Nonlinear analysis and application of servo control system based on relay feedback

Abstract

In this paper, a PID controller tuning technology under different loads and velocities based on relay feedback for motor servo systems is proposed. Furthermore, the study on the relationship between relay parameters and plants' identification processes and results is novelly explored in depth. Through the theoretical analysis and experimental verification on the control loops of motor servo systems, we found that the major reason for the influence on relay feedback identification results is the nonlinear factors such as nonlinear friction in control loops. According to the analysis, the advices for optimizing the selection of relay parameters are given. Finally, a series of experiments on the general XY motion table and Zero-friction high precision air-cushion XY motion table have been conducted to prove the high performance of the proposed method. These experiments also validated the inference that the nonlinear factors have impacts on the results and processes of relay feedback identification. © 2009 Springer-Verlag Berlin Heidelberg.