In start control for controlling an engine, a motor, and a clutch, a target throttle valve opening degree is set based on a rotational speed of the motor and a coolant temperature of the engine to control the engine such that the clutch is half-engaged to crank the engine by the motor, and fuel injection and ignition of the engine are started after a rotational speed difference between the rotational speed of the motor and a rotational speed of the engine becomes smaller than a threshold value and the clutch is engaged.

In start control for controlling an engine, a motor, and a clutch, a target throttle valve opening degree is set based on a rotational speed of the motor and a coolant temperature of the engine to control the engine such that the clutch is half-engaged to crank the engine by the motor, and fuel injection and ignition of the engine are started after a rotational speed difference between the rotational speed of the motor and a rotational speed of the engine becomes smaller than a threshold value and the clutch is engaged.

A switchable powertrain comprises at least four points of freedom. The switchable powertrain comprises a main gear set configured for gear ratio selection, the main gear set comprising main gears coupled to a main shaft and second gears coupled to a second shaft. An adapter comprises a first selective coupling configured to selectively couple to the main shaft, and a second selective coupling configured to selectively couple to the second shaft. A first torque source and a clutch are configured for selectively coupling or decoupling first torque to the main shaft. A second torque source is configured for selectively outputting second torque to the first selective coupling or to the second selective coupling.

A switchable powertrain comprises at least four points of freedom. The switchable powertrain comprises a main gear set configured for gear ratio selection, the main gear set comprising main gears coupled to a main shaft and second gears coupled to a second shaft. An adapter comprises a first selective coupling configured to selectively couple to the main shaft, and a second selective coupling configured to selectively couple to the second shaft. A first torque source and a clutch are configured for selectively coupling or decoupling first torque to the main shaft. A second torque source is configured for selectively outputting second torque to the first selective coupling or to the second selective coupling.

A battery discharge limit control system is provided. The system includes a motor driven by receiving the power stored in a battery and a clutch connected to the rotary shaft of the motor. Additionally, an engine includes the rotary shaft connected to the rotary shaft of the motor through the clutch and a transmission changes the rotational speed of the rotary shaft of the motor or the engine based on the input of the shift stage instruction to output the rotational speed to a driving wheel of a vehicle. A controller opens the clutch and drives the motor in the reverse rotation, when the input of the shift stage instruction is a reverse shift stage.

A vehicle includes a first rotary electric machine, a second rotary electric machine, and a control circuit. When the control circuit determines that a failure has occurred in the first rotary electric machine, the control circuit places the first rotary electric machine and a first transmission path as a power transmission path of the vehicle in the disconnection state, and places the second rotary electric machine and the first transmission path in the connection state. Further, when the control circuit determines that a failure has occurred in the second rotary electric machine, the control circuit places the first rotary electric machine and a first transmission path in the connection state, and place the second rotary electric machine and the first transmission path in the disconnection state.

Methods and systems are provided for using the weights of cost functions to improve linear-program-based vehicle driveline architectures and systems. In some embodiments, the methods and systems may include establishing values for driveline controls of a linear program based on driveline requests of the linear program. The values of the driveline controls, which may be used to adjust driveline actuators, may be established based on values of a plurality of weights of a cost function of the linear program, the weights respectively corresponding with the plurality of driveline requests.

Methods and systems are provided for using the weights of cost functions to improve linear-program-based vehicle driveline architectures and systems. In some embodiments, the methods and systems may include establishing values for driveline controls of a linear program based on driveline requests of the linear program. The values of the driveline controls, which may be used to adjust driveline actuators, may be established based on values of a plurality of weights of a cost function of the linear program, the weights respectively corresponding with the plurality of driveline requests.

Various embodiments include a method for operating a hybrid drive train for a motor vehicle having an output shaft from an internal combustion engine releasably connected to a shaft of an electric traction machine via a first clutch, wherein the shaft of the electric traction machine is releasably connected to a transmission input shaft via a second clutch. The method may comprise: determining a state parameter for the motor vehicle; and opening either the first clutch or the second clutch for a changeover to coasting operation of the hybrid drive train based on a function of one or more state parameters.

A method and system for controlling a stop rotation position of an engine is described. In one example, the system includes an integrated starter/generator that may be selectively coupled to the engine. The integrated starter/generator may rotate the engine in a first direction (e.g., reverse direction) or a second direction (e.g., a forward direction) in response to a position at which the engine stops rotating following cessation of combustion in the engine.