CN115163267A - DOC (document management interface) diagnosis method and aftertreatment system - Google Patents
DOC (document management interface) diagnosis method and aftertreatment system Download PDFInfo
- Publication number
- CN115163267A CN115163267A CN202211034325.2A CN202211034325A CN115163267A CN 115163267 A CN115163267 A CN 115163267A CN 202211034325 A CN202211034325 A CN 202211034325A CN 115163267 A CN115163267 A CN 115163267A
- Authority
- CN
- China
- Prior art keywords
- doc
- conversion efficiency
- judging whether
- excessive
- equal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000000034 method Methods 0.000 title claims abstract description 34
- 238000003745 diagnosis Methods 0.000 title claims abstract description 24
- 238000006243 chemical reaction Methods 0.000 claims abstract description 168
- 230000002159 abnormal effect Effects 0.000 claims abstract description 26
- 238000012805 post-processing Methods 0.000 claims abstract description 12
- 230000008929 regeneration Effects 0.000 claims abstract description 11
- 238000011069 regeneration method Methods 0.000 claims abstract description 11
- 238000002347 injection Methods 0.000 claims description 97
- 239000007924 injection Substances 0.000 claims description 97
- 238000002405 diagnostic procedure Methods 0.000 claims description 14
- 239000000446 fuel Substances 0.000 claims description 13
- 206010021198 ichthyosis Diseases 0.000 claims 38
- 230000005856 abnormality Effects 0.000 abstract description 3
- 230000006866 deterioration Effects 0.000 abstract 1
- 238000011144 upstream manufacturing Methods 0.000 description 28
- 239000003921 oil Substances 0.000 description 22
- 238000002474 experimental method Methods 0.000 description 10
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 6
- 229910052717 sulfur Inorganic materials 0.000 description 6
- 239000011593 sulfur Substances 0.000 description 6
- 230000032683 aging Effects 0.000 description 5
- 231100000572 poisoning Toxicity 0.000 description 4
- 230000000607 poisoning effect Effects 0.000 description 4
- 239000003054 catalyst Substances 0.000 description 2
- 238000002485 combustion reaction Methods 0.000 description 2
- 239000000295 fuel oil Substances 0.000 description 2
- 150000002894 organic compounds Chemical class 0.000 description 2
- 230000007704 transition Effects 0.000 description 2
- 230000006978 adaptation Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Images
Classifications
-
- 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
- F01N11/00—Monitoring or diagnostic devices for exhaust-gas treatment apparatus, e.g. for catalytic activity
-
- 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
- F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
- F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
- F01N3/18—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control
- F01N3/20—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control specially adapted for catalytic conversion ; Methods of operation or control of catalytic converters
-
- 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
- F01N2550/00—Monitoring or diagnosing the deterioration of exhaust systems
- F01N2550/02—Catalytic activity of catalytic converters
-
- 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
- F01N2900/1621—Catalyst conversion efficiency
-
- 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)
- Chemical Kinetics & Catalysis (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Health & Medical Sciences (AREA)
- Toxicology (AREA)
- Exhaust Gas After Treatment (AREA)
Abstract
The invention discloses a DOC (document order management) diagnosis method and a postprocessing system, wherein the DOC diagnosis method comprises the following steps of: calculating first HC conversion efficiency after DOC work lasts for a first duration after the DPF enters passive regeneration; judging whether the HC conversion efficiency of the DOC is abnormal or not according to the first HC conversion efficiency; if the HC conversion efficiency of the DOC is abnormal, the DOC enters a first heat management mode and calculates second HC conversion efficiency; judging whether HC attached to the surface of the DOC is excessive or not according to the second HC conversion efficiency; if the HC attached to the surface of the DOC is not excessive, the DOC enters a second heat management mode, and third HC conversion efficiency is calculated; and judging whether the SOF attached to the surface of the DOC is excessive according to the third HC conversion efficiency, and judging whether the DOC is aged. It is possible to diagnose whether the HC conversion efficiency abnormality of the DOC is the HC excess adhering to the surface of the DOC, the SOF excess adhering to the surface of the DOC, or the DOC deterioration.
Description
Technical Field
The invention relates to the technical field of vehicle aftertreatment, in particular to a DOC (vehicle information center) diagnosis method and an aftertreatment system.
Background
Currently, due to emission legislation, it is desirable to add an aftertreatment system to an engine system and convert engine exhaust gas over a supported catalyst within the aftertreatment system. The aftertreatment system mainly includes a DOC (Diesel Oxidation Catalyst), a DPF (Diesel Particulate Filter), and the like, so that the DOC is one of important components in the aftertreatment system, and the working performance of the DOC directly affects the working performance of the DPF.
