Method and system for valve operation control
AssigneeFord Global Technologies, LLC
InventorsWilliam Paul Perkins, Scott James Thompson
Life of this patent
Estimating the term…
Abstract
Methods and systems are provided for raising the speed of a hybrid electric vehicle operating in an electric-only mode. During conditions when the vehicle is driven only by an electric motor, vehicle speed may be raised by spinning the engine unfueled using power from a system battery, while adjusting valve operation to reduce engine pumping losses. In this way, vehicle speed may be raised more efficiently and without damaging rotating transmission components.
Claims19
A method of operating a hybrid vehicle system, comprising:
- during an engine-off mode with only an electric motor driving a wheel of the vehicle, raising vehicle speed while decreasing or maintaining a rotational speed of a rotating planetary gear transmission component by raising speed of the wheel by providing a drive force from the electric motor to the wheel while increasing speed of an unfueled engine coupled to the wheel while decreasing or maintaining a rotational speed of a rotating planetary gear transmission component;
- and
- adjusting a cylinder valve operation based on the engine speed.
A method of operating a vehicle system, comprising:
- during an electric-only mode of operation,
- raising vehicle speed above a threshold vehicle speed, while spinning an engine coupled to a driven wheel unfueled using a battery, by providing a drive force to the wheel from a motor coupled to the wheel;
- and
- positioning a cam phaser coupled to intake and/or exhaust valves of the engine to reduce airflow through the spinning engine.
A vehicle system, comprising:
- an engine;
- a cam phaser coupled to intake and/or exhaust cams of the engine;
- a transmission including a planetary gearset and one or more gear elements;
- a battery coupled to each of a motor and a generator, the engine, motor and generator each coupled through the transmission to a driven wheel;
- and
- a controller with code for,
- during an engine-off mode with only the motor driving the vehicle via the wheel,
- raising vehicle speed above a threshold vehicle speed by providing a drive force from the motor to the wheel while spinning the engine unfueled;
- and
- adjusting a position of the cam phaser based on a rotational speed of the unfueled engine.
Dependencies are inferred from the claim text.