Title :
An analysis of AC conductivity in moist oil-impregnated insulation pressboard
Author :
Żukowski, PaweÅ‚ ; KoÅ‚tunowicz, Tomasz N. ; KierczynÌski, Konrad ; Subocz, Jan ; Szrot, Marek ; Gutten, Miroslav ; Sebok, Milan ; Jurcik, Jozef
Author_Institution :
Dept. of Electr. Devices & HV Technol., Lublin Univ. of Technol., Lublin, Poland
Abstract :
The paper presents research results of testing AC conductivity in a moist oilimpregnated electric insulation pressboard, depending on the moisture content level and temperature of the samples. A new method has been elaborated for converting experimentally obtained dependences from frequency-domain spectroscopy (FDS) to the reference temperature of 293 K (20 /dpl deg/C). Activation energy values have been determined for the conduction and relaxation time. It has been found the conductivity is realized by electron tunnelling between potential well formed by water molecules contained in the structure of moist cellulose.
Keywords :
insulating oils; insulation; tunnelling; AC conductivity analysis; FDS; activation energy; conduction time; electron tunnelling; frequency-domain spectroscopy; moist cellulose structure; moist oil-impregnated electric insulation pressboard; relaxation time; Conductivity; Frequency measurement; Insulation; Moisture; Permittivity; Temperature dependence; Temperature measurement;
Journal_Title :
Dielectrics and Electrical Insulation, IEEE Transactions on
DOI :
10.1109/TDEI.2015.004606
