Analysis of Aging Degree of Composite Insulators Based on Joint Relaxation Spectrum

In power systems, composite insulators are subjected to strong electric fields and environmental corrosion, and will age and affect the electrical insulation effect; however, existing insulator aging detection methods are limited by the test environment, and it is difficult to intuitively reflect the microchemical structure changes of silicone rubber materials. In this paper, the NMR relaxation spectrum analyzer and CPMG signal were used to verify the feasibility of T2 relaxation spectrum for aging degree detection, and the combined sequence of IR-CPMG was proposed to experiment on composite insulators with different aging years. The results show that detecting the signal amplitude of the joint sequence and inverting the two-dimensional relaxation spectrum can visually characterize the change of the main hydrogen-containing group from the height and volume of the joint spectral peak, and effectively distinguish the composite insulators with different aging degrees.