Title :
Electrical and chemical diagnostics of transformers insulation. B. Accelerated aged insulation samples
Author :
Saha, T.K. ; Darveniza, M. ; Hill, D.J.T. ; Le, T.T.
Author_Institution :
Dept. of Electr. & Comput. Eng., Queensland Univ., Australia
fDate :
10/1/1997 12:00:00 AM
Abstract :
This paper describes the analysis of accelerated aged insulation samples to investigate the degradation processes observed in the insulation from aged power transformers. Short-term accelerated ageing experiments were performed on paper-wrapped insulated conductors and on pressboard samples. The condition of aged insulation samples was investigated by two relatively new diagnostic techniques: (a) measurements of interfacial polarization spectra by a DC method; and (b) measurements of molecular weight and its distribution by gel permeation chromatography (GPC). Several other electrical properties of the paper/pressboard samples were also studied. Possible correlations have been investigated among the different measured properties. The GPC results have been used to predict how power transformer insulation molecular weights change with temperature and time
Keywords :
ageing; chromatography; dielectric polarisation; electric breakdown; insulation testing; life testing; paper; power transformer insulation; power transformer testing; accelerated aged insulation samples; chemical diagnostics; electrical diagnostics; gel permeation chromatography; interfacial polarization spectra measurements; molecular weight; paper insulation; paper-wrapped insulated conductors; power transformer insulation diagnosis; pressboard samples; short-term ageing; Accelerated aging; Chemicals; Conductors; Degradation; Dielectrics and electrical insulation; Polarization; Power transformer insulation; Power transformers; Temperature; Weight measurement;
Journal_Title :
Power Delivery, IEEE Transactions on
