Localisation of single and multiple partial discharge sources based on sequence of arrival and levels of peak amplitude of acoustic emissions

Partial Discharge (PD) is one of the most critical electrical phenomena affecting the life of electrical equipment. Repetitive PD can lead to gradual deterioration of the insulation, which may further lead to complete failure of the electrical insulation. Hence, detection and localization of PD inside electrical equipment is necessary for early detection of impending failure. Keeping this in mind, this paper proposes a methodology to localize single and multiple PD sources based on acoustic signals emanated from such sources. The localization has been done based on sequence of arrival and levels of peak amplitude of acoustic waves. The proposed approach makes use of a low complexity methodology for PD localization without the use of complex classification tools. The results show that this developed methodology is able to localize the single and multiple PD events with considerable accuracy.

I. Introduction

Partial Discharge (PD) phenomena is a localized electrical discharge within any insulation system, as applied in electrical apparatus, components or systems, that only partially links the insulation between conductors which may or may not occur adjacent to a conductor [1], [2]. Generally partial discharges take place due to local electrical stress concentrations appearing within voids or bubbles inside the insulation or on the surface of the insulation. Every discharge event causes chemical transformations of many types due to impact of short-time avalanche of high energy electrons or accelerated ions. This in turn results into gradual deterioration of the material and may further lead to ultimate failure of the apparatus involved, if unchecked [1]–[4]. Hence presence of partial discharge in an apparatus is an indication to transpiring dielectric defects in the insulation of the apparatus. Early detection and localization of such discharges may prevent the impending apparatus outage and the resulting inconvenience or revenue loss.