Method for checking cross-sensitivity of ammonia of nitrogen oxide sensor in SCR catalyst system of diesel engine, involves determining nitrogen oxide concentration in exhaust gas between catalysts from nitrogen oxide model

摘要

The method involves constructing a model of nitrogen oxide concentration in exhaust gas between catalysts (13, 21). An ammonia slip model of the catalyst is constructed. Operability of nitrogen oxide sensors (41, 44, 46) is checked by verifying a sensor signal with ammonia concentration in the exhaust gas between the catalysts that are determined by the ammonia slip model. Nitrogen oxide concentration in the exhaust gas between the catalysts is determined from the nitrogen oxide model. An independent claim is also included for a computer program comprising a set of instructions to perform a method for checking cross-sensitivity of ammonia of a nitrogen oxide sensor in a catalyst system.