CN111075543A - Method for regeneration of a diesel particulate filter - Google Patents
Method for regeneration of a diesel particulate filter Download PDFInfo
- Publication number
- CN111075543A CN111075543A CN201910897058.3A CN201910897058A CN111075543A CN 111075543 A CN111075543 A CN 111075543A CN 201910897058 A CN201910897058 A CN 201910897058A CN 111075543 A CN111075543 A CN 111075543A
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- China
- Prior art keywords
- limit value
- soot
- particulate filter
- regeneration
- diesel particulate
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/02—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust
- F01N3/021—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N9/00—Electrical control of exhaust gas treating apparatus
- F01N9/002—Electrical control of exhaust gas treating apparatus of filter regeneration, e.g. detection of clogging
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/02—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust
- F01N3/021—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters
- F01N3/023—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters using means for regenerating the filters, e.g. by burning trapped particles
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
- F01N3/02—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust
- F01N3/021—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters
- F01N3/023—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters using means for regenerating the filters, e.g. by burning trapped particles
- F01N3/025—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters using means for regenerating the filters, e.g. by burning trapped particles using fuel burner or by adding fuel to exhaust
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N2900/00—Details of electrical control or of the monitoring of the exhaust gas treating apparatus
- F01N2900/04—Methods of control or diagnosing
- F01N2900/0408—Methods of control or diagnosing using a feed-back loop
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N2900/00—Details of electrical control or of the monitoring of the exhaust gas treating apparatus
- F01N2900/06—Parameters used for exhaust control or diagnosing
- F01N2900/16—Parameters used for exhaust control or diagnosing said parameters being related to the exhaust apparatus, e.g. particulate filter or catalyst
- F01N2900/1606—Particle filter loading or soot amount
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/10—Internal combustion engine [ICE] based vehicles
- Y02T10/40—Engine management systems
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Processes For Solid Components From Exhaust (AREA)
- Filtering Of Dispersed Particles In Gases (AREA)
Abstract
The present application describes a method for regeneration of a diesel particulate filter (14), comprising the steps of: defining a critical limit value for the soot loading (1); identifying and evaluating (2) a soot load of the diesel particulate filter (14) at the beginning of the regeneration process, and identifying and evaluating an amount of soot combusted during the regeneration process of a defined number of previous regeneration processes of the diesel particulate filter (14); the current limit value of the soot loading for starting the regeneration process is adjusted (7, 8) accordingly, wherein the limit value is increased when at least a first condition (3, 4, 5) exists or is decreased when at least a second condition (6) exists, wherein the current limit value is lower than a defined critical limit value.
Description
Technical Field
The present invention relates to a method for regeneration of a diesel particulate filter. The invention also relates to a device for controlling regeneration of a diesel particulate filter, an exhaust gas treatment device and a vehicle, such as a motor vehicle.
Background
The process of regenerating a particulate filter typically includes two stages. In the first stage, the diesel particulate filter is heated to a target temperature required for soot combustion. In the second stage, the soot deposited in the filter is combusted. While only the second stage contributes to or brings about soot combustion, both stages are relevant in terms of efficiency, in particular in terms of fuel consumption associated with the regeneration process, and/or in terms of oil dilution, for example, in the case of further injection without the use of an evaporator. It is substantially desirable to minimize fuel consumption associated with the regeneration process and to minimize the extent of oil dilution. One possibility in this respect is to delay the filter regeneration process as far as possible, but not to exceed the critical limit value of the soot loading. For example, document US2012/0204537a1 describes an adaptive adjustment of the soot loading, wherein a regeneration process is to be triggered.
Disclosure of Invention
On this background, it is an object of the present invention to provide an advantageous method for the regeneration of a diesel particulate filter, which method in particular increases the efficiency of the regeneration process.
This object is achieved by a method for regeneration of a diesel particulate filter according to claim 1, by an apparatus for controlling regeneration of a diesel particulate filter according to claim 6, by a diesel particulate filter according to claim 7, by an exhaust gas treatment apparatus according to claim 8 and by a vehicle according to claim 10. The dependent claims disclose further advantageous embodiments of the invention.
