Partial Discharge Induction with X-rays to Detect Void Defects in Solid Insulating Materials

Partial discharge (PD) diagnosis is a common method to detect physical defects such as air voids inside solid insulating materials. The X-ray induced partial discharge technique has been proved to facilitate the diagnosis process by supplying initiatory electrons inside the void by ionization. In this work, we examined the PD characteristics at continuous Xray exposure. The void samples fabricated in different sizes were exposed at varying dose rates. Under continuous X-ray exposure, PD was induced at a lower inception voltage as compared to the conventional PD tests. Average PD pulse height was recorded higher with a larger void. Pulse generation rate was higher for a larger void and also by exposure at a higher dose rate.