Abstract: A powertrain system includes an internal combustion engine and an electric machine coupled via a torque transfer device to a transmission. A method for operating the powertrain system to transfer torque to a driveline includes establishing an operating torque security limit that is a default torque security limit. The operating torque security limit is set to an override limit when engine speed is less than a threshold speed. A torque security fault is detected only when a combined torque output from the internal combustion engine and the electric machine to the torque transfer device deviates from an operator torque request by an amount greater than the operating torque security limit.

Abstract: A method for operating a powertrain system including a torque machine coupled to a drive wheel of a vehicle includes determining a regenerative braking capacity of the powertrain system. In response to a net operator torque request including a braking torque request, a friction braking torque command to operate a friction brake system and a regenerative braking torque request for the torque machine are coincidentally generated, a torque command is generated for controlling operation of the torque machine in response to the regenerative braking torque request, and the friction braking torque command is adjusted by an amount corresponding to a difference between the braking torque request and the regenerative braking torque request.

Abstract: A powertrain system includes an internal combustion engine and an electric machine coupled via a torque transfer device to a transmission. A method for operating the powertrain system to transfer torque to a driveline includes establishing an operating torque security limit that is a default torque security limit. The operating torque security limit is set to an override limit when engine speed is less than a threshold speed. A torque security fault is detected only when a combined torque output from the internal combustion engine and the electric machine to the torque transfer device deviates from an operator torque request by an amount greater than the operating torque security limit.

Abstract: A method for operating a powertrain system including a torque machine coupled to a drive wheel of a vehicle includes determining a regenerative braking capacity of the powertrain system. In response to a net operator torque request including a braking torque request, a friction braking torque command to operate a friction brake system and a regenerative braking torque request for the torque machine are coincidentally generated, a torque command is generated for controlling operation of the torque machine in response to the regenerative braking torque request, and the friction braking torque command is adjusted by an amount corresponding to a difference between the braking torque request and the regenerative braking torque request.