Patent ID: 9279376
Filing Date: 2016-03-08
CPC Classification: F02D,F02M,Y02T

Claim Text:
1. A control system for an engine, the control system comprising: a first module that estimates a total amount of exhaust gas recirculation (EGR) in the engine, wherein the total amount of EGR includes (i) EGR within cylinders of the engine and (ii) EGR flowing through an EGR system of the engine; and a second module that selectively controls an overlap of intake and exhaust valve timing in the engine based on (i) a position of an EGR valve of the EGR system and (ii) a comparison of the estimated total amount of EGR in the engine and an EGR threshold, wherein the second module commands the overlap of the intake and exhaust valve timing in the engine to a minimum overlap for a predetermined number of combustion cycles prior to commanding the overlap of the intake and exhaust valve timing in the engine to another overlap that is greater than the minimum overlap, and wherein the predetermined number of combustion cycles is based on (i) internal EGR while at a minimum overlap of intake and exhaust valve timing and (ii) a difference between the total amount of EGR and the EGR threshold.