CN111894715A - Blockage detection method and system for SCR tail gas treatment system nozzle and vehicle - Google Patents

Blockage detection method and system for SCR tail gas treatment system nozzle and vehicle Download PDF

Info

Publication number
CN111894715A
CN111894715A CN202010794224.XA CN202010794224A CN111894715A CN 111894715 A CN111894715 A CN 111894715A CN 202010794224 A CN202010794224 A CN 202010794224A CN 111894715 A CN111894715 A CN 111894715A
Authority
CN
China
Prior art keywords
nozzle
pressure
time period
seconds
detection
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
Application number
CN202010794224.XA
Other languages
Chinese (zh)
Other versions
CN111894715B (en
Inventor
陈一平
何家明
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shanghai Xingrong Automotive Technology Co ltd
Original Assignee
Shanghai Xingrong Automotive Technology Co ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Shanghai Xingrong Automotive Technology Co ltd filed Critical Shanghai Xingrong Automotive Technology Co ltd
Priority to CN202010794224.XA priority Critical patent/CN111894715B/en
Publication of CN111894715A publication Critical patent/CN111894715A/en
Application granted granted Critical
Publication of CN111894715B publication Critical patent/CN111894715B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

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
    • F01N3/2066—Selective catalytic reduction [SCR]
    • 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
    • F01N2610/00—Adding substances to exhaust gases
    • F01N2610/02—Adding substances to exhaust gases the substance being ammonia or urea
    • 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
    • F01N2610/00—Adding substances to exhaust gases
    • F01N2610/14—Arrangements for the supply of substances, e.g. conduits
    • F01N2610/1453—Sprayers or atomisers; Arrangement thereof in the exhaust apparatus
    • 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
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
    • Y02A50/20—Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
    • 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
    • Y02T10/12—Improving ICE efficiencies
    • 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

A blockage detection method for a nozzle of an SCR tail gas treatment system comprises the following steps: s101, in the stage of reverse pumping and pressure exhaust of the SCR tail gas treatment system, detecting a liquid inlet pipe of a nozzle in a detection time period T1The pressure in the chamber, and calculating the time period T for the detection1Mean value of internal pressure
Figure DDA0002624918100000011
Wherein the detection time period T1In a time period T0Internal or with time period T0Same, the time period T0Time period t1 to t2 after nozzle opening; s102, passing the pressure average value
Figure DDA0002624918100000012
Judging the blockage condition of the nozzle: if it is
Figure DDA0002624918100000013
The nozzle is in a normal working state; if it is
Figure DDA0002624918100000014
The nozzle is in a slightly blocked state; if it is
Figure DDA0002624918100000015
The nozzle is in a severely clogged state. The invention can detect the nozzle blockage condition in real time in the reverse pumping stage, and can obtain more accurate and subdivided results compared with the existing two-state detection mode.

