Abstract: A selective catalytic reduction (SCR) system includes a first sensor that determines a first concentration of NOx, a second sensor that determines a second concentration of NOx and NH3, and a fault determination module. The fault determination module diagnoses a fault in at least one of a dosing agent and a catalyst in an SCR device based on the first and second concentrations.

Abstract: A control system for a selective catalytic reduction (SCR) system includes a dosing control module, a comparison module, and a status determination module. The dosing control module controls a dosing system to inject a desired amount of ammonia into exhaust gas at a first location in an exhaust stream. The comparison module compares a measured amount of ammonia in the exhaust gas to the desired amount of ammonia, wherein the measured amount of ammonia is measured at a second location downstream from the first location and upstream from or within an SCR catalyst. The status determination module determines a pass/fail status of a component of the dosing system based on the comparison between the measured amount of ammonia and the desired amount of ammonia.

Abstract: An exhaust gas treatment system includes a SCR device that stores a reductant that reacts with the NOx emissions and a reductant supply system to inject the reductant according to a reductant load model. At least one temperature sensor or model generates a temperature signal indicating an SCR temperature of the SCR device. The exhaust gas treatment system further includes a control module in electrical communication with the reductant supply system. The control module is configured to determine an amount of reductant that slips from the SCR device based on the at least one temperature signal and the rate of change of the SCR temperature. The control module further determines a correction factor based on the amount of slipped reductant to modify the reductant load model.

Abstract: A method of regenerating a particulate filter of an exhaust system is provided. The method includes determining a first regeneration mode based on a soot level; generating control signals to a first fuel injector associated with an engine based on the first regeneration mode; determining a second regeneration mode based on the soot level; and generating control signal to a second fuel injector associated with an exhaust stream of the exhaust system based on the second regeneration mode.

Abstract: An exhaust gas treatment system includes a SCR device that stores a reductant that reacts with the NOx emissions and a reductant supply system to inject the reductant according to a reductant load model. At least one temperature sensor or model generates a temperature signal indicating an SCR temperature of the SCR device. The exhaust gas treatment system further includes a control module in electrical communication with the reductant supply system. The control module is configured to determine an amount of reductant that slips from the SCR device based on the at least one temperature signal and the rate of change of the SCR temperature. The control module further determines a correction factor based on the amount of slipped reductant to modify the reductant load model.

Abstract: An apparatus and method of controlling a vehicle aftertreatment system is provided. The aftertreatment system treats exhaust gas produced by the vehicle engine and includes a particulate filter, and a NOx reducing device such as a selective catalytic reduction (SCR) device. The particulate filter is configured to regenerate to remove accumulated particles when the exhaust gas is heated above a regeneration temperature. A diagnostic device is included for monitoring the aftertreatment system. The diagnostic device may be a sensor for measuring the oxides of nitrogen (NOx) and/or an SCR efficiency monitor. A controller is employed to optimize the function of the diagnostic device. The controller does not enable the diagnostic device when the vehicle is powered until one or more entry conditions are satisfied.

Abstract: A tank assembly includes a tank defining a chamber that is configured to store a selectively variable volume of liquid. A positive temperature coefficient heater is disposed within the chamber. A source of electrical energy is in selective electrical communication with the heater and is configured to transfer electrical current to the heater. A controller is operatively connected to the heater and is configured to monitor the amount of electrical current to the heater. The controller is programmed to determine the volume of liquid in the chamber based on the amount of current transferred to the heater.

Abstract: A method of determining aging of a diesel oxidation catalyst (DOC) in an engine exhaust system includes receiving a first sensor signal from a first nitrogen oxides (NOx) sensor positioned in exhaust flow upstream of the DOC. The first sensor signal is indicative of an amount of NOx in the exhaust flow upstream of the DOC. The method further includes receiving a second sensor signal from a second NOx sensor positioned in the exhaust flow downstream of the DOC. The second sensor signal is indicative of an amount of NOx downstream of the DOC. A difference between the first sensor signal and the second sensor signal is calculated by a controller. A DOC aging level based on a predetermined correlation between the difference and DOC aging can then be determined by the controller if at least one predetermined operating condition is satisfied.

Abstract: A method of determining aging of a diesel oxidation catalyst (DOC) in an engine exhaust system includes receiving a first sensor signal from a first nitrogen oxides (NOx) sensor positioned in exhaust flow upstream of the DOC. The first sensor signal is indicative of an amount of NOx in the exhaust flow upstream of the DOC. The method further includes receiving a second sensor signal from a second NOx sensor positioned in the exhaust flow downstream of the DOC. The second sensor signal is indicative of an amount of NOx downstream of the DOC. A difference between the first sensor signal and the second sensor signal is calculated by a controller. A DOC aging level based on a predetermined correlation between the difference and DOC aging can then be determined by the controller if at least one predetermined operating condition is satisfied.

Abstract: An apparatus and method of controlling a vehicle aftertreatment system is provided. The aftertreatment system treats exhaust gas produced by the vehicle engine and includes a particulate filter, and a NOx reducing device such as a selective catalytic reduction (SCR) device. The particulate filter is configured to regenerate to remove accumulated particles when the exhaust gas is heated above a regeneration temperature. A diagnostic device is included for monitoring the aftertreatment system. The diagnostic device may be a sensor for measuring the oxides of nitrogen (NOx) and/or an SCR efficiency monitor. A controller is employed to optimize the function of the diagnostic device. The controller does not enable the diagnostic device when the vehicle is powered until one or more entry conditions are satisfied.

