On-line monitoring of insulator contamination causing flashover based on acoustic emission

Conventional electrical measurements of polluted- insulator partial discharge (PD) activity have certain inherent limitations, which have prompted the research of non-electrical techniques. An acoustic emission (AE) monitoring method is presented in this paper. When a partial discharge occurs, there is an instantaneous release of energy, some of which is emitted as acoustic energy. Through detecting the sound signals, the pollution severities of insulators in-service can be monitored and accordingly threaten to the insulation of power grid is evaluated. Therefore preventive steps will be taken efficiently and quickly to avoid the happening of flashover. Artificial contaminations experiments are aid in acquiring important information about the relationship of AE signal and PD, in which the sound signals are obtained in different moments of flashover process. The studied method is a new way of AE technique in monitoring and characterizing defects of electrical power equipments in-service.