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.