Abstract: A system includes an exhaust treatment system configured to treat emissions from a combustion engine via a catalyst. The system includes a controller configured to obtain an operating parameter indicating catalyst performance. The controller is configured to determine a deterioration factor indicating deterioration of the catalyst based at least in part on the operating parameter. The controller is configured to determine an adaptation term configured to modify an air-fuel ratio command for the combustion engine to account for the deterioration.

Abstract: A method for diagnosing a waste gate valve malfunction in a power generation system is presented. The method includes determining an actual pressure differential across a throttle valve. The method further includes determining an estimated pressure differential across the throttle valve based on one or more first operating parameters of the power generation system. Furthermore, the method includes determining an absolute difference between the actual pressure differential and the estimated pressure differential. Moreover, the method also includes comparing the absolute difference with a threshold value and if the absolute difference is greater than the threshold value, determining an operating condition of the throttle valve. Additionally, the method includes determining whether the waste gate valve has malfunctioned based on the determined operating condition of the throttle valve. An engine controller and a power generation system employing the method are also presented.

Abstract: A system includes a controller that has a processor configured to receive a first signal from a first oxygen sensor indicative of a first oxygen measurement, wherein the first oxygen sensor is disposed upstream of a catalytic converter system; and to receive a second signal from a second oxygen sensor indicative of a second oxygen measurement, wherein the second oxygen sensor is disposed downstream of the catalytic converter system; and to execute a catalyst estimator system, wherein the catalyst estimator system is configured to derive an oxygen storage estimate based on the first signal, the second signal, and a catalytic converter model. The processor is configured to derive a system oxygen storage setpoint for the catalytic converter system based on the catalytic converter model and the oxygen storage estimate.

Abstract: A system includes an engine comprising an EGR valve that recirculates a portion of exhaust gas, a data repository that stores a first look up and one or more engine operational parameters, an engine control unit operationally coupled to the engine and the data repository, wherein the engine control unit is configured to: determine a desired EGR flow rate reference of the portion of the exhaust gas based on the one or more engine operational parameters and the first look up table, determine a current estimated EGR flow rate based on the one or more engine operational parameters, determine a designated corrected EGR flow rate reference based on the desired EGR flow rate reference and a delta EGR flow rate, determine EGR flow rate error, and determine a percentage opening of the EGR valve based at least on the EGR flow rate error.

Abstract: A system includes a nitrogen oxide reduction catalyst fluidly coupled to an exhaust conduit of an engine system. The nitrogen oxide reduction catalyst is configured to reduce nitrogen oxides in an engine exhaust. The system also includes an ammonia oxidation catalyst fluidly coupled to the exhaust conduit downstream of the nitrogen oxide reduction catalyst and configured to reduce ammonia in the engine exhaust. Further, the system includes a reductant injection control system configured to control an injection of reductant into the exhaust conduit, determine a first nitrogen oxide conversion rate of the nitrogen oxide reduction catalyst, determine an ammonia storage value of the nitrogen oxide reduction catalyst, and determine a first temperature of the engine exhaust upstream of the ammonia oxidation catalyst.

Abstract: A system includes a controller programmed to monitor an NH3 storage state of a selective catalytic reduction (SCR) catalyst. The controller is programmed to receive signals representative of NH3 and/or NOX concentrations in a fluid both upstream of an inlet and downstream of an outlet of the SCR catalyst, to receive a signal representative of the measured NH3 storage of the SCR catalyst from at least one RF probe disposed within the SCR catalyst, to utilize a model to generate an estimated NH3 storage of the SCR catalyst based at least on the NH3 and/or NOX concentrations in the fluid both upstream and downstream of the SCR catalyst, to compare the estimated NH3 storage to the measured NH3 storage, and to output a control action for the SCR catalyst based at least on the comparison of the estimated NH3 storage to the measured NH3 storage.

Abstract: A system includes a controller programmed to determine an oxidation state of a three-way catalyst (TWC) assembly based on a first signal representative of a measured oxygen (O2) storage of the TWC assembly received from a radio frequency (RF) probe disposed within the TWC assembly, to determine whether a temperature of a fluid flowing into an ammonia slip catalyst (ASC) assembly is within a desired temperature operating range based on a second signal representative of the temperature of the fluid adjacent an inlet of the ASC assembly, to determine whether a concentration of nitrogen oxides (NOX) in the fluid exiting an outlet of the ASC assembly is within desired limits based on a third signal representative of the concentration of NOX in the fluid, and to determine whether to perform diagnostics on a component of an exhaust aftertreatment system based at least on the first, second, and third signals.

