Accelerated aging of 15 kV cable insulated with standard and tree retardant XLPE

The evaluation of commercially available standard and TR-XLPE (tree-retardant cross-linked polyethylene) to the 1987 standard was carried out. The results have been compared to accelerated aging data obtained from miniature cable tests and from extensive full-size cable tests based on the 1982 standard. It was demonstrated that the commercial TR-XLPE insulation exhibited a greater resistance to electrical voltage than the standard XLPE as evidenced by its higher retention of breakdown voltage with aging. Significantly fewer and smaller bow-tie trees were observed in the TR-XLPE. There appeared to be no significant difference in vented tree growth in the two materials.<
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