JP4196836B2 - Automatic adapting device - Google Patents

Description

  The present invention relates to an automatic adaptation device.

  When a newer internal combustion engine is developed than before, an operation for searching for the value of an engine operation control parameter capable of obtaining an optimal engine output value, that is, an adaptation operation is performed. In this adaptation work, the optimal engine output value, for example, the optimal exhaust emission amount, is obtained over a long period of time by gradually changing the values of parameters such as the fuel injection amount and fuel injection timing based on experience. Possible values for parameters that can be searched are searched. The same is true when developing a new vehicle.

  However, even if searching for parameter adaptation values based on experience in this way, it becomes difficult to find the optimum parameter adaptation values as the number of parameters increases, and it takes a long time to find parameter adaptation values. Therefore, there is a problem that not only development takes time but also a great deal of labor is required.

Therefore, an automatic adaptation device that automatically performs parameter adaptation has been proposed (see, for example, Patent Document 1). In such an automatic adaptation device, an analyzer that extracts exhaust gas from an engine exhaust passage and analyzes the exhaust gas component is usually used, and parameters are set so that the exhaust gas component detected by the analyzer becomes an optimum value. Is automatically adapted.
JP 2002-138889 A

  However, for example, if the engine misfires and a large amount of unburned HC is discharged due to inappropriate parameter operation during automatic calibration, a large amount of unburned HC is deposited in the exhaust gas extraction passage of the analyzer. The accuracy of the analyzer deteriorates, and in some cases, the analysis becomes impossible and the automatic adaptation function must be stopped. However, unattended automatic adaptation is extremely difficult if the automatic adaptation operation must be stopped during automatic adaptation as described above, and this is a serious problem.

  In order to solve the above problems, according to the present invention, a plurality of engine operation control parameters are set in a predetermined operation direction in accordance with a predetermined operation sequence so that the output value satisfies a predetermined target value. In an automatic adapting device that automatically adjusts parameters by sequentially operating, it is equipped with an analyzer for extracting exhaust gas from the engine exhaust passage and analyzing the exhaust gas components. When it is determined that the emission component of exhaust gas that may be deposited and deposited exceeds a predetermined value, the operation of the parameters according to the predetermined operation sequence and the predetermined operation direction is temporarily stopped. Like to do.

  It can suppress that the analysis precision of an analyzer falls.

  FIG. 1 shows an entire automatic adaptation apparatus for automatically adapting parameters for operation control of a compression ignition type internal combustion engine. In this case, the internal combustion engine may be a spark ignition type internal combustion engine.

  Referring to FIG. 1, 1 is an engine body, 2 is an electrically controlled fuel injection valve for injecting fuel into the combustion chamber of each cylinder 3, 4 is an intake manifold, 5 is an exhaust manifold, and 6 is an exhaust turbocharger. Respectively. The intake manifold 4 is connected to the outlet portion of the intake compressor 6 a of the exhaust turbocharger 6, and the inlet portion of the intake compressor 6 a is connected to the air cleaner 8 via the intake duct 7. An intake throttle valve 10 driven by an actuator 9 such as a step motor is disposed in the intake duct 7.

  On the other hand, the exhaust manifold 5 is connected to the inlet portion of the exhaust turbine 6 b of the exhaust turbocharger 6, and the outlet portion of the exhaust turbine 6 b is connected to the exhaust pipe 12. The intake manifold 4 and the exhaust manifold 5 are connected to each other through an exhaust gas recirculation (hereinafter referred to as EGR) passage 13, and an EGR control valve 15 driven by an actuator 14 such as a step motor in the EGR passage 13. Is arranged.

  On the other hand, the fuel injection valve 2 is connected to a common rail 17 through a fuel supply pipe 16. Fuel is supplied into the common rail 17 from an electrically controlled fuel pump 18 with variable discharge amount, and the fuel supplied into the common rail 17 is supplied to the fuel injection valve 2 via each fuel supply pipe 16. A fuel pressure sensor 19 for detecting the fuel pressure in the common rail 17 is attached to the common rail 17, and a fuel pump 18 is configured so that the fuel pressure in the common rail 17 becomes a target fuel pressure based on an output signal of the fuel pressure sensor 19. The discharge amount is controlled.

