METHOD AND APPARATUS FOR ADAPTIVE FEEDBACK CONTROL OF AN EXCESS AIR RATIO IN A COMPRESSION IGNITION NATURAL GAS ENGINE

摘要

A computer-implemented method is used to correct deviations between a predicted gas excess air ratio and a calculated excess air ratio in a dual fuel engine or other gas fueled compression ignition engine (10). The method includes determining gas excess air ratio for the engine based at least in part on at least one detected current operating parameter and calculating a predicted exhaust gas oxygen concentration engine based on the predicted gas excess air ratio (Step 124). A time based filtered predicted exhaust gas oxygen concentration value may then be calculated (Step 128) and compared to a time-based filtered measured exhaust gas oxygen concentration value (Step 130). The resultant oxygen concentration deviation value may be used to generate a corrected predicted gas excess air ratio (Step 132).