Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/02—Circuit arrangements for generating control signals
  • F02D41/04—Introducing corrections for particular operating conditions
  • F02D41/047—Taking into account fuel evaporation or wall wetting
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/02—Circuit arrangements for generating control signals
  • F02D41/04—Introducing corrections for particular operating conditions
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01M—LUBRICATING OF MACHINES OR ENGINES IN GENERAL; LUBRICATING INTERNAL COMBUSTION ENGINES; CRANKCASE VENTILATING
  • F01M1/00—Pressure lubrication
  • F01M1/18—Indicating or safety devices
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01M—LUBRICATING OF MACHINES OR ENGINES IN GENERAL; LUBRICATING INTERNAL COMBUSTION ENGINES; CRANKCASE VENTILATING
  • F01M1/00—Pressure lubrication
  • F01M1/16—Controlling lubricant pressure or quantity
  • F01M2001/165—Controlling lubricant pressure or quantity according to fuel dilution in oil
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/30—Controlling fuel injection
  • F02D41/38—Controlling fuel injection of the high pressure type
  • F02D2041/389—Controlling fuel injection of the high pressure type for injecting directly into the cylinder
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D2250/00—Engine control related to specific problems or objectives
  • F02D2250/11—Oil dilution, i.e. prevention thereof or special controls according thereto
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/02—Circuit arrangements for generating control signals
  • F02D41/021—Introducing corrections for particular conditions exterior to the engine
  • F02D41/0235—Introducing corrections for particular conditions exterior to the engine in relation with the state of the exhaust gas treating apparatus
  • F02D41/027—Introducing corrections for particular conditions exterior to the engine in relation with the state of the exhaust gas treating apparatus to purge or regenerate the exhaust gas treating apparatus
  • F02D41/029—Introducing corrections for particular conditions exterior to the engine in relation with the state of the exhaust gas treating apparatus to purge or regenerate the exhaust gas treating apparatus the exhaust gas treating apparatus being a particulate filter
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/30—Controlling fuel injection
  • F02D41/38—Controlling fuel injection of the high pressure type
  • F02D41/40—Controlling fuel injection of the high pressure type with means for controlling injection timing or duration
  • F02D41/402—Multiple injections
  • F02D41/405—Multiple injections with post injections

