JP4275046B2 - Engine control device - Google Patents

Description

  The present invention detects (estimates), directly or indirectly, the amount of greenhouse gas emissions such as carbon dioxide emitted from the engine (in the combustion chamber and downstream of the catalyst), and detects engine differences (individual differences). The present invention relates to an engine control apparatus that can cope with performance differences due to changes over time and the like, and that can effectively suppress an increase in greenhouse gas emissions.

In recent years, there has been a demand for low fuel consumption engines in automobiles against the background of global warming issues and energy issues. The lean burn engine is the best example. For example, the direct injection engine injects fuel directly into the combustion chamber, stratifies the air-fuel mixture, and enables combustion at an air-fuel ratio of 40 or more. It is an engine that is more effective in reducing fuel consumption than an engine that operates at a fuel ratio. In lean burn engines, the amount of carbon dioxide (CO ₂ ), which is a greenhouse gas, is also reduced, but the amount of emissions is quantitative, as is the case with HC, CO, and NOx, where emissions are determined by exhaust gas regulations. It is being limited to. HC, CO, NOx is onboard, and is equipped with a device for notifying the driver or the like when the discharge amount exceeds a predetermined value. On the other hand, with respect to CO ₂ emissions, there is no device that estimates (or detects) the emissions on-board and informs the driver etc. on the background that diagnostic regulations are not in full swing. Is real.

  Conventionally, for example, in Patent Document 1 below, as a device for predicting carbon dioxide emitted from a general household, future weather is based on the correlation between weather conditions in the past predetermined period and carbon dioxide emissions. An apparatus for predicting future carbon dioxide emissions from the prediction is disclosed. However, the present apparatus predicts, for example, carbon dioxide emissions of ordinary households based on weather conditions, and therefore cannot detect the greenhouse gas of the automobile engine on board.

  Patent Document 2 below discloses an apparatus that calculates carbon dioxide emission from construction materials and construction energy at the construction stage of a water treatment facility. However, this apparatus is specialized for water treatment facilities, and uses construction materials and construction energy as input information. Therefore, it is not possible to detect the greenhouse gas of the automobile engine on board.

  Further, in Patent Document 3 below, a gas analyzer that measures the concentration of greenhouse gas contained in the exhaust gas, a flow meter that calculates the flow rate of the exhaust gas, and the measured greenhouse gas concentration and the exhaust gas flow rate are used. An apparatus for obtaining greenhouse gas emission amount and calculating greenhouse gas emission cost P based on an integrated value of greenhouse gas emission amount is disclosed. However, this device is equipped with a device for directly detecting greenhouse gases, and the size of the device is also increased. There is a problem from the aspect.

In view of the above circumstances, the present invention is capable of detecting directly or indirectly the amount of greenhouse gas discharged from an automobile engine, and can be used for suppressing greenhouse gas emissions. An object of the present invention is to provide a control device.
JP 2003-344555 A JP 2004-126843 A JP 2003-76747 A

  In order to achieve the above object, the first aspect of the engine control apparatus according to the present invention directly or indirectly detects the amount of greenhouse gas discharged from the engine (combustion chamber and / or downstream of the catalyst). A greenhouse gas emission detection means is provided (see FIG. 1).

Ie, provided with a means for directly or indirectly detecting (estimating) the emissions of greenhouse gases contained in exhaust gas discharged from the combustion chamber and / or a catalyst downstream of the engine, constantly or predetermined frequency online Thus, greenhouse gas emissions are detected (estimated). The detection means may be a sensor that can directly detect greenhouse gases as described later, or may be detected indirectly by estimation from the output of an existing sensor as described later. The former is advantageous in terms of accuracy, and the latter is advantageous in terms of cost. Further, the exhaust passage of the engine is generally provided with a catalyst for purifying some exhaust gas components such as HC, CO, NOx and the like. For example, in the case of a catalyst having three-way performance, carbon dioxide is generated when a reducing agent such as HC or CO is oxidized. At this time, the carbon dioxide concentration downstream of the catalyst may increase more than that of engine out (exhaust gas discharged from the combustion chamber). Therefore, in the first aspect, not only the detection of the greenhouse gas in the engine-out exhaust gas but also the detection of the greenhouse gas generated by the chemical reaction in the catalyst is performed, and the tail pipe (from the catalyst in the exhaust passage) is detected. In the downstream part), it is proposed to more accurately detect the amount of greenhouse gas emitted.

