摘要:
A multi-cylinder spark-ignition direct-injection internal combustion engine is re-fired subsequent to a fuel cutoff event wherein fuel to all cylinders is cutoff. Re-firing the engine includes selectively firing individual cylinders during re-firing engine cycles exclusively at a predetermined fixed fuel mass until all cylinders have been fired at least once, whereafter subsequent firing of individual cylinders is not limited to the predetermined fixed fuel mass.
摘要:
A direct injection spark ignition multi-cylinder internal combustion engine operative in a controlled auto-ignition combustion mode includes a direct fuel injection system, a spark ignition system and a controllable engine valve system. The air/fuel ratio in the exhaust gas feedstream and an intake mass air flow are measured and an actual air/fuel ratio is calculated based upon the intake mass air flow and engine fueling. Magnitude of a negative valve overlap period between an exhaust valve closing and an intake valve opening is adjusted based upon the measured mass air flow. Timing of pre-injection fueling is adjusted during the negative valve overlap period based upon the measured air/fuel ratio.
摘要:
An internal combustion engine is selectively operative in a spark ignition combustion mode and a controlled auto-ignition combustion mode. An EGR valve operative to control flow of exhaust gas to an intake manifold is monitored, including commanding the EGR valve to a closed position and monitoring operation of the internal combustion engine. An intake manifold pressure due to a fresh air charge is estimated based upon the operation of the engine. The intake manifold pressure is measured, and the estimated intake manifold pressure is compared to the measured intake manifold pressure.
摘要:
A method for selecting a preferred combustion mode for an internal combustion engine operative in a plurality of combustion modes is described. The method includes selecting a combustion mode in terms of first and second engine parameters, and separating the engine operating region into zones defined by the first parameter. Each of the zones is further separated into sub-zones defined by the second parameter. A combustion mode is associated with each of the sub-zones. Operating states are determined for the first and second parameters. One of the zones is identified based upon the state for the first parameter. One of the sub-zones of the identified zone is identified based upon the state for the second parameter, along with a combustion mode associated with the identified sub-zone. The engine is controlled to the preferred combustion mode, depending upon hysteresis.
摘要:
A direct injection spark ignition multi-cylinder internal combustion engine operative in a controlled auto-ignition combustion mode includes a direct fuel injection system, a spark ignition system and a controllable engine valve system. The air/fuel ratio in the exhaust gas feedstream and an intake mass air flow are measured and an actual air/fuel ratio is calculated based upon the intake mass air flow and engine fueling. Magnitude of a negative valve overlap period between an exhaust valve closing and an intake valve opening is adjusted based upon the measured mass air flow. Timing of pre-injection fueling is adjusted during the negative valve overlap period based upon the measured air/fuel ratio.
摘要:
A model-based estimation of mass airflow is provided which provides an accurate estimation of mass airflow without introducing undesirable time delays characteristic of filtered mass airflow signals.
摘要:
A method for selecting a preferred combustion mode for an internal combustion engine operative in a plurality of combustion modes is described. The method includes selecting a combustion mode in terms of first and second engine parameters, and separating the engine operating region into zones defined by the first parameter. Each of the zones is further separated into sub-zones defined by the second parameter. A combustion mode is associated with each of the sub-zones. Operating states are determined for the first and second parameters. One of the zones is identified based upon the state for the first parameter. One of the sub-zones of the identified zone is identified based upon the state for the second parameter, along with a combustion mode associated with the identified sub-zone. The engine is controlled to the preferred combustion mode, depending upon hysteresis.
摘要:
A method for controlling combustion in a multi-cylinder internal combustion engine operating in a controlled auto-ignition mode includes providing combustion control parameters, determining peak cylinder pressures and crank angle location of the peak cylinder pressures. Cylinder volumes at the peak cylinder pressures and at intake valve closings are determined and cylinder pressures at intake valve closings are determined. A combustion parameter for each cylinder is calculated based upon the peak cylinder pressure, the cylinder pressure at the intake valve closing, the crank angle location of the peak cylinder pressure, the cylinder volume coincident with the peak cylinder pressure, and the cylinder volume at the intake valve closing. A target combustion parameter is determined and the calculated combustion parameter for each cylinder is compared to the target combustion parameter. The provided combustion control parameters for each cylinder are adjusted to balance the combustion parameter across all cylinders based on the comparison. The engine is controlled based on the adjusted provided combustion control parameters.
摘要:
A method for controlling a multi-cylinder direct-injection internal combustion engine includes establishing an external exhaust gas recirculation valve from a present position to a target position to achieve a target exhaust gas recirculation, and synchronizing combustion initiation timing with actual exhaust gas recirculation as actual exhaust gas recirculation changes from a first exhaust gas recirculation value corresponding to the present position of the external exhaust gas recirculation valve to a second exhaust gas recirculation value corresponding to the target position of the external exhaust gas recirculation valve.
摘要:
A method for controlling combustion in a multi-cylinder spark-ignition direct-injection internal combustion engine includes determining a desired combustion phasing for maintaining acceptable combustion properties, monitoring combustion phasing of each cylinder, selecting a target combustion phasing corresponding to one of the cylinders having a most retarded combustion phasing, adjusting spark timing in each cylinder not having the most retarded combustion phasing to achieve the target combustion phasing to balance the combustion phasing in all the cylinders at the target combustion phasing, and adjusting an external EGR percentage to converge the balanced combustion phasing in all the cylinders toward the desired combustion phasing.