The method for the regeneration of a diesel particulate filter according to the invention comprises the following steps: first a critical limit value for soot loading is defined. Subsequently, the soot load of the diesel particulate filter at the beginning of the regeneration process and the amount of soot combusted during the regeneration process of a defined number of preceding or immediately preceding regeneration processes of the diesel particulate filter are confirmed and evaluated. Subsequently, the current limit value of the soot load at which the regeneration process is started or initiated or triggered is adjusted accordingly. In this case, the limit value is increased in the presence of at least one first condition or is decreased in the presence of at least one second condition. In this case, the current limit value is adjusted accordingly to a degree below the defined critical limit value.
The described method has the following advantages: so that the current limit value of the soot loading can be adjusted accordingly on the basis of an evaluation of a preceding regeneration process. In this case, the efficiency of the regeneration process can be improved, adjusted with respect to the minimum possible fuel combustion and the maximum combustion.
Preferably, the current limit value is increased if the evaluation of the soot loading shows that the regeneration process is carried out in the case that the average current limit value is smaller than the lower limit value. In a further variant, the current limit value is increased if the evaluation of the soot amount burned during the regeneration process shows that the soot amount burned during the regeneration process increases or can increase with a higher current limit value. In a further variant, the current limit value is increased if the limit value of the soot loading is not reduced during a defined number of preceding or directly preceding regeneration processes. The mentioned variants for increasing the current limit value or at least the first condition with respect to the above-mentioned method improve the efficiency of the regeneration process. In an advantageous manner, the current limit value is increased if all the previously mentioned conditions are met simultaneously, in other words if the evaluation of the soot load indicates that the regeneration process is carried out with an average current limit value smaller than the lower limit value, and if the evaluation of the soot amount burned during the regeneration process indicates that the soot amount burned during the regeneration process is increased or can be increased with a higher current limit value, and if the limit value of the soot load is not decreased during a defined number of preceding or directly preceding regeneration processes.
Preferably, the current limit value is decreased if the evaluation indicates that the regeneration process is performed with the average current limit value being above the upper limit value or above the critical limit value. This variant represents an example of the second condition with respect to the method described above and contributes as such to improving the efficiency of the regeneration process of the diesel particulate filter, in which in particular it is prevented that too close or exceeding a defined critical limit value is exceeded.
Within the scope of the evaluation, for example, an average value of the soot loading at the beginning of the regeneration process and an average value of the soot amount burned during the regeneration process can be specified for a defined number of preceding regeneration processes. Another possibility consists in detecting the development of the soot load and/or the soot amount of the combustion in a functional manner. Further, the amount of soot burned during the regeneration process may be identified and evaluated based on soot loading.
The method according to the invention makes it possible to adaptively adjust the current limit value of the soot loading in order to start or trigger a particle filter regeneration process, wherein above all the efficiency of the regeneration process is increased.
The apparatus for controlling regeneration of a diesel particulate filter according to the present invention includes: means for confirming the soot load of the diesel particulate filter at the beginning of the regeneration process, means for confirming the amount of soot burned during the regeneration process, and evaluation means. The evaluation means is advantageously configured to receive and evaluate data from the means for confirming the soot load of the diesel particulate filter at the start of the regeneration process and data from the means for confirming the amount of soot combusted during the regeneration process. The apparatus according to the invention is configured to implement or perform the above-described method according to the invention. The device according to the invention has the features and advantages mentioned in connection with the method according to the invention.
The diesel particulate filter according to the invention comprises the previously described means for controlling the regeneration of the diesel particulate filter. The exhaust gas treatment device according to the invention comprises the previously described diesel particulate filter according to the invention. The vehicle according to the invention comprises the exhaust gas treatment device according to the invention described earlier. In the case of a vehicle, it is preferably a motor vehicle, such as a passenger car, a commercial truck, a bus, a minibus, a moped or a motorcycle. The diesel particulate filter according to the invention, the exhaust gas treatment device according to the invention and the vehicle according to the invention have the advantages already mentioned in connection with the method according to the invention.
Drawings
The invention is described in detail below with reference to the accompanying drawings by means of exemplary embodiments. Although the invention has been shown and described in further detail with the aid of preferred exemplary embodiments, the invention is not limited to the examples disclosed and further modifications can be derived therefrom by a person skilled in the art without departing from the scope of protection of the invention.