The second aspect of the engine control apparatus according to the present invention is provided with a diagnostic means for performing deterioration diagnosis of the individual engine device according to emissions of the greenhouse gases individually, the greenhouse gas emissions detection means, the diagnostic Based on the diagnostic result of the means, the greenhouse gas emission is indirectly detected (see FIG. 2).

  That is, for example, carbon dioxide is the largest greenhouse gas emission, but as described above, carbon dioxide changes depending on the operating air-fuel ratio of the engine (the air-fuel ratio of the air-fuel mixture used for combustion), The more lean, the less. Therefore, for example, there is provided a means for diagnosing the state or performance of an engine device related to lean operation, and calculating (indirectly detecting) the carbon dioxide emission from the lean operation performance determined according to the diagnosis result. Is.

  According to a third aspect of the engine control apparatus of the present invention, the greenhouse gas emission detection means detects the amount of carbon dioxide emitted from the engine directly or indirectly (FIG. 3). reference).

  That is, as described above, it is clearly stated that carbon dioxide emission is detected as the most important greenhouse gas.

  According to a fourth aspect of the engine control apparatus of the present invention, the greenhouse gas emission detection means directly or indirectly detects the concentration of carbon dioxide discharged from the combustion chamber of the engine and / or downstream of the catalyst. Carbon dioxide concentration detecting means, and exhaust gas flow rate detecting means for directly or indirectly detecting the exhaust gas flow rate discharged from the combustion chamber of the engine and / or downstream of the catalyst (see FIG. 4).

  That is, the carbon dioxide emission is determined from the carbon dioxide concentration in the exhaust gas and the exhaust gas flow rate.

According to a fifth aspect of the engine control apparatus of the present invention, the exhaust gas flow rate detecting means directly or indirectly detects the exhaust gas flow rate per unit time discharged from the combustion chamber of the engine and / or downstream of the catalyst. To be done.
That is, by changing the exhaust gas flow rate to the exhaust gas flow rate per unit time, it corresponds to a change in the exhaust gas flow rate during a transient operation or the like.

  According to a sixth aspect of the engine control apparatus of the present invention, the carbon dioxide concentration detection means includes a carbon dioxide sensor disposed in the exhaust passage of the engine, and the carbon dioxide concentration is directly detected by the sensor. To be done.

  That is, it is specified that the carbon dioxide concentration detection means is directly detected by a carbon dioxide sensor.

  In a seventh aspect of the engine control apparatus according to the present invention, the carbon dioxide concentration detecting means indirectly detects the carbon dioxide concentration based on an operating state of the engine.

  That is, the carbon dioxide concentration detection means does not directly detect the carbon dioxide concentration, but detects an engine operating state correlated with the carbon dioxide concentration from an existing sensor or the like, and based on this operating state, the carbon dioxide concentration Is indirectly detected (estimated). Examples of the engine operating state include engine speed, engine torque, air-fuel ratio, EGR rate, and the like.

  According to an eighth aspect of the engine control apparatus of the present invention, the carbon dioxide concentration detection means includes a means for directly or indirectly detecting the carbon dioxide concentration discharged from the combustion chamber of the engine, and a new catalyst. And means for directly or indirectly detecting the concentration of carbon dioxide produced (see FIG. 6).

  That is, as described above, for example, when a three-way catalyst is provided in the exhaust passage of an engine, carbon dioxide is generated when HC, CO, etc. are oxidized in the catalyst. At this time, the carbon dioxide concentration downstream of the catalyst increases more than that of engine out (exhaust gas discharged from the combustion chamber). Therefore, in the eighth aspect, not only the detection of the greenhouse gas in the engine-out exhaust gas but also the detection of the greenhouse gas generated by the chemical reaction in the catalyst is performed, and the tail pipe (downstream from the catalyst in the exhaust passage) is detected. (Part) proposes more accurate detection of the amount of greenhouse gas emissions.

  According to a ninth aspect of the engine control apparatus of the present invention, at least one of the engine operating states in the seventh aspect is an engine operating air-fuel ratio.

  That is, the engine operating air-fuel ratio is clearly specified as the best engine operating state correlated with the carbon dioxide concentration.

  According to a tenth aspect of the engine control apparatus of the present invention, the carbon dioxide concentration detecting means according to the eighth aspect is the catalyst based on the catalyst inlet or the air-fuel ratio inside the catalyst detected directly or indirectly. The newly generated carbon dioxide concentration is indirectly detected (estimated).

  That is, it is specified that the air-fuel ratio at the catalyst inlet or inside the catalyst is detected directly or indirectly as the best engine operating state correlated with the concentration of carbon dioxide produced in the catalyst.

