Dynamic skip fire operation of a gasoline compression ignition engine
AssigneesTula Technology, Inc., Delphi Technologies, Inc.
InventorsSiamak HASHEMI, Matthew A. YOUNKINS, John E. KIRWAN
Life of this patent
Estimating the term…
Abstract
A gasoline compression ignition engine is operated in two modes. In a one mode of operation the engine is operated with a firing fraction of one, corresponding to all of the cylinders being active, working cylinders. In a second skip fire mode of operation a firing fraction of less than one may be used under conditions, such as a low load condition, to improve efficiency. The skip fire mode of operation may also be selected in part based on other considerations, such as maintaining an exhaust temperature conducive for efficient catalytic converter operation or limiting cylinder output variability.
Claims27
A method of operating a gasoline compression ignition engine having a plurality of cylinders, comprising:
- selecting a firing fraction of the gasoline compression ignition engine for a desired engine output;
- and
- operating the gasoline compression engine in a skip fire manner according to the selected firing fraction, wherein the selected firing fraction determines a fraction of cylinders that are active and fired with the remaining cylinders being skipped such that the skipped cylinders are deactivated,
- wherein the firing fraction is at least partially selected to achieve at least a minimum load in active cylinders.
(canceled)
A skip fire engine controller for a gasoline compression ignition engine having a plurality of cylinders, comprising:
- a skip firing fraction module arranged to determine an operational firing fraction and associated engine settings to deliver a desired engine output for the gasoline compression ignition (GCI) engine;
- and
- a firing timing controller arranged to direct firings in a skip fire manner that delivers the selected operational firing fraction,
- wherein the skip fire engine controller is arranged to select the firing fraction to achieve at least a minimum load in active cylinders.
(canceled)
An engine system, comprising:
- a gasoline compression ignition engine;
- and
- a skip fire engine controller arranged to select a firing fraction of the gasoline compression ignition engine to achieve a desired engine output,
- wherein the firing fraction is at least partially selected to achieve at least a minimum load in active cylinders of the gasoline compression engine.
Dependencies are inferred from the claim text.