Fabrication of Optical Fiber Sensors for Measuring Ageing Transformer Oil in Wavelength

In this paper, the fabrication and characterization of an optical fiber refractometer for detecting ageing transformer oil is presented. Tin-dioxide thin films have been used for the fabrication of optical fiber interferometers. Indium-tin-oxide thin films deposited on the optical fibers are used as the lossy mode resonance supporting coatings. This optical fiber sensor is based on the variation of an oil refractive index. This is detected by a wavelength shift in the optical fiber sensor's spectral response. The fabricated sensors enable an accurate determination of ageing transformer oil, which reveals their potential in real-life applications.