Key Technologies For Ultra-Wideband Pds Detection In Transformer Under Ac/Dc Withstand Voltage Tests, Part 4: Feasibility Analysis Of Separation Or Grouping Technology Based On Pulse Current Sequence

Currently, the AC and DC withstand voltage PD test based on the traditional pulse current method with wideband or narrowband according the IEC 60270, the detection frequency band is only within 1 MHz, which greatly loses the information in time and frequency domain of the pulse current waveforms. So it is always difficult to eliminate the random interference pulse signals at the background of the substation, which seriously affects the test process. While the 4.6 “ultra-wideband instruments for PD detection” is defined based on PD pulse current waveform in the IEC 60270, but due to lack of the experimental research and engineering applications, no recommendations have been made for this type of method. In this paper, we summarized the characteristics of PD pulse current waveform in time and frequency domain, and intelligent analysis includes separation and clustering technologies, to make the feasibility analysis of anti-interference technology based on the PD pulse current sequence obtained using the ultra-wideband detection.