Air and fuel supply system for combustion engine

A variable compression ratio internal combustion engine, comprising:

• an engine block defining at least one cylinder;
• a head connected with said engine block, including an air intake port, and an exhaust port;
• a piston slidable in each cylinder;
• a combustion chamber being defined by said head, said piston, and said cylinder;
• an air intake valve controllably movable to open and close the air intake port;
• an air supply system including at least one turbocharger fluidly connected to the air intake port;
• an exhaust gas recirculation (EGR) system operable to controllably provide a portion of exhaust gas from the exhaust port to the air supply system;
• a fuel supply system operable to controllably inject fuel into the combustion chamber at a selected timing;
• a variable intake valve closing mechanism configured to keep the intake valve open by selective operation of the variable intake valve closing mechanism;
• and
• a controller configured to operate the intake valve to remain open for a portion of a second half of a compression stroke.

A method of controlling an internal combustion engine having a variable compression ratio, said engine having a block defining a cylinder, a piston slidable in said cylinder, a head connected with said block, said piston, said cylinder, and said head defining a combustion chamber, the method comprising:

• pressurizing a mixture of air and recirculated exhaust gas;
• supplying said air and exhaust gas mixture to an intake manifold of the engine;
• maintaining fluid communication between said combustion chamber and the intake manifold during a portion of an intake stroke and through a predetermined portion of a compression stroke;
• and
• supplying a pressurized fuel directly to the combustion chamber during a portion of a combustion stroke.