Among these, there are multiple factors that cause poor operation of the DOC, such as: the method comprises the steps of determining the amount of HC attached to the surface of the DOC, determining whether the amount of the SOF (Soluble Organic compound) attached to the surface of the DOC is excessive to cause sulfur poisoning, determining whether the SOF (Soluble Organic compound) attached to the surface of the DOC is excessive to cause DOC aging and the like, wherein particularly when a vehicle runs in a low-temperature environment, the low temperature can increase the amount of the HC attached to the surface of the DOC and can aggravate the DOC sulfur poisoning. However, the DOC diagnosis method in the prior art can only be used for diagnosing whether the DOC is poisoned by sulfur, but cannot diagnose other factors causing poor working performance of the DOC, and the reliability is poor.
Disclosure of Invention
The invention aims to provide a DOC (document information management) diagnosis method and a DOC post-processing system, and solve the problems that other factors causing poor working performance of DOC cannot be diagnosed by the DOC diagnosis method in the prior art, and the reliability is poor.
In order to achieve the purpose, the invention adopts the following technical scheme:
a DOC diagnostic method, comprising:
after the DPF enters the passive regeneration, calculating first HC conversion efficiency after DOC works for a first duration;
judging whether the HC conversion efficiency of the DOC is abnormal or not according to the first HC conversion efficiency;
if the HC conversion efficiency of the DOC is abnormal, the DOC enters a first heat management mode, and second HC conversion efficiency of the DOC after the first heat management mode is calculated;
judging whether HC attached to the surface of the DOC is excessive according to the second HC conversion efficiency;
if the HC attached to the surface of the DOC is not excessive, the DOC enters a second heat management mode, and third HC conversion efficiency of the DOC after the DOC is in the second heat management mode is calculated;
and judging whether the SOF attached to the surface of the DOC is excessive according to the third HC conversion efficiency, and judging whether the DOC is aged.
Preferably, the specific steps of entering a first thermal management mode by the DOC and calculating the second HC conversion efficiency of the DOC after the first thermal management mode include:
adjusting the opening of a throttle valve and/or the oil injection quantity of an aftertreatment system to enable the temperature of the DOC to be a first set temperature and last for a second duration;
controlling the post-processing system to perform oil injection for the first time, and recording the first oil injection duration;
calculating a first HC injection amount in the first injection period;
judging whether the first HC injection quantity is larger than or equal to a first set HC injection quantity or not;
the second HC conversion efficiency is calculated if the first HC injection amount is equal to or greater than a first set HC injection amount.
Preferably, the first set temperature is 300 ℃.
Preferably, the specific steps of entering a second thermal management mode by the DOC and calculating a third HC conversion efficiency of the DOC after the second thermal management mode include:
adjusting the temperature of the DOC to be a second set temperature by adjusting the opening of the throttle valve and/or the fuel injection quantity of the aftertreatment system, and continuing for a third duration;
controlling the post-processing system to perform oil injection for the second time, and recording the second oil injection duration;
calculating a second HC injection amount in the second injection period;
judging whether the second HC injection quantity is larger than or equal to a second set HC injection quantity or not;
the third HC conversion efficiency is calculated if the second HC injection amount is equal to or greater than a second set HC injection amount.
Preferably, the second set temperature is 600 ℃.
Preferably, the specific step of determining whether the HC conversion efficiency of the DOC is abnormal or not based on the first HC conversion efficiency includes:
judging whether the first HC conversion efficiency is larger than or equal to a first set HC conversion efficiency;
if the first HC conversion efficiency is larger than or equal to a first set HC conversion efficiency, the HC conversion efficiency of the DOC is normal;
and if the first HC conversion efficiency is smaller than a first set HC conversion efficiency, the HC conversion efficiency of the DOC is abnormal.
Preferably, the specific step of judging whether the HC coverage of the DOC surface is excessive according to the second HC conversion efficiency includes:
judging whether the second HC conversion efficiency is larger than or equal to a second set HC conversion efficiency;
if the second HC conversion efficiency is larger than or equal to a second set HC conversion efficiency, the amount of HC adhered to the surface of the DOC is excessive;
if the first HC conversion efficiency is less than a first set HC conversion efficiency, the amount of HC adhered to the surface of the DOC is not excessive.
Preferably, the specific steps of determining whether the amount of SOF adhered to the surface of the DOC is excessive according to the third HC conversion efficiency, and determining whether the DOC is aged, include:
judging whether the third HC conversion efficiency is greater than or equal to a third set HC conversion efficiency;
if the third HC conversion efficiency is larger than or equal to a third set HC conversion efficiency, the amount of SOF attached to the surface of the DOC is excessive;
and if the first HC conversion efficiency is smaller than a first set HC conversion efficiency, the DOC is aged.
Preferably, the first set HC conversion efficiency is equal to or less than the second set HC conversion efficiency is equal to or less than the third set HC conversion efficiency.
An aftertreatment system for implementing the DOC diagnostic method described above.