  In an eleventh aspect of the engine control apparatus according to the present invention, the carbon dioxide concentration detection means in the eighth aspect is based on the catalyst temperature detected directly or indirectly, and the carbon dioxide concentration newly generated by the catalyst. The carbon concentration is detected indirectly.

  That is, as described above, for example, when HC, CO or the like is oxidized in a catalyst having ternary performance, carbon dioxide is generated, and the catalyst is activated at a predetermined temperature or higher. Therefore, the amount of carbon dioxide produced by the catalyst is indirectly detected (estimated) based on the catalyst temperature.

  According to a twelfth aspect of the engine control apparatus of the present invention, the diagnosis means has at least one state of an electric throttle valve, a fuel injection valve, an EGR valve, a fuel pump, and a lean NOx catalyst as the engine device. Or it is made to diagnose performance.

  That is, as described above, carbon dioxide changes depending on the operating air-fuel ratio of the engine, and decreases as the leaner. Therefore, for example, engine devices related to lean operation include an electric throttle, a fuel injection valve, an EGR valve, a fuel pump, a lean NOx catalyst, and the like. When the lean NOx catalyst is deteriorated, in order to keep the NOx emission amount within a predetermined value, the carbon dioxide emission amount is increased by frequent occurrence of rich spike (purification processing of stored NOx) and shortening of the lean operation. Therefore, the lean NOx catalyst is also cited as a device related to lean operation performance.

  A thirteenth aspect of the engine control device according to the present invention comprises means for setting a control parameter of the engine based on the directly or indirectly detected greenhouse gas emission amount (see FIG. 7).

  In other words, when greenhouse gas emissions change due to engine differences (individual differences), changes over time, and environmental changes, not only the detection but also the control of the engine increases greenhouse gas emissions. It suppresses.

  According to a fourteenth aspect of the engine control apparatus of the present invention, the means for setting the engine control parameter in the third aspect includes means for setting the target air-fuel ratio of the engine.

  That is, a means for setting the operating air-fuel ratio of the engine is provided as the best operating state of the engine correlated with the carbon dioxide concentration.

  According to a fifteenth aspect of the engine control apparatus of the present invention, there is provided means for informing the outside of the directly or indirectly detected greenhouse gas emission amount or information based on the greenhouse gas emission amount ( (See FIG. 8).

  In other words, if it is possible to solve the problem in the engine system, it responds, but if it is not possible, it notifies the driver or the like and prompts them to take a predetermined measure. Alternatively, by outputting the greenhouse gas emissions of each engine to the outside, for example, centralized processing is performed, and the total amount of greenhouse gases emitted from automobiles existing in a predetermined area is calculated more accurately. .

  On the other hand, an automobile according to the present invention is characterized by mounting an engine to which the control device according to any one of the first to fifteenth aspects is applied.

  In this case, the control means preferably includes means for directly or indirectly detecting the travel distance of the automobile and means for calculating the greenhouse gas emission amount at a predetermined travel distance.

  That is, the amount of greenhouse gas emission per predetermined travel distance is calculated to obtain the greenhouse gas emission performance of the engine or the automobile.

  According to the present invention, since the amount of greenhouse gas discharged from the engine is detected directly or indirectly online, the difference in performance due to engine differences (individual differences), changes over time, etc. This makes it possible to effectively reduce greenhouse gas emissions.

  Embodiments of the present invention will be described below with reference to the drawings.

[First Embodiment]
FIG. 9 is a schematic configuration diagram showing a first embodiment of a control device according to the present invention together with an example of an in-vehicle engine to which the control device is applied.

  The illustrated engine 10 is, for example, a multi-cylinder engine having four cylinders, and is slidably fitted into the cylinder 12 and the cylinders # 1, # 2, # 3, and # 4 of the cylinder 12. And a combustion chamber 17 is defined above the piston 15. A spark plug 35 is provided in the combustion chamber 17.

  Air used for combustion of fuel is taken in from an air cleaner 21 provided at the start end of the intake passage 20, passes through an air flow sensor 24, passes through an electric throttle valve 25, enters a collector 27, and passes through the collector 27. The air is sucked into the combustion chambers 17 of the cylinders # 1, # 2, # 3, and # 4 via the intake valve 28 disposed at the downstream end (intake port) of the intake passage 20. In addition, a fuel injection valve 30 is provided in the combustion chamber 17.

