Method and system for a particulate filter having a bypass
AssigneeFord Global Technologies, LLC
InventorsDouglas Raymond Martin, John Eric Rollinger
Life of this patent
Estimating the term…
Abstract
Methods and systems are provided for an emission control device that includes a particulate filter with a bypass. In one example, a method includes bypassing the particulate filter when the exhaust gas has a decreased soot load and when the particulate filter has a decreased soot storage. The method further includes reducing the filter bypass flow and terminating or adjusting a deceleration fuel shut-off operation due to an exhaust temperature proximate to the particulate filter being above a threshold.
Claims20
A method for an engine, comprising:
- via a controller, executing instructions stored in a non-transitory computer storage medium to, responsive to decreased soot generation or decreased soot storage as estimated based on sensors, flowing gasoline combustion exhaust gas to a particulate filter with increased filter bypass flow by controlling an amount of opening of a bypass valve when an exhaust temperature is above a first threshold, wherein the increased filter bypass flow reduces exhaust back pressure and increases a life of the particulate filter;
- and
- responsive to increased soot generation or increased soot storage as estimated based on the sensors, reducing the filter bypass flow and terminating deceleration fuel shut-off operation after a threshold duration by injecting fuel to each cylinder of the engine due to the exhaust temperature being above the first threshold, wherein the reduced filter bypass flow and the terminating the deceleration fuel shut-off operation regenerates the particulate filter.
A method for an engine, comprising:
- via a controller, executing instructions stored in a non-transitory computer storage medium to, responsive to entry conditions for deceleration fuel shut-off (DFSO) operation being met;
- operating the engine in DFSO for a first duration based on an operator-demanded torque, in response to a bypass around a gasoline particulate filter (GPF) disposed in an exhaust passage of the engine being open, wherein the bypass being open reduces exhaust back pressure and increases a life of the GPF;
- and
- operating the engine in DFSO for a second duration based on a temperature of the GPF, in response to the bypass being closed and the temperature being above a first threshold, wherein the bypass being closed and the operating the engine in DFSO for the second duration regenerates the GPF.
A system for an engine, comprising:
- an exhaust passage including a turbocharger turbine and a catalyst;
- a gasoline particulate filter (GPF) disposed in the exhaust passage, downstream of the turbocharger turbine and the catalyst;
- a bypass passage disposed around only the GPF and including a bypass valve disposed therein;
- and
- a controller with computer readable instructions stored in memory for:
- opening the bypass valve in response to a soot level of exhaust gas being less than a first threshold and a soot level stored in the GPF being less than a second threshold and, in response to the bypass valve being open during a deceleration fuel shut-off (DFSO) operation, not limiting a duration of the DFSO operation based on a temperature of the GPF;
- and
- closing the bypass valve in response to one or more of the soot level of the exhaust gas being greater than the first threshold and the soot level stored in the GPF being greater than the second threshold, and, in response to the bypass valve being closed during DFSO operation and the temperature of the GPF being above a first upper threshold, limiting the duration of the DFSO operation based on the temperature of the GPF.
Dependencies are inferred from the claim text.