A practical approach to the time-derivative estimation problem based on PI-SOGI filters bank

In this paper, a new approach, namely PI-SOGI, is proposed for the time-derivative estimation of an unknown signal. The approach described herein uses a Proportional-Integral regulator (PI) to control an orthogonal signals generator based on Second-Order Generalized Integrator (SOGI) in order to track the reference signal obtaining its first derivative. A PI-SOGI filters bank can be used to estimate derivatives of order greater than one. A theoretical analysis on the characteristics of the tracking error is provided. The effectiveness of the proposed method is demonstrated through simulated experiments and comparisons with existing ones.