Simulation analysis on the propagation characteristics of electromagnetic wave in T-branch GIS based on FDTD

This paper investigates the propagation characteristics of partial discharge in Gas Insulated Substation (GIS). It is simulated based on the method of Finite Difference Time Domain (FDTD). Firstly the model for detecting PD signals in T-branch GIS is built according the real 220kV GIS experimental setup, and then we study the influence factors respectively. Also this paper makes experimental investigations on the propagation characteristics of PD induced by artificial insulation defect in real 220kV GIS. The simulation and experiment results show that the amplitude attenuation of electromagnetic wave has close contacts with pulse width and amplitude of the excitation source. This feature is used to determine the PD source type and evaluate the PD severity.