviation output V02 bar. It is suitable.
- deterioration evaluating linear function for example differential output of the formula (1 5) V02 (k) , V02 (k- 1) a ⁇ 2 output V02 / OUT of the sensor 6 (k), V02 / OUT (k- 1 It may be determined by the formula that is replaced with).
- the central value of the value of the linear function for deterioration evaluation is basically “(sl + s2) ⁇ VO2 / TARGET”.
- the center value (sl + s2) such as the square value of the deviation between the center value (sl + s2) and V02 / TARGET and the value of the linear function for deterioration evaluation or the least square center value of the absolute value.
- the deterioration state of the catalyst device 3 can be evaluated in the same manner as in the first embodiment. Can be.
- Is used Raniwa for example the formula (2 5) of the switching function ⁇ bar, i.e., the 0 2 deterioration evaluating linear function of estimated differential output VO2 linear function to the series data and variable components when the bars of the sensor 6 You may.
- the actual deviation output V02 of the two- sensor 6 is larger than the estimated deviation output V02, which is an estimated value of the deviation output V02 of the second sensor 6 after the total dead time d, which is an estimated value after the total dead time d.
- the use of the degradation evaluation linear function ⁇ of the equation (15) in which is a variable component allows the actual state of the catalytic converter 3 to be better reflected in the linear function ⁇ . Is considered preferable.
- the square value ⁇ 2 of the linear function for deterioration evaluation is used to evaluate the deterioration state of the catalyst device 3.
- the linear function ⁇ 2 The degradation state of the catalyst device 3 is determined by using the product of the value of ⁇ and the rate of change (this is the stability determination parameter P stb used in STEP 9 above to determine the stability of the SLD control state). It is also possible to evaluate. In this case as well, for example, if the variance of the product (more generally, the value indicating the degree of variation in the value of the product) is obtained as a parameter for deterioration evaluation, the catalyst device is determined based on the value of the parameter for deterioration evaluation. It is possible to evaluate the deterioration state of 3.
- the deterioration state of the catalyst device 3 is evaluated by dividing the deterioration state into the “deterioration progress state” and the “non-deterioration state”. if much to be al the threshold value to be compared with the LS a 2, it is also possible to evaluate fractionated into many deterioration degree to be al the deteriorated state of the catalytic converter 3. Then, it is also possible to give different notifications according to the degree of deterioration of each.
- the algorithm of the sliding mode control is constructed based on the exhaust system model represented by the discrete time system. However, based on the model representing the target exhaust system E by the continuous time system. It may be constructed. At this time, switching function for Suraidi ring mode control may be a representation of example ⁇ 2 differential output V02 of the sensor 6 and the linear function to the change rate and a variable component.
- the processing of the adaptive sliding mode control is used to calculate the target air-fuel ratio KCMD.
- the processing of the sliding mode control without using the adaptive law (adaptive algorithm) is used. Is also good.
- the target air-fuel ratio KCMD may be obtained by an equation obtained by removing the term of the adaptive law input Uadp from the equation (28).
- the estimator 26 uses the following equation (44) in which “kcmd” and “d” in the above equation (12) are replaced with “kact” and “dl”, respectively, and As in the embodiment, the estimated value V02 (k + dl) of the deviation output V02 of the ⁇ 2 sensor 6 after the dead time dl is sequentially obtained for each control cycle.
- V02 (k + d1) a1V02 (k) + ⁇ ⁇ V02 (k ⁇ 1) + ⁇ ⁇ kactfk-j) (44)
- the sliding mode controller 27 obtains the equivalent control input Usl and the reaching law input Urch by the equations in which “d” is replaced by “dl” in the equations (24) to (27). Then, the adaptive law input Uadp is obtained for each control cycle, and by adding them, the target deviation air-fuel ratio kcmd is obtained. In this way, the target air-fuel ratio KCMD that compensates for the effect of the dead time dl of the target exhaust system E can be obtained.
- the processing of the identifier 25, the degradation state evaluation means 13b, and the engine-side control unit 7b may be the same as that of the first embodiment.
