Separation of sources in radiofrequency measurements of partial discharges using time-power ratios maps

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http://dx.doi.org/10.1016/j.isatra.2015.04.006

R. Albarracín, G. Robles, J.M. Martínez-Tarifa J.A. Ardila-Rey Separation of sources in radiofrequency measurements of partial discharges using time-power ratios maps. ISA Transactions, vol 58, pp. 389-397, 2015 (ISSN 0019-0578).

  • 2015 Impact Factor: 2.600
  • 6/56 (Q1) in ‘Instruments & Instrumentation’
  • Journal Impact Factor Percentile: 90.179

Abstract – Partial discharges measurement is one of the most useful tools for condition monitoring of high-voltage (HV) equipment. These phenomena can be measured on-line with antennas provided that the signal to noise ratio is improved by reducing common radiofrequency (RF) emission. One approach to this problem is the use of specific sensors like Vivaldi antennas which reject FM radio and low-frequency TV broadcasting bands. Additionally, the application of advanced signal processing techniques is paramount to separate noise and interferences from the signals of interest. In this paper, the power ratios (PR), a technique based on the power distribution of the incoming signals in frequency bands, is used to characterize different sources of PD and electromagnetic noise (EMN). The calculation of the time length of the pulses is introduced to separate signals where the PR alone do not give a conclusive solution. Thus, if several EM sources could be isolated and previously calibrated, it is possible to detect pulses that correspond to otherevents, quite possibly from PD activity.

Keywords – Partial discharges, dielectric materials, condition monitoring, RF measurements, VHF and UHF measurements, Vivaldi antennas, spectral power.