JP5281564B2 - DPF regeneration control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exhaust emission control device for a Diesel engine, which is equipped with a DOC and a DPF in the exhaust passage for performing a regenerative processing for DPF, maintains the inlet temperature of the DPF stably at a level required to make regeneration even for a deterioration with time or a change in environmental conditions. <P>SOLUTION: A late post injection controlling means to control the late post injection amount so that the inlet temperature of the DPF 7 becomes the target temperature 600&deg;C required for regeneration, includes: a late post basic control part 53 to give a command about the late post injection amount so as to obtain the target temperature on the basis of the engine operating conditions; a late post fine adjustment control unit 51 to give fine adjustment, on the basis of the deviation of the actual temperature from the target temperature, to the late post basic amount calculated by the late post basic control part 53; and an update control part 57 to be updated, on the basis of the measuring data during the engine operation, to a late post basic amount map 55 constituting the late post basic control part 53. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a regeneration control device for a diesel particulate filter (hereinafter abbreviated as DPF) for collecting particulate matter (particulate matter, hereinafter abbreviated as PM) contained in exhaust gas of a diesel engine. In particular, the present invention relates to a regeneration control device that stabilizes the DPF inlet temperature against aged deterioration, changes in environmental conditions such as temperature and atmospheric pressure.

In the exhaust gas regulations for diesel engines, PM is as important as NOx reduction. As an effective technique for this, DPF is known.
The DPF is a PM trapping device using a filter. In an engine operating state where the exhaust gas temperature is low, PM continues to be stored in the DPF, so it is necessary to forcibly raise the temperature and burn the PM.
Therefore, a pre-stage oxidation catalyst (hereinafter referred to as DOC) is provided upstream of the DPF, fuel is supplied to the DOC, and the DPF inlet temperature is raised by oxidation heat to reach a predetermined temperature. Need to control.
The fuel supply to the DOC is performed by, for example, a late post injection in which fuel is injected into the combustion chamber of the engine at a timing that does not contribute to combustion and the fuel reaches the DOC through the exhaust passage.

However, there is a possibility that the actual late post-injection amount deviates from the target injection amount set in the map due to deterioration of the fuel injection valve over time, and the regeneration temperature of the DPF cannot be secured.
In addition, when the environmental conditions such as atmospheric temperature and atmospheric pressure change, the post-post injection suitable for the environmental change is not performed because the map value does not correspond to the environmental change, the late post-injection control is not sufficiently performed, and the DPF There was a possibility that the inlet temperature could not be maintained at the regeneration temperature.

  For this reason, an exhaust purification treatment apparatus has been proposed in which the exhaust gas temperature and DPF temperature upstream of the DOC can obtain the target temperature during the DPF regeneration process even if the fuel injection valve or the like deteriorates over time. Document 1 (Japanese Unexamined Patent Application Publication No. 2009-144700) is known.

  This patent document 1 discloses an exhaust gas purification apparatus provided with a DOC and a DPF in an exhaust passage and performing a regeneration process of the DPF, an exhaust gas temperature detecting means for detecting an exhaust gas temperature on the upstream side of the DOC, and an exhaust gas on the downstream side of the DOC. Catalyst temperature detecting means for detecting the temperature or DPF temperature as the catalyst temperature, and the detected value of the exhaust temperature detecting means detected after late post injection and the detected value by the catalyst temperature detecting means are the target exhaust gas. At least one of the late post injection amount or the injection timing is corrected so that the temperature and the target catalyst temperature are obtained.

  More specifically, late post-injection is divided into a total of four cases with a combination of two cases of whether the exhaust temperature is higher than the target exhaust temperature and two cases of whether the catalyst temperature is higher than the target catalyst temperature. By periodically increasing or decreasing the amount or the injection timing for each case, both the exhaust temperature and the catalyst temperature are targeted.

JP 2009-144700 A

  However, the technique disclosed in Patent Document 1 is divided into a total of four cases, two cases of whether the exhaust temperature is higher than the target exhaust temperature and two cases of whether the catalyst temperature is higher than the target catalyst temperature. Since the post-injection amount and the like are controlled, it is difficult to obtain a fine correction with respect to the deterioration with time, and there is a possibility of going back and forth between the four cases and becoming unstable.

