Copper contaminated insulating mineral oils-testing and investigations

Author

De Carlo, R.M. ; Bruzzoniti, M.C. ; Sarzanini, C. ; Maina, R. ; Tumiatti, V.

Author_Institution

Dept. of Chem., Univ. of Torino, Turin, Italy

Volume

20

Issue

2

fYear

2013

fDate

Apr-13

Firstpage

557

Lastpage

563

Abstract

Reactions between the liquid insulation and the copper conductors in power transformers and other electrical apparatus may lead to the formation of dissolved and suspended copper in the insulating oil. In this work a study concerning the correlation between the copper form and the dielectric properties of the fluid is presented. In particular, to determine the total copper content in oil and consequently to discriminate by subtraction the presence of particulate copper, we optimized a method of oil mineralization. Moreover, by filtering the oils with PTFE filters (0.45, 1 and 5 μm), the dimension of suspended copper content has been quantified and discriminated from the dissolved one: in such way, we investigated the influence of particulate copper on the characteristics of the oils and we determined the physical form that mostly affect the dielectric properties.

Keywords

conductors (electric); copper; dielectric losses; insulating materials; insulator contamination; minerals; power transformer insulation; transformer oil; Cu; PTFE filters; copper conductors; copper contaminated insulating mineral oil-testing; dielectric losses; dielectric property; electrical apparatus; liquid insulation; oil mineralization method; power transformers; size 0.45 mum; size 1 mum; size 5 mum; Copper; Dielectrics; Filtration; Lubricating oils; Mineralization; Copper in oil analysis; dielectric losses; non-sulfur corrosion; transformer oil; transformers;

fLanguage

English

Journal_Title

Dielectrics and Electrical Insulation, IEEE Transactions on

Publisher

ieee

ISSN

1070-9878

Type

jour

DOI

10.1109/TDEI.2013.6508759

Filename

6508759