TY - JOUR

T1 - Partial Discharge Behavior of Epoxy Resin-impregnated Transformer Coils

AU - Borsi, H.

AU - Cachay, O.

N1 - Copyright: Copyright 2015 Elsevier B.V., All rights reserved.

PY - 1992/12

Y1 - 1992/12

N2 - This paper describes partial discharge (PD) investigations on industrially made epoxy-resin-impregnated transformer coils and coils produced under laboratory conditions in a temperature range between −30 and 180°C. The PD characteristics of the industrial coils can be reproduced with the simplified lab coils, and these results can be transferred to the industrial coils. The PD measurements show that the PD inception voltage decreases with rising temperature, which is explained with the superposition of two temperature-dependent phenomena. Firstly, the temperature-dependent rising values of the relative permittivity of the epoxy resin strengthen the electrical field inside the gas cavity. Secondly, the ignition condition, i.e. the relative gas density in the cavity, changes due to diffusion. From the observed voltage dependence of the repetition rate and phase position of the PD pulses and, with the help of a capacitive electrical circuit, it is shown that the measured PD’s are discharges in gas-filled cavities.

AB - This paper describes partial discharge (PD) investigations on industrially made epoxy-resin-impregnated transformer coils and coils produced under laboratory conditions in a temperature range between −30 and 180°C. The PD characteristics of the industrial coils can be reproduced with the simplified lab coils, and these results can be transferred to the industrial coils. The PD measurements show that the PD inception voltage decreases with rising temperature, which is explained with the superposition of two temperature-dependent phenomena. Firstly, the temperature-dependent rising values of the relative permittivity of the epoxy resin strengthen the electrical field inside the gas cavity. Secondly, the ignition condition, i.e. the relative gas density in the cavity, changes due to diffusion. From the observed voltage dependence of the repetition rate and phase position of the PD pulses and, with the help of a capacitive electrical circuit, it is shown that the measured PD’s are discharges in gas-filled cavities.

UR - http://www.scopus.com/inward/record.url?scp=0001517458&partnerID=8YFLogxK

U2 - 10.1109/14.204862

DO - 10.1109/14.204862

M3 - Article

AN - SCOPUS:0001517458

VL - 27

SP - 1118

EP - 1126

JO - IEEE Transactions on Electrical Insulation

JF - IEEE Transactions on Electrical Insulation

SN - 0018-9367

IS - 6

ER -