  An electronic control unit 20 for controlling the operation of the internal combustion engine is composed of a digital computer, and a ROM (read only memory) 22, a RAM (random access memory) 23, and a CPU (microprocessor) connected to each other by a bidirectional bus 21. 24, and an input / output port 25. A combustion pressure sensor 31 is attached to each cylinder 3, and output signals of various sensors such as the combustion pressure sensor 31 are input to the input / output port 25 via corresponding AD converters 26. A load sensor 29 that generates an output voltage proportional to the amount of depression of the accelerator pedal 28 is connected to the accelerator pedal 28, and an output signal of the load sensor 29 is connected to the input / output port 25 via a corresponding AD converter 26. Entered. The crank angle sensor 30 generates an output pulse every time the engine rotates by a crank angle of 15 °, for example, and this output pulse is input to the input / output port 25. On the other hand, the input / output port 25 is connected to the fuel injection valve 2, the throttle valve actuator 9, the EGR control valve actuator 14, and the fuel pump 18 through corresponding drive circuits 27.

As shown in FIG. 1, an electronic control unit 40 is provided for performing an adaptation action, and an output shaft of the internal combustion engine is connected to a dynamometer 41. This dynamometer 41 is connected to the electronic control unit 40 and is controlled by the electronic control unit 40. Also, an analyzer 42 for analyzing exhaust gas components such as NO _x amount, smoke concentration, particulate amount, HC amount, CO amount in exhaust gas, fuel consumption meter 43 of fuel consumed by the internal combustion engine, and internal combustion engine A sound level meter 44 for detecting combustion noise generated by the noise is provided, and output signals from the analyzer 42, the fuel consumption level meter 42, and the noise level meter 44 are input to the electronic control unit 40. The electronic control unit 40 and the input / output port 25 of the electronic control unit 20 are connected to each other via a bidirectional bus 45.

  The analyzer 42 includes an exhaust gas extraction pipe 46 inserted into the exhaust pipe 12 for extracting the exhaust gas, and the exhaust gas is detected by a detection unit 47 via an exhaust gas extraction path in the exhaust gas extraction pipe 46. Is sent to. An air pump 49 is connected to the exhaust gas extraction path via an on-off valve 48. When the exhaust gas extraction path is to be cleaned, air is sent from the air pump 49 into the exhaust gas extraction path. Further, a reference gas supply device 51 is connected to the exhaust gas extraction path via an on-off valve 50, and the reference gas is sent from the reference gas supply device 51 to the detection unit 47 when the analyzer 42 should be calibrated. It should be noted that the internal configuration of the analyzer 42 shown in FIG. 1 is illustrated for the sake of explanation, and does not depict the actual internal configuration.

First, the automatic adaptation method employed in the present invention will be schematically described.
In the present invention, basically, a plurality of engine operation control parameters are sequentially operated in a predetermined operation direction according to a predetermined operation sequence so that the output value satisfies a predetermined conformity target value. It is adapted automatically.

Here, in the embodiment according to the present invention, all or all of the main injection timing, the pilot injection timing, the pilot injection amount, the common rail pressure, the opening degree of the EGR control valve, the opening degree of the intake throttle valve are used as the parameters for engine operation control. Some have been adopted. Further, in the embodiment according to the present invention, the output values are all of emission, combustion noise, and fuel consumption or a part of them, and the emissions include NO _x amount, smoke concentration or particulate amount in the exhaust gas. All of HC amount and CO amount or a part of them is employed.

On the other hand, regarding the target value for adaptation, in the embodiment according to the present invention, among these output values, the target values for NO _x amount, particulate amount, HC amount, CO amount, and fuel consumption are traveled in the travel mode for evaluating emissions. The total output target value, which is the integrated value at the time, is set, and the remaining output values, that is, the target values for combustion noise and smoke concentration are set as target values in the respective operating states. _The amount of NO _x out of the thus output value, the particulate amount, HC amount, CO quantity, in the embodiment according to the total amount target value is an integrated value is While the present invention when adapted target value of fuel consumption, which travels at a mode A suitable target value in each conforming operation state of these output values so that this total amount target value falls within the allowable range is obtained, and the conforming target value in each conforming operation state has the total amount target value of NO _x amount and particulates. The amount, HC amount, CO amount, and fuel consumption are also set as target values.