The invention has the beneficial effects that:
the invention aims to provide a DOC (document information management) diagnosis method and a post-processing system, wherein the DOC diagnosis method comprises the following steps: the DPF lasts for a first duration after entering the passive regeneration, and the first HC conversion efficiency of the DOC is calculated; judging whether the HC conversion efficiency of the DOC is abnormal or not according to the first HC conversion efficiency; if the HC conversion efficiency of the DOC is abnormal, the DOC enters a first heat management mode, the DOC is heated and insulated after the first heat management mode, so that the temperature of the DOC is enough to convert HC on the surface of the DOC, and then the second HC conversion efficiency of the DOC after the first heat management mode is calculated; judging whether the HC coverage amount of the DOC surface is excessive according to the second HC conversion efficiency, wherein if the second HC conversion efficiency is improved, the HC coverage amount attached to the DOC surface is excessive; if the HC coverage on the surface of the DOC is not excessive, the DOC enters a second heat management mode, the DOC is heated and insulated again after the second heat management mode, so that the temperature of the DOC is enough to pyrolyze SOF attached to the surface of the DOC, and then the third HC conversion efficiency of the DOC after the second heat management mode is calculated; judging whether the SOF attached to the surface of the DOC is excessive according to the third HC conversion efficiency, and judging whether the DOC is aged, wherein if the third HC conversion efficiency is improved, the SOF attached to the surface of the DOC is excessive, otherwise, the DOC is aged. Therefore, whether the HC conversion efficiency of the DOC is abnormal or not can be diagnosed through the DOC diagnosis method, if the HC conversion efficiency of the DOC is abnormal, the DOC diagnosis method can diagnose that the reason of the HC conversion efficiency abnormality of the DOC is caused by the excess of the HC adhered to the surface of the DOC, the excess of the SOF adhered to the surface of the DOC and the aging of the DOC, so that the DOC can be accurately managed or replaced, and the DOC diagnosis method is high in reliability.
Drawings
Fig. 1 is a flowchart of a DOC diagnostic method according to an embodiment of the present invention.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.
In the description of the present invention, unless expressly stated or limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, e.g., as meaning permanently connected, removably connected, or integral to one another; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
In the present invention, unless expressly stated or limited otherwise, the recitation of a first feature "on" or "under" a second feature may include the recitation of the first and second features being in direct contact, and may also include the recitation that the first and second features are not in direct contact, but are in contact via another feature between them. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.
In the description of the present embodiment, the terms "upper", "lower", "right", etc. are used based on the orientations or positional relationships shown in the drawings for convenience of description and simplicity of operation, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used only for descriptive purposes and are not intended to have a special meaning.
DOC is one of the important components in an aftertreatment system, whose performance directly affects the performance of the DPF. Among these, there are multiple factors that cause poor operation of the DOC, such as: the HC attached to the DOC surface is excessive, whether the SOF (Soluble Organic Fraction) attached to the DOC surface is excessive or not causes sulfur poisoning, DOC aging and the like, especially when a vehicle runs in a low-temperature environment, the HC attached amount on the DOC surface is increased due to low temperature, and DOC sulfur poisoning is aggravated. However, the DOC diagnosis method in the prior art can only be used for diagnosing whether the DOC is poisoned by sulfur, but cannot diagnose other factors causing poor working performance of the DOC, and the reliability is poor.
The invention provides a DOC diagnosis method for diagnosing the working performance of a DOC in an aftertreatment system, whether the HC conversion efficiency of the DOC is abnormal or not can be diagnosed through the DOC diagnosis method, if the HC conversion efficiency of the DOC is abnormal, the reason that the HC conversion efficiency of the DOC is abnormal can be diagnosed through the DOC diagnosis method is caused by one of excessive HC attached to the surface of the DOC, excessive SOF attached to the surface of the DOC and aging of the DOC, so that the DOC can be accurately managed or replaced, and the DOC diagnosis method is high in reliability.
As shown in fig. 1, the DOC diagnostic method includes:
s100, judging whether the DPF is in a passive regeneration working state or not.
If the DPF is in the passive regeneration operation state, the process proceeds to step S200.
If the DPF is not in the passive regeneration operating state, step S110 is performed.
And S110, triggering the DPF to perform passive regeneration. After the DPF enters the passive regeneration, the process proceeds to step S200.
S200, after the DPF enters the passive regeneration, calculating first HC conversion efficiency after DOC works for a first duration.
Wherein, the temperature of the DOC is increased through the first duration after the DPF enters the passive regeneration, so as to ensure that the calculated value of the first HC conversion efficiency is effective. It will be appreciated that the value of the first duration is sufficiently large that the temperature of the DOC rises to a normal operating temperature. Wherein the first duration is an empirical value obtained from a large number of experiments in the early stage.
Specifically, an upstream temperature sensor is disposed upstream of the DOC, and a downstream temperature sensor is disposed downstream of the DOC.
Further specifically, a first upstream temperature value is measured by an upstream temperature sensor of the DOC, a first downstream temperature value is measured by a downstream temperature sensor of the DOC, and the first HC conversion efficiency is calculated from the first upstream temperature value and the first downstream temperature value.
