Method and apparatus to control a transition between HCCI and SI combustion in a direct-injection gasoline engine

Method for transitioning engine operation between a controlled auto-ignition combustion mode and a spark-ignition combustion mode, comprising:

• adapting the engine to be selectively operative in one of a low-lift and a high-lift engine valve operation;
• monitoring engine speed and engine load;
• determining the engine speed is above a predetermined threshold;
• selectively deactivating fuel delivery to a portion of the cylinders and selectively increasing torque output from non-deactivated cylinders to achieve the operator torque request and operating the engine at the high-lift engine valve operation when the engine load is within a predetermined range.

Internal combustion engine, comprising:

• a multi-cylinder direct-injection engine, adapted to operate at an air/fuel ratio that is one of lean of stoichiometry and substantially stoichiometric, comprising:
• a variable valve lift control device selectively operative at one of low valve lift and high valve lift;
• a control module, adapted to monitor inputs from a plurality of sensing devices and control a plurality of actuators based upon predetermined control schemes and adapted to cutoff fuel delivery to a portion of the cylinders during ongoing operation;
• a control scheme, comprising a computer program encoded therein executable in the control module for controlling operation of the engine, the program comprising:
• code to monitor engine operation and an operator torque request;
• code to determine engine speed is above a predetermined threshold;
• code to effect a transition between a spark-ignition combustion mode and a controlled auto-ignition combustion mode based upon the engine operation when the engine speed is above the predetermined threshold;
• wherein the transition comprises:
• code to control air/fuel ratio substantially to stoichiometry;
• code to command variable valve lift to a high valve lift opening;
• code to deactivate the portion of the cylinders by cutting off fuel delivery thereto during ongoing operation;
• code to increase fuel delivery to the non-deactivated cylinders to meet the operator torque request;
• code to control spark-ignition timing and dwell;
• and,
• code to control throttle to a wide-open position.

Method to operate a multi-cylinder direct-injection engine, comprising:

• adapting the engine to selectively operate in one of a controlled auto-ignition combustion mode and a spark-ignition combustion mode;
• monitoring engine operation and an operator torque request;
• selectively deactivating fuel delivery to a portion of the cylinders and selectively increasing torque output from non-deactivated cylinders to achieve the operator torque request when the monitored engine operation is above a predetermined first threshold;
• adapting the engine to be selectively operative in one of a low-lift and a high-lift engine valve operation;
• and
• controlling the engine to the high-lift engine valve operation concurrent with the selective deactivation of fuel delivery to the portion of the cylinders.

Method to operate a multi-cylinder direct-injection engine, comprising:

• adapting the engine to selectively operate in one of a controlled auto-ignition combustion mode and a spark-ignition combustion mode;
• monitoring engine operation and an operator torque request;
• selectively deactivating fuel delivery to a portion of the cylinders and selectively increasing torque output from non-deactivated cylinders to achieve the operator torque request when the monitored engine operation is above a predetermined first threshold;
• adapting the engine to be selectively operative at an air/fuel ratio that is one of lean of stoichiometry and substantially stoichiometric;
• and
• controlling the engine to the substantially stoichiometric air/fuel ratio concurrent with the selective deactivation of fuel delivery to a portion of the cylinders.

Method to operate a multi-cylinder direct-injection engine, comprising:

• adapting the engine to selectively operate in one of a controlled auto-ignition combustion mode and a spark-ignition combustion mode;
• monitoring engine operation and an operator torque request;
• selectively deactivating fuel delivery to a portion of the cylinders and selectively increasing torque output from non-deactivated cylinders to achieve the operator torque request when the monitored engine operation is above a predetermined first threshold;
• and
• controlling throttle opening to a wide-open position concurrent with the selective deactivation of fuel delivery to a portion of the cylinders.

Method to operate a multi-cylinder direct-injection engine, comprising:

• adapting the engine to selectively operate in one of a controlled auto-ignition combustion mode and a spark-ignition combustion mode;
• monitoring engine operation and an operator torque request;
• selectively deactivating fuel delivery to a portion of the cylinders and selectively increasing torque output from non-deactivated cylinders to achieve the operator torque request when the monitored engine operation is above a predetermined first threshold;
• and
• selectively enabling fuel delivery to all of the cylinders when the operator torque request exceeds a second predetermined threshold.

Method to operate a multi-cylinder direct-injection engine, comprising:

• adapting the engine to selectively operate in one of a controlled auto-ignition combustion mode and a spark-ignition combustion mode;
• monitoring an engine speed/load operating point;
• and
• selectively deactivating fuel delivery to a portion of the cylinders and selectively operating in the spark-ignition combustion mode when the monitored engine speed/load operating point is within a predetermined speed/load region.