METHOD (VERSIONS) AND SYSTEM FOR ADJUSTMENT OF AIR-FUEL RATIO Russian patent published in 2016 - IPC F01N3/00 F01N11/00 F02D41/30 

FIELD: engines.

SUBSTANCE: invention relates to methods and systems for adjustment of air-fuel ratio of the engine. Method of controlling air-fuel ratio of the engine consists in controlling the frequency and relative duration of the air-fuel ratio, used for control of engine cylinders on the basis of an error between the required relative duration and relative duration of the signal obtained from the oxygen sensor on the basis of an error between the required frequency and frequency of the signal obtained from the oxygen sensor, as well as based on the type of fuel. Sensor is located downstream to the catalyst. Control system of air-fuel ratio engine includes the first oxygen sensor located in the engine exhaust gases emission pipeline. Catalyst is located in the engine exhaust gases emission pipeline. Second oxygen sensor is located in the engine exhaust gases emission pipeline downstream to the catalyst. Controller contains instructions for controlling air-fuel ratio of the engine relative duration and frequency of output signal of the second oxygen sensor based on the required voltage of oxygen pickup arranged downstream to the catalyst.

EFFECT: use of the invention improves operating efficiency of the catalyst.

19 cl, 4 dwg