More specifically, the formula for calculating the first HC conversion efficiency from the first upstream temperature value and the first downstream temperature value is:
wherein, T 11 A first upstream temperature value, DEG C; t is 12 A first downstream temperature value, deg.C; t is 13 A first upstream theoretical temperature value, deg.C; t is 14 Is the first downstream theoretical temperature value, deg.C. Wherein, when calculating the first HC conversion efficiency, the integration time period is a first set time period after the first duration.
And the first upstream theoretical temperature value and the first downstream theoretical temperature value are obtained by calculating the theoretical oil injection quantity of the post-processing system. The first set time period is an empirical value obtained through a large number of experiments in the early stage.
The method for calculating the first upstream theoretical temperature value and the first downstream theoretical temperature value through the theoretical fuel injection quantity of the aftertreatment system belongs to the prior art and is not described herein again.
S300, judging whether the HC conversion efficiency of the DOC is abnormal or not according to the first HC conversion efficiency.
Specifically, the specific step of judging whether the HC conversion efficiency of the DOC is abnormal or not according to the first HC conversion efficiency includes:
it is determined whether the first HC conversion efficiency is equal to or greater than a first set HC conversion efficiency.
If the first HC conversion efficiency is greater than or equal to the first set HC conversion efficiency, the HC conversion efficiency of the DOC is normal.
If the first HC conversion efficiency is less than the first set HC conversion efficiency, the HC conversion efficiency of the DOC is abnormal. Step S400 is performed.
In this way, whether the HC conversion efficiency of the DOC is abnormal or not is preliminarily diagnosed by the first set HC conversion efficiency. It can be understood that if the HC conversion efficiency of the DOC is normal, the DOC diagnosis method is ended, and the DOC operates normally.
The first set HC conversion efficiency is an empirical value obtained from a large number of previous experiments.
S400, the DOC enters a first heat management mode, and second HC conversion efficiency of the DOC after the DOC enters the first heat management mode is calculated.
Specifically, the specific steps of entering the first thermal management mode by the DOC and calculating the second HC conversion efficiency of the DOC after the first thermal management mode include:
and S410, adjusting the opening of the throttle valve and/or the oil injection quantity of the aftertreatment system to enable the temperature of the DOC to be the first set temperature and last for a second duration.
The opening of the throttle valve and the oil injection quantity of the aftertreatment system are empirical values obtained through a large number of experiments in the early stage. It is sufficient to ensure that the temperature of the DOC rises to the first set temperature.
Wherein the first set temperature is 300 ℃. Specifically, if the amount of HC adhered to the surface of the DOC is excessive, the first set temperature is sufficient to convert the HC adhered to the surface of the DOC when the temperature of the DOC reaches the first set temperature.
And setting the temperature of the DOC as the first set temperature and then continuing for a second duration time, so that the temperature of the DOC is continuously 300 ℃ to ensure that the value of the second HC conversion efficiency obtained by subsequent calculation is effective.
Wherein the second duration is an empirical value obtained from a large number of experiments in the early stage. In the present embodiment, the second duration is 1 hour.
And S420, controlling the post-processing system to perform first oil injection, and recording the first oil injection duration.
The DOC temperature is a first set temperature by adjusting the oil injection quantity of the aftertreatment system, and the first oil injection is the post-injection oil injection of the engine. The post injection of the engine refers to that after the main injection, the fuel oil with accurate measurement is injected into the combustion chamber in the crank angle of 120-180 ℃ after the exhaust top dead center. The main injection refers to a process of injecting fuel into a cylinder in a normal process of the engine.
S430, calculating a first HC injection amount in the first fuel injection period.
S440, whether the first HC injection amount is larger than or equal to a first set HC injection amount is judged.
If the first HC injection amount is equal to or greater than the first set HC injection amount, the second HC conversion efficiency is calculated.
It is understood that if the first HC injection amount is smaller than the first set HC injection amount, the first fuel injection is continued until the first HC injection amount is equal to or larger than the first set HC injection amount.
Specifically, if the first HC injection amount in the injection amount of the first injection is equal to or greater than the first set HC injection amount, a significant temperature difference is made between the upstream temperature and the downstream temperature of the DOC during the transition of the first HC injection amount to ensure that the calculated value of the second HC conversion efficiency is valid.
Further specifically, a second upstream temperature value is measured by an upstream temperature sensor of the DOC, a second downstream temperature value is measured by a downstream temperature sensor of the DOC, and the second HC conversion efficiency is calculated according to the second upstream temperature value and the second downstream temperature value.
More specifically, the formula for calculating the second HC conversion efficiency according to the second upstream temperature value and the second downstream temperature value is:
wherein, T 21 A second upstream temperature value, deg.C; t is 22 A second downstream temperature value, deg.C; t is 23 A second upstream theoretical temperature value, deg.C; t is 24 The second downstream theoretical temperature value, deg.C. And when the second HC conversion efficiency is calculated, the integral time period is a second set time length after the first fuel injection is finished.