Description

Blockage detection method and system for SCR tail gas treatment system nozzle and vehicle
Technical Field
The invention belongs to the technical field of SCR tail gas treatment systems, and particularly relates to a blockage detection method and system for a nozzle of an SCR tail gas treatment system and a vehicle.
Background
With the continuous development and growth of automobile industry in China, the market share of commercial vehicles is also continuously promoted, and the demand and delivery of diesel engines serving as main power sources of the commercial vehicles are also increased year by year. The diesel engine has sufficient discharge capacity, excellent dynamic property and excellent fuel economy, and simultaneously has high pollution to the environment, so that the diesel engine becomes a problem to be solved urgently for vehicle emission control in China, China also starts to implement the national VI-stage emission standard of heavy diesel engines in the range of China from 7/1.2019, and manufacturers often adopt an SCR tail gas treatment system to reduce emission in order to achieve the purpose of reducing pollution in the working process of the diesel engine.
Selective Catalytic Reduction, SCR for short, is a technical principle of selectively reducing nitrogen oxides to nitrogen and water in an oxygen-rich environment by using a reducing agent under the action of a catalyst. The urea injection in SCR adopts a closed-loop injection strategy to realize the injection control of the engine in the steady-state and transient processes, and the urea injection quantity is adjusted and optimized through the operating parameters of the engine, such as the rotating speed, the fuel injection quantity, the exhaust flow, the exhaust temperature and the like.
When the SCR system works, the SCR system sequentially goes through three processes of pressure building, injection and back pumping. In the pressure building process, building pressure by a urea pump, and maintaining the urea pressure at about normal working pressure after the urea pressure is slowly increased; when the pressure of the system is built up, the system pressure is maintained at 0.5bar above and below the normal working pressure, when the system meets the injection condition, the engine control unit or the DCU sends out a urea nozzle opening instruction, when the engine finishes working, the key switch is powered off, the urea pump enters a reverse pumping stage, and in order to prevent the pipeline urea from being crystallized and blocked, the pump can suck residual urea in the pipeline and the nozzle back into the urea tank.
The nozzle of SCR system takes place to block up and can lead to the urea injection volume not enough, just also means that the oxidation-reduction reaction is incomplete in the tail gas treatment, and this one side can cause a large amount of pollutions to the environment, and on the other hand discharges that waste gas is not up to standard also can lead to the mistake of engine OBD system and restrict the maximum output torque of engine, and this not only can reduce the efficiency of vehicle operation, still can cause the influence to the security and the stability of driving, reduces driving efficiency, endangers driving safety. The existing SCR system can only carry out the binary detection of whether the nozzle is blocked.
Disclosure of Invention
In view of the above, the present invention provides a method and a system for detecting clogging of a nozzle of an SCR exhaust gas treatment system, and a vehicle.
In order to solve the technical problems, the invention adopts the following technical scheme:
a blockage detection method for a nozzle of an SCR tail gas treatment system comprises the following steps:
s101, in the stage of reverse pumping and pressure exhaust of the SCR tail gas treatment system, detecting a liquid inlet pipe of a nozzle in a detection time period T1The pressure in the chamber, and calculating the time period T for the detection1Mean value of internal pressure
Figure BDA0002624918080000021
Wherein the detection time period T1In a time period T0Internal or with time period T0Same, the time period T0Time period t1 to t2 after nozzle opening;
s102, passing the pressure average value
Figure BDA0002624918080000022
Judging the blockage condition of the nozzle:
if it is
Figure BDA0002624918080000023
The nozzle is in a normal working state;
if it is
Figure BDA0002624918080000024
The nozzle is in a slightly blocked state;
if it is
Figure BDA0002624918080000025
The nozzle is in a severely clogged state.
Wherein P1 is a preset first pressure threshold, and P2 is a preset second pressure threshold.
The t1 ═ 32 ± 2 seconds, the maximum value of t2 was 70 seconds, the P1 ═ 0.25bar, and the P2 ═ 0.45 bar.
The step S101 further includes: in the stage of the back pumping and discharging pressure of the SCR tail gas treatment system, the pressure of a liquid inlet pipe of the nozzle in a time period of 30 seconds to 40 seconds after the nozzle is opened is detected, and the average value of the pressure in the time period of 30 seconds to 40 seconds is calculated
Figure BDA0002624918080000026
This scheme still relates to a jam detecting system of SCR tail gas treatment system nozzle, including the storage module, the storage module includes many instructions loaded and executed by the treater:
s101, in the stage of reverse pumping and pressure exhaust of the SCR tail gas treatment system, detecting a liquid inlet pipe of a nozzle in a detection time period T1The pressure in the chamber, and calculating the time period T for the detection1Mean value of internal pressure
Figure BDA0002624918080000027
Wherein the detection time period T1In a time period T0Internal or with time period T0Same, the time period T0Time period t1 to t2 after nozzle opening;
s102, passing the pressure average value
Figure BDA0002624918080000031
Judging the blockage condition of the nozzle:
if it is
Figure BDA0002624918080000032
The nozzle is in a normal working state;
if it is
Figure BDA0002624918080000033
The nozzle is in a slightly blocked state;
if it is
Figure BDA0002624918080000034
The nozzle is in a severely clogged state.
Wherein P1 is a preset first pressure threshold, and P2 is a preset second pressure threshold.
The t1 ═ 32 ± 2 seconds, the maximum value of t2 was 70 seconds, the P1 ═ 0.25bar, and the P2 ═ 0.45 bar.
The step S101 further includes: in the stage of the back pumping and discharging pressure of the SCR tail gas treatment system, the pressure of a liquid inlet pipe of the nozzle in a time period of 30 seconds to 40 seconds after the nozzle is opened is detected, and the average value of the pressure in the time period of 30 seconds to 40 seconds is calculated
Figure BDA0002624918080000035
The present disclosure also relates to a vehicle having a blockage detection system for an SCR exhaust treatment system nozzle, the system comprising a memory module including a plurality of instructions loaded and executed by a processor:
s101, in the stage of reverse pumping and pressure exhaust of the SCR tail gas treatment system, detecting a liquid inlet pipe of a nozzle in a detection time period T1The pressure in the chamber, and calculating the time period T for the detection1Mean value of internal pressure