  Therefore, the present invention has been made in view of these problems, and in an exhaust gas purification apparatus for a diesel engine provided with a DOC and a DPF in an exhaust passage so that the regeneration process of the DPF is performed. It is an object to stably maintain the DPF inlet temperature at a temperature required for regeneration even during a change.

In order to solve the above problems, the present invention includes a diesel particulate filter (DPF) that collects a pre-stage oxidation catalyst (DOC) and exhaust particulates (PM) in an exhaust passage, and the PM collected in the DPF. And a late post injection control means for performing late post injection using a fuel injection valve at a time that does not directly contribute to combustion after main injection during the regeneration time of the DPF. The post injection control means calculates a late post basic quantity using a late post basic quantity map so that the inlet temperature of the DPF becomes a target temperature necessary for regeneration based on the operating conditions of the engine. And fine adjustment to calculate the late post fine adjustment amount so that it becomes the target temperature based on the deviation between the target temperature required for the regeneration and the actual temperature A control unit, an adder for calculating a late post amount command value by adding the late post basic amount calculated by the late post basic control unit and the late post fine adjustment amount calculated by the fine adjustment amount control unit; And an update control unit that updates the late post basic quantity map constituting the late post basic control unit based on measurement data after engine operation has elapsed ,
The update control unit uses the engine speed, the total injection amount, the oxidation catalyst inlet temperature, and the exhaust gas flow rate when the DPF inlet temperature deviates from a target temperature required for regeneration by a certain amount or more, and a calculation formula Means for calculating a late post basic amount necessary for controlling to the target temperature based on the engine temperature, and the update control unit calculates the engine post speed and the total injection amount when the late post basic amount is calculated by the calculation formula. The calculated late post basic amount is replaced with the value of the late post basic amount map and updated only for the region .

  Here, in the exhaust gas purification apparatus having a DPF that collects DOC and PM in the exhaust passage, the fuel injection in the regeneration control apparatus for the DPF that regenerates the PM collected in the DPF includes main injection and early post injection. Late post injection is described below.

  The main injection is an injection for causing the main combustion in the combustion chamber, and the early post injection means that the pressure in the cylinder immediately after the main injection is still high, and a smaller amount of fuel is injected than the main injection. By this early post injection, the exhaust gas whose temperature has been increased by raising the exhaust gas temperature flows into the DOC, thereby activating the DOC. Thereafter, the second post-injection is further performed with the crank angle after the early post-injection being advanced to the vicinity of the bottom dead center. This second post-injection is called late post-injection, and this late post-injection does not contribute to the combustion in the combustion chamber and is discharged from the combustion chamber to the exhaust passage by the exhaust stroke. The fuel discharged from the combustion chamber reacts in the already activated DOC and further raises the exhaust gas temperature by the generated oxidation heat to about 600 ° C. necessary for regeneration of the DPF to promote PM combustion.

According to the present invention, the late post injection control means for controlling the late post injection amount sets the late post basic amount so that the inlet temperature of the DPF becomes a target temperature required for regeneration based on the operating condition of the engine. A late post basic control unit that calculates using a basic amount map, and a fine adjustment amount control unit that calculates a late post fine adjustment amount so as to reach a target temperature based on a deviation between the target temperature necessary for the regeneration and the actual temperature. And an adder for calculating a late post amount command value by adding the late post basic amount calculated by the late post basic control unit and the late post fine adjustment amount calculated by the fine adjustment amount control unit, and Therefore, it is possible to improve the responsiveness to the target temperature of the DPF inlet temperature and converge stably.

Furthermore, in the present invention with respect to the late post basic amount map which constitute the late post basic control unit, have a update control section for updating based on data measured from the engine during actual operation after the elapse of the engine operation, The update control unit uses the engine speed, the total injection amount, the oxidation catalyst inlet temperature, and the exhaust gas flow rate when the DPF inlet temperature deviates from a target temperature required for regeneration by a certain amount or more, and a calculation formula Means for calculating a late post basic amount necessary for controlling to the target temperature based on the engine temperature, and the update control unit calculates the engine post speed and the total injection amount when the late post basic amount is calculated by the calculation formula. since the late post basic amount the calculated only for the region is updated by replacing the value of the late post-basic amount map, initially set Reitopo The basic value map setting value is updated in response to deterioration over time and changes in environmental conditions, and the DPF inlet temperature is stably maintained at the temperature required for regeneration even during deterioration over time or changes in environmental conditions. .

