Abstract: A battery system includes a battery module, an active cell balancing circuit, and a battery controller. Each cell has diametrically-opposed positive and negative cell tabs. The circuit includes voltage sensors and, at each end of the battery module, first and second tiers of switches and an energy storage element. Each voltage sensor is located between a different pair of adjacent cells. The controller receives measured voltages from the sensors indicative of an electric potential between adjacent battery cells. Responsive to the measured voltages, the controller commands the first tier to selectively connect or disconnect designated pairs of cells to the corresponding second tier. The controller also commands the second tier to selectively connect or disconnect the designated cells to a corresponding energy storage element. This action shuttles energy between the designated pairs of battery cells to balance a state of charge.

Abstract: A battery system includes a battery module, an active cell balancing circuit, and a battery controller. Each cell has diametrically-opposed positive and negative cell tabs. The circuit includes voltage sensors and, at each end of the battery module, first and second tiers of switches and an energy storage element. Each voltage sensor is located between a different pair of adjacent cells. The controller receives measured voltages from the sensors indicative of an electric potential between adjacent battery cells. Responsive to the measured voltages, the controller commands the first tier to selectively connect or disconnect designated pairs of cells to the corresponding second tier. The controller also commands the second tier to selectively connect or disconnect the designated cells to a corresponding energy storage element. This action shuttles energy between the designated pairs of battery cells to balance a state of charge.

Abstract: A vehicle including an energy storage device and a powertrain system configured to effect regenerative braking is described. A method for controlling the vehicle includes determining an expected increase in a state of charge of the energy storage device achieved through opportunity charging by employing regenerative braking during an anticipated next trip of the vehicle. A preferred setpoint for the state of charge of the energy storage device is determined based upon the expected increase in the state of charge achieved through opportunity charging, and charging of the energy storage device is controlled during a remote charging event based upon the preferred setpoint for the state of charge of the energy storage device.

Abstract: A vehicle including an energy storage device and a powertrain system configured to effect regenerative braking is described. A method for controlling the vehicle includes determining an expected increase in a state of charge of the energy storage device achieved through opportunity charging by employing regenerative braking during an anticipated next trip of the vehicle. A preferred setpoint for the state of charge of the energy storage device is determined based upon the expected increase in the state of charge achieved through opportunity charging, and charging of the energy storage device is controlled during a remote charging event based upon the preferred setpoint for the state of charge of the energy storage device.

Abstract: A hybrid powertrain is provided that includes an engine operatively connected with an input member. The powertrain includes a transmission with first and second electric motor/generators, a differential gear set having multiple members, and selectively engageable torque-transmitting mechanisms. The input member, the output member, the engine and the motor/generators are selectively interconnected through the differential gear set by engagement of the torque-transmitting mechanisms in different combinations. The powertrain provides multiple operating modes between the input member and the output member, including an electric-only operating mode in which the engine is off and both electric motor/generators act as motors to provide torque at the output member.

Abstract: A hybrid powertrain is provided that includes an engine operatively connected with an input member. The powertrain includes a transmission with first and second electric motor/generators, a differential gear set having multiple members, and selectively engageable torque-transmitting mechanisms. The input member, the output member, the engine and the motor/generators are selectively interconnected through the differential gear set by engagement of the torque-transmitting mechanisms in different combinations. The powertrain provides multiple operating modes between the input member and the output member, including an electric-only operating mode in which the engine is off and both electric motor/generators act as motors to provide torque at the output member.

Abstract: A hybrid powertrain is provided that includes an engine operatively connected with an input member. The powertrain includes a transmission with first and second electric motor/generators, a differential gear set having multiple members, and selectively engageable torque-transmitting mechanisms. The input member, the output member, the engine and the motor/generators are selectively interconnected through the differential gear set by engagement of the torque-transmitting mechanisms in different combinations.

Abstract: A hybrid powertrain is provided that includes an engine operatively connected with an input member. The powertrain includes a transmission with first and second electric motor/generators, a differential gear set having multiple members, and selectively engageable torque-transmitting mechanisms. The input member, the output member, the engine and the motor/generators are selectively interconnected through the differential gear set by engagement of the torque-transmitting mechanisms in different combinations.

Abstract: A hybrid powertrain is provided that includes an engine operatively connected with an input member. The powertrain includes a transmission with first and second electric motor/generators, a differential gear set having multiple members, and selectively engagable torque-transmitting mechanisms. The input member, the output member, the engine and the motor/generators are selectively interconnected through the differential gear set by engagement of the torque-transmitting mechanisms in different combinations.

Abstract: A hybrid powertrain includes a control unit that regulates electric power interchange an energy storage device and a motor/generator for causing selective torque generation by the motor/generator and for controlling engagement of torque-transmitting mechanisms. The control unit is configured to place the torque-transmitting mechanism in slipping engagement to launch the vehicle and thereby decouple a fixed relationship between engine torque and motor/generator torque or between engine torque and torque at the output member. A method of operating a hybrid vehicle powertrain is also provided.

