Study of EM wave propagation characteristics in GIS is meaningful to analyze and localize partial discharge sources.First

based on the finite integration technique

the simulation of S parameters was performed to analyze changes of S parameters with the number of basin-type insulators.Meanwhile

a 252 kV GIS experiment platform was established

where signals from different positions could be obtained by inner sensors.Compared with S parameters calculated from experiments

the simulation results

which showed a good consistency both in waveform and amplitude

were proven to be reasonable.Moreover

a vector network analyzer was used to measure S parameters in different structures of GIS

and simulation models were refined and changed.The results of vector network analyzer were compared with those of simulation which had a good consistency and proved the rationalisation of the simulation conclusion.The results show that the attenuation influence of one insulator can be up to-3 d B

which is in proportion to the number of insulators.