Surface modified h-BN towards enhanced electrical properties and thermal conductivity of natural ester insulating oil

Natural ester is regarded as a potential alternative to mineral insulating oil and has a wide range of applications in power system, but its electrical properties and thermal conductivity still need to be improved. Nano modification technology can improve the performance of natural ester to ensure the stability and reliability of natural ester in power equipment. In this study, nano modified natural ester is prepared with APTES surface modified h-BN, and the mechanism of enhancing the properties of natural ester is explored from the microscopic perspective by molecular simulation. The experimental results showed that nano h-BN had good dispersion stability in natural ester after surface modification with APTES. The electrical properties and thermal conductivity of the nano modified natural ester have been greatly improved, and the relative optimal doping concentration of nanoparticles is 0.03 g/L. The simulation results show that the interfacial thickness between nanoparticles and natural ester is larger and more tightly bound after surface modification, which is beneficial to reduce thermal resistance and improve thermal conductivity of natural ester insulating oil. The traps at the interface between nanoparticles and natural ester can capture free electrons in the oil, thus improving the breakdown voltage of natural ester insulating oil.