Abstract: A multi-mode powertrain system is described, and includes an internal combustion engine having stop/start capability. A method for controlling the multi-mode powertrain system includes circulating coolant to a heater core via an engine fluidic circuit that includes a water jacket of the internal combustion engine when temperature of the coolant is less than an engine fluidic circuit upper temperature threshold and the engine is in an ON state. Coolant is circulated to the heater core via a bypass fluidic circuit that excludes the water jacket of the internal combustion engine when temperature of the coolant is greater than a bypass fluidic circuit lower temperature threshold when the engine is in an OFF state.

Abstract: A powertrain system for a vehicle is described, and includes an internal combustion engine mechanically coupled to an electric machine to generate propulsion torque and electric power storable on an energy storage device. A method for controlling the powertrain system includes determining a first desired powertrain output power associated with a road load and determining a second desired powertrain output power associated with a feed-forward state-of-charge (SOC) for the energy storage device. The internal combustion engine and the electric machine are controlled responsive to the first and second desired powertrain output powers.

Abstract: A torque-generating system includes one or more torque-generating devices, a transmission having an output member, and a controller. The controller executes a method to control an operation of the system when the output member is operating at zero output speed. The controller is programmed to determine a torque request level and an actual speed of the output member, and an effective speed of the output member, as a calibrated non-zero value, using the torque request level when the determined actual speed is zero. The controller calculates an effective power of the powertrain using the effective speed and torque request level. A control action is executed with respect to the powertrain using the calculated effective power, including transmitting powertrain control signals to the torque-generating device(s) to select an appropriate powertrain operating mode.

Abstract: A multi-mode powertrain system is described, and includes an internal combustion engine and electric machines operative to transfer mechanical power through a gear train to an output member coupled to a driveline, wherein the electric machines electrically connect to a battery. The method includes determining an audible noise-based maximum engine speed, wherein the internal combustion engine generates an audible noise that is less than a threshold noise level when operating at a speed that is less than the audible noise-based maximum engine speed. The electric machines and the internal combustion engine are controlled responsive to an operator torque request including controlling the engine speed to be less than the audible noise-based maximum engine speed when battery power is greater than a minimum threshold.

Abstract: A torque-generating system includes one or more torque-generating devices, a transmission having an output member, and a controller. The controller executes a method to control an operation of the system when the output member is operating at zero output speed. The controller is programmed to determine a torque request level and an actual speed of the output member, and an effective speed of the output member, as a calibrated non-zero value, using the torque request level when the determined actual speed is zero. The controller calculates an effective power of the powertrain using the effective speed and torque request level. A control action is executed with respect to the powertrain using the calculated effective power, including transmitting powertrain control signals to the torque-generating device(s) to select an appropriate powertrain operating mode.

Abstract: A multi-mode powertrain system is described, and includes an internal combustion engine and electric machines operative to transfer mechanical power through a gear train to an output member coupled to a driveline, wherein the electric machines electrically connect to a battery. The method includes determining an audible noise-based maximum engine speed, wherein the internal combustion engine generates an audible noise that is less than a threshold noise level when operating at a speed that is less than the audible noise-based maximum engine speed. The electric machines and the internal combustion engine are controlled responsive to an operator torque request including controlling the engine speed to be less than the audible noise-based maximum engine speed when battery power is greater than a minimum threshold.

Abstract: A multi-mode powertrain system is described, and includes an internal combustion engine having stop/start capability. A method for controlling the multi-mode powertrain system includes circulating coolant to a heater core via an engine fluidic circuit that includes a water jacket of the internal combustion engine when temperature of the coolant is less than an engine fluidic circuit upper temperature threshold and the engine is in an ON state. Coolant is circulated to the heater core via a bypass fluidic circuit that excludes the water jacket of the internal combustion engine when temperature of the coolant is greater than a bypass fluidic circuit lower temperature threshold when the engine is in an OFF state.

Abstract: A powertrain system for a vehicle is described, and includes an internal combustion engine mechanically coupled to an electric machine to generate propulsion torque and electric power storable on an energy storage device. A method for controlling the powertrain system includes determining a first desired powertrain output power associated with a road load and determining a second desired powertrain output power associated with a feed-forward state-of-charge (SOC) for the energy storage device. The internal combustion engine and the electric machine are controlled responsive to the first and second desired powertrain output powers.

Abstract: A method of controlling a transmission includes detecting an occurrence of a downshift in the transmission from a first gear ratio to a second gear ratio. A determination is made whether the vehicle is operating within a freeway speed range, and whether an accelerator pedal is depressed at least a minimum percentage of a fully depressed position. When the downshift from the high gear ratio to the low gear ratio is detected, the vehicle is operating within the freeway speed range, and the accelerator pedal is depressed at least the minimum percentage of the fully depressed position, a countdown timer is started to count down from a pre-defined time to zero. An upshift of the transmission from the second gear ratio to the first gear ratio is restricted while the countdown timer defines a time that is greater than zero.

Abstract: A method of controlling a transmission includes detecting an occurrence of a downshift in the transmission from a first gear ratio to a second gear ratio. A determination is made whether the vehicle is operating within a freeway speed range, and whether an accelerator pedal is depressed at least a minimum percentage of a fully depressed position. When the downshift from the high gear ratio to the low gear ratio is detected, the vehicle is operating within the freeway speed range, and the accelerator pedal is depressed at least the minimum percentage of the fully depressed position, a countdown timer is started to count down from a pre-defined time to zero. An upshift of the transmission from the second gear ratio to the first gear ratio is restricted while the countdown timer defines a time that is greater than zero.