Abstract: A method for stabilizing selection between a plurality of operating range states of an electro-mechanical multi-mode transmission configured to transfer torque among an engine, at least one electric machine, and a driveline includes requesting operation of the transmission in a preferred operating range state while a shift from a first operating range state to a second operating range state is in progress prior to achieving the second operating range state. Powertrain information is monitored and compared to a driver perception threshold only if a change of mind condition is detected. The shift to the second operating range state is avoided and a shift to the preferred operating range state is commanded if the powertrain information does not violate the driver perception threshold.

Abstract: A method of managing available operating states in an electrified powertrain includes: identifying a plurality of operating states; determining an allowable hardware operating speed range for each of the plurality of operating states; determining a real operating speed range for each of the plurality of operating states; determining an ideal operating speed range for each of the plurality of operating states, the ideal operating speed range being a subset of the allowable real operating speed range; indicating an operating state of the plurality of operating states as ideal-allowed if an actual output speed of the electrified powertrain is within the ideal operating speed range for that operating state; and commanding the electrified powertrain to operate within one of the operating states that is indicated as ideal-allowed.

Abstract: A microprocessor driven two dimensional search engine examines transmission operating points within a plurality of search range spaces and assists in determining properties associated with the driveline at various operating points within the space. The size of the space is reduced by rearrangement of data.

Abstract: A method for operating a powertrain system to transfer torque among an engine, torque machines, and a driveline in response to an output torque request includes executing a selection scheme to evaluate operating in a plurality of candidate powertrain states including a pseudo-electric vehicle (EV) range responsive to the output torque request. A respective minimum cost for operating the powertrain system in each of the candidate powertrain states including the pseudo-EV range is determined. A preferred powertrain state is selected, and is one of the candidate powertrain states including the pseudo-EV range associated with a minimum of the respective minimum costs. The powertrain system is controlled in the preferred powertrain state responsive to the output torque request.

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 method for operating a powertrain system to transfer torque among an engine, torque machines, and a driveline includes identifying a speed/torque search window responsive to a parameter affecting engine power output and the output torque request. A search is executed to determine a preferred engine operating point for operating the powertrain system in response to an output torque request. The search includes determining a candidate power cost associated with operating the powertrain system at the candidate engine torque and candidate engine speed for each of a plurality of candidate engine speeds and candidate engine torques within the speed/torque search window. A preferred engine operating point is determined as the candidate engine speed and the candidate engine torque associated with a minimum of the candidate power costs. Engine operation is controlled responsive to the preferred engine speed.

Abstract: A powertrain system includes an internal combustion engine, a multi-mode transmission, torque machines, and a driveline. A method for operating the powertrain system to transfer torque among the engine, torque machine, and driveline includes controlling operation of the powertrain system in a pseudo-gear range in response to an output torque request including operating the transmission in a variable mode transmission range and controlling a magnitude of torque output to the driveline in response to an output torque request and in proportion to a magnitude of input torque from the engine.

Abstract: A method for operating a powertrain system includes selecting a plurality of candidate transmission ranges associated with a present powertrain operating point and deselecting candidate transmission ranges not associated with the present powertrain operating point. A high resolution engine speed/torque search is executed for each of the selected candidate transmission ranges. A low resolution engine speed/torque search is executed for each of the deselected candidate transmission ranges. Each search is executed to determine a respective minimum power cost for operating the powertrain system in one of the candidate transmission ranges in response to an output torque request and output speed. A preferred transmission range is determined from the candidate transmission ranges. A preferred engine operating point is determined corresponding to the minimum power cost for the preferred transmission range.

Abstract: A method for operating a powertrain system including a multi-mode transmission configured to transfer torque among an engine, torque machines, and a driveline, includes executing a first search to determine a first engine operating point within an all-cylinder state and a corresponding operating cost for operating the powertrain system in response to an output torque request. A second search is executed to determine a second engine operating point within a cylinder deactivation state and a corresponding operating cost for operating the powertrain system in response to the output torque request. One of the first and second engine operating points is selected as a preferred engine operating point based upon the operating costs and the engine is controlled at the preferred engine operating point in the corresponding one of the all-cylinder state and the cylinder deactivation state.

Abstract: A method for operating a powertrain system to transfer torque among an engine, torque machines, and a driveline includes executing a search to determine a preferred engine operating point for operating the powertrain system in a transmission range in response to an output torque request. The search includes employing a candidate torque normalization ratio to determine a candidate engine torque from a normalized torque search space, and determining a candidate power cost associated with operating the powertrain system at the candidate engine torque for each of a plurality of candidate engine speeds within an input speed range and a plurality of candidate torque normalization ratios. A preferred engine speed is determined, and includes the candidate engine speed corresponding to the one of the candidate engine torques associated with a minimum of the candidate power costs. Engine operation is controlled responsive to the preferred engine speed.

Abstract: A powertrain system includes an internal combustion engine, a multi-mode transmission, torque machines, and a driveline. A method for operating the powertrain system to transfer torque among the engine, torque machine, and driveline includes controlling operation of the powertrain system in a pseudo-gear range in response to an output torque request including operating the transmission in a variable mode transmission range and controlling a magnitude of torque output to the driveline in response to an output torque request and in proportion to a magnitude of input torque from the engine.

