• Jarman, P. N.
• Pilgrim, James
• Facciotti, M.
• Wilson, G.
• Brown, Richard
• Lewin, Pl
• Amaro, P. S.

Abstract

The effects of corrosive sulphur in oil-filled power assets have been extensively studied over the last decade, as have remedial strategies to combat their impact. Passivation of the metal conductor by adding an organic passivator (e.g. Irgamet™39) to the insulating oil remains one of the preferred mitigation approaches due to its favourable cost-performance ratio. Recent approaches to the study of the chemistry of copper passivation and corrosion in insulating liquids are described using analytical tools typical of surface science. An overview of the physical principles involved is provided, followed by examples describing applications of XPS (X-ray photoelectron spectroscopy) and SSIMS (static secondary ion mass spectrometry). The advantages of these techniques are discussed, together with a critical evaluation of their limitations, in fundamental studies of passivation performance. Finally, their possible use as post-mortem diagnostic tools for power transformers is discussed.

Topics

• impedance spectroscopy
• surface
• corrosion
• x-ray photoelectron spectroscopy
• copper
• spectrometry
• secondary ion mass spectrometry
• Sulphur