Unlocked by Ergon – Transformer oil – e-lesson #18 – A detailed comparison of Ester fluids and mineral oils
Hosted by: CS Narasimhan / Master's level
Join us on July 16th at Transformers Academy!
This is the 18th lesson in the Transformer oil course, authored and presented by Mr. C. S Narasimhan. It is hosted on the Master's level. Here you can save your seat.
This lesson provides a detailed comparison of ester fluids and mineral oils used in transformers, focusing on their dielectric and heat transfer properties, design implications, and performance benefits. It examines the permittivity differences between the two liquids and how that impacts electrical stress distribution. The lesson also compares the lightning impulse behavior, AC breakdown, and streamer characteristics, highlighting the superior performance of mineral oils under highly non-uniform field conditions. However, under realistic transformer configurations, ester fluids demonstrate comparable dielectric performance. The thermal behavior of ester fluids is discussed, showing their higher operating temperatures but the ability to leverage this for increased transformer loading capacity. The lesson also covers the enhanced insulation life provided by ester fluids due to their moisture management capabilities. Finally, the presentation touches on the growing trend of retrofitting existing mineral oil-filled transformers with ester liquids.
Content of this lesson is fully vendor agnostic but it is sponsored by Ergon!
The lesson is intended for utility engineers/chemists, transformer and oil manufacturers, students and faculty of educational institutes, oil testing laboratories,utility staff, etc. It delivers a detailed comparison of Ester fluids and mineral oils with respect to Dielectric and heat transfer behaviour, design implications, performance benefits etc.
After the live broadcasting, the lesson stays available on demand.
About the author
CS Narasimhan
Dr. Narasimhan holds PhD in chemistry from a premier institute IIT Madras, Chennai (India), with a long experience of about 40 years. He has been working in corporate R&D centers of multinational companies ever since he completed his PhD in 1978.
He was heading R&D at Savita Oil Technologies in Mumbai for 20 years, until his recent retirement.
His R&D work includes: developing a variety of grades of transformer oils based on paraffinic oils, naphthenic oils, natural esters and synthetic esters,
application development in transformers, developing additives for transformer oils, studying oxidation behavior, moisture dynamics in oil-filled transformers, studies on dielectric properties of mineral oils and esters (impulse & power frequency), insulation paper ageing studies in mineral oils and ester oils published papers in the recent ICDL conference in Rome and 9 papers in IEEE conferences on dielectric properties of ester oils and mineral oils, and more.
He has published more than 30 papers, of which 15 are on transformer oils, and is proud of his six patents.
He has been an invited speaker at conferences in India and abroad, as well as delivered lectures at seminars conducted by Weidman in Europe. He is a member of two IEC committees on oil standards and a member of two CIGRE committees on oils.
