Aging of paper insulation in natural ester dielectric fluid

Author

McShane, C. Patrick ; Rapp, Kevin J. ; Corkran, Jerry L. ; Gauger, Gary A. ; Luksich, John

Author_Institution

Dielectric Fluids Group, Cooper Power Syst., Waukesha, WI, USA

Volume

2

fYear

2001

fDate

2001

Firstpage

675

Abstract

Aging of transformer insulation paper in natural ester (vegetable oil) dielectric fluid is compared to that in conventional transformer oil. Sealed steel aging vessels containing copper, aluminum, thermally upgraded paper, and dielectric fluid (mineral oil and natural ester) were aged at 130, 150 and 170°C for 500, 1000, 2000 and 4000 hours. Paper degradation after aging is determined using paper tensile strength and degree of polymerization measurements. The paper in natural ester aged at slower rates than did paper in conventional transformer oil, taking 5-8 times longer to reach end-of-life. Results obtained for mineral oil samples are similar to predictions based on IEEE transformer loading guide calculations. Mechanisms for the slower aging rate are proposed

Keywords

ageing; electric breakdown; insulation testing; life testing; paper; power transformer insulation; power transformer testing; transformer oil; 1000 h; 130 C; 150 C; 170 C; 2000 h; 4000 h; 500 h; IEEE transformer loading guide calculations; insulation breakdown testing; natural ester dielectric fluid; paper degradation; paper tensile strength; polymerization degree; power transformer insulation paper ageing; sealed steel aging vessels; slower aging rate; vegetable oil; Aging; Aluminum; Copper; Dielectrics and electrical insulation; Minerals; Oil insulation; Petroleum; Power transformer insulation; Steel; Thermal degradation;

fLanguage

English

Publisher

ieee

Conference_Titel

Transmission and Distribution Conference and Exposition, 2001 IEEE/PES

Conference_Location

Atlanta, GA

Print_ISBN

0-7803-7285-9

Type

conf

DOI

10.1109/TDC.2001.971319

Filename

971319