Frequency and Offset Online Estimation of Sinusoidal Signals Based on High‐Order Nonlinear Continuous Differentiator

Real‐time parameter identification of sinusoidal signals is an essential research topic due to its broad utilization in both theoretical studies and engineering practice. A tracking differentiator based online estimation framework has been proposed to simultaneously identify frequencies and offset of given multi‐sinusoidal signal. Tracking differentiator is exploited in presented framework to track the time derivatives of measurements which are then utilized to estimate the frequencies and offset. We introduce a tracking differentiator called high‐order nonlinear continuous differentiator into the framework, giving birth to a new estimation algorithm. Comparative experiments on both single and two sinusoidal signal are simulated, indicating the superiority of proposed method on both convergent speed and estimation accuracy.