METHOD FOR OPERATING AN EXHAUST GAS POST TREATMENT SYSTEM OF A DIESEL ENGINE AND EXHAUST GAS POST TREATMENT SYSTEM

摘要

A method for operating an exhaust gas post-treatment system of a diesel engine and associated exhaust gas post-treatment system are described. The system has two NOx sensors upstream and downstream of an SCR catalytic converter. The NOx sensor downstream of the SCR catalytic converter is used to divide the NOx information measured by the sensor upstream of the SCR catalytic converter into an NOx value and an NH₃ value. Using this simple method, the SCR catalyst control and diagnosis can be carried out precisely and robustly.