Method and apparatus for controlling transitions in an engine having multi-step valve lift

Method for controlling airflow into an internal combustion engine selectively operative at one of a first engine valve lift position and a second engine valve lift position during a transition therebetween, the method comprising:

• adapting the engine to control phasings of the engine valves;
• determining a desired engine airflow based upon an operator torque request;
• determining a cylinder intake volume for the desired engine airflow when operating at the first valve lift position;
• determining a valve control scheme to attain the cylinder intake volume for the desired engine airflow when operating at the second valve lift position;
• and,
• shifting to the second valve lift position and executing the valve control scheme when the cylinder intake volume to operate at the second valve lift position is within a range of authority of the controlled phasings of the engine valves.

Method for controlling an internal combustion engine during a transition between a spark-ignition combustion mode and a controlled auto-ignition combustion mode, the internal combustion engine including a controllable two-step valve lift system and a variable cam phasing system operative to control openings and closings of intake and exhaust valves, the method comprising:

• monitoring engine operation and an operator torque request;
• commanding a transition between the spark-ignition combustion mode and the controlled auto-ignition combustion mode based upon the engine operation;
• commanding the two-step valve lift system to shift from a first valve lift position to a second valve lift position;
• determining a desired engine airflow based upon an operator torque request;
• determining a cylinder intake volume for the desired engine airflow when operating at a first open position;
• determining a control scheme to control the openings and closings of the engine valves to attain the cylinder intake volume for the desired engine airflow when operating at the second valve lift position;
• and,
• executing the control scheme and transitioning to the second valve lift position when the cylinder intake volume to operate at the second valve lift position is within a range of authority of the engine valves.

Method for controlling engine valves of an internal combustion engine adapted to selectively operate at one of a first open position and a second open position, the method comprising:

• determining a desired engine airflow based upon an operator torque request;
• determining a cylinder intake volume for the desired engine airflow for the one of the first and second open positions that is operative;
• determining a control scheme to control the engine valves to attain the cylinder intake volume for the desired engine airflow for the one of the first and second open positions that is inoperative;
• and,
• executing the control scheme and transitioning the engine valves to the inoperative one of the first and second open positions when the cylinder intake volume for the desired airflow for the one of the first and second open positions that is inoperative is within a range of authority of the engine valves.