Low temperature aging of XLPE and EP insulated cables with voltage transients

This paper presents the interim results of tests conducted on 15 kV crosslinked polyethylene (XLPE) and ethylene propylene (EP) insulated cables aged under identical conditions for 36 months at 30/spl deg/C (/spl plusmn/5/spl deg/C) with and without applied voltage transients. Aging voltages were from 1 to 2.5 times rated voltage. Failures during aging have occurred in EP insulated cable while none have occurred in XLPE insulated cable. Both types of cable experienced a large drop in AC and impulse voltage breakdown strength early in the aging process, There is an indication that voltage transients have slightly affected the AC and impulse voltage breakdown strength and contributed to the EP cable aging failures.<
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