Classification of aging level of solid dielectric using Fourier transform infrared spectroscopy — Method of discriminant analysis

The main objective of this paper is to investigate the possibility of application of Fourier transform infrared spectroscopy and method of discriminant analysis for classification of a solid dielectric. Classification method was determined by applying accelerated thermal aging on glass-mica-based insulating system material. Based on previous experience and on the thermal class of the insulating system, the aging temperature was set to 170 °C. Infrared spectra were measured after 192, 384, and 600 hours of aging using technique of Attenuated Total Reflectance in the middle area of the infrared electromagnetic spectrum (4000-600 cm^-1). Regarding the results, it is possible to state that the method of discriminant analysis in connection with Fourier transform infrared spectroscopy can be regarded as a proper diagnostic indicator of aging for material of insulating systems.