A Precise Calculation of Power System Frequency and Phasor

A series of precise digital algorithms based on Discrete Fourier Transforms (DFT) to calculate the frequency and phasor in real-time are proposed. These algorithms that we called the Smart Discrete Fourier Transforms (SDFT) family not only keep all of the advantages of DFT but also smartly take frequency deviation, and harmonics into consideration. These make the SDFT family more accurate than the other methods. Besides, SDFT family is recursive and very easy to implement, so it is very suitable for use in real-time. We provide the simulation results compared with conventional DFT method and second-order Prony method to validate the claimed benefits of SDFT. Index Terms--Discrete Fourier Transforms (DFT), Frequency estimation, phasor measurement.