Abstract: This novel silent operating mode for a hybrid electric vehicle (HEV) reduces noise and emissions compared to traditional HEV operating modes. It is a complementary series of software control functions that allows the vehicle to operate with reduced noise and emissions where specifically needed, while phasing-in engine power where allowed. The method utilizes an energy storage system budget associated with a modal quantity of energy allocated for the mode, and is adapted to automatically adjust the operation of the vehicle to accommodate deviations from the budgeted energy amount. The method which implements the mode also adjusts the vehicle operation in conjunction with changes in the parametric conditions of the ESS, including the selective use of the engine output power. In particular, the silent operating mode comprises a method of selecting an engine output power from a speed-based engine output power and a grade-based engine output power.

Abstract: A powertrain control selects engine operating points in accordance with power loss minimization controls. Power loss contributions come from a variety of sources including engine power losses. Engine power losses are determined in accordance with engine operating metrics such as power production per unit fuel consumption and power production per unit emission production. Engine power losses are combined in accordance with assigned weighting into a single engine power loss term for use in the power loss minimization control and operating point selection.

Abstract: A method and apparatus to control an electrically variable transmission, by dynamically controlling system main hydraulic clutch pressures, based upon required clutch capacity, as determined by output load of the transmission. Included is a method to regulate hydraulic clutch pressure in an electrically variable transmission equipped with at least one clutch. This comprises monitoring magnitude of slippage of the clutches and controlling hydraulic boost pressure based upon the magnitude of clutch slippage. Controlling hydraulic boost pressure based upon the magnitude of clutch slippage comprises monitoring operator inputs, determining a requested operator torque command, and determining a required main boost pressure. The main boost pressure is based upon the requested operator torque command, the monitored operator inputs, parameters of the EVT and clutches. Commanded main boost pressure is then determined based upon the determined required main boost pressure.

Abstract: A powertrain includes a diesel compression engine and an electric machine operatively coupled thereto and effective to rotate the engine during engine cranking. Cold engine cranking is accomplished in a staged manner including a first stage wherein the engine is cranked to a first speed below the resonant speed of the coupled engine and electric machine combination for a first duration and thereafter cranked to a second speed above the resonant speed for a second duration. Transition out of cranking at the first and second speeds is accomplished when relative combustion stability is demonstrated. Cranking at the first or second speed is aborted when excessive crank times or if low battery voltages are observed. A third stage is included wherein the engine is cranked to a third speed below the engine idle speed. Transition out of cranking at the third speed is accomplished when relative combustion stability is demonstrated, whereafter normal engine control takes over.

Abstract: Preferred operating points for a vehicle powertrain including an engine and a transmission are determined in accordance with a comprehensive operational mapping of input and output conditions and corresponding aggregate system losses corresponding to engine and transmission losses. In a hybrid transmission application, additional losses from motors and batteries are aggregated into the system losses and battery constraints are considered in determining preferred operating points. Preferred operating points are provided in one or more sets of minimized data for on-vehicle implementation.

Abstract: An preferred input torque for a hybrid powertrain is determined within a solution space of feasible input torques in accordance with a plurality of powertrain system constraints that results in a minimum overall powertrain system loss. Aggregate powertrain system losses are calculated at feasible input torques and a solution for the input torque corresponding to the minimum aggregate powertrain system loss is converged upon to determine the preferred input torque.

Abstract: A preferred input torque for a hybrid powertrain is determined within a solution space of feasible input torques in accordance with a plurality of powertrain system constraints that results in a minimum overall powertrain system loss. System power losses and battery utilization costs are calculated at feasible input torques and a solution for the input torque corresponding to the minimum total powertrain system loss is converged upon to determine the preferred input torque.

Abstract: Preferred operating points for a vehicle powertrain including an engine and a transmission are determined in accordance with a comprehensive operational mapping of input and output conditions and corresponding aggregate system losses corresponding to engine and transmission losses. In a hybrid transmission application, additional losses from motors and batteries are aggregated into the system losses and battery constraints are considered in determining preferred operating points. Preferred operating points are provided in one or more sets of minimized data for on-vehicle implementation.

Abstract: A multi-mode hybrid transmission has speed control provided via an open loop model derived as a function of preselected transmission accelerations and controlled and uncontrolled transmission torques. Motor torques are selected as the controlled torques and other preselected transmission torques are selected as the uncontrolled torques. The control also employs a closed loop control effort responsive to at least one preselected transmission speed error.

Abstract: This novel silent operating mode for a hybrid electric vehicle (HEV) reduces noise and emissions compared to traditional HEV operating modes. It is a complementary series of software control functions that allows the vehicle to operate with reduced noise and emissions where specifically needed, while phasing-in engine power where allowed. The method utilizes an energy storage system budget associated with a modal quantity of energy allocated for the mode, and is adapted to automatically adjust the operation of the vehicle to accommodate deviations from the budgeted energy amount. The mode also adjusts the vehicle operation in conjunction with changes in the parametric conditions of the ESS.

Abstract: Preferred operating points for a vehicle powertrain including an engine and a transmission are determined in accordance with a comprehensive operational mapping of input and output conditions and corresponding aggregate system losses corresponding to engine and transmission losses. In a hybrid transmission application, additional losses from motors and batteries are aggregated into the system losses and battery constraints are considered in determining preferred operating points.

