Method and system for engine control
AssigneeFord Global Technologies, LLC
InventorsKenneth James Miller, Thomas G. Leone, Douglas Raymond Martin
Life of this patent
Estimating the term…
Abstract
Methods and systems are provided for integrating a bi-fuel engine with a CVT transmission. Responsive to a driver demand, a controller may determine whether to maintain usage of a current fuel or transition to an alternate fuel based on the cost efficiency of the transition and further based on any engine limitations that may be incurred at the engine speed-load following the transition. To improve the net fuel economy benefit while addressing the engine limitation, a fuel transition may be combined with a CVT adjusted engine speed-load regime, while maintaining engine power output.
Claims20
A method for a multi-fuel engine coupled with a continuously variable transmission (CVT), comprising:
- for a power level, comparing engine cost efficiency with a current fuel to engine cost efficiency with an alternate fuel at an adjusted engine speed-load based on output of sensors of engine operating parameters;
- and
- in response to a higher than threshold improvement in the cost efficiency with the alternate fuel at the adjusted engine speed-load, transitioning to the alternate fuel via a controller sending a signal to an actuator coupled to a fuel injector delivering the alternate fuel to a cylinder to activate the fuel injector and changing to the adjusted engine speed-load.
A method for an engine coupled with a continuously variable transmission (CVT), comprising:
- for a driver demand determined based on output of a pedal position sensor coupled to an operator pedal,
- estimating a first cost efficiency associated with maintaining a first fuel and a second cost efficiency associated with transitioning to a second fuel while operating with a knock-adjusted and friction-adjusted engine speed-load profile;
- and
- in response to the second cost efficiency being higher than the first cost efficiency, transitioning to usage of the second fuel via a controller sending a signal to an actuator coupled to a fuel injector delivering the second fuel to a cylinder to activate the fuel injector and transitioning to the knock-adjusted and friction-adjusted engine speed-load profile via adjustments to a speed ratio of the CVT.
A vehicle system, comprising:
- an engine with a cylinder;
- a first fuel injector for delivering a first fuel from a first fuel tank into the cylinder;
- a second fuel injector for delivering a second fuel from a second fuel tank into the cylinder, the second fuel having a different alcohol content than the first fuel;
- a continuously variable transmission (CVT) coupling the engine to vehicle wheels, the CVT having a plurality of speed ratios;
- and
- a controller with computer readable instructions stored on non-transitory memory for:
- estimating a first cost efficiency associated with maintaining usage of the first fuel and a second cost efficiency associated with transitioning to usage of the second fuel;
- and
- if the second cost efficiency with a modified engine speed-load profile is higher than the first cost efficiency, activating the second fuel injector while deactivating the first fuel injector to transition to the second fuel while selecting one of the plurality of speed ratios of the CVT to provide the modified engine speed-load profile.
Dependencies are inferred from the claim text.