Partial discharge process caused by GIS typical
insulation defect is mainly analyzed in this study, and
propagation properties of electromagnetic waves in actual GIS
structure are investigated by applying FDTD algorithm and
using real PD current signal as excitation source. The results
show that great difference occurs between electromagnetic waves
excited by PD actual current signal and that by ideal Gaussian
pulse excitation and basin type insulator, shielding electrodes and
three-phase common enclosure can affect the amplitude,
frequency component and propagation mode of electromagnetic
waves. The electromagnetic waves signal intensity is not
necessarily proportional to its distance from discharge source; the
proportion of frequency components is proportional to the
diameter of GIS shell when it propagate in breakers