Application of Ester Liquids in Power Transformers

Power transformers are a key element in any grid, representing a significant financial investment. Their optimal operation is vital, as they form the backbone of energy delivery systems. The insulating liquid in these important machines must meet several criteria, including excellent dielectric and thermal properties, environmental sustainability, and low flammability. Historically, high-voltage transformers have relied on petroleum-based insulating liquids since the early 20th century. However, in recent years, sustainability has gained increasing importance, shifting the focus towards renewable resources and environmentally friendly alternatives to fossil fuels. Natural and synthetic esters, recognized for their superior environmental benefits and fire resistance, have emerged as a promising ecoconscious substitute for traditional petroleum-based oils. This paper aims to offer valuable insights into the role of ester liquids in improving the reliability and performance of transformers in modern power transformers. Key issues related to enhancing the performance of these liquids are also emphasized.