A novel acoustic method of partial discharge allocation considering structure-borne waves

• A novel PD allocation method based on acoustic sensors is proposed for power transformers.
• The structure-borne waves are considered for higher precision.
• Utilizing heuristic methods the location of PD is estimated with high precision.

For partial discharge, PD, allocating utilizing acoustic emission, AE, sensors, the arrival time of acoustic waves to the sensors forms the calculation basics, therefore, it is crucial that distance calculations are based on direct acoustic path. Considering structure-borne waves of higher speed, this would imply an incorrect distance between the source and sensor, because, AE signals of indirect path me be considered as AE signals of direct path. Therefore, a heuristic algorithm has been developed to consider the possible indirect paths. By comparing the time taken in each path of propagation, to reach the specified sensor location, the indirect path of shortest time for AE signal is determined. For experimental verification, a test oil chamber has been fabricated. PD signals are generated at different points inside the tank. The estimation results of algorithm have been compared with results of classic Time Difference of Arrivals method, TDOA. The proposed method considerably increases the PD allocation precision.