Patent ID: 8897975

Claim:
Method for controlling a powertrain system comprising an engine, a torque machine, a transmission device and an energy storage device, the transmission device configured to transfer power among the engine, the torque machine and an output member to generate an output torque, the method comprising: monitoring an operator torque request; selecting a candidate powertrain system operating point; determining a preferred engine torque range from a minimum engine torque to a maximum engine torque, a preferred torque machine torque range from a minimum torque machine torque to a maximum torque machine torque, and a preferred energy storage device output power range from a minimum energy storage device output power to a maximum energy storage device output power; determining an engine torque, a torque machine torque, and an energy storage device output power based upon the operator torque request and the candidate powertrain system operating point; determining power costs for operating the powertrain at the candidate powertrain system operating point based on the determined engine torque, the determined torque machine torque, and the determined energy storage device output power range; determining penalty costs associated with violating the preferred engine torque range, the preferred torque machine torque range, and the preferred energy storage device output power range for operating the powertrain at the candidate powertrain system operating point comprising determining an engine torque penalty cost based on a proximity of the engine torque to the violated one of the minimum engine torque and the maximum engine torque, determining a torque machine torque penalty cost based on a proximity of the torque machine torque to the violated one of the minimum torque machine torque and the maximum torque machine torque, and if the energy storage device output power is outside the preferred energy storage device output power range from the minimum energy storage device output power to the maximum energy storage device output power, determining an energy storage device output power penalty cost based on a proximity of the energy storage device output power to the violated one of the minimum energy storage device output power and the maximum energy storage device output power; and determining an operating cost for operating the powertrain at the candidate powertrain system operating point based on the power costs and the penalty costs, the penalty costs determined by summing the determined engine torque penalty cost, the determined torque machine torque penalty cost and the determined energy storage device output power penalty cost.