Patent ID: 9132825
Filing Date: 2015-09-15
Classification: B60W,B60Y,F16H

Abstract:
1. A method of preventing over-shifting in an electric vehicle having a multi-gear transmission and an electric motor operable in a drive mode and a regenerative braking mode, the method comprising the steps of: (a) predicting the speed of the electric motor resulting from downshifting from a current gear being used to a next lower gear based on a current speed of the electric vehicle, a current speed of the electric motor, and a gear ratio of the next lower gear; (b) determining if the speed of the electric motor predicted in (a) will cause an overvoltage condition from regenerative braking or an overspin condition in the electric motor; (c) preventing downshifting to the next lower gear when it is determined that the downshifting will cause an overvoltage condition or an overspin condition in the electric motor; and (d) repeating steps (a), (b), and (c) a plurality of times.