Device and method for determining the state of aging of an exhaust-gas catalytic converter
View Patent ↗Device and method for determining the state of ageing of an exhaust-gas catalytic converter wherein an oxygen sensor having an oxygen-sensitive region and a temperature-sensitive region can be actuated in such a manner that a temperature measurement and, as an alternative, an oxygen partial pressure measurement can be carried out. There is provision for an electrical conductivity of a conductor structure of the oxygen sensor to be determined and for an exhaust-gas temperature to be determined therefrom. From the sensor measurements, the extent of exhaust gas catalytic converter ageing may be assessed.
1. An apparatus for monitoring the performance of an exhaust-gas catalytic converter arranged in an exhaust pipe of an internal combustion engine, comprising:
an oxygen sensor disposed in the exhaust pipe, the oxygen sensor having an oxygen-sensitive region for detecting an oxygen partial pressure in the exhaust gas and a temperature-sensitive region for detecting a temperature of the exhaust gas; and
a control unit adapted to receive signals from the oxygen sensor corresponding to a detected oxygen partial pressure and a detected exhaust gas temperature,
wherein the control unit has at least two modes, including a first operating mode for operating the oxygen sensor as a temperature sensor which determines the exhaust gas temperature and a second operating mode for determining the oxygen partial pressure of the exhaust gas.
2. The apparatus of claim 1 wherein the control unit determines the exhaust gas temperature in the first operating mode by at least one of determining the electrical conductivity of a solid electrolyte region of the oxygen sensor and determining the electrical conductivity of a heating structure of the oxygen sensor.
3. The apparatus of claim 1 wherein the control unit determines the light-off temperature of the catalytic converter based on the exhaust gas temperature determined in the first operating mode.
4. The apparatus of claim 2 wherein the control unit determines the light-off temperature of the catalytic converter based on the exhaust gas temperature determined in the first operating mode.
5. The apparatus of claim 1 wherein the control unit determines the oxygen storage capacity of the catalytic converter based on the oxygen partial pressure of the exhaust gas determined in the second operating mode.
6. The apparatus of claim 2 wherein the control unit determines the oxygen storage capacity of the catalytic converter based on the oxygen partial pressure of the exhaust gas determined in the second operating mode.
7. The apparatus of claim 3 wherein the control unit determines the oxygen storage capacity of the catalytic converter based on the oxygen partial pressure of the exhaust gas determined in the second operating mode.
8. The apparatus of claim 4 wherein the control unit determines the oxygen storage capacity of the catalytic converter based on the oxygen partial pressure of the exhaust gas determined in the second operating mode.
9. The apparatus of claim 1 further comprising:
a temperature probe provided in the exhaust pipe,
wherein at least a partial region of the catalytic converter is located between the oxygen sensor and the temperature probe.
10. The apparatus of claim 2 further comprising:
a temperature probe provided in the exhaust pipe,
wherein at least a partial region of the catalytic converter is located between the oxygen sensor and the temperature probe.
11. The apparatus of claim 3 further comprising:
a temperature probe provided in the exhaust pipe,
wherein at least a partial region of the catalytic converter is located between the oxygen sensor and the temperature probe.
12. The apparatus of claim 4 further comprising:
a temperature probe provided in the exhaust pipe,
wherein at least a partial region of the catalytic converter is located between the oxygen sensor and the temperature probe.
13. The apparatus of claim 5 further comprising:
a temperature probe provided in the exhaust pipe,
wherein at least a partial region of the catalytic converter is located between the oxygen sensor and the temperature probe.
14. The apparatus of claim 6 further comprising:
a temperature probe provided in the exhaust pipe,
wherein at least a partial region of the catalytic converter is located between the oxygen sensor and the temperature probe.
15. The apparatus of claim 7 further comprising:
a temperature probe provided in the exhaust pipe,
wherein at least a partial region of the catalytic converter is located between the oxygen sensor and the temperature probe.
16. The apparatus of claim 8 further comprising:
a temperature probe provided in the exhaust pipe,
wherein at least a partial region of the catalytic converter is located between the oxygen sensor and the temperature probe.
