Mechanisms for degradation of TR-XLPE impulse strength during service aging

Author

Boggs, Steven A.

Author_Institution

Electr. Insulation Res. Center, Connecticut Univ., Storrs, CT, USA

Volume

17

Issue

2

fYear

2002

fDate

4/1/2002 12:00:00 AM

Firstpage

308

Lastpage

312

Abstract

While the retained AC strength of TR-XLPE distribution cable appears to be quite good at about 80% of the AC strength of degassed, as-manufactured cable, the impulse strength appears to drop linearly over time and has been reported to drop by as much as 50% during the first two years of normal service aging before leveling off. In this paper, we discuss the mechanisms by which the impulse strength can degrade to a greater degree than the AC strength. Three frequency-dependent mechanisms, which include electrothermal, electromechanical, and electrical, have been identified

Keywords

XLPE insulation; ageing; electric strength; power cable insulation; power distribution lines; trees (electrical); AC strength; EPR; TR-XLPE impulse strength degradation; distribution cable; frequency-dependent mechanisms; impulse breakdown strength; lightning impulse induced electrical phenomena; lightning impulse-induced electro-thermal-mechanical phenomena; lightning impulse-induced mechanical phenomena; normal service aging; service aging; tree retardant XLPE; Aging; Degradation; Dielectrics; Electric breakdown; Frequency; Lightning; Optical polarization; Power cables; Trees - insulation; Water heating;

fLanguage

English

Journal_Title

Power Delivery, IEEE Transactions on

Publisher

ieee

ISSN

0885-8977

Type

jour

DOI

10.1109/61.997887

Filename

997887