Spatially resolved and temporally integrated vacuum ultraviolet laser induced breakdown spectroscopy (VUV LIBS) was used for contaminant analysis in thermally aged oil impregnated pressboard (OIP) insulation material taken from high voltage transformers. The signature of copper sulphide contamination was obtained through detection of copper and sulphur emission lines. The plasma emission also contained highly ionized oxygen and carbon emission lines. In contrast to the UV-VIS spectral region, sulphur emission lines were found to be strong in the VUV region. The concentration of sulphur was found to increase with the duration of ageing of the OIP material. © 2019 Elsevier B.V.

Nilesh Jayanthilal Vasa

Department of Engineering Design

Ramanujam Sarathi

Department of Electrical Engineering

Atomic emission spectroscopy

Copper compounds

Electromagnetic wave emission

Insulating materials

LASER INDUCED BREAKDOWN SPECTROSCOPY

Sulfur

SULFUR COMPOUNDS

COPPER SULPHIDES

HIGH VOLTAGE TRANSFORMERS

INSULATION MATERIALS

OIL IMPREGNATED PRESSBOARD

Spatially resolved

SULPHUR EMISSIONS

transformer insulation

VACUUM ULTRAVIOLETS

ULTRAVIOLET LASERS

Fulltext

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Spectrochimica Acta - Part B Atomic Spectroscopy

In recent times, copper sulphide (Cu<inf>2</inf>S) diffusion in the transformer insulation is a major problem reducing the life of transformers. It is therefore essential to identify a simple methodology to understand the diffusion of Cu<inf>2</inf>S into the solid insulation [oil impregnated pressboard (OIP)]. In the present work, laser-induced breakdown spectroscopy (LIBS) was adopted to study the diffusion of Cu<inf>2</inf>S into the pressboard insulation and to determine the depth of diffusion. The diffusion of Cu<inf>2</inf>S in pressboard was confirmed by electrical discharge studies. In general, flashover voltage and increase in ageing duration of pressboard insulation/Cu concentration had inverse relationship. The characteristic emission lines were also studied through optical emission spectroscopy. Based on LIBS studies with Cu powder dispersed pressboard samples, Cu I emission lines were found to be resolvable up to a lowest concentration of 5 μg/cm2. The LIBS intensity ratio of Cu I–Ca II emission lines were found to increase with increase in the ageing duration of the OIP sample. LIBS studies with OIP samples showed an increase in the optical emission lifetime. LIBS results were in agreement with the electrical discharge studies. © 2014, Springer-Verlag Berlin Heidelberg.

Applied Physics A: Materials Science and Processing

Feasibility study for detecting copper contaminants in transformer insulation using laser-induced breakdown spectroscopy

Journal of Physics D: Applied Physics

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Materials Chemistry and Physics

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IEEE Transactions on Dielectrics and Electrical Insulation

Investigations of copper sulfide diffusion into paper insulation of transformers

Spectrochimica Acta Part B: Atomic Spectroscopy

Double-pulse laser induced breakdown spectroscopy with ambient gas in the vacuum ultraviolet: Optimization of parameters for detection of carbon and sulfur in steel

Vacuum ultraviolet laser induced breakdown spectroscopy for detecting sulphur in thermally aged transformer insulation material

Journal	Data powered by TypesetSpectrochimica Acta - Part B Atomic Spectroscopy
Publisher	Data powered by TypesetElsevier B.V.
ISSN	05848547
Open Access	Yes