Measurement of Dielectric Characteristics of Transformer Liquids at Different Temperatures

Examining the alteration in the insulation characteristics of transformer dielectric liquid across varying ambient temperatures holds significant importance. When assessing the dielectric performance of an insulator, it is imperative to scrutinize capacity and resistance values. Given that environmental factors can induce fluctuations in these parameters, it is evident that the dielectric properties of transformer dielectric liquid would likewise vary under diverse conditions. Thus, the primary objective of this study is to measure the dielectric properties of oil at different temperatures. In this experimental investigation, various temperature settings were considered for natural ester, synthetic ester, and mineral oils commonly utilized as transformer oil. Across these temperature gradients and diverse frequency ranges, parameters including resistance and capacitance values were determined. Furthermore, examinations were conducted under DC high voltage for different temperature conditions. Unit step voltage experiments and insulation resistance tests were carried out across varying temperature levels.