High‐speed positioning method for servomotor considering friction load torque

When the position error becomes small, in a conventional positioning system, its motor cannot obtain sufficient deceleration torque. Hence, the position response becomes slow. There is another positioning system that is to design the position reference using a trapezoidal speed reference. When the load torque and the final goal position are known, this positioning system has a fine response. However, if the load torque and the final goal vary, its position response cannot have the desired response. In order to overcome these problems, this paper proposes a new high‐speed positioning system of AC servomotor considering both an unknown friction torque and a windup phenomenon. The proposed system always uses the maximum acceleration, deceleration torque and the maximum speed. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 157(4): 66– 74, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20173