Figure BDA0002624918080000036
Wherein the detection time period T1In a time period T0Internal or with time period T0Same, the time period T0Time period t1 to t2 after nozzle opening;
s102, passing the pressure average value
Figure BDA0002624918080000037
Judging the blockage condition of the nozzle:
if it is
Figure BDA0002624918080000038
The nozzle is in a normal working state;
if it is
Figure BDA0002624918080000039
The nozzle is in a slightly blocked state;
if it is
Figure BDA00026249180800000310
The nozzle is in a severely clogged state.
Wherein P1 is a preset first pressure threshold, and P2 is a preset second pressure threshold.
The t1 ═ 32 ± 2 seconds, the maximum value of t2 was 70 seconds, the P1 ═ 0.25bar, and the P2 ═ 0.45 bar.
The step S101 further includes: in the stage of the back pumping and discharging pressure of the SCR tail gas treatment system, the pressure of a liquid inlet pipe of the nozzle in a time period of 30 seconds to 40 seconds after the nozzle is opened is detected, and the average value of the pressure in the time period of 30 seconds to 40 seconds is calculated
Figure BDA00026249180800000311
The invention can detect the nozzle blockage condition in real time in the reverse pumping stage, and can obtain more accurate and subdivided results compared with the existing two-state detection mode.
Drawings
The invention is described in detail below with reference to the following figures and detailed description:
FIG. 1 is a flow chart of the present invention;
FIG. 2 is a schematic view of the internal structure of a urea pump;
FIG. 3 is a graph showing pressure changes in three sub-processes of the reverse pumping process of the nozzle inlet pipe when the nozzle is in a good condition;
FIG. 4 is a graph comparing pressure curves of the inlet pipe of the nozzle during the third sub-process of the reverse pumping process under the conditions of good condition and severe blockage of the nozzle;
FIG. 5 is a pressure average value of the present invention
Figure BDA0002624918080000041
A linear relationship with the degree of clogging.
Detailed Description
As shown in fig. 1, a method for detecting blockage of a nozzle of an SCR exhaust gas treatment system includes:
s101, in the stage of reverse pumping and pressure exhaust of the SCR tail gas treatment system, detecting a liquid inlet pipe of a nozzle in a detection time period T1The pressure in the chamber, and calculating the time period T for the detection1Mean value of internal pressure
Figure BDA0002624918080000042
Wherein the time period T is detected1In a time period T0Internal or with time period T0Same, time period T0The time period t1 to t2 after the nozzle is opened.
S102, passing pressure average value
Figure BDA0002624918080000043
Judging the blockage condition of the nozzle:
if it is
Figure BDA0002624918080000044
The nozzle is in a normal working state;
if it is
Figure BDA0002624918080000045
The nozzle is in a slightly blocked state;
if it is
Figure BDA0002624918080000046
The nozzle is in a severely clogged state.
Wherein P1 is a preset first pressure threshold, P2 is a preset second pressureForce thresholds, two thresholds detecting a time period T after nozzle opening by a SCR system that detects in advance that a plurality of nozzles are good and a SCR system that has a plurality of nozzles that are heavily clogged1The duty ratio of the internal reverse pump is obtained by respectively calculating the average value.
The invention utilizes the pressure change condition of the liquid inlet pipe of the nozzle to detect the blockage condition of the nozzle in the pressure discharge stage of the back-pumping process of the SCR tail gas treatment system.
Referring to fig. 2, at the beginning of the back-pumping process, the main pump M2 is always in the closed state, and the back-pumping pump M1 cooperates with the nozzle to back-pump and recycle the residual urea solution in the pipeline and the nozzle, and a total of three sub-processes are performed, as shown in table 1:
Figure BDA0002624918080000051
TABLE 1
The first process is as follows: natural pressure relief
The nozzle is closed, the reverse pumping pump M1 and the main pump M2 are both in a closed state, the urea solution naturally falls back to the urea box, and the pressure of the liquid inlet pipe of the nozzle naturally falls back.
And a second process: pump reverse pump
When the pressure of the nozzle liquid inlet pipe naturally falls back to a certain value, the back-suction pump M1 starts to work, the pressure of the nozzle liquid inlet pipe continuously drops, when the pressure drops to a certain limit value, the nozzle is opened, and then the process III is carried out.
The third process: inverted pumping injection pipe (inverted pumping pressure stage)
The reverse pump M1 continuously pumps the residual urea solution in the injection pipeline of the nozzle, and after the pressure of the liquid inlet pipe of the nozzle rises suddenly, different pressure change conditions exist according to different nozzle blockage states:
if the injector nozzle works normally and is not blocked, the pressure of the liquid inlet pipe of the nozzle is gradually increased to 0 (relative pressure) after the liquid inlet pipe of the nozzle is slightly raised.
If any one or more nozzles of the nozzle are blocked, the pressure of the liquid inlet pipe of the nozzle falls rapidly after a short rise and is kept low all the time and even continuously falls.
Taking a nozzle in a good state as an example, the pressure change trend of the liquid inlet pipe of the nozzle in the first, the second and the third processes of the back pumping process is shown in fig. 3, the x axis is time (second), the y axis is pressure (hectopa), and as the nozzle works well, when the nozzle is opened, the liquid inlet pipe of the nozzle is communicated with air, the relative pressure is close to 0, and the detection result of the pressure sensor is 0 (relative pressure).
As shown in fig. 4, it can be seen that the nozzle continues to work due to the back-suction pump under severe blockage, the pressure in the liquid inlet pipe of the nozzle will generate negative pressure due to suction force, and the nozzle which works well is connected with the external atmosphere, and the pressure after rising will be kept at about 0 (relative pressure).
Therefore, we can detect the time period T1Mean value of pressure in internal nozzle inlet pipe
Figure BDA0002624918080000061
Comparing with two threshold values obtained by experiment, judging the blocking state of the nozzle, see step S102.
The method can be used for detecting the nozzle blockage condition in real time in the reverse pumping stage, and compared with the existing two-state detection mode, the method can obtain more accurate and subdivided results so as to inform a driver of the results in time and upload the results to the cloud end for auxiliary analysis by the cloud end, thereby achieving quick response to the nozzle blockage fault.
