WO2012081464A1 - ＮＯｘ浄化率低下原因診断装置 - Google Patents

ＮＯｘ浄化率低下原因診断装置 Download PDF

Info

Publication number
WO2012081464A1
WO2012081464A1 PCT/JP2011/078284 JP2011078284W WO2012081464A1 WO 2012081464 A1 WO2012081464 A1 WO 2012081464A1 JP 2011078284 W JP2011078284 W JP 2011078284W WO 2012081464 A1 WO2012081464 A1 WO 2012081464A1
Authority
WO
WIPO (PCT)
Prior art keywords
nox purification
failure
exhaust pipe
nox
cause
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.)
Ceased
Application number
PCT/JP2011/078284
Other languages
English (en)
French (fr)
Inventor
長岡　大治
輝男 中田
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.)
Isuzu Motors Ltd
Original Assignee
Isuzu Motors 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 Isuzu Motors Ltd filed Critical Isuzu Motors Ltd
Priority to EP11848567.1A priority Critical patent/EP2653684B1/en
Priority to US13/994,493 priority patent/US8973431B2/en
Priority to AU2011342305A priority patent/AU2011342305B2/en
Priority to CN201180059961.4A priority patent/CN103261609B/zh
Publication of WO2012081464A1 publication Critical patent/WO2012081464A1/ja
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/92—Chemical or biological purification of waste gases of engine exhaust gases
    • B01D53/94—Chemical or biological purification of waste gases of engine exhaust gases by catalytic processes
    • B01D53/9404—Removing only nitrogen compounds
    • B01D53/9409—Nitrogen oxides
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/92—Chemical or biological purification of waste gases of engine exhaust gases
    • B01D53/94—Chemical or biological purification of waste gases of engine exhaust gases by catalytic processes
    • B01D53/9459—Removing one or more of nitrogen oxides, carbon monoxide, or hydrocarbons by multiple successive catalytic functions; systems with more than one different function, e.g. zone coated catalysts
    • B01D53/9477—Removing one or more of nitrogen oxides, carbon monoxide, or hydrocarbons by multiple successive catalytic functions; systems with more than one different function, e.g. zone coated catalysts with catalysts positioned on separate bricks, e.g. exhaust systems
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/92—Chemical or biological purification of waste gases of engine exhaust gases
    • B01D53/94—Chemical or biological purification of waste gases of engine exhaust gases by catalytic processes
    • B01D53/9495—Controlling the catalytic process
    • 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
    • F01N13/00—Exhaust or silencing apparatus characterised by constructional features
    • F01N13/009—Exhaust or silencing apparatus characterised by constructional features having two or more separate purifying devices arranged in series
    • F01N13/0097—Exhaust or silencing apparatus characterised by constructional features having two or more separate purifying devices arranged in series the purifying devices are arranged in a single housing
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/02—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust
    • F01N3/021—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters
    • F01N3/033—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters in combination with other devices
    • F01N3/035—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for cooling, or for removing solid constituents of, exhaust by means of filters in combination with other devices with catalytic reactors
    • 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
    • F01N3/0807—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by using absorbents or adsorbents
    • F01N3/0814—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by using absorbents or adsorbents combined with catalytic converters, e.g. NOx absorption/storage reduction catalysts
    • 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
    • F01N3/0807—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by using absorbents or adsorbents
    • F01N3/0828—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by using absorbents or adsorbents characterised by the absorbed or adsorbed substances
    • F01N3/0842—Nitrogen oxides
    • 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
    • F01N3/105—General auxiliary catalysts, e.g. upstream or downstream of the main catalyst
    • F01N3/106—Auxiliary oxidation catalysts
    • 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
    • F01N2550/00—Monitoring or diagnosing the deterioration of exhaust systems
    • F01N2550/03—Monitoring or diagnosing the deterioration of exhaust systems of sorbing activity of adsorbents or absorbents
    • 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
    • F01N2610/03—Adding substances to exhaust gases the substance being hydrocarbons, e.g. engine fuel
    • 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
    • F01N2900/1631—Heat amount provided to exhaust apparatus
    • 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
    • F01N3/206—Adding periodically or continuously substances to exhaust gases for promoting purification, e.g. catalytic material in liquid form, NOx reducing agents
    • F01N3/2066—Selective catalytic reduction [SCR]
    • 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
    • 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
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/8158—With indicator, register, recorder, alarm or inspection means

