Abstract: A control apparatus for detecting a variation of a fluid level in a tank is disclosed. The control apparatus includes an Electronic Control Unit connected to the fluid level sensor. The ECU is configured to monitor a signal value representative of a fluid level in the tank; filter the fluid level signal value using a first filter to obtain a first filtered signal and using a second filter to obtain a second filtered signal, the first filter having a time constant (?1) lower than a time constant (?2) of the second filter; calculate an integral value of a difference between the first filtered signal and the second filtered signal; and generate a signal representative of the detection of an increase in the fluid level in the tank when the integral value is greater than a predefined threshold.

Abstract: A method of managing a selective catalytic reduction system of a motor vehicle. During a first predetermined time period, a plurality of functionality checks of the sensor are performed for identifying if the sensor is able to provide a reliable measurement of the ammonia concentration. During the same first predetermined time period, a plurality of values of the ammonia concentration in the diesel exhaust fluid is measured by the sensor. A maintenance inducement strategy of the selective catalytic reduction system is activated if each of the values of the ammonia concentration measured during the first predetermined time period is smaller than a predetermined threshold value, and if each of the functionality checks of the sensor performed during the same first predetermined time period identifies that the sensor is able to provide a reliable measurement of the ammonia concentration.

Abstract: A method for controlling an exhaust gas treatment system is provided. The exhaust gas treatment system includes an exhaust gas stream supplied by an exhaust gas source to a selective catalytic reduction device, and a reductant supply source utilizing a volumetric pump. The exhaust gas source can include an internal combustion engine (ICE), such as a gasoline or diesel ICE. The method for controlling an exhaust gas treatment system includes commanding a reductant dosing quantity, determining a volumetric pump energizing time, determining an energizing time correction, and energizing the pump. The volumetric pump can comprise pump logic, and the volumetric pump energizing time can be determined by the pump logic. The energizing time correction can be determined using a calibration table. The calibration table can prescribe an energizing time correction based on a current pump pressure and the commanded dosing quantity.

Abstract: An exhaust aftertreatment system includes first and second selective catalytic reduction devices (SCRs) and a single reductant injection system. A total ammonia storage capacity and an ammonia storage level are determined for the first and second SCRs, and determine a total SCR ammonia storage level for the first and second SCRs based upon the ammonia storage level on the first and second SCRs. A first storage error is determined, and a second storage error is determined based upon an ammonia storage level and an ammonia storage capacity for the second SCR. A second reductant dosing rate is determined based upon the second storage error. The reductant injection system injects reductant into the exhaust gas feedstream based upon the second reductant dosing rate when the second storage error indicates an imbalance between the ammonia storage on the first SCR and the ammonia storage on the second SCR.

Abstract: A method for monitoring the reductant quantity in a reservoir method is provided. The reductant is stored within the reservoir for use within an exhaust gas treatment system of a vehicle, and the reservoir comprises an acoustic sensor disposed within the reductant and capable of generating signals relating to the volume of reductant within the reservoir. The method includes generating a first signal for validation after a system wakeup, conducting a wakeup validation using a wakeup condition, wherein the wakeup condition includes determining if the first signal is within a first accuracy threshold relative to a validated signal generated during the previous operating cycle; and conducting a secondary validation for a signal generated after the first signal using one or more secondary validation conditions. The method can further comprise conducting one or more subsequent validations for one or more signals generated after the first signal.

Abstract: An exhaust aftertreatment system includes first and second selective catalytic reduction devices (SCRs) and a single reductant injection system. A total ammonia storage capacity and an ammonia storage level are determined for the first and second SCRs, and determine a total SCR ammonia storage level for the first and second SCRs based upon the ammonia storage level on the first and second SCRs. A first storage error is determined, and a second storage error is determined based upon an ammonia storage level and an ammonia storage capacity for the second SCR. A second reductant dosing rate is determined based upon the second storage error. The reductant injection system injects reductant into the exhaust gas feedstream based upon the second reductant dosing rate when the second storage error indicates an imbalance between the ammonia storage on the first SCR and the ammonia storage on the second SCR.

