In this paper, the effect of polarity on prebreakdown phenomena in perfluorinated polyether (PFPE) under non-uniform field was investigated. The inception and propagation of streamers were observed using a high speed and high magnification shadowgraph system. The current pulses were also measured simultaneously using a LED current pulse measurement system. The streamer inception voltage for both polarities were -9.99 kV and +12.86 kV, respectively. The deviation of time delay from the voltage application to the streamer inception was larger for a positive point than a negative. The initial shape of the negative streamer was a filament which emanated from a needle tip. On the other hand, for a positive point, a filamentary streamer started at about 9 μm away from a needle tip, and propagated toward a needle tip. These experimental results suggested that the inception of a positive streamer needs much higher field than a negative one due to the higher ionization potential of fluorine atom in PFPE as well as breakdown voltage.
Simultaneous measurements of streamer and partial discharge processes in perfluorinated polyether / H., Yamashita; M., Okumura; K., Yamazawa; Pompili, Massimo; MAZZETTI DI PIETRALATA, Carlo; E. O., Forster. - STAMPA. - 2:(1994), pp. 610-613. (Intervento presentato al convegno Proceedings of the 1994 IEEE 4th International Conference on Properties and Applications of Dielectric Materials. Part 2 (of 2) tenutosi a Brisbane, Aust nel 3 July 1994 through 8 July 1994) [10.1109/icpadm.1994.414084].
Simultaneous measurements of streamer and partial discharge processes in perfluorinated polyether
POMPILI, Massimo;MAZZETTI DI PIETRALATA, Carlo;
1994
Abstract
In this paper, the effect of polarity on prebreakdown phenomena in perfluorinated polyether (PFPE) under non-uniform field was investigated. The inception and propagation of streamers were observed using a high speed and high magnification shadowgraph system. The current pulses were also measured simultaneously using a LED current pulse measurement system. The streamer inception voltage for both polarities were -9.99 kV and +12.86 kV, respectively. The deviation of time delay from the voltage application to the streamer inception was larger for a positive point than a negative. The initial shape of the negative streamer was a filament which emanated from a needle tip. On the other hand, for a positive point, a filamentary streamer started at about 9 μm away from a needle tip, and propagated toward a needle tip. These experimental results suggested that the inception of a positive streamer needs much higher field than a negative one due to the higher ionization potential of fluorine atom in PFPE as well as breakdown voltage.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