Definitions

  • the present invention relates to a NOx purification rate lowering cause diagnosis device capable of performing self-diagnosis for specifying the cause of NOx purification rate lowering.
  • De-NOx nitrogen oxide reduction
  • HC-SCR hydrocarbon selective reduction catalyst device
  • LNT NOx occlusion device
  • NOx sensors are installed on the upstream and downstream sides of the NOx purification device, and the NOx purification rate is calculated from the ratio of the NOx concentrations detected by these NOx sensors. Can do.
  • the NOx purification rate may decrease even if these members break down.
  • the NOx purification rate also decreases due to failure of various members around the engine and failure of the reducing agent addition device (exhaust pipe fuel injection device). Therefore, even if the NOx purification rate decreases, it cannot be determined immediately that the NOx purification device is out of order. It is desirable to determine whether the cause of the decrease in the NOx purification rate is a failure of various members around the engine, a failure of the reducing agent addition device, or a failure of the NOx purification device.
  • an object of the present invention is to provide a NOx purification rate lowering cause diagnosis device capable of solving the above-described problems and performing a self-diagnosis that identifies the cause of the NOx purification rate lowering.
  • the present invention is a NOx purification rate reduction cause diagnosis device applied to an engine system having an exhaust pipe fuel injector, an oxidation catalyst device, and a NOx purification device, and when the NOx purification rate is reduced. If the error between the measured heat generation amount and the theoretical heat generation amount in the oxidation catalyst device during the exhaust pipe fuel injection is within a threshold when the exhaust pipe fuel injection is performed for diagnosis and the exhaust pipe fuel injection control unit for diagnosis, The cause of the decrease in the NOx purification rate is that the error between the NOx purification device failure identification unit that identifies a NOx purification device failure and the actual calorific value and the theoretical calorific value at the oxidation catalyst device when the exhaust pipe fuel injection is performed exceed a threshold value. In this case, the cause of the NOx purification rate reduction is provided with an oxidation catalyst device failure identification unit that identifies the oxidation catalyst device.
  • the present invention exhibits the following excellent effects.
  • FIG. 6 is a distribution diagram of heat generation along the exhaust pipe. It is a figure which shows the diagnostic matrix equivalent to the control procedure of FIG.
  • a NOx purification rate decrease cause diagnosis apparatus 1 includes a diagnostic exhaust pipe fuel injection control unit 2 that performs exhaust pipe fuel injection for diagnosis when the NOx purification rate decreases, and an exhaust gas If the error between the measured exhaust gas air-fuel ratio and the theoretical exhaust gas air-fuel ratio when the pipe fuel injection is not performed exceeds the threshold value, the cause of the NOx purification rate decrease is the engine-side failure specifying unit 3 that specifies the engine-side failure; If the error between the measured exhaust gas air-fuel ratio and the theoretical exhaust gas air-fuel ratio at the time of exhaust pipe fuel injection exceeds the threshold, the cause of the decrease in the NOx purification rate is determined as an exhaust pipe fuel injector failure.
  • the cause of the decrease in the NOx purification rate is identified as a NOx purification device failure.
  • the cause of the decrease in the NOx purification rate is the oxidation that identifies the oxidation catalyst device failure.
  • the specifying unit 6 and the combined fault specifying unit 7 are realized by software executed by an electronic control unit (Electronic Control Unit; hereinafter referred to as ECU). It is assumed that the ECU grasps all engine parameters (sensor detection values, calculation values, control values, etc.) necessary for controlling the engine system.
  • the engine system 201 to which the NOx purification rate reduction cause diagnosis device 1 of the present invention is applied includes an exhaust gas recirculation device (ExGRt Gas Recirculation; EGR) in the exhaust manifold 203 of the engine 202.
  • EGR exhaust gas recirculation
  • the EGR pipe 204 is connected, and the inlet of the exhaust turbine 206 of the turbocharger 205 is connected.
  • the downstream end of the EGR pipe 204 is connected to the intake manifold 207.
  • An exhaust pipe 208 is connected to the outlet of the exhaust turbine 206.
  • an exhaust pipe fuel injector 209 for injecting fuel into the exhaust pipe 208 in order from the upstream, an oxidation catalyst device (Diesel Oxidation Catalyst; hereinafter referred to as DOC) 210 for promoting the oxidation of the fuel and intermediate products, NOx purification device 211 such as HC-SCR, LNT, diesel particulate filter (DieselDPParticulate Filter; hereinafter referred to as DPF) 212 that collects particulate matter (Particulate Matter; PM) or catalyzed soot filter (Catalyzed Soot Filter) CSF) is installed.
  • Diesel Oxidation Catalyst Diesel Oxidation Catalyst
  • DPF diesel particulate filter
  • PM particulate Matter
  • Catalyzed Soot Filter catalyzed soot filter
  • the DOC 210, the NOx purification device 211, and the DPF 212 all use a catalyst.
  • the DOC 210, the NOx purification device 211, and the DPF 212 may be simply referred to as a catalyst.
  • the exhaust pipe fuel injector 209 is provided for injecting light oil as fuel into the exhaust pipe 208 when the particulate matter collected by the DPF 212 is removed by combustion (DPF regeneration, PM regeneration).
  • the injected fuel can be oxidized in the DOC 210, the NOx purifying device 211, the DPF 212, etc. by the intervention of the catalyst, and the exhaust gas temperature can be raised to the DPF regeneration temperature.
  • exhaust pipe fuel injection can be performed for the purpose of adding hydrocarbon as a reducing agent to HC-SCR and LNT. In the present invention, exhaust pipe fuel injection is performed for diagnosis of the cause of the NOx purification rate reduction.
  • the intake pipe 214 is connected to the air filter 213 that takes in air from the atmosphere, and the downstream end of the intake pipe 214 is connected to the inlet of the intake compressor 215 of the turbocharger 205.
  • a high-pressure side intake pipe 216 is connected to the outlet of the intake compressor 215, and a downstream end of the high-pressure side intake pipe 216 is connected to the intake manifold 207.
  • a first NOx sensor 221 that detects the engine outlet NOx concentration is installed upstream of the DOC 210 of the exhaust pipe 208, and a second NOx sensor 222 that detects the post-catalyst NOx concentration is installed downstream of the DPF 212.
  • An exhaust gas ⁇ sensor 223 that detects the air-fuel ratio of exhaust gas (actually measured exhaust gas air-fuel ratio) is installed downstream of the DPF 212.
  • the exhaust pipe 208 includes a first temperature sensor 224 that detects the temperature of the exhaust gas flowing into the DOC 210 upstream of the DOC 210 (DOC inlet temperature), a DOC outlet temperature (NOx purification device inlet temperature) between the DOC 210 and the NOx purification device 211.
  • the third temperature sensor 226 for detecting the NOx purification device outlet temperature (DPF inlet temperature) between the NOx purification device 211 and the DPF 212.
  • a four temperature sensor 227 is installed.
  • An air flow sensor (Mass Airflow ⁇ ⁇ ⁇ sensor; hereinafter referred to as MAF sensor) 228 for detecting the amount of intake air is installed in the intake pipe 214.
  • the first NOx sensor 221, the second NOx sensor 222, the exhaust gas ⁇ sensor 223, and the first to fourth temperature sensors 224 to 227 are separate from the self-diagnosis by the NOx purification rate decrease cause diagnosis device 1 of the present invention. It is assumed that each sensor is confirmed to be normal by the self-diagnosis of the sensor performed in the above.
  • the control procedure executed by the NOx purification rate decrease cause diagnosis device 1 is NOx purification rate decrease determination step S ⁇ b> 1 for determining whether or not the NOx purification rate is decreased, and whether or not the non-injection air-fuel ratio abnormality is determined.
  • Step S2 for identifying the cause of failure when exhaust pipe fuel injection is not performed ( ⁇ diagnosis A)
  • Step S3 for performing exhaust pipe fuel injection, and identifying the cause of failure when performing exhaust pipe fuel injection to determine whether the air-fuel ratio is abnormal when injection is present
  • the NOx purification rate lowering cause diagnosis apparatus 1 determines whether or not the NOx purification rate lowering occurs when a predetermined determination condition is satisfied in step S1 of the NOx purification rate lowering determination.
  • the determination conditions are that the exhaust gas temperature is stable and the vehicle travel is stable. If the vehicle travel is unstable, the engine state becomes a transitional state and the detection of the NOx concentration in the exhaust gas becomes unstable, so the determination of the NOx purification rate reduction is suspended.
  • the NOx purification rate is obtained from the post-catalyst NOx concentration and the pre-catalyst NOx concentration.
  • the engine outlet NOx concentration is used as the pre-catalyst NOx concentration
  • the detected value of the first NOx sensor 221 is the engine outlet.
  • NOx purification rate (1 ⁇ NOx concentration after catalyst / NOx concentration at engine outlet) ⁇ 100 (%) Is calculated by
  • the engine outlet NOx concentration may be estimated from a known theoretical formula or map using engine parameters without using the first NOx sensor 221.
  • the engine outlet NOx concentration and the post-catalyst NOx concentration are always detected at predetermined sampling intervals, and the NOx purification rate can be calculated in real time.
  • the NOx purification rate decrease cause diagnosis device 1 determines that the NOx purification rate has decreased when the state where the NOx purification rate has become equal to or lower than a preset threshold value continues for a predetermined time or more. By this determination, the NOx purification rate reduction cause diagnosis of the present invention is substantially started.
  • step S2 for specifying the cause of failure when the exhaust pipe fuel injection is not performed it is determined whether the air-fuel ratio is abnormal when there is no injection. That is, the engine-side failure specifying unit 3 calculates the theoretical exhaust gas air-fuel ratio at the installation position of the exhaust gas ⁇ sensor 223 by a known theoretical formula using the intake air amount and the fuel injection amount, and the exhaust gas ⁇ sensor 223 detects the theoretical exhaust gas air-fuel ratio. Compare with the measured exhaust gas air-fuel ratio. If the error between the actually measured exhaust gas air-fuel ratio and the theoretical exhaust gas air-fuel ratio exceeds a preset threshold value, it is abnormal. In this case, since the theoretical exhaust gas air-fuel ratio cannot be calculated correctly, the cause of the decrease in the NOx purification rate is specified as an engine-side failure.
  • the engine side failure means a failure of any of the members located upstream from the exhaust pipe 208.
  • the MAF sensor 228 fails, the intake air amount becomes inaccurate, so that the calculation of the theoretical exhaust gas air-fuel ratio becomes inaccurate.
