DocumentCode :
1280669
Title :
Discussion on possible additions to IEC 60897 and IEC 61294 for insulating liquid tests
Author :
Wang, Z. ; Liu, Quanwei ; Wang, Xiongfei ; Jarman, P. ; Wilson, G.
Author_Institution :
Sch. of Electr. & Electron. Eng., Univ. of Manchester, Manchester, UK
Volume :
5
Issue :
6
fYear :
2011
fDate :
7/1/2011 12:00:00 AM
Firstpage :
486
Lastpage :
493
Abstract :
IEC 60897 (determination of lightning impulse breakdown voltage, LIBV) and IEC 61294 (determination of partial discharge inception voltage, PDIV) are designed with the purpose of evaluating insulating liquids´ electrical property in a divergent field, and their current versions have existed for about two decades without revision. In view of the interest in the use of natural and synthetic esters in transformers, the suitability of IEC 60897 and IEC 61294 to evaluate new insulating liquids and the potential revisions are discussed here. Through comparative tests of mineral oil and esters, it is proposed that for IEC 60897, V´T (breakdown voltage´time to breakdown) curve should be obtained at overstressed voltages, i.e. voltages higher than LIBV, preferably under positive polarity, as a complement of LIBV. Similarly for IEC 61294, counting partial discharge (PD) numbers at overstressed voltages, i.e. voltages higher than PDIV, is proposed as a complement of PDIV. Overall, overstressing the liquids helps provide more information about electrical property of insulating liquid and thus can better assess a liquid for the purpose of insulation design. According to the above proposed procedure, both esters are found to be inferior to mineral oil in terms of lightning impulse property and PD behaviour.
Keywords :
IEC standards; electric breakdown; lightning; partial discharges; power transformer insulation; power transformer testing; transformer oil; IEC 60897; IEC 61294; LIBV; PD behaviour; PDIV; breakdown voltage time to breakdown curve; counting partial discharge; electrical property; insulating liquid tests; insulation design; lightning impulse breakdown voltage; lightning impulse property; mineral oil; partial discharge inception voltage; synthetic esters; transformers;
fLanguage :
English
Journal_Title :
Electric Power Applications, IET
Publisher :
iet
ISSN :
1751-8660
Type :
jour
DOI :
10.1049/iet-epa.2010.0209
Filename :
5960728
Link To Document :
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