Water Absorption Sensor of Generator Stator Bar Insulation using Cross Capacitance

크로스 커패시턴스를 이용한 발전기 고정자 권선 절연물 흡습 측정 센서

  • Received : 2011.08.18
  • Accepted : 2011.09.23
  • Published : 2011.10.01


The mechanical integrity of generator stator windings is one of the critical point because the electric power is generated and conducted to power system through these windings. To cool down the heat emitted from generator winding during its operation, a majority of generators use de-mineralized water characterized by high cooling efficiency. Contrary to such the excellent cooling efficiency, however, the damaged bar insulations attributed to the absorption of cooling water in the generator stator winding lead to highly time- and cost consuming efforts as well as to service deterioration due to unexpected forced outage of generator. It is described that the new design of water absorption sensor using cross capacitance for generator in power plant in order to increase the reliability of water absorption diagnostics for generator stator bar insulation.


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