  • the fuel injector in the engine 202 is clogged, an error in the fuel injection amount becomes large, and the calculation of the theoretical exhaust gas air-fuel ratio becomes inaccurate.
  • a diagnosis for further specifying the failure site may be performed.
  • known abnormality determination information for example, sensor output voltage abnormality relating to various members such as the EGR valve, the intake throttle, the turbocharger, and the MAF sensor 228 may be used.
  • step S2 If it is determined in step S2 that the error is equal to or less than the threshold value, it can be determined that the air-fuel ratio without injection is normal, and therefore there is no abnormality on the engine side, and the process proceeds to the next.
  • step S3 for exhaust pipe fuel injection the diagnostic exhaust pipe fuel injection control unit 2 performs exhaust pipe fuel injection.
  • Exhaust pipe fuel injection is performed with the same injection amount as during DPF regeneration.
  • the operator may be prompted to perform an operation during the control procedure, and the operator may perform the operation manually.
  • step S4 of specifying the cause of failure when performing exhaust pipe fuel injection it is determined whether or not the air-fuel ratio is abnormal with injection. That is, the exhaust pipe fuel injector failure identifying unit 4 uses the exhaust gas ⁇ sensor 223 according to a known theoretical formula using the exhaust gas weight exhausted from the engine 202 and the exhaust pipe fuel injection amount obtained from the intake air amount and the fuel injection amount. Is calculated and compared with the actually measured exhaust gas air-fuel ratio detected by the exhaust gas ⁇ sensor 223. If the error between the actually measured exhaust gas air-fuel ratio and the theoretical exhaust gas air-fuel ratio exceeds a preset threshold value, it is abnormal. In this case, since it has been confirmed that the theoretical exhaust gas air-fuel ratio can be calculated correctly, the cause of the decrease in the NOx purification rate is specified as an exhaust pipe fuel injector failure.
  • step S4 If it is determined in step S4 that the error is equal to or smaller than the threshold value, the air-fuel ratio with injection is normal, and therefore the exhaust pipe fuel injector 209 can be determined normal, and the process proceeds to the next.
  • step S5 of failure cause identification (catalyst temperature diagnosis) based on the catalyst heat generation pattern
  • the catalyst heat generation pattern is determined.
  • the catalyst heat generation pattern represents a distribution shape of heat generation based on actual measurement in a route passing through the DOC 210, the NOx purification device 211, and the DPF 212 along the exhaust pipe 208.
  • the temperature difference between the inlet and outlet of each catalyst is obtained based on the exhaust gas temperature at each catalyst inlet and outlet detected by the first to fourth temperature sensors 224 to 227, and from this temperature difference.
  • the integrated heat generation amount in each catalyst can be calculated. This is the measured calorific value.
  • the integrated heat generation amount that should be generated in each catalyst can be calculated by applying the exhaust pipe fuel injection amount, the heat generation coefficient of the fuel depending on each catalyst, the heat release amount, and the like to empirical formulas obtained in advance by experiments. This is the theoretical calorific value.
  • the actually measured calorific value and the theoretical calorific value are obtained as follows, for example.
  • the exhaust gas flow rate is calculated from each catalyst inlet temperature, intake air amount, and fuel injection amount during DPF regeneration.
  • the instantaneous catalyst heating value is calculated from the temperature difference between the inlet and outlet of the DOC 210, the exhaust gas flow rate, and the exhaust gas specific heat.
  • the integrated heat generation amount is calculated by integrating the catalyst heat generation amount.
  • Instantaneous catalyst heating value DOC inlet / outlet temperature difference ⁇ exhaust gas flow rate ⁇ exhaust gas specific heat, the instantaneous catalyst heating value is calculated.
  • the instantaneous theoretical calorific value is calculated from the lower calorific value (for example, 38.2 MJ / L) of the light oil as the fuel and the fuel consumption amount, and this is also integrated.
  • Instantaneous calorific value Lower heating value of diesel oil x Fuel consumption
  • the theoretical calorific value rises greatly in the vicinity of the inlet in the DOC 210 as shown by the broken line in the figure, and becomes constant thereafter.
  • the catalyst heat generation pattern # 1 indicated by the solid line almost coincides with the distribution based on the theoretical heat generation amount.
  • the catalyst heat generation pattern # 2 hardly rises in the DOC 210, rises greatly in the vicinity of the inlet in the NOx purification device 211, and becomes constant thereafter.
  • the catalyst heat generation pattern # 3 hardly rises in the DOC 210 or the NOx purification device 211, and rises greatly in the vicinity of the inlet of the DPF 212.
  • the measured heat generation amount and the theoretical heat generation amount in DOC 210 are in good agreement, and it can be determined that DOC 210 is functioning normally. Since the exhaust gas temperature has increased in the DOC 210, it cannot be determined from the catalyst heat generation pattern # 1 alone whether the NOx purification device 211 is functioning normally.
  • the actual heat generation amount and the theoretical heat generation amount are greatly different in the DOC 210, the actual heat generation amount is large in the NOx purification device 211, and the heat generation amount distribution after the NOx purification device 211 matches. ing. From this, it can be determined that the DOC 210 is abnormal. Further, it can be determined that the temperature raising function of the NOx purification device 211 is normal.
  • the measured heat generation amount and the theoretical heat generation amount are greatly different in the DOC 210 and the NOx purification device 211. Therefore, it can be determined that both the DOC 210 and the NOx purification device 211 are abnormal.
  • the failure site can be identified.
  • the error between the actual heat generation amount in the DOC 210 and the theoretical heat generation amount is within the threshold value. Can be determined to be normal. Since it has already been determined that there is no abnormality on the engine side and the exhaust pipe fuel injector 209 is also normal, only the NOx purification device 211 remains as a factor for reducing the NOx purification rate. Therefore, the NOx purification device failure identifying unit 5 identifies the cause of the decrease in the NOx purification rate as the NOx purification device failure.
  • the threshold value is set with the theoretical calorific value ⁇ 0.8 as a guide.
  • the catalyst heat generation pattern # 2 When the catalyst heat generation pattern # 2 is obtained, it is determined that the DOC 210 is abnormal. On the other hand, the error between the measured calorific value and the theoretical calorific value in the NOx purifying device 211 is within a threshold value (theoretical calorific value x 0.8 as a guideline), and although the temperature raising function of the NOx purifying device 211 is normal, the NOx purifying is performed. It cannot be uniquely determined that the cause of the rate decrease is an oxidation catalyst device failure. This is because, in the NOx purification device 211, the temperature raising function is normal, but the possibility that the NOx purification function is abnormal remains.
  • a threshold value theoretical calorific value x 0.8 as a guideline
  • the oxidation catalyst device failure identification unit 6 identifies the cause of the decrease in the NOx purification rate as an oxidation catalyst device failure.
  • the combined failure identification unit 7 identifies the cause of the decrease in the NOx purification rate as the oxidation catalyst device failure and the NOx purification device failure.
  • the diagnosis matrix of FIG. 5 can be defined equivalently to the control procedure of FIG. That is, as shown in FIG. 5, if the determination of ⁇ diagnosis A in step S2 is NG (abnormal), the cause of the decrease in the NOx purification rate is specified as an engine-side failure. If the determination of ⁇ diagnosis A in step S2 is OK (normal) and the determination of ⁇ diagnosis B in step S4 is NG, the cause of the decrease in the NOx purification rate is identified as an exhaust pipe fuel injector failure.
  • the catalyst temperature diagnosis in step S5 is not executed. However, if it is executed, for example, a catalyst heat generation pattern in which there is no temperature rise is obtained for all catalysts, and the determination in this case is NG.
  • both ⁇ diagnosis A and ⁇ diagnosis B are determined to be OK, it is as follows. If the determination of the catalyst temperature diagnosis is OK (the actual calorific value and the theoretical calorific value coincide, that is, the catalyst heat generation pattern # 1), it is specified that the NOx purification device has failed. If the determination of the catalyst temperature diagnosis is NG based on the catalyst heat generation pattern # 2, it is specified that the oxidation catalyst device has failed. If the determination of the catalyst temperature diagnosis is NG based on the catalyst heat generation pattern # 3, the oxidation catalyst device failure and the NOx purification device failure are identified.
  • exhaust pipe fuel injection is performed for diagnosis when the NOx purification rate is decreased, and the catalyst temperature diagnosis of the DOC 210 is performed.
  • a normal calorific value is obtained in the DOC 210, it can be identified as a NOx purification device failure, and if a normal calorific value is not obtained in the DOC 210, it can be identified as an oxidation catalyst device failure.
  • ⁇ diagnosis A and ⁇ diagnosis B are performed as in this embodiment, engine-side failures and exhaust pipe fuel injector failures can be specified, and the failure classification can be further subdivided.
  • the NOx purification rate lowering cause diagnosis apparatus 1 can be realized only by changing the software of the ECU without adding a new member to the engine system 201, so that the member cost does not increase.
  • the present invention is applied to the engine system 201 in which the exhaust pipe fuel injector 209, the DOC 210, the NOx purification device 211, and the DPF 212 are installed in order from the upstream side of the exhaust pipe 208, but there is no DOC 210.
  • the present invention can also be applied to an engine system in which the exhaust pipe fuel injector 209, the NOx purification device 211, and the DPF 212 are installed. Further, when the engine side failure, the exhaust pipe fuel injector failure, and the DPF failure are specified at the time of PM purification failure in the engine system in which the DOC 210 and the NOx purification device 211 are not provided and the exhaust pipe fuel injector 209 and the DPF 212 are installed.
  • the present invention can be applied.
  • the present invention can be applied to cause determination other than the urea water injector failure when the NOx purification rate is reduced.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Health & Medical Sciences (AREA)
  • Environmental & Geological Engineering (AREA)
  • Biomedical Technology (AREA)
  • Analytical Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Materials Engineering (AREA)
  • Toxicology (AREA)
  • Exhaust Gas After Treatment (AREA)
  • Exhaust Gas Treatment By Means Of Catalyst (AREA)

