The Transactions of The Korean Institute of Electrical Engineers (전기학회논문지)

The Korean Institute of Electrical Engineers (대한전기학회)
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Fourier Transform-Based Phasor Estimation Method Eliminating the Effect of the Exponentially Decaying DC offsets

지수 감쇄하는 DC 옵셋 영향을 제거한 푸리에 변환 기반 페이져 연산 기법 기법

  • 이동규 (명지대 차세대전력기술연구센터) ;
  • 김철훈 (명지대 차세대전력기술연구센터) ;
  • 강상희 (명지대 차세대전력기술연구센터)
  • Published : 2008.09.01
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Abstract

This paper proposes a new Fourier transform-based phasor estimation method to eliminate the adverse influence of the exponentially decaying dc offsets when Discrete Fourier Transform (DFT) is used to calculate the phasor of the fundamental frequency component in a relaying signal. By subtracting the result of odd-sample-set DFT from the result of even-sample-set DFT, the information of dc offsets can be obtained. Two dc offsets in a relaying signal are treated as one dc offset which is piecewise approximated in one cycle data window. The effect of the dc offsets can be eliminated by the approximated dc offset. The performance of the proposed algorithm is evaluated by using computer-simulated signals and EMTP-generated signals. The algorithm is also tested on a hardware board with TMS320C32 microprocessor. The evaluation results indicate that the proposed algorithm has the stable and accurate eliminating performance even if the input signal contains two decaying dc components having different time constants.

Keywords

References

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