Method for controlling the fuel supply in a cylinder of a four-stroke internal combustion engine with controlled ignition

摘要

Method for controlling the fuel supply in a cylinder of a four-stroke internal combustion engine with controlled ignition; the control method comprises the steps of: determining, prior to the exhaust phase, a first forecast (PPR-1) of the suction pressure during the suction phase; determining, prior to the exhaust phase, an initial programming of injection of fuel as a function of the desired air/fuel ratio λDES and the first forecast (PPR-1) of the suction pressure during the suction phase; determining at the end of the exhaust phase, a second forecast (PPR-2) of the suction pressure during the suction phase; and determining, at the end of the exhaust phase, a final programming of the fuel injection as a function of the desired air/fuel ratio λDES, of the second forecast (PPR-2) of the suction pressure during the suction phase and of the initial programming of the fuel injection.

主权项

1. Method for controlling the fuel injection in an four-stroke internal combustion engine (1) with controlled ignition comprising at least one cylinder (2), an intake manifold (5) that feeds fresh air into the cylinder (2) and an injector (10) that injects indirectly fuel into the cylinder (2); the control method comprises the steps of:
determining a desired air/fuel ratio (λDES); determining, before the exhaust phase, a first forecast (PPR-1) of the intake manifold suction pressure during the suction phase by means of a first forecast algorithm that uses previous measures (PM) of the intake manifold suction pressure; determining, before the exhaust phase, an initial programming of fuel injection as a function of the desired air/fuel ratio(λDES) and of the first forecast (PPR-1) of the intake manifold suction pressure during the suction phase; controlling, until the end of the exhaust phase, the fuel injection by piloting the injector (10) according to the initial programming of fuel injection, determining a measure (PM-S) of the intake manifold suction pressure at the end of the exhaust phase; determining, at the end of exhaust phase, a second forecast (PPR-2) of the intake manifold suction pressure during the suction phase by means of a second forecast algorithm that also uses the measure (PM-S) of the intake manifold suction pressure at the end of the exhaust phase; determining, at the end of the exhaust phase, a final programming of fuel injection as a function of the desired air/fuel ratio (λDES), of the second forecast (PPR-2) of the intake manifold suction pressure during the suction phase and of the initial programming of fuel injection; and controlling, starting from the suction phase, the fuel injection by piloting the injector (10) according to the final programming of fuel injection.