Abstract: A method of modifying the charging target for the state-of-charge (SOC) of a hybrid vehicle battery in response to a sudden power draw includes determining that the hybrid vehicle has entered a steep grade environment, adjusting a power management scheme of the hybrid vehicle from a standard charging mode to an aggressive charging mode, and operating the hybrid vehicle operated using the adjusted power management scheme. The charging target may include both an immediate charging target and an ultimate charging target, where the immediate charging target is less than the ultimate charging target, and where adjusting a power management scheme from a standard charging mode to an aggressive charging mode includes increasing the immediate charging target.

Abstract: A method for stabilizing selection between a plurality of operating range states of an electro-mechanical transmission configured to transfer torque among an engine, at least one electric machine, and a driveline includes requesting execution of a shift from a first operating range state to a second operating range state. Costs associated with operating the transmission in each of the plurality of operating range states including the first and second operating range states are monitored and an energy differential between the first and second operating range states is determined based on the monitored costs. The shift from the first operating range state to the second operating range state is executed only if the energy differential achieves an integration threshold.

Abstract: A method for stabilizing selection between a plurality of operating range states of an electro-mechanical multi-mode transmission configured to transfer torque among an engine, at least one electric machine, and a driveline includes requesting operation of the transmission in a preferred operating range state while a shift from a first operating range state to a second operating range state is in progress prior to achieving the second operating range state. Powertrain information is monitored and compared to a driver perception threshold only if a change of mind condition is detected. The shift to the second operating range state is avoided and a shift to the preferred operating range state is commanded if the powertrain information does not violate the driver perception threshold.

Abstract: A method for operating a powertrain system including a multi-mode transmission configured to transfer torque among an engine, torque machines, and a driveline, includes executing a first search to determine a first engine operating point within an all-cylinder state and a corresponding operating cost for operating the powertrain system in response to an output torque request. A second search is executed to determine a second engine operating point within a cylinder deactivation state and a corresponding operating cost for operating the powertrain system in response to the output torque request. One of the first and second engine operating points is selected as a preferred engine operating point based upon the operating costs and the engine is controlled at the preferred engine operating point in the corresponding one of the all-cylinder state and the cylinder deactivation state.

Abstract: A method for operating a powertrain system to transfer torque among an engine, torque machines, and a driveline includes identifying a speed/torque search window responsive to a parameter affecting engine power output and the output torque request. A search is executed to determine a preferred engine operating point for operating the powertrain system in response to an output torque request. The search includes determining a candidate power cost associated with operating the powertrain system at the candidate engine torque and candidate engine speed for each of a plurality of candidate engine speeds and candidate engine torques within the speed/torque search window. A preferred engine operating point is determined as the candidate engine speed and the candidate engine torque associated with a minimum of the candidate power costs. Engine operation is controlled responsive to the preferred engine speed.

Abstract: A method for operating a powertrain system includes selecting a plurality of candidate transmission ranges associated with a present powertrain operating point and deselecting candidate transmission ranges not associated with the present powertrain operating point. A high resolution engine speed/torque search is executed for each of the selected candidate transmission ranges. A low resolution engine speed/torque search is executed for each of the deselected candidate transmission ranges. Each search is executed to determine a respective minimum power cost for operating the powertrain system in one of the candidate transmission ranges in response to an output torque request and output speed. A preferred transmission range is determined from the candidate transmission ranges. A preferred engine operating point is determined corresponding to the minimum power cost for the preferred transmission range.

Abstract: A multi-mode powertrain system employing a power-split configuration to transfer torque to a driveline includes an internal combustion engine fluidly coupled to an exhaust aftertreatment system having a catalytic device. A method for controlling the multi-mode powertrain system includes identifying permitted transition paths between a plurality of engine states. The plurality of engine states includes a default state, a pre-light-off state, a light-off state, and a post-light-off state. A preferred one of the plurality of engine states is selected in response to an output torque request and an operating temperature of the catalytic device. Engine operation is transitioned to the preferred one of the plurality of engine states via the permitted transition paths, and the engine is operated in the preferred one of the plurality of engine states.

Abstract: A multi-mode vehicular powertrain system includes an internal combustion engine fluidly coupled to an exhaust aftertreatment system including a catalytic device and an electric machine electrically coupled to a battery. A method for effecting light-off of the catalytic device includes monitoring an output torque request for the powertrain system and determining a preferred engine operating point having a minimum engine operating cost within a predetermined engine operating region for catalyst light-off. When a state-of-charge of the battery is not approaching a predetermined state-of-charge limit, operation of the engine is controlled to the preferred engine operating point and operation of the electric machine is controlled to a machine operating point wherein the combination of engine torque at the preferred engine operating point and electric machine torque at the machine operating point satisfies the output torque request.

Abstract: A method for operating a powertrain system to transfer torque among an engine, torque machines, and a driveline includes executing a search to determine a preferred engine operating point for operating the powertrain system in a transmission range in response to an output torque request. The search includes employing a candidate torque normalization ratio to determine a candidate engine torque from a normalized torque search space, and determining a candidate power cost associated with operating the powertrain system at the candidate engine torque for each of a plurality of candidate engine speeds within an input speed range and a plurality of candidate torque normalization ratios. A preferred engine speed is determined, and includes the candidate engine speed corresponding to the one of the candidate engine torques associated with a minimum of the candidate power costs. Engine operation is controlled responsive to the preferred engine speed.