Propagation of positive and negative streamers in oil with and without pressboard interfaces

Inception and propagation of streamers in a point-plane gap, with and without pressboard interface parallel to the field, have been studied. Current and light emission