Fig. 1 shows schematically in the form of a flow chart a variant of the method according to the invention for the regeneration of a diesel particulate filter.
Fig. 2 schematically shows an arrangement for controlling regeneration of a diesel particulate filter according to the invention.
Fig. 3 schematically shows a diesel particulate filter according to the invention.
Fig. 4 schematically shows an exhaust gas treatment device according to the invention.
Fig. 5 schematically shows a motor vehicle according to the invention.
Detailed Description
The method according to the invention is further described below with the aid of the flow chart shown in fig. 1. In step 1, a critical limit value for the soot loading of the regeneration process of the diesel particulate filter is specified. In step 2, the soot load of the diesel particulate filter at the beginning of the regeneration process and the amount of soot burnt during the regeneration process of a defined number of preceding or immediately preceding regeneration processes of the diesel particulate filter are confirmed and evaluated. Within the scope of the evaluation, for example, an average value of the soot load at the beginning of the regeneration process and an average value of the soot amount burned during the regeneration process can be specified for a defined number of preceding regeneration processes. Another possibility consists in detecting the development of the soot load and/or the soot amount of the combustion in a functional manner. Further, the amount of soot burned during the regeneration process may be identified and evaluated based on soot loading.
Subsequently, in steps 3 to 5, the prerequisite of increasing the current limit value in step 7 is checked. In this case, if all three prerequisites checked in step 3 to step 5 are fulfilled, then preferably only the current limit value is increased in step 7. Since in some cases it may also be possible to give up individual prerequisites, these prerequisites are represented as separate steps in fig. 1. Step 3, step 4 and step 5 may also be performed in any random other order or simultaneously.
In step 3, the current limit value of the soot loading is adaptively adjusted accordingly as a function of the evaluation result. For this purpose, in step 3, a check is performed as to whether a regeneration process is performed during a defined number of preceding regeneration processes if the average current limit value is smaller than the lower limit value. If this is the case, the current limit value is increased in step 7 and the method then continues with step 2.
If the condition checked in step 3 is not met, in step 4 a check is performed as to whether the soot amount burnt during the regeneration process can be increased or increased in the case of a higher current limit value in the evaluation result of the soot amount burnt during the regeneration process of a defined number of preceding regeneration processes. If this is the case, the current limit value is increased in step 7.
If this is not the case, in step 5 a check is performed as to whether the limit value of the soot loading has not decreased during a defined number of preceding regeneration processes. If this is the case, the current limit value is increased in step 7.
If this is not the case, in step 6 a check is performed as to whether the evaluation indicates that the regeneration process is to be carried out with the average current limit value being above the upper limit value or above the critical limit value. If this is not the case, the method continues with step 2. If this is the case, the current limit value is decreased in step 8 and the method then continues with step 2.
The device for controlling the regeneration of a diesel particulate filter 10, schematically illustrated in fig. 2, comprises: means 11 for confirming the soot load of the diesel particulate filter at the beginning of the regeneration process, and means 12 for confirming the amount of soot burned during the regeneration process. The device further comprises an evaluation device 13, which evaluation device 13 is configured to receive data from the device 11 for confirming the soot load and data from the device 12 for confirming the amount of soot burned. The evaluation device 13 is configured to perform the method according to the invention, in particular the method described in connection with fig. 1.
Fig. 3 schematically shows a diesel particulate filter 14 according to the invention. The diesel particulate filter 14 comprises means for controlling the regeneration of the diesel particulate filter 10, in particular as described in connection with fig. 2.
Fig. 4 schematically shows an exhaust gas treatment device 15 according to the invention. The exhaust gas treatment device 15 comprises a diesel particulate filter 14 as described in connection with fig. 3.
The motor vehicle 16 shown in fig. 5 comprises an internal combustion engine 17 and the exhaust gas treatment device 15 according to the invention described previously.
List of reference numerals
1 limiting the critical limit value of the soot loading
2 determining and evaluating the soot load of the diesel particulate filter at the beginning of the regeneration process and determining and evaluating the amount of soot burnt during the regeneration process of a defined number of preceding regeneration processes of the diesel particulate filter
3 is the regeneration process performed during a defined number of preceding regeneration processes if the average current limit value is smaller than the lower limit value?
