Study on characteristics of ultra-wideband partial discharge of typical insulation samples

In recent years, high frequency technique is applied for partial discharge detection extensively. Using the ultra-wideband partial discharge detecting system developed by authors, the characteristic of time-domain and frequency-domain of some typical insulation samples are studied. The ultra-wideband partial discharge characteristics of original epoxy sample involving cavities with cone-cone, needle-plate electrode system and epoxy sample involving metal interface with needle-plate electrode system are presented in this paper. And ultra-wideband partial discharge characteristics in aging process of insulation samples are also presented. From the experimental results, it is obvious that different types of partial discharge have their particular frequency characteristic and waveform, and can be distinguished in frequency-domain. It is important for insulation diagnosis