Abstract: A system includes a controller programmed to monitor an oxidation state of a three-way catalyst (TWC) assembly coupled to a combustion engine. The controller is programmed to receive signals representative of oxygen (O2) concentration in a fluid both upstream of an inlet and downstream of an outlet of the TWC assembly, to receive a signal representative of the measured O2 storage of the TWC assembly from at least one radio frequency (RF) probe disposed within the TWC assembly, to utilize a model to generate an estimated O2 storage of the TWC assembly based at least on the O2 concentration in the fluid both upstream and downstream of the TWC assembly, to compare the estimated O2 storage to the measured O2 storage, and to output a control action for the TWC assembly based at least on the comparison of the estimated O2 storage to the measured O2 storage.

Abstract: A system includes a nitrogen oxide reduction catalyst fluidly coupled to an exhaust conduit of an engine system. The nitrogen oxide reduction catalyst is configured to reduce nitrogen oxides in an engine exhaust. The system also includes an ammonia oxidation catalyst fluidly coupled to the exhaust conduit downstream of the nitrogen oxide reduction catalyst and configured to reduce ammonia in the engine exhaust. Further, the system includes a reductant injection control system configured to control an injection of reductant into the exhaust conduit, determine a first nitrogen oxide conversion rate of the nitrogen oxide reduction catalyst, determine an ammonia storage value of the nitrogen oxide reduction catalyst, and determine a first temperature of the engine exhaust upstream of the ammonia oxidation catalyst.

Abstract: A system includes an exhaust aftertreatment system configured to treat emissions from a combustion engine. The exhaust aftertreatment system includes a selective catalytic reduction (SCR) catalyst assembly and at least one radio frequency (RF) probe disposed within the SCR catalyst assembly. A controller is coupled to the exhaust aftertreatment system and utilizes an NH3 storage estimate measured by the at least one RF probe and an NH3 storage estimate determined by an NH3 storage estimate model to output a control action for a reductant injection system. The NH3 storage estimate model utilizes measured concentrations of nitrogen oxides (NOx) in the fluid upstream or downstream of the SCR catalyst and/or measured concentrations of NH3 in the fluid upstream or downstream of the SCR catalyst, and the NH3 storage measurement from the at least one RF probe to determine the NH3 storage estimate.

Abstract: Various embodiments include systems adapted to monitor catalyst deterioration. Some embodiments include a catalyst deterioration detection system including a pre-catalytic converter gas sensor, a post-catalytic converter gas sensor, at least one computing device in communication with the pre-catalytic converter and post-catalytic converter gas sensors, the at least one computing device configured to monitor catalyst deterioration by performing actions including estimating a catalyst gas storage level by comparing a difference between a pre-catalytic converter gas level from the pre-catalytic converter gas sensor and a post-catalytic converter gas level from the post-catalytic converter gas sensor, comparing the estimated catalyst gas storage level to a baseline catalyst gas storage level and determining that the catalyst is deteriorated in response to the baseline catalyst gas storage level exceeding the estimated gas storage level by a threshold difference.

Abstract: A system includes a controller configured to compare a nitrogen oxides (NOX) concentration within treated exhaust gases from a combustion engine after flowing through a first catalyst assembly and a second catalyst assembly relative to a NOX threshold value, to determine a change in O2 concentration within the treated exhaust gases between the first and second catalyst assemblies upstream of a location of oxidant injection into the treated exhaust gases, and to adjust an air-fuel ratio of the combustion engine based on the change in O2 concentration in the treated exhaust gases if the NOX concentration is greater than the NOX threshold value.

Abstract: A system includes a controller configured to compare a nitrogen oxides (NOX) concentration within treated exhaust gases from a combustion engine after flowing through a first catalyst assembly and a second catalyst assembly relative to a NOX threshold value, to determine a change in O2 concentration within the treated exhaust gases between the first and second catalyst assemblies upstream of a location of oxidant injection into the treated exhaust gases, and to adjust an air-fuel ratio of the combustion engine based on the change in O2 concentration in the treated exhaust gases if the NOX concentration is greater than the NOX threshold value.

