Drive train slip for vibration mitigation during skip fire operation

摘要

A variety of methods and devices for mitigating power train vibration during skip fire operation of an engine are described. In one aspect, the slip of a drive train component (such as a torque converter clutch) is based at least in part upon a skip fire characteristic (such as firing fraction, selected firing sequence/pattern, etc.) during skip fire operation of an engine. The modulation of the drive train component slip can also be varied as a function of one or more engine operating parameters such as engine speed and/or a parameter indicative of the output of fired cylinders (such as mass air charge).

主权项

1. A method of mitigating power train vibration during skip fire operation of an engine, the method comprising:
operating an engine in a skip fire operational mode; and for each firing opportunity in a sequence of firing opportunities that occur during the skip fire operation of the engine, determining a drive train component slip dynamically on an individual firing opportunity by firing opportunity basis, wherein the slip of the drive train component associated with each firing opportunity is based at least in part upon a skip/fire decision associated with such firing opportunity; and modulating the slip of the drive train component in accordance with the determined drive train component slip, whereby in at least some circumstances, the slip of the drive train will be adjusted both up and down for different firing opportunities within a single engine cycle while operating in the skip fire mode.