Abstract

　ＮＯｘ浄化率低下の原因を特定する自己診断が可能なＮＯｘ浄化率低下原因診断装置を提供する。　ＮＯｘ浄化率の低下時に診断用に排気管燃料噴射を実施させる診断用排気管燃料噴射制御部２と、排気管燃料噴射実施時に酸化触媒装置での実測発熱量と理論発熱量との誤差が閾値以内であれば、ＮＯｘ浄化率低下の原因はＮＯｘ浄化装置故障と特定するＮＯｘ浄化装置故障特定部５と、排気管燃料噴射実施時に酸化触媒装置での実測発熱量と理論発熱量との誤差が閾値を超えていれば、ＮＯｘ浄化率低下の原因は酸化触媒装置故障と特定する酸化触媒装置故障特定部６を備える。

Description

ＮＯｘ浄化率低下原因診断装置
　本発明は、ＮＯｘ浄化率低下の原因を特定する自己診断が可能なＮＯｘ浄化率低下原因診断装置に関する。
　エンジンの排気ガス流路に炭化水素選択還元触媒装置（Hydrocarbon Selective Catalytic Reduction；以下、ＨＣ－ＳＣＲという）、ＮＯｘ吸蔵器（Lean NOx Trap；以下、ＬＮＴ）等のＤｅ－ＮＯｘ（窒素酸化物低減）触媒付き後処理装置（以下、ＮＯｘ浄化装置という）を備える車両では、ＮＯｘ浄化装置の上下流にＮＯｘセンサを設置し、これらのＮＯｘセンサが検出するＮＯｘ濃度の比からＮＯｘ浄化率を算出することができる。
　このＮＯｘ浄化率の時間的変化を求め、ＮＯｘ浄化率が閾値を超えて低下したときＮＯｘ浄化装置が故障であるという自己診断（On-board Diagnostics；ＯＢＤ）ができるようになると好ましい。
特開２００８－７５６１０号公報 特開２０１０－１９６４９６号公報
　しかしながら、エンジンからＮＯｘ浄化装置の下流までには、排気ガス流路に沿って多様な部材が設置されており、これらの部材が故障した場合もＮＯｘ浄化率が低下することがある。例えば、エンジン周辺の諸部材の故障、還元剤添加装置（排気管燃料噴射装置）の故障によっても、ＮＯｘ浄化率が低下する。したがって、ＮＯｘ浄化率が低下しても直ちにＮＯｘ浄化装置が故障であるとは断定できない。ＮＯｘ浄化率低下の原因がエンジン周辺の諸部材の故障であるのか、還元剤添加装置の故障であるのか、ＮＯｘ浄化装置の故障であるのかを切り分けることが望まれる。
　そこで、本発明の目的は、上記課題を解決し、ＮＯｘ浄化率低下の原因を特定する自己診断が可能なＮＯｘ浄化率低下原因診断装置を提供することにある。
　上記目的を達成するために本発明は、排気管燃料噴射器と酸化触媒装置とＮＯｘ浄化装置とを有するエンジンシステムに適用されるＮＯｘ浄化率低下原因診断装置であって、ＮＯｘ浄化率の低下時に診断用に排気管燃料噴射を実施させる診断用排気管燃料噴射制御部と、前記排気管燃料噴射実施時に前記酸化触媒装置での実測発熱量と理論発熱量との誤差が閾値以内であれば、ＮＯｘ浄化率低下の原因はＮＯｘ浄化装置故障と特定するＮＯｘ浄化装置故障特定部と、前記排気管燃料噴射実施時に前記酸化触媒装置での実測発熱量と理論発熱量との誤差が閾値を超えていれば、ＮＯｘ浄化率低下の原因は酸化触媒装置と特定する酸化触媒装置故障特定部を備えたものである。
　本発明は次の如き優れた効果を発揮する。
　（１）ＮＯｘ浄化率低下の原因を特定する自己診断が可能となる。
本発明の一実施形態を示すＮＯｘ浄化率低下原因診断装置の構成図である。 図１のＮＯｘ浄化率低下原因診断装置が適用されるエンジンシステムの構成図である。 図１のＮＯｘ浄化率低下原因診断装置が実行する制御手順を示すフローチャートである。 排気管に沿った発熱の分布図である。 図３の制御手順と等価的な診断マトリクスを示す図である。
　以下、本発明の一実施形態を添付図面に基づいて詳述する。
　図１に示されるように、本発明に係るＮＯｘ浄化率低下原因診断装置１は、ＮＯｘ浄化率の低下時に診断用に排気管燃料噴射を実施させる診断用排気管燃料噴射制御部２と、排気管燃料噴射未実施時における実測排気ガス空燃比と理論排気ガス空燃比との誤差が閾値を超えていれば、ＮＯｘ浄化率低下の原因はエンジン側故障と特定するエンジン側故障特定部３と、排気管燃料噴射実施時における実測排気ガス空燃比と理論排気ガス空燃比との誤差が閾値を超えていれば、ＮＯｘ浄化率低下の原因は排気管燃料噴射器故障と特定する排気管燃料噴射器故障特定部４と、排気管燃料噴射実施時に酸化触媒装置での実測発熱量と理論発熱量との誤差が閾値以内であれば、ＮＯｘ浄化率低下の原因はＮＯｘ浄化装置故障と特定するＮＯｘ浄化装置故障特定部５と、排気管燃料噴射実施時に酸化触媒装置での実測発熱量と理論発熱量との誤差が閾値を超えていれば、ＮＯｘ浄化率低下の原因は酸化触媒装置故障と特定する酸化触媒装置故障特定部６と、排気管燃料噴射実施時に酸化触媒装置での実測発熱量と理論発熱量との誤差が閾値を超えており、かつ、ＮＯｘ浄化装置での実測発熱量と理論発熱量との誤差が閾値を超えていれば、酸化触媒装置故障及びＮＯｘ浄化装置故障と特定する複合故障特定部７とを備える。
　ＮＯｘ浄化率低下原因診断装置１を構成する診断用排気管燃料噴射制御部２、エンジン側故障特定部３、排気管燃料噴射器故障特定部４、ＮＯｘ浄化装置故障特定部５、酸化触媒装置故障特定部６、複合故障特定部７は、電子制御装置（Electronical Control Unit；以下、ＥＣＵという）が実行するソフトウェアで実現される。ＥＣＵは、エンジンシステムの制御に必要な全てのエンジンパラメータ（センサ検出値、演算値、制御値など）を把握しているものとする。
　図２に示されるように、本発明のＮＯｘ浄化率低下原因診断装置１が適用されるエンジンシステム２０１は、エンジン２０２の排気マニホールド２０３に、排気ガス再循環装置（Exhaust Gas Recirculation；ＥＧＲ）を構成するＥＧＲ管２０４が接続されると共に、ターボチャージャ２０５の排気タービン２０６の入口が接続される。ＥＧＲ管２０４の下流端は、吸気マニホールド２０７に接続される。排気タービン２０６の出口に排気管２０８が接続される。
　排気管２０８には上流から順に、排気管２０８内に燃料を噴射する排気管燃料噴射器２０９、燃料や中間生成物の酸化を促進する酸化触媒装置（Diesel Oxidation Catalyst；以下、ＤＯＣという）２１０、ＨＣ－ＳＣＲ、ＬＮＴなどのＮＯｘ浄化装置２１１、粒子状物質（Particulate Matter；ＰＭ）を捕集するディーゼルパティキュレートフィルタ（Diesel Particulate Filter；以下、ＤＰＦという）２１２又はキャタライズドスートフィルタ（Catalyzed Soot Filter；ＣＳＦ）が設置される。なお、ＤＯＣ２１０、ＮＯｘ浄化装置２１１、ＤＰＦ２１２は、いずれも触媒を使用するものであり、以下では、ＤＯＣ２１０、ＮＯｘ浄化装置２１１、ＤＰＦ２１２の意味で単に触媒と表記することがある。
　排気管燃料噴射器２０９は、ＤＰＦ２１２に捕集された粒子状物質を燃焼除去（ＤＰＦ再生、ＰＭ再生）するときに、排気管２０８内に燃料である軽油を噴射するために設けられる。噴射された燃料をＤＯＣ２１０、ＮＯｘ浄化装置２１１、ＤＰＦ２１２などにおいて触媒の介在により酸化させ、排気ガス温度をＤＰＦ再生温度まで上昇させることができる。また、ＨＣ－ＳＣＲ、ＬＮＴに対して還元剤としての炭化水素を添加する目的で排気管燃料噴射を行うことができる。本発明では、ＮＯｘ浄化率低下原因の診断用に排気管燃料噴射を実施することになる。
