Análisis de cargabilidad y pérdida de vida útil de los transformadores de 500/230kV, instalados en el sistema nacional interconectado

Abstract

The transformer banks operate under different load profiles, as well as in different environmental conditions, both temperature, humidity, and altitude. This causes each of the transformers to age with a different rate of degradation. It is important to know the loss of life that each unit has suffered to anticipate the corresponding maintenance to reduce the risk of early failure of this equipment. Although the calendar useful life, estimated by the manufacturers of the transformers, is true, it is valid data to make a forecast of recovery of investments, O&M costs, among others, but it is not enough information to carry out technical analysis of the state. health, overload limits and overload times. For this reason, this document proposes an analysis of the chargeability and life span of the 500/230kV transformers installed in the 500 kV electrical transmission network of Ecuador. The energy source is the Coca Codo Sinclair generator, one of the largest hydroelectric large and important in Ecuador, for this reason there is a need to carry out a study to estimate the average life of the transformers, these teams that are in charge of transforming and delivering most of the energy to the country. The need to carry out a technical study is to be able to observe the behavior that it has had over the years since the transformers were put into service, to see in what conditions it is operating, considering that each substation is in different parts of the country, different altitude and different climatic changes, therefore, the same useful life of the transformer will not be had in each substation. The technical study implemented within this document is based on the IEC 60076-7 standard, which uses mathematical models to estimate the expected useful life of transformers using temperature and chargeability data that are taken routinely by operators in charge of each electrical substation. This study greatly helps operators to take timely actions on transformers and extends their service life.