Partial discharge localization and classification using acoustic emission analysis in power transformer

Transformers are a major capital item and the cost of a failure is high both in direct costs and downtime. For this reason they are monitored using a variety of methods. Partial discharges in power transformers are often a predecessor of a serious fault for this reason. Partial discharge measurements are an important diagnostic tool to monitor the insulation condition of a transformer. For on-line measurements, a detection method based on the acoustic signals emitted by the discharging source is used and can be detected. Moreover, the acoustic technique offers the possibility to locate and identify the PD source. This paper covers general aspects of acoustic methods for PD detection and localization in time, frequency and time-frequency domain.