　大気からの空気が取り込まれるエアフィルタ２１３には吸気管２１４が接続され、吸気管２１４の下流端はターボチャージャ２０５の吸気コンプレッサ２１５の入口に接続される。吸気コンプレッサ２１５の出口には高圧側吸気管２１６が接続され、高圧側吸気管２１６の下流端は、吸気マニホールド２０７に接続される。
　排気管２０８のＤＯＣ２１０の上流には、エンジン出口ＮＯｘ濃度を検出する第一ＮＯｘセンサ２２１が設置され、ＤＰＦ２１２の下流には触媒後ＮＯｘ濃度を検出する第二ＮＯｘセンサ２２２が設置される。ＤＰＦ２１２の下流には排気ガスの空燃比（実測排気ガス空燃比）を検出する排気ガスλセンサ２２３が設置される。排気管２０８には、ＤＯＣ２１０の上流にＤＯＣ２１０に流れ込む排気ガスの温度（ＤＯＣ入口温度）を検出する第一温度センサ２２４、ＤＯＣ２１０とＮＯｘ浄化装置２１１との間にＤＯＣ出口温度（ＮＯｘ浄化装置入口温度）を検出する第二温度センサ２２５、ＮＯｘ浄化装置２１１とＤＰＦ２１２との間にＮＯｘ浄化装置出口温度（ＤＰＦ入口温度）を検出する第三温度センサ２２６、ＤＰＦ２１２の下流にＤＰＦ出口温度を検出する第四温度センサ２２７が設置される。吸気管２１４には、吸入空気量を検出する空気流量センサ（Mass Airflow sensor；以下、ＭＡＦセンサという）２２８が設置される。
　なお、第一ＮＯｘセンサ２２１、第二ＮＯｘセンサ２２２、排気ガスλセンサ２２３、第一～第四温度センサ２２４～２２７については、本発明のＮＯｘ浄化率低下原因診断装置１による自己診断とは別途に行われるセンサの自己診断により、各センサが正常であることが確認されているものとする。
　図３に示されるように、ＮＯｘ浄化率低下原因診断装置１が実行する制御手順は、ＮＯｘ浄化率低下かどうかを判定するＮＯｘ浄化率低下判定のステップＳ１、噴射無し時空燃比異常かどうかを判定する排気管燃料噴射未実施時の故障原因特定（λ診断Ａ）のステップＳ２、排気管燃料噴射実施のステップＳ３、噴射有り時空燃比異常かどうかを判定する排気管燃料噴射実施時の故障原因特定（λ診断Ｂ）のステップＳ４、触媒発熱パターンに基づく故障原因特定（触媒温度診断）のステップＳ５を有する。
　以下、各ステップにおける動作を詳しく説明する。
　ＮＯｘ浄化率低下原因診断装置１は、ＮＯｘ浄化率低下判定のステップＳ１にて、あらかじめ決められた判定条件が成立しているときに、ＮＯｘ浄化率低下かどうかを判定する。判定条件は、排気ガス温度が安定しており、かつ、車両走行が安定していることである。車両走行が不安定であると、エンジン状態が過渡的状態となって排気ガスのＮＯｘ濃度検出が不安定になってしまうので、ＮＯｘ浄化率低下の判定は保留する。
　ＮＯｘ浄化率は、触媒後ＮＯｘ濃度と触媒前ＮＯｘ濃度とから求められるが、本実施形態では、触媒前ＮＯｘ濃度としてエンジン出口ＮＯｘ濃度が用いられ、第一ＮＯｘセンサ２２１の検出値であるエンジン出口ＮＯｘ濃度と第二ＮＯｘセンサ２２２の検出値である触媒後ＮＯｘ濃度とから次式、
　　ＮＯｘ浄化率＝（１－触媒後ＮＯｘ濃度／エンジン出口ＮＯｘ濃度）
　　　　　　　　　　　　　　　　　　　　　　×１００　（％）
により演算される。エンジン出口ＮＯｘ濃度は、第一ＮＯｘセンサ２２１を使用せずに、エンジンパラメータを用いた公知の理論式あるいはマップから推定してもよい。
　エンジン出口ＮＯｘ濃度と触媒後ＮＯｘ濃度は、常時、所定のサンプリングインターバルで検出されており、リアルタイムにＮＯｘ浄化率を演算することができる。
　ＮＯｘ浄化率低下原因診断装置１は、ＮＯｘ浄化率があらかじめ設定した閾値以下になった状態があらかじめ設定した所定時間以上継続した場合、ＮＯｘ浄化率が低下したと判定する。この判定によって本発明のＮＯｘ浄化率低下原因診断が実質的に開始される。
　排気管燃料噴射未実施時の故障原因特定（λ診断Ａ）のステップＳ２にて、噴射無し時空燃比異常かどうかを判定する。すなわち、エンジン側故障特定部３は、吸入空気量と燃料噴射量とを用いる公知の理論式により排気ガスλセンサ２２３の設置位置における理論排気ガス空燃比を演算し、排気ガスλセンサ２２３が検出する実測排気ガス空燃比と比較する。実測排気ガス空燃比と理論排気ガス空燃比との誤差があらかじめ設定された閾値を超えていれば、異常である。この場合、理論排気ガス空燃比が正しく演算できていないので、ＮＯｘ浄化率低下の原因はエンジン側故障と特定する。
　エンジン側故障とは、排気管２０８よりも上流に位置する諸部材のいずれかの故障という意味である。例えば、ＭＡＦセンサ２２８が故障すると吸入空気量が不正確になるため、理論排気ガス空燃比の演算が不正確になることになる。あるいはエンジン２０２内の燃料噴射器に詰まりが発生すると、燃料噴射量の誤差が大きくなって、理論排気ガス空燃比の演算が不正確になることになる。このように、ＮＯｘ浄化率低下の原因がエンジン側故障と特定された場合には、故障部位をさらに特定する診断を行うとよい。これには、ＥＧＲ弁、吸気スロットル、ターボチャージャ、ＭＡＦセンサ２２８などの諸部材に関する公知の異常判定情報（例えば、センサ出力電圧異常）を援用するとよい。
　ステップＳ２の判定で誤差が閾値以下であれば、噴射無し時空燃比は正常、よってエンジン側には異常はないと判定できるから、次へ進む。
　排気管燃料噴射実施のステップＳ３にて、診断用排気管燃料噴射制御部２は、排気管燃料噴射を実施する。排気管燃料噴射は、ＤＰＦ再生時と同様の噴射量で行う。手動ＤＰＦ再生のための再生スイッチを装備した車両では、制御手順中にオペレータに操作を促し、オペレータが手動で実施するようにしてもよい。
　排気管燃料噴射実施時の故障原因特定（λ診断Ｂ）のステップＳ４にて、噴射有り時空燃比異常かどうかを判定する。すなわち、排気管燃料噴射器故障特定部４は、吸入空気量と燃料噴射量から求めたエンジン２０２が排出する排気ガス重量と排気管燃料噴射量とを用いる公知の理論式により排気ガスλセンサ２２３の設置位置における理論排気ガス空燃比を演算し、排気ガスλセンサ２２３が検出する実測排気ガス空燃比と比較する。実測排気ガス空燃比と理論排気ガス空燃比との誤差があらかじめ設定された閾値を超えていれば、異常である。この場合、理論排気ガス空燃比が正しく演算できることが確認されているので、ＮＯｘ浄化率低下の原因は排気管燃料噴射器故障と特定する。
　ステップＳ４の判定で誤差が閾値以下であれば、噴射有り時空燃比は正常、よって排気管燃料噴射器２０９は正常と判定できるから、次へ進む。
　触媒発熱パターンに基づく故障原因特定（触媒温度診断）のステップＳ５にて、触媒発熱パターンを判定する。触媒発熱パターンとは、排気管２０８に沿ってＤＯＣ２１０、ＮＯｘ浄化装置２１１、ＤＰＦ２１２を通る経路における実測に基づく発熱の分布形状を表すものである。