Definitions

• the invention relates to a control method for the regeneration of a particulate filter fitted to a powertrain of a vehicle.
• the heterogeneity of the combustion processes in lean-mixture engines, in particular in diesel engines, has the effect of generating carbon particles, which cannot be burned efficiently in the engine. This results, for example, in the appearance, at the outlet of the exhaust line, of black smoke * This phenomenon is a source of pollution which we seek to reduce.
• the presence of a particulate filter in the exhaust line of the stroller makes it possible to considerably reduce the quantity of particles, dust and other soot, emitted into the atmosphere, and to comply with anti-pollution standards.
• Regeneration devices make it possible to periodically burn the particles trapped in the filter and to avoid clogging of the latter.
• the soot particles are essentially carbon elements, and their combustion consumes oxygen to form carbon dioxide. This is done by raising the temperature within the particulate filter to a temperature of the order of 550 to 650 ° C, temperature from which the carbon particles retained in the filter ignite spontaneously -
• the triggering of the regeneration of the filter is controlled by a computer which determines whether the regeneration should take place and, when it is in progress, whether it can continue.
• the computer receives information on the operation of the vehicle.
• This information includes, for example, the temperatures of the engine coolant, the ga ⁇ upstream and downstream of the particulate filter, the vehicle speed, the mass of soot accumulated in the particulate filter and the distance traveled since the last regeneration. .
• the computer checks conditions on this information and does not trigger regeneration unless all the conditions are satisfied. Regeneration is maintained, even if certain conditions are no longer satisfied for a period of time below a predetermined threshold, of the order of one to two minutes. If at least one condition is no longer satisfied for a duration greater than said threshold, then the regeneration process is interrupted.
• the engine operating conditions are changed to increase the temperature of the exhaust gases before they pass through the particulate filter.
• CQS modifications often relate to fuel injection, which can be delayed for at least one engine combustion chamber. In some cases also, a post-injection of fuel is carried out, during the final phase of the expansion time. This last injection brings no additional mechanical power to the engine, but increases the exhaust gas temperature. These modifications increase the fuel consumption and also the quantity of fuel which dissolves in the engine oil, passing through the space between the cylinder and the piston.
• the variation in the dilution rate is a function of the conditions of the injection of fuel into each of the combustion chambers.
• the inventor has in fact found that the most influential parameters on the dilution of the fuel in the oil were the conditions for fuel injection. By taking these conditions into account, we can best estimate the rate of dilution of fuel in engine oil.
• the variation in the dilution rate is a function of the following parameters; a number of phases of injection into the combustion chamber for a cycle; poiar each injection phase, the quantity of fuel injected and the position of a piston in the combustion chamber during the injection; and the fuel supply pressure. All injection phases are thus taken into account, as well as their individual parameters.
• the variation in the dilution rate is calculated on a delayed injection phase, the yield of which is degraded compared to a normal injection, and on a post-injection phase which does not participate in the supply of power to the engine.
• This type of operation is frequently used to control regeneration.
• the post-injection phase is well taken into account, unlike some evaluation methods based solely on the engine load, evaluated for example by an air flow or an air pressure at the intake.
• a coefficient for each injection phase comprising a multiplicative term equal to the product of the flow rate 'of fuel during said phase and the angular position of the crankshaft at the start of said injection phase and an end divider equal to the pressure fuel supply, the dilution change rate being a function of the sum of said coefficients over all injection phases.
• the coefficient for the delayed injection also includes a multiplier term equal to the rate of change equal to the rate of change in the amount of fuel injected between the delayed injection and the normal injection
• the coefficient for the post -injection further includes a multiplier term equal to the ratio of the amount of fuel injected from the post ⁇ injection and 1 delayed injection.
• the variation in the dilution rate is a continuous function, zero when the sum of said coefficients over all the injection phases is less than an influence threshold, and refines beyond said influence threshold. The inventor found, by comparison with series of measurements, that such a function validly represented the variation in the dilution rate.
• the invention also relates to a method for estimating a fuel dilution rate in the oil of a diesel engine during engine operation, the dilution rate being an integration over time of the variation in the dilution rate estimated as indicated above.
• the subject of the invention is also a method of controlling a motorization system comprising an engine, a particle filter receiving exhaust gases from the engine to retain particles of the exhaust gases, the method processing information and controlling the engine for obtaining the regeneration of the particulate filter when necessary, characterized in that the method establishes an estimate of the dilution rate of fuel in the oil by the preceding method of estimation of a dilution rate of fuel in the engine oil, the process allowing regeneration if the estimated dilution rate is below a predetermined dilution threshold.
• FIG. 2 is a timing diagram of different fuel injection modes
• Figure 3 is a flow diagram of the regeneration control of the particulate filter
