Patent classifications
F01N3/32
Method to Control an Exhaust Gas After-Treatment System for an Exhaust Gas System of an Internal Combustion Engine
A method is disclosed to control an exhaust gas after-treatment system with at least one catalytic converter arranged along an exhaust duct and a burner, which is suited to introduce exhaust gases into the exhaust duct, wherein inside the burner there is defined a combustion chamber, which receives fresh air through an air feeding circuit and fuel from an injector; the method comprises housing a temperature and pressure sensor interposed between a pumping device and the burner or leaving the burner; acquiring the pressure signal generated by the combustion inside the combustion chamber and detected by said temperature and pressure sensor; and controlling the combustion inside the combustion chamber as a function of said pressure signal.
Method to Control an Exhaust Gas After-Treatment System for an Exhaust Gas System of an Internal Combustion Engine
A method is disclosed to control an exhaust gas after-treatment system with at least one catalytic converter arranged along an exhaust duct and a burner, which is suited to introduce exhaust gases into the exhaust duct, wherein inside the burner there is defined a combustion chamber, which receives fresh air through an air feeding circuit and fuel from an injector; the method comprises housing a temperature and pressure sensor interposed between a pumping device and the burner or leaving the burner; acquiring the pressure signal generated by the combustion inside the combustion chamber and detected by said temperature and pressure sensor; and controlling the combustion inside the combustion chamber as a function of said pressure signal.
System for thermal management of engine exhaust
Methods and systems are provided for maintaining a temperature of exhaust gases of an engine within a temperature range at which catalytic conversion is most efficient. In one example, a method for controlling a temperature of exhaust gases entering a Selective Catalytic Reduction (SCR) system for an engine comprises delivering pressurized air into the exhaust gases upstream of the SCR system, the pressurized air cooled by an air cooler; and adjusting a degree of pressurization by adjusting operation of a turbocharger pressurizing the pressurized air. In one embodiment, the air cooler may be a charge air cooler of a primary turbocharger of the engine, which may flow pressurized air both to the engine and to the SCR system. In other embodiments, the air may be pressurized by an air pump or a secondary dilution turbocharger, and cooled by a secondary charge air cooler.
Method to Control a Burner for an Exhaust System of an Internal Combustion Engine
A method to control an internal combustion engine having an exhaust duct and an exhaust gas after-treatment system comprising at least one catalytic converter arranged along the exhaust duct; an oxygen sensor housed along the exhaust duct and arranged upstream of said at least one catalytic converter; and a burner suited to introduce the exhaust gases into the exhaust duct upstream of the oxygen sensor the method provides the steps of calculating the thermal power required to reach the nominal operating temperature of said at least one catalytic converter obtained with an objective value of the air/fuel ratio value; and determining both the objective fuel flow rate and the objective air flow rate to be fed to the burner to obtain the thermal power required to reach the nominal operating temperature of said at least one catalytic converter.
Method to Control a Burner for an Exhaust System of an Internal Combustion Engine
A method to control an internal combustion engine provided with an exhaust system for the exhaust gases of a vehicle having an exhaust duct and an exhaust gas after-treatment system comprising at least one catalytic converter arranged along the exhaust duct; a burner suited to introduce the exhaust gases into the exhaust duct to speed up the heating of said at least one catalytic converter, wherein a combustion chamber is defined inside the burner which receives fuel from an injector, designed to inject the fuel inside the combustion chamber and the fresh air by means of an air feeding circuit provided with a pumping device that feeds the air, a shut-off valve arranged upstream of the burner and a mass air flow sensor interposed between the pumping device and the shut-off valve; the method provides the following steps: calculating the thermal power required to reach the nominal operating temperature of said at least one catalytic converter; determining the objective air flow rate to be fed to the burner to obtain said thermal power required to reach the nominal operating temperature of said at least one catalytic converter; determining the nominal number of revolutions with which to operate the pumping device by means of a map depending on the objective air flow rate, on the ambient pressure, on the ambient temperature and on the pressure of the air entering the burner; determining a closed-loop contribution of the number of revolutions with which to operate the pumping device by means of a PID controller which tries to zero a difference between the objective air flow rate and the air flow rate detected by the mass air flow sensor; determining a further contribution of the number of revolutions with which to operate the pumping device depending on the integral action of the PID controller under stationary conditions; and determining the actual number of revolutions with which to operate the pumping device by the sum of the nominal number of revolutions, the closed-loop contribution of the number of revolutions with which to operate the pumping device and the further contribution of the number of revolutions with which to operate the pumping device.
