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

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.

[1]  R. E. James,et al.  Condition Assessment of High Voltage Insulation in Power System Equipment , 2008 .

[2]  S. Boggs.  Partial discharge. III. Cavity-induced PD in solid dielectrics , 1990, IEEE Electrical Insulation Magazine.

[3]  P.J. Moore,et al.  Radiometric location of partial discharge sources on energized high-Voltage plant , 2005, IEEE Transactions on Power Delivery.

[4]  R. Bartnikas,et al.  Corona measurement and interpretation , 1979 .

[5]  Matilde Sánchez Fernández,et al.  Antenna Deployment for the Localization of Partial Discharges in Open-Air Substations , 2016, Sensors.

[6]  H Lee Willis,et al.  Aging Power Delivery Infrastructures , 2000 .

[7]  G. Robles,et al.  Statistical analysis of RF signals emitted by partial discharges , 2016, 2016 IEEE International Conference on Dielectrics (ICD).

[8]  B. T. Phung,et al.  Partial discharge localization in transformers using UHF detection method , 2012, IEEE Transactions on Dielectrics and Electrical Insulation.

[9]  J. Kuffel,et al.  High Voltage Engineering: Fundamentals , 1984 .

[10]  A. Nesbitt,et al.  Triangulation and 3D location estimation of RFI and Partial Discharge sources within a 400kV substation , 2009, 2009 IEEE Electrical Insulation Conference.

[11]  W. Marsden.  I and J , 2012 .

[12]  Guillermo Robles,et al.  Separation of Radio-Frequency Sources and Localization of Partial Discharges in Noisy Environments , 2015, Sensors.

[13]  B. G. Stewart,et al.  Evaluation of an iterative method used for partial discharge RF location techniques , 2011, 2011 10th International Conference on Environment and Electrical Engineering.