摘要:
A vehicle includes an engine, a transmission, a clutch, and a controller. The clutch is configured to couple the engine and transmission during engine starts. The controller is programmed to, in response to an actual engine start time being greater than an upper threshold time for an engine start event, alter an engine start torque apply schedule for the clutch such that the actual engine start time is less than the upper threshold time for a next engine start event. The controller may be further programmed to, in response to the actual engine start time being less than a lower threshold time for the engine start event, alter the engine start torque apply schedule for the clutch such that the actual engine start time is greater than the lower threshold time for the next engine start event.
摘要:
A system and method for controlling a step-ratio transmission gearshift during a regenerative braking event for a hybrid vehicle having an engine selectively coupled to an electric machine and an automatic transmission control transmission input torque based on a measured shift profile and a target shift profile. A torque trim term may be added to the transmission input torque or electric machine output torque in response to a difference between the measured and target shift profiles. The torque trim term may be used to modify the transmission input torque to speed the shift up or shorten the shift time if the measured shift is progressing too slowly. Likewise, the torque trim term may be used to reduce the transmission input torque or electric machine output torque if the shift is progressing too quickly relative to the target shift profile.
摘要:
Methods and systems are provided for controlling a vehicle system including an engine that is selectively shut-down during engine idle-stop conditions, the vehicle system further including a hydraulically actuated transmission component. One example method comprises, during an idle-stop engine shut-down, adjusting a hydraulic actuation of the transmission component to adjust drag torque on the engine to stop the engine.
摘要:
Systems and methods for starting an engine of a hybrid vehicle are disclosed. The systems and methods disclosed may apply to series or parallel hybrid driveline configurations. In one example, engine cranking torque may be adjusted in response to a variety of operating conditions so that the engine may be started faster or slower.
摘要:
A method and a system for improving operation of an automatically started engine are described. In one example, slip of a disconnect clutch is adjusted to limit an amount of engine torque transferred to vehicle wheels. The method and system adjust disconnect clutch slip in response to transmission input shaft speed and/or engine combustion events.
摘要:
A parallel hybrid vehicle includes an engine and a motor separated along a driveshaft by a clutch. The motor can operate (either alone or in combination with the engine) to provide positive drive torque to the wheels. The motor can also act as a generator and provide negative torque when converting mechanical energy from the driveshaft into mechanical energy to be stored in a battery. The clutch selectively couples the motor to the engine. Torque and its effects on the clutch can vary dramatically when the motor changes from providing positive and negative torque, and vice versa, while the engine is running. At least one controller in the vehicle is programmed to, while the engine is running, initiate an increase in pressure at the clutch in response to an anticipated change in torque provided by the motor from positive to negative or from negative to positive.
摘要:
A hybrid electric vehicle includes an engine, an electric motor, a transmission gearbox, and a clutch selectively coupling the engine to the electric motor. Engine speed can drop dramatically when operating at high speeds during a scheduled shift event in the gearbox. To reduce the effects felt by the engine speed change, at least one controller is provided and programmed to slip the clutch when locked in response to a drive torque, estimated to be present upon completion of an anticipated shift event, exceeding available negative torque, such as regenerative torque and engine braking torque.
摘要:
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 control modes where engine and/or motor speed or torque is adjusted responsive to different control parameters during a vehicle launch from zero speed or a creep speed.
摘要:
A control system including a method and apparatus for operating a hybrid vehicle. A disconnect clutch selectively separates an electric machine from a combustion engine. If a wide open throttle or high torque command is requested and the combustion engine is shut down, a 12 volt starter may be used to start the combustion engine while disconnected from the electric machine and all of the electric machine torque available may be used for traction.
摘要:
Systems and methods for reducing driveline mode change busyness for a hybrid vehicle are presented. The systems and methods may delay a driveline mode change in response to a time since a change from a first desired vehicle speed to a second vehicle speed, or alternatively, driveline mode changes may be initiated in response to an estimated time to change from the first desired vehicle speed to the second desired vehicle speed.