High load si-hcci transitiion by selective combustion mode switching
AssigneeGM Global Technology Operations LLC
InventorsNicole Wermuth, Paul M. Najt, Hanho Yun
Life of this patent
Estimating the term…
Abstract
A method for operating a direct-injection internal combustion engine includes unevenly distributing load among a plurality of cylinders by operating a portion of the plurality of cylinders in a spark ignition mode and the remaining portion of the plurality of cylinders in a homogeneous charge compression ignition mode.
Claims19
Method for operating a direct-injection internal combustion engine having a plurality of cylinders each individually selectively operable in a homogeneous charge compression ignition mode and a spark ignition mode, the method comprising:
- monitoring a speed of the engine;
- monitoring a load of the engine;
- determining an average load per cylinder based upon the load of the engine;
- determining if engine operation based upon the engine speed and the average load per cylinder is within an operational gap between the homogeneous charge compression ignition mode and the spark ignition mode wherein both combustion modes fail threshold comparisons;
- and
- unevenly distributing load among the plurality of cylinders by operating a portion of the plurality of cylinders in the spark ignition mode and the remaining portion of the plurality of cylinders in the homogeneous charge compression ignition mode.
Method for operating a direct-injection internal combustion engine having a plurality of cylinders each individually selectively operable in a homogeneous charge compression ignition mode and a spark ignition mode, the method comprising:
- estimating a future speed of the engine;
- estimating a future load of the engine;
- assuming even distribution of the future load among the plurality of cylinders, comparing the future speed of the engine and the future load of the engine to a spark ignition operating range to determine a resultant combustion stability;
- assuming even distribution of the future load among the plurality of cylinders, comparing the future speed of the engine and the future load of the engine to a homogeneous charge compression ignition operating range to determine a resultant ringing;
- and
- when the resultant combustion stability and the resultant ringing are determined to be unacceptable, operating a portion of the plurality of cylinders in the spark ignition mode and the remaining portion of the plurality of cylinders in the homogeneous charge compression ignition mode to unevenly distribute load of the engine among the cylinders.
System for operating a direct-injection internal combustion engine having a plurality of cylinders each individually selectively operable in a homogeneous charge compression ignition mode and a spark ignition mode, the system comprising:
- the engine;
- and
- a control module:
- estimating a future state of the engine including a future speed of the engine and a future load of the engine;
- determining an average load per cylinder based upon the future load of the engine;
- determining if the future state the engine is within an unacceptable operating region of engine speed and load whereat spark ignition mode operation produces a predetermined unacceptable level of combustion stability and homogeneous charge compression ignition mode operation produces a predetermined unacceptable level of engine ringing;
- and
- when the future state the engine is within the unacceptable operating region of engine speed and load, controlling individual cylinders in the homogeneous charge compression ignition mode and controlling individual cylinders in the spark ignition mode to unevenly distribute load among the cylinders.
Dependencies are inferred from the claim text.