Delphi Technologies, Inc.

Martin M&uuml;ller

Jeffrey M Pfeiffer

Gary Arthur Nichols

Daniel Lee McKay

Edward George Himes

A cam phase control method for an internal combustion engine schedules cam phase to optimize emissions and fuel economy, but bounds the scheduled cam phase for continuous achievement of the desired inlet airflow. The volumetric efficiency required to achieve the desired inlet airflow at a specified intake manifold vacuum is compared to the maximum achievable volumetric efficiency at the specified vacuum. When the required volumetric efficiency is less than the maximum value, the cam phase is controlled according to the lesser of the scheduled cam phase and the highest cam phase for achieving the required volumetric efficiency; when the required volumetric efficiency is equal to or greater than the maximum value, the cam phase is controlled to a setting that maximizes the volumetric efficiency.

Method of bounding cam phase adjustment in an internal combustion engine

A method of estimating the concentration of residual exhaust gas in an internal combustion engine having variable cam phase control is based on engine dynamometer and engine simulator data. Since both the volumetric efficiency and the residual exhaust gas concentration of an engine vary monotonically in response to changes in cam phase, the simulated residual concentration data is deemed to be reliable if the simulated volumetric efficiency data matches volumetric efficiency data determined by engine dynamometer testing. Volumetric efficiency test data is compared to simulated volumetric efficiency data, and the simulation software is tuned until the simulated data matches the test data. At such point, the simulated residual concentration data is deemed to be reliable, and is used to calibrate a model relating residual concentration to cam phase angle, and such model is then used by an engine controller to estimate residual exhaust gas concentration during operation of the engine.

Method of estimating residual exhaust gas concentration in a variable cam phase engine

An improved engine torque management control that coordinates engine throttle, spark and EGR under predefined highly throttled conditions so as to maximize the fuel economy improvement of EGR without degrading engine performance. Under the predefined conditions, EGR is increased to a level that maximizes the fuel economy improvement without causing combustion instability, and the throttle position and spark timing are controlled to compensate for the anticipated torque loss while increasing volumetric efficiency and reducing pumping losses. During idle and steady state cruising operation, EGR is increased, and engine throttle position is controlled to regulate the estimated engine output torque in accordance with the driver requested output torque. During transient torque increases, throttle control alone is used to regulate the output torque, while in transient torque decreases, the throttle position is maintained and spark timing is used to regulate the output torque.

Growing community of inventors

Ann Arbor, MI, United States of America

Martin Müller

Growing community of inventors

Ann Arbor, MI, United States of America

Martin M&uuml;ller

Martin Müller