It should be noted that, as can be seen from fig. 4, after the nozzle is opened, the pressure in the nozzle inlet pipe in the blocked state is lower than the pressure in the nozzle inlet pipe in the normal state throughout the entire period. The sequence of back pumping the injection tubes is as follows: when being full of liquid in the pipeline, firstly, the pure liquid of taking out, go to the mixture of taking out liquid and air again, extract the air at last, when taking out the pure liquid backward, whether the nozzle blocks up does not influence nozzle feed liquor intraductal pressure greatly, therefore the difference is not obvious, nozzle feed liquor intraductal pressure fluctuation may be unstable when taking out the liquid mixture backward, this also does not do benefit to the measurement, only when only taking out the air backward, under the certain circumstances of pump duty cycle that takes out backward, whether the nozzle blocks up influences the intraductal pressure of nozzle feed liquor huge, data of drawing this moment can make the difference show most, and the accuracy is improved.
By testing the nozzles with different degrees of blockage, urea solution in the nozzle liquid inlet pipe of the nozzle with different degrees of blockage can be completely pumped at t1 (32 +/-2 seconds) after the nozzle is opened in the stage of back pumping and discharging pressure, so that the pressure in the nozzle liquid inlet pipe only remains air pressure, and the accuracy of data extraction is high from the moment.
In this embodiment, the maximum value of t2 is 70 seconds, ensuring that the test is valid before the end of the back-pumping of the injection tube. The detection time period T can be set1Set to 20 seconds to 30 seconds, 20 seconds to 40 seconds, or 30 seconds to 70 seconds, and also set to 30 seconds to 50 seconds, or 35 seconds to 60 seconds, and of course, may be set to 50 seconds to 70 seconds.
In this example, P1 ═ 0.25bar and P2 ═ 0.45 bar.
The pressure of the nozzle liquid inlet pipe is collected through the pressure sensor and then curve simulation is carried out, fitting analysis and comparison are carried out on different pressure curves obtained under different degrees of blockage conditions in the test, linear correlation is carried out on the obtained residual error and the actual damage degree, and finally the conclusion is obtained: the average pressure of the nozzle liquid inlet pipe 30-40S after the pressure discharge stage is started (i.e. after the nozzle is opened) can be used as the most comprehensive performance index of the nozzle, and has typical difference and expression forms under different blockage conditions as parameters, and is the most suitable technical parameter for being used as a judgment standard, namely, the most suitable technical parameter is the best fit when the judgment is compared with the threshold value, so in the step S101, the pressure of the nozzle liquid inlet pipe in the time period of 30 seconds to 40 seconds after the nozzle is opened is preferably detected, and the average pressure value in the time period of 30 seconds to 40 seconds is calculated
Figure BDA0002624918080000071
See fig. 3 and 4.
When in use
Figure BDA0002624918080000072
The nozzle is in a normal operating condition.
If it is
Figure BDA0002624918080000073
The nozzle is in a slightly clogged state.
If it is
Figure BDA0002624918080000074
The nozzle is in a severely clogged state.
Preferably, as shown in FIG. 5, the present invention can pass the pressure average value
Figure BDA0002624918080000075
And the linear relation with the blockage degree, and scoring (such as percentile system, 60-point passing or ABC rating) for more concrete and visual blockage conditions.
This scheme still relates to a jam detecting system of SCR tail gas treatment system nozzle, including the storage module, the storage module includes many instructions of being loaded and carrying out by the treater, refer to fig. 1:
s101, in the stage of reverse pumping and pressure exhaust of the SCR tail gas treatment system, detecting a liquid inlet pipe of a nozzle in a detection time period T1The pressure in the chamber, and calculating the time period T for the detection1Mean value of internal pressure
Figure BDA0002624918080000076
Wherein the time period T is detected1In a time period T0Internal or with time period T0Same, time period T0The time period t1 to t2 after the nozzle is opened.
S102, passing pressure average value
Figure BDA0002624918080000077
Judging the blockage condition of the nozzle:
if it is
Figure BDA0002624918080000078
The nozzle is in a normal working state;
if it is
Figure BDA0002624918080000079
The nozzle is in a slightly blocked state;
if it is
Figure BDA00026249180800000710
The nozzle is in a severely clogged state.
Wherein P1 is a preset first pressure threshold, P2 is a preset second pressure threshold, and the two thresholds are detected for a time period T after the nozzles are opened by an SCR system which detects the completeness of the nozzles and an SCR system which detects the serious blockage of the nozzles in advance1The duty ratio of the internal reverse pump is obtained by respectively calculating the average value.
The invention utilizes the pressure change condition of the liquid inlet pipe of the nozzle to detect the blockage condition of the nozzle in the pressure discharge stage of the back-pumping process of the SCR tail gas treatment system.
Referring to fig. 2, at the beginning of the back-pumping process, the main pump M2 is always in the closed state, and the back-pumping pump M1 cooperates with the nozzle to back-pump and recycle the residual urea solution in the pipeline and the nozzle, and a total of three sub-processes are performed, as shown in table 1:
Figure BDA0002624918080000081
TABLE 1
The first process is as follows: natural pressure relief
The nozzle is closed, the reverse pumping pump M1 and the main pump M2 are both in a closed state, the urea solution naturally falls back to the urea box, and the pressure of the liquid inlet pipe of the nozzle naturally falls back.
And a second process: pump reverse pump
When the pressure of the nozzle liquid inlet pipe naturally falls back to a certain value, the back-suction pump M1 starts to work, the pressure of the nozzle liquid inlet pipe continuously drops, when the pressure drops to a certain limit value, the nozzle is opened, and then the process III is carried out.
The third process: inverted pumping injection pipe (inverted pumping pressure stage)
The reverse pump M1 continuously pumps the residual urea solution in the injection pipeline of the nozzle, and after the pressure of the liquid inlet pipe of the nozzle rises suddenly, different pressure change conditions exist according to different nozzle blockage states:
if the injector nozzle works normally and is not blocked, the pressure of the liquid inlet pipe of the nozzle is gradually increased to 0 (relative pressure) after the liquid inlet pipe of the nozzle is slightly raised.
If any one or more nozzles of the nozzle are blocked, the pressure of the liquid inlet pipe of the nozzle falls rapidly after a short rise and is kept low all the time and even continuously falls.
