Caterpillar Inc.
Control system for controlling operation of a drive motor

Abstract:

A control system for controlling operation of a drive motor includes an input device for providing a command signal that is indicative of a desired speed and direction of rotation of the drive motor. A sensor is associated with the drive motor and adapted to provide a sensor signal indicative of current rotational speed of the drive motor. A controller receives the command signal, and determine whether the command signal is indicative of a desired zero speed to be associated with the drive motor. The controller also receives the sensor signal, and determine whether the current rotational speed of the drive motor is within a pre-defined range of difference from the desired zero speed. The controller then generates a de-rated torque command signal having a reduced gain factor, and reduce the current rotational speed of the drive motor based on the de-rated torque command signal.