Hybrid vehicle and associated control method
AssigneeFord Global Technologies, LLC
InventorsQing Wang, Ming Lang Kuang, Philip Joseph Wiethe, Jeffrey Randolph Holmes, Ryan Abraham McGee, Fazal Urrahman Syed
Life of this patent
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Abstract
A hybrid vehicle and method of control are disclosed wherein the ratio of engine speed to vehicle speed varies continuously in some operating modes and is controlled to simulate a discrete ratio transmission in other operating modes. The disclosure specifies the method of controlling the engine speed and the combined output torque of the engine and at least one traction motor in each of the operating modes. Transitions among operating modes occur in response to driver movement of a shift lever, driver operation of shift selectors, and changes in vehicle speed.
Claims19
A hybrid electric vehicle comprising:
- an internal combustion engine;
- a continuously variable transmission having an input shaft drivably connected to the internal combustion engine, the transmission including at least one traction motor, the transmission having an output speed and an output torque;
- a driver operated range selector having first and second forward driving positions;
- driver operated upshift and downshift selectors;
- a driver operated accelerator pedal;
- and
- a controller in communication with the range selector, the upshift and downshift selectors, the accelerator pedal, the internal combustion engine, and the transmission, the controller operating the vehicle in multiple operating modes including
- a first mode (Normal), corresponding to the first position (D) of the range selector;
- a second mode (Sport), corresponding to the second position (S) of the range selector, wherein the controller operates the engine and motor to provide an output torque higher than in the first mode at substantially equal accelerator pedal position and vehicle speed;
- and
- a third mode (LID), activated from the first mode by operation of the downshift selector, wherein the controller controls engine speed to be proportional to output speed based on a selected virtual gear number.
A method for controlling a hybrid vehicle having a traction motor and an engine, comprising:
- when operating in a first mode (Normal), controlling the engine and traction motor to provide an output torque than varies based on vehicle speed and accelerator pedal position;
- when operating in a second mode (Sport) activated from first mode by movement of a range selector, controlling the engine and traction motor to provide higher output torque than in the first mode for corresponding vehicle speed and accelerator pedal position;
- and
- when operating in a third mode (LID) activated from the first mode by operation of a downshift selector, controlling the engine and traction motor such that the engine speed is proportional to vehicle speed.
A controller for a hybrid powertrain, wherein:
- the controller sends control signals to an engine and at least one traction motor resulting in an engine operating speed and an output torque;
- the controller responds to signals from a range selector with at least two forward driving positions, an upshift selector, a downshift selector, and an accelerator pedal;
- the controller operates in a first mode (Normal) when the range selector is moved to a first forward driving position;
- the controller transitions from the first mode to a second mode (Sport) when the range selector is moved to a second forward driving position, the controller operating the engine and the at least one traction motor to deliver a higher output torque in the second mode than in the first mode;
- and
- the controller transitions from the first mode to a third mode (LID) when the downshift selector is operated, the controller operating the engine and the at least one traction motor in the third mode such that the engine speed simulates the operation of a discrete ratio transmission.
Dependencies are inferred from the claim text.