4 can the amount of soot combusted during the regeneration process be increased with a higher current limit value?
5 is the limit value of the soot loading not reduced during a defined number of preceding regeneration processes?
6 is the average current limit value above the upper limit value or above the critical limit value the regeneration process is performed?
7 increasing the current limit value
8 decreasing the current limit value
10 device for controlling the regeneration of a diesel particulate filter
11 device for determining the soot loading of a diesel particulate filter at the start of a regeneration process
12 device for confirming the amount of soot burned during a regeneration process
13 evaluation device
14 diesel particulate filter
15 exhaust gas treatment device
16 Motor vehicle
17 internal combustion engine
J is
N is no
Claims (9)
1. A method for regeneration of a diesel particulate filter (14), wherein
The method comprises the following steps:
defining a critical limit value for the soot loading (1),
identifying and evaluating (2) the soot load of the diesel particulate filter (14) at the beginning of the regeneration process and identifying and evaluating the amount of soot combusted during the regeneration process of a defined number of previous regeneration processes of the diesel particulate filter (14),
the current limit value of the soot loading at which the regeneration process is initiated is adjusted (7, 8) accordingly, wherein the limit value is increased in the presence of at least a first condition (3, 4, 5) or is decreased in the presence of at least a second condition (6), wherein the current limit value is below a defined critical limit value.
2. The method of claim 1, wherein
If the evaluation of the soot loading shows that the regeneration process is carried out with an average current limit value smaller than a lower limit value (3), the current limit value is increased (7).
3. The method of claim 1 or 2, wherein
If the evaluation of the soot amount burned during the regeneration process indicates an increase of the soot amount burned during the regeneration process with a higher current limit value (4), the current limit value is increased (7).
4. The method of any one of claims 1 to 3, wherein
If the limit value of the soot loading has not been reduced (5) during a defined number of preceding regeneration processes, the current limit value is increased (7).
5. The method of any one of claims 1 to 4, wherein
If the evaluation indicates that the regeneration process is carried out with an average current limit value above an upper limit value or above the critical limit value (6), the current limit value is reduced (8).
6. An apparatus (10) for controlling regeneration of a diesel particulate filter, wherein
The device comprises means (11) for confirming the soot load of the diesel particulate filter (14) at the beginning of a regeneration process, means (12) for confirming the amount of soot combusted during the regeneration process, and evaluation means (13), and the device (10) is configured to perform the method according to any one of claims 1 to 5.
7. A diesel particulate filter (14) comprising an arrangement (10) for controlling the regeneration of a diesel particulate filter according to claim 6.
8. An exhaust gas treatment device (15) according to claim 7, comprising a diesel particulate filter (14).
9. A vehicle comprising an internal combustion engine (17) and an exhaust gas treatment device (15) according to claim 8.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE102018218052.0A DE102018218052B4 (en) | 2018-10-22 | 2018-10-22 | Process for regenerating a diesel particle filter |
| DE102018218052.0 | 2018-10-22 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111075543A true CN111075543A (en) | 2020-04-28 |
Family
ID=70310264
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910897058.3A Pending CN111075543A (en) | 2018-10-22 | 2019-09-23 | Method for regeneration of a diesel particulate filter |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN111075543A (en) |
| DE (1) | DE102018218052B4 (en) |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4694402B2 (en) | 2006-04-07 | 2011-06-08 | 富士重工業株式会社 | Diesel engine exhaust purification system |
| US8468808B2 (en) | 2010-07-08 | 2013-06-25 | GM Global Technology Operations LLC | Optimization of active regeneration triggers based on ambient and vehicle operating conditions |
| US20120204537A1 (en) | 2011-02-11 | 2012-08-16 | Caterpillar Inc. | Adaptive diesel particulate filter regeneration control and method |
-
2018
- 2018-10-22 DE DE102018218052.0A patent/DE102018218052B4/en active Active
-
2019
- 2019-09-23 CN CN201910897058.3A patent/CN111075543A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| DE102018218052A1 (en) | 2020-04-23 |
| DE102018218052B4 (en) | 2022-09-29 |
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Application publication date: 20200428 |