Title :
Dielectrometry measurements of effects of moisture and anti-static additive on transformer board
Author :
Du, Y. ; Zahn, M. ; Lesieutre, B.C.
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., MIT, Cambridge, MA, USA
Abstract :
Moisture in solid insulation has detrimental effects on transformer life. When the system is not in equilibrium laboratory measurements with multiple wavelength interdigital sensors using the imposed frequency-wavenumber (ω-k) dielectrometry technique have proved to be an effective way to measure complex permittivity distribution in solid insulation which is directly related to the moisture distribution. Measurements of oil-free and oil-impregnated pressboard using interdigital sensors with changes in ambient moisture concentration are presented. A comparison between existing moisture equilibrium curves for the oil-paper system and experimental results is given. Measurements are also performed for anti-static additive in oil and the dielectrometry effects are discussed
Keywords :
composite insulating materials; electrometers; insulation testing; interdigital transducers; life testing; moisture measurement; permittivity measurement; power transformer insulation; power transformer testing; anti-static additive; complex permittivity distribution; dielectrometry measurements; imposed frequency-wavenumber technique; moisture effects; multiple wavelength interdigital sensors; oil-impregnated pressboard; solid insulation; transformer board; transformer life; Frequency measurement; Laboratories; Moisture measurement; Oil insulation; Performance evaluation; Permittivity measurement; Power transformer insulation; Sensor systems; Solids; Wavelength measurement;
Conference_Titel :
Electrical Insulation and Dielectric Phenomena, 1997. IEEE 1997 Annual Report., Conference on
Conference_Location :
Minneapolis, MN
Print_ISBN :
0-7803-3851-0
DOI :
10.1109/CEIDP.1997.634600
