JP2019183653A - Control device of internal combustion engine - Google Patents

Abstract

To provide a control device of an internal combustion engine which can secure a determination opportunity of an ISC-OBD as much as possible.SOLUTION: As an explanation of a brief overview of a flow of the control of an engine electronic control unit, the learning of ISC is firstly required. When there is a learning completion record, it is determined whether or not the learning is necessary. When assuming that an engine rotation number has been controlled in the vicinity of a target rotational speed, and an ISC-OBD normal determination is finished, an engine is stopped by a learning unnecessity determination. By this constitution, a necessary minimum engine activation time can be obtained, and fuel economy can be also improved. Since an engine activation time can be secured up until a finish of the normal determination, rate establishment performance can be secured. By this control, since the engine is stopped after waiting for the determination of the ISC-OBD, a determination opportunity of the ISC-OBD can be increased.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a control device for an internal combustion engine.

  Conventionally, as disclosed in, for example, Japanese Patent Application Laid-Open No. 2007-196889, a technique for determining whether or not to learn an idle control amount of an internal combustion engine based on a predetermined learning condition is known. The idle control amount is a control amount related to idle speed control (ISC) that is control during idling operation of the internal combustion engine.

JP 2007-196889 A JP 2009-248586 A Japanese Patent Laid-Open No. 10-299550

  In the case of a hybrid vehicle, the engine may be stopped in a short time when it is determined that ISC learning is unnecessary from the viewpoint of improving fuel efficiency. When the engine is stopped in a short time, the engine is stopped without waiting for the determination of ISC-OBD, so that the opportunity for determination of ISC-OBD is reduced.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a control device for an internal combustion engine that can secure an ISC-OBD determination opportunity as much as possible.

A control apparatus for an internal combustion engine according to the present invention includes:
Idle control means for controlling the engine speed during idling of the internal combustion engine based on the learned value;
Learning request means for issuing a signal requesting to perform idle speed control learning for learning the learning value;
Diagnostic determination means for determining that the idle speed control self-diagnosis has been normally performed;
Learning unnecessary determination means including that the idle speed control self-diagnosis has been normally completed as a condition for determining whether or not the idle speed control learning is unnecessary;
Is provided.

  According to the present invention, since the engine is stopped so as to perform the learning unnecessary determination on the condition that the idle speed control self-diagnosis (ISC-OBD) is normally completed, the ISC-OBD determination opportunity is secured as much as possible. be able to.

It is a typical timing chart for demonstrating operation | movement of the control apparatus of the internal combustion engine concerning embodiment. It is a flowchart of the control routine performed in the control apparatus for the internal combustion engine according to the embodiment. It is a flowchart of the control routine performed in the control apparatus for the internal combustion engine according to the embodiment. It is a flowchart of the control routine performed in the control apparatus for the internal combustion engine according to the embodiment. It is a flowchart of the control routine performed in the control apparatus for the internal combustion engine according to the embodiment.

  Before describing the configuration of the embodiment, problems relating to ISC learning will be described. When determining whether ISC learning of a hybrid vehicle is unnecessary, there are cases where establishment of an ISC-OBD rate molecule cannot be achieved. If this state occurs frequently, the rate value, which is a parameter representing the ISC-OBD determination opportunity, becomes small. If the rate value is small, there is a problem that the opportunity of ISC-OBD is reduced.

  This problem will be further described. In the hybrid vehicle, there is a case in which a specification that does not make an ISC request may be incorporated for the purpose of improving fuel efficiency when ISC learning is not necessary. At this time, since the engine is stopped in a short time such as 1.5 seconds at the shortest, there is a possibility that the engine start time required for the ISC-OBD to perform the normal determination may not be secured. In this case, the normal determination is not performed. Not. This necessary engine startup time is, for example, 5 seconds. Since the ISC-OBD molecule needs to have completed the normal determination, the ISC-OBD molecule cannot be established.

  When the engine is stopped in a short time, the engine is stopped without waiting for the determination of the idle speed control self-diagnosis (ISC-OBD), so that the opportunity for determination of ISC-OBD is reduced. That is, in an internal combustion engine in which idle speed control (ISC) is performed, as a measure for improving fuel consumption, the engine may be stopped in the shortest time such as 1.5 seconds when it is determined that ISC learning is not necessary. However, the establishment of the ISC-OBD rate requires that the ISC-OBD normal determination is made, and the engine startup time requires a certain length of time, for example, at least about 5 seconds.

  In order to deal with the above problem, in the embodiment, as a measure for avoiding a case where the rate is not established, a condition of completion of ISC normal determination is added to the ISC learning unnecessary determination condition. The contents of the embodiment will be specifically described below.

  FIG. 1 is a schematic timing chart for explaining the operation of the engine electronic control unit according to the embodiment. In FIG. 1, a time T1 is a precondition fulfillment delay and has a length of about 3 seconds. The time T2 is a normal determination delay and has a length of about 2 seconds. Time T3 is a rate molecule formation delay and has a length of about 5 seconds. When it is determined that ISC learning is unnecessary, the engine is intermittently operated in the shortest time such as 1.5 seconds as shown at time T4, and the rate is not established. In order to determine normality, it is necessary to keep the engine running for some time such as 5 seconds.