Method to Control a Burner for an Exhaust System of an Internal Combustion Engine
A method to control an internal combustion engine provided with an exhaust system for the exhaust gases of a vehicle having an exhaust duct and an exhaust gas after-treatment system comprising at least one catalytic converter arranged along the exhaust duct; a burner suited to introduce the exhaust gases into the exhaust duct to speed up the heating of said at least one catalytic converter, wherein a combustion chamber is defined inside the burner which receives fuel from an injector, designed to inject the fuel inside the combustion chamber and the fresh air by means of an air feeding circuit provided with a pumping device that feeds the air, a shut-off valve arranged upstream of the burner and a mass air flow sensor interposed between the pumping device and the shut-off valve; the method provides the following steps: calculating the thermal power required to reach the nominal operating temperature of said at least one catalytic converter; determining the objective air flow rate to be fed to the burner to obtain said thermal power required to reach the nominal operating temperature of said at least one catalytic converter; determining the nominal number of revolutions with which to operate the pumping device by means of a map depending on the objective air flow rate, on the ambient pressure, on the ambient temperature and on the pressure of the air entering the burner; determining a closed-loop contribution of the number of revolutions with which to operate the pumping device by means of a PID controller which tries to zero a difference between the objective air flow rate and the air flow rate detected by the mass air flow sensor; determining a further contribution of the number of revolutions with which to operate the pumping device depending on the integral action of the PID controller under stationary conditions; and determining the actual number of revolutions with which to operate the pumping device by the sum of the nominal number of revolutions, the closed-loop contribution of the number of revolutions with which to operate the pumping device and the further contribution of the number of revolutions with which to operate the pumping device.
Method To Control A Burner For An Exhaust System Of An Internal Combustion Engine
A method to control an internal combustion engine having an exhaust duct and an exhaust gas after-treatment system comprising at least one catalytic converter arranged along the exhaust duct; an oxygen sensor housed along the exhaust duct and arranged upstream of said at least one catalytic converter; and a burner suited to introduce the exhaust gases into the exhaust duct upstream of the oxygen sensor the method provides the steps of identifying the operation phases in which the internal combustion engine is turned off and the burner is turned on so that the oxygen sensor is exclusively hit by the exhaust gases produced by the burner; acquiring the signal generated by the oxygen sensor; and using the signal generated by the oxygen sensor to determine the objective fuel flow rate and the objective air flow rate to be fed to the burner.
Method To Control A Burner For An Exhaust System Of An Internal Combustion Engine
A method to control an internal combustion engine having an exhaust duct and an exhaust gas after-treatment system comprising at least one catalytic converter arranged along the exhaust duct; an oxygen sensor housed along the exhaust duct and arranged upstream of said at least one catalytic converter; and a burner suited to introduce the exhaust gases into the exhaust duct upstream of the oxygen sensor the method provides the steps of identifying the operation phases in which the internal combustion engine is turned off and the burner is turned on so that the oxygen sensor is exclusively hit by the exhaust gases produced by the burner; acquiring the signal generated by the oxygen sensor; and using the signal generated by the oxygen sensor to determine the objective fuel flow rate and the objective air flow rate to be fed to the burner.
Multi-Tier Exhaust Burner Control For SCR Catalyst Pre-Heating
An exhaust control system for a vehicle includes a temperature sensor positioned downstream of an exhaust burner and upstream of an SCR catalyst in an exhaust system. The temperature sensor is configured to generate a measurement signal indicative a temperature of exhaust flowing through the exhaust system at an outlet of a DPF positioned downstream of the exhaust burner. An exhaust control module is configured to turn the exhaust burner on to heat the exhaust, monitor the temperature of the exhaust based on the measurement signal, subsequent to turning the exhaust burner on, turn the exhaust burner off based on an upper threshold temperature of the exhaust, and, subsequent to turning the exhaust burner off, turn the exhaust burner on based on a lower threshold temperature of the exhaust. The lower threshold temperature is less than the upper threshold temperature.
Multi-Tier Exhaust Burner Control For SCR Catalyst Pre-Heating
An exhaust control system for a vehicle includes a temperature sensor positioned downstream of an exhaust burner and upstream of an SCR catalyst in an exhaust system. The temperature sensor is configured to generate a measurement signal indicative a temperature of exhaust flowing through the exhaust system at an outlet of a DPF positioned downstream of the exhaust burner. An exhaust control module is configured to turn the exhaust burner on to heat the exhaust, monitor the temperature of the exhaust based on the measurement signal, subsequent to turning the exhaust burner on, turn the exhaust burner off based on an upper threshold temperature of the exhaust, and, subsequent to turning the exhaust burner off, turn the exhaust burner on based on a lower threshold temperature of the exhaust. The lower threshold temperature is less than the upper threshold temperature.