Abstract: A powertrain system includes a transmission device operative to transfer power between an input member and a plurality of torque machines and an output member. The torque machines are connected to an energy storage device and the transmission device is operative in one of a plurality of operating range states. A method for controlling the powertrain system includes monitoring available power from the energy storage device, determining system constraints, determining constraints on an output torque to the output member based upon the system constraints and the available power from the energy storage device, determining an operator torque request, determining an output torque command based upon the constraints on the output torque and the operator torque request, and determining preferred torque commands for each of the torque machines based upon the output torque command.

Abstract: A hybrid powertrain system includes a transmission device operative to transfer power between an input member, a torque machine and an output member, the output member coupled to a driveline coupled to a wheel to transfer tractive torque therebetween. A method for controlling the hybrid powertrain system includes monitoring an operator torque request, determining an operating range state of the transmission device, determining a net output torque to the output member based upon the operator torque request, determining a lash state of the driveline, and determining a command for transferring output torque to the output member based upon the operating range state of the transmission device, the net output torque, and the lash state of the driveline.

Abstract: A method for controlling a powertrain system includes controlling a first power actuator based upon a set of power constraints for the first power actuator. The method further includes controlling a second power actuator based upon the set of power constraints for the second power actuator.

Abstract: A powertrain system includes an engine coupled to an input member of a transmission operative to transmit power between the input member, a torque machine and an output member. The torque machine is connected to an energy storage device. The engine is selectively operative in engine states comprising an engine-on state and an engine-off state. A method for controlling a powertrain system includes determining a first power range for output power of the energy storage device, commanding the engine to transition from a first engine state to a second engine state, and expanding the first power range of the energy storage device and controlling the torque machine based upon the expanded power range of the energy storage device during the transition from the first engine state to the second engine state.

Abstract: An internal combustion engine is connected to a transmission to transmit tractive power to a driveline. Engine coolant temperature is determined, and power output of the engine is adjusted based upon the coolant temperature and preferred coolant temperature range. The transmission is controlled to transmit tractive power to the driveline to meet an operator torque request based upon the adjusted power output of the engine.

Abstract: A method for controlling a powertrain includes monitoring a desired synchronous transmission shift during deceleration of an output member including a desired operating range state, monitoring an output speed, predicting output deceleration through the desired synchronous transmission shift, determining a penalty cost associated with the desired synchronous transmission shift based upon an input speed profile resulting from the predicted output deceleration and from the desired synchronous transmission shift, and executing the synchronous transmission shift based upon the penalty cost.

Abstract: A vehicle includes a powertrain system and a friction braking system communicating tractive torque with a driveline, the powertrain system including a torque machine, and an energy storage device connected to the torque machine, said torque machine communicating tractive torque with the driveline. A method for controlling regenerative braking and friction braking includes monitoring a vehicle operating point, determining a braking torque request, determining a regenerative braking motor torque ratio based upon the vehicle operating point wherein the regenerative braking motor torque ratio is non-linearly dependent on the vehicle operating point, and actuating the friction brake based upon the regenerative braking motor torque ratio and the braking torque request.

Abstract: An engine is coupled to an input member of a hybrid transmission and the hybrid transmission is operative to transfer torque between the input member and a torque machine and an output member to generate an output torque in response to an operator torque request. The torque machine is connected to an energy storage device. A method for controlling the engine includes determining a preferred input torque from the engine to the hybrid transmission based upon operator inputs to an accelerator pedal and a brake pedal, determining maximum and minimum allowable input torques from the engine to the hybrid transmission, controlling the engine at the preferred input torque when the preferred input torque is within the maximum and minimum allowable input torques, and controlling the engine based upon the maximum and minimum allowable input torques when the preferred input torque is outside one of the maximum and minimum allowable input torques.

Abstract: A method for controlling a transmission operative to transfer power between an input member and torque machines and an output member includes determining available power, motor torque constraints, and other constraints on torque transfer. Equations are provided, transformed to a second coordinate system and simultaneously solved. An achievable torque operating region is determined.

Abstract: A powertrain system includes a transmission operative to transfer power between an engine coupled to an input member and a plurality of torque machines and an output member, A method for controlling the powertrain system includes monitoring system operation and determining an output torque request, determining a closed loop speed error, determining motor torque offsets to the torque machines based upon the closed loop speed error, determining output torque constraints based upon the motor torque offsets and the system operation, determining an output torque command based upon the output torque request and the output torque constraints, determining preferred motor torque commands for the torque machines based upon the output torque command, reducing the preferred motor torque commands for the torque machines using the motor torque offsets to the torque machines, and adjusting the reduced preferred motor torque commands for the torque machines based upon the closed loop speed error.

