Drive-line damping control for an electric vehicle

摘要

An electric motor vehicle (10) includes an electric motor (18) driving a step-down differential, axles (14l, 14r) and drive wheels (12r, 12l). An operator control (24) produces torque command signals, which are applied to a controller (20) to command application of electric power to the motor (18) in response to the torque commands, to achieve the desired torque. The low friction of the electric drive, in conjunction with the rotational compliance or imperfect stiffness of the axles (14l, 14r), may result in low-frequency surges or jerky motion, especially at low speeds. A damping arrangement includes a differencing circuit (210) coupled between the operator control (24) and the controller (20), for taking the difference between the operator-commanded torque and a damping torque signal. The damping torque signal is produced by differentiating the electric motor speed to produce a motor-acceleration representative signal.