Engine management strategy
AssigneeFca US LLC
InventorSongping Yu
Life of this patent
Estimating the term…
Abstract
A system and method for controlling a vehicle to implement an engine torque management strategy. The engine torque management strategy implements a sophisticated engine knock control method that alleviates/mitigates the cause of the knock while also optimizing vehicle performance and engine efficiency without compromising engine hardware protection. Whenever suitable, the system and method attempt to reduce the amount of air trapped in a knocking cylinder to reduce its effective compression ratio and to eliminate the knock while keeping the same optimal spark timing for combustion efficiency.
Claims18
A method of controlling an engine system of a vehicle, the engine system including an engine having a plurality of cylinders, the method comprising:
- detecting, at a processor, engine knock in at least one cylinder of the plurality of cylinders;
- calculating, at the processor, knock density for each cylinder in which engine knock was detected, each knock density being indicative of an intensity of the detected engine knock in a corresponding cylinder;
- for each cylinder in which engine knock was detected:
- based on expected engine torque losses, determining, at the processor, whether to perform spark retardation or airflow reduction to decrease the engine knock in the cylinder, and
- based on the determining, performing, by the processor, spark retardation or airflow reduction for the cylinder, the airflow reduction being proportional to the cylinder's calculated knock density;
- and
- for each cylinder in which engine knock was not detected:
- increasing, by the processor, airflow into the cylinder.
An engine torque management system of a vehicle including an engine having a plurality of cylinders, the system comprising:
- at least one knock sensor associated with at least one cylinder of the plurality of cylinders;
- and
- a controller connected to the at least one knock sensor, the controller being configured to:
- detect engine knock in at least one cylinder of the plurality of cylinders;
- calculate knock density for each cylinder in which engine knock was detected, each knock density being indicative of an intensity of the detected engine knock in a corresponding cylinder;
- for each cylinder in which engine knock was detected:
- based on expected engine torque losses, determine whether to perform spark retardation or airflow reduction to decrease the engine knock in the cylinder, and
- based on the determination, perform spark retardation or airflow reduction for the cylinder, the airflow reduction being proportional to the cylinder's calculated knock density;
- and
- for each cylinder in which engine knock was not detected:
- increase airflow into the cylinder.
Dependencies are inferred from the claim text.