A Finite-Time Observer-Based Identification of Sinusoidal Signal With Unknown Frequency.

In this article, we studied the parameters identification problem for the single sinusoidal signal based on the finite-time observer technique. After representing the sinusoidal signal with known frequency as a second-order time-invariant system, a finite-time observer-based estimation strategy is designed based on the homogeneous system theory to obtain unknown amplitude and phase angle. When the signal frequency is unknown, the original signal will be constructed into a third-order nonlinear system, which is challenging to design the corresponding state estimator. Based on the Lyapunov analysis method and adding a power integrator technique, a finite-time estimation scheme is developed and analyzed strictly. Finally, for a single-phase grid signal, some experimental results are provided to illustrate the efficacy of the proposed method. [ABSTRACT FROM AUTHOR]