A design method of active disturbance rejection controller for linear motor servo systems

Active disturbance rejection control (ADRC), which can overcome the influence of unmodeled dynamics and unknown disturbance, does not need precise model for its design. However, ADRC has several parameters, which make it difficult to config. To solve the problem above, this paper proposes a design method of ADRC for linear motor servo system. The relation between feedback gain and phase margin is analyzes, and then the rule of tuning feedback gain is obtained. In the design method of this paper, some parameters of ADRC is estimated using experimental data at first, then tracking differentiator and expanded states observer are designed according to the parameters of the linear motor, and at last the feedback gain is tuned following some tuning rules. The experimental results show that this method not only has good control performance, but also greatly improve the efficiency of tuning parameters.