Patent ID: 7954465
Filing Date: 2011-06-07
Classification: F02D

Abstract:
1. In an internal combustion engine having an engine valve for controlling gas flow between a cylinder and an engine manifold, a variable valve actuation system for actuating said engine valve, and a variable exhaust gas restriction device for restricting the flow of exhaust gas out of an exhaust manifold, a method of providing a selective level of brake gas recirculation to achieve a desired level of engine braking power or a selective level of exhaust gas recirculation to achieve a desired level of NOx production, through the combined control of engine variable valve actuation and variable exhaust gas restriction, said method comprising the steps of: determining one or more engine operating parameters selected from the group consisting of engine speed, engine load, exhaust manifold pressure, and vehicle speed; determining both a desired actuation timing for the engine valve using the variable valve actuation system and a desired level of exhaust gas restriction for the exhaust gas restriction device based on the one or more determined engine operating parameters to provide a selective level of brake gas recirculation or a selective level of exhaust gas recirculation; and providing the desired level of exhaust gas restriction and the desired actuation timing for the engine valve required to provide the selective level of brake gas recirculation or the selective level of exhaust gas recirculation.