Acoustic Based Localization of Partial Discharge Inside Oil-Filled Transformers

Abstract

This paper addresses the localization of Partial Discharge through a 3D Finite Element Method analysis of acoustic wave propagation inside a 3-phase 35kV transformer with the help of COMSOL Multiphysics software. Due to the complexity inside transformers, acoustic waves generated by PDs cannot simply be detected with typical acoustic sensors, especially when PDs happen inside inner windings. These waves are distorted and attenuated along with their propagation. The type, number, and position of sensors are essential factors in PD localization inside a transformer. A new installation arrangement of fiber-optic acoustic sensors inside the transformers is proposed with this information. This array of acoustic sensors has significant effects on PD localization accuracy and has immunity from on-site noise and interference; more importantly, they can be installed after transformer manufacturing. They are reachable if needed to be repaired or replaced. Several numerical studies have been carried out considering different PD source positions, and the Levenberge-Marquardt algorithm is employed for solving localization equations.