Closed loop minimum timing for the best torque (MBT) timing control in i.c. engines using ionization feedback

摘要

The present invention relates to engine ignition systems. More particularly, it relates to a method of controlling ignition timing. This feature of the present invention comprises a closed loop which uses estimated Minimum timing for the Best Torque (MBT) timing criteria and ignition diagnostics (knock, partial-burn, and misfire) to control engine ignition. When the engine is not knock limited, it operates at its MBT timing. When the engine is knock limited, the engine runs at its inaudible knock limit. When the engine is misfire/partial-burn limited, the engine is maintained at its misfire/partial-burn limit. Three different embodiments of the closed loop MBT timing control architecture are disclosed: a cylinder-by-cylinder control, an average control and a mixed control.