Noise Analysis of Power System Frequency Estimated From Angle Difference of Discrete Fourier Transform Coefficient

Author

Jin Kwon Hwang ; Yilu Liu

Author_Institution

Dept. of Energy Eng., Woosuk Univ., Cheongju, South Korea

Volume

29

Issue

4

fYear

2014

fDate

Aug. 2014

Firstpage

1533

Lastpage

1541

Abstract

The frequency deviation of an electric power system is a reflection of its operating state. This frequency deviation can be estimated from angle variations of the discrete Fourier transform coefficient of the positive fundamental frequency. Most errors of the frequency estimate can arise from noise in the power system signal and the leakage effect of the negative fundamental frequency. This paper analyzes errors of the frequency estimates and the measured angle variations due to the noise. Their means and variances are derived theoretically with respect to signal-to-noise ratios and verified and analyzed through simulations.

Keywords

discrete Fourier transforms; frequency estimation; noise measurement; power systems; discrete Fourier transform coefficient; electric power system; leakage effect; negative fundamental frequency; noise analysis; positive fundamental frequency; power system frequency; power system signal; Discrete Fourier transforms; Frequency estimation; Harmonic analysis; Power system harmonics; Signal to noise ratio; Cramer-Rao lower bound (CRLB); Discrete Fourier transform (DFT); phase-angle measurement; power system frequency estimation; signal-to-noise ratio (SNR);

fLanguage

English

Journal_Title

Power Delivery, IEEE Transactions on

Publisher

ieee

ISSN

0885-8977

Type

jour

DOI

10.1109/TPWRD.2014.2315618

Filename

6807829