Abstract:
A vehicle includes a powertrain having an electric machine configured to selectively apply regenerative braking torque to decelerate the vehicle. The vehicle also includes a controller programmed to control a rate of change of a regenerative braking torque limit during a transmission downshift that occurs during a regenerative braking event based on a change in speed of an output shaft of the powertrain caused by the transmission downshift.
Abstract:
Systems and methods for transitioning a torque source between speed control and torque control modes during a vehicle creep mode are disclosed. In one example, torque of an electric machine is adjusted in response to a torque converter model. The torque converter model provides for a locked or unlocked torque converter clutch.
Abstract:
A method according to an exemplary aspect of the present disclosure includes, among other things, controlling a torque output of an electric machine of an electrified vehicle based on estimated loads present during a transmission engagement of the electrified vehicle.
Abstract:
A powertrain comprising an engine, a motor, a disconnect clutch connected between the engine and the motor, and a transmission. The transmission is connected to the motor by a torque converter and lock-up clutch and selectively and indirectly connected to the engine by the disconnect clutch. A controller receives an engine torque output signal and reduces the torque output of the engine to the clutch capacity limit value. A system and a method are also provided for controlling a powertrain for a hybrid vehicle.
Abstract:
Systems and methods for operating a hybrid vehicle driveline that includes an engine and a motor are presented. In one example, the systems and methods include one or more speed control modes where torque output of a motor is adjusted responsive to different control parameters in the different control modes.
Abstract:
Systems and methods for improving hybrid vehicle performance and efficiency attributes are presented. In one example, an electric machine maximum available torque is controller limited so as to improve conservation of battery charge and driveline performance consistency. The electric machine torque may be limited as a function of driveline speed, battery discharge limit, and other parameters.
Abstract:
A hybrid vehicle includes an engine and an electric machine, both capable of propelling the vehicle. The electric machine is electrically connected to a high voltage traction battery. The state of charge of the battery can decrease if the battery is used to power the electric machine, and can increase if the electric machine supplies power to the battery via regenerative braking. Constraints are placed on the vehicle such that the battery operates within a preferred operating window, defined between minimum and maximum state of charge thresholds. At least one controller is programmed to alter the preferred operating window of the battery in response to various vehicular activities, such as when the vehicle is towing another object, or when the vehicle weighs above a certain threshold due to contents within the vehicle, for example.
Abstract:
A method according to an exemplary aspect of the present disclosure includes, among other things, controlling a torque output of an electric machine of an electrified vehicle during a vehicle creep condition, the torque output calculated based at least on a road grade estimate and a vehicle mass estimate.
Abstract:
Methods and systems are provided for improving engine restart operations responsive to a heavy operator pedal tip-in. Engine torque and disconnect clutch capacity are controlled during cranking and engine speed run-up so as to provide excess torque to accelerate the engine to the motor speed and prepare the engine for elevated torque delivery after the engine connects to the driveline. At a time of connecting the engine to the driveline, the engine torque is transiently reduced to avert NVH issues related to engine speed overshooting or undershooting the target speed.
Abstract:
A system and method for controlling a fraction motor in a hybrid vehicle includes varying a traction motor torque in response to an engine cylinder misfire. The traction motor torque is varied to compensate for an engine torque shortfall due to the engine cylinder misfire, reducing a torque imbalance caused by the misfire.