REDUCING FIRING DECISION LATENCY IN SKIP FIRE ENGINE OPERATION

摘要

Techniques and controllers are described for dynamically determining when to request firing decisions for individual firing opportunities while operating an internal combustion engine in a skip fire mode. In one aspect, a skip fire controller is arranged to periodically determine the timing by which a next cylinder firing decision request must be made in order to assure that a corresponding firing decision can be implemented as desired, and whether there is sufficient time to wait until at least the next periodic timing determination is made to request the next cylinder firing decision. When there is not sufficient time to wait, a firing decision request is made and the corresponding working cycle is either skipped or fired based on the received firing decision. When there is sufficient time to wait, the firing decision request is delayed until at least the next periodic timing determination is made.

主权项

1. A method of dynamically determining when to request firing decisions for individual firing opportunities while operating an internal combustion engine in a skip fire mode, the method comprising establishing a sequence of timing checks, wherein each timing check includes:
determining a timing by which a next cylinder firing decision request must be made in order to assure that a corresponding firing decision can be implemented as desired; making a firing decision request when it is determined that there is not sufficient time to wait until at least the next timing check to request the next cylinder firing decision; and delaying the firing decision request when it is determined that there is sufficient time to wait until at least the next timing check is made to request the next cylinder firing decision.