Analysis of Factors Affecting Temperature Rise of Oil-immersed Power Transformer

Abstract

Abstract The key factors that affect the operation state of power transformer include thermal problem and insulation problem. It is of great significance to pay attention to the factors affecting the temperature rise characteristics of transformer to ensure its stable operation. The temperature rise characteristic model of transformer is established to explore the possibility of replacing mineral oil with plant insulation oil FR3 in this paper. On the basis of calculating the influence of ambient temperature change of external heat source on transformer temperature rise, the relative life loss rate of transformer under different ambient temperature is calculated. The results show that FR3 vegetable oil can replace mineral oil in terms of temperature rise. The temperature of the transformer core and winding hot spot increases with the ambient temperature. When the ambient temperature exceeds 293K, the relative life loss rate of the transformer increases very quickly. Therefore, the transformer should not be kept in an environment where the temperature exceeds 293K for a long time.