Abstract: A method is disclosed for improving the performance of an energy storage system that incorporates a high density electrical energy storage device, such a battery or ultracapacitor. The method may be implemented in an energy storage system of a hybrid electric vehicle (HEV) as a computer control algorithm for controlling the discharge power limits of an energy storage device, such as a battery. The method allows the discharge power limits of the battery to be temporarily expanded under vehicle launch conditions where the power demands are high, thereby making additional stored energy available for use under such conditions by improving battery utilization and providing more consistent vehicle launch characteristics than would otherwise be available.

Abstract: A driver-initiated low traction control method limits the drive torque of a motor vehicle during operation on low traction road surfaces. The low traction control mode is initiated by actuation of a switch or by moving a transmission range selector to a Low range while the vehicle is substantially stopped, and terminated by further actuation of the switch or by returning the range selector back to the Drive setting. The low traction control mode limits the engine torque as required to limit the drive wheel torque and its rate of change, so long as cruise control is inactive, the accelerator pedal setting is less than a reference level, and the transmission is operating in a gear other than its top gear. When the low traction control mode is terminated, the engine torque limits are progressively removed in a way that does not produce perceptible acceleration or deceleration of the vehicle.

Abstract: This novel silent operating mode for a hybrid electric vehicle (HEV) reduces noise and emissions compared to traditional HEV operating modes. It is a complementary series of software control functions that allows the vehicle to operate with reduced noise and emissions where specifically needed, while phasing-in engine power where allowed. The method utilizes an energy storage system budget associated with a modal quantity of energy allocated for the mode, and is adapted to automatically adjust the operation of the vehicle to accommodate deviations from the budgeted energy amount. The mode also adjusts the vehicle operation in conjunction with changes in the parametric conditions of the ESS.

Abstract: A powertrain having a controller for limiting the torque and power inputs to a transmission as determined by operating parameters and design features of the transmission. These parameters and design features include torque limits for various components in the transmission, torque ratio of the torque converter, the design K factor of the torque converter, gear ratios of the transmission, operating condition of the torque converter clutch, and input power limits for the transmission. A programmable digital computer includes a subroutine that evaluates and establishes torque limits and input speed limits from the design features and operating parameter. The controller sets the limits for each transmission ratio including reverse such that a family of transmission can be coupled to a single engine design without overpowering the transmission should the engine be capable of greater output power than the transmission can accept.

Abstract: A powertrain having a controller for limiting the torque and power inputs to a transmission as determined by operating parameters and design features of the transmission. These parameters and design features include torque limits for various components in the transmission, torque ratio of the torque converter, the design K factor of the torque converter, gear ratios of the transmission, operating condition of the torque converter clutch, and input power limits for the transmission. A programmable digital computer includes a subroutine that evaluates and establishes torque limits and input speed limits from the design features and operating parameter. The controller sets the limits for each transmission ratio including reverse such that a family of transmission can be coupled to a single engine design without overpowering the transmission should the engine be capable of greater output power than the transmission can accept.

Abstract: An improved engine and transmission control method for coordinated control of closed-throttle transmission shifting, wherein the transmission control provides engine speed and torque rate limits to the engine control based on the shift parameters. The speed and/or torque rate limits come into play if the driver suddenly increases the engine throttle setting. Additionally, in driver requested garage shifts, initiation of the shift is prevented until the engine speed is within the speed limit. Preferably, the engine speed limit is set a calibrated amount above the computed input synchronization speed (SYNC). Alternately, the engine speed limit may be set to a value that limits the energy dissipated in the on-coming clutch to a predetermined value. With either approach, the engine speed and torque limits modify the engine control only to the extent necessary to preserve high shift quality while limiting the on-coming clutch energy dissipation to a safe level.

Abstract: An improved control for an automatic transmission power-on downshift, wherein a dynamic model of the transmission is used to schedule the on-coming and off-going clutch pressures based on the transmission input torque and a desired trajectory of the input shaft during the shift. The shift is initiated with the off-going clutch by using the dynamic model achieve consistent initiation of clutch slippage, and to conform the input speed to the desired trajectory. When the input speed nears a synchronization speed for the target speed ratio, the dynamic model is used to engage the on-coming clutch at a rate based on the input torque while maintaining the input speed in synchronism with the target speed ratio. As a result, the control responds appropriately to dynamic changes in input torque, the input speed more accurately tracks the desired trajectory, and the shifts are completed at or near synchronism.

Abstract: An improved automatic shift transmission control method establishes an initial methodology for sharing adaptive corrections among shift parameters stored for related types of shifts, and subsequently modifies the initial methodology as the adapted parameters converge on respective optimum values. Individual shift types are initially categorized to indicate the degree of cross-adaptive correction, and when shift parameter convergence occurs, the shift types are re-categorized, thereby modifying the initial cross-adaptive methodology to restrict further cross-adaptive correction. A given shift type is automatically reset to an initial or prior categorization to permit less restricted cross-adaptive correction if reset conditions are met. In this way, the methodology for sharing adaptive corrections automatically evolves to suit individual transmission operating characteristics and conditions, and effectively prevents degradation of a shift due to sharing of adaptive corrections developed for a related shift.

Abstract: An improved power-on downshift control wherein the off-going clutch pressure is controlled to achieve a desired trajectory of the input shaft during the shift, and wherein the desired trajectory is scheduled to optimize shift smoothness under ordinary conditions and shift responsiveness under high driver demand conditions. A driver demand indication such as engine throttle position is monitored, and when its rate of increase exceeds a reference rate, a high rate condition is identified and the current demand indication is stored for future reference. A high demand indication or flag is set or cleared based on the high rate indication and a comparison of the driver demand indication to the stored value.