And calculating the second upstream theoretical temperature value and the second downstream theoretical temperature value by the theoretical oil injection quantity of the post-processing system. The second set time period is an empirical value obtained through a large number of experiments in the early stage.
The method for calculating the second upstream theoretical temperature value and the second downstream theoretical temperature value through the theoretical oil injection quantity of the aftertreatment system belongs to the prior art and is not described herein again.
In this embodiment, steps S420 to S440 may be performed simultaneously or sequentially.
And S500, judging whether the HC adhered to the surface of the DOC is excessive according to the second HC conversion efficiency.
Specifically, the specific step of judging whether the HC adhered to the surface of the DOC is excessive according to the second HC conversion efficiency includes:
it is determined whether the second HC conversion efficiency is equal to or greater than a second set HC conversion efficiency.
If the second HC conversion efficiency is equal to or greater than the second set HC conversion efficiency, the amount of HC deposited on the DOC surface becomes excessive. The DOC diagnostic method is ended and it is determined that the cause of the HC conversion efficiency abnormality of the DOC is excessive HC adhered to the surface of the DOC.
If the first HC conversion efficiency is less than the first set HC conversion efficiency, the amount of HC deposited on the surface of the DOC is not excessive. Step S600 is performed.
Among them, the second set HC conversion efficiency is an empirical value obtained from a large number of experiments in the early stage.
And S600, the DOC enters a second heat management mode, and the third HC conversion efficiency of the DOC in the second heat management mode is calculated.
Specifically, the specific steps of entering the second thermal management mode by the DOC and calculating the third HC conversion efficiency of the DOC after the second thermal management mode include:
and S610, adjusting the temperature of the DOC to be a second set temperature by adjusting the opening of the throttle valve and/or the fuel injection quantity of the aftertreatment system, and continuing for a third duration.
The opening of the throttle valve and the fuel injection quantity of the aftertreatment system are empirical values obtained through a large number of previous experiments. It is sufficient to ensure that the temperature of the DOC rises to the second set temperature.
Wherein the second set temperature is 600 ℃. Specifically, if the amount of SOF adhered to the surface of the DOC is excessive, the second set temperature is sufficient to convert the SOF adhered to the surface of the DOC when the temperature of the DOC reaches the second set temperature.
And after the temperature of the DOC is set to be the second set temperature, the DOC lasts for a third duration, so that the temperature of the DOC is kept at 600 ℃ continuously, and the value of the third HC conversion efficiency obtained through subsequent calculation is guaranteed to be effective.
Wherein the third duration is an empirical value obtained from a large number of experiments in the early stage. In the present embodiment, the third duration is 1 hour.
And S620, controlling the post-processing system to perform oil injection for the second time, and recording the second oil injection duration.
And adjusting the oil injection quantity of the aftertreatment system to enable the temperature of the DOC to be a second set temperature, wherein the second oil injection is the post-injection oil injection of the engine. The post injection of the engine refers to injecting fuel oil with accurate metering into a combustion chamber in a crank angle of 120-180 ℃ after an exhaust top dead center after main injection. The main injection refers to a process of injecting fuel into a cylinder in a normal process of the engine.
S630, calculating a second HC injection quantity in the second fuel injection time period.
And S640, judging whether the second HC injection amount is larger than or equal to a second set HC injection amount.
If the second HC injection amount is equal to or greater than the second set HC injection amount, the third HC conversion efficiency is calculated.
It is understood that, if the second HC injection amount is smaller than the second set HC injection amount, the second fuel injection is continued until the second HC injection amount is equal to or larger than the second set HC injection amount.
Specifically, if the second HC injection amount of the second injection is equal to or greater than the second set HC injection amount, a significant temperature difference is made between the upstream temperature and the downstream temperature of the DOC during the transition of the second HC injection amount to ensure that the calculated value of the third HC conversion efficiency is valid.
Further specifically, a third upstream temperature value is measured by an upstream temperature sensor of the DOC, a third downstream temperature value is measured by a downstream temperature sensor of the DOC, and a third HC conversion efficiency is calculated according to the third upstream temperature value and the third downstream temperature value.
More specifically, the formula for calculating the third HC conversion efficiency from the third upstream temperature value and the third downstream temperature value is:
wherein, T 31 A third upstream temperature value, deg.C; t is 32 A third downstream temperature value, deg.C; t is 33 Is the third upstream theoretical temperature value, deg.C; t is 34 The third downstream theoretical temperature value, deg.C. And when the third HC conversion efficiency is calculated, the integral time period is a third set time length after the second fuel injection is finished.
And calculating the third upstream theoretical temperature value and the third downstream theoretical temperature value by the theoretical oil injection quantity of the post-processing system. The third set time period is an empirical value obtained through a large number of experiments in the early stage.
