Vibration suppression control of two-inertia system without using drive-side information by applying high-resolution encoder

The developments in position control methods have enabled us to obtain a rapid response or high control bandwidth for improving control performance. However, there is an emerging problem in which a control system with a high control bandwidth may excite mechanical vibration, which deteriorates control performance. This is the case especially in a mechanism that has a flexible joint between the motor and the load, such as the feeding tables of machine tools, the arms of industrial robots, and rolling mills. Therefore, there is a strong demand for vibration suppression control with a high control bandwidth while maintaining productivity. For high-precision control of a two-inertia system, the position information of both the motor side and load side is usually required to obtain a high control bandwidth. In order to reduce the implementation cost and space, a novel control method, which employs the load-side information only, is proposed using a high-resolution encoder. Simulation and experimental results demonstrate that the proposed method is implementable and exhibits good control performance. © 2015 The Institute of Electrical Engineers of Japan.