  Therefore, as the fuel injection valve or the like deteriorates with time, the actual late post injection amount deviates from the target injection amount set in the map, the late post injection is not sufficiently performed, and the regeneration temperature of the DPF cannot be secured. Further, it is possible to reliably avoid the possibility that the late post injection corresponding to the change in the environmental conditions such as the change in the atmospheric temperature and the atmospheric pressure is not sufficiently performed and the DPF inlet temperature cannot be maintained at the regeneration temperature.

In the present invention, it is preferable that the late post basic amount map is a three-dimensional map in which the late post injection amount is set based on the engine speed and the total injection amount contributing to engine combustion.
By using the engine speed and the total injection amount (referring to the fuel amount that contributes to combustion, excluding the late post injection amount), that is, the actual vehicle does not have a dynamometer, and therefore grasps the engine load. By using the total injection amount as a parameter, it is possible to update the map amount based on the measurement data during operation by mapping the engine speed and the total injection amount as parameters representing the engine state during operation. .

Further, the three-dimensional map may be updated based on measurement data including a DOC inlet temperature, an exhaust gas flow rate, an engine speed, and a total injection amount contributing to engine combustion.
Thus, using the DOC inlet temperature Tdoc, the exhaust gas flow rate Ge, the engine speed Ne, and the total injection amount F that contributes to the combustion of the engine, the DOC inlet temperature Tdoc at a certain engine speed Ne and the total injection amount F is DPF. The late post-injection amount necessary for controlling the DPF inlet temperature required for regeneration to about 600 ° C is calculated and updated based on this calculation result, so the rate is reliably determined based on the measurement data during engine operation. The post basic quantity map can be updated.

Further, in the present invention, the DPF inlet temperature update control Ru is executed when deviated constant above the target temperature required for regeneration.

  The update control unit starts late post-injection when the DPF is regenerated, and after that, when the DPF inlet temperature deviates from the target temperature required for regeneration beyond a certain level, for example, it is out of the range of 600 ° C. ± 30 ° C. Sometimes, it is determined that the deviation of the target value of the DPF inlet temperature from 600 ° C. is large, and update control of the late post basic quantity map value is executed.

Furthermore, in the present invention, the update control unit engine speed update control is performed, to update the map only for the total injection quantity of the region.
Rather than updating the entire map, the map is updated only for the operating range (engine speed, total injection amount) where it is determined that the DPF inlet temperature is significantly different from the target value of 600 ° C. As a result, the operating region having a great influence on the change in environmental conditions is updated immediately, and the DPF inlet temperature is stably maintained.

  In the present invention, it is preferable that the update control unit periodically and automatically obtains measurement data and performs update. If the update control is automatically executed based on the engine operation time or the distance traveled in the case of a vehicle, the fluctuation of the late post injection amount due to deterioration with time or changes in environmental conditions can be corrected, and the DPF inlet temperature is regenerated. Can be maintained. As a result, the reliability of the DPF regeneration control device is improved.

According to the present invention, it is provided with late post injection control means for performing late post injection using a fuel injection valve at a time that does not directly contribute to combustion after main injection at the regeneration time of the DPF, and the late post injection control means includes: Based on the engine operating conditions, a late post basic control unit that commands a late post injection amount so that the inlet temperature of the DPF becomes a target temperature required for regeneration, and a basic amount calculated by the late post basic control unit On the other hand, a late post fine adjustment control unit that finely adjusts based on a deviation between the target temperature and the actual temperature, a late post basic amount calculated by the late post basic control unit, and a fine adjustment amount control unit obtained by adding the late post fine adjustment amount for controlling comprises an adder for calculating a late post-amount command value, a, the responsiveness to the temperature of a target inlet temperature of the DPF It is elevated and stable convergence.

Furthermore, in the present invention with respect to the late post basic amount map which constitute the late post basic control unit, have a update control section for updating based on data measured from the engine during actual operation after the elapse of the engine operation, The update control unit uses the engine speed, the total injection amount, the oxidation catalyst inlet temperature, and the exhaust gas flow rate when the DPF inlet temperature deviates from a target temperature required for regeneration by a certain amount or more, and a calculation formula Means for calculating a late post basic amount necessary for controlling to the target temperature based on the engine temperature, and the update control unit calculates the engine post speed and the total injection amount when the late post basic amount is calculated by the calculation formula. since the late post basic amount the calculated only for the region is updated by replacing the value of the late post-basic amount map, initially set Reitopo The basic value map setting value is updated in response to deterioration over time and changes in environmental conditions, and the DPF inlet temperature is stably maintained at the temperature required for regeneration even during deterioration over time or changes in environmental conditions. .

