Method and device for controlling an internal combustion engine

Patent metadata

Field	Value
Publication number	US-9228464-B2
Application number	US-201213592208-A
Country	US
Kind code	B2
Filing date	Aug 22, 2012
Priority date	Sep 6, 2011
Publication date	Jan 5, 2016
Grant date	Jan 5, 2016

Abstract

Embodiments for heating a catalyst are provided. In one example, a method for controlling an internal combustion engine having an exhaust-gas aftertreatment device during a cold-start phase comprises adjusting a temperature of cooling water to a setpoint operating temperature as a function of a degree of aging of the exhaust-gas aftertreatment device of the internal combustion engine, wherein the temperature of the cooling water is increased more quickly as a present degree of aging of the exhaust-gas aftertreatment device increases.

First claim

The invention claimed is:

1. A method for controlling an internal combustion engine having an exhaust-gas aftertreatment device during a cold-start phase, comprising:
adjusting a temperature of cooling water to a setpoint operating temperature as a function of a degree of aging of the exhaust-gas aftertreatment device of the internal combustion engine, wherein the temperature of the cooling water is increased more quickly as a present degree of aging of the exhaust-gas aftertreatment device increases.

2. The method as claimed in claim 1 , wherein, during the cold-start phase, adjusting the temperature of the cooling water to the setpoint operating temperature as a function of the degree of aging of the exhaust-gas aftertreatment device further comprises one or more of adjusting passive systems including a cooling water circulating pump in the cooling water tract and/or valves in the cooling water circuit, and adjusting active systems including an electric or microwave heater in a cooling water circuit.

3. The method as claimed in claim 1 , wherein the present degree of aging of the exhaust-gas aftertreatment device is determined based on stored tables and/or measured values.

4. The method as claimed in claim 1 , wherein, during the cold-start phase, the temperature of the cooling water is further adjusted to the setpoint operating temperature as a function, which increases continuously with a continuously decreasing gradient, of time.

5. The method as claimed in claim 1 , wherein, during the cold-start phase, the temperature of the cooling water is adjusted to the setpoint operating temperature substantially based on a function including cooling water temperature at time t after starting of the internal combustion engine, cooling water temperature upon starting of the internal combustion engine, setpoint operating temperature of the cooling water, and a constant.

6. The method as claimed in claim 5 , wherein the constant comprises a value for the degree of aging of the exhaust-gas aftertreatment device, said value being of an order of magnitude of at least one hundred seconds for a new exhaust-gas aftertreatment device and becoming progressively smaller with progressive aging of the exhaust-gas aftertreatment device.

7. The method as claimed in claim 1 , wherein the internal combustion engine is installed in a motor vehicle.

8. The method as claimed in claim 1 , wherein the internal combustion engine is a diesel engine.

9. The method as claimed in claim 1 , wherein the exhaust-gas aftertreatment device has a catalytic noble metal coating.

10. A device for controlling the internal combustion engine having the exhaust-gas treatment device during the cold-start phase, the device configured for carrying out the method according to claim 1 .

11. A method for an engine, comprising:
during a cold engine start, adjusting a temperature of coolant in an engine cooling system based on degradation of an exhaust catalyst positioned downstream of the engine.

12. The method of claim 11 , wherein adjusting the temperature of the coolant further comprises adjusting a time constant of a response of the cooling system to reach a setpoint coolant temperature.

13. The method of claim 12 , wherein the time constant decreases as the age of the exhaust catalyst increases.

14. The method of claim 11 , further comprising adjusting one or more of a coolant system pump, valve, and heater to adjust the temperature of the coolant.

15. The method of claim 11 , wherein degradation of the catalyst is determined based on feedback from one or more exhaust sensors positioned downstream of the exhaust catalyst.

16. The method of claim 11 , wherein adjusting the temperature of the coolant further comprises raising coolant temperature more quickly at higher exhaust catalyst degradation levels, and raising coolant temperature more slowly at lower exhaust catalyst degradation levels.

17. An engine system, comprising:
a pump configured to pump coolant to an engine;
a heater positioned along a coolant passageway;
an exhaust catalyst; and
a controller including instructions to, during engine cold start conditions, adjust one or more of the pump and heater responsive to an age of the exhaust catalyst.

18. The engine system of claim 17 , wherein the controller includes instructions to deactivate the pump during engine cold start conditions if the age of the exhaust catalyst is above a first threshold.

19. The engine system of claim 18 , wherein the controller includes instructions to activate the heater during engine cold start conditions if the age of the exhaust catalyst is above a second threshold, larger than the first threshold.

20. The engine system of claim 17 , wherein the controller includes instructions to determine the age of the exhaust catalyst based on feedback from one or more exhaust sensors.

Assignees

• Yacoub Yasser Mohamed Sayed
• Ford Global Tech Llc

Inventors

• Yacoub Yasser Mohamed Sayed

Classifications

• F01N2430/00

  Influencing exhaust purification, e.g. starting of catalytic reaction, filter regeneration, or the like, by controlling engine operating characteristics · CPC title

• F02D41/068

  for warming-up · CPC title

• F01N3/202

  using microwaves · CPC title

• Y02T10/26

  Cross-Sectional Technologies · mapped topic

• F01P7/14

  the coolant being liquid · CPC title