Analysis of the influence of loading on age of use of transformers in Botupingge substation

Abstract

The lifetime of a transformer cannot be determined with certainty due to several factors. One of them is the loading and ambient temperature that affects the transformer, especially at the Hot Spot temperature and the shrinkage of its age. The greater the loading, the higher the Hot Spot temperature so that the life span of the transformer is shorter. This study aims to determine the effect of loading on Hot Spot temperatures, loading forage losses and to determine the effect of loading on the 150kV / 20kV transformer life in the Botupingge Substation. The results of research at Botupingge Substation were obtained at 100% loading of 4.47 pu/day with an estimated age of 4.03 years, at 90% loading of 1.14 pu/day with an estimated age of 15.79 years, and at 80% loading of 0.33 pu/day with an estimated age of 54.55 years. Effect of maximum temperature with loading on 20 November 2018 results in a decreasing age of 0.3611 p.u / day on the type of refrigerant ONAN, and the shrinkage of the age of 0.0228 p.u / day on the type of ONAF cooler so that the estimated lifetime of the Botupingge substation transformer will reach 20 years.