METHOD AND SYSTEM FOR ADAPTATION OF AN ELECTROCHEMICAL GAS SENSOR

摘要

Method and system for adaptation of an electrochemical gas sensor (4) situated in the exhaust line (3) from a combustion engine. Sets of measured values are recorded at three or more different times during a period when the composition of the engine's exhaust gases is maintained substantially unchanged. Each set of measured values comprises a value which corresponds to the magnitude of the sensor's measurement signal, and a value which corresponds to the temperature of the amount of exhaust gases received in the sensor's measuring chamber. A temperature regulating means of the sensor is controlled in such a way that the temperature of said amount of exhaust gases is different at the time of each recording. The values in said sets of measured values and the relationship between them which is indicated by the general gas law serve as a basis for determining a value for one or more constants which form part of the signal processing algorithm used for converting the sensor's measurement signals to a value which represents the concentration of a specific gas in the exhaust gases. The sensor is adapted by adjustment of the signal processing algorithm according to the value determined for each constant.