Molecular dynamics simulation on thermal stability of oil-paper insulation

To explore the microscopic mechanism of thermal stability of oil-paper insulation， a molecular model consistent with the actual oil-paper insulation is established. Through comparison with the experimental results， the effectiveness of the model is verified. With temperature as an independent variable， variation of the mechanical parameters and hydrogen bond energy of the cellulose molecular model under the action of a thermal field is investigated. The results show that parameters characterizing the mechanical properties of cellulose， such as bulk modulus （K）， Young's modulus （E）， shear modulus （G）， and Poisson's ratio （v） of the cellulose crystalline zone model are larger than those of the amorphous zone model at the same temperature， and the distribution of hydrogen bond energy remains the same. Thus， the cellulose crystalline zone is superior to the amorphous zone in mechanical properties and determines the insulation properties of cellulose insulating paper. The results of the study provide a theoretical basis and method for investigating the microscopic mechanism of thermal aging of oil-paper insulation.