Method for automatic traction control in a hybrid electric vehicle

摘要

A method for providing traction control in vehicle powertrain systems is particularly adapted for traction control in a powertrain system of a hybrid electric vehicle comprising an internal combustion engine, an electric machine and a transmission that is operatively coupled to the electric machine and the engine and adapted to provide a transmission torque output in response to a transmission torque input received as a torque output from either or both of the engine and the electric machine. The method is adapted to utilize conventional traction control and engine control hardware, software and communication standards to implement traction control. In one embodiment of the invention, a conventional traction controller is used to detect a wheel spin condition and provide a plurality of first output torque command messages in response thereto. The plurality of first output torque command messages are used to obtain a torque reduction which is applied to a reference output torque to obtain a corresponding plurality of traction control output torque commands for the powertrain system during the wheel spin condition. A rate limit may also be applied to control the rate of change between successive ones of the traction control output torque commands in order to reduce the possibility of extension of the wheel spin condition, or recurrence of another wheel spin condition. Each traction control output torque command may be used to determine an associated traction control engine torque output command and traction control electric machine torque output command.