Abstract: An automotive vehicle includes an internal combustion engine and an exhaust system. The exhaust treatment system includes a dosing system that injects NH3 into an exhaust gas stream generated by the engine. An SCR device stores an amount of the NH3 and converts NOx into diatomic nitrogen (N2) and water (H2O) based on the stored amount of the NH3. The vehicle further includes an SCR status estimator device and a controller. The SCR status estimator device determines an NH3 coverage ratio (R), which indicates a stored amount of NH3 with respect to a maximum NH3 storage capacity of the SCR device. The controller determines a target NOx reduction efficiency (?NOx) of the SCR device, and an NH3 coverage ratio set point (Rsp) based on the ?NOx. The controller also generates an NH3 control signal (u) that controls the dosing system based on a comparison between the R and the Rsp.

Abstract: Disclosed are model predictive control (MPC) systems, methods for using such MPC systems, and motor vehicles with selective catalytic reduction (SCR) employing MPC control. An SCR-regulating MPC control system is disclosed that includes an NOx sensor for detecting nitrogen oxide (NOx) input received by the SCR system, catalyst NOx sensors for detecting NOx output for two SCR catalysts, and catalyst NH3 sensors for detecting ammonia (NH3) slip for each SCR catalyst. The MPC system also includes a control unit programmed to: receive desired can conversion efficiencies for the SCR catalysts; determine desired can NOx outputs for the SCR catalysts; determine maximum NH3 storage capacities for the SCR catalyst; calculate the current can conversion efficiency for each SCR catalyst; calculate an optimized reductant pulse-width and/or volume from the current can conversion efficiencies; and, command an SCR dosing injector to inject a reductant into an SCR conduit based on the calculated pulse-width/volume.

Abstract: Disclosed are model predictive control (MPC) systems, methods for using such MPC systems, and motor vehicles with selective catalytic reduction (SCR) employing MPC control. An SCR-regulating MPC control system is disclosed that includes an NOx sensor for detecting nitrogen oxide (NOx) input received by the SCR system, catalyst NOx sensors for detecting NOx output for two SCR catalysts, and catalyst NH3 sensors for detecting ammonia (NH3) slip for each SCR catalyst. The MPC system also includes a control unit programmed to: receive desired can conversion efficiencies for the SCR catalysts; determine desired can NOx outputs for the SCR catalysts; determine maximum NH3 storage capacities for the SCR catalyst; calculate the current can conversion efficiency for each SCR catalyst; calculate an optimized reductant pulse-width and/or volume from the current can conversion efficiencies; and, command an SCR dosing injector to inject a reductant into an SCR conduit based on the calculated pulse-width/volume.

Abstract: Disclosed are model predictive control (MPC) systems, methods for using such MPC systems, and motor vehicles with selective catalytic reduction (SCR) employing MPC control. An SCR-regulating MPC control system is disclosed that includes an NOx sensor for detecting nitrogen oxide (NOx) input received by the SCR system, catalyst NOx sensors for detecting NOx output for two SCR catalysts, and catalyst NH3 sensors for detecting ammonia (NH3) slip for each SCR catalyst. The MPC system also includes a control unit programmed to: receive desired can conversion efficiencies for the SCR catalysts; determine desired can NOx outputs for the SCR catalysts; determine maximum NH3 storage capacities for the SCR catalyst; calculate the current can conversion efficiency for each SCR catalyst; calculate an optimized reductant pulse-width and/or volume from the current can conversion efficiencies; and, command an SCR dosing injector to inject a reductant into an SCR conduit based on the calculated pulse-width/volume.

Abstract: A method is disclosed for evaluating a soot quantity accumulated in a Selective Catalytic Reduction wash-coated particulate filter of an internal combustion engine. The internal combustion engine is equipped with an exhaust gas aftertreatment system including an urea injector. Using a map correlating a urea quantity value, a NOx quantity value, a temperature value and a mass flow value to a correction value of a soot quantity is used to correct an estimated value of the soot quantity in order to obtain an evaluated value of the soot quantity.

Abstract: A system includes a target generating module, a model predictive control (MPC) module, and an actuator module. The target generating module generates a target value for an actuator of an engine. The MPC module generates a set of possible adjustments to the target value and predicts an operating parameter for the set of possible adjustments. The predicted operating parameter includes an emission level and/or an operating parameter of an exhaust system. The MPC module determines a cost for the set of possible adjustments and selects the set of possible adjustments from multiple sets of possible adjustments based on the cost. The MPC module determines whether the predicted operating parameter for the selected set satisfies a constraint and adjusts the target value using the possible adjustments of the selected set when the predicted operating parameter satisfies the constraint. The actuator module controls the actuator based on the target value as adjusted.

Abstract: A method is disclosed for controlling an injector for injecting a reductant into a selective catalytic reduction system of an internal combustion engine. A value of a concentration of nitrogen-oxides in the exhaust gas aftertreatment system downstream of the selective catalytic reduction system is measured, and a first difference is calculated between the measured value of the nitrogen-oxides concentration and a predetermined reference value thereof. A value of a concentration of ammonia in the exhaust gas aftertreatment system downstream of the selective catalytic reduction system is measured, and a second difference is calculated between the measured value of the ammonia concentration and a predetermined reference value thereof. A quantity of reductant to be injected by the injector is calculated as a function of the calculated first difference and second difference, and the injector is operated to inject the calculated quantity of reductant.

