A hybrid vehicle includes two drive sources and two clutches, and is switchable between a neutral mode and a parallel mode during vehicle traveling. The two drive sources are both disconnected from drive wheels in the neutral mode, and are both connected to the drive wheels in the parallel mode. A control method for the hybrid vehicle includes implementing at least one of a first switching control and a second switching control. The first switching control includes, upon switching from the neutral mode to the parallel mode, implementing two synchronization controls on rotational speeds before and after the two clutches, concurrently during at least a partial period. The second switching control includes, upon switching from the parallel mode to the neutral mode, implementing two controls to cause transmitted torques of the two clutches to respectively approach zero, concurrently during at least a partial period.

In a hybrid vehicle, rotational speed control on a motor/generator connected to a first engagement clutch is carried out when there is a gear shift request to a gear shift stage at which the first engagement clutch of the multistage gear transmission is meshingly engaged. A transmission control unit is provided for outputting a meshing engagement instruction to the first engagement clutch when a rotational speed feedback control causes a differential rotation speed of the first engagement clutch to be within a range of a synchronization determination rotational speed. Upon executing the rotational speed feedback control on the motor/generator, this transmission control unit reduces the efficacy of the rotational speed feedback control less than before starting of the meshingly engagement, when the meshing engagement of the first engagement clutch is started.

A low-voltage hybrid powertrain system for a vehicle includes an engine that is coupled via an engine disconnect clutch to an input member of the transmission, and a low-voltage electric machine is coupled to the transmission. The powertrain system operates in an electric vehicle (EV) mode with the engine in an OFF state and with the engine disconnect clutch in an open/deactivated state. When an output torque request indicates a command for vehicle acceleration, the electric machine is controlled to generate torque in response to the output torque request and the engine is simultaneously cranked and started. Upon starting, the engine operates in a speed control mode to activate the engine disconnect clutch. The engine and the low-voltage electric machine are controlled to generate torque in response to the output torque request when the engine disconnect clutch is activated.

An AWD-vehicle control device includes a transfer clutch that adjusts a driving force, a detector that detects a steering angle of a steering wheel, a detector that detects an accelerator pedal opening, a detector that detects a vehicle speed, a detector that detects an engine revolution speed, a detector that detects a turbine revolution speed of a torque converter, and a transfer clutch controller that adjusts hydraulic pressure supplied to the transfer clutch and controls a coupling force of the transfer clutch. If a predetermined period has passed from the accelerator pedal opening becoming less than a predetermined opening, the vehicle speed is within a predetermined range, a deviation between the engine and turbine revolution speeds is less than a predetermined speed, and the steering angle is equal to a first predetermined angle or greater, the transfer clutch controller controls the hydraulic pressure to reduce the coupling force.

A vehicle control device in a vehicle including an engine and a multi-speed transmission having a plurality of gear positions, each gear position out of the plurality of gear positions established by engaging predetermined engagement devices out of a plurality of engagement devices, the vehicle control device including a shift control portion configured to control release of a release-side engagement device of the plurality of engagement devices and engagement of an engagement-side engagement device of the plurality of engagement devices so as to switch the gear position established in the multi-speed transmission, and an engine control portion configured to provide idling-reduction control of temporarily stopping the operation of the engine based on a predetermined engine stop condition.

A hybrid system includes a transmission control module, a power source, a transmission, and a drive train. The transmission control module partially operates the hybrid system and receives operating information from various components of the system, calculates power losses in the drive train, and calculates the driving torque needed to reach a target power profile determined from a driver's input.

Propulsion for a vehicle is provided by a hybrid powertrain that includes a torque converter coupled to an electric machine and selectively coupled to an engine. The hybrid powertrain further includes a controller programmed to, responsive to a loss of speed feedback of the electric machine while the engine is disconnected from the torque converter and the torque converter is open, operate one or more of a gearbox, the electric machine, and the engine based on an impeller speed of the torque converter derived from a torque of the electric machine and a speed of the vehicle.

A low-voltage hybrid powertrain system for a vehicle includes an engine that is coupled via an engine disconnect clutch to an input member of the transmission, and a low-voltage electric machine is coupled to the transmission. The powertrain system operates in an electric vehicle (EV) mode with the engine in an OFF state and with the engine disconnect clutch in an open/deactivated state. When an output torque request indicates a command for vehicle acceleration, the electric machine is controlled to generate torque in response to the output torque request and the engine is simultaneously cranked and started. Upon starting, the engine operates in a speed control mode to activate the engine disconnect clutch. The engine and the low-voltage electric machine are controlled to generate torque in response to the output torque request when the engine disconnect clutch is activated.

A hybrid system includes a transmission control module, a power source, a transmission, and a drive train. The transmission control module partially operates the hybrid system and receives operating information from various components of the system, calculates power losses in the drive train, and calculates the driving torque needed to reach a target power profile determined from a driver's input.

Systems and methods for operating a driveline of a hybrid vehicle are described. In one example, a torque that is produced by an engine is adjusted responsive to a transmission oil temperature and a speed of a torque converter impeller so that temperature of oil in a transmission lube circuit may be maintained at a desired temperature.