Iterative Feedback Tuning of Cascade Control of Two-Inertia System

The cascade control of the servo system has an inner control loop and an outer control loop to achieve high-performance robust control. However, additional efforts are required because the inner and outer controllers need to be sequentially tuned. To address this problem, this letter proposes a novel iterative feedback tuning method for cascade control. The proposed method adopts a cost function that is designed taking into consideration the cascade control structure and utilizes it for the IFT algorithm to simultaneously tune the inner and outer control loops. The effectiveness of the proposed method is verified by experiments using a two-inertia system which is subject to vibration. The experimental results verify that the proposed IFT can optimize the cascade controller under various plant conditions.