• - Figure 4 is a graph showing the variation in dilution rate as a function of sum of coefficients.
• a motorization system implementing the method according to the invention and represented in FIG. 1, comprises a diesel type engine 1 supercharged by a turbocharger 2 and the exhaust gases of which are treated by a catalytic particle filter 3.
• the engine 1 is supplied with air by an air circuit comprising an air intake 11, a compressor 12 of the turbocharger 2, a discharge pipe 13 and an intake manifold 14 opening into combustion chambers of engine 1, a only chamber 15 being shown.
• the exhaust gases produced by combustion are evacuated from the chamber 15 by an exhaust pipe .16, pass through a turbine 17 of the turbocharger, then the catalytic particle filter 3.
• the exhaust gas recycling circuit includes a tapping 18 on the exhaust manifold, a selection valve 19 directing the exhaust gases towards the discharge line either via a cooler 20 or via a direct line 21.
• a computer 24 receives information on the operation of the motorization system and controls the engine 1. It determines in particular the conditions under which fuel is injected into the engine. Referring to FIG. 2, a diagram of the injection times is represented under three different conditions. The diagram has the angular position ⁇ of the crankshaft as the abscissa, the zero representing the position of the piston in top dead center (TDC) for the room of combustion considered.
• the injection is carried out in two stages, namely a pre-injection 51 followed by a main injection 52.
• the main injection 52 begins at a position ⁇ in of the crankshaft, generally before reaching top dead center.
• the injection is delayed, but always comprises a pre-injection 27, followed by a main injection 28.
• the main injection 28 begins at a position ⁇ ir of the crankshaft, generally after reaching the top dead center. If the temperature of the exhaust gases needs to be further raised, a post-injection 29 is carried out. Post-injection 29 begins at a position ip of the crankshaft.
• the computer 24 determines whether the regeneration should be controlled or not. For this, it establishes whether certain criteria are satisfied. When all the criteria are satisfied, a regeneration control signal is delivered. The computer maintains the regeneration control signal for a predetermined period after at least one criterion is no longer satisfied.
• the computer takes into account a criterion on the dilution rate Pdil of fuel in the engine oil.
• the dilution rate is estimated by the calculator, and if the estimate of the dilution rate Pdil is greater than a predetermined dilution threshold Sdil, the criterion is no longer met.
• Sdil a predetermined dilution threshold
• the estimation of the dilution rate is described below.
• the estimate of the dilution rate Dpii is initialized either at a zero value if the oil is new , or to a value previously estimated and stored.
• the test step 31 it is directed to a step 32 if no regeneration is in progress, or to a step 33 otherwise.
• a term dPdil is calculated by the opposite of the product of a fevap function of evaporation of the fuel contained in the oil and of a time step dt.
• the Févap function is calculated from a stored map, based on
• a term dPdil is calculated by the product of a variation in the dilution rate DQc and a time step dt.
• the variation in the rate of. DQc dilution is calculated using a compliant method
• the new dilution rate Pdil (n) is calculated by adding to the dilution rate at the time step 5 preceding Pdii (n-1) the term dPdil. This produces a digital integration of the variation in the DQc dilution rate.
• step 35 and 36 it is ensured that the dilution rate will not become negative. Then, in step 0 37, the dilution rate Pdil is compared to the predetermined dilution threshold Sdii: if it is higher, the criterion is not satisfied and regeneration is prohibited (step 38). Otherwise, regeneration is allowed (step 39).
• step 40 we wait for the time step dt to elapse before proceeding with a new calculation step, starting again at step 31 ”
• the variation in the dilution rate DQc is calculated according to the following formula: (DQc ⁇ O if Cir + Cîp ⁇ Sc t DQc ⁇ ax ⁇ Cir + C ⁇ -Sc) if Cir + C ⁇ ⁇ Sc
• Cir a coefficient of delayed injection
• Cip a coefficient of post-injection
• Se a predetermined influence threshold
• at a proportionality coefficient.
• the graph in Figure 3 represents this function with C ⁇ Cir + Cip,
• the delayed injection coefficient is defined by the following formula:
• Qir quantity of fuel injected during the delayed injection phase
• Pc common rail pressure supplying fuel to the injector.
• the post-injection coefficient is defined by the following formula:
• Cip ⁇ D, t ⁇ ⁇ lr Pc with Dip-ir ratio of the injection rate of post-injection to that of delayed injection
• Qip quantity of fuel injected during the post-injection phase
• ⁇ ip angular position of the crankshaft when post-in ection begins.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)
• Combined Controls Of Internal Combustion Engines (AREA)
• Networks Using Active Elements (AREA)
• Filtration Of Liquid (AREA)
• Processes For Solid Components From Exhaust (AREA)
• Electrical Discharge Machining, Electrochemical Machining, And Combined Machining (AREA)
• Perforating, Stamping-Out Or Severing By Means Other Than Cutting (AREA)
• Fuel-Injection Apparatus (AREA)

Priority Applications (3)

Applications Claiming Priority (2)

Publications (1)

Family

ID=34508367

Family Applications (1)

Country Status (7)

Families Citing this family (15)

Citations (5)

Family Cites Families (3)

• 2003
  • 2003-11-10 FR FR0313166A patent/FR2862087B1/fr not_active Expired - Fee Related
• 2004
  • 2004-10-29 DE DE602004019808T patent/DE602004019808D1/de active Active
  • 2004-10-29 JP JP2006538905A patent/JP4764826B2/ja not_active Expired - Fee Related
  • 2004-10-29 KR KR1020067009302A patent/KR20060117947A/ko active IP Right Grant
  • 2004-10-29 WO PCT/FR2004/050553 patent/WO2005047680A1/fr active Application Filing
  • 2004-10-29 EP EP04805796A patent/EP1694953B1/fr not_active Not-in-force
  • 2004-10-29 AT AT04805796T patent/ATE424504T1/de not_active IP Right Cessation

Patent Citations (5)

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events