Journal of the Institute of Electronics Engineers of Korea SP (대한전자공학회논문지SP)

The Institute of Electronics and Information Engineers (대한전자공학회)
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Performance degradation caused by coefficient approximation in Sliding-DFT based phasor measurement

순환 DFT 기반의 동기 위상 측정에 있어서 계수 근사에 따른 성능 열화 분석

  • Kim, Chong-Yun (School of Electrical Engineering, Chung-Ang University/NPTC) ;
  • Chang, Tae-Gyu (School of Electrical Engineering, Chung-Ang University/NPTC)
  • 김종윤 (中央大學敎 電子電氣工學部) ;
  • 장태규 (中央大學敎 電子電氣工學部)
  • Published : 2002.07.01
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Abstract

This paper presents an analysis of the performance degradation of coefficient approximation and frequency deviation in phase measurement algorithm based on Sliding-DFT. The analytic derivation is based on the statistics of the error dynamic equation that describes the error propagation of the recursion. The analysis result is intended to obtain a closed-form equation of error variance in terms of the number of bits used in coefficient approximation, the length of the DFT data block, and noise. It is verified with data obtained from the computer simulations.

본 논문에서는 순환 DFT 기반의 위상 측정 알고리즘을 구현함에 있어서 계수 근사 및 주파수 변이에 따른 성능 열화를 해석하였다. 오차의 영향을 해석하기 위해서 근사 순환 DFT식을 이용하여 오차 방정식(error dynamics)을 정의하고 이의 통계적 특성을 이용하여 오차의 특성을 분석한다. 오차 전력은 오차파급의 주요 영향 요소인 근사 bit수, DFT 구간 길이와 잡음에 관한 closed-form으로 유도되어 진다. 해석적으로 유도한 식과 시뮬레이션 실험을 통해 얻을 결과를 비교하여 타당성을 확인하였다.

Keywords

References

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