Adaptive lean limit air fuel control using combustion pressure sensor feedback

摘要

Controlling operation of an internal combustion engine at lean air fuel ratios uses an in-cylinder pressure sensor. The in-cylinder pressure sensor is coupled to each cylinder of the engine and measures in-cylinder pressure and generates an output signal as a function of such pressure. Airflow into the engine is also sensed and both the airflow and in-cylinder pressure are applied to the fuel controller for generating a fuel injection drive signal. Compensation means coupled to the in-cylinder pressure sensor means and airflow indication means modify the fuel air command applied to the engine as a function of airflow and in-cylinder pressure. The compensation means is also coupled to the fuel controller for applying a fuel command signal to the fuel controller thereby permitting engine operation at the lean air fuel ratio limit.