Title |
On-line partial discharge measurement techniques of hydro-generator windings |
Authors |
황동하 ; 김진봉 ; 김용주 ; 박명수 ; 김택수 |
Keywords |
Hydro-Generator Stator Winding ; Partial Discharge(PD) ; On/Off-Line Insulation Diagnosis ; Partial Discharge Analyzer(PDA) ; Frequency Spectrum Analyzer(FSA) |
Abstract |
In hydro-generator, a groundwall insulation of stator windings gradually deteriorates due to mechanical, thermal, electrical and environmental stresses. These stresses combine to result in loose windings, delamination of the stator insulation and/or electrical tracking of the endwinding, all of which can lead to stator insulation failures. Conventionally, off-line tests such as partial discharge measurement, DC/AC current and .DELTA.tan.delta. tests has been used for estimation of winding condition. However, off-line test requires large power supply and generator outage. In addition, major cause of insulation problems such as loose wedges and slot dischages may not be found with off-line diagnoses. This paper introduces the on-line partial discharge measurement techniques using frequency spectrum analyzer(FSA) for the generator stator windings. The experimental results from the UIAM #1 hydro-generator confirms a optimistic application of on-line generator diagnosis method as a reliable tool for evaluation of winding condition. |