13 / 2022-02-21 12:18:51

Experimental Study on Thermal Aging Properties of Solid Insulating Materials for Transformers

Thermal Aging Properties,Solid Dielectrics,Surface Morphology,Mechanical Properties,Surface Absorbance

Thermal aging is one of the typical causes of premature failure of the insulation capacity of solid dielectrics, which seriously affects the insulation life of transformers. At present, the thermal aging properties of various solid dielectrics need to be studied. In this paper, changes in the surface morphology, mechanical properties and surface spectral properties of solid insulating materials during thermal aging were analyzed. The research results in this paper provide a reference for the comprehensive analysis of the thermal aging state of transformer insulation. In this paper, a thermal aging simulation test platform was established and samples of Nomex paper, PET film and PI film with different aging degrees were prepared. Subsequently, the change of surface morphology of insulating materials during thermal aging was analyzed under the scanning electron microscope, and the mechanical properties of insulating films were tested based on the mechanical testing system. Meanwhile, the changes of surface absorbance under different thermal aging degrees were analyzed based on Fourier transform infrared spectrometer. With the deepening of thermal aging, the insulating material exhibits changes in color deepening, increasing degree of curling, surface fiber ablation, and the appearance of holes. At the same time, the tensile strength, elongation at break and surface absorbance decreased gradually with the prolongation of thermal aging time. During the gradual deepening of thermal aging, the morphological, mechanical and surface spectral characteristics of solid dielectrics show regular changes. The experimental results in this paper provide a reference for the analysis of the aging state of transformer insulation.