　図４に示されるように、第一～第四温度センサ２２４～２２７で検出される各触媒入口及び出口の排気ガス温度に基づいて触媒ごとの入口出口間の温度差を求め、この温度差から各触媒における積算発熱量を演算することができる。これを実測発熱量とする。一方、排気管燃料噴射量、各触媒に依存する燃料の発熱係数、放熱量などをあらかじめ実験により得た経験式に適用して各触媒において生ずるべき積算発熱量を演算することができる。これを理論発熱量とする。
　実測発熱量と理論発熱量は、例えば、次のように求められる。ＤＰＦ再生時に各触媒入口温度、吸入空気量、燃料噴射量から排気ガス流量を算出する。ＤＯＣ２１０の入口出口間の温度差、排気ガス流量、排気ガス比熱から瞬時の触媒発熱量を算出する。この触媒発熱量を積算して積算発熱量を算出する。具体的には、
　　瞬時の触媒発熱量＝ＤＯＣ出入口温度差×排気ガス流量×排気ガス比熱
により瞬時の触媒発熱量が演算される。一方、瞬時の理論発熱量は、燃料である軽油の低位発熱量（例えば、３８．２ＭＪ／Ｌ）と燃料消費量とから演算され、こちらも積算される。
　　瞬時の理論発熱量＝軽油の低位発熱量×燃料消費量
　理論発熱量は、図に破線で示されるように、ＤＯＣ２１０内の入口近傍で大きく立ち上がり、それ以降は一定となる。実線で示される触媒発熱パターン＃１は、理論発熱量に基づく分布とほぼ一致している。これに対し、触媒発熱パターン＃２は、ＤＯＣ２１０内ではほとんど立ち上がらず、ＮＯｘ浄化装置２１１内の入口近傍で大きく立ち上がり、それ以降は一定となる。触媒発熱パターン＃３は、ＤＯＣ２１０内でもＮＯｘ浄化装置２１１内でもほとんど立ち上がらず、ＤＰＦ２１２の入口近傍で大きく立ち上がる。
　触媒発熱パターン＃１を考察すると、ＤＯＣ２１０において実測発熱量と理論発熱量がよく一致しており、ＤＯＣ２１０は正常に機能していると判定できる。ＤＯＣ２１０において排気ガス温度が上昇しているため、ＮＯｘ浄化装置２１１が正常に機能しているかどうかは、この触媒発熱パターン＃１のみからは判定できない。
　触媒発熱パターン＃２を考察すると、ＤＯＣ２１０において実測発熱量と理論発熱量が大きく相違しており、かつ、ＮＯｘ浄化装置２１１では実測発熱量が大きく、ＮＯｘ浄化装置２１１以降の発熱量分布が一致している。これより、ＤＯＣ２１０に異常があると判定できる。また、ＮＯｘ浄化装置２１１の昇温機能は正常であると判定できる。
　触媒発熱パターン＃３を考察すると、ＤＯＣ２１０とＮＯｘ浄化装置２１１において実測発熱量と理論発熱量が大きく相違している。したがって、ＤＯＣ２１０とＮＯｘ浄化装置２１１は、共に異常があると判定できる。
　以上のような触媒発熱パターンによる考察と、ＮＯｘ浄化率低下が判定されているという事象とを組み合わせることで、故障部位が特定できる。
　第一～第四温度センサ２２４～２２７で検出される排気ガス温度から触媒発熱パターン＃１が得られた場合、ＤＯＣ２１０での実測発熱量と理論発熱量との誤差が閾値以内となるので、ＤＯＣ２１０は正常と判定できる。既に、エンジン側に異常がなく、排気管燃料噴射器２０９も正常であることが判定されているので、ＮＯｘ浄化率を低下させる要因としてはＮＯｘ浄化装置２１１しか残っていない。よって、ＮＯｘ浄化装置故障特定部５は、ＮＯｘ浄化率低下の原因はＮＯｘ浄化装置故障と特定する。閾値は、例えば、理論発熱量×０．８を目安に設定する。
　触媒発熱パターン＃２が得られた場合、ＤＯＣ２１０に異常があることは確定する。一方、ＮＯｘ浄化装置２１１での実測発熱量と理論発熱量との誤差が閾値（理論発熱量×０．８を目安）以内となり、ＮＯｘ浄化装置２１１の昇温機能は正常であるものの、ＮＯｘ浄化率低下の原因が酸化触媒装置故障であるとは一意的に断定できない。なぜならば、ＮＯｘ浄化装置２１１において、昇温機能は正常であるが、ＮＯｘ浄化の機能が異常である可能性が残る。しかし、発明者らの知見によれば、触媒の昇温機能異常とＮＯｘ浄化機能異常は同時に発生するので、酸化触媒装置故障の可能性が高い。よって、酸化触媒装置故障特定部６は、ＮＯｘ浄化率低下の原因は酸化触媒装置故障と特定する。
　触媒発熱パターン＃３が得られた場合、ＤＯＣ２１０とＮＯｘ浄化装置２１１に異常があることが確定する。よって、複合故障特定部７は、ＮＯｘ浄化率低下の原因は酸化触媒装置故障及びＮＯｘ浄化装置故障と特定する。
　図３の制御手順と等価的に図５の診断マトリクスを定義することができる。すなわち、図５に示されるように、ステップＳ２のλ診断Ａの判定がＮＧ（異常）であるならば、ＮＯｘ浄化率低下の原因はエンジン側故障と特定される。ステップＳ２のλ診断Ａの判定がＯＫ（正常）であってステップＳ４のλ診断Ｂの判定がＮＧであるならば、ＮＯｘ浄化率低下の原因は排気管燃料噴射器故障と特定される。ここで、図３の手順ではステップＳ５の触媒温度診断は実行されないが、仮に実行すれば、例えば、全ての触媒で昇温がない触媒発熱パターンが得られ、この場合の判定はＮＧとなる。
　λ診断Ａ、λ診断Ｂの判定が共にＯＫである場合は、次のようになる。触媒温度診断の判定がＯＫ（実測発熱量と理論発熱量が一致、つまり触媒発熱パターン＃１）であるならば、ＮＯｘ浄化装置故障と特定される。触媒温度診断の判定が触媒発熱パターン＃２によってＮＧであるならば、酸化触媒装置故障と特定される。触媒温度診断の判定が触媒発熱パターン＃３によってＮＧであるならば、酸化触媒装置故障及びＮＯｘ浄化装置故障と特定される。
　以上説明したように、本発明に係るＮＯｘ浄化率低下原因診断装置１によれば、ＮＯｘ浄化率の低下時に診断用に排気管燃料噴射を実施させ、ＤＯＣ２１０の触媒温度診断を行うようにした。これにより、ＤＯＣ２１０で正常な発熱量が得られていればＮＯｘ浄化装置故障と特定でき、ＤＯＣ２１０で正常な発熱量が得られていなければ酸化触媒装置故障と特定できる。
　さらに、本実施形態のように、λ診断Ａ及びλ診断Ｂを行うようにすると、エンジン側故障、排気管燃料噴射器故障が特定でき、故障の切り分けがいっそう細分化できる。
　本発明に係るＮＯｘ浄化率低下原因診断装置１は、エンジンシステム２０１に新規な部材を追加することなく、ＥＣＵのソフトウェアを変更するのみで実現できるので、部材コストが上昇することがない。
　本実施形態では、排気管２０８の上流から順に、排気管燃料噴射器２０９、ＤＯＣ２１０、ＮＯｘ浄化装置２１１、ＤＰＦ２１２が設置されたエンジンシステム２０１に本発明を適用するものとしたが、ＤＯＣ２１０がなく、排気管燃料噴射器２０９、ＮＯｘ浄化装置２１１、ＤＰＦ２１２が設置されたエンジンシステムにも本発明は適用できる。さらに、ＤＯＣ２１０、ＮＯｘ浄化装置２１１がなく、排気管燃料噴射器２０９、ＤＰＦ２１２が設置されたエンジンシステムにおけるＰＭ浄化の不具合時にエンジン側故障、排気管燃料噴射器故障、ＤＰＦ故障を特定する場合にも本発明が応用できる。また、ＮＯｘ浄化に尿素ＳＣＲを用いるエンジンシステムに対しては、ＮＯｘ浄化率低下時に尿素水噴射器故障以外の原因特定に本発明を応用することができる。
　１　ＮＯｘ浄化率低下原因診断装置
　２　診断用排気管燃料噴射制御部
　３　エンジン側故障特定部
　４　排気管燃料噴射器故障特定部
　５　ＮＯｘ浄化装置故障特定部
　６　酸化触媒装置故障特定部
　７　複合故障特定部

