Study on Electrothermal Aging of Insulation Pressboard Based on Molecular Simulation

Insulation faults are one of the most common types of faults in transformers. The insulation pressboard is an important component of the insulation system of the converter transformer, and its main component is cellulose. At present, research on the aging of insulation pressboard mostly focuses on conducting aging tests, which cannot reveal the aging mechanism well. To understand the changes at the micro level during the aging process of insulation pressboard. From the molecular simulation point of view, in this paper we first develop a cellulose chain equivalent model and then build on this to develop an insulation pressboard equivalent model. The thermal and electrical thermal fields are applied separately to simulate the aging process of the insulation pressboard. After a period of physical field application, the energy of the system, the number of hydrogen bonds in the model, and the molecular mean square displacement (MSD) are detected; Finally, the simulation results are processed and analyzed. It has been found that temperature and electric field can lead to changes in the detection index, which can damage the structural stability of the insulation pressboard and cause the insulation pressboard to age.