Abstract: Calibration of an engine disconnect clutch for a hybrid electric powertrain. The clutch is prestroked while an engine and machine are stopped. A machine torque is increased until the machine starts rotating. A pressure of the clutch is adjusted as a function of a torque produced by the machine when the machine started rotating.

Abstract: Regenerative torque is limited for a hybrid electric powertrain of a vehicle. A transmission controller determined torque limit is validated by a vehicle controller. The vehicle controller validates the torque limit using, individually or in combination, an actual status of a torque converter clutch, a detected status of the torque converter clutch, or a speed of the vehicle.

Abstract: A hybrid electric automotive powertrain includes an engine start/stop system to improve fuel economy. The stop routine provides for quick restarting to avoid delay in a driver change of mind case. The stop routine may be terminated prior to full engine stop when a torque request is received during the stop routine.

Abstract: A method of smoothing hybrid vehicle engine shutdown. A powered and rotating electric machine is used to slow deceleration of an unpowered and rotating engine by transferring torque through a clutch from the machine to the unpowered engine. Prior to the machine being powered, torque may be transferred through the clutch from the unpowered and rotating engine to the unpowered machine to accelerate passage of the engine through a resonance frequency.

Abstract: Calibration of an engine disconnect clutch for a hybrid electric powertrain. The clutch is prestroked while an engine and machine are stopped. A machine torque is increased until the machine starts rotating. A pressure of the clutch is adjusted as a function of a torque produced by the machine when the machine started rotating.

Abstract: Regenerative torque is limited for a hybrid electric powertrain of a vehicle. A transmission controller determined torque limit is validated by a vehicle controller. The vehicle controller validates the torque limit using, individually or in combination, an actual status of a torque converter clutch, a detected status of the torque converter clutch, or a speed of the vehicle.

Abstract: A method for controlling a vehicle regenerative braking event includes maintaining a converter clutch closed while braking, while an engine connected to the impeller is running, opening the converter clutch when impeller speed reaches a reference speed difference relative to engine idle speed, and while the engine is off, opening the converter clutch when impeller speed reaches a speed required for a transmission pump, connected to an impeller, to produce line pressure at a desired magnitude.

Abstract: A hybrid electric automotive powertrain includes an engine start/stop system to improve fuel economy. The stop routine provides for quick restarting to avoid delay in a driver change of mind case. The stop routine may be terminated prior to full engine stop when a torque request is received during the stop routine.

Abstract: A method of smoothing hybrid vehicle engine shutdown. A powered and rotating electric machine is used to slow deceleration of an unpowered and rotating engine by transferring torque through a clutch from the machine to the unpowered engine. Prior to the machine being powered, torque may be transferred through the clutch from the unpowered and rotating engine to the unpowered machine to accelerate passage of the engine through a resonance frequency.

Abstract: A method for controlling a vehicle regenerative braking event includes maintaining a converter clutch closed while braking, while an engine connected to the impeller is running, opening the converter clutch when impeller speed reaches a reference speed difference relative to engine idle speed, and while the engine is off, opening the converter clutch when impeller speed reaches a speed required for a transmission pump, connected to an impeller, to produce line pressure at a desired magnitude.

Abstract: A powertrain includes a gearset including a sun gear, a carrier, a ring gear connected to a countershaft, pinions supported on the carrier and meshing with the sun gear and ring gear; a second gearset connectable to an engine, for overdriving a generator; a clutch for releasably connecting the engine and carrier; a second clutch for releasably connecting the sun gear and the generator; and a motor connected to a countershaft. Operation of the powertrain can be readily switched between powersplit mode and series mode.

Abstract: In a plug-in hybrid electric vehicle (PHEV), the vehicle may be operated in a charge-depleting (CD) mode to ensure that the battery is effectively discharged or in a charge-sustaining (CS) mode in which the battery state of charge is maintained by operating the internal combustion engine predominantly for propulsion. In trips that are longer than that which fully depletes the battery storage, it is possible to control the proportion in a manner that is between CS and CD modes to provide overall higher efficiency while still effectively discharging the battery over the course of the trip. Such higher efficiency operation is possible when information about the distance until the next charging event is available.

