Systems and methods for torque bump mitigation in a variable displacement engine
AssigneeFord Global Technologies, LLC
InventorChristopher Glugla
Life of this patent
Estimating the term…
Abstract
Methods and systems are provided for reducing or avoiding a torque bump resulting from unintended combustion in a deactivated cylinder of a variable displacement engine. In one example, a method includes reducing or avoiding a torque bump associated with an engine of a vehicle while one or more cylinders of the engine are deactivated by reducing a torque output of the engine by an amount substantially equivalent to a torque increase provided to the engine via the unintended combustion event. In this way, undesired torque bumps may be avoided when operating in VDE mode, which may improve customer satisfaction, and which may enable improved fuel economy and engine efficiency.
Claims19
A method, comprising:
- deactivating a subset of cylinders of a variable displacement engine while other cylinders of the engine combust air and fuel;
- reducing or avoiding a torque bump due to an unintended combustion event in a deactivated cylinder by reducing a torque output of the engine and reactivating the deactivated cylinder which had the unintended combustion event, wherein reducing the torque output of the engine includes reducing a torque contribution of an activated cylinder that is scheduled to combust air and fuel following the unintended combustion event;
- and
- during subsequent cylinder deactivation events, not deactivating the cylinder which had the unintended combustion event.
A method, comprising:
- with a first set of cylinders of an engine deactivated and with a second set of cylinders activated to combust air and fuel, monitoring acceleration of a crankshaft coupled to the engine and in response to acceleration of the crankshaft greater than a crankshaft acceleration threshold resulting from an unintended combustion event in a deactivated cylinder, retarding a spark provided via an activated cylinder included in the second set of cylinders, the activated cylinder comprising a cylinder scheduled to combust air and fuel immediately following the acceleration of the crankshaft greater than the crankshaft acceleration threshold;
- and
- reactivating the deactivated cylinder responsible for the acceleration of the crankshaft greater than the crankshaft acceleration threshold and deactivating a cylinder from the second set of cylinders.
A system for a vehicle, comprising:
- a variable displacement engine, including a set of cylinders and where each cylinder is coupled to a fuel injector and a spark plug, and where each cylinder includes a piston;
- a crankshaft mechanically coupled to the variable displacement engine;
- a crankshaft position sensor;
- and
- a controller, storing instructions in non-transitory memory that, when executed, cause the controller to:
- deactivate a first subset of cylinders that includes one or more cylinders from the set of cylinders in response to predetermined conditions being met, where deactivating the first subset of cylinders includes at least sealing and stopping providing fuel injection to the first subset of cylinders;
- maintaining a second subset of cylinders that includes one or more cylinders from the set of cylinders activated to combust air and fuel;
- monitor acceleration of the crankshaft while the first subset of cylinders is deactivated;
- and
- in response to acceleration of the crankshaft greater than a crankshaft acceleration threshold resulting from unintended combustion in a deactivated cylinder included in the first subset of cylinders, retarding a spark provided to an activated cylinder included in the second subset of cylinders, the activated cylinder comprising a cylinder scheduled to combust air and fuel immediately following the acceleration of the crankshaft greater than the crankshaft acceleration threshold, and assigning the first subset of cylinders to be reactivated to combust air and fuel and the second subset of cylinders to be deactivated, immediately following retarding the spark provided to the activated cylinder.
Dependencies are inferred from the claim text.