The Application of Polyhedral Oligomeric Silsesquioxanes on Vegetable Insulating Oil Modification

Vegetable insulating oils, as promising substitutes for mineral insulating oils, have gained a lot of researches on their modification. Polyhedral Oligomeric Silsesquioxanes (POSS), a hybrid organic-inorganic nanoparticle, is of great prospect in vegetable insulating oil modification based on its remarkable dispersion property in organic liquids. In this research, the test material of vegetable oil (FR3, to be specified) was mixed with OctaMethyl-POSS (OM-POSS) in several different concentrations 0, 0.001, 0.004, 0.007 and 0.01 wt.% to make modified dielectric nanofluids. The AC breakdown strength and dielectric properties (relative permittivity, electrical conductivity and dissipation factor) of POSS-based oils were investigated. The experimental results showed that the AC breakdown strength of POSS-based nanofluids increased in a proper concentration range, while the permittivity, conductivity and dissipation factor of tested samples exhibited a reduction with proper POSS concentrations, where the model of interfacial zone was applied to explain the mechanism.