Patent ID: 8925315
Filing Date: 2015-01-06
Classification: F01L,F02D,Y02T

Abstract:
1. A method for reducing turbolag in a turbocharged internal combustion engine comprising an inlet manifold, an exhaust manifold, an exhaust gas recirculation (EGR) line between the exhaust manifold and the inlet manifold and including an EGR valve, and a Variable Geometry Turbine (VGT) turbo unit, comprising the steps of: shifting the internal combustion engine from a stationary engine mode to a transient engine mode having a positive pressure difference wherein the positive pressure difference is a condition in which a pressure upstream of an inlet valve of the engine is higher than a pressure downstream of an outlet valve of the engine, fully closing the EGR valve at the positive pressure difference during the transient engine mode, repositioning guide vanes of the VGT turbo unit from a first position when in the stationary engine mode to a second, more open position at the positive pressure difference during the transient engine mode, and increasing an amount of air flowing from the inlet manifold to the exhaust manifold and thereby increasing acceleration of the VGT while the EGR valve is fully closed and the guide vanes of the VGT turbo unit are in the second position by increasing a duration of overlapping of at least one inlet valve and at least one outlet valve provided in a cylinder head of the internal combustion engine from a first duration when in the stationary engine mode to a second duration at the positive pressure difference during the transient engine mode.