At present

mechanical defects/fault are one of the most common problems of GIS equipment. Neither on -site detection devices nor mechanical defect evaluation methods are available for such defects now. In this paper

a comparative analysis of the vibration charac

teristics of different SF

6

gas compartments of 220 kV and 550 kV GIS has been performed by means of testing at site. The research results show that the amplitude of the three-phase bus compartment is the highest

the possible reason is that the magnetic induction intensity of the three-phase bus on the enclosure is larger

which makes the vibration amplitude of the enclosure larger. The correlation coefficients of amplitude-frequency characteristics of different measuring points of similar compartments are all above 0.993

and the correlation coefficients of different types of compartments are relatively low

indicating that the amplitude-frequency characteristics and their correlation coefficients can

to a certain extent

characterize the vibration states of different gas compartments of GIS. The correlation between amplitude and phase

detection position and voltage level is not strong. The main frequency component of most gas compartments is 100 Hz

and the main frequency variation of the arrester vibration is 300 Hz

which may be related to a slight defect inside the surge arrester..