In the operation of composite insulators, a break-off fault will lead to a vicious accident of falling off the line, seriously affecting the normal operation of the power grid. In recent years, a new phenomenon is different from brittle and usually fractured composite insulator decay fracture phenomenon, at present, at home and abroad for the core rod decay fracture is still in the preliminary research stage, to explore a composite insulator decay detection method is very important. Based on the characteristics of compound insulator decay fracture, this paper simulates and analyzes the effect of the degree of decay on the frequency of the low-order characteristics of the composite insulator, and explores the possibility of the detection method of the compound insulator decay defect based on the frequency of the lower-order feature. The simulation results show that the decay of composite insulators causes the frequency of its low-order features to shift, and its degree of offset increases with the increase of the depth and length of decay, so it is feasible to detect the decaying composite insulators by analyzing the low-order characteristic frequency of the composite insulators.

composite insulator,characteristic frequency,Decay-Like fracture,detection method,simulation