Prognostics for Stator Windings of Water-Cooled Generator Against Water Absorption

수냉식 발전기 고정자 권선의 흡습 건전성 예지

  • Jang, Beom Chan (Dept. of Mechanical and Aerospace Engineering, Seoul Nat'l Univ.) ;
  • Youn, Byeng D. (Dept. of Mechanical and Aerospace Engineering, Seoul Nat'l Univ.) ;
  • Kim, Hee Soo (Korea Electric Power Research Institute) ;
  • Bae, Yong Chae (Korea Electric Power Research Institute)
  • 장범찬 (서울대학교 기계항공공학부) ;
  • 윤병동 (서울대학교 기계항공공학부) ;
  • 김희수 (한국전력 전력연구원) ;
  • 배용채 (한국전력 전력연구원)
  • Received : 2014.11.21
  • Accepted : 2015.04.07
  • Published : 2015.06.01


In this study, we develop a prognostic method of assessing the stator windings of power generators against water absorption through statistical data analysis and degradation modeling. The 42 windings of the generator are divided into two groups: the absorption and normal groups. A degradation model of a winding is constructed using Fick's second law to predict the level of absorption. By analyzing data from the normal group, we can determine the distribution of the data of normal windings. The health index of a winding is estimated using the directional Mahalanobis distance (DMD) method. Finally, the probability distributions of the failure time of the windings are determined.


Prognostics;Power Generator;Water Absorption


Supported by : 한국에너지기술평가원(KETEP)


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