Abstract: A powertrain includes a gearset including a sun gear, a carrier, a ring gear connected to a countershaft, pinions supported on the carrier and meshing with the sun gear and ring gear; a second gearset connectable to an engine, for overdriving a generator; a clutch for releasably connecting the engine and carrier; a second clutch for releasably connecting the sun gear and the generator; and a motor connected to a countershaft. Operation of the powertrain can be readily switched between powersplit mode and series mode.

Abstract: In a hybrid electric motor vehicle , a power supply system for storing and supplying electrical power includes a motor-generator located onboard the vehicle, driveably connected to the vehicle wheels and producing AC electric power, an energy storage device for alternately storing and discharging electric power, an inverter coupled to the motor-generator and the energy storage device for converting alternating current produced by the motor-generator to direct current transmitted to the energy storage device, and for converting direct current stored in the energy storage device to alternating current transmitted to the motor-generator, an off board source of AC electric power located external to the vehicle, and a charger coupled to said electric power source and the energy storage device for supplying DC electric power to the energy storage device from said AC electric power source.

Abstract: A method for launching a vehicle includes determining that vehicle speed is less than a reference, demanded wheel power is less than a reference wheel power, and demanded engine power is less than a reference engine power; charging a battery using a generator driven by an engine; using an electric machine powered by the battery to drive vehicle wheels; and opening a clutch located in a drive path between a transmission and the generator.

Abstract: In a plug-in hybrid electric vehicle (PHEV), the vehicle may be operated in a charge-(CD) mode to ensure that the battery is effectively discharged or in a charge-sustaining (CS) mode in which the battery state of charge is maintained by operating the internal combustion engine predominantly for propulsion. In trips that are longer than that which fully depletes the battery storage, it is possible to control the proportion in a manner that is between CS and CD modes to provide overall higher efficiency while still effectively discharging the battery over the course of the trip. Such higher efficiency operation is possible when information about the distance until the next charging event is available.

Abstract: In a hybrid electric motor vehicle , a power supply system for storing and supplying electrical power includes a motor-generator located onboard the vehicle, driveably connected to the vehicle wheels and producing AC electric power, an energy storage device for alternately storing and discharging electric power, an inverter coupled to the motor-generator and the energy storage device for converting alternating current produced by the motor-generator to direct current transmitted to the energy storage device, and for converting direct current stored in the energy storage device to alternating current transmitted to the motor-generator, an off board source of AC electric power located external to the vehicle, and a charger coupled to said electric power source and the energy storage device for supplying DC electric power to the energy storage device from said AC electric power source.

Abstract: In a hybrid electric motor vehicle, a power supply system for storing and supplying electrical power includes a motor-generator located onboard the vehicle, driveably connected to the vehicle wheels and producing AC electric power, an energy storage device for alternately storing and discharging electric power, an inverter coupled to the motor-generator and the energy storage device for converting alternating current produced by the motor-generator to direct current transmitted to the energy storage device, and for converting direct current stored in the energy storage device to alternating current transmitted to the motor-generator, a source of AC electric power located external to the vehicle, and a charger coupled to said electric power source and the energy storage device for supplying DC electric power to the energy storage device from said AC electric power source.

Abstract: In a hybrid electric motor vehicle, a power supply system for storing and supplying electrical power includes a motor-generator located onboard the vehicle, driveably connected to the vehicle wheels and producing AC electric power, an energy storage device for alternately storing and discharging electric power, an inverter coupled to the motor-generator and the energy storage device for converting alternating current produced by the motor-generator to direct current transmitted to the energy storage device, and for converting direct current stored in the energy storage device to alternating current transmitted to the motor-generator, a source of AC electric power located external to the vehicle, and a charger coupled to said electric power source and the energy storage device for supplying DC electric power to the energy storage device from said AC electric power source.

Abstract: A method for controlling the operation of a range extender of a hybrid electric vehicle in which a requested power signal P.sub.req is generated in response to the state-of-charge of the battery system being less than a predetermined intermediate value and the energy being consumed by the electric drive system being greater than the electric energy being delivered by the range extender. The requested power signal having a value approximately equal to the average power consumed by the electric drive system in a preceding time period. The method is responsive to the motor being in a energy regenerative state to decrease the power being generated by the range extender so that all the energy being generated by the motor is used to charge the battery. The method is also responsive to the engine temperature exceeding a predetermined temperature to reduce the power being delivered by the range extender.