  The mixture of the air sucked into the combustion chamber 17 and the fuel injected from the fuel injection valve 30 is ignited by the spark plug 35 and explosively burned, and the combustion waste gas (exhaust gas) is exhausted from the combustion chamber 17. The exhaust gas is discharged to the individual passage portion 40A forming the upstream portion of the exhaust passage 40 via the valve 48, and flows into the lean NOx catalyst 50 disposed in the exhaust passage 40 through the exhaust passage portion 40B from the individual passage portion 40A. After being purified, it is discharged outside. During the lean operation, the lean NOx catalyst 50 has a function of storing NOx discharged from the engine (combustion chamber 17) and desorbing and purifying the stored NOx by performing a rich operation.

Further, an O ₂ sensor 51 is disposed on the exhaust passage 40 downstream of the lean NOx catalyst 50, and an A / F sensor 52 is disposed on the exhaust passage 40 near the exhaust collecting portion 40 B upstream of the catalyst 50. ing.

The A / F sensor 52 has a linear output characteristic with respect to the concentration of oxygen contained in the exhaust gas. The relationship between the oxygen concentration in the exhaust gas and the air-fuel ratio is substantially linear. Therefore, the A / F sensor 52 that detects the oxygen concentration can determine the air-fuel ratio in the exhaust gas collecting section 40B. Further, from the signal from the O ₂ sensor 51, it can be determined whether the oxygen concentration or stoichiometry downstream of the lean NOx catalyst 50 is rich or lean.

  Further, a part of the exhaust gas discharged from the combustion chamber 17 to the exhaust passage 40 is introduced into the intake passage 20 through the EGR passage 41 as necessary, and is supplied to each cylinder through the branch passage portion of the intake passage 20. It returns to the combustion chamber 17. The EGR passage 41 is provided with an EGR valve 42 for adjusting the EGR rate.

  And in the control apparatus 1 of this embodiment, in order to perform various control of the engine 10, the control unit 100 incorporating a microcomputer is provided.

  The control unit 100 basically includes a CPU 101, an input circuit 102, an input / output port 103, a RAM 104, a ROM 105, and the like as shown in FIG.

The control unit 100 obtains, as an input signal, a signal corresponding to the intake air amount detected by the air flow sensor 24, a signal corresponding to the opening of the throttle valve 25 detected by the throttle sensor 34, and a crank angle sensor 37. A signal representing the rotation (engine speed) and phase of the crankshaft 18, a signal corresponding to the oxygen concentration in the exhaust gas detected by the O ₂ sensor 51 disposed downstream of the catalyst 50 in the exhaust passage 40, and exhaust gas A signal corresponding to the oxygen concentration (air-fuel ratio) detected by the A / F sensor 52 disposed in the exhaust collecting portion 40B upstream of the catalyst 50 in the passage 40, and detected by the water temperature sensor 19 disposed in the cylinder 12. A signal corresponding to the engine coolant temperature to be depressed, depression of the accelerator pedal 39 obtained from the accelerator sensor 36 A signal corresponding to the amount (indicating the torque required by the driver), a signal corresponding to the vehicle speed of the automobile on which the engine 10 is mounted, obtained from the vehicle speed sensor 29, and the like are supplied.

In the control unit 100, outputs of sensors such as the A / F sensor 52, the O ₂ sensor 51, the throttle sensor 34, the air flow sensor 24, the crank angle sensor 37, the water temperature sensor 16, and the accelerator sensor 36 are input. After signal processing such as noise removal is performed in the circuit 102, the signal is sent to the input / output port 103. The value of the input port is stored in the RAM 104 and processed in the CPU 101. A control program describing the contents of the arithmetic processing is written in the ROM 105 in advance. A value representing each actuator operation amount calculated according to the control program is stored in the RAM 104 and then sent to the output port 103.

  The operation signal for the spark plug 35 is set to an ON / OFF signal that is ON when the primary coil in the ignition output circuit 116 is energized and is OFF when the primary coil is not energized. The ignition timing is the time when the ignition timing changes from ON to OFF. The signal for the spark plug 35 set in the output port 103 is amplified to a sufficient energy necessary for ignition by the ignition output circuit 116 and supplied to the spark plug 35. Further, an ON / OFF signal that is ON when the valve is opened and OFF when the valve is closed is set as a drive signal (air-fuel ratio control signal) of the fuel injector 30, and the fuel injector 30 opens the fuel injector 30. Is amplified to a sufficient energy to be supplied to the fuel injection valve 30. A drive signal for realizing the target opening degree of the electric throttle valve 25 is sent to the electric throttle valve 30 through the electric throttle valve drive circuit 118.

