Electrical Degradation of Stator Bars for Large Turbine Generator after 1000 Thermal Cycles

대형 터빈 발전기용 고정자 권선의 1000 thermal cycle 후 전기적 특성 변화

  • Kang, Myung-Guk (Generator Design Team, Doosan Heavy Industries & Construction Co., Ltd.) ;
  • Kim, Tae-Hee (Fuel Cell Development Team, Doosan Heavy Industries & Construction Co., Ltd.) ;
  • Lee, Jai-Kwun (Generator Design Team, Doosan Heavy Industries & Construction Co., Ltd.)
  • 강명국 (두산중공업(주) 터빈발전기BG 발전기설계팀) ;
  • 김태희 (두산중공업(주) 기술연구원 연료전지개발팀) ;
  • 이재권 (두산중공업(주) 터빈발전기BG 발전기설계팀)
  • Published : 2007.07.18

Abstract

Thermal and mechanical stresses, caused by repetitive start and stop and load fluctuation during long time operation, on winding stator bars are one of the main causes for electrical degradation of insulating materials. To understand the degradation process, we manufactured bar specimens with the same processes that make generator winding stator bars and the specimens were subjected to various degrees of thermal cycling. Measurements of the insulation properties, such as dissipation factor, tip-up and partial discharge, for un-aged specimens and for specimens aged by thermal cycling at 50, 100, 250, 500 and 1000 thermal cycles were performed. Finally all specimens were tested to obtain electrical breakdown voltages. In this paper we present the data and electrical degradation analysis results obtained during this program.

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