  An engine electronic control unit according to an embodiment is a device that controls an internal combustion engine mounted on a hybrid vehicle. The engine electronic control unit according to the embodiment determines engine control means, learning request means for requesting ISC learning, learning unnecessary determination means for determining that ISC learning is unnecessary, and ISC-OBD being normal. Diagnosis determining means for performing the determination, and rate determining means for determining whether or not the ISC-OBD rate is established.

  These means are provided as functions of the engine electronic control unit, and are realized, for example, by executing a program stored in the memory. The engine control means performs known idle operation control. The known idle operation control is not particularly limited, and controls the engine speed during idle operation of the internal combustion engine based on a known learning value.

  2 to 5 are flowcharts of a control routine executed in the engine electronic control unit according to the embodiment. The outline of the control flow of the engine electronic control unit according to the embodiment will be described. First, ISC learning is required according to the routine shown in FIG. When there is a learning completion history, it is determined whether or not learning is necessary according to the routine shown in FIG. Furthermore, it is assumed that the engine rotational speed can be controlled in the vicinity of the target rotational speed and that the ISC-OBD normality determination based on the routine shown in FIG. 4 is completed. In this case, the engine is stopped due to the learning unnecessary determination. As a result, the minimum engine start-up time can be achieved, and fuel consumption can be improved. Since the engine activation time is ensured until the normal determination is completed, rate establishment can be ensured. Note that the routine of FIG. 5 is related to determining whether or not the ISC-OBD rate is established. According to the above control, the engine is stopped after waiting for the determination of ISC-OBD, so that the opportunity for determination of ISC-OBD can be increased.

  The ISC learning request condition will be specifically described with reference to FIG. The routine of FIG. 2 corresponds to “learning request means”. The learning control means issues a signal requesting to perform idle speed control learning for learning the learning value.

  In the embodiment, the request setting condition for setting the ISC learning request flag includes the following first to tenth items. In the embodiment, as an example, it is assumed that the determination result of the request set condition is affirmative (YES) when each of the following first to tenth items is established. In the following description, an example of a flag set or determination formula for each item is also shown.

The first item is that after the engine is started.
exst_exastefi = ON

The second item is that ISC learning is not completed and the ISC learning unnecessary determination is off.
etqiscmng_extqgecok = OFF
extqgok = OFF

The third item is that the water temperature condition of the ISC feedback precondition is satisfied.
etqiscmng_estatus ≥ ETQISCMNG_WARM (3)

The fourth item is that the ISC learning execution water temperature.
ethw_ethw ≧ etqiscmng_THW

The fifth item is that a predetermined time or more has elapsed after the Lo shift. As an example, it is 3000 milliseconds, and there is a case where there is a shift in a hybrid vehicle.
etqiscmng_ecgchglo_65m ≧ etqiscmng_CGCHGLO

The sixth item is the engine intermittent vehicle prohibition vehicle speed for ISC learning.
exspdqg = ON

The seventh item is that the increase coefficient is within a predetermined range. The value of exewup_KRICHL below may be 0.98 times, for example. Further, the value of the following exewup_KRICHH may be, for example, 1.02 times.
exewup_KRICHL <eminj_ekrichx <exewup_KRICHH

The eighth item is that any one of the following sub-items A to C is satisfied. The sub item A is the P range.
ehv_exsftpp = ON

Sub-item B is that it is a cold start. Note that ethw_ethwst is not possible because it is updated at intermittent times.
ethw_ethwint <exewup_THWCST (eg 60 ° C)

Sub-item C is that there is no ISC learning completion history.
etqiscmng_extqgstbl = OFF

The ninth item is that the integrated intake air amount is greater than or equal to a predetermined value. Here, the following t_gasumqg is acquired from egasumqg_map. egasumqg_map is a one-dimensional map by ethw_ethwint.
egacal_egalsum ≧ t_tasumqg

The tenth item is whether or not an abnormality is determined by ISC-OBD.
eiscd_exiscdng = OFF

  If both the first item to the tenth item are established, the determination result of the required set condition is affirmative (YES) in step S100. If the set condition is satisfied in step S100, the ISC learning request flag is set in step S102. Thereafter, the current routine ends.

  The means for determining that ISC learning is not necessary will be specifically described with reference to FIG. The routine of FIG. 3 corresponds to “learning unnecessary determination means”. This learning unnecessary determination means determines whether or not idle speed control learning is necessary. The learning unnecessary determination means according to the embodiment includes that the idle speed control self-diagnosis is normally completed as a condition for the unnecessary determination.

  Specifically, the conditions for determining that ISC learning is not necessary in the embodiment include the following eleventh to fourteenth items. In step S104 according to the embodiment, specifically, it is determined that the ISC learning unnecessary condition is satisfied when each of the following eleventh to fourteenth items is satisfied.

The eleventh item is that ISC feedback is in progress.
etquiscmng_exiscfb = ON

The twelfth item is that it is within a predetermined time from the start of ISC feedback. The predetermined time may be 6000 milliseconds, for example.
etquiscmng_ectqg_16m <exewup_CTQGOK (for example, 6000 milliseconds)

The thirteenth item is that the determination that the ISC learning value deviation is small is established. If the ISC learning value deviation is within a predetermined range, the thirteenth item may be regarded as being established.
extqgsgap = ON

The fourteenth item is that the ISC-OBD normality determination is completed. Since the fourteenth item is provided, the condition for determining that ISC learning is unnecessary can include that the idle speed control self-diagnosis has been completed normally.
eiscd_exjdgpas = ON

  If the determination result of step S104 is affirmative (YES), an ISC learning unnecessary flag is set (step S106). Thereafter, the current routine ends.

  A means for determining that the ISC-OBD is normal will be specifically described with reference to FIG. The routine of FIG. 4 corresponds to “diagnosis determination means”. This diagnosis determination means determines that the idle speed control self-diagnosis (ISC-OBD) has been normally performed. The condition for setting the normal determination flag is that the determination result is affirmative (YES) in both of the two determination condition groups.

  The first determination condition group is a precondition for detection, and the following 15th to 18th items are included in the condition. In the embodiment, as an example, when each of the following fifteenth to eighteenth items is established, the determination result of the first determination condition group is affirmative (YES) in step S108. .

The fifteenth item is that a condition for executing learning is established.
etqiscmng_ectqg_16m ≧ etqiscmng_CTQG (eg 3000 milliseconds)

The sixteenth item is that diagnosis detection is not prohibited in the common rule item.
wobd2msk_xiscKwp = OFF (no OBD2 compliance)

The seventeenth item is that after the start.
exst_exastefi = ON

The eighteenth item is that the diagnosis is not prohibited due to the EGR port blockage or more.
wafimb_fdi_ximbegrc1Mwp = OFF

  If each of the fifteenth to eighteenth items is established, the determination result in step S108 is affirmative (YES).

The condition of the second determination condition group is that the normal determination delay counter is greater than or equal to the determination value. Here, the engine startup time is further required for 2 seconds or more.
ecjiscn_32m ≧ eiscd_TISCP (for example, 2000 milliseconds)

  In step S110, if the normal determination delay counter is greater than or equal to the determination value, the determination result is affirmative (YES).

  When the determination results of both steps S108 and S110 are affirmative (YES), a normal determination flag is set (step S112). If at least one of the determination results of steps S108 and S110 is negative (NO), the process returns without setting the normal determination flag.

  A means for determining whether or not the ISC-OBD rate molecule has been established will be specifically described with reference to FIG. It is determined that the ISC-OBD rate numerator is established when either one of the following first establishment conditions or second establishment conditions is established.

  The first establishment condition includes the following nineteenth to twentieth items. In the embodiment, specifically, in step S114, it is determined that the first satisfaction condition is satisfied when each of the following nineteenth to twentieth items is satisfied.

The nineteenth item is that there was a normal judgment. In the embodiment, the internal combustion engine is constructed so that the engine can be started until this condition is satisfied.
exjdgpas = ON

  The 20th item is that one of the two time condition items described below is established.

The first time condition item is that the learning execution condition is established for a certain time. Here, etqiscmng_CTQG may be set to 3000 milliseconds, for example. Eiscd_CISCLMT may be set to, for example, 5000 milliseconds.
etqiscmng_ectqg_16m ≧ (etqiscmng_CTQG) + eiscd_CISCLMT

The second time condition item is that the rate molecule operation counter has been counted for a certain time or more. This is a hybrid vehicle item. Here, etqiscmng_CTQG may be set to 3000 milliseconds, for example. Eiscd_CISCLMT may be set to, for example, 5000 milliseconds.
ecegstp ≧ etqiscmng_CTQG + eiscd_CISCLMT

  The second satisfaction condition is satisfied when there is an abnormality determination.

  If either the first satisfaction condition or the second satisfaction condition is satisfied, the determination result of step S114 is affirmative (YES), and the rate numerator flag is set (step S116). Thereafter, the current routine ends.

  According to the embodiment described above, the engine is stopped so that the engine is stopped in accordance with the learning unnecessary determination on the condition that the diagnosis of the idle speed control self-diagnosis (ISC-OBD) is normally completed. Can be secured.

Claims (1)

Idle control means for controlling the engine speed during idling of the internal combustion engine based on the learned value;
Learning request means for issuing a signal requesting to perform idle speed control learning for learning the learning value;
Diagnostic determination means for determining that the idle speed control self-diagnosis has been normally performed;
Learning unnecessary determination means including that the idle speed control self-diagnosis has been normally completed as a condition for determining whether or not the idle speed control learning is unnecessary;
A control device for an internal combustion engine.

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