1 is a schematic configuration diagram in which a DPF regeneration control apparatus according to an embodiment of the present invention is applied to a diesel engine. FIG. 2 is a configuration block diagram of a late post injection control unit in FIG. 1. It is a flowchart which shows control of the late post injection control means. It is a flowchart which shows control of an update control part. It is explanatory drawing which shows the acquisition state of the data explaining control of a late post basic quantity map. It is explanatory drawing which shows the outline | summary of a late post basic quantity map. It is explanatory drawing of the specific numerical data in the late post basic quantity map.

  Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the component parts described in this embodiment are not intended to limit the scope of the present invention to that unless otherwise specified.

(Embodiment)
With reference to FIG. 1, an overall configuration in which a DPF regeneration control apparatus according to an embodiment of the present invention is applied to a diesel engine will be described.
As shown in FIG. 1, in an exhaust passage 3 of a diesel engine (hereinafter referred to as an engine) 1, a DOC (pre-stage oxidation catalyst) 5 and a DPF (diesel particulate) that collects PM (particulate matter) on the downstream side of the DOC 5. An exhaust gas aftertreatment device 9 comprising a curate filter) 7 is provided.

  Further, in FIG. 1, the engine 1 includes an exhaust turbocharger 15 having an exhaust turbine 11 and a compressor 13 driven coaxially thereto, and the air discharged from the compressor 13 of the exhaust turbocharger 15. Passes through the air pipe 17 and enters the intercooler 19 where the intake air is cooled, and then the intake air flow rate is controlled by the intake throttle valve 21. Thereafter, the intake port provided for each cylinder is used for the combustion chamber (not shown) of the engine 1. To flow into.

  Further, the engine 1 is provided with a common rail fuel injection device 23 that controls the fuel injection timing and injection amount and injects the fuel into the combustion chamber, and the common rail fuel injection device 23 has a common rail 25 to a fuel injection valve 27. Thus, a predetermined amount of fuel is supplied at a predetermined fuel injection timing, and a control signal is input to the common rail fuel injection device 23 from a regeneration control device 29 described later.

  Further, an EGR (exhaust gas recirculation) pipe 31 is branched from the middle of the exhaust passage 3, and a part of the exhaust gas (EGR gas) is cooled by the EGR cooler 33 through the EGR pipe 31, and the downstream portion of the intake throttle valve 21. Is inserted through the EGR valve 35.

  The combustion gas, that is, the exhaust gas 37 combusted in the combustion chamber of the engine 1 drives the exhaust turbine 11 of the exhaust turbo supercharger 15 through the exhaust manifold and exhaust passage 3 in which exhaust ports provided for each cylinder are gathered. Then, after it becomes a power source for the compressor 13, it enters the DOC 5 of the exhaust gas aftertreatment device 9 through the exhaust passage 3.

  Further, the regeneration control device 29 of the DPF 7 includes a signal from the air flow sensor 39 that detects the air flow rate flowing into the compressor 13, a DOC inlet temperature sensor 41, and a DPF inlet temperature sensor 43, and an engine speed signal 45. Each of the injection amount signals 47 is input.

  The regeneration control device 29 has a late post injection control means 49. The late post injection control means 49 has a late post fine adjustment control section 51, a late post basic control section 53, and the late post basic control section 53. And an update control unit 57 that corrects and updates the map value of the late post basic quantity map 55 constituting the.

  Next, an outline of forced regeneration control by the regeneration control device 29 of the DPF 7 will be described. When the forced regeneration control is started, a DOC temperature raising stage for activating the DOC 5 is executed. In this DOC temperature rising stage, the intake throttle valve 21 is throttled, the exhaust valve provided on the downstream side of the DPF is throttled, and further, the post-main injection is performed after the main injection into the combustion chamber by an engine control means (not shown). Is done.

  When the inlet temperature of the DOC 5 detected by the DOC inlet temperature sensor 41 reaches about 250 ° C., it is determined that the DOC 5 has sufficient activity, and the process proceeds to the DPF combustion control stage that burns and removes the PM deposited on the next DPF 7. . Note that the determination of the transition to the DPF combustion control stage is performed only at the inlet temperature of the DOC 5, and is performed by other control means provided in the regeneration control device 29.