17. The apparatus of claim 1 further comprising:
a second oxygen sensor disposed in the exhaust pipe upstream of the catalytic converter,
wherein the first oxygen sensor is disposed in one of the catalytic converter and the exhaust gas pipe downstream of the catalytic converter.
18. The apparatus of claim 2 further comprising:
a second oxygen sensor disposed in the exhaust pipe upstream of the catalytic converter,
wherein the first oxygen sensor is disposed in one of the catalytic converter and the exhaust gas pipe downstream of the catalytic converter.
19. The apparatus of claim 3 further comprising:
a second oxygen sensor disposed in the exhaust pipe upstream of the catalytic converter,
wherein the first oxygen sensor is disposed in one of the catalytic converter and the exhaust gas pipe downstream of the catalytic converter.
20. The apparatus of claim 4 further comprising:
a second oxygen sensor disposed in the exhaust pipe upstream of the catalytic converter,
wherein the first oxygen sensor is disposed in one of the catalytic converter and the exhaust gas pipe downstream of the catalytic converter.
21. The apparatus of claim 5 further comprising:
a second oxygen sensor disposed in the exhaust pipe upstream of the catalytic converter,
wherein the first oxygen sensor is disposed in one of the catalytic converter and the exhaust gas pipe downstream of the catalytic converter.
22. The apparatus of claim 6 further comprising:
a second oxygen sensor disposed in the exhaust pipe upstream of the catalytic converter,
wherein the first oxygen sensor is disposed in one of the catalytic converter and the exhaust gas pipe downstream of the catalytic converter.
23. The apparatus of claim 7 further comprising:
a second oxygen sensor disposed in the exhaust pipe upstream of the catalytic converter,
wherein the first oxygen sensor is disposed in one of the catalytic converter and the exhaust gas pipe downstream of the catalytic converter.
24. The apparatus of claim 8 further comprising:
a second oxygen sensor disposed in the exhaust pipe upstream of the catalytic converter,
wherein the first oxygen sensor is disposed in one of the catalytic converter and the exhaust gas pipe downstream of the catalytic converter.
25. The apparatus of claim 9 further comprising:
a second oxygen sensor disposed in the exhaust pipe upstream of the catalytic converter,
wherein the first oxygen sensor is disposed in one of the catalytic converter and the exhaust gas pipe downstream of the catalytic converter.
26. The apparatus of claim 10 further comprising:
a second oxygen sensor disposed in the exhaust pipe upstream of the catalytic converter,
wherein the first oxygen sensor is disposed in one of the catalytic converter and the exhaust gas pipe downstream of the catalytic converter.
27. The apparatus of claim 11 further comprising:
a second oxygen sensor disposed in the exhaust pipe upstream of the catalytic converter,
wherein the first oxygen sensor is disposed in one of the catalytic converter and the exhaust gas pipe downstream of the catalytic converter.
28. The apparatus of claim 12 further comprising:
a second oxygen sensor disposed in the exhaust pipe upstream of the catalytic converter,
wherein the first oxygen sensor is disposed in one of the catalytic converter and the exhaust gas pipe downstream of the catalytic converter.
29. The apparatus of claim 13 further comprising:
a second oxygen sensor disposed in the exhaust pipe upstream of the catalytic converter,
wherein the first oxygen sensor is disposed in one of the catalytic converter and the exhaust gas pipe downstream of the catalytic converter.
30. The apparatus of claim 14 further comprising:
a second oxygen sensor disposed in the exhaust pipe upstream of the catalytic converter,
wherein the first oxygen sensor is disposed in one of the catalytic converter and the exhaust gas pipe downstream of the catalytic converter.
31. The apparatus of claim 15 further comprising:
a second oxygen sensor disposed in the exhaust pipe upstream of the catalytic converter,
wherein the first oxygen sensor is disposed in one of the catalytic converter and the exhaust gas pipe downstream of the catalytic converter.
32. The apparatus of claim 16 further comprising:
a second oxygen sensor disposed in the exhaust pipe upstream of the catalytic converter,
wherein the first oxygen sensor is disposed in one of the catalytic converter and the exhaust gas pipe downstream of the catalytic converter.