Patent ID: 8066615
Filing Date: 2011-11-29
Classification: B60K,B60L,B60W,F16H,Y02T,Y10S,Y10T

Abstract:
1. Method for operating a powertrain including an electro-mechanical transmission mechanically-operatively coupled to an internal combustion engine at a transmission input and a plurality of electric machines for mechanical power flow to a transmission output through selective actuation of a plurality of torque-transfer devices, said electric machines electrically-operatively coupled to an energy storage system for electric power flow therebetween, said electro-mechanical transmission selectively operative in one of a plurality of continuously variable and fixed gear operating range states, the method comprising: commanding operation of the electro-mechanical transmission in one of the continuously variable operating range states; commanding operation of the engine in a closed-loop speed control mode which always includes operation of the engine; monitoring rotational speed of the transmission input, each of the plurality of electric machines, and the transmission output, and; monitoring operator inputs comprising an operator torque request and an operator braking request; during operation of the engine in the closed-loop speed control mode, detecting presence of a potential mismatch between the commanded operating range state comprising said one of the continuously variable operating range states and an actual operating range state comprising one of the fixed gear operating range states based upon a determined deceleration in the transmission output due to the presence of the potential mismatch; and, modifying operation of the powertrain when a change in the rotational speed of the transmission output exceeds a threshold absent a corresponding change in the monitored operator inputs.