Patent ID: 8298118
Filing Date: 2012-10-30
Classification: B60L,B60W,F16H,Y02T,Y10T

Abstract:
1. A method for operating a motor vehicle hybrid powertrain having an engine, a motor-generator and a multi-speed automatically-shiftable transmission, and for reducing an output torque disturbance in the transmission during a gear shift, the engine and the motor-generator each operatively connected to the transmission to provide a supply of torque for driving a vehicle, the method comprising: modulating the supply of torque from the motor-generator to the transmission during the gear shift, sufficiently such that the output torque disturbance during the gear shift is minimized; initiating the gear shift from an off-going gear into an on-coming gear via an off-going clutch and an on-coming clutch; determining a desired transmission input speed corresponding to transmission output speed, and a magnitude of output torque in the on-coming gear; commencing engagement of the on-coming clutch; determining a magnitude of torque transmitted by the on-coming clutch; continuing the engagement of the on-coming clutch to achieve the determined magnitude of output torque in the on-coming gear; determining whether a magnitude of torque transmitted by the off-going clutch is below a predetermined torque threshold; releasing the off-going clutch if the off-going clutch torque is below the predetermined torque threshold; determining whether a slip speed of the on-coming clutch is below a predetermined slip speed threshold value; and completing the engagement of the on-coming clutch to achieve the desired transmission input speed and the determined magnitude of output torque in the on-coming gear if the slip speed of the on-coming clutch is below the predetermined slip speed threshold value.