Gm Global Technolgoy Operations, Inc.

Christopher C Swoish

Christopher L Whitt

Thomas LaRose, Jr

Douglas Christopher Sarsen

Joshua Clifford Bedford

Justin Adam Shetney

Rebecca J Darr

A particulate filter device monitoring system for an engine includes a regeneration mode trigger module configured to set a regeneration request based on soot accumulation in the particulate filter device, a regeneration control module configured to control regeneration of the particulate filter device, and a soot out model module including a soot out model configured to calculate changes in soot out rate during prolonged engine idling periods.

Particulate filter device monitoring system for an engine

An exhaust treatment system includes an SCRF device, a reductant delivery system, and an SCR storage module. The SCRF device includes a filter portion having a washcoat formed thereon that defines a washcoat thickness (WCT). The reductant delivery system is configured to inject a reductant that reacts with the washcoat based on a reductant storage model. The SCR storage module is in electrical communication with the reductant delivery system to provide the reductant storage model the amount of reductant to be injected based on the reductant storage model. The exhaust treatment system further includes a WCT compensation module configured to electrically communicate a WCT compensation value to the SCR storage module. The SCR storage module modifies the reductant storage model according to the WCT compensation value such that the amount of ammonia that slips from the SCRF device is reduced thereby increasing a storage efficiency of the SCRF device.

SCR filter washcoat thickness efficiency compensation system

An internal combustion engine is fluidly coupled to an exhaust aftertreatment system including a particulate filter. A method for operating the internal combustion engine includes determining an expected boost pressure of an intake air compressor system in response to an output torque request, determining a deviation between an actual boost pressure and the expected boost pressure, determining a engine-out soot generation rate correction based upon the deviation between the actual boost pressure and the expected boost pressure, adjusting a steady-state engine-out soot generation rate using the engine-out soot generation rate correction, time-integrating the adjusted steady-state engine-out soot generation rate, and commanding regeneration of the particulate filter when the time-integrated adjusted engine-out soot generation rate exceeds a predetermined threshold.

Method and apparatus to control regeneration of a particulate filter

A particulate filter device monitoring system for an internal combustion engine includes a particulate accumulation register configured to store an amount of particulate in a particulate filter. The particulate accumulation register includes a particulate accumulation trigger zone having a power limiting mode trigger. A power limiting mode trigger module is configured to limit output power of the internal combustion engine when the amount of particulate accumulation reaches the power limiting mode trigger. A particulate accumulation model module includes a particulate accumulation model configured to calculate changes in particulate accumulation in the particulate accumulation register at a first sampling rate when particulate accumulation is outside the particulate accumulation trigger zone, and at a second sampling rate when particulate accumulation is within the particulate accumulation trigger zone.

Particulate filter device monitoring system for an internal combustion engine

A method of monitoring a particulate filter of an exhaust aftertreatment device includes sensing a first pressure drop across the particulate filter at a first instant in time, and sensing a second pressure drop across the particulate filter at a second instant in time. A controller may then calculate a rate-of-change of the pressure drop between the first instant in time and the second instant in time while sensing a flow rate of an exhaust gas flowing through the exhaust aftertreatment device. Using the sensed exhaust flow rate, the controller may determine a rate-of-change threshold, and subsequently compare the calculated rate-of-change to the rate-of-change threshold. The method further includes updating a soot model using the sensed second pressure drop if the calculated rate-of-change is less than the rate-of-change threshold.

System and method for monitoring a particulate filter in a vehicle exhaust aftertreatment device

A vehicle and a method of updating efficiency of a selective catalytic reduction filter (SCRF) of an exhaust treatment system of the vehicle are disclosed. The method includes obtaining an initial calculated efficiency of the SCRF, via a controller, regarding one of a NOx conversion, a reductant absorption, a reductant desorption and a reductant oxidation. The method also includes determining a soot mass estimate in the SCRF representative of an amount of soot collected inside the SCRF and determining a soot correction factor from the soot mass estimate. The method further includes calculating, via the controller, an updated efficiency value of the SCRF by multiplying the soot correction factor and the initial calculated efficiency to update efficiency of the SCRF.

Vehicle and a method of updating efficiency of a selective catalytic reduction filter of an exhaust treatment system of the vehicle

A urea injection controller for a motorized system includes a passive regeneration model configured and disposed to calculate an amount of NOx conversion resulting from an interaction between exhaust gases and soot entrained in a selective catalyst reduction filter (SCRF) device, a replenishment mode trigger module configured to set an ammonia replenishment request based on the passive regeneration model, and a replenishment control module configured to selectively activate a urea injector to discharge a particular amount of urea based on the regeneration model.