- the estimator 26 may be omitted.
- the identifier 25 is provided.
- the gain coefficients al, a2, and bl of the exhaust system model may be set to predetermined fixed values, The values of the gain coefficients al, a2, and bl may be appropriately set using a map or the like based on the rotation speed of the engine 1, the intake pressure, and the like.
- the first embodiment uses the exhaust gas sensor and to 0 2 sensor 6 downstream of the catalytic converter 3, exhaust gas sensor, in order to ensure the required exhaust gas purifying capability of the catalytic converter 3 is controlled
- Other sensors may be used as long as they can detect the concentration of a specific component of the exhaust gas downstream of the catalytic device to be performed.
- Nyu_ ⁇ chi sensor if if that controls the catalytic converter downstream of the carbon monoxide in the exhaust gas (CO) is controlled C_ ⁇ sensor, nitrogen oxides (New Omicron chi), hydrocarbons ( HC) is controlled using an HC sensor.
- the purification performance of the catalyst device is maximized, regardless of whether the concentration of any of the above gas components is detected. Further, when a reduction catalyst device or an oxidation catalyst device is used, the purification performance can be improved by directly detecting the gas component to be purified.
- 0 is output V02 / OUT 2 sensor 6 using the processing of the scan Raidi Ngumo de control as a feedback control technique for converging to the target value V02 / TARGET, other feedback control hand It is also possible to evaluate the deterioration state of the catalyst device 3 while controlling the output V02 / OUT of the second sensor 6 to the target value V02 / TARGET by the processing of the method.
- an embodiment in this case will be described as a second embodiment with reference to FIGS.
- the present embodiment is different from the first embodiment only in the functional configuration and processing of the exhaust-side control unit 7a, and thus the same components and the same components as those in the first embodiment. Detailed description of the processing part is omitted by using the same drawings and reference numerals as in the first embodiment.
- FIG. 20 is a functional configuration of the exhaust-side control unit 7a in the present embodiment.
- the exhaust-side control unit 7 a in the present embodiment the same as in the first embodiment, the output of the downstream side of ⁇ 2 sensor 6 of the catalytic converter 3 (see FIG. 1) V02 /
- a process for sequentially generating a target air-fuel ratio KCMD (a target value of the air-fuel ratio detected by the LAF sensor 5) so that OUT converges to the target value V02 / TARGET, and a process for evaluating the deterioration state of the catalyst device 3. are performed in a predetermined control cycle.
- the control cycle of the exhaust-side control unit 7a is a control cycle having a constant cycle, as in the first embodiment.
- Degradation state evaluation means 13b for controlling the operation of the heater 29 is provided in the same manner as in the first embodiment, while the PID control, which is one method of feedback control, is obtained from the data of the deviation output VO2.
- the target air-fuel ratio calculating means 30 for sequentially calculating the target air-fuel ratio KCMD using the process of (proportional Z-integral differential control) is provided as the air-fuel ratio manipulated variable determining means.
- the processing contents of the subtraction processing unit 12 and the deterioration state evaluation means 13b are the same as those of the first embodiment.
- the values of the coefficients si and s2 of the deterioration evaluation linear function ⁇ (see STEP 12-1 in FIG. 16) required in the processing of the deterioration state evaluation means 13b are, for example, The values may be the same as those used in the first embodiment.
- the target air-fuel ratio calculating means 30 controls the air-fuel ratio of the engine 1 in accordance with the target air-fuel ratio KCMD calculated as described later
- the value of the deterioration evaluation linear function ⁇ However, the tendency shown in FIGS. 5 to 7 above is remarkable for the deteriorated state of the catalyst device 3.
- the values of the coefficients sl and s2, which occur in the above, may be set through experiments and the like.
- the target air-fuel ratio calculating means 3 sequentially using ⁇ 2 process PID control the air-fuel ratio manipulated variable Upid the differential output V02 is required to converge to "0" of the sensor 6 (the details will be described later)
- the PID controller 31 generates the air-fuel ratio manipulated variable U pid and a predetermined air-fuel ratio reference value KBS to calculate a target air-fuel ratio KCMD.
