VARIABLE VALVE ACTUATION CONTROL SYSTEMS AND METHODS

• Main Authors: MARRIOTT CRAIG D, WILES MATTHEW A
• Format: Patent
• Language: English
• Published: 31.03.2011
• Subjects: BLASTING; COMBUSTION ENGINES; CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES; ENGINE PLANTS IN GENERAL; HEATING; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS; IGNITION, OTHER THAN COMPRESSION IGNITION, FORINTERNAL-COMBUSTION ENGINES; LIGHTING; MACHINES OR ENGINES IN GENERAL; MECHANICAL ENGINEERING; STEAM ENGINES; TESTING OF IGNITION TIMING IN COMPRESSION-IGNITION ENGINES; WEAPONS

A variable valve actuation (VVA) system comprises a spark control module and a phaser control module. The spark control module maintains a spark timing of a cylinder at a maximum braking torque (MBT) spark timing during engine idling. The phaser control module, during the engine idling, adjusts an intake valve timing of the cylinder away from a predetermined intake valve timing. The predetermined intake valve timing corresponds to a maximum air per cylinder (APC) for the cylinder at a current engine speed. The adjustment of the intake valve timing produces an APC that is less than the maximum APC.