Compensation for gas composition

摘要

An engine control system (81) for inferring the composition of the gaseous fuel to compensate variations in the gas composition comprises an exhaust gas sensor (83) in communication with a flow path of the exhaust gas for measuring NOx emissions and Lambda in the exhaust gas at typically a full load condition. An engine control module (23) receives an indication of NOx emissions and Lambda in the exhaust gas from the exhaust gas sensor and references a suitable function, look-up table, or map to identify gaseous fuel composition from the parameters relating to the NOx emissions and Lambda in the exhaust gas received from the exhaust gas sensor. The measurement of each parameter (NOx emissions and Lambda in the exhaust gas) is then compared with the respective allowable range for that load condition and the timing of ignition of a combustible charge adjusted accordingly to provide compensation.