- the air-fuel ratio reference value KBS to be added to the air-fuel ratio manipulated variable Upid is the central air-fuel ratio of the target air-fuel ratio KCMD, and corresponds to the reference value FLAF / BASE in the first embodiment.
- the air-fuel ratio reference value KBS is a value in the vicinity of the stoichiometric air-fuel ratio appropriately determined from the detected values of the rotation speed NE of the engine 1 and the intake pressure PB using a preset map. It is.
- the configuration other than the exhaust-side control unit 7a described above (the functional configuration of the engine-side control unit 7b and the configuration of the exhaust system of the engine 1) is exactly the same as that of the first embodiment.
- the processing of the engine-side control unit 7b is the same as that of the first embodiment, and the processing (the fuel injection amount of engine 1) shown in the flowcharts of FIGS. 10 and 11 is used.
- the adjustment process is sequentially executed by the engine-side control unit 7b in a control cycle synchronized with TDC (crank angle cycle).
- the engine-side control unit 7b reads in step f in Fig. 10
- the target air-fuel ratio KCMD is the latest target air-fuel ratio KCMD calculated as described later by the target air-fuel ratio calculating means 30 of the exhaust-side control unit 7a.
- the exhaust-side control unit 7 In a the main routine processing shown in FIG. 21 is executed in a certain control cycle in parallel with the processing of the engine-side control unit 7b.
- the exhaust-side control unit 7a determines the air-fuel ratio reference value KBS from the current rotational speed NE of the engine 1 and the intake pressure PB using a map (STEP 21).
- the subtraction processing unit 1 select the latest from the time-series data of the output V02 / OUT of FIG 1 0 is write or and stored in a memory (not shown) taken at STEP a 0 2 sensor 6 To calculate the deviation output V02 (k).
- the deviation output V02 (k), including the one calculated in the past (specifically, the deviation output V02 (k-1) calculated in the previous control cycle) is stored and held in a memory (not shown).
- the exhaust-side control unit 7a executes the processing of the target air-fuel ratio calculating means 30 in STEPS 24 to 27.
- PID controller 3 1 of the target air-fuel ratio calculating means 3 0 is first ⁇ 2 proportional term relating to the differential output V02 of the sensor 6 in the processing of the PID control to converge to "0", the integral term, and
- the values of the gain coefficients KVP, KVI, KVD of the differential terms are determined from the current rotational speed NE of the engine 1 and the intake pressure PB using a predetermined map (STEP 24).
- PID controller 3 1 is provided with a current value of the differential output VO2 of the O 2 sensor 6 determined by the STEP 2 3 V02 (k) and preceding value V02 (k-1), the latest determined in STEP 2 4
- the current values VREFP (k) and VREFI of the proportional, integral, and derivative terms, respectively are calculated. (k) and VREFD (k).
- the air-fuel ratio operation is performed.
- the basic manipulated variable VREF on which the quantity Usl is based is found (STEP 25).
- VREFP (k) V02 (k) KVP (45)
- VREFI (k) VREFI (k-1) + V02 (k) ⁇ KVI (46)
- VREFD (k) (V02 (k) — 02 (k— 1)) * KVD (47)
- the PID controller 31 performs a limit process on the basic manipulated variable VREF (STEP 26). In this limit process, if the basic manipulated variable VREF obtained in STEP 25 exceeds a predetermined upper limit or lower limit, the value of the basic manipulated variable VREF is forcibly increased, respectively. Set the limit or lower limit.
- the PID controller 31 outputs the basic manipulated variable that has been subjected to the above-described limit processing.
- VREF for example, an air-fuel ratio operation amount Upid is obtained using a predetermined data table as shown in FIG. 22 (STEP 27).
- the data table of FIG. 22 basically determines that the larger the basic manipulated variable VREF, the greater the air-fuel ratio manipulated variable Upid.
