Controller and method for controlling operation of an aftertreatment system based on short-term and long-term cumulative degradation estimates

Patent metadata

Field	Value
Publication number	US-11635011-B2
Application number	US-202217941337-A
Country	US
Kind code	B2
Filing date	Sep 9, 2022
Priority date	Mar 12, 2020
Publication date	Apr 25, 2023
Grant date	Apr 25, 2023

Abstract

A controller for controlling operation of an aftertreatment system that is configured to treat constituents of an exhaust gas produced by an engine, the aftertreatment system including a selective catalytic reduction (SCR) catalyst, the controller configured to: generate a short-term cumulative degradation estimate of the SCR catalyst corresponding to reversible degradation of the SCR catalyst due to sulfur and/or hydrocarbons based on a SCR catalyst temperature parameter; generate a long-term cumulative degradation estimate of the SCR catalyst corresponding to thermal aging of the SCR catalyst based on the SCR catalyst temperature parameter; generate a combined degradation estimate of the SCR catalyst based on the short-term cumulative degradation estimate and the long-term cumulative degradation estimate; and adjust an amount of reductant and/or an amount of hydrocarbons inserted into the aftertreatment system based on the combined degradation estimate of the SCR catalyst.

First claim

What is claimed is:

1. A controller for controlling operation of an aftertreatment system configured to treat constituents of an exhaust gas produced by an engine, the aftertreatment system including a selective catalytic reduction (SCR) catalyst, the controller configured to:
generate a short-term cumulative degradation estimate of the SCR catalyst corresponding to reversible degradation of the SCR catalyst due to sulfur and/or hydrocarbons based on a SCR catalyst temperature parameter;
generate a long-term cumulative degradation estimate of the SCR catalyst corresponding to thermal aging of the SCR catalyst based on the SCR catalyst temperature parameter;
generate a combined degradation estimate of the SCR catalyst based on the short-term cumulative degradation estimate and the long-term cumulative degradation estimate; and
adjust an amount of reductant and/or an amount of hydrocarbons inserted into the aftertreatment system based on the combined degradation estimate.

2. The controller of claim 1 , wherein:
the SCR catalyst temperature parameter comprises an inlet exhaust gas temperature at an inlet of the SCR catalyst, an outlet exhaust gas temperature at an outlet of the SCR catalyst, or a SCR catalyst temperature of the SCR catalyst.

3. The controller of claim 2 , wherein the SCR catalyst temperature parameter is determined using a physical temperature sensor.

4. The controller of claim 2 , wherein the SCR catalyst temperature is calculated based on operating parameters of the exhaust gas.

5. The controller of claim 1 , further configured to:
modify stored ammonia slip data corresponding to ammonia slip through the SCR catalyst relative to a SCR catalyst temperature based on at least the combined degradation estimate, and
adjust the amount of reductant and/or the amount of hydrocarbons inserted into the aftertreatment system based on the modified stored ammonia slip data.

6. The controller of claim 1 , further configured to:
modify stored hydrocarbon slip data corresponding to hydrocarbon slip through the DOC catalyst relative to a DOC catalyst temperature based on at least the combined degradation estimate, and
adjust the amount of hydrocarbons inserted into the aftertreatment system based on the modified stored hydrocarbon slip data.

7. The controller of claim 6 , wherein the controller is further configured to:
modify the stored ammonia slip data in response to:
a target value of a SCR catalyst temperature of the SCR catalyst or an ammonia to NO x ratio,
an exhaust flow rate,
a SCR catalyst inlet temperature at an inlet of the SCR catalyst, and
an exhaust gas composition of the exhaust gas.

8. The controller of claim 1 , further configured to:
receive a population SCR catalyst damage signal corresponding to an amount of SCR catalyst damage experienced by a plurality of vehicle SCR catalysts included in a respective plurality of vehicle aftertreatment systems, each of the plurality of vehicle aftertreatment systems being substantially similar to the aftertreatment system, and
modify the short-term cumulative degradation estimate and the long-term cumulative degradation estimate based on the signal.

9. The controller of claim 8 , wherein the population SCR catalyst damage signal is received by the controller via a cloud network or a remote server.

10. The controller of claim 1 , wherein the controller is operably coupled to a telematics system.

11. The controller of claim 10 , further configured to:
determine an aging value of the SCR catalyst based on the combined degradation estimate of the SCR catalyst, and transmit the aging value of the SCR catalyst to the telematics system for setting a preventive maintenance alert.

