A Protection Algorithm for DC Railway Systems Using Estimation of Time Constant Based on Fourier Transform

Fourier 변환 기반 시정수 추정 알고리즘을 이용한 직류 급전계통 보호 알고리즘

  • 권영진 (명지대학교 차세대전력기술연구센터) ;
  • 최동민 (명지대학교 차세대전력기술연구센터) ;
  • 강상희 (명지대학교 차세대전력기술연구센터) ;
  • 한문섭 (철도기술연구원) ;
  • 이재경 ((주)젤파워)
  • Published : 2004.11.12

Abstract

A DC railway system has low feeder voltage, The remote fault current can be smaller than the current of load starting. So it is important to discriminate between the small fault current and the load starting current. The load starting current increases step by step but the fault current increases all at once. As for the load starting current, the time constant of load current at each step is much smaller than that of the fault current. To detect faults in DC railway systems, an algorithm using the time constant calculated by the method of least squares was presented. But, It have a weakness about harmonic to calculate time constant. So in this paper, new protection algorithm for DC railway systems using estimation of time constant based on fourier transform was presented.

Keywords