Abstract: A control module for a vehicle includes a correction module that generates a correction signal based on a regeneration state of an exhaust system of the vehicle and based on a received environmental signal. The environmental signal includes at least one of an altitude value, an ambient temperature, and an air flow value. The air flow value corresponds to air flow across an external area of the exhaust system. A first post injection module generates a first post injection signal. A second post injection module adjusts the first post injection signal based on the correction signal to generate a second post injection signal.

Abstract: A dosing control system for a vehicle includes a current storage module, an adaption triggering module, and an adaption ending module. The current storage module estimates an amount of ammonia stored by a selective catalytic reduction (SCR) catalyst. The adaptation triggering module triggers a reduction of the amount of ammonia stored by the SCR catalyst to zero when a first amount of nitrogen oxides (NOx) measured by a first NOx sensor located downstream of the SCR catalyst is greater than a predicted value of the first amount of NOx. The adaptation ending module selectively ends the reduction and enables injection of dosing agent based on a comparison of the first amount of NOx with a second amount of NOx upstream of the SCR catalyst.

Abstract: A dosing control system for a vehicle includes an adaption triggering module, a dosing management module, and an adaption ending module. The adaptation triggering module triggers performance of an adaptation event when a first amount of nitrogen oxides (NOx) measured by a first NOx sensor located downstream of a selective catalytic reduction (SCR) catalyst is greater than a predicted value of the first amount of NOx. The dosing management module disables dosing agent injection during the adaptation event. The adaptation ending module selectively delays ending the adaptation event after a predetermined number of phases of the adaption event have been completed based on a comparison of the first amount of NOx with a second amount of NOx measured by a second NOx sensor located upstream of the SCR catalyst.

Abstract: A temperature control system comprises a temperature determination module, a temperature correction module, a temperature control module, and an updating module. The temperature determination module determines a desired outlet temperature for an oxidation catalyst (OC) that is located upstream of a particulate filter (PF) in an exhaust system. The temperature correction module determines a temperature correction from a plurality of temperature corrections. The temperature control module controls an outlet temperature of the OC based on the desired outlet temperature and the temperature correction. The updating module selectively updates at least one of the plurality of temperature corrections when an engine speed and an engine load are within respective predetermined ranges.

Abstract: A method of regenerating a particulate filter of an exhaust system is provided. The method includes determining a first regeneration mode based on a soot level; generating control signals to a first fuel injector associated with an engine based on the first regeneration mode; determining a second regeneration mode based on the soot level; and generating control signal to a second fuel injector associated with an exhaust stream of the exhaust system based on the second regeneration mode.

Abstract: An engine control system includes a temperature determination module, a reducing agent control module, and a control module. The temperature determination module determines a temperature of a reducing agent injector heated by an exhaust gas. The reducing agent control module actuates the reducing agent injector to inject an amount of reducing agent into the exhaust gas when the temperature is greater than or equal to a temperature threshold. The control module controls a concentration of nitrogen oxides in the exhaust gas based on the amount of reducing agent injected into the exhaust gas.

Abstract: A treatment control system comprises a monitoring module and an injection control module. The monitoring module monitors an exhaust temperature and an exhaust flow rate in an exhaust system of a vehicle. The injection control module controls injection of a dosing agent into the exhaust system for first and second regeneration events of a diesel particulate filter (DPF) and selectively injects a predetermined amount of the dosing agent into the exhaust system between the first and second regeneration events when the exhaust temperature is greater than a predetermined temperature and the exhaust flow rate is greater than a predetermined flow rate.

Abstract: A control system for a selective catalytic reduction (SCR) system includes a dosing control module, a comparison module, and a status determination module. The dosing control module controls a dosing system to inject a desired amount of ammonia into exhaust gas at a first location in an exhaust stream. The comparison module compares a measured amount of ammonia in the exhaust gas to the desired amount of ammonia, wherein the measured amount of ammonia is measured at a second location downstream from the first location and upstream from or within an SCR catalyst. The status determination module determines a pass/fail status of a component of the dosing system based on the comparison between the measured amount of ammonia and the desired amount of ammonia.

Abstract: A system comprises an injection control module and a fuel film module. The injection control module controls a flow rate of fuel injected into an exhaust system to adjust a temperature of exhaust gas. The fuel film module determines an accumulation rate of fuel on a surface of the exhaust system based on the flow rate of the fuel. The fuel film module determines a release rate of fuel from the surface of the exhaust system based on a flow rate of the exhaust gas. The injection control module adjusts the flow rate of the fuel based on the accumulation rate and the release rate.

Abstract: A tank assembly includes a tank defining a chamber that is configured to store a selectively variable volume of liquid. A positive temperature coefficient heater is disposed within the chamber. A source of electrical energy is in selective electrical communication with the heater and is configured to transfer electrical current to the heater. A controller is operatively connected to the heater and is configured to monitor the amount of electrical current to the heater. The controller is programmed to determine the volume of liquid in the chamber based on the amount of current transferred to the heater.