Taking a nozzle in a good state as an example, the pressure change trend of the liquid inlet pipe of the nozzle in the first, the second and the third processes of the back pumping process is shown in fig. 3, the x axis is time (second), the y axis is pressure (hectopa), and as the nozzle works well, when the nozzle is opened, the liquid inlet pipe of the nozzle is communicated with air, the relative pressure is close to 0, and the detection result of the pressure sensor is 0 (relative pressure).
As shown in fig. 4, it can be seen that the nozzle continues to work due to the back-suction pump under severe blockage, the pressure in the liquid inlet pipe of the nozzle will generate negative pressure due to suction force, and the nozzle which works well is connected with the external atmosphere, and the pressure after rising will be kept at about 0 (relative pressure).
Therefore, we can detect the time period T1Mean value of pressure in internal nozzle inlet pipe
Figure BDA0002624918080000082
Comparing with two threshold values obtained by experiment, judging the blocking state of the nozzle, see step S102.
The method can be used for detecting the nozzle blockage condition in real time in the reverse pumping stage, and compared with the existing two-state detection mode, the method can obtain more accurate and subdivided results so as to inform a driver of the results in time and upload the results to the cloud end for auxiliary analysis by the cloud end, thereby achieving quick response to the nozzle blockage fault.
It should be noted that, as can be seen from fig. 4, after the nozzle is opened, the pressure in the nozzle inlet pipe in the blocked state is lower than the pressure in the nozzle inlet pipe in the normal state throughout the entire period. The sequence of back pumping the injection tubes is as follows: when being full of liquid in the pipeline, firstly, the pure liquid of taking out, go to the mixture of taking out liquid and air again, extract the air at last, when taking out the pure liquid backward, whether the nozzle blocks up does not influence nozzle feed liquor intraductal pressure greatly, therefore the difference is not obvious, nozzle feed liquor intraductal pressure fluctuation may be unstable when taking out the liquid mixture backward, this also does not do benefit to the measurement, only when only taking out the air backward, under the certain circumstances of pump duty cycle that takes out backward, whether the nozzle blocks up influences the intraductal pressure of nozzle feed liquor huge, data of drawing this moment can make the difference show most, and the accuracy is improved.
By testing the nozzles with different degrees of blockage, urea solution in the nozzle liquid inlet pipe of the nozzle with different degrees of blockage can be completely pumped at t1 (32 +/-2 seconds) after the nozzle is opened in the stage of back pumping and discharging pressure, so that the pressure in the nozzle liquid inlet pipe only remains air pressure, and the accuracy of data extraction is high from the moment.
In this embodiment, the maximum value of t2 is 70 seconds, ensuring that the test is valid before the end of the back-pumping of the injection tube. The detection time period T can be set1Set to 20 seconds to 30 seconds, 20 seconds to 40 seconds, or 30 seconds to 70 seconds, and also set to 30 seconds to 50 seconds, or 35 seconds to 60 seconds, and of course, may be set to 50 seconds to 70 seconds.
In this example, P1 ═ 0.25bar and P2 ═ 0.45 bar.
The pressure of the nozzle liquid inlet pipe is collected through the pressure sensor and then curve simulation is carried out, fitting analysis and comparison are carried out on different pressure curves obtained under different degrees of blockage conditions in the test, linear correlation is carried out on the obtained residual error and the actual damage degree, and finally the conclusion is obtained: the average pressure of the nozzle liquid inlet pipe 30-40S after the pressure discharge stage is started (i.e. after the nozzle is opened) can be used as the most comprehensive performance index of the nozzle, and has typical difference and expression forms under different blockage conditions as parameters, and is the most suitable technical parameter for being used as a judgment standard, namely, the most suitable technical parameter is the best fit when the judgment is compared with the threshold value, so in the step S101, the pressure of the nozzle liquid inlet pipe in the time period of 30 seconds to 40 seconds after the nozzle is opened is preferably detected, and the average pressure value in the time period of 30 seconds to 40 seconds is calculated
Figure BDA0002624918080000101
See fig. 3 and 4.
When in use
Figure BDA0002624918080000102
The nozzle is in a normal operating condition.
If it is
Figure BDA0002624918080000103
The nozzle is in a slightly clogged state.
If it is
Figure BDA0002624918080000104
The nozzle is in a severely clogged state.
Preferably, as shown in FIG. 5, the present invention can pass the pressure average value
Figure BDA0002624918080000105
And the linear relation with the blockage degree, and scoring (such as percentile system, 60-point passing or ABC rating) for more concrete and visual blockage conditions.
The invention also relates to a vehicle having a blockage detection system for a nozzle of an SCR exhaust gas treatment system, the system comprising a memory module comprising a plurality of instructions loaded and executed by a processor, see fig. 1:
s101, in the stage of reverse pumping and pressure exhaust of the SCR tail gas treatment system, detecting a liquid inlet pipe of a nozzle in a detection time period T1The pressure in the chamber, and calculating the time period T for the detection1Mean value of internal pressure
Figure BDA0002624918080000106
Wherein the time period T is detected1In a time period T0Internal or with time period T0Same, time period T0The time period t1 to t2 after the nozzle is opened.
S102, passing pressure average value
Figure BDA0002624918080000107
Judging nozzle blockagePlug condition:
if it is
Figure BDA0002624918080000108
The nozzle is in a normal working state;
if it is
Figure BDA0002624918080000109
The nozzle is in a slightly blocked state;
if it is
Figure BDA00026249180800001010
The nozzle is in a severely clogged state.
Wherein P1 is a preset first pressure threshold, P2 is a preset second pressure threshold, and the two thresholds are detected for a time period T after the nozzles are opened by an SCR system which detects the completeness of the nozzles and an SCR system which detects the serious blockage of the nozzles in advance1The duty ratio of the internal reverse pump is obtained by respectively calculating the average value.
The invention utilizes the pressure change condition of the liquid inlet pipe of the nozzle to detect the blockage condition of the nozzle in the pressure discharge stage of the back-pumping process of the SCR tail gas treatment system.
Referring to fig. 2, at the beginning of the back-pumping process, the main pump M2 is always in the closed state, and the back-pumping pump M1 cooperates with the nozzle to back-pump and recycle the residual urea solution in the pipeline and the nozzle, and a total of three sub-processes are performed, as shown in table 1:
