摘要:
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.
摘要:
A hybrid vehicle includes a powertrain having a retarded diesel engine, an electric machine and energy storage system. The engine and motor are operatively coupled through one or more planetary gearsets and selective coupling paths in accordance with application and release of various torque transfer devices to a drivetrain via an output. Regenerative and retarded engine braking are coordinated to provide priority to energy return to an energy storage system in accordance with predetermined power flow limits.
摘要:
A method of operating a vehicle powertrain system comprising an electric motor and transmission where the electric motor is operably and selectively coupled to the transmission and adapted to provide an output torque contribution thereto, and the electric motor has a predetermined maximum motor output torque and a predetermined minimum motor output torque which are used to determine a range of permissible control points for at least one transmission control parameter. The method includes establishing a motor torque reserve by performing at least one of decreasing the predetermined maximum motor output torque to a maximum reserved motor output torque and increasing the minimum motor output torque to a minimum reserved motor output torque, wherein the maximum reserved motor output torque and the minimum reserved motor output torque are used in place of the predetermined maximum motor output torque and the predetermined minimum motor output torque, respectively, to determine the range of permissible control points for the at least one transmission control parameter. The motor torque reserve may include a static motor torque reserve, a dynamic motor torque reserve, or a combination of both static and dynamic torque reserves. The dynamic torque reserve may include a predictive dynamic reserve, a reactive dynamic reserve, or a combination of a predictive reserve and a reactive reserve or reserves.
摘要:
A method for determining output torque limits of a powertrain including an electrically variable transmission relies upon a model of the electrically variable transmission. Transmission operating space is defined by electric machine torque constraints, engine torque constraints and battery power constraints. Output torque limits are determined at the limits of the transmission operating space.
摘要:
A hybrid vehicle includes a powertrain having a retarded diesel engine, an electric machine and energy storage system. The engine and motor are operatively coupled through one or more planetary gearsets and selective coupling paths in accordance with application and release of various torque transfer devices to a drivetrain via an output. Regenerative and retarded engine braking are coordinated to provide priority to energy return to an energy storage system in accordance with predetermined power flow limits. Power flow in excess of the limits are handled by increased engine retard braking contributions via engine speed increases.
摘要:
A method of operating a vehicle powertrain system comprising an electric motor and transmission where the electric motor is operably and selectively coupled to the transmission and adapted to provide an output torque contribution thereto, and the electric motor has a predetermined maximum motor output torque and a predetermined minimum motor output torque which are used to determine a range of permissible control points for at least one transmission control parameter. The method includes establishing a motor torque reserve by performing at least one of decreasing the predetermined maximum motor output torque to a maximum reserved motor output torque and increasing the minimum motor output torque to a minimum reserved motor output torque, wherein the maximum reserved motor output torque and the minimum reserved motor output torque are used in place of the predetermined maximum motor output torque and the predetermined minimum motor output torque, respectively, to determine the range of permissible control points for the at least one transmission control parameter.
摘要:
A method for determining output torque limits of a powertrain including an electrically variable transmission relies upon a model of the electrically variable transmission. Transmission operating space is defined by combined electric machine torque constraints and engine torque constraints. Output torque limits are determined at the limits of the transmission operating space.
摘要:
A condition of impaired speed and torque control of a parallel electrically variable transmission due to factors beyond nominal modeling and estimation errors is diagnosed under low speed operation. The transmission includes at least one electric machine and a motor torque controller for regulating the transmission input speed and output torque. The motor torque controller includes an open-loop control path based on predetermined torques and accelerations and a closed loop control path based on input speed error. The presence of a larger than expected closed-loop correction magnitude, combined with low output speed and one or more other conditions is used to diagnose a condition of potential torque error, in which case the transmission control is altered to prevent unwanted operation.
摘要:
The normal control of an electrically-activated hydraulic valve armature is overridden to automatically and periodically open the armature for flushing out debris that has accumulated between the armature and a seat that the armature is designed to engage. The valve develops fluid pressure for maintaining engagement of a motor vehicle transmission clutch, and when excessive slippage of the clutch is detected, the armature is forced into engagement with the seat until the slippage is reduced or a predetermined period of time has elapsed, after which the armature is temporarily positioned away from the seat to provide full flow of hydraulic fluid across the seat to flush out debris that prevents the armature from engaging the seat. During Neutral operation of the transmission, the armature is continuously positioned away from the seat, and during low torque conditions the armature is temporarily positioned away from the seat.
摘要:
A vehicular powertrain includes operatively coupled engine, electrically variable transmission and driveline. During normal operation when all motors are operating as expected, the engine is operated in a torque control mode in accordance with a torque command provided by a system controller to an engine controller and engine speed is controlled by the motors. During operation when all motors are not operating as expected, the engine is operated in a speed control mode in accordance with a speed command provided by the system controller to the engine controller and engine load torque is controlled by the operative motors.