Abstract: A method for controlling an exhaust gas treatment system is provided. The exhaust gas treatment system includes an exhaust gas stream supplied by an exhaust gas source to a selective catalytic reduction device, and a reductant supply source utilizing a volumetric pump. The exhaust gas source can include an internal combustion engine (ICE), such as a gasoline or diesel ICE. The method for controlling an exhaust gas treatment system includes commanding a reductant dosing quantity, determining a volumetric pump energizing time, determining an energizing time correction, and energizing the pump. The volumetric pump can comprise pump logic, and the volumetric pump energizing time can be determined by the pump logic. The energizing time correction can be determined using a calibration table. The calibration table can prescribe an energizing time correction based on a current pump pressure and the commanded dosing quantity.

Abstract: A method for monitoring the reductant quantity in a reservoir method is provided. The reductant is stored within the reservoir for use within an exhaust gas treatment system of a vehicle, and the reservoir comprises an acoustic sensor disposed within the reductant and capable of generating signals relating to the volume of reductant within the reservoir. The method includes generating a first signal for validation after a system wakeup, conducting a wakeup validation using a wakeup condition, wherein the wakeup condition includes determining if the first signal is within a first accuracy threshold relative to a validated signal generated during the previous operating cycle; and conducting a secondary validation for a signal generated after the first signal using one or more secondary validation conditions. The method can further comprise conducting one or more subsequent validations for one or more signals generated after the first signal.

Abstract: A method for controlling an exhaust after-treatment system connected to a diesel engine via a gas passage and having a diesel oxidation catalyst (DOC) and a “diesel-exhaust-fluid” (DEF) injector arranged downstream of the DOC and upstream of a selective catalytic reduction catalyst (SCR) includes detecting a flow of exhaust gas emitted by the engine into the gas passage. The method also includes detecting a level of nitrogen oxides (NOx) in the exhaust gas downstream of the SCR. The method additionally includes activating the DEF injector for a period of time to reduce the level of NOx to a predetermined NOx value. Furthermore, the method includes regulating an injection of fuel upstream of the DOC to clean the DEF injector via a stream of superheated exhaust gas if the period of time used to reduce the level of NOx to the predetermined NOx value is greater than a predetermined threshold value.

Abstract: A method for controlling an exhaust after-treatment system connected to a diesel engine via a gas passage and having a diesel oxidation catalyst (DOC) and a “diesel-exhaust-fluid” (DEF) injector arranged downstream of the DOC and upstream of a selective catalytic reduction catalyst (SCR) includes detecting a flow of exhaust gas emitted by the engine into the gas passage. The method also includes detecting a level of nitrogen oxides (NOx) in the exhaust gas downstream of the SCR. The method additionally includes activating the DEF injector for a period of time to reduce the level of NOx to a predetermined NOx value. Furthermore, the method includes regulating an injection of fuel upstream of the DOC to clean the DEF injector via a stream of superheated exhaust gas if the period of time used to reduce the level of NOx to the predetermined NOx value is greater than a predetermined threshold value.

Abstract: A method of determining a thermal state or a thermal state transition of a substance based on how much liquid phase is available is disclosed. The method includes: (a) determining a current thermal state of the substance when the internal combustion engine is switched on based on a tank temperature and on a time interval during which the engine is switched off; and (b) calculating a percentage of the liquid phase in case the thermal state is a mixture of solid phase and liquid phase based on a total mass of the substance in the tank, a heat amount supplied to the tank, a heat exchange of the tank with an external environment; and (c) detecting the thermal state transitions based on said tank temperature and its time derivative and on said percentage of the liquid phase.

Abstract: A method of managing a selective catalytic reduction system of a motor vehicle. During a first predetermined time period, a plurality of functionality checks of the sensor are performed for identifying if the sensor is able to provide a reliable measurement of the ammonia concentration. During the same first predetermined time period, a plurality of values of the ammonia concentration in the diesel exhaust fluid is measured by the sensor. A maintenance inducement strategy of the selective catalytic reduction system is activated if each of the values of the ammonia concentration measured during the first predetermined time period is smaller than a predetermined threshold value, and if each of the functionality checks of the sensor performed during the same first predetermined time period identifies that the sensor is able to provide a reliable measurement of the ammonia concentration.