The method for calculating the third upstream theoretical temperature value and the third downstream theoretical temperature value through the theoretical oil injection quantity of the aftertreatment system belongs to the prior art, and is not described herein again.
In this embodiment, steps S620 to S640 may be performed simultaneously or sequentially.
S700, judging whether the SOF attached to the surface of the DOC is excessive according to the third HC conversion efficiency, and judging whether the DOC is aged.
Specifically, the specific steps of judging whether the SOF attached to the surface of the DOC is excessive according to the third HC conversion efficiency and judging whether the DOC is aged comprise:
it is determined whether the third HC conversion efficiency is equal to or greater than a third set HC conversion efficiency.
If the third HC conversion efficiency is equal to or greater than the third set HC conversion efficiency, the amount of SOF adhering to the DOC surface is excessive.
If the first HC conversion efficiency is less than the first set HC conversion efficiency, the DOC ages.
Therefore, whether the HC conversion efficiency of the DOC is abnormal or not can be diagnosed through the DOC diagnosis method, if the HC conversion efficiency of the DOC is abnormal, the reason that the HC conversion efficiency of the DOC is abnormal can be diagnosed through the DOC diagnosis method is caused by the excessive adhering HC on the surface of the DOC, the excessive adhering SOF on the surface of the DOC and the aging of the DOC, so that the DOC can be managed or replaced accurately, and the DOC diagnosis method is high in reliability.
The first set HC conversion efficiency is less than or equal to the second set HC conversion efficiency is less than or equal to the third set HC conversion efficiency. It is understood that as the ambient temperature of the DOC increases, the HC conversion efficiency of the DOC also increases. Therefore, the values of the first, second, and third set HC conversion efficiencies can be adjusted with the environmental temperature adaptability of the DOC.
The invention also provides an aftertreatment system, which can diagnose whether the HC conversion efficiency of the DOC is abnormal or not and the reason of the abnormal HC conversion efficiency of the DOC by applying the DOC diagnosis method, and is convenient for accurately managing or replacing the DOC.
It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention and are not intended to limit the embodiments of the present invention. Numerous obvious variations, adaptations and substitutions will occur to those skilled in the art without departing from the scope of the invention. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.
Claims (10)
1. A DOC diagnostic method, characterized by comprising:
after the DPF enters the passive regeneration, calculating first HC conversion efficiency after DOC works for a first duration;
judging whether the HC conversion efficiency of the DOC is abnormal or not according to the first HC conversion efficiency;
if the HC conversion efficiency of the DOC is abnormal, the DOC enters a first heat management mode, and second HC conversion efficiency of the DOC after the first heat management mode is calculated;
judging whether HC attached to the surface of the DOC is excessive according to the second HC conversion efficiency;
if the HC attached to the surface of the DOC is not excessive, the DOC enters a second heat management mode, and third HC conversion efficiency of the DOC after the DOC is in the second heat management mode is calculated;
and judging whether the SOF attached to the surface of the DOC is excessive according to the third HC conversion efficiency, and judging whether the DOC is aged.
2. The DOC diagnostic method of claim 1, wherein the specific steps of entering a first thermal management mode by the DOC and calculating a second HC conversion efficiency of the DOC after the first thermal management mode comprise:
adjusting the opening of a throttle valve and/or the oil injection quantity of an aftertreatment system to enable the temperature of the DOC to be a first set temperature and to last for a second duration;
controlling the post-processing system to perform oil injection for the first time, and recording the first oil injection duration;
calculating a first HC injection amount in the first injection period;
judging whether the first HC injection quantity is larger than or equal to a first set HC injection quantity;
the second HC conversion efficiency is calculated if the first HC injection amount is equal to or greater than a first set HC injection amount.
3. The DOC diagnostic method of claim 2, wherein the first set temperature is 300 ℃.
4. The DOC diagnostic method of claim 1, wherein the specific steps of entering a second thermal management mode by the DOC and calculating a third HC conversion efficiency of the DOC after the second thermal management mode comprise:
adjusting the temperature of the DOC to be a second set temperature by adjusting the opening of the throttle valve and/or the fuel injection quantity of the aftertreatment system, and continuing for a third duration;
controlling the post-processing system to perform oil injection for the second time, and recording the second oil injection duration;
calculating a second HC injection amount in the second injection period;
judging whether the second HC injection amount is larger than or equal to a second set HC injection amount;
the third HC conversion efficiency is calculated if the second HC injection amount is equal to or greater than a second set HC injection amount.
5. The DOC diagnostic method of claim 4, wherein the second set temperature is 600 ℃.
6. The DOC diagnostic method according to any one of claims 1 to 5, wherein the specific step of judging whether the HC conversion efficiency of the DOC is abnormal or not according to the first HC conversion efficiency includes:
judging whether the first HC conversion efficiency is greater than or equal to a first set HC conversion efficiency;
if the first HC conversion efficiency is larger than or equal to a first set HC conversion efficiency, the HC conversion efficiency of the DOC is normal;
and if the first HC conversion efficiency is smaller than a first set HC conversion efficiency, the HC conversion efficiency of the DOC is abnormal.