- the 0 2 sensor 6 value of the output V02 / OUT targets value V02 / TARGET basic manipulated variable VREF obtained by the PID controller 3 1 in a state such as that substantially converged in the vicinity of the In the range (the range denoted by reference numeral S in FIG. 22), the change in the air-fuel ratio manipulated variable Upid with respect to the change in the basic manipulated variable VREF is small, and the air-fuel ratio manipulated variable Upid is maintained at a value near “0”.
- the target air-fuel ratio calculating means 30 After calculating the air-fuel ratio manipulated variable Upid in this way, the target air-fuel ratio calculating means 30 then adds the air-fuel ratio manipulated variable Upid to the air-fuel ratio determined in STEP 21 by the addition processing section 32.
- the target air-fuel ratio KCMD (k) in the current control cycle is obtained by adding the reference value KBS (STEP 28).
- the target air-fuel ratio KCMD obtained in this manner is stored in a memory (not shown) in time series in each control cycle of the exhaust-side control unit 7a.
- the target air-fuel ratio KCMD is read by the engine-side control unit 7b in STEP f of FIG. 10, the latest one is selected from the target air-fuel ratio KCMD stored and held as described above. You.
- the exhaust-side control unit 7a is deactivated by the deterioration state evaluation means 13b.
- a process for evaluating the deterioration state of the catalytic converter 3 is executed (STEP 29), and the process of the current control cycle is ended.
- the processing executed by the deterioration state evaluating means 13b is exactly the same as that of the first embodiment. That is the degradation state evaluating means 1 3 b is time-series data V02 for the differential output V02 of the O 2 sensor 6 obtained in each control cycle in the STEP 2 3 (k), using said V02 (k-1)
- the processing of the flowcharts in FIGS. 16 to 19 is executed as described above. With this, it is evaluated whether the catalyst device 3 is in the “deterioration progressing state” or the “non-deterioration state”. You.
- the engine is configured so that the output V02 / OUT of the O 2 sensor 6 downstream of the catalyst device 3 converges to the target value VO2 / TARGET. While operating the air-fuel ratio of 1, the deterioration state of the catalyst device 3 is evaluated. Therefore, it is possible to evaluate the deterioration state of the catalyst device 3 while securing appropriate purification performance of the catalyst device 3.
- the correlation with the deterioration state of the catalyst device 3 is the same as in the first embodiment. it is high and can be appropriately evaluate the deteriorated state of the catalytic converter 3 based on a high degradation of reliability evaluation parameter Isseki LS o 2.
- the exhaust-side control unit 7a performs processing using a control cycle with a fixed period. However, similar to the engine-side control unit 7b, processing is performed in synchronization with TDC. Alternatively, the processing may be performed in a control cycle having a cycle of a predetermined number (multiple times) of 1 TDC.
- this embodiment also describes the first embodiment. Various modifications similar to the modifications described above are also possible. Industrial applicability
- the present invention can automatically and appropriately evaluate the deterioration state of a catalyst device such as a three-way catalyst provided in an exhaust system of an internal combustion engine mounted on an automobile, a hybrid vehicle, and the like. It can be used effectively when notifying the evaluation results.
- a catalyst device such as a three-way catalyst provided in an exhaust system of an internal combustion engine mounted on an automobile, a hybrid vehicle, and the like. It can be used effectively when notifying the evaluation results.
