An Enhanced Algorithm for Frequency Estimation in Power Systems

Operating frequency is one of the most important parameters in power system. This paper proposes a new algorithm for power system frequency estimation. The algorithm is based on the Hilbert-transform phase-locked loops (HTPLL) and the complex least mean square (CLMS) method. The three-phase voltage data is input to the HTPLLs to obtain an approximate frequency estimation, and a complex voltage vector is formed using an alpha beta-transform. By then, combining the complex voltage vector and the approximate estimate, the CLMS algorithm provides a refined frequency estimation. Simulation results of the proposed algorithm are presented and the performance of the algorithm is compared to other frequency tracking techniques.