Urea injection controller for a motorized system

An exhaust treatment system to treat exhaust gas includes a particulate filter and a pressure sensor. The particulate filter is configured to trap soot contained in exhaust gas. The pressure sensor is configured to output a pressure signal indicative of a pressure differential of the particulate filter. The exhaust treatment system further includes a soot mass module configured to determine a soot mass. The soot mass is indicative of an amount of soot stored in the particulate filter based on the pressure differential and a soot model stored in a memory device. The exhaust treatment system further includes a continuously regenerating trap (CRT) compensation module configured to generate a variable CRT threshold. The CRT compensation module selectively outputs a CRT compensation value that modifies the soot model based on comparison between the NOx flow rate and the soot mass-based variable CRT threshold.

Enhanced CRT enablement based on soot mass stored in particulate filter

A system and method for adapting the clean filter correction map for a selective catalyst reduction filter SCRF of an exhaust gas aftertreatment system are provided. The system may be in fluid communication with an engine of a vehicle. The system may include a first pressure sensor and a second pressure. A differential pressure module is in communication with the first pressure sensor and the second pressure sensor and configured to generate a delta pressure signal corresponding to a pressure drop between the first pressure sensor and the second pressure sensor. The system may also include a controller configured to determine a number of completed regeneration events of the SCRF; compare the number of completed regeneration events to an evaluation element; and enable an adaptation module by executing one of a first control action, a second control action, and a third control action.

Method and system for adapting a clean filter correction map for a selective catalyst reduction filter

A method of correcting a soot mass estimate in a vehicle exhaust after-treatment device includes monitoring an exhaust gas pressure drop across a particulate filter included with the vehicle exhaust after-treatment device; determining an initial soot mass estimate from a monitored exhaust gas pressure drop; revising the initial soot mass estimate in view of a monitored engine speed, engine load, exhaust gas temperature, and NOx gas flow rate; and generating a particulate filter regeneration request if the revised soot mass estimate exceeds a threshold.

NOx-flowrate and temperature correction during soot mass estimation in a vehicle exhaust after-treatment device

An exhaust treatment system includes a selective catalyst reduction filter (SCRF) device, a reductant delivery system, and a reductant storage module. The SCRF device includes a filter portion having a washcoat disposed thereon that defines a washcoat thickness (WCT). The reductant delivery system is configured to inject a reductant that reacts with the washcoat. The reductant storage module is in electrical communication with the reductant delivery system to determine a reductant setpoint that controls the amount of reductant injected from the reductant delivery system. The exhaust treatment system further includes a WCT compensation module configured to electrically communicate a WCT compensation value to the reductant storage module. The reductant storage module adjusts the setpoint according to the WCT compensation value such that the amount of ammonia that slips from the SCRF device is reduced as compared to the first setpoint.

Selective catalyst reduction filter washcoat thickness ammonia compensation system

A method of correcting a soot mass estimate in a vehicle exhaust aftertreatment device includes monitoring an exhaust gas pressure drop across a particulate filter included with the vehicle exhaust aftertreatment device. Following the detection of a pressure drop, a controller may determine a soot mass estimate from the monitored pressure drop; determine an ash volume estimate representative of an amount of ash within the particulate filter; determine an ash correction factor from the soot mass estimate and the ash volume estimate; and calculate a corrected soot mass value by multiplying the ash correction factor with the soot mass estimate. If the corrected soot mass value exceeds a threshold, the controller may generate a corresponding particulate filter regeneration request.

Accumulated ash correction during soot mass estimation in a vehicle exhaust aftertreatment device

In one exemplary embodiment of the invention, a method for controlling regeneration for an exhaust system of an internal combustion engine, wherein the exhaust system includes a particulate filter is provided, where the method includes determining a mass flow rate of oxygen received from the internal combustion engine, determining a particulate mass within the particulate filter, determining a desired particulate burn rate based on the mass flow rate of oxygen and the particulate mass and determining a current particulate burn rate. The method also includes determining a correction value based on the desired particulate burn rate and the current particulate burn rate, determining a temperature set point for exhaust gas entering the particulate filter based on the correction value, an engine speed and an engine load and communicating a signal, from a controller, to control a parameter for a regeneration system based on the determined temperature set point.

System and method for particulate filter regeneration

An internal combustion engine includes an intake air compressor system and is fluidly coupled to an exhaust aftertreatment system having a particulate filter. A method for operating the internal combustion engine includes determining a total engine-out soot generation based upon a summation of a steady-state engine-out soot generation rate and an engine-out soot generation rate correction. The engine-out soot generation rate correction is either zero when the intake air compressor system is closed-loop controlled or a rate based upon a deviation between an actual boost pressure and an expected boost pressure from the intake air compressor system. The particulate filter is regenerated when the total engine-out soot generation exceeds a predetermined threshold.

A vehicle and method of updating aging of a selective catalytic reduction filter (SCRF) of an exhaust treatment system of the vehicle are disclosed. The method includes determining a desorption rate estimate of a catalyst of the SCRF and determining an ash volume estimate representative of an amount of ash collected inside the SCRF. The method also includes determining an ash correction factor from the ash volume estimate and calculating, via a controller, a corrected desorption rate value by multiplying the ash correction factor with the desorption rate estimate to update the aging of the SCRF.

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Lapeer, MI, United States of America

Christopher C Swoish