A Three-Winding Transformer Protective Relaying Algorithm Based on Flux Linkages Ratio

쇄교자속비를 이용한 3권선 변압기 보호 알고리즘

  • Kang, Y.C. (Chonbuk National University, NPT Center) ;
  • Lee, B.E. (Chonbuk National University, NPT Center) ;
  • Jin, E.S. (Chonbuk National University, NPT Center) ;
  • Won, S.H. (Chonbuk National University, NPT Center) ;
  • Lim, U.J. (Chonbuk National University, NPT Center)
  • 강용철 (전북대학교 전자정보 공학부, 차세대전력기술연구센터) ;
  • 이병은 (전북대학교 전자정보 공학부, 차세대전력기술연구센터) ;
  • 김은숙 (전북대학교 전자정보 공학부, 차세대전력기술연구센터) ;
  • 원성호 (전북대학교 전자정보 공학부, 차세대전력기술연구센터) ;
  • 임의재 (전북대학교 전자정보 공학부, 차세대전력기술연구센터)
  • Published : 2003.11.13

Abstract

This paper proposes a tree-winding transformer protective relaying algorithm based on the ratio of increment of flux linkages (RIFL). The RIFL of the two windings is equal to the turns ratio for all operating conditions except an internal faults. For a single-phase transformer and three-phase transformer containing the wye-connected windings, the increments of flux linkages are calculated. for a three-phase transformer containing the delta-connected windings, the difference of the increments of flux linkages between the two phases are calculated using the line currents, because the winding currents are practically unavailable. Their ratios are compared with the turns ratio. The results of various tests show that the algorithm successfully discriminates internal faults from normal operation conditions such as magnetic inrush, overexcitation and external faults. The algorithm can not only detect internal winding faults, but reduce the operating time of a relay.

Keywords