  Note that each operating state to be adapted is determined as a point on the map shown in FIG. 2 (black circle in FIG. 2). Therefore, each operating state to be adapted is determined from the engine speed N and the fuel injection amount Q. It becomes. In this case, a map having the engine speed N on the horizontal axis and the output torque on the vertical axis can be used as the map.

  When performing automatic adjustment of parameters, first, the operation order and operation direction of a plurality of parameters for reducing the output value exceeding the adjustment target value were determined, and these parameters were determined according to the determined operation order. The parameters are adapted by sequentially operating in the operation direction. As described above, the operation order of the parameters to be operated when the output value exceeds the conformity target value and the relationship between the operation direction and the output value are stored in advance as shown in FIG. 3 and FIG. When the conformity target value is exceeded, the parameter operation order and operation direction are determined based on the relationship shown in FIGS.

First, FIG. 3 will be described. In FIG. 3, the smoke concentration, NO _x , HC, and combustion noise are output values, and the main injection timing, the pilot injection interval indicating the interval between the main injection and the pilot injection, the pilot injection amount, An example in which the common rail pressure and EGR control valve are used as parameters for engine operation control is shown. FIG. 3 shows a case where one of the output values exceeds the conforming target value, and the output value exceeding the conforming target value is indicated by numeral 1 in the column indicating the output value. For example, in FIG. 1 shows the case where the smoke concentration exceeds the conformity target value.

  On the other hand, the numbers surrounded by circles in the parameter column indicate the parameter operation order. For example, in FIG. 1, the operation order is an EGR control valve, main injection timing, common rail pressure, pilot injection interval, and pilot injection amount. This operation order is an order that is considered to have a great influence on the reduction of the corresponding output value (smoke density in No. 1) from experience.

  The characters in the parameter column indicate the operation direction of the parameter. For example, no. The EGR control valve in 1 indicates that the operation direction is a direction in which the EGR control valve is closed. In addition, when two characters are present in the parameter column, there are cases where it is not known which operation direction affects the reduction of the output value, or cases where the operation direction differs depending on the injection timing. For example, no. The main injection timing in 1 is a case where it is not known whether to retard or advance the injection timing in order to reduce the smoke concentration. No. 3 indicates that the main injection timing should be retarded if the injection timing is BTDC (before compression top dead center) and advanced if it is ATDC (after compression top dead center).

4 also uses the smoke concentration, NO _x , HC, and combustion noise as output values as in FIG. 3, and the main injection timing, the pilot injection interval indicating the interval between the main injection and the pilot injection, the pilot injection amount, the common rail pressure, and the EGR control. The example which made the valve the parameter for engine operation control is shown. FIG. 4 shows a relationship between a plurality of output values that exceed the conformity target value when a plurality of output values exceed the conformance target value, and the operation sequence and operation direction of the parameter to be operated. The operation order and operation direction of parameters are changed according to the order of deterioration of output values.

The order of this deterioration is indicated by numerals 1 and 2 in the column indicating the output value. For example, in FIG. 1 indicates that the smoke concentration and the NO _x amount exceed the conforming target values, and at this time, the degree of excess of the smoke concentration is greater than the degree of excess of the NO _x amount. Therefore, in this case, the smoke concentration is in the deterioration order 1 and NO _x is in the deterioration order 2.

  On the other hand, in FIG. 4, as in FIG. 3, the numbers in circles in the parameter column indicate the parameter operation order, and the characters in the parameter column indicate the parameter operation direction. In the parameter column, a blank field means that the corresponding parameter is not operated.

In the embodiment according to the present invention, the parameters are sequentially operated in the operation order and the operation direction of the parameters determined from the relationship shown in FIG. 3 or FIG. For example, as a result of operation using a certain parameter, it is assumed that the amount of NO _x greatly exceeds the target value for adaptation and the combustion noise slightly exceeds the target value for adaptation, that is, No. 1 in FIG. If the main injection timing is BTDC at this time, the main injection timing is retarded by a predetermined crank angle.