7. The DOC diagnostic method of claim 6, wherein the specific step of determining whether HC coverage of the DOC surface is excessive based on the second HC conversion efficiency comprises:
judging whether the second HC conversion efficiency is greater than or equal to a second set HC conversion efficiency;
if the second HC conversion efficiency is larger than or equal to a second set HC conversion efficiency, the HC adhered to the surface of the DOC is excessive;
if the first HC conversion efficiency is less than a first set HC conversion efficiency, the amount of HC adhered to the surface of the DOC is not excessive.
8. The DOC diagnosis method of claim 7, wherein the determining whether the SOF adhered to the surface of the DOC is excessive according to the third HC conversion efficiency and the determining whether the DOC is aged comprises:
judging whether the third HC conversion efficiency is greater than or equal to a third set HC conversion efficiency;
if the third HC conversion efficiency is larger than or equal to a third set HC conversion efficiency, the amount of SOF attached to the surface of the DOC is excessive;
and if the first HC conversion efficiency is smaller than a first set HC conversion efficiency, the DOC is aged.
9. The DOC diagnostic method of claim 8, wherein the first set HC conversion efficiency ≦ the second set HC conversion efficiency ≦ the third set HC conversion efficiency.
10. An aftertreatment system configured to implement a DOC diagnostic method according to any of claims 1-9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211034325.2A CN115163267B (en) | 2022-08-26 | 2022-08-26 | DOC diagnosis method and aftertreatment system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211034325.2A CN115163267B (en) | 2022-08-26 | 2022-08-26 | DOC diagnosis method and aftertreatment system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115163267A true CN115163267A (en) | 2022-10-11 |
| CN115163267B CN115163267B (en) | 2023-11-17 |
Family
ID=83482069
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211034325.2A Active CN115163267B (en) | 2022-08-26 | 2022-08-26 | DOC diagnosis method and aftertreatment system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115163267B (en) |
Citations (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005307745A (en) * | 2004-04-16 | 2005-11-04 | Nissan Diesel Motor Co Ltd | Exhaust emission control device |
| JP2010112220A (en) * | 2008-11-05 | 2010-05-20 | Nissan Motor Co Ltd | Catalyst diagnostic device |
| US20110296816A1 (en) * | 2009-02-05 | 2011-12-08 | Michael Parmentier | On-board vehicle diagnostic of an oxidation catalyst |
| WO2012081461A1 (en) * | 2010-12-16 | 2012-06-21 | いすゞ自動車株式会社 | Dpf system |
| CN103967569A (en) * | 2013-02-01 | 2014-08-06 | 福特环球技术公司 | Determination Of A Degree Of Aging Of An Oxidizing Catalytic Converter |
| WO2015041289A1 (en) * | 2013-09-18 | 2015-03-26 | いすゞ自動車株式会社 | Diagnostic device |
| WO2015050206A1 (en) * | 2013-10-04 | 2015-04-09 | いすゞ自動車株式会社 | Diagnostic device |
| US20150247441A1 (en) * | 2014-02-28 | 2015-09-03 | Mazda Motor Corporation | Method and system for diagnosing deterioration of exhaust emission control catalyst |
| JP2016109070A (en) * | 2014-12-09 | 2016-06-20 | いすゞ自動車株式会社 | Oxidation catalyst deterioration diagnosis device and oxidation catalyst deterioration diagnosis method |
| CN109306893A (en) * | 2018-09-27 | 2019-02-05 | 潍柴动力股份有限公司 | A kind of monitoring method, device and the diesel vehicle of diesel oxidation catalyst transfer efficiency |
| CN110630365A (en) * | 2019-09-23 | 2019-12-31 | 南京科益环保科技有限公司 | Tail gas treatment system and hydrocarbon conversion efficiency calculation method and fault diagnosis method thereof |
| CN113669143A (en) * | 2021-09-24 | 2021-11-19 | 一汽解放汽车有限公司 | Performance detection method, detection device and medium for tail gas aftertreatment system |
| CN113803143A (en) * | 2021-09-02 | 2021-12-17 | 潍柴动力股份有限公司 | DOC sulfur poisoning judgment method and control device with same |
| CN114645761A (en) * | 2022-03-31 | 2022-06-21 | 潍柴动力股份有限公司 | DOC sulfur poisoning judgment method and vehicle |
-
2022
- 2022-08-26 CN CN202211034325.2A patent/CN115163267B/en active Active
Patent Citations (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005307745A (en) * | 2004-04-16 | 2005-11-04 | Nissan Diesel Motor Co Ltd | Exhaust emission control device |
| JP2010112220A (en) * | 2008-11-05 | 2010-05-20 | Nissan Motor Co Ltd | Catalyst diagnostic device |
