摘要:
A variety of methods and arrangements are described for controlling transitions between firing fractions during skip fire or other dynamic firing level modulation operation of an engine. In general, actuator first transition strategies are described in which an actuator position (e.g., cam phase, TCC slip, etc.) is changed to, or close to a target position before a corresponding firing fraction change is implemented. When the actuator change associated with a desired firing fraction change is relatively large, the firing fraction change is divided into a series of two or more firing fraction change steps. A number of intermediate target selection schemes are described as well.
摘要:
An engine control system includes a cylinder control module that deactivates and reactivates a cylinder of an engine based on a driver torque request while an ignition system associated with the engine is in an on position. A firing order module selectively adjusts a firing order of the engine based on a time when the cylinder is reactivated.
摘要:
A method for operating an internal combustion engine includes providing a vehicle having an internal combustion gasoline engine including multiple cylinders and wherein the engine is capable of running on at least one of a plurality firing fractions, providing a vacuum offset (Offsetvac) to adjust airflow capacity for each of the plurality of firing fractions, determining a torque capacity of each of the plurality firing fractions and a plurality of available firing fractions that provides at least enough torque capacity to accommodate a current torque requested (Treq), determining a plurality of viable firing fractions of the plurality of available firing fractions, and determining and implementing an optimal firing fraction of the viable firing fractions if the optimal firing fraction provides enough fuel economy benefit over a current firing fraction.
摘要:
A ranking module determines N ranking values for N predetermined cylinder activation/deactivation sequences of an engine, respectively. N is an integer greater than or equal to two. A cylinder control module, based on the N ranking values, selects one of the N predetermined cylinder activation/deactivation sequences as a desired cylinder activation/deactivation sequence for cylinders of the engine. The cylinder control module also: activates opening of intake and exhaust valves of first ones of the cylinders that are to be activated based on the desired cylinder activation/deactivation sequence; and deactivates opening of intake and exhaust valves of second ones of the cylinders that are to be deactivated based on the desired cylinder activation/deactivation sequence. A fuel control module provides fuel to the first ones of the cylinders and disables fueling to the second ones of the cylinders.
摘要:
A cylinder control module: selects one of N predetermined cylinder activation/deactivation patterns as a desired cylinder activation/deactivation pattern for cylinders of an engine, wherein N is an integer greater than two; and activates and deactivates opening of intake and exhaust valves of first and second ones of the cylinders that are to be activated based on the desired cylinder activation/deactivation pattern, respectively. A fuel control module provides fuel to the first ones of the cylinders and disables fueling to the second ones of the cylinders. The cylinder control module further: determines M possible ones of the N cylinder activation/deactivation patterns, wherein M is an integer greater than or equal to one; selectively compares the M possible cylinder activation/deactivation patterns with the desired cylinder activation/deactivation pattern; and selectively updates the desired cylinder activation/deactivation pattern to one of the M possible cylinder activation/deactivation patterns.
摘要:
A system according to the principles of the present disclosure includes a cylinder activation module and a spark control module. The cylinder activation module selectively deactivates and reactivates a cylinder of an engine. The cylinder activation module deactivates the cylinder after intake air is drawn into the cylinder and before fuel is injected into the cylinder or spark is generated in the cylinder. When the cylinder is reactivated, the spark control module selectively controls a spark plug to generate spark in the cylinder before an intake valve or an exhaust valve of the cylinder is opened.
摘要:
A variety of methods and arrangements are described for controlling transitions between firing fractions during skip fire and potentially variable displacement operation of an engine. In general, cam first transition strategies are described in which the cam phase is changed to, or close to a target cam phase before a corresponding firing fraction change is implemented. When the cam phase change associated with a desired firing fraction change is relatively large, the firing fraction change is divided into a series of two or more firing fraction change steps—with each step using a cam first transition approach. A number of intermediate target selection schemes are described as well.
摘要:
A system according to the principles of the present disclosure includes a cylinder activation module and a spark control module. The cylinder activation module selectively deactivates and reactivates a cylinder of an engine. The cylinder activation module deactivates the cylinder after intake air is drawn into the cylinder and before fuel is injected into the cylinder or spark is generated in the cylinder. When the cylinder is reactivated, the spark control module selectively controls a spark plug to generate spark in the cylinder before an intake valve or an exhaust valve of the cylinder is opened.
摘要:
A ranking module determines N ranking values for N predetermined cylinder activation/deactivation sequences of an engine, respectively. N is an integer greater than or equal to two. A cylinder control module, based on the N ranking values, selects one of the N predetermined cylinder activation/deactivation sequences as a desired cylinder activation/deactivation sequence for cylinders of the engine. The cylinder control module also: activates opening of intake and exhaust valves of first ones of the cylinders that are to be activated based on the desired cylinder activation/deactivation sequence; and deactivates opening of intake and exhaust valves of second ones of the cylinders that are to be deactivated based on the desired cylinder activation/deactivation sequence. A fuel control module provides fuel to the first ones of the cylinders and disables fueling to the second ones of the cylinders.
摘要:
A cylinder control module: selects one of N predetermined cylinder activation/deactivation patterns as a desired cylinder activation/deactivation pattern for cylinders of an engine, wherein N is an integer greater than two; and activates and deactivates opening of intake and exhaust valves of first and second ones of the cylinders that are to be activated based on the desired cylinder activation/deactivation pattern, respectively. A fuel control module provides fuel to the first ones of the cylinders and disables fueling to the second ones of the cylinders. The cylinder control module further: determines M possible ones of the N cylinder activation/deactivation patterns, wherein M is an integer greater than or equal to one; selectively compares the M possible cylinder activation/deactivation patterns with the desired cylinder activation/deactivation pattern; and selectively updates the desired cylinder activation/deactivation pattern to one of the M possible cylinder activation/deactivation patterns.