Statistical analysis of RF signals emitted by partial discharges

Electromagnetic radiation emissions from partial discharges (PD) can be measured, which could be helpful for avoiding unwanted asset disconnections in the power grid for insulation evaluation. These radio-frequency (RF) measurements do not require galvanic contact with high-voltage (HV) devices, which seems to be a clear advantage, but the lack of synchronization voltage makes PD source recognition a difficult task. Moreover, the presence of RF noise sources in the wideband required for PD detection, can lead to false warnings in the HV apparatus evaluation. In this paper, some specific parameters for signal characterization have been used to study noise and PD emissions. A digital acquisition system has been programmed to measure thousands of emissions from environmental noise and controlled PD sources in laboratory experiments to analyze the dispersive character of the recorded spectra.