Acoustic Emission Transformer Partial Discharge Location

 

Partial Discharge (PD) is an electrical phenomenon that occurs within a transformer whenever the voltage load is sufficient to produce ionization, and partially bridges the insulation between conductors. In an operating transformer, any PD is a cause for concern.

 

Partial discharges are pulse-like in nature and cause mechanical stress waves (Acoustic Emission) to propagate within the transformer. These stress waves propagate throughout the surrounding oil and can be detected at the transformer tank wall. By measuring the relative time of arrival of the acoustic wave at multiple Acoustic Emission Sensors located on the transformer tank wall, the 3D location of the PD within the transformer can be determined. For this reason, Acoustic Emission sensing offers a good, real time solution to both PD detection and PD source location.