초록 ▼

A method of controlling the air-fuel ratio of an internal combustion engine having an exhaust passage including a catalytic converter. The method includes providing a first air-fuel ratio sensor upstream of the catalytic converter, and providing a second air-fuel ratio sensor downstream of the catal

A method of controlling the air-fuel ratio of an internal combustion engine having an exhaust passage including a catalytic converter. The method includes providing a first air-fuel ratio sensor upstream of the catalytic converter, and providing a second air-fuel ratio sensor downstream of the catalytic converter. A control module having an input connected to the first and second air-fuel ratio sensors and an output connected to actuators for controlling the engine is also provided. This establishes a first feedback loop including the first air-fuel ratio sensor and a second feedback loop including the second air-fuel ratio sensor. The method further includes detecting an output value of the second air-fuel ratio indicative of a rich or lean exhaust gas air-fuel ratio. In response to the output value, the system monitors the engine mass airflow, and controls the duration of air-fuel ratio of the engine as a function of the engine mass airflow.

대표청구항 ▼

[ What is claimed is:] [1.]1. A method of controlling the air-fuel ratio of an internal combustion engine having an exhaust passage including a catalytic converter, the method comprising the steps of:providing a first air-fuel ratio sensor for characterizing at least one constituent of an exhaust ga

[ What is claimed is:] [1.]1. A method of controlling the air-fuel ratio of an internal combustion engine having an exhaust passage including a catalytic converter, the method comprising the steps of:providing a first air-fuel ratio sensor for characterizing at least one constituent of an exhaust gas stream from the engine, the first air-fuel ratio sensor being positioned upstream of the catalytic converter;providing a second air-fuel ratio sensor for characterizing at least one constituent of the exhaust gas stream from the engine, the second air-fuel ratio sensor being positioned downstream of the catalytic converter;detecting an output value of the second air-fuel ratio sensor wherein the output value is indicative of a rich or lean exhaust gas air-fuel ratio and, in response;monitoring the engine mass airflow; andmodifying the air-fuel ratio of the engine by setting a proportional gain term of a feedback loop as a function of the output value and the engine speed and load, and reducing the proportional gain term as a function of the engine mass airflow.