The control unit 100 calculates the air-fuel ratio upstream of the lean NOx catalyst 50 from the signal of the A / F sensor 52, and determines whether the oxygen concentration or stoichiometry downstream of the catalyst 50 is rich or lean from the signal of the O ₂ sensor 51. calculate. Further, feedback control for sequentially correcting the fuel injection amount or the intake air amount is performed using the outputs of the sensors 51 and 52 so that the purification efficiency of the catalyst 50 is optimized.

  Next, the processing contents when the control unit 100 directly or indirectly detects the emission amount of carbon dioxide, which is a greenhouse gas, will be specifically described.

  FIG. 11 is a functional block diagram showing a control system by the control unit 100 and is a main part of the air-preceding type torque base control. This control system includes a target torque calculation unit 210, a target air amount calculation unit 220, a target throttle opening calculation unit 230, an ETC (electrically controlled throttle valve) control unit 240, a target air-fuel ratio calculation unit 250, and an actual air amount calculation unit 260. , Fuel injection amount calculation means 270 and carbon dioxide emission amount calculation means 300.

  First, the target torque is calculated from the accelerator opening by the target torque calculating means 210. Next, the target air amount is calculated from the target torque and the target air-fuel ratio, the target throttle opening for realizing the target air amount is calculated, and the throttle opening is calculated based on the output of the opening sensor 34 by the ETC control means 240. F / B control. The fuel injection amount is calculated from the actual air amount detected by the airflow sensor 24 and the target air-fuel ratio. Note that only the carbon dioxide emission calculation means 300 is related to the present invention, and other calculation means specifications are already known and there are many materials, so the details are omitted here. Hereinafter, the details of the carbon dioxide emission calculation means 300 will be described.

<Carbon dioxide (CO ₂ ) emission calculation means 300>
The calculation means 300 calculates the amount of carbon dioxide (engine out) discharged from the combustion chamber 17 of the engine 10 per unit travel distance. Specifically, as shown in FIG. 12, the engine air-fuel ratio, target EGR ratio, the target engine torque, the engine-out CO ₂ concentration calculating means 310 for receiving the engine speed, and calculates an engine-out CO ₂ concentration The exhaust gas flow rate (volume flow rate) is obtained from the intake air amount (mass flow rate) obtained from the airflow sensor 24, and the CO ₂ emission amount (volume flow rate) is obtained by multiplying the engine CO ₂ concentration. The CO ₂ emission amount (mass flow rate) is converted into the CO ₂ emission amount (mass flow rate), and the output of the vehicle speed sensor 29 is divided by the travel distance obtained by integration to obtain the CO ₂ emission amount (mass per unit travel distance). )

  For example, about 10 ms is conceivable for this processing, but the calculation cycle may be optimized according to the target accuracy.

<Engine Out CO ₂ Concentration Calculation Unit 310>
In the present calculation means 310, the concentration of carbon dioxide (engine out) discharged from the combustion chamber 17 of the engine 10 is calculated. Specifically, as shown in FIG. 13, the basic value of CO ₂ concentration is calculated from the air-fuel ratio of the engine-out (exhaust gas discharged from the combustion chamber 17), which is the output of the A / F sensor 52, and the target EGR rate. Then, the CO ₂ concentration correction value is calculated from the target engine torque and the engine speed, and is multiplied to obtain the engine out CO ₂ concentration. The map used for the calculation of the CO ₂ concentration basic value and the CO ₂ concentration correction value may be determined in advance from the test results of the target engine. Here, although the calculation method of the target EGR rate is not specified, for example, the target EGR rate may be calculated from the target torque, the target rotation speed, or the like.

As described above, in the present embodiment, the amount of carbon dioxide exhausted from the combustion chamber 17 is determined based on the carbon dioxide concentration obtained by the engine-out CO ₂ concentration calculating means 310 and the intake air amount (mass flow rate) obtained from the airflow sensor 24. ) Is indirectly detected (estimated) from the exhaust gas flow rate (volumetric flow rate) calculated based on the engine exhaust gas flow rate).

[Second Embodiment]
In the second embodiment, the carbon dioxide emission amount of the tail pipe 40C (the downstream portion of the catalyst 50 in the exhaust passage 40) is indirectly detected.

  9, 10, and 11 referred to in the first embodiment are the same as those in the present embodiment, and thus a duplicate description is omitted. The details of the carbon dioxide emission calculating means 400 having a configuration different from that of the first embodiment (300) will be described below.