Figure BDA0002624918080000111
TABLE 1
The first process is as follows: natural pressure relief
The nozzle is closed, the reverse pumping pump M1 and the main pump M2 are both in a closed state, the urea solution naturally falls back to the urea box, and the pressure of the liquid inlet pipe of the nozzle naturally falls back.
And a second process: pump reverse pump
When the pressure of the nozzle liquid inlet pipe naturally falls back to a certain value, the back-suction pump M1 starts to work, the pressure of the nozzle liquid inlet pipe continuously drops, when the pressure drops to a certain limit value, the nozzle is opened, and then the process III is carried out.
The third process: inverted pumping injection pipe (inverted pumping pressure stage)
The reverse pump M1 continuously pumps the residual urea solution in the injection pipeline of the nozzle, and after the pressure of the liquid inlet pipe of the nozzle rises suddenly, different pressure change conditions exist according to different nozzle blockage states:
if the injector nozzle works normally and is not blocked, the pressure of the liquid inlet pipe of the nozzle is gradually increased to 0 (relative pressure) after the liquid inlet pipe of the nozzle is slightly raised.
If any one or more nozzles of the nozzle are blocked, the pressure of the liquid inlet pipe of the nozzle falls rapidly after a short rise and is kept low all the time and even continuously falls.
Taking a nozzle in a good state as an example, the pressure change trend of the liquid inlet pipe of the nozzle in the first, the second and the third processes of the back pumping process is shown in fig. 3, the x axis is time (second), the y axis is pressure (hectopa), and as the nozzle works well, when the nozzle is opened, the liquid inlet pipe of the nozzle is communicated with air, the relative pressure is close to 0, and the detection result of the pressure sensor is 0 (relative pressure).
As shown in fig. 4, it can be seen that the nozzle continues to work due to the back-suction pump under severe blockage, the pressure in the liquid inlet pipe of the nozzle will generate negative pressure due to suction force, and the nozzle which works well is connected with the external atmosphere, and the pressure after rising will be kept at about 0 (relative pressure).
Therefore, we can detect the time period T1Mean value of pressure in internal nozzle inlet pipe
Figure BDA0002624918080000112
Comparing with two threshold values obtained by experiment, judging the blocking state of the nozzle, see step S102.
The method can be used for detecting the nozzle blockage condition in real time in the reverse pumping stage, and compared with the existing two-state detection mode, the method can obtain more accurate and subdivided results so as to inform a driver of the results in time and upload the results to the cloud end for auxiliary analysis by the cloud end, thereby achieving quick response to the nozzle blockage fault.
It should be noted that, as can be seen from fig. 4, after the nozzle is opened, the pressure in the nozzle inlet pipe in the blocked state is lower than the pressure in the nozzle inlet pipe in the normal state throughout the entire period. The sequence of back pumping the injection tubes is as follows: when being full of liquid in the pipeline, firstly, the pure liquid of taking out, go to the mixture of taking out liquid and air again, extract the air at last, when taking out the pure liquid backward, whether the nozzle blocks up does not influence nozzle feed liquor intraductal pressure greatly, therefore the difference is not obvious, nozzle feed liquor intraductal pressure fluctuation may be unstable when taking out the liquid mixture backward, this also does not do benefit to the measurement, only when only taking out the air backward, under the certain circumstances of pump duty cycle that takes out backward, whether the nozzle blocks up influences the intraductal pressure of nozzle feed liquor huge, data of drawing this moment can make the difference show most, and the accuracy is improved.
By testing the nozzles with different degrees of blockage, urea solution in the nozzle liquid inlet pipe of the nozzle with different degrees of blockage can be completely pumped at t1 (32 +/-2 seconds) after the nozzle is opened in the stage of back pumping and discharging pressure, so that the pressure in the nozzle liquid inlet pipe only remains air pressure, and the accuracy of data extraction is high from the moment.
In this embodiment, the maximum value of t2 is 70 seconds, ensuring that the test is valid before the end of the back-pumping of the injection tube. The detection time period T can be set1Set to 20 seconds to 30 seconds, 20 seconds to 40 seconds, or 30 seconds to 70 seconds, and also set to 30 seconds to 50 seconds, or 35 seconds to 60 seconds, and of course, may be set to 50 seconds to 70 seconds.
In this example, P1 ═ 0.25bar and P2 ═ 0.45 bar.
The pressure of the nozzle liquid inlet pipe is collected through the pressure sensor and then curve simulation is carried out, fitting analysis and comparison are carried out on different pressure curves obtained under different degrees of blockage conditions in the test, linear correlation is carried out on the obtained residual error and the actual damage degree, and finally the conclusion is obtained: the average pressure of the liquid inlet pipe of the nozzle of 30-40s after the pressure discharge stage is started (namely after the nozzle is opened) can be used as the comprehensive performance index of the nozzle and can be used as a parameter to block the nozzle at different degreesThe typical difference and expression form of the plug condition is the most suitable technical parameter for being used as the judgment standard, i.e. the best fit degree is obtained when the comparison is carried out with the threshold value, therefore, in step S101, preferably, the pressure of the nozzle liquid inlet pipe in the 30-40 second time period after the nozzle is opened is detected, and the pressure average value in the 30-40 second time period is calculated
Figure BDA0002624918080000131
See fig. 3 and 4.
When in use
Figure BDA0002624918080000132
The nozzle is in a normal operating condition.
If it is
Figure BDA0002624918080000133
The nozzle is in a slightly clogged state.
If it is
Figure BDA0002624918080000134
The nozzle is in a severely clogged state.
Preferably, as shown in FIG. 5, the present invention can pass the pressure average value
Figure BDA0002624918080000135
And the linear relation with the blockage degree, and scoring (such as percentile system, 60-point passing or ABC rating) for more concrete and visual blockage conditions.
However, those skilled in the art should realize that the above embodiments are illustrative only and not limiting to the present invention, and that changes and modifications to the above described embodiments are intended to fall within the scope of the appended claims, provided they fall within the true spirit of the present invention.

