Analysis and Development of a Disturbance Compensation Approach for Performance Improvement in Speed Control

In high-precision motion control applications, elimination of adverse effects caused by friction and disturbance is a key issue. In particular, when the system undergoes low-speed or reversal motions, the inherent friction force and/or external disturbances may degrade motion accuracy. Therefore, in order to achieve satisfactory motion accuracy, it is necessary to suppress the adverse effects due to friction and/or dis-turbance. In order to deal with the aforementioned problem often encountered in motion control applica-tions, this paper develops a disturbance compensation approach, which is called Nominal-plant-based Disturbance Compensator (NDC). The advantage of the proposed NDC is that it not only can accurately estimate external disturbance/load torque, but also has superior ability in external disturbance suppression and measurement noise reduction. To address the properties of the proposed approach, theoretical analy-sis of the transfer functions for different schemes are derived first. Subsequently, several experiments on load torque estimation, speed control, and contour are conducted to evaluate the performance of the proposed approach. Experimental results demonstrate the effec-tiveness of the proposed approach. © 2021, Chinese Mechanical Engineering Society. All right reserved.