| 摘要 |
<p>A method and a system are presented for determining and utilizing pressure in an exhaust gas pipe connected to a combustion engine. A first gas sensor is configured to provide a first measurement value y1 corresponding to a first concentration of a substance, where said first gas sensor is pressure dependent and arranged in a first position upstream of an aftertreatment device in said exhaust gas pipe. A second gas sensor is configured to provide a second measurement value y2 corresponding to a second concentration of said substance, where said second gas sensor is arranged in a second position downstream of said aftertreatment device. According to the present invention estimation is performed of at least two characteristic properties including a first pressure sensitivityα1 for said first gas sensor and a first flow dependence for a first pressure P1 at said first position. Based on at least said first pressure sensitivityα1, said first flow dependence and said first y1 and second y2 measurement values, said first pressure P1 is determined, which is then utilized.</p> |