Claims (9)

1. A blockage detection method for a nozzle of an SCR tail gas treatment system is characterized by comprising the following steps:
s101, back pumping and discharging in SCR tail gas treatment systemPressing stage, detecting the liquid inlet pipe of the nozzle in the detection time period T1The pressure in the chamber, and calculating the time period T for the detection1Mean value of internal pressure
Figure FDA0002624918070000011
Wherein the detection time period T1In a time period T0Internal or with time period T0Same, the time period T0Time period t1 to t2 after nozzle opening;
s102, passing the pressure average value
Figure FDA0002624918070000012
Judging the blockage condition of the nozzle:
if it is
Figure FDA0002624918070000013
The nozzle is in a normal working state;
if it is
Figure FDA0002624918070000014
The nozzle is in a slightly blocked state;
if it is
Figure FDA0002624918070000015
The nozzle is in a severely clogged state.
Wherein P1 is a preset first pressure threshold, and P2 is a preset second pressure threshold.
2. The method of claim 1, wherein t1 is 32 ± 2 seconds, the maximum t2 is 70 seconds, P1 is-0.25 bar, and P2 is-0.45 bar.
3. The method of claim 1, wherein the step S101 further comprises: reverse pumping and exhausting pressure step in SCR tail gas treatment systemDetecting the pressure of the liquid inlet pipe of the nozzle in a period of 30 seconds to 40 seconds after the nozzle is opened, and calculating the average value of the pressure in the period of 30 seconds to 40 seconds
Figure FDA0002624918070000016
4. A blockage detection system for an SCR exhaust treatment system nozzle, comprising a memory module including a plurality of instructions loaded and executed by a processor:
s101, in the stage of reverse pumping and pressure exhaust of the SCR tail gas treatment system, detecting a liquid inlet pipe of a nozzle in a detection time period T1The pressure in the chamber, and calculating the time period T for the detection1Mean value of internal pressure
Figure FDA0002624918070000017
Wherein the detection time period T1In a time period T0Internal or with time period T0Same, the time period T0Time period t1 to t2 after nozzle opening;
s102, passing the pressure average value
Figure FDA0002624918070000018
Judging the blockage condition of the nozzle:
if it is
Figure FDA0002624918070000021
The nozzle is in a normal working state;
if it is
Figure FDA0002624918070000022
The nozzle is in a slightly blocked state;
if it is
Figure FDA0002624918070000023
The nozzle is in a severely clogged state.
Wherein P1 is a preset first pressure threshold, and P2 is a preset second pressure threshold.
5. The system of claim 4, wherein t1 is 32 ± 2 seconds, the maximum t2 is 70 seconds, the maximum P1 is-0.25 bar, and the maximum P2 is-0.45 bar.
6. The system of claim 5, wherein the step S101 further comprises: in the stage of the back pumping and discharging pressure of the SCR tail gas treatment system, the pressure of a liquid inlet pipe of the nozzle in a time period of 30 seconds to 40 seconds after the nozzle is opened is detected, and the average value of the pressure in the time period of 30 seconds to 40 seconds is calculated
Figure FDA0002624918070000024
7. A vehicle characterized by a blockage detection system having an SCR exhaust treatment system nozzle, the system comprising a memory module including a plurality of instructions loaded and executed by a processor:
s101, in the stage of reverse pumping and pressure exhaust of the SCR tail gas treatment system, detecting a liquid inlet pipe of a nozzle in a detection time period T1The pressure in the chamber, and calculating the time period T for the detection1Mean value of internal pressure
Figure FDA0002624918070000025
Wherein the detection time period T1In a time period T0Internal or with time period T0Same, the time period T0Time period t1 to t2 after nozzle opening;
s102, passing the pressure average value
Figure FDA0002624918070000026
Judging the blockage condition of the nozzle:
if it is
Figure FDA0002624918070000027
The nozzle is in a normal working state;
if it is
Figure FDA0002624918070000028
The nozzle is in a slightly blocked state;
if it is
Figure FDA0002624918070000029
The nozzle is in a severely clogged state.
Wherein P1 is a preset first pressure threshold, and P2 is a preset second pressure threshold.
8. A vehicle according to claim 7, characterized in that t 1-32 ± 2 seconds, the maximum value of t2 is 70 seconds, P1-0.25 bar and P2-0.45 bar.
9. The vehicle according to claim 8, wherein the step S101 further comprises: in the stage of the back pumping and discharging pressure of the SCR tail gas treatment system, the pressure of a liquid inlet pipe of the nozzle in a time period of 30 seconds to 40 seconds after the nozzle is opened is detected, and the average value of the pressure in the time period of 30 seconds to 40 seconds is calculated
Figure FDA0002624918070000031
CN202010794224.XA 2020-08-10 2020-08-10 Blockage detection method and system for SCR tail gas treatment system nozzle and vehicle Active CN111894715B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010794224.XA CN111894715B (en) 2020-08-10 2020-08-10 Blockage detection method and system for SCR tail gas treatment system nozzle and vehicle

