Title :
Role of charge injection in AC aging of polyethylene in dry and humid environment
Author :
Svatik, A. ; Scarpa, P.C.N. ; Das-Gupta, D.K. ; Bulinski, A.T. ; Bamji, S. ; Densley, R.J.
Author_Institution :
Wales Univ., Bangor, UK
Abstract :
Thermal transient current (TTC) and thermally stimulated discharge current (TSDC) methods have been used to investigate the role of charge injection and trapping in cable-grade cross-linked (XLPE) and nonstabilized polyethylene (PE) samples aged in a dry and a humid environment. The TTC and TSDC data showed that in PE samples there is a nonuniform distribution of charge in the bulk. It is suggested that these charges are ions. PE samples aged at 65°C exhibited evidence of charge injection during DC poling at a higher temperature, due probably to higher oxidation levels or ion penetration during the aging. The observed responses differ from those in XLPE samples aged in dry oxygen, where TSDC peaks occurred at a lower temperature and were probably due to a presence of different types of localized states
Keywords :
ageing; cable insulation; electric breakdown of solids; environmental testing; insulation testing; life testing; localised electron states; organic insulating materials; polymer films; thermally stimulated currents; 65 C; AC ageing; DC poling; TSDC method; TTC; XLPE samples; cable grade cross-linked polyethylene; charge injection; charge trapping; dry O2; electrical stress; humid environment; ion penetration; localized states; nonstabilized polyethylene; oxidation levels; thermal transient current; thermally stimulated discharge current; Aging; Aluminum; Electrodes; Performance evaluation; Polyethylene; Steel; Stress; Temperature; Trees - insulation; Voltage;
Conference_Titel :
Electrical Insulation, Conference Record of the 1992 IEEE International Symposium on
Conference_Location :
Baltimore, MD
Print_ISBN :
0-7803-0649-X
DOI :
10.1109/ELINSL.1992.247044
