Real-time determination of a fresh-air mass in a cylinder
AssigneeBayerische Motoren Werke Aktiengesellschaft
InventorSebastian Grasreiner
Life of this patent
Estimating the term…
Abstract
Please substitute the new Abstract submitted herewith for the original Abstract: A method for determining a fresh-air-mass parameter in a cylinder of an internal combustion engine in a motor vehicle includes identifying a cylinder which is at the end of an intake stroke or at the beginning of a compression stroke during operation of the motor vehicle, determining a diagnosis time window which lasts for a period of time after closing of the inlet valves of the identified cylinder within a region of low torque of the internal combustion engine, ascertaining a development in the speed of the internal combustion engine during the diagnosis time window, and determining the fresh-air-mass parameter in the identified cylinder.
Claims16
A method for determining a fresh-air mass parameter in a cylinder of an internal combustion engine in a motor vehicle, the method comprising:
- identifying a cylinder which is at an end of an intake stroke or at a beginning of a compression stroke during driving operation of the motor vehicle;
- determining a diagnosis time window which lasts for a period of time after closing inlet valves of the identified cylinder within a low-torque range of the internal combustion engine;
- determining at least two values of a crankshaft speed of the internal combustion engine during the diagnosis time window;
- determining a cylinder load parameter in the identified cylinder in dependence on the determined at least two values of the crankshaft speed;
- determining the fresh-air mass parameter in the identified cylinder in dependence on the determined cylinder load parameter;
- and
- controlling a fuel injection quantity for a subsequent operating cycle of the cylinder or a subsequently firing cylinder based on the fresh-air mass parameter in the identified cylinder.
An engine control unit configured to:
- identify a cylinder which is at an end of an intake stroke or at a beginning of a compression stroke during driving operation of a motor vehicle;
- determine a diagnosis time window which lasts for a period of time after closing inlet valves of the identified cylinder within a low-torque range of an internal combustion engine of the motor vehicle;
- determine at least two values of a crankshaft speed of the internal combustion engine during the diagnosis time window with a real-time-capable sampling quality;
- determine a cylinder load parameter in the identified cylinder in dependence on the determined at least two values of the crankshaft speed;
- determine a fresh-air mass parameter in the identified cylinder in dependence on the determined cylinder load parameter;
- and
- control a fuel injection quantity for a subsequent operating cycle of the cylinder or a subsequently firing cylinder based on values of the fresh-air mass parameter.
Dependencies are inferred from the claim text.