An Estimation Algorithm for Oscillation Frequency under Power Oscillations

With the continuous introduction and development of power electronic devices in the power grid, the characteristics of power system oscillation are becoming more complicated. The existing phasor measurement technology is difficult to accurately estimate the parameters of the power oscillation. In order to solve the problem of measuring the oscillation frequency when the power oscillation occurs in the power system, this paper proposes an algorithm for measuring the oscillation frequency based on the Taylor-least-squares method (TLSM). Firstly, the oscillation signal model including amplitude and phase oscillation parameters is established by using the Taylor series expansion. Secondly, the expressions of phase and amplitude oscillation frequency are derivated in detail. Finally, the estimation equation is constructed based on TLSM, and the oscillation frequency in the oscillation model is solved. The simulation results show that the proposed method can accurately measure the oscillation frequency of phase and amplitude oscillations, and the measurement error can be controlled below 10-² Hz in most periods.