Transformers Magazine, Vol. 12 No. SE1, 2025.
Original scientific paper
Historical evolution of organic and insulating liquids: From whale oil to mineral and vegetable oil
Marius Grisaru
Abstract
Vegetable oils, although recognized early for their insulating potential, were largely dismissed as transformer-insulating liquids during the formative years of electrical engineering. This column explores the technical and historical reasons behind the preference for mineral oils over vegetable oils 100 years ago, analyzing early research findings and practical considerations. Key aspects such as oxidation stability, moisture absorption, low-temperature performance, gas absorption, and material consistency are examined alongside the technological limitations of the early 20th century. The timeline of the appearance and disappearance of various animal, vegetable and mineral oils is also detailed. A brief, non-chemist explanation of the molecular structure differences between esters and mineral oils is also provided.
Keywords
mineral oil; vegetable oil; natural esters, synthetic esters; oxidation stability; moisture absorption; biodegradability; dielectric properties; fire safety
Hrčak ID:
331607
URI
Publication date:
19.5.2025.
Visits: 610 *