12. A method for a controller for controlling operation of an aftertreatment system configured to treat constituents of an exhaust gas produced by an engine, the aftertreatment system including a selective catalytic reduction (SCR) SCR catalyst or a diesel oxidation catalyst, the method comprising:
generating a short-term cumulative degradation estimate of the SCR catalyst corresponding to reversible degradation of the SCR catalyst due to sulfur and/or hydrocarbons based on a SCR catalyst temperature parameter;
generating a long-term cumulative degradation estimate of the SCR catalyst corresponding to thermal aging of the SCR catalyst based on the SCR catalyst temperature parameter,
generating a combined degradation estimate of the SCR catalyst based on the short-term cumulative degradation estimate and the long-term cumulative degradation estimate; and
adjusting an amount of reductant and/or an amount of hydrocarbons inserted into the aftertreatment system based on the combined degradation estimate.

13. The method of claim 12 , wherein:
the SCR catalyst temperature parameter comprises an inlet exhaust gas temperature at an inlet of the SCR catalyst, an outlet exhaust gas temperature at an outlet of the SCR catalyst, or a SCR catalyst temperature of the SCR catalyst.

14. The method of claim 13 , wherein the SCR catalyst temperature parameter is determined using a physical temperature sensor.

15. The method of claim 13 , wherein the SCR catalyst temperature parameter is calculated based on operating parameters of the exhaust gas.

16. The method of claim 12 , comprising:
modifying stored ammonia slip data corresponding to ammonia slip through the SCR catalyst relative to a SCR catalyst temperature based on at least the combined degradation estimate, and
adjusting the amount of reductant and/or the amount of hydrocarbons inserted into the aftertreatment system based on the modified stored ammonia slip data.

17. The method of claim 12 , further comprising:
modifying stored hydrocarbon slip data corresponding to hydrocarbon slip through the DOC catalyst relative to a DOC catalyst temperature based on at least the combined degradation estimate, and
adjusting the amount of reductant and/or the amount of hydrocarbons inserted into the aftertreatment system based on the modified stored hydrocarbon slip data.

18. The method of claim 16 , comprising:
modifying the stored ammonia slip data in response to:
a target value of a SCR catalyst temperature of the SCR catalyst or an ammonia to NO x ratio,
an exhaust flow rate,
a SCR catalyst inlet temperature at an inlet of the SCR catalyst, and
an exhaust gas composition of the exhaust gas.

19. The method of claim 12 , comprising:
receiving a population SCR catalyst damage signal corresponding to an amount of SCR catalyst damage experienced by a plurality of vehicle SCR catalysts included in a respective plurality of vehicle aftertreatment systems, each of the plurality of vehicle aftertreatment systems being substantially similar to the aftertreatment system, and
modifying the short-term cumulative degradation estimate and the long-term cumulative degradation estimate based on the signal.

20. The method of claim 19 , comprising:
receiving the population SCR catalyst damage signal by the controller via a cloud network or a remote server.

21. The method of claim 12 , wherein the controller is operably coupled to a telematics system.

22. The method of claim 12 , further comprising:
determining an aging value of the SCR catalyst based on the combined degradation estimate of the SCR catalyst, and
transmitting the aging value of the SCR catalyst to the telematics system for setting a preventive maintenance alert.

Assignees

• Cummins Emission Solutions Inc

Inventors

• Clerc James C
• Jones Bradley V
• Greca Marc Alexander
• Ratan Santosh Kumar
• Daya Rohil
• Dadi Karthik Venkata Rama Krishna
• Gong Jinqian
• Staebler Bryon D
• Corbet Todd A
• Tschimwang Alain Ngoy
• Sasidharan Premjee
• Hall David C

Classifications

• F01N2900/0412

  using pre-calibrated maps, tables or charts · CPC title

• F01N2900/1404

  Exhaust gas temperature · CPC title

• F01N3/208 Primary

  Control of selective catalytic reduction [SCR], e.g. by adjusting the dosing of reducing agent · CPC title

• F01N2550/02

  Catalytic activity of catalytic converters · CPC title

• F01N2610/03

  the substance being hydrocarbons, e.g. engine fuel · CPC title