A Precise Calculation of Power System Frequency

Author

Yang, J. Z. ; Liu, C. W.

Author_Institution

National Taiwan University, Taipei, Taiwan

Volume

21

Issue

4

fYear

2001

fDate

4/1/2001 12:00:00 AM

Firstpage

71

Lastpage

71

Abstract

A precise digital algorithm based on discrete Fourier transforms (DFT) to estimate the frequency of a sinusoid with harmonics in real time is proposed. This algorithm, which we call the smart discrete Fourier transform (SDFT), smartly avoids the errors that arise when frequency deviates from the nominal frequency, and keeps all the advantages of the DFT (e.g., immune to harmonics and the recursive computing can be used in SDFT). These make the SDFT more accurate than conventional DFT-based techniques. In addition, this method is recursive and easy to implement, so it is suitable for use in real time. We provide the simulation results compared with a conventional DFT method and second-order Prony method to validate the claimed benefits of SDFT.

Keywords

Digital relays; Discrete Fourier transforms; Frequency; Power engineering; Power system harmonics; Power system management; Power system protection; Power system relaying; Power systems; Protective relaying; Discrete Fourier transforms (DFT); frequency estimation; phasor measurement;

fLanguage

English

Journal_Title

Power Engineering Review, IEEE

Publisher

ieee

ISSN

0272-1724

Type

jour

DOI

10.1109/MPER.2001.4311328

Filename

4311328