Methods and systems are provided for operating a driveline of a hybrid vehicle that may include an internal combustion engine, a rear drive unit electric machine, an integrated starter/generator, and a transmission are described. In one example, torque capacity of an on-coming clutch is adjusted during an inertia phase of a power-on upshift to improve shift smoothness.

A shift control system for vehicle that improves an acceleration feeling while suppressing a shift shock includes a controller that controls a transmission and a hydraulic controller. The controller, during an inertia phase where an input speed of the transmission changes toward a synchronous speed in a gear stage after a shift, sets an oil pressure of a specific frictional engagement device configuring the gear stage after the shift, of a plurality of frictional engagement devices to an oil pressure that, at a time of the shift, exceeds a first oil pressure to set a transmission torque capacity equal to a first drive torque applied to the specific frictional engagement device of a drive torque outputted from a prime mover, but is less than a second oil pressure to set a transmission torque capacity equal to a second drive torque which is the first drive torque to which has been added an inertia torque generated by inertia on a prime mover side accompanying a change in speed ratio.

Systems and methods are shown for meeting wheel torque demand in a hybrid vehicle with an engine, a dual clutch transmission coupled to a driveline of the vehicle downstream of the engine, and an electric machine coupled to the driveline downstream of the dual clutch transmission. In one example, a method comprises transferring transmission input torque through a clutch of the dual clutch transmission controlled to a first capacity, and in response to a desired transmission input torque exceeding the capacity, increasing torque output of the electric machine coupled downstream of the dual clutch transmission to assist in meeting a wheel torque demand. In this way, a driver-requested increase in acceleration may be met under conditions where transmission input torque is limited by clutch capacity.

An electronic control unit controls a motor so that a torque applied to an input shaft does not exceed an upper limit torque. The electronic control unit sets so as to restrict the upper limit torque from a first torque to a second torque smaller than the first torque, and then return the upper limit torque to the first torque more gradually when a first condition that a driver is assumed to have felt a decrease in driving force output to driving wheels is met before the upper limit torque is returned than when the first condition is not met.

This invention pertains to the field of power transmission. Machines using a power transmission mechanism for transmission of the mechanical power produced by a source (engine (2), electric motor, pneumatic and hydraulic pump) to another component of the machine (wheel (21), electric motor, electric generator, pneumatic and hydraulic pump) through multiple transmission paths (different gear ratios (14), (15)) are subjects of this invention. It is disclosed that control of a switching from one power transmission path to another is done in a manner involving simultaneous load transfer and speed synchronization rather than sequential performance of these two functions, and the resulting method developed in the invention leads to switching operations that produce less disturbance at the input of the said component. The said method is applied to the problem of controlling gearshifts in automatic transmissions of ground vehicles.

A hybrid vehicle includes an engine, an electric machine, a transmission, and a controller. The transmission is configured to alter clutch pressures in preparation for an upcoming shift between discrete gear ratios (e.g., input-to-output ratio). For example, the clutch pressures may spike to a heightened magnitude to prepare for the upcoming shift. The electric machine is configured to selectively propel the vehicle and perform regenerative braking. If regenerative braking demands occur during the clutch pressures being heightened during shift preparation, the controller is programmed to stop the preparing of the clutches. This can be done by reducing the clutch pressures back to their pre-preparation magnitude. The upcoming shift can be cancelled or delayed.

A hydraulic pressure control device for a continuously variable transmission of a vehicle which a continuously variable transmission mechanism; a stepwise variable transmission mechanism; a shift control means, the hydraulic pressure control device includes: the shift control means including a line pressure control section configured to increase the line pressure to be greater than the line pressure before a generation of an oil vibration when the oil vibration is generated in at least one of actual hydraulic pressures of the primary pressure and the secondary pressure, and the line pressure control section being configured to continue the increase of the line pressure until the shift of the stepwise variable transmission mechanism is finished when the stepwise variable transmission is shifted in a state where the line pressure is increased.

A control apparatus for a hybrid vehicle provided with an engine and a motor/generator functioning as a drive power source, an automatic transmission which constitutes a part of a power transmitting path between the drive power source and drive wheels and in which a shifting action is performed by selective engagement of a plurality of coupling devices, and an electric storage device giving/receiving electric power to/from the motor/generator, the control apparatus comprising: a hybrid control portion configured to control an input torque to the automatic transmission by the motor/generator during a shifting action of the automatic transmission on the basis of an output torque of the engine and a transmitted torque of the coupling devices, such that a value representing a rotating state of an input rotary member of the automatic transmission coincides with a target value; a racing determining portion configured to determine whether a rotating speed of the engine is predicted to exceed a predetermined rotating speed when control is provided such that the value representing the rotating state of the input rotary member of the automatic transmission coincides with the target value during a power-on shift-down action of the automatic transmission; and an output limiting portion configured to limit the output torque of the engine to a predetermined torque or less if the rotating speed of the engine is predicted to exceed the predetermined rotating speed during the power-on shift-down action of the automatic transmission.

A system and a method of controlling a hybrid electric vehicle shift are disclosed. The system includes an engine and a drive motor operating as power sources and a transmission receiving driving torque from one of the engine and the drive motor. A data detector detects a state data for operating the transmission. A vehicle controller calculates a creep torque and an engine setting torque using the state data, determines whether a shift control condition is satisfied based on a position value of an accelerator pedal, calculates an available motor torque using a motor speed at an actual shift start point and a target motor speed when the shift control condition is satisfied, and calculates a first shift input torque using the creep torque, the engine setting torque, the available motor torque, and a first torque apply ratio. The transmission is operated based on the first shift input torque.

A method controls an internal combustion engine that has a drive output shaft connected to an input shaft of a transmission. The internal combustion engine, the transmission and a drive wheel are encompassed by a drivetrain for the drive of a motor vehicle. The method includes determining a rotational acceleration of the input shaft and determining an input torque at the input shaft of the transmission based on a product of the rotational acceleration and a speed reduction ratio-dependent moment of inertia of the drivetrain in a section between the input shaft and the drive wheel. A combustion torque of the internal combustion engine is controlled such that the input torque adheres to a predetermined maximum input torque at the input shaft of the transmission.