No. 1336
	Recent Trend of Electrical and Acoustic Abnormality Diagnostic Technology for Oil-immersed�@Transformers
	Investigating R&D Transformer Committee
	Keyword : Transformer, Diagnosis, Partial discharge measurement method(UHF,AE), Frequency Response Analysis (FRA)
	For the Great East Japan Earthquake occurred, not only the safety�@ evaluation of power device, it is necessary to assessment the device�@during disasters. A sophistication of trouble diagnosis, lifetime diagnosis technology or degradation diagnosis has become more important to meet the conflicting needs of high reliability of equipment and economy. The report on maintenance and diagnosis technology of oil-immersed transformer titled "Recent Trend of Maintenance and Diagnosis Technology of Oil-Immersed Transformers" was posted in Technical report 1191 of IEEJ published in 2010,�@while�@diagnostic technology of aged transformer has attracted world attention, particularly, many reports regarding electrical and acoustic diagnostic techniques have�@been presented. In this committee, and�@conducted a study about research for dielectric correspondence analysis measures water amount of insulation materials, the partial discharge application method by AE and UHF, and diagnostic method by FRA, are summarized in this report.
	©2007. The Institute of Electrical Engineers of Japan