  In this DPF combustion control, late post injection is performed by the late post injection control means 49 at a crank angle that does not contribute to combustion after early post injection (about 180 deg after TDC (top dead center)). In addition, you may make it inject directly into the exhaust passage 3 of the upstream of DOC5 with an exhaust pipe addition valve.

  Then, the exhaust gas temperature is further raised by the oxidation heat generated by the reaction of the late post-injection fuel flowing into the activated DOC 5 in the DOC 5, and the temperature is raised to about 600 ° C. at which PM burns in the DPF 7. Then, PM combustion starts.

  In the regeneration control of the DPF 7 as described above, the late post injection control means 49 calculates and calculates the late post injection amount by the control logic shown in FIG. 2 and outputs it to the common rail fuel injection device 23 as a command value. ing. In the present embodiment, the late post injection amount is controlled, and the late post injection timing is not particularly controlled, and is, for example, constant at about 180 deg after TDC (top dead center).

In the late post basic control unit 53 of FIG. 2, the signals of the total injection amount and the engine speed are input, feedforward control is performed based on the late post basic amount map 55, and output as a late post basic amount component. Is done.
Further, in the late post fine adjustment control unit 51, the feedback between the target DPF inlet temperature 600 ° C. and the actual DPF inlet temperature of the measured value from the DOC inlet temperature sensor 41 is feedback-controlled by a PID device (not shown). And output as a late post fine adjustment component.

Thereafter, the late post basic amount component and the late post fine adjustment amount component are added by the adder 63 to be calculated as a late post amount command value.
Further, as shown in FIG. 6, the late post basic amount map 55 is constituted by a three-dimensional map in which the late post basic amount with respect to the total injection amount and the engine speed is set. Specific numerical values in this map 55 are shown in FIG. 7 in which the total injection amount and the engine rotation speed are stepped, that is, the late post basic amount every 100 rpm and the total injection amount every 5 mg / inj. Is set.

  It should be noted that the engine speed and the basic amount of the late post with respect to the total injection amount at the subdivision points between the shaft increments are used by supplementing the data for each shaft increment by proportional distribution. Further, the late post basic quantity map 55 is updated by the update control unit 57 with a predetermined condition (described later).

Next, the control flow of the update control unit 57 will be described with reference to FIGS.
Starting from step S1, data necessary for map update control is acquired in step S2. As shown in FIG. 2, the data required for the map update includes a total injection amount F (a fuel injection amount obtained by excluding a late post injection amount that does not contribute to combustion from fuel injected during one cycle), and an engine speed Ne. And the DOC inlet temperature Tdoc from the DOC inlet temperature sensor 41 and the exhaust gas flow rate Ge (the air flow rate from the air flow rate sensor 39 + the fuel flow rate (total injection amount (mg / inj) converted into the flow rate (g / s)) )).

  In step S3, at the time of DPF regeneration control, it is determined by the signal from the DPF inlet temperature sensor 43 whether or not the DPF inlet temperature is in the range of about 600 ° C. (for example, 600 ° C. ± 30 ° C.). It is determined whether or not it is far away from the temperature.

  In step S3, if the DPF inlet temperature is outside the range of about 600 ° C., the characteristics of the common rail fuel injection device 23 change due to aging, and the actual injection amount changes even if the late post injection command value is the same. Or the setting value of the late post basic quantity map 55 does not match the outside air temperature due to a change in the outside air temperature. The process proceeds to step S4, and the late post basic quantity map 55 needs to be updated. This is displayed on the monitor, and in step S5, update control of the late post basic quantity map 55 is executed.

  In step S3, if the DPF inlet temperature is in the range of about 600 ° C. (for example, 600 ° C. ± 30 ° C.), there is an incompatibility with the aging deterioration of the fuel injection device and the set value of the late post basic quantity map 55. It is determined that there is no map value update, and the reproduction control proceeds using the current late post basic quantity map 55, and ends in step S6.

