| 摘要 |
The invention relates to a method and a device for detecting at least one concentration of a gas component of a gas in a measurement gas chamber, in particular for detecting a non-oxygen gas, preferably a nitrogen oxide, in an exhaust gas of an internal combustion engine. For this purpose, the gas is conducted from the measurement gas chamber into a decomposition chamber via a gas access path, in which decomposition chamber at least one sensor electrode having catalytic properties is located. On the at least one sensor electrode, the gas component is catalytically decomposed into decomposition products, wherein at least one interfering gas component, in particular oxygen, is pumped out of the gas access path from at least one measuring electrode arranged in the gas access path. In a standard method (122, 126), at least one of the decomposition products is pumped out of the decomposition chamber from the sensor electrode to a reference electrode or an additional electrode and a pumping voltage and/or a pumping current between the sensor electrode and the reference electrode or the additional electrode is detected as a first measured value correlated with the concentration of the gas component. According to the invention, at least one comparison method (110) is performed at regular or irregular time intervals in addition to the standard method (122, 126), by means of which comparison method a second measured value correlated with the concentration of the gas component is detected. Finally, the second measured value is related (132) to the first measured value. |