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- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Exhaust Gas After Treatment (AREA)
- Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)
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Description
Claims
Priority Applications (7)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
MXPA02006209A MXPA02006209A (es) | 1999-12-22 | 2000-12-21 | Controlador de proporcion de aire-combustible para motores de combustion interna. |
ES00987695T ES2304994T3 (es) | 1999-12-22 | 2000-12-21 | Aparato para controlar la relacion aire-carburante en un motor de combustion interna. |
EP00987695A EP1243769B1 (en) | 1999-12-22 | 2000-12-21 | Air-fuel ratio controller for internal combustion engines |
BR0016604-9A BR0016604A (pt) | 1999-12-22 | 2000-12-21 | Aparelho de controle da relação ar - combustìvel para um motor de combustão interna |
DE60038744T DE60038744T2 (de) | 1999-12-22 | 2000-12-21 | Steuereinrichtung für das luft-kraftstoff-verhältnis einer brennkraftmaschine |
CA002395582A CA2395582C (en) | 1999-12-22 | 2000-12-21 | Air-fuel ratio control apparatus for internal combustion engine |
US10/168,685 US6698186B2 (en) | 1999-12-22 | 2000-12-21 | Air-fuel ratio controller for internal combustion engines |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
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JP11/365604 | 1999-12-22 | ||
JP36560499 | 1999-12-22 | ||
JP2000139860A JP3967524B2 (ja) | 1999-12-22 | 2000-05-12 | 内燃機関の空燃比制御装置 |
JP2000/139860 | 2000-05-12 |
Publications (1)
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WO2001046569A1 true WO2001046569A1 (fr) | 2001-06-28 |
Family
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Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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PCT/JP2000/009116 WO2001046569A1 (fr) | 1999-12-22 | 2000-12-21 | Régulateur de rapport air-carburant de moteurs thermiques |
Country Status (13)
Country | Link |
---|---|
US (1) | US6698186B2 (ja) |
EP (1) | EP1243769B1 (ja) |
JP (1) | JP3967524B2 (ja) |
KR (1) | KR100739534B1 (ja) |
CN (1) | CN1274950C (ja) |
BR (1) | BR0016604A (ja) |
CA (1) | CA2395582C (ja) |
DE (1) | DE60038744T2 (ja) |
ES (1) | ES2304994T3 (ja) |
MX (1) | MXPA02006209A (ja) |
MY (1) | MY122697A (ja) |
TW (1) | TW452629B (ja) |
WO (1) | WO2001046569A1 (ja) |
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JP6408363B2 (ja) * | 2014-12-03 | 2018-10-17 | 日本碍子株式会社 | 触媒劣化診断方法 |
JP6401595B2 (ja) * | 2014-12-03 | 2018-10-10 | 日本碍子株式会社 | 触媒劣化診断方法 |
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Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH06101455A (ja) * | 1992-09-18 | 1994-04-12 | Honda Motor Co Ltd | 内燃エンジンの触媒劣化検知装置 |
JPH06173661A (ja) * | 1992-12-09 | 1994-06-21 | Toyota Motor Corp | 触媒劣化検出装置 |
JPH0777481A (ja) * | 1993-09-08 | 1995-03-20 | Hitachi Ltd | 内燃機関の故障診断装置 |
JPH10205376A (ja) * | 1996-11-19 | 1998-08-04 | Honda Motor Co Ltd | 排気ガス浄化用触媒装置の劣化判別方法 |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3218731B2 (ja) * | 1992-10-20 | 2001-10-15 | 三菱自動車工業株式会社 | 内燃エンジンの空燃比制御装置 |
US5758490A (en) * | 1994-12-30 | 1998-06-02 | Honda Giken Kogyo Kabushiki Kaisha | Fuel metering control system for internal combustion engine |