Next, a specific procedure of the update control in step S5 will be described with reference to FIG.
In step S11, the data already acquired in step S2 is acquired again in step S12. In the next step S13, data is extracted when the DOC inlet temperature Tdoc is about 250 ° C. or higher and the DPF inlet temperature is outside the range of about 600 ° C. (eg, 600 ° C. ± 30 ° C.). An image of the extracted data is shown in FIG. Data is acquired in units of 1200 seconds, and data that satisfies the conditions of the DOC inlet temperature Tdoc and the DPF inlet temperature is extracted.

  In step S14, based on the data extracted in step S13, arbitrary numerical values of the shaft rotation engine speed Ne and the total injection amount F in the numerical data table of the late post basic amount map 55 of FIG. 7, for example, 50 mg / inj at 1300 rpm. Is selected (shaded area in FIG. 7), and the time t1 in FIGS. 5A and 5B that satisfies both 1300 rpm and 50 mg / inj is extracted. Since it is difficult to extract the time t1 when the engine speed Ne and the total injection amount F coincide with each other, a certain range, for example, 1300 rpm ± 10 rpm, and the total injection amount F are extracted as 50 ± 0.1 mg / inj.

  In step S15, the DOC inlet temperature Tdoc and the exhaust gas flow rate Ge in FIGS. 5C and 5D corresponding to the time t1 are extracted. In addition, when a plurality of DOC inlet temperatures Tdoc and exhaust gas flow rates Ge are extracted within a certain time period, the average values thereof are adopted and obtained.

  Necessary for controlling the DPF inlet temperature to 600 ° C. in step S16 using the engine speed Ne, the total injection amount F already extracted in step S14, the DOC inlet temperature Tdoc extracted in step S15, and the exhaust gas flow rate Ge. The basic late post amount Lp is calculated.

In this calculation, the calorific value Qp for controlling to 600 ° C. is calculated by the equation (1), and the calorific value q when the calorific value corresponding to the calculated calorific value Qp is converted into the light oil true calorific value Qf is calculated by the equation. Calculate in (2). At this time, since all of the light oil that has been late post-injected and injected into the combustion chamber does not reach the DOC, the relationship (effective rate η) between the late post-injection amount command and the amount of light oil that actually reaches the DOC is considered. This effective rate η is set as a map of the engine speed and the total injection amount.
Further, the late post basic amount Lp is calculated by the equation (3) in terms of the injection amount per injection. Note that the late post basic amount Lp corresponding to the difference in fuel can be calculated by changing the light oil true calorific value Qf.
Qp = (600−Tdoc) × Ge × exhaust gas constant pressure molar specific heat / exhaust gas average molecular weight
(J / s) (1)
q = Qp / Qf / η (g / s) (2)
Lp = 1000 × q / (Ne / 60) / number of cylinders / (2 / number of cycles)
(Mg / inj) (3)

  In step S17, the late post basic amount map 55 is updated by replacing the shaded portion in FIG. 7 with the calculation result obtained in step S16 as the late post basic amount at the engine speed Ne and the total injection amount F selected in step S14. The process ends in step S18.

  Thus, as shown in A of FIG. 6, the map is updated only for the region of the engine speed Ne and the total injection amount F for which the update control is executed. Therefore, the operation region having a great influence on the deterioration with time and the change of the environmental condition is quickly updated, and the DPF inlet temperature is stably maintained.

In addition, about the above update control, the said update control part 57 performs an update by acquiring measurement data automatically automatically regularly.
Since update control is automatically executed based on the engine operation time and the mileage in the case of a vehicle, it is possible to automatically correct and update fluctuations in the late post injection amount due to deterioration over time and changes in environmental conditions, The DPF inlet temperature can be stably maintained at the target temperature of 600 ° C. necessary for regeneration, and the reliability of the regeneration control device for the DPF 7 can be improved.

In addition, with regard to update control, instead of automatically executing update control based on the engine operation time or the travel distance in the case of a vehicle, if the engine operation time or the vehicle travel distance reaches a certain value, The storage of the acquisition data necessary for the update control is started, and thereafter, processing is performed at the vehicle dealer (dealer, maintenance shop, etc.) according to the steps S13 to S17 based on the stored data. The entire range of the engine speed Ne and the total injection amount F in the shaft increment in the numerical data table of the No. 7 late post basic amount map 55 may be updated at a time.
Thus, when the map data is updated at a dealer or the like at once, it is recognized by the driver that the map data has been updated.