Abstract: A method for operating a vehicle includes determining a transmission input speed, operating the transmission using the transmission input speed, and providing a braking torque request to cause braking of the vehicle according to a scheme selected from the group consisting of a first braking mode and a second braking mode. The transmission input speed and the transmission operating range state are dependent on said braking torque request in the first braking mode, and wherein the transmission operating state, but not the transmission input speed, is dependent on the braking torque request in the second braking mode.

Abstract: A hybrid powertrain system includes a transmission operative to transfer power between an input member and a torque machine and an output member coupled to a driveline coupled to a wheel including an actuable friction brake. The torque machine is operative to react torque transferred from the wheel through the driveline to the output member of the transmission. The torque machine is connected to an energy storage device.

Abstract: A hybrid transmission is operative to transfer power between an input member and first and second torque machines and an output member in a fixed gear operating range state. The first and second torque machines are connected to an energy storage device.

Abstract: A method to determine a limit torque associated with an electro-mechanical transmission includes determining electric motor torque constraints and battery power constraints. A limit torque function and a standard form of the limit torque function are determined. The limit torque function and the motor torque constraints and the battery power constraints are transposed to the standard form to determine a limit torque.

Abstract: A control method for vehicular hybrid powertrain system includes monitoring operator inputs to an accelerator pedal and a transmission gear selector, and determining an operator torque request based upon the operator inputs to the accelerator pedal and the transmission gear selector. Torque output from the electric machine is commanded based upon the operator torque request. Engine output is controlled based upon the operator torque request and the commanded torque output from the electric machine. Vehicle hood position is monitored and the engine output is controlled correlative to the operator input to the accelerator pedal when the monitored position of the vehicle hood is open and the operator input to the transmission gear selector is one of a PARK and a NEUTRAL position.

Abstract: A method for improving drivability of the powertrain system having an accelerator control includes determining a first transmission input speed having an associated first power loss and operating said transmission using said first transmission input speed. An operational parameter relating to said accelerator control is determined and a second transmission input speed responsive to said operational parameter and having an associated second power loss is determined. The value of at least one of said first and second power loss is biased based on said operational parameter. The first power loss is compared to said second power loss subsequent to the biasing. A third transmission input speed is determined and the transmission is operated using the third transmission input speed.

Abstract: A method for controlling a powertrain includes operating a transmission in a neutral operating range state, monitoring commands affecting an input speed, monitoring a tracked clutch slip speed, determining constraints on an input acceleration based upon the commands, determining a clutch slip acceleration profile based upon the constraints on the input acceleration, determining an input acceleration profile based upon the clutch slip acceleration profile, and controlling the powertrain based upon the clutch slip acceleration profile and the input acceleration profile.

Abstract: An engine is mechanically coupled to a transmission device, the transmission device operative to transfer mechanical power between the engine and a second power generating device and an output member. A method for controlling the engine includes monitoring an operator demand for power, selecting a preferred engine state, determining a preferred engine torque input to the transmission device when operating in the preferred engine state based upon the operator demand for power, determining constraints on the engine torque input to the transmission device based upon a capacity of the transmission device to react the engine torque input, and commanding operation of the engine to the preferred engine state and commanding the engine torque input to the transmission device based upon the preferred engine torque input and the constraints on the engine torque input.

Abstract: A method for controlling a powertrain system includes monitoring voltage of an energy storage device. The method further includes modifying a preferred voltage limit when the voltage of the energy storage device transgresses a trigger voltage limit, and determining the power constraint of a first power actuator based on the estimated output power of the energy storage device when the voltage of the energy storage device transgresses the preferred voltage limit.

Abstract: A method for controlling a powertrain including an transmission coupled to an engine and an electric machine and a hydraulic control system providing hydraulic flow to a cooling circuit of the electric machine, wherein the transmission is adapted to selectively transmit mechanical power to an output membe, includes monitoring a temperature of the electric machine, determining a cooling flow requirement for the cooling circuit based upon the temperature of the electric machine, comparing the cooling flow requirement to a threshold cooling flow, and requesting active electric machine cooling of the electric machine based upon the comparing.