Abstract:The vibration source can be accurately located by the time - frequency analysis that can analyze the causes of abnormal vibration of GIS and evaluate the equipment operating conditions. The wideband vibration testing system is used to detect the abnormal vibration of 220 kV GIS equipment. By means of spectrum analysis and continuous wavelet analysis of the measured vibration signals,the time domain and frequency domain characteristics of the vibration signal are studied. The analysis results show1the propagation attenuation characteristics of the vibration signal on GIS. The time delay of vibration signal is obtained by the wavelet entropy,therefore the vibration source is accurately located.