An experimental validation of partial discharge localization using electromagnetic time reversal

Abstract

The localization of partial discharge (PD) sources is of importance for the monitoring and maintenance of power transformers. Time difference of arrival (TDoA) based methods are widely adopted in the literature for the localization of PDs. Recently, time reversal (TR) was suggested as an efficient means to locate PD sources. As opposed to TDoA, which needs at least 4 sensors, TR is able to locate PD sources in power transformers with only one sensor. Moreover, it needs neither line-of-sight wave propagation from the PD sources to the sensor nor time synchronization. In this study, we present for the first time an experimental demonstration of the ability of the TR process to locate PD sources. A typical TR process includes three steps: (1) recording the PD-emitted field by a sensor, (2) time reversing and back injecting the signal into the medium, (3) using a proper criterion to obtain the focusing point which corresponds to the location of the PD source. In this work, we present a laboratory setup in which steps one and two are performed experimentally, both in the frequency and in the time domain. The obtained peak electric field value is used as a criterion in the third step. It is found that the accuracy of the proposed method is better than 2.5 cm in a transformer tank model with dimensions 73 × 73 × 103 cm3. The effects of the presence of scatterers such as transformer windings are also investigated experimentally and found not to affect the location accuracy of the method.

Partial discharge localization in power transformer tanks using machine learning methods

“…The volume of the transformer tank, as shown in Fig. 1, is 1000 × 500 × 500 mm 3 . The thickness of the tank walls is 10 mm.…”

“…Any malfunction in a power transformer can result in power outages and reduced reliability of electrical power networks. Therefore, the early detection and localization of PDs is crucial in order to prevent potential hazards and minimize further damage 2,3 .…”

An Inverse-Filter-Based Method to Locate Partial Discharge Sources in Power Transformers

“…More recently, time reversal (TR) in both the electromagnetic (EMTR) and the acoustic (ATR) regimes has been applied to locate PDs [15][16][17][18]. The TR technique can perform both 2D and 3D localization of multiple PD sources with only one sensor and does not require a line of sight.…”

Single-Sensor EMI Source Localization Using Time Reversal: An Experimental Validation

“…In [14], it was shown that the reflections from the surfaces of a cavity can emulate an infinite number of sensors in the time-reversal method. The idea presented in [14] was later successfully applied to the localization of partial discharges (PDs) in power transformers [24][25][26]. The method was also found to be robust against variations in the polarization and length of the PDs and also against environmental noise.…”