Abstract: A system includes a controller that has a processor configured to receive a first signal from a first oxygen sensor indicative of a first oxygen measurement, wherein the first oxygen sensor is disposed upstream of a catalytic converter system; and to receive a second signal from a second oxygen sensor indicative of a second oxygen measurement, wherein the second oxygen sensor is disposed downstream of the catalytic converter system; and to execute a catalyst estimator system, wherein the catalyst estimator system is configured to derive an oxygen storage estimate based on the first signal, the second signal, and a catalytic converter model. The processor is configured to derive a system oxygen storage setpoint for the catalytic converter system based on the catalytic converter model and the oxygen storage estimate.

Abstract: A system includes a controller that has a processor. The processor is configured to receive a first signal from a first oxygen sensor indicative of a first oxygen measurement and a second signal from a second oxygen sensor indicative of a second oxygen measurement. The first oxygen sensor is disposed upstream of a catalytic converter system and the second oxygen sensor is disposed downstream of the catalytic converter system. The processor is also configured to derive a plurality of oxygen storage estimates based on the first signal, the second signal, and a catalytic converter model. Each of the plurality of oxygen storage estimates represents an oxygen storage estimate for a corresponding cell of a plurality of cells in the catalytic converter system. Further, the processor is configured to derive a system oxygen storage estimate for the catalytic converter system based on the plurality of oxygen storage estimates.

Abstract: A system includes an exhaust aftertreatment system configured to treat emissions from a combustion engine. The exhaust aftertreatment system includes a first catalyst assembly having an outlet. The exhaust aftertreatment system also includes an ammonia slip catalyst (ASC) assembly configured to receive a fluid from the first catalyst assembly and to convert ammonia (NH3) within the fluid into nitrogen (N2), wherein the ASC assembly has an inlet. The exhaust aftertreatment system further includes a silencer disposed between the outlet of the first catalyst assembly and the inlet of the ASC assembly, wherein the silencer is configured to receive the fluid and an oxidant for mixing with the fluid provide sufficient oxygen in the fluid flowing into the inlet of the ASC assembly to enable the catalytic activity in the ASC assembly that coverts NH3 into N2, and the silencer is configured to mix the fluid and the oxidant.

Abstract: A system includes an exhaust aftertreatment system configured to treat emissions from a combustion engine. The exhaust aftertreatment system includes a first catalyst assembly having an outlet. The exhaust aftertreatment system also includes an ammonia slip catalyst (ASC) assembly configured to receive a fluid from the first catalyst assembly and to convert ammonia (NH3) within the fluid into nitrogen (N2), wherein the ASC assembly has an inlet. The exhaust aftertreatment system further includes a silencer disposed between the outlet of the first catalyst assembly and the inlet of the ASC assembly, wherein the silencer is configured to receive the fluid and an oxidant for mixing with the fluid provide sufficient oxygen in the fluid flowing into the inlet of the ASC assembly to enable the catalytic activity in the ASC assembly that coverts NH3 into N2, and the silencer is configured to mix the fluid and the oxidant.

Abstract: A system includes a controller. The controller is configured to monitor a catalytic activity within an ASC assembly that converts ammonia (NH3) within a fluid received from a three-way catalyst (TWC) assembly into nitrogen (N2) to determine whether the catalytic activity in the ASC assembly has aged. The controller is configured to adjust a temperature of the fluid flowing into an inlet of the ASC assembly by controlling an amount of oxidant injected via an oxidant injection system into the fluid upstream of the inlet of the ASC assembly based on a determination that the catalytic activity in the ASC assembly has aged.

Abstract: A gaseous reductant injection control system for exhaust aftertreatment is disclosed. In one embodiment, a selective catalytic reduction (SCR) catalyst is in fluid communication with an exhaust stream generated from an engine. An oxidation catalyst (OC) is upstream of the SCR catalyst and in fluid communication with the exhaust stream. A gaseous reductant injector is upstream of the SCR catalyst and downstream of the OC and in fluid communication with the exhaust stream. A first gas sensor is upstream of the OC and a second gas sensor is downstream of the SCR catalyst. A controller receives signals representative of gas concentrations detected in the exhaust stream by the first gas sensor and the second gas sensor, and estimates concentrations of nitric oxide (NO) and nitride dioxide (NO2) in the exhaust stream therefrom.

Abstract: A system includes a controller configured to determine if a combustion engine is operating under a desired rich fuel condition. The controller is also configured, if the combustion engine is operating under the desired rich fuel condition, to monitor a catalytic activity within an ASC assembly that converts NH3 within treated exhaust gases from the combustion engine into N2 to determine whether the catalytic activity has been deactivated in the ASC assembly.