Variable-Performance Nonlinear Feedback Filter Based on Dynamic Surface Stabilization Approach

The proposed surface stabilization technique based filter feedbacks the filtering error with its nonlinear variable gain algorithm in order to recover the source signal information rejecting the high-frequency component (e.g., low-pass filtering), thereby guaranteeing closed-loop stability. Thus, resultant implementation is possible without signal dynamics information. The result provides two contributions: first, the improvement of the transient filtering performance through the closed-form feedback gain magnification mechanism and second, the recovery of the exponential filtering performance due to the surface stabilization mechanism, including the exponential convergent disturbance estimator originated from the nonlinear disturbance observer. The experimental results verify the effectiveness of the proposed technique, which improves the 500-W three-phase motor control performance.