  By the way, when parameters are manipulated according to the relationship shown in FIG. 3 or FIG. 4 during automatic adaptation, emission components of exhaust gas that may be deposited on the exhaust gas extraction path of the analyzer 42, such as unburned HC, If it increases greatly, a large amount of unburned HC deposits and accumulates in the exhaust gas extraction passage of the analyzer 42. If the parameter operation is continued in such a case, the analysis accuracy of the analyzer 42 is lowered and automatically adapted. Cannot be performed.

  Therefore, in the present invention, when it is determined that the emission component of exhaust gas that may be deposited on the exhaust gas extraction path of the analyzer 42 exceeds a predetermined value, a predetermined operation sequence and a predetermined value are determined. The parameter operation according to the operation direction is temporarily stopped. Thus, by temporarily stopping the parameter operation, it is possible to suppress a decrease in accuracy of the analyzer 42.

  In the embodiment according to the present invention, it is determined that the emission component of the exhaust gas has exceeded the specified value, and the emission component is reduced when the operation of the parameter according to the predetermined operation sequence and the predetermined operation direction is stopped. The parameters are manipulated as follows. Specifically, when it is determined that the emission component of the exhaust gas has exceeded the specified value, and the operation of the parameters according to the predetermined operation sequence and the predetermined operation direction is stopped, the parameter combination and the parameter value are The parameter combination and parameter values used immediately before are determined from the relationship shown in FIG. 3 or FIG.

  The emission component of the exhaust gas that may be deposited on the exhaust gas extraction path of the analyzer 42 is unburned HC or smoke. In the embodiment according to the present invention, this emission component is detected by the analysis device 42, and the analysis device 42 determines whether or not the emission component exceeds a specified value. Alternatively, a misfire detecting means for detecting misfire of the engine, for example, a combustion pressure sensor 31 as shown in FIG. 1, is provided, and when the misfire of the engine is detected by the misfire detecting means, the emission component becomes a specified value. It is judged that it exceeded.

Next, the automatic adaptation method according to the present invention will be described along the automatic adaptation routine shown in FIG.
Referring to FIG. 5, first, in step 100, an initial setting value of each parameter is determined, and an adaptation operation condition setting process for determining an adaptation target value in each adaptation operation state of each output value is executed. Next, at step 101, the engine is operated in one of the operation regions to be adapted using the parameter initial value set at step 100. Next, at step 102, the emission is measured, and at step 103, it is determined whether or not an emission component such as unburned HC has exceeded a specified value. When the emission component such as unburned HC is below the specified value, the routine proceeds to step 104.

  In step 104, it is determined whether or not all the output values satisfy the matching target value. When all the output values do not satisfy the conformance target value, that is, when one or a plurality of output values exceed the conformance target value, the parameters to be operated from the relationship shown in FIG. The operation order and the operation direction are determined, and the engine is operated with the determined parameters. Next, the parameters are sequentially operated according to the relationship shown in FIG. 3 or FIG. 4 until all the output values satisfy the matching target values.

  When it is determined in step 104 that all output values satisfy the adaptation target value, the routine proceeds to step 105, where it is determined whether or not the adaptation operation has been completed for all the adaptive operation states indicated by black circles in FIG. When the conforming operation is not completed for all conforming operation states, the routine proceeds to step 106, and the adapting action in the next conforming operation state is started. When the conforming operation is completed for all conforming operation states, the automatic conforming operation is completed.

  Now, when it is determined in step 103 that the emission component such as unburned HC has exceeded the specified value during the automatic adaptation operation, the routine proceeds to step 107, and the parameter combination and parameter value are determined one time before those determined from FIG. Return to the combination of parameters and parameter values used. Next, at step 108, the exhaust emission is measured, and then at step 109, it is judged if the emission component such as unburned HC has exceeded the previous detection value. That is, whether or not the detected value in the previous parameter combination and parameter value when it is determined in step 103 that the emission component has exceeded the specified value, that is, whether or not the detected value in the same parameter combination and parameter value has been exceeded. Determined.

