Prebreakdown currents at AC are mainly determined by emission currents, if the capacitive current component is compensated. Under certain conditions, which are dealt with in this study, HF (high-frequency) impulse currents are superimposed. The shape of the HF impulse current curve as a function of time was recorded with a high time resolution. The steepness of relevant current jumps has been evaluated. On the basis of the results the phenomenon of HF impulse currents is interpreted as a consequence of changing gas attachment to the metallic electrodes
Published in:
Electrical Insulation, IEEE Transactions on
(Volume:24
,
Issue:
6
)
Date of Publication: Dec 1989