Abstract: A hybrid powertrain is provided that includes an engine operatively connected with an input member. The powertrain includes a transmission with first and second electric motor/generators, a differential gear set having multiple members, and selectively engagable torque-transmitting mechanisms. The input member, the output member, the engine and the motor/generators are selectively interconnected through the differential gear set by engagement of the torque-transmitting mechanisms in different combinations.

Abstract: A hybrid powertrain includes an electrically variable transmission and an internal combustion engine. The transmission is operable to provide a continuously variable mode of operation. The engine is capable of variable displacement in that at least half of the cylinders contained therein are deactivatable. Additionally the internal combustion engine operates with a late intake valve closing strategy to increase the peak efficiency of the internal combustion engine.

Abstract: A single range, electrically variable transmission (EVT) is provided with a lockup clutch that reduces motor power requirements. When applied, the lockup clutch allows engine torque to be transmitted directly to the output without the necessity of a motor/generator supplying reaction torque. With the lockup clutch applied, the transmission operates with zero electro-mechanical power flow at a fixed mechanical ratio, thus mitigating the power peak which occurs through the motor/generators. Input-split, output-split, and compound-split transmissions are disclosed. A method of operating an EVT with a lockup clutch is also provided.

Abstract: A method for controlling the cranking of an engine of a vehicle powertrain system having a rechargeable energy storage system that is adapted to provide electric power to an electric machine, wherein the system is adapted to exit from the engine crank state as a function of an output voltage of the energy storage system to the electric machine during the crank state, if the output voltage is less than a crank undervoltage threshold for a predetermined crank time. According to the method, the crank undervoltage threshold is a function of the number of failed start attempts, generally decreasing as a function of the number of failed start attempts. The predetermined crank time is a function of a magnitude of a difference between the output voltage and the crank undervoltage threshold.

Abstract: A hybrid powertrain incorporates an engine, two motor/generator mechanisms, and a planetary gearset. The planetary gearset has at least one torque-transmitting mechanism, which may be selectively energized to provide a brake on one of the motor/generators thereby reducing the electrical power generation within the hybrid transmission.

Abstract: A method and apparatus to control acceleration of a vehicle equipped with an electrically variable transmission and including a regenerative braking system, each are operably connected to a vehicle driveline. The method and apparatus include determining which one of a preselected shift selector position for the transmission is commanded, and determining operator demand for acceleration, using inputs from throttle pedal and brake pedal. Vehicle acceleration is measured, and magnitude of commanded torque transferred from the electrically variable transmission and the regenerative braking system to the vehicle driveline is controlled based upon the commanded preselected shift selector position, the operator demand for acceleration, and the measured vehicle acceleration.

Abstract: A two-mode, compound-split, electra-mechanical transmission utilizes an input member for receiving power from an engine, and an output member for delivering power from the transmission. First and second motor/generators are operatively connected to an energy storage device through a control for interchanging electrical power among the storage device, the first motor/generator and the second motor/generator. The transmission employs three planetary gear sets. Each planetary gear arrangement utilizes first, second and third gear members. Moreover, one gear member of the first or second planetary gear set is operatively connected to the input member, and one gear member of the third planetary gear set is selectively connected to ground. A lock-up clutch selectively locks two of the planetary gear sets in a 1:1 ratio.

Abstract: A motor vehicle has a multi-speed automatic transmission and a cruise control system. A method of shift control when the cruise control system is enabled infers from a plurality of factors based on cruise control error quantities the desirability of forcing a downshift to a lower speed ratio.

Abstract: A five-speed parallel-shaft clutch-to-clutch shifting automatic transmission has an hydraulically responsive clutch priority valve effective to exhaust fluid pressure from lower priority clutches upon undesirable simultaneous application two or more clutches. Two clutches associated with numerically nonadjacent gear ratios are supplied fluid pressure from a single solenoid controlled fluid valve vis-a-vis a two mutually exclusive state multiplex valve. The clutch priority valve is interposed between the solenoid controlled fluid valve and the multi-plex valve thereby rendering the two clutch states associated with the single solenoid valve indistinguishable by the clutch priority valve.

Abstract: Automotive internal combustion engine air/fuel ratio control accuracy improvement is provided through correction of engine cylinder volumetric efficiency to account for variation in engine intake air temperature away from volumetric efficiency calibration intake air temperature, and to account for heating of the intake air passing through engine intake air passages prior to entry to the engine cylinders. Change in air density and change in airflow dynamics occurring in engine intake air passages are accounted for in the volumetric efficiency correction so that engine control commands more accurately account for actual engine cylinder intake air mass.