Claims (2)

  1. 　排気管燃料噴射器と酸化触媒装置とＮＯｘ浄化装置とを有するエンジンシステムに適用されるＮＯｘ浄化率低下原因診断装置であって、
    　ＮＯｘ浄化率の低下時に診断用に排気管燃料噴射を実施させる診断用排気管燃料噴射制御部と、
    　前記排気管燃料噴射実施時に前記酸化触媒装置での実測発熱量と理論発熱量との誤差が閾値以内であれば、ＮＯｘ浄化率低下の原因はＮＯｘ浄化装置故障と特定するＮＯｘ浄化装置故障特定部と、
    　前記排気管燃料噴射実施時に前記酸化触媒装置での実測発熱量と理論発熱量との誤差が閾値を超えていれば、ＮＯｘ浄化率低下の原因は酸化触媒装置と特定する酸化触媒装置故障特定部とを備えたことを特徴とするＮＯｘ浄化率低下原因診断装置。
  2. 　排気管燃料噴射実施時に前記酸化触媒装置での実測発熱量と理論発熱量との誤差が閾値を超えており、かつ、前記ＮＯｘ浄化装置での実測発熱量と理論発熱量との誤差が閾値を超えていれば、酸化触媒装置故障及びＮＯｘ浄化装置故障と特定する複合故障特定部をさらに備えた
    　請求項１記載のＮＯｘ浄化率低下原因診断装置。
PCT/JP2011/078284 2010-12-16 2011-12-07 ＮＯｘ浄化率低下原因診断装置 Ceased WO2012081464A1 (ja)

Priority Applications (4)

Application Number Priority Date Filing Date Title
EP11848567.1A EP2653684B1 (en) 2010-12-16 2011-12-07 DEVICE FOR DIAGNOSING CAUSES OF DECREASES IN NOx CONVERSION EFFICIENCY
US13/994,493 US8973431B2 (en) 2010-12-16 2011-12-07 Apparatus for diagnosing causes of NOx conversion efficiency degradation
AU2011342305A AU2011342305B2 (en) 2010-12-16 2011-12-07 Device for diagnosing causes of decreases in NOx conversion efficiency
CN201180059961.4A CN103261609B (zh) 2010-12-16 2011-12-07 NOx净化率降低原因诊断装置

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2010-280889 2010-12-16
JP2010280889A JP5760423B2 (ja) 2010-12-16 2010-12-16 ＮＯｘ浄化率低下原因診断装置

Publications (1)

Publication Number Publication Date
WO2012081464A1 true WO2012081464A1 (ja) 2012-06-21

Family

ID=46244571

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2011/078284 Ceased WO2012081464A1 (ja) 2010-12-16 2011-12-07 ＮＯｘ浄化率低下原因診断装置

Country Status (6)

Country Link
US (1) US8973431B2 (ja)
EP (1) EP2653684B1 (ja)
JP (1) JP5760423B2 (ja)
CN (1) CN103261609B (ja)
AU (1) AU2011342305B2 (ja)
WO (1) WO2012081464A1 (ja)

Families Citing this family (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101158816B1 (ko) * 2009-08-21 2012-06-26 기아자동차주식회사 디젤 차량의 배기 장치
JP5360307B2 (ja) * 2010-11-02 2013-12-04 トヨタ自動車株式会社 内燃機関の制御装置
EP2682576A4 (en) * 2011-03-03 2015-04-08 Toyota Motor Co Ltd SYSTEM FOR DETERMINING CATALYST WEAR
AT512760B1 (de) * 2012-03-21 2014-05-15 Avl List Gmbh Verfahren zum Betreiben einer Brennkraftmaschine
US9084966B2 (en) * 2012-11-29 2015-07-21 GM Global Technology Operations LLC Diesel oxidation catalyst aging level determination using NOX sensor NO2 interference
US9708960B2 (en) * 2013-05-08 2017-07-18 Cummins Ip, Inc. Exhaust aftertreatment system diagnostic and conditioning
JP6169427B2 (ja) * 2013-07-10 2017-07-26 日野自動車株式会社 アフターターボキャタリストの異常検知方法
US9068495B2 (en) * 2013-09-12 2015-06-30 GM Global Technology Operations LLC Oxidation catalyst/hydrocarbon injector testing system
US9752488B2 (en) * 2015-10-27 2017-09-05 Cummins, Inc. Systems and methods of an on-board NOx monitor reset test
US10208696B2 (en) * 2016-10-21 2019-02-19 GM Global Technology Operations LLC Multivariable engine torque and emission closed-loop control for internal combustion engine
DE102017124757A1 (de) * 2017-10-23 2017-12-28 FEV Europe GmbH Abgasbehandlungssystem für ein kraftfahrzeug
DE112017008280T5 (de) * 2017-12-18 2020-09-10 Cummins Emission Solutions Inc. Dezidierte Wärmeverwaltung für ein SCR-System
CN108930578B (zh) * 2018-06-27 2020-09-29 潍柴动力股份有限公司 Doc中毒的检测和保护方法
JP7310720B2 (ja) * 2020-05-29 2023-07-19 いすゞ自動車株式会社 触媒状態検知装置
CN112557040B (zh) * 2020-11-16 2022-03-15 东风汽车集团有限公司 发动机瞬态soot排放量预估方法
DE102021200701A1 (de) * 2021-01-27 2022-07-28 Robert Bosch Gesellschaft mit beschränkter Haftung Verfahren und Vorrichtung zur Diagnose eines Katalysators mit einem elektrischen Heizer
GB2619856B (en) * 2021-03-26 2025-03-26 Cummins Power Generation Inc Dual leg aftertreatment system
CN114991921B (zh) * 2022-05-25 2024-01-09 深圳市众卡汽车零部件有限公司 一种scr效率低故障原因排查方法
US11815044B1 (en) 2022-06-09 2023-11-14 Cummins Inc. Systems and methods for selective catalytic reduction (SCR) multipoint diagnosis
KR20260048751A (ko) * 2024-10-04 2026-04-13 현대자동차주식회사 오토 인코더를 이용한 배출 가스의 증가 원인 진단 장치, 방법 및 차량

