Molecular Regulation and Physicochemical Properties of Synthetic Esters with High Onset Oxidation Temperature

Transformer in the power system to assume the task of electrical energy conversion and transmission, its reliability operation level is critical to the grid system. At present, the mainstream power transformers are oil-immersed insulation, insulation oil electrical and physical and chemical properties directly affect the safety of the entire power system. Synthetic ester insulating oil has high ignition point, green features, and can solve the problem of poor oxidation stability of natural ester insulating oil. the effect of molecular structure on the physicochemical properties and onset oxidation temperature of synthetic esters was investigated by regulating the molecular species and ratio, and a pentaerythritol insulating oil with a pour point of −35 °C, a kinematic viscosity of 31.4 mm
²
/s, a closed-end flash point of 225 °C and an onset oxidation temperature of 211 °C was prepared. The results show that the synthetic ester insulating oil obtained by molecular modulation has good physicochemical and electrical properties, and the onset oxidation temperature is comparable to that of mineral oil.