Nano-modifiers enhance the performance of natural ester transformer oils: challenges and future directions

Abstract

Natural esters exhibit excellent flame retardant and biodegradability, which help minimize power accidents and reduce environmental impact. These qualities make natural esters a promising alternative to conventional transformer insulating oils. However, the practical applications of natural esters in power equipment have been significantly restricted by their inherent limitations, including elevated viscosity, high dielectric loss, and poor oxidative stability. Nano-modification technologies present a novel methodological approach to solve these inherent constraints. A systematic analysis of the latest research developments in nano-modified natural ester transformer oils is provided in this review. The properties of various natural esters are examined, and their suitability as base fluids is evaluated, while the modification effects and mechanisms of typical nano-additives are comprehensively reviewed. The key role of nano-modification technology in improving the overall performance of natural esters is elucidated through detailed analysis of how nanoparticles influence physical properties, dielectric properties, and oxidative stability. In addition, the practical challenges facing nano-modification technology are addressed, providing valuable theoretical guidance for future developments in this field.

Graphical abstract

Keywords

transformer oil / natural ester / insulating oil / nanoparticles / dielectric properties

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Competing interests

The authors declare that they have no competing interests.

Acknowledgements

This work was financially supported by the Shanghai Sailing Program (Grant No. 24YF2744900), Research and Innovation Project of Shanghai Municipal Education Commission (Grant No. 2023ZKZD54), Industrial Collaborative Innovation Project of Shanghai (Grant Nos. 2021-cyxt1-kj37 and XTCX-KJ-2022-70), and Technical Standard Project of Shanghai (Grant No. 23DZ2201100).

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