Analysis of the condition of dry transformers by acoustic emission measurement

This paper is focused on the description of the measurement and diagnostics analysis of two dry distribution transformers 22 / 0.4 kV, 0.8 MVA with epoxy resin winding insulation using acoustic emission analysis. It is one of the basic diagnostic and monitoring functions for remote measurement and acoustic measurement using acoustic camera. The dry distribution transformers generate acoustic emissions, thanks to which we can analyze the operating and fault condition of the device. The article presents the use of an acoustic camera for operational monitoring and diagnostics through noise from the winding source and the ferromagnetic core of the transformer. The spatial distribution of the acoustic field as well as its spectra were analyzed. Preliminary results have shown that acoustic analysis can be a useful alternative for analyzing the design state of a power transformer.