Air-fuel ratio regulation arrangement

摘要

The arrangement includes an oxygen sensor (30) which provides an output signal representing the concentration of oxygen flowing through an NOx trap (18). An error signal generator provides an air-fuel ratio error signal in response to the current air-fuel ratio signal derived from the oxygen concentration, and a nominal air-fuel ratio. A regulator (26) connected with a fuel injection system adjust a fuel concentration supplied to the combustion engine. The arrangement includes a first oxygen sensor which is connected with an exhaust system (10, 100) of a combustion engine is arranged in such way, that it provides an output signal representing the concentration of the oxygen streaming through an NOx trap (18). A fuel injection system (22, 24) is connected with the combustion engine. A processor responding to the output signal of the oxygen sensor, generates a signal representing the current air-fuel ratio of the exhaust fumes in the trap. An error signal generator provides an error signal for the air-fuel ratio in response to the current air-fuel ratio signal and a nominal air-fuel ratio. A regulator (26) is connected with the fuel injection system and responds to the error signal, to adjust a fuel concentration supplied to the combustion engine.