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010794224.XA CN111894715B (en) 2020-08-10 2020-08-10 Blockage detection method and system for SCR tail gas treatment system nozzle and vehicle

Publications (2)

Publication Number Publication Date
CN111894715A true CN111894715A (en) 2020-11-06
CN111894715B CN111894715B (en) 2021-12-31

Family

ID=73246339

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010794224.XA Active CN111894715B (en) 2020-08-10 2020-08-10 Blockage detection method and system for SCR tail gas treatment system nozzle and vehicle

Country Status (1)

Country Link
CN (1) CN111894715B (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112648058A (en) * 2021-01-04 2021-04-13 东风汽车股份有限公司 Urea injection device of engine SCR system and fault diagnosis method thereof
CN113250797A (en) * 2021-04-29 2021-08-13 广西玉柴机器股份有限公司 Method and device for diagnosing urea solution consumption deviation process
CN115415501A (en) * 2022-09-19 2022-12-02 华域皮尔博格有色零部件(上海)有限公司 Lubricant spraying device

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008121588A (en) * 2006-11-14 2008-05-29 Denso Corp Diagnostic device for internal combustion engine
CN102052513A (en) * 2009-10-30 2011-05-11 博世株式会社 Reducing agent injection valve abnormality detection device and abnormality detection method, and internal combustion engine exhaust gas purification system
CN102052133A (en) * 2009-11-06 2011-05-11 博世株式会社 Reducing agent injection valve abnormality detection device and abnormality detection method
CN102966416A (en) * 2011-08-30 2013-03-13 现代自动车株式会社 Verfahren zum vermeiden einer verstopfung einer harnstoff-einspritzdse an einem scr-system
US20130180323A1 (en) * 2010-06-23 2013-07-18 Inergy Automotive Systems Research (Societe Anonyme) Method for monitoring an scr system
US20140305100A1 (en) * 2013-04-15 2014-10-16 Kia Motors Corporation Method for preventing clogging of urea injection nozzle of scr system
CN107060969A (en) * 2016-12-26 2017-08-18 潍柴动力空气净化科技有限公司 SCR spraying systems test device and method
CN109681304A (en) * 2018-12-25 2019-04-26 上海星融汽车科技有限公司 A kind of SCR system urea nozzle blocking recognition methods

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008121588A (en) * 2006-11-14 2008-05-29 Denso Corp Diagnostic device for internal combustion engine
CN102052513A (en) * 2009-10-30 2011-05-11 博世株式会社 Reducing agent injection valve abnormality detection device and abnormality detection method, and internal combustion engine exhaust gas purification system
CN102052133A (en) * 2009-11-06 2011-05-11 博世株式会社 Reducing agent injection valve abnormality detection device and abnormality detection method
US20130180323A1 (en) * 2010-06-23 2013-07-18 Inergy Automotive Systems Research (Societe Anonyme) Method for monitoring an scr system
CN102966416A (en) * 2011-08-30 2013-03-13 现代自动车株式会社 Verfahren zum vermeiden einer verstopfung einer harnstoff-einspritzdse an einem scr-system
US20140305100A1 (en) * 2013-04-15 2014-10-16 Kia Motors Corporation Method for preventing clogging of urea injection nozzle of scr system
CN107060969A (en) * 2016-12-26 2017-08-18 潍柴动力空气净化科技有限公司 SCR spraying systems test device and method
CN109681304A (en) * 2018-12-25 2019-04-26 上海星融汽车科技有限公司 A kind of SCR system urea nozzle blocking recognition methods

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112648058A (en) * 2021-01-04 2021-04-13 东风汽车股份有限公司 Urea injection device of engine SCR system and fault diagnosis method thereof
CN112648058B (en) * 2021-01-04 2022-02-18 东风汽车股份有限公司 Urea injection device of engine SCR system and fault diagnosis method thereof
CN113250797A (en) * 2021-04-29 2021-08-13 广西玉柴机器股份有限公司 Method and device for diagnosing urea solution consumption deviation process
CN115415501A (en) * 2022-09-19 2022-12-02 华域皮尔博格有色零部件(上海)有限公司 Lubricant spraying device

Also Published As

Publication number Publication date
CN111894715B (en) 2021-12-31

Similar Documents

Publication Publication Date Title
CN111894715B (en) Blockage detection method and system for SCR tail gas treatment system nozzle and vehicle
CN102128651B (en) Injector flow measurement for fuel cell applications
CN1863988B (en) Exhaust emission purification device and exhaust emission purification method
US8387366B2 (en) Reducing agent injection valve abnormality detection device and abnormality detection method, and internal combustion engine exhaust gas purification system
CN110649287B (en) Fuel cell engine system, gas supply system thereof and control method
CN103221649B (en) To the diagnosis of the hydrocarbon injection for filter regeneration
CN111878205A (en) Method for identifying leakage of urea pressure pipe of aftertreatment system
EP1688599A1 (en) Engine controller and engine operating method
EP2128396A1 (en) Breakdown diagnosing device and breakdown diagnosing method of nox sensor
US9683473B2 (en) Exhaust gas control apparatus
AU2021236547A1 (en) Failure detection method for SCR urea injection devices
EP3073083B1 (en) Exhaust gas control apparatus
CN111894714A (en) Blockage detection method and system for liquid inlet filter of SCR system and vehicle
CN204113406U (en) Vehicle tail gas treatment device
CN100416054C (en) Engine controller and engine operating method
CN112648058B (en) Urea injection device of engine SCR system and fault diagnosis method thereof
CN112282904B (en) Method for detecting voltage build-up fault of SCR system
CN111828152A (en) Method for identifying filter element blockage of aftertreatment system
CN113236405B (en) Fault diagnosis method and device for urea injection system
CN209892299U (en) System for regenerating particle trap by taking methanol as external energy
WO2022002041A1 (en) Method and device for detecting a leakage rate of a solid oxide fuel cell system
CN201089795Y (en) Reversing arrangement having shut unclosed prompt facility
CN114039071A (en) Hydrogen pipeline exhaust leakage detection device of hydrogen fuel cell vehicle
CN110513180B (en) Vehicle SCR system and backflow flow rate measuring module and method thereof
CN102297047B (en) Passage type EGR (Exhaust Gas Recirculation) system and method for dimethyl enther engine

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