  As described above, according to the present embodiment, not only the late post basic control unit 53 that commands the late post basic quantity so that the inlet temperature of the DPF 7 becomes the target temperature of 600 degrees necessary for regeneration, but also the late post basic unit. In order to control the basic amount calculated by the control unit 53 with a late post fine adjustment control unit 51 that finely adjusts based on a deviation between the target temperature of 600 ° C. and the actual temperature, the inlet temperature of the DPF is set as a target. It is possible to improve the responsiveness to temperature and to achieve stable convergence.

  Furthermore, since the late post basic quantity map 55 constituting the late post basic control section 53 has an update control section 57 that updates the late post basic quantity map 55 based on measurement data during operation after engine operation, the late post basic quantity initially set is provided. The set value of the map 55 can be updated in response to deterioration with time and changes in environmental conditions. As a result, the inlet temperature of the DPF is stably maintained at the temperature required for regeneration even when it deteriorates with time or when environmental conditions change.

  Since the late post basic quantity map 55 is composed of a three-dimensional map in which the late post basic quantity is set based on the engine speed Ne and the total injection quantity contributing to engine combustion, there is no dynamometer in an actual vehicle. Therefore, by using the total injection amount to grasp the engine load, it is mapped based on the measured data during operation by mapping the engine speed and the total injection amount as parameters representing the engine state during operation. The value can be easily updated.

  According to the present invention, in a diesel engine exhaust gas purification apparatus provided with a DOC and a DPF in an exhaust passage so as to perform a regeneration process of the DPF, the late post basic amount is updated even when deterioration occurs with time or when environmental conditions change. As a result, the DPF inlet temperature can be stably maintained at the temperature required for regeneration.

1 Diesel engine 3 Exhaust passage 5 DOC (Pre-stage oxidation catalyst)
7 DPF (diesel particulate filter)
9 Exhaust gas aftertreatment device 15 Exhaust turbocharger 23 Common rail fuel injection device 25 Common rail 27 Fuel injection valve 29 Regeneration control device 39 Air flow sensor 41 DOC inlet temperature sensor 43 DPF inlet temperature sensor 45 Engine speed signal 47 Fuel injection amount signal 49 Late Post Injection Control Means 51 Late Post Fine Adjustment Control Unit 53 Late Post Basic Control Unit 55 Late Post Basic Quantity Map 57 Update Control Unit

Claims (4)

In a DPF regeneration control device that includes a diesel particulate filter (DPF) that collects a pre-stage oxidation catalyst (DOC) and exhaust particulates (PM) in an exhaust passage, and that regenerates the PM collected in the DPF.
Late post-injection control means for performing late post-injection using a fuel injection valve at a time that does not directly contribute to combustion after main injection at the regeneration time of the DPF,
The late post injection control means calculates a late post basic amount using a late post basic amount map so that the inlet temperature of the DPF becomes a target temperature required for regeneration based on an operating condition of the engine. A control unit;
A fine adjustment amount control unit for calculating a late post fine adjustment amount so as to be a target temperature based on a deviation between the target temperature and the actual temperature necessary for the regeneration;
An adder that calculates the late post amount command value by adding the late post basic amount calculated by the late post basic control unit and the late post fine adjustment amount calculated by the fine adjustment amount control unit;
An update control unit that updates the late post basic quantity map constituting the late post basic control unit based on measurement data after engine operation has elapsed ,
The update control unit uses the engine speed, the total injection amount, the oxidation catalyst inlet temperature, and the exhaust gas flow rate when the DPF inlet temperature deviates from a target temperature required for regeneration by a certain amount or more, and a calculation formula Means for calculating a late post basic amount required for controlling to the target temperature based on
The update control unit replaces the calculated late post basic amount with the value of the late post basic amount map only for the engine speed and total injection amount regions when the late post basic amount is calculated by the calculation formula. The DPF regeneration control apparatus is characterized in that it is updated .   2. The DPF according to claim 1, wherein the late post basic amount map is constituted by a three-dimensional map in which the late post basic amount is set based on an engine speed and a total injection amount contributing to engine combustion. Playback control device.   3. The DPF regeneration according to claim 2, wherein the three-dimensional map is updated based on measurement data including a DOC inlet temperature, an exhaust gas flow rate, an engine speed, and a total injection amount contributing to engine combustion. Control device. The DPF regeneration control apparatus according to claim 1, wherein the update control unit automatically performs update by periodically acquiring measurement data .

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