  When the emission component such as unburned HC is equal to or lower than the previous specified value, the process returns to step 101 and the automatic adaptation action is continued. That is, the parameter operation is performed again according to the relationship shown in FIG. However, once it is determined that the emission component has exceeded the specified value, the combination of parameters used at that time and the use of the parameter values are subsequently prohibited.

  On the other hand, when it is determined in step 109 that the emission component such as unburned HC exceeds the previous specified value, it is considered that unburned HC or the like is deposited in the exhaust gas extraction path of the analyzer 42. At this time, the routine proceeds to step 120 where purge processing is performed. Next, in step 130, high temperature processing is performed, and in step 140, calibration processing is performed. The purge process shown in step 120 is shown in FIG. 6, the high temperature process shown in step 130 is shown in FIG. 7, and the calibration process shown in step 140 is shown in FIG.

  Referring to the purge process shown in FIG. 6, first, in step 121, engine operating conditions suitable for sending air from the air pump 49 into the exhaust gas extraction path, that is, purging are set. This operating condition is a low-load operating state in which the amount of unburned HC and smoke concentration in the exhaust gas is low and the pressure in the exhaust pipe 12 is low. Next, air purge is started in step 122, and purge is terminated when a predetermined purge end condition is satisfied in step 123. When the purge is completed, the routine proceeds to step 124 where exhaust emission is measured.

  Next, at step 125, it is judged if the emission component such as unburned HC exceeds a specified value. When the exhaust gas extraction path is cleaned by purging air and the emission components such as unburned HC become below the specified value, the process proceeds to step 126. When it is determined in step 103 that the emission components exceed the specified value The parameter combination and parameter value used immediately before the parameter combination and parameter value used are returned. Next, returning to step 101 in FIG. 5, the automatic fitting operation is continued again. On the other hand, when it is determined in step 125 that the emission component has exceeded the specified value, the process proceeds to a high temperature process shown in FIG.

  Referring to FIG. 7, first, in step 131, the unburned HC adhering and depositing in the exhaust gas extraction passage is set to an operating condition capable of incineration. This operating condition is, for example, a high-load operating state where the exhaust gas becomes high temperature. Next, at step 132, the exhaust emission is measured so that the hot exhaust gas flows into the exhaust gas extraction path. Next, at step 133, it is judged if a predetermined condition for terminating the high temperature treatment is satisfied. When the high temperature processing termination condition is satisfied, the routine proceeds to step 134.

  In step 134, engine operating conditions suitable for lowering the engine temperature and cleaning the exhaust gas extraction passage of the analyzer 42 with air are set. This engine operating condition is a low load operating state. That is, in step 134, the engine is operated at a low load, and air is sent from the air pump 49 into the exhaust gas extraction path. Next, at step 135, the exhaust emission is measured.

  Next, at step 136, it is judged if an emission component such as unburned HC exceeds a specified value. If the unburned HC accumulated in the exhaust gas extraction passage is incinerated by raising the exhaust gas temperature and the emission components such as unburned HC become below a specified value, the process proceeds to step 137 and the emission component is specified in step 103. The parameter combination and parameter value used immediately before the parameter combination and parameter value used when it is determined that the value has been exceeded are returned to. Next, returning to step 101 in FIG. 5, the automatic fitting operation is continued again. On the other hand, when it is determined in step 136 that the emission component has exceeded the specified value, the process proceeds to the calibration process shown in FIG.

  Referring to FIG. 8, first, in step 141, the calibration operation of the analyzer 42 is performed under a predetermined engine operating state. The calibration operation of the analyzer 42 is executed by sending reference gas from the reference gas supply device 51 to the detection unit 47. When this calibration operation is completed, the routine proceeds to step 142 where exhaust emission is measured.

  Next, at step 143, it is judged if the emission component such as unburned HC exceeds a specified value. If the emission component such as unburned HC becomes a specified value or less by performing the calibration work of the analyzer 42, the process proceeds to step 144, and the parameter used when it is determined in step 103 that the emission component exceeds the specified value. The parameter combination and parameter value used before the combination and parameter value are restored. Next, returning to step 101 in FIG. 5, the automatic fitting operation is continued again. On the other hand, when it is determined in step 143 that the emission component exceeds the specified value, the automatic adaptation operation is stopped.

