Classification of leakage current odd harmonic component of aged insulator surface condition under different relative humidity using crest factor

The impact of pollution on insulator surface performance has been extensively studied to continuously improve the insulator performance using suitable condition monitoring, including using the leakage current harmonic component analysis. However, the analysis of harmonic components, particularly in relation to the odd harmonics of the leakage current in aged insulators under the influence of contamination and humidity, is still not fully understood and remains deficient. In this paper, the leakage current of aged and polluted insulators under different environmental conditions are investigated. The study was conducted experimentally using twelve samples of insulators with varying degrees of aging. The crest factor was employed as an indicator of the leakage current index. The findings showed that the odd harmonic crest factor demonstrates high sensitivity in classifying the degree of aging in contaminated insulators.