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005201143A (ja) * 2004-01-15 2005-07-28 Honda Motor Co Ltd 排気浄化装置の劣化判定装置
JP2005351153A (ja) * 2004-06-10 2005-12-22 Toyota Motor Corp 触媒劣化判定装置
JP2006291742A (ja) * 2005-04-06 2006-10-26 Toyota Motor Corp 内燃機関の触媒劣化検出装置
JP2008075610A (ja) 2006-09-23 2008-04-03 Hino Motors Ltd 排気処理装置
JP2009085079A (ja) * 2007-09-28 2009-04-23 Toyota Motor Corp 内燃機関の触媒劣化検出装置
JP2010196496A (ja) 2009-02-23 2010-09-09 Toyota Motor Corp 排気浄化装置

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10237382A1 (de) * 2002-08-12 2004-03-04 Volkswagen Ag Verfahren zum Betrieb eines magerlauffähigen Verbrennungsmotors mit einem Abgasreinigungssystem
US6925796B2 (en) * 2003-11-19 2005-08-09 Ford Global Technologies, Llc Diagnosis of a urea SCR catalytic system
US20070044456A1 (en) * 2005-09-01 2007-03-01 Devesh Upadhyay Exhaust gas aftertreatment systems
US7418816B2 (en) * 2005-09-01 2008-09-02 Ford Global Technologies, Llc Exhaust gas aftertreatment systems
US8245567B2 (en) * 2008-08-19 2012-08-21 GM Global Technology Operations LLC On board diagnostic monitor of NOx conversion efficiency for aftertreatment device
US8201444B2 (en) * 2008-08-19 2012-06-19 GM Global Technology Operations LLC Aftertreatment device NOx conversion efficiency diagnostics using on board adaptive diagnostic algorithm
JP5170689B2 (ja) * 2009-01-14 2013-03-27 トヨタ自動車株式会社 内燃機関の排気浄化装置
US8539757B2 (en) * 2009-01-16 2013-09-24 Toyota Jidosha Kabushiki Kaisha Exhaust purification apparatus for internal combustion engine
US8091416B2 (en) * 2009-01-16 2012-01-10 GM Global Technology Operations LLC Robust design of diagnostic enabling conditions for SCR NOx conversion efficiency monitor
US8726723B2 (en) * 2010-02-23 2014-05-20 Cummins Emission Solutions Detection of aftertreatment catalyst degradation

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005201143A (ja) * 2004-01-15 2005-07-28 Honda Motor Co Ltd 排気浄化装置の劣化判定装置
JP2005351153A (ja) * 2004-06-10 2005-12-22 Toyota Motor Corp 触媒劣化判定装置
JP2006291742A (ja) * 2005-04-06 2006-10-26 Toyota Motor Corp 内燃機関の触媒劣化検出装置
JP2008075610A (ja) 2006-09-23 2008-04-03 Hino Motors Ltd 排気処理装置
JP2009085079A (ja) * 2007-09-28 2009-04-23 Toyota Motor Corp 内燃機関の触媒劣化検出装置
JP2010196496A (ja) 2009-02-23 2010-09-09 Toyota Motor Corp 排気浄化装置

Also Published As

Publication number Publication date
US8973431B2 (en) 2015-03-10
JP5760423B2 (ja) 2015-08-12
EP2653684A4 (en) 2016-11-09
CN103261609A (zh) 2013-08-21
AU2011342305A1 (en) 2013-07-18
US20130306171A1 (en) 2013-11-21
AU2011342305B2 (en) 2016-02-25
EP2653684B1 (en) 2018-05-30
CN103261609B (zh) 2015-04-29
JP2012127302A (ja) 2012-07-05
EP2653684A1 (en) 2013-10-23

Similar Documents

Publication Publication Date Title
JP5760423B2 (ja) ＮＯｘ浄化率低下原因診断装置
JP5720230B2 (ja) パティキュレートフィルタシステム
CN105888797B (zh) 用于监测颗粒过滤器的方法
JP6325532B2 (ja) 異常に頻度が高いディーゼルパティキュレートフィルタ再生を検出する方法、エンジン、排気後処理システム、警告システム及び方法
JP5993293B2 (ja) 異常診断装置
US9074507B2 (en) Event-based deviation integration temperature control loop diagnostic system
US20120023911A1 (en) Detection of exhaust particulate filter substrate failure
US20150240695A1 (en) Detecting over-temperature in exhaust system
US20140144220A1 (en) Diagnostic operation strategy for diesel oxidation catalyst aging level determination using nox sensor no2 interference
CN101379284A (zh) 废气净化系统的控制方法及废气净化系统
CN102037230A (zh) NOx传感器的异常诊断装置及异常诊断方法
CN101278110A (zh) 用于排气后处理系统的诊断方法
JP2012036860A (ja) 触媒劣化診断装置
KR20150024384A (ko) 배기 후 처리 시스템의 구성요소 모니터링 방법, 배기 처리 시스템 및 배기 처리 시스템 컨트롤러
US20130025262A1 (en) Exhaust purification apparatus for engine
JP2010523891A (ja) 内燃機関の排気管の触媒コンバータの作動状態を制御する方法及び装置
KR20190134944A (ko) 배기 정화 시스템 및 이의 제어방법
JP2019116876A (ja) センサ診断システム
JP5831162B2 (ja) ＮＯｘセンサの異常診断方法、ＮＯｘセンサの異常診断システム、及び内燃機関
WO2013073450A1 (ja) ＮＯｘセンサの異常診断方法、ＮＯｘセンサの異常診断システム、及び内燃機関
JP6958130B2 (ja) 内燃機関の診断装置
JP2021173218A (ja) 触媒劣化度推定装置
JP2016188626A (ja) ドージングバルブの交換時期診断方法
JP5874342B2 (ja) ＮＯｘセンサの異常診断方法、ＮＯｘセンサの異常診断システム、及び内燃機関のＮＯｘ排出濃度推定方法
JP2022018447A (ja) 温度センサの診断装置

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 11848567

Country of ref document: EP

Kind code of ref document: A1

WWE Wipo information: entry into national phase

Ref document number: 13994493

Country of ref document: US

NENP Non-entry into the national phase

Ref country code: DE

WWE Wipo information: entry into national phase

Ref document number: 2011848567

Country of ref document: EP

ENP Entry into the national phase

Ref document number: 2011342305

Country of ref document: AU

Date of ref document: 20111207

Kind code of ref document: A