It is a general view of an automatic adaptation apparatus. It is a figure which shows a map. It is a figure which shows the operation order and operation direction of a parameter. It is a figure which shows the operation order and operation direction of a parameter. It is a flowchart for performing automatic adaptation. It is a flowchart for performing a purge process. It is a flowchart for performing a high temperature process. It is a flowchart for performing a calibration process.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Engine main body 20, 40 ... Electronic control unit 42 ... Analyzer

Claims (13)

  An automatic adaptation device that automatically adjusts parameters by sequentially operating a plurality of engine operation control parameters in a predetermined operation direction according to a predetermined operation sequence so that an output value satisfies a predetermined adjustment target value. The exhaust gas extraction component from the engine exhaust passage to analyze the exhaust gas component, the exhaust gas emission component that may be deposited on the exhaust gas extraction path of the analyzer An automatic adaptation device that temporarily stops the operation of parameters in accordance with the predetermined operation sequence and a predetermined operation direction when it is determined that a predetermined specified value is exceeded.   The automatic adaptation apparatus according to claim 1, wherein the emission component is unburned HC or smoke.   3. The automatic adaptation device according to claim 2, wherein the emission component is detected by an analysis device, and it is determined by the analysis device whether or not the emission component exceeds a specified value.   The automatic adaptation device according to claim 2, further comprising misfire detection means for detecting misfire of the engine, wherein when the misfire of the engine is detected, it is determined that the emission component exceeds a specified value.   The parameter operation according to the predetermined operation order and the predetermined operation direction is stopped when it is determined that the emission component exceeds a specified value, and the parameter is operated so that the emission component is reduced. The automatic adaptation apparatus according to 1.   When it is determined that the emission component has exceeded the specified value, the operation of the parameter according to the predetermined operation sequence and the predetermined operation direction is stopped, and the parameter combination and the parameter value are used one before. 6. The automatic adaptation device according to claim 5, wherein the parameter combination and the parameter value are returned.   When the combination of parameters and the parameter value are returned to the previously used parameter combination and parameter value, or after it is determined that the analysis of the exhaust gas component by the analyzer is possible, the parameter is again set. The automatic adapting device according to claim 6, wherein the devices are sequentially operated in a predetermined operation direction according to a predetermined operation sequence.   Use of parameter combinations and parameter values used when it is determined that the emission component has exceeded a specified value when the parameters are sequentially operated in a predetermined operation direction according to a predetermined operation sequence again. The automatic adaptation device according to claim 7, wherein   When the combination of parameters and the parameter value is returned to the previous parameter combination and parameter value, and the emission component is determined to be less than the previous detection value, the exhaust gas component by the analyzer The automatic adaptation apparatus according to claim 7, wherein it is determined that analysis of   The analyzer is equipped with a purge means for sending air into the exhaust gas extraction path in order to clean the exhaust gas extraction path, and the parameter combination and parameter value used previously are the parameter combination and parameter value. When it is determined that the emission component has exceeded the previous detection value, the purge action of sending air into the exhaust gas extraction path is performed, and when the purge action is performed, the emission component is less than the specified value 8. The automatic adapting device according to claim 7, wherein it is determined that the exhaust gas component can be analyzed by the analyzing device when it is determined that the exhaust gas component has become.   When it is determined that the above emission component has exceeded the specified value when purging is performed, the engine is operated at a high load to incinerate the emission component adhering to and accumulated in the exhaust gas extraction passage. 11. The automatic adaptation device according to claim 10, wherein when it is determined that the emission component has become equal to or less than a specified value, it is determined that the analysis of the exhaust gas component by the analyzer is possible.   The analyzer is equipped with a calibration means for calibrating the analyzer using a reference gas, and the analyzer is calibrated and analyzed when it is determined that the emission component has exceeded a specified value after high-load operation of the engine. 12. The automatic adaptation apparatus according to claim 11, wherein when it is determined that the emission component has become equal to or less than a specified value when the apparatus is calibrated, it is determined that the exhaust gas component can be analyzed by the analyzer.   13. The automatic adapting device according to claim 12, wherein when it is determined that the emission component exceeds a specified value again when the analyzer is calibrated, the analyzing device is determined to be abnormal and the automatic adapting action is stopped. .

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