US5732552A (en) | 1995-02-10 | 1998-03-31 | Mitsubishi Jidosha Kogyo Kabushiki Kaisha | Apparatus for deterioration diagnosis of an exhaust purifying catalyst |
JP3261038B2 (ja) | 1996-04-05 | 2002-02-25 | 本田技研工業株式会社 | 内燃機関の空燃比制御装置 |
JP3354088B2 (ja) * | 1997-09-16 | 2002-12-09 | 本田技研工業株式会社 | 内燃機関の排気系の空燃比制御装置 |
US6449944B1 (en) * | 1998-07-17 | 2002-09-17 | Honda Giken Kogyo Kabushiki Kaisha | Method of judging deterioration of emission gas control catalyst device |
JP3773684B2 (ja) * | 1999-02-09 | 2006-05-10 | 本田技研工業株式会社 | 内燃機関の空燃比制御装置 |
JP4312325B2 (ja) * | 1999-12-28 | 2009-08-12 | 本田技研工業株式会社 | 排ガス浄化用触媒装置の劣化状態評価方法 |
KR20040046822A (ko) * | 2002-11-28 | 2004-06-05 | 현대자동차주식회사 | 차량 내구에 따른 공연비 제어방법 |
-
2000
- 2000-05-12 JP JP2000139860A patent/JP3967524B2/ja not_active Expired - Lifetime
- 2000-12-21 EP EP00987695A patent/EP1243769B1/en not_active Expired - Lifetime
- 2000-12-21 MY MYPI20006095A patent/MY122697A/en unknown
- 2000-12-21 MX MXPA02006209A patent/MXPA02006209A/es active IP Right Grant
- 2000-12-21 US US10/168,685 patent/US6698186B2/en not_active Expired - Fee Related
- 2000-12-21 CN CNB008191255A patent/CN1274950C/zh not_active Expired - Fee Related
- 2000-12-21 BR BR0016604-9A patent/BR0016604A/pt active Search and Examination
- 2000-12-21 CA CA002395582A patent/CA2395582C/en not_active Expired - Fee Related
- 2000-12-21 DE DE60038744T patent/DE60038744T2/de not_active Expired - Lifetime
- 2000-12-21 ES ES00987695T patent/ES2304994T3/es not_active Expired - Lifetime
- 2000-12-21 KR KR1020027008097A patent/KR100739534B1/ko not_active IP Right Cessation
- 2000-12-21 TW TW089127538A patent/TW452629B/zh active
- 2000-12-21 WO PCT/JP2000/009116 patent/WO2001046569A1/ja active IP Right Grant
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH06101455A (ja) * | 1992-09-18 | 1994-04-12 | Honda Motor Co Ltd | 内燃エンジンの触媒劣化検知装置 |
JPH06173661A (ja) * | 1992-12-09 | 1994-06-21 | Toyota Motor Corp | 触媒劣化検出装置 |
JPH0777481A (ja) * | 1993-09-08 | 1995-03-20 | Hitachi Ltd | 内燃機関の故障診断装置 |
JPH10205376A (ja) * | 1996-11-19 | 1998-08-04 | Honda Motor Co Ltd | 排気ガス浄化用触媒装置の劣化判別方法 |
Non-Patent Citations (1)
Title |
---|
See also references of EP1243769A4 * |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2003023202A1 (fr) | 2001-09-05 | 2003-03-20 | Honda Giken Kogyo Kabushiki Kaisha | Dispositif d'evaluation de l'etat de deterioration d'un equipement de regulation d'emission de gaz d'echappement |
US6978598B2 (en) | 2001-09-05 | 2005-12-27 | Honda Giken Kogyo Kabushiki Kaisha | Deteriorated state evaluation device for exhaust emission control equipment |
Also Published As
Publication number | Publication date |
---|---|
MY122697A (en) | 2006-04-29 |
ES2304994T3 (es) | 2008-11-01 |
CA2395582A1 (en) | 2001-06-28 |
KR100739534B1 (ko) | 2007-07-13 |
CN1434896A (zh) | 2003-08-06 |
EP1243769A4 (en) | 2006-01-11 |
JP3967524B2 (ja) | 2007-08-29 |
CN1274950C (zh) | 2006-09-13 |
US6698186B2 (en) | 2004-03-02 |
DE60038744T2 (de) | 2009-07-23 |
DE60038744D1 (de) | 2008-06-12 |
US20030093989A1 (en) | 2003-05-22 |
BR0016604A (pt) | 2003-06-24 |
JP2001241349A (ja) | 2001-09-07 |
CA2395582C (en) | 2008-09-23 |
MXPA02006209A (es) | 2003-03-27 |
EP1243769B1 (en) | 2008-04-30 |
KR20020072559A (ko) | 2002-09-16 |
EP1243769A1 (en) | 2002-09-25 |
TW452629B (en) | 2001-09-01 |
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