Abstract: A control apparatus is disclosed for a diesel exhaust fluid injector located in an exhaust pipe of a diesel internal combustion engine. The control apparatus includes an electronic control unit configured to: energize a solenoid of the injector to perform a diesel exhaust fluid injection; determine an electric voltage value indicative of the electric voltage applied to the injector solenoid during the diesel exhaust fluid injection; determine an electric current value indicative of the electric current flowing through the injector solenoid during the diesel exhaust fluid injection; calculate an electric resistance value of the injector solenoid as a function of the determined electric voltage value and the electric current value; and estimate an injector temperature value as a function of the calculated electric resistance value.

Abstract: A method for determining a fluid level value in a fluid tank of an internal combustion engine equipped with a discrete level sensor is provided. The discrete level sensor is configured for generating a first electrical signal when a fluid level is above or equal to a first predetermined fluid level threshold value and generating a second electrical signal when the fluid level is above or equal to a second predetermined fluid level threshold value. The second predetermined fluid level threshold value is greater than the first predetermined fluid level threshold value. The method includes monitoring a number of occurrences of the first electrical signal and of the second electrical signal over a time interval. The fluid level in the fluid tank is calculated as a function of the number of occurrences of the first and of the second electrical signals over the time interval.

Abstract: A control apparatus is disclosed for a diesel exhaust fluid injector located in an exhaust pipe of a diesel internal combustion engine. The control apparatus includes an electronic control unit configured to: energize a solenoid of the injector to perform a diesel exhaust fluid injection; determine an electric voltage value indicative of the electric voltage applied to the injector solenoid during the diesel exhaust fluid injection; determine an electric current value indicative of the electric current flowing through the injector solenoid during the diesel exhaust fluid injection; calculate an electric resistance value of the injector solenoid as a function of the determined electric voltage value and the electric current value; and estimate an injector temperature value as a function of the calculated electric resistance value.

Abstract: A control apparatus for detecting a variation of a fluid level in a tank is disclosed. The control apparatus includes an Electronic Control Unit connected to the fluid level sensor. The ECU is configured to monitor a signal value representative of a fluid level in the tank; filter the fluid level signal value using a first filter to obtain a first filtered signal and using a second filter to obtain a second filtered signal, the first filter having a time constant (?1) lower than a time constant (?2) of the second filter; calculate an integral value of a difference between the first filtered signal and the second filtered signal; and generate a signal representative of the detection of an increase in the fluid level in the tank when the integral value is greater than a predefined threshold.

Abstract: A method of determining a thermal state or a thermal state transition of a substance based on how much liquid phase is available is disclosed. The method includes: (a) determining a current thermal state of the substance when the internal combustion engine is switched on based on a tank temperature and on a time interval during which the engine is switched off; and (b) calculating a percentage of the liquid phase in case the thermal state is a mixture of solid phase and liquid phase based on a total mass of the substance in the tank, a heat amount supplied to the tank, a heat exchange of the tank with an external environment; and (c) detecting the thermal state transitions based on said tank temperature and its time derivative and on said percentage of the liquid phase.

Abstract: A method for determining a fluid level value in a fluid tank of an internal combustion engine equipped with a discrete level sensor is provided. The discrete level sensor is configured for generating a first electrical signal when a fluid level is above or equal to a first predetermined fluid level threshold value and generating a second electrical signal when the fluid level is above or equal to a second predetermined fluid level threshold value. The second predetermined fluid level threshold value is greater than the first predetermined fluid level threshold value. The method includes monitoring a number of occurrences of the first electrical signal and of the second electrical signal over a time interval. The fluid level in the fluid tank is calculated as a function of the number of occurrences of the first and of the second electrical signals over the time interval.

Abstract: A method is provided for operating a variable displacement oil pump of an internal combustion engine, that includes, but is not limited to measuring a value of an engine metal temperature and of preventing the variable displacement oil pump to switch from an high displacement configuration to a low displacement configuration, as long as the measured value is greater than a first threshold value of the engine metal temperature.