초록 ▼

An internal combustion engine includes an exhaust gas recirculation (EGR) mechanism for directing a controlled amount of exhaust gas generated by the engine from the exhaust manifold to an intake manifold of the engine. An electronic engine controller (EEC) controls the EGR by determining a base EGR

An internal combustion engine includes an exhaust gas recirculation (EGR) mechanism for directing a controlled amount of exhaust gas generated by the engine from the exhaust manifold to an intake manifold of the engine. An electronic engine controller (EEC) controls the EGR by determining a base EGR rate as a function of a plurality of engine operating parameters. The base EGR rate is then modified by a multiplier to compensate the EGR rate for the effect of humidity. The multiplier represents the EGR percent change per grain of humidity deviation from a predetermined humidity level. The EEC further controls the borderline spark timing of the engine by determining a base spark timing as a function of a plurality of engine operating parameters at a predetermined humidity level. The spark rate is then modified by a multiplier to compensate the spark timing for the effect of humidity. The multiplier represents the degree of spark change per grains of humidity possible without incurring engine knock.

대표청구항 ▼

[ What is claimed is:] [1.] A method of controlling the rate of exhaust gas recirculation in an internal combustion engine, comprising the steps of:generating a rpm value which is indicative of the rotational speed of the engine;generating an air charge value which is indicative of air charge enteri

[ What is claimed is:] [1.] A method of controlling the rate of exhaust gas recirculation in an internal combustion engine, comprising the steps of:generating a rpm value which is indicative of the rotational speed of the engine;generating an air charge value which is indicative of air charge entering an intake manifold of the engine;generating a humidity value which is indicative of the ambient humidity level;determining a base exhaust gas recirculation value as a function of at least the rpm value and the air charge value;modifying the base exhaust gas recirculation value as a function of the generated humidity value to obtain a modified exhaust gas recirculation value; andregulating the rate of exhaust gas recirculation in response to the modified exhaust gas recirculation value.