A hybrid vehicle with an engine and a rotary machine each coupled to a drive wheel in a power transmittable manner, comprises: an electronic control device that makes the rotary machine output a starting-time compensation torque to compensate a drop in a drive torque caused in a starting process of the engine in addition to a running torque when the engine is started while the vehicle is in a running state in which the drive torque is generated by the rotary machine and the engine is in a stopped state. The electronic control device starts the engine such that a starting-time inertia torque that is generated according to starting of the engine and causes the drop in the drive torque is made smaller when a torque margin of the rotary machine which is applied to the starting-time compensation torque is relatively small than when the torque margin is relatively large.

A method for operating a drive device for a motor vehicle, which has an internal combustion engine and an electric motor. A drive shaft of the internal combustion engine can be coupled to a motor shaft of the electric motor by a shift clutch. The shift clutch is adjusted to a desired clutch torque over a dragging period for startup of the internal combustion engine. Prior to the startup, a quantity of heat that is expected to accrue in the shift clutch during the startup is predicted and, when the predicted quantity of heat exceeds a limit value, at least one operating parameter of the drive device that influences the startup is chosen in such a way that the quantity of heat expected to accrue is reduced.

A power transmission device for a hybrid vehicle with a first clutch (1a) and a second clutch (1b). The first clutch (1a) is capable of transmitting or cutting off driving power of an engine (E) to driving wheels (D). The second clutch (1b) is capable of transmitting or cutting off power of a motor (M) to the driving wheels (D). The power transmission device is capable of appropriately operating the first clutch (1a) and the second clutch (1b) in accordance with driving conditions of the vehicle. When the engine (E) is started by transmitting power from the motor (M) to the engine (E), via the first clutch (1a) and the second clutch (1b), the power transmission device slip-controls the first clutch (1a) and the second clutch (1b).

A hybrid vehicle with an engine and a rotary machine each coupled to a drive wheel in a power transmittable manner, comprises: an electronic control device that makes the rotary machine output a starting-time compensation torque to compensate a drop in a drive torque caused in a starting process of the engine in addition to a running torque when the engine is started while the vehicle is in a running state in which the drive torque is generated by the rotary machine and the engine is in a stopped state. The electronic control device starts the engine such that a starting-time inertia torque that is generated according to starting of the engine and causes the drop in the drive torque is made smaller when a torque margin of the rotary machine which is applied to the starting-time compensation torque is relatively small than when the torque margin is relatively large.

A method for operating a drive device for a motor vehicle, which has an internal combustion engine and an electric motor. A drive shaft of the internal combustion engine can be coupled to a motor shaft of the electric motor by a shift clutch. The shift clutch is adjusted to a desired clutch torque over a dragging period for startup of the internal combustion engine. Prior to the startup, a quantity of heat that is expected to accrue in the shift clutch during the startup is predicted and, when the predicted quantity of heat exceeds a limit value, at least one operating parameter of the drive device that influences the startup is chosen in such a way that the quantity of heat expected to accrue is reduced.

An internal combustion engine is provided that executes fuel injection and ignition with respect to a cylinder that remains stopped in an expansion stroke, and that performs ignition startup that starts up the internal combustion engine by rotationally driving a crankshaft by pressure of combustion accompanying the fuel injection. A motor generator (MG) that can rotationally drive the crankshaft is provided. A required assist torque Ast_trq exerted by the MG at the time of ignition startup is determined based on a maximum value Cyl_prss of an in-cylinder pressure that is detected by an in-cylinder pressure sensor at the time of ignition startup. The MG is controlled at the time of ignition startup based on the required assist torque Ast_trq that is determined.

A power transmission device for a hybrid vehicle with a first clutch (1a) and a second clutch (1b). The first clutch (1a) is capable of transmitting or cutting off driving power of an engine (E) to driving wheels (D). The second clutch (1b) is capable of transmitting or cutting off power of a motor (M) to the driving wheels (D). The power transmission device is capable of appropriately operating the first clutch (1a) and the second clutch (1b) in accordance with driving conditions of the vehicle. When the engine (E) is started by transmitting power from the motor (M) to the engine (E), via the first clutch (1a) and the second clutch (1b), the power transmission device slip-controls the first clutch (1a) and the second clutch (1b).

A control device that controls a vehicle drive device. A starting control section executes internal combustion engine starting control in which the internal combustion engine in a stationary state is started while causing the disconnecting engagement device to transition from a disengaged state to a direct engagement state. A timing decision section that decides, on the basis of a rotational speed of the internal combustion engine, a supply start timing to start supply of a hydraulic pressure to a specific engagement device, which is one of the plurality of shifting engagement devices and is caused to transition from a disengaged state to a direct engagement state in order to establish a target shift speed for the speed change mechanism after a change, in the case where the target shift speed is changed during execution of the internal combustion engine starting control.

In a drive system, a first differential mechanism transmits engine rotation, a second differential mechanism connects the first differential mechanism with drive wheels, and a switching device changes a speed ratio of the first differential mechanism. The second differential mechanism has first, second, and third rotational elements, which connect respectively to the first differential mechanism, a first rotating machine, and a second rotating machine. In a first running condition, the vehicle runs using the second rotating machine as a power source, while differentially operating the first differential mechanism. In a second running condition, the vehicle runs using the second rotating machine as a power source, without differentially operating the first differential mechanism. A region in which the vehicle runs in the second running condition in the case where the engine cannot start by itself is larger than that in the case where the engine can start by itself.

A control device of a vehicle includes an engine, an electric motor, and a first clutch connecting/disconnecting a power transmission path between the engine and the electric motor, and a second clutch configured to achieve a mechanically directly-coupled state of a power transmission path between the engine/the electric motor and drive wheels, the control device of a vehicle increasing a torque of the electric motor and causing the second clutch to slip-engage when the engine is started by controlling the first clutch toward engagement during motor running using only the electric motor as a drive force source for running with the first clutch released and the second clutch engaged, when the torque of the electric motor increased at the start of the engine relative to the torque of the electric motor during the motor running is larger, a slip amount of the second clutch being made larger as compared to when the torque is smaller.