| US20110296816A1 (en) * | 2009-02-05 | 2011-12-08 | Michael Parmentier | On-board vehicle diagnostic of an oxidation catalyst |
| WO2012081461A1 (en) * | 2010-12-16 | 2012-06-21 | いすゞ自動車株式会社 | Dpf system |
| CN103967569A (en) * | 2013-02-01 | 2014-08-06 | 福特环球技术公司 | Determination Of A Degree Of Aging Of An Oxidizing Catalytic Converter |
| US20160222861A1 (en) * | 2013-09-18 | 2016-08-04 | Isuzu Motors Limited | Diagnostic device |
| WO2015041289A1 (en) * | 2013-09-18 | 2015-03-26 | いすゞ自動車株式会社 | Diagnostic device |
| WO2015050206A1 (en) * | 2013-10-04 | 2015-04-09 | いすゞ自動車株式会社 | Diagnostic device |
| US20150247441A1 (en) * | 2014-02-28 | 2015-09-03 | Mazda Motor Corporation | Method and system for diagnosing deterioration of exhaust emission control catalyst |
| JP2016109070A (en) * | 2014-12-09 | 2016-06-20 | いすゞ自動車株式会社 | Oxidation catalyst deterioration diagnosis device and oxidation catalyst deterioration diagnosis method |
| CN109306893A (en) * | 2018-09-27 | 2019-02-05 | 潍柴动力股份有限公司 | A kind of monitoring method, device and the diesel vehicle of diesel oxidation catalyst transfer efficiency |
| CN110630365A (en) * | 2019-09-23 | 2019-12-31 | 南京科益环保科技有限公司 | Tail gas treatment system and hydrocarbon conversion efficiency calculation method and fault diagnosis method thereof |
| CN113803143A (en) * | 2021-09-02 | 2021-12-17 | 潍柴动力股份有限公司 | DOC sulfur poisoning judgment method and control device with same |
| CN113669143A (en) * | 2021-09-24 | 2021-11-19 | 一汽解放汽车有限公司 | Performance detection method, detection device and medium for tail gas aftertreatment system |
| CN114645761A (en) * | 2022-03-31 | 2022-06-21 | 潍柴动力股份有限公司 | DOC sulfur poisoning judgment method and vehicle |
Non-Patent Citations (1)
| Title |
|---|
| 胡天相: "基于模型的柴油机氧化催化转化器故障诊断研究", 《中国优秀硕士学位论文全文数据库 (工程科技Ⅱ辑)》, pages 41 - 64 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115163267B (en) | 2023-11-17 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US7946161B2 (en) | Apparatus, system, and method for estimating particulate production | |
| US7188512B1 (en) | Apparatus, system, and method for calibrating a particulate production estimate | |
| KR100909820B1 (en) | Exhaust emission control device and internal combustion engine equipped with the exhaust emission control device and particulate filter regenerating method | |
| US9988963B2 (en) | Method for monitoring an oxidation catalysis device | |
| US7587892B2 (en) | Apparatus, system, and method for adapting a filter regeneration profile | |
| EP2394034B1 (en) | On-board vehicle diagnostic of an oxidation catalyst | |
| US8061127B2 (en) | Thermal management of diesel particulate filter regeneration events | |
| US8973430B2 (en) | Diesel particulate filter system | |
| US7631490B2 (en) | System for assisting regeneration of pollution management means | |
| EP2216521A1 (en) | Internal combustion engine exhaust gas control apparatus | |
| CN101054918B (en) | Diesel engine oxidation catalyzer (DOC) temperature-sensor rationality diagnosis | |
| US7802422B2 (en) | Method of assisting regeneration of pollution management means associated with catalyst forming means | |
| CN115163267A (en) | DOC (document management interface) diagnosis method and aftertreatment system | |
| US20080196394A1 (en) | System For Assisting Regeneration Of Pollution Management Means For Motor Vehicle Engine | |
| CN114458422B (en) | DPF active regeneration control method and system | |
| CN115324696B (en) | Smoke intensity control method and device and vehicle | |
| CN116335805A (en) | DOC performance test method for novel diesel oxidation catalytic converter | |
| US8281652B2 (en) | Method for testing the functionality of an oxidation catalyst of an internal combustion engine | |
| CN113514169B (en) | Credibility fault diagnosis method for downstream temperature sensor of SCR (selective catalytic reduction) system | |
| US20110185706A1 (en) | Method for managing the regeneration of a diesel particulate filter (dpf) in a diesel engine system | |
| CN110612387B (en) | Control method for optimizing the management of an injection device of an internal combustion engine | |
| CN115355078A (en) | DOC SOF deposition amount calculation and diagnosis method | |
| CN114722629A (en) | DPF regeneration frequent diagnosis method, device, vehicle and computer readable storage medium | |
| CN113803139A (en) | Active thermal management control method and device, vehicle and storage medium | |
| CN116877250A (en) | DPF regeneration function test system and regeneration test method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |