Spatial study of the uncertainties in the localization of partial discharges for different antenna layouts

Fresno, J.; Robles, G.; Martinez-Tarifa, J.; Stewart, B.; Spatial study of the uncertainties in the localization of partial discharges for different antenna layouts. 2017 IEEE International Instrumentation and Measurement Techonology Conference, Torino (Italy), May 22-25, 2017

https://doi.org/10.1109/I2MTC.2017.7969802

Abstract—The maintenance of high-voltage equipment is paramount to avoid blackouts or the interruption of electrical service. One of the most reliable methods to know the status of insulation systems is the measurement of partial discharges (PD). This phenomenon occurs when the dielectric presents imperfections due to ageing and degradation processes. Partial discharges are sudden releases of charge that can emit energy in a wide band of frequencies even in UHF. Therefore, antennas can be used, not only to detect the occurrence of PD, but to locate the source of emission and, consequently, the damaged asset. The localization can be done using multilateration measuring the time-differences of arrival (TDOA) of the pulses to an array of antennas. However, the onset of the signal is difficult to define due to numerous issues, from low signal-to-noise ratio, to lack of line-of-sight or errors in the positioning of the antennas. Then, the position of the source may have large uncertainties that even can prevent finding the asset at stake. The configuration of the antenna layout can help to minimize the effect of the uncertainties in the measurement of the TDOA. It has been found that there are configurations that favour certain bearings when locating the source giving more accurate results. This paper explores three type of antenna layouts and devises a method to determine what directions are best to orient the array.

Keywords—Antennas, Radio-frequency, Localization, Partial Discharges.