Abstract: An internal combustion engine fluidly coupled to an exhaust aftertreatment system includes a particulate filter device, a first selective catalytic reduction device disposed upstream relative to a second selective catalytic reduction device, and an injection system disposed to inject a reductant into the exhaust gas feedstream upstream relative to the first selective catalytic reduction device. A method for controlling the internal combustion engine includes monitoring engine operation, and determining an amount of particulate matter stored on the particulate filter based thereon. An amount of reductant stored on the second selective catalytic reduction device and operating conditions associated with the exhaust aftertreatment system are also determined.

Abstract: An exhaust system for a lean-burn internal combustion engine is described, and includes an injection system for injecting reductant into an exhaust gas feedstream upstream of a selective catalytic reduction device (SCR). A control method for controlling the injection system includes determining an upstream NOx gas concentration upstream of the SCR device, determining a measured downstream NOx gas concentration based upon a signal output from a sensor configured to monitor NOx gas concentration downstream of the SCR device, and determining an estimated downstream NOx gas concentration based upon an executable model. A first correlation between the upstream NOx gas concentration and the measured downstream NOx gas concentration is determined, and a second correlation between the upstream NOx gas concentration and the estimated downstream NOx gas concentration is determined. The reductant injection is controlled based upon the first and second correlations.

Abstract: An internal combustion engine fluidly coupled to an exhaust aftertreatment system includes a particulate filter device, a first selective catalytic reduction device disposed upstream relative to a second selective catalytic reduction device, and an injection system disposed to inject a reductant into the exhaust gas feedstream upstream relative to the first selective catalytic reduction device. A method for controlling the internal combustion engine includes monitoring engine operation, and determining an amount of particulate matter stored on the particulate filter based thereon. An amount of reductant stored on the second selective catalytic reduction device and operating conditions associated with the exhaust aftertreatment system are also determined.

Abstract: An internal combustion engine is coupled to an oxidation catalyst disposed upstream of a second catalytic device. A controller includes an instruction set executable to detect a cold start engine starting event, monitor first and second temperature sensors, control each of the fuel injectors to execute a first set of fuel injection events for each cylinder event in response to an output torque request, and execute a second set of fuel injection events for each cylinder event after cylinder top-dead-center. The second set of fuel injection events includes a final injection event, and a duration of the final injection event is determined based upon the first and second temperatures.

Abstract: A system includes a target generating module, a model predictive control (MPC) module, and an actuator module. The target generating module generates a target value for an actuator of an engine. The MPC module generates a set of possible adjustments to the target value and predicts an operating parameter for the set of possible adjustments. The predicted operating parameter includes an emission level and/or an operating parameter of an exhaust system. The MPC module determines a cost for the set of possible adjustments and selects the set of possible adjustments from multiple sets of possible adjustments based on the cost. The MPC module determines whether the predicted operating parameter for the selected set satisfies a constraint and adjusts the target value using the possible adjustments of the selected set when the predicted operating parameter satisfies the constraint. The actuator module controls the actuator based on the target value as adjusted.

Abstract: An exhaust system for a lean-burn internal combustion engine is described, and includes an injection system for injecting reductant into an exhaust gas feedstream upstream of a selective catalytic reduction device (SCR). A control method for controlling the injection system includes determining an upstream NOx gas concentration upstream of the SCR device, determining a measured downstream NOx gas concentration based upon a signal output from a sensor configured to monitor NOx gas concentration downstream of the SCR device, and determining an estimated downstream NOx gas concentration based upon an executable model. A first correlation between the upstream NOx gas concentration and the measured downstream NOx gas concentration is determined, and a second correlation between the upstream NOx gas concentration and the estimated downstream NOx gas concentration is determined. The reductant injection is controlled based upon the first and second correlations.

Abstract: A method of controlling a particulate filter of an internal combustion engine is disclosed. A regeneration cycle of the particulate filter is initiated. During the regeneration, a value of an exhaust gas temperature at an outlet of the particulate filter is determined and a value of a residual soot quantity stored into the particulate filter is estimated on the basis of the measured value of the exhaust gas temperature at the outlet of the particulate filter. The regeneration cycle may be started and stopped based on the estimated residual soot quantity.

Abstract: A method of operating a Selective Catalytic Reduction on Diesel Particulate Filter or SDPF is disclosed. During a SDPF regeneration; temperature values are obtained for the SDPF inlet and SDPF outlet. The temperature values are used to calculate a rate of increase of SDPF outlet temperature and a rate of increase of SDPF inlet temperature. A ratio between the rate of increase of SDPF outlet temperature values and the rate of increase of SDPF inlet temperature values is calculated, and if the ratio is greater than a threshold thereof, the exhaust gas composition is modified in some manner.

Abstract: A method is disclosed for evaluating a soot quantity accumulated in a Selective Catalytic Reduction wash-coated particulate filter of an internal combustion engine. The internal combustion engine is equipped with an exhaust gas aftertreatment system including an urea injector. Using a map correlating a urea quantity value, a NOx quantity value, a temperature value and a mass flow value to a correction value of a soot quantity is used to correct an estimated value of the soot quantity in order to obtain an evaluated value of the soot quantity.