<Carbon dioxide (CO ₂ ) emission calculation means 400>
In the calculation means 400, the amount of carbon dioxide discharged from the tail pipe 40B constituting the downstream portion of the catalyst 50 in the exhaust passage 40 is calculated per unit travel distance. Specifically, as shown in FIG. 14, the engine air-fuel ratio, target EGR ratio, the target engine torque, the engine-out CO ₂ concentration calculating means 410 for receiving the engine speed, and calculates an engine-out CO ₂ concentration . The engine air-fuel ratio, the target EGR rate, the catalyst produced CO ₂ concentration calculating means 420 for receiving the catalyst temperature, HC generated in the catalyst 50, calculating a catalyst product CO ₂ concentration produced by the oxidation reaction of CO, etc. To do. The catalyst-generated CO ₂ concentration is added to the engine-out CO ₂ concentration to obtain the tail pipe CO ₂ concentration. The exhaust gas flow rate (volume flow rate) is obtained from the intake air amount (mass flow rate) obtained from the airflow sensor 24, and the CO ₂ emission amount (volume flow rate) is obtained by multiplying the tail pipe CO ₂ concentration. The CO ₂ emission amount (mass flow rate) is converted into the CO ₂ emission amount (mass flow rate), and the output of the vehicle speed sensor 29 is divided by the travel distance obtained by integration to obtain the CO ₂ emission amount (mass per unit travel distance). )

  For example, about 10 ms is conceivable for this processing, but the calculation cycle may be optimized according to the target accuracy.

<Engine Out CO ₂ Concentration Calculation Unit 410>
In the present calculation means 410, the concentration of carbon dioxide exhausted from the combustion chamber 17 of the engine 10 (engine out) is calculated. Specifically, since it is the same as that (310) shown in FIG.

<Catalyst Generation CO ₂ Concentration Calculation Unit 420>
In the present calculation means 420, the concentration of carbon dioxide produced by the catalyst 50 is calculated. Specifically, as shown in FIG. 15, the basic value of CO ₂ concentration is calculated from the air-fuel ratio of the engine-out (exhaust gas discharged from the combustion chamber 17) that is the output of the A / F sensor 52 and the target EGR rate. Calculate, calculate the CO ₂ concentration correction value from the catalyst temperature, and multiply both to obtain the catalyst-generated CO ₂ concentration. The map used for the calculation of the CO ₂ concentration basic value and the CO ₂ concentration correction value may be determined in advance from the test results of the target catalyst.

[Third Embodiment]
In the third embodiment, the carbon dioxide emission amount of the tail pipe 40C (downstream of the catalyst) is directly detected.

9, 10, and 11 referred to in the first and second embodiments described above are the same as those in the present embodiment, and thus redundant description is omitted. However, in the first and second embodiments, a CO ₂ sensor 53 is used in this embodiment instead of the O ₂ sensor 51 disposed downstream of the catalyst 50 in the exhaust passage 40. Hereinafter, the details of the carbon dioxide emission calculating means 500 having a configuration different from that of the first and second embodiments (300, 400) will be described. Details of the carbon dioxide emission calculating means will be described below.

<Carbon dioxide (CO ₂ ) emission calculation means 500>
The calculation unit 500 calculates the amount of carbon dioxide discharged from the tail pipe 40C (downstream of the catalyst) per unit travel distance. Specifically, as shown in FIG. 16, the output of the CO ₂ sensor 53 downstream of the catalyst 50 is set as the tail pipe CO ₂ concentration. The exhaust gas flow rate (volume flow rate) is obtained from the intake air amount (mass flow rate) obtained from the airflow sensor 24, and the CO ₂ emission amount (volume flow rate) is obtained by multiplying the tail pipe CO ₂ concentration. The CO ₂ emission amount (mass flow rate) is converted into the CO ₂ emission amount (mass flow rate), and the output of the vehicle speed sensor 29 is divided by the travel distance obtained by integration to obtain the CO ₂ emission amount (mass per unit travel distance). )

  For example, about 10 ms is conceivable for this processing, but the calculation cycle may be optimized according to the target accuracy.

[Fourth Embodiment]
In the fourth embodiment, the carbon dioxide emission amount in the tail pipe 40C (catalyst downstream) is indirectly detected based on the deterioration diagnosis of the lean NOx catalyst 50.

In the present embodiment, the performance diagnosis of the lean NOx catalyst 50 is performed online, and the rich spike timing is set so that the NOx emission amount (unstored amount) during lean operation becomes a predetermined value according to the performance of the catalyst 50. Be controlled. When the catalyst 50 deteriorates, the NOx storage performance at the time of lean decreases, so that the rich spike frequency increases in order to keep the unstored NOx amount at a predetermined value. Along with this, the carbon dioxide emission amount calculated by the carbon dioxide emission amount calculating means also increases, and when the carbon dioxide emission amount becomes a predetermined value or more (when the catalyst deteriorates to a predetermined level), as a CO ₂ emission abnormality, This is a notification to the outside.

Since FIGS. 9 and 10 referred to in the first and second embodiments are the same as those in the present embodiment, redundant description is omitted. However, FIG. 17 is a functional block diagram showing a control system by the control unit 100 corresponding to FIG. 11 referred to in the first, second, and third embodiments, and is a main part of the air-preceding type torque base control. . This control system includes a target torque calculation unit 210, a target air amount calculation unit 220, a target throttle opening calculation unit 230, an ETC (electrically controlled throttle valve) control unit 240, a target air-fuel ratio calculation unit 250, and an actual air amount calculation unit 260. In addition to the fuel injection amount calculation means 270 and the carbon dioxide emission amount calculation means 600 (substantially the same configuration as that of the second embodiment 400), a lean NOx catalyst diagnosis means 710 and a CO ₂ emission amount abnormality determination means 720 are added. Has been. Since other than that is the same, it is not explained in full detail. Further, since there are many known examples of the diagnosis method for the lean NOx catalyst and the on-line control optimization method in the patent literature, the non-patent literature, etc., it will not be described in detail here, but FIG. 18 shows the diagnosis of the lean NOx catalyst. FIG. 19 and FIG. 20 show an example of the target air-fuel ratio calculating means.

Hereinafter, the details of the carbon dioxide emission calculating means 600 and the CO ₂ emission abnormality determining means 720 will be described.

<Carbon dioxide (CO ₂ ) emission calculation means 600>
The calculation means 600 calculates the amount of carbon dioxide discharged from the tail pipe 40C (downstream of the catalyst) per unit travel distance. Specifically, since it has the same configuration as that of the second embodiment (400) shown in FIG. 14, it will not be described in detail here.

<CO ₂ emission abnormality determination means 720>
In this determination means 720, the abnormality determination of the CO ₂ emission amount is performed. Specifically, as shown in FIG. 21, when the CO ₂ emission amount (mass) per unit mileage calculated by the carbon dioxide (CO ₂ ) emission amount calculation means is a predetermined value or more, the notification flag is set as described above. It is to turn on.

In this embodiment, when the CO ₂ emission amount exceeds a predetermined value, the system is notified to the outside. However, the absolute value of the CO ₂ emission amount itself may be notified to the outside (driver, centralized management system, etc.). Good.

  Further, as described above, an engine control parameter, for example, a target air-fuel ratio, may be set based on the carbon dioxide emission detected directly or indirectly. Thereby, the amount of carbon dioxide emissions can be more effectively suppressed.

The figure which is provided for description of the 1st aspect of the control apparatus which concerns on this invention. The figure which is provided for description of the 2nd aspect of the control apparatus which concerns on this invention. The figure which is provided for description of the 3rd aspect of the control apparatus which concerns on this invention. The figure which is provided for description of the 4th aspect of the control apparatus which concerns on this invention. The figure which is provided for description of the 7th aspect of the control apparatus which concerns on this invention. The figure which is provided for description of the 8th aspect of the control apparatus which concerns on this invention. The figure which is provided for description of the 13th aspect of the control apparatus which concerns on this invention. The figure which is provided for description of the 15th aspect of the control apparatus which concerns on this invention. BRIEF DESCRIPTION OF THE DRAWINGS The schematic block diagram which shows 1st Embodiment of the control apparatus which concerns on this invention with the engine to which it is applied. The internal block diagram of the control unit in 1st Embodiment. The control system figure of 1st Embodiment. The figure which is provided for description of the carbon dioxide emission calculating means in the first embodiment. The figure which is provided for description of the engine out CO ₂ concentration calculation means in the first embodiment. The figure which is provided for description of the carbon dioxide emission calculating means in the second embodiment. It is a diagram illustrating the catalyst product CO ₂ concentration calculation means in the second embodiment. The figure which is provided for description of the carbon dioxide emission calculating means in the third embodiment. The control system figure of 4th Embodiment. The figure which is provided for description of the lean NOx catalyst diagnostic means of the fourth embodiment. The figure which is provided for description of the target air-fuel ratio calculating means of the fourth embodiment. The figure which is provided for description of the lean NOx catalyst model of the fourth embodiment. The figure which is provided for description of the CO ₂ emission amount abnormality determination means of the fourth embodiment.

Explanation of symbols

10 Engine 17 Combustion chamber 19 Water temperature sensor 20 Intake passage 21 Air cleaner 24 Air flow sensor 25 Electric throttle valve 27 Collector 28 Throttle opening sensor 29 Vehicle speed sensor 30 Fuel injection valve 34 Throttle opening sensor 35 Spark plug 37 Crank angle (engine speed) ) Sensor 39 Accelerator opening sensor 40 Exhaust passage 40B Exhaust collecting part 40C Tail pipe 50 Lean NOx catalyst 51 Oxygen sensor 52 A / F sensor 100 Control unit 300 Carbon dioxide (CO ₂ ) emission calculation means (first embodiment)
310 engine out CO ₂ concentration calculation means 400 carbon dioxide (CO ₂ ) emission amount calculation means (second embodiment)
410 engine out CO ₂ concentration calculating means 500 carbon dioxide (CO ₂ ) emission calculating means (third embodiment)
600 Carbon dioxide (CO ₂ ) emission calculation means (fourth embodiment)
710 Lean NOx catalyst diagnosis means 720 CO ₂ emission abnormality determination means

Claims (16)

Greenhouse gas emission detection means for directly or indirectly detecting the amount of greenhouse gas emitted from the engine, and diagnosis for individually diagnosing deterioration of individual engine devices related to the greenhouse gas emission An engine control device comprising:
The engine control apparatus according to claim 1, wherein the greenhouse gas emission detection means indirectly detects the greenhouse gas emission based on a diagnosis result of the diagnosis means . The engine control apparatus according to claim 1 , wherein the greenhouse gas emission detection means detects the amount of carbon dioxide emitted from the engine directly or indirectly. The greenhouse gas emission detection means includes a carbon dioxide concentration detection means for directly or indirectly detecting the concentration of carbon dioxide discharged from the combustion chamber of the engine and / or downstream of the catalyst, a combustion chamber of the engine, and 3. An engine control device according to claim 2 , further comprising exhaust gas flow rate detection means for directly or indirectly detecting the exhaust gas flow rate discharged from the downstream of the catalyst. The engine control according to claim 3 , wherein the exhaust gas flow rate detection unit directly or indirectly detects an exhaust gas flow rate per unit time discharged from a combustion chamber of the engine and / or a catalyst downstream. apparatus. The carbon dioxide concentration detection means, the engine according to claim 3 or 4 wherein comprising a carbon dioxide sensor Zaisa distribution in an exhaust passage of the engine, and detecting a direct carbon dioxide concentration by the sensor Control device. The engine control device according to claim 3 or 4 , wherein the carbon dioxide concentration detection means indirectly detects the carbon dioxide concentration based on an operating state of the engine. The carbon dioxide concentration detecting means includes a means for directly or indirectly detecting the carbon dioxide concentration discharged from the combustion chamber of the engine, and a concentration of carbon dioxide newly generated by the catalyst, directly or indirectly. The engine control apparatus according to any one of claims 3 to 6 , further comprising a detecting unit. The engine control device according to claim 6 , wherein at least one of the operating states of the engine is an operating air-fuel ratio of the engine. The carbon dioxide concentration detecting means indirectly detects the carbon dioxide concentration newly generated by the catalyst based on the catalyst inlet or the air-fuel ratio inside the catalyst detected directly or indirectly. The engine control device according to claim 7 . The carbon dioxide concentration detection means, according to claim 7, characterized in that on the basis of the directly or indirectly detected catalyst temperature is indirectly detected carbon dioxide concentration that is newly generated in the catalyst Engine control device. The diagnosis means diagnoses at least one state or performance of an electric throttle valve, a fuel injection valve, an EGR valve, a fuel pump, and a lean NOx catalyst as the engine device. The engine control device according to claim 1 . On the basis of the directly or indirectly detected greenhouse gas emissions, according to any one of claims 1 to 11, characterized in that it comprises a means for setting a control parameter of the engine Engine control device. 13. The engine control device according to claim 12 , wherein the means for setting the engine control parameter comprises means for setting a target air-fuel ratio of the engine. Information based on the directly or indirectly detected greenhouse gas emissions or temperature greenhouse gas emissions, any of claims 1 to 13, characterized in that it comprises a means for informing the outside The engine control device according to one item. An automobile equipped with an engine to which the control device according to any one of claims 1 to 14 is applied. The said control means is provided with the means to detect the driving | running | working distance of a motor vehicle directly or indirectly, and the means to calculate the greenhouse gas emission amount in a predetermined | prescribed driving | running | working distance, The Claim 15 characterized by the above-mentioned. Car.

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