Fuel injection control system for engine

摘要

A fuel injection control system of an engine includes: (a) an intake air quantity estimation unit for estimating the quantity of intake air; (b) an intake fuel quantity estimation unit for estimating the quantity of intake fuel; (c) an estimated air-fuel ratio calculation unit for calculating an estimated air-fuel ratio; (d) a target air-fuel ratio setting unit for setting a target air-fuel ratio; (e) a feedback control unit for providing a fuel injection signal to the engine, which fuel injection signal is outputted also to the intake fuel quantity estimation unit as one of the predetermined signals; and (f) an actual air-fuel ratio deviation estimation unit for estimating a deviation of an actual air-fuel ratio or a factor correlated thereto from a predetermined level, which unit is programmed to output a deviation signal based on predetermined signals. In the above, at least one unit selected from the intake air quantity estimation unit, the intake fuel estimation unit, and the target air-fuel ratio setting unit is provided with a learning function which is programmed to modify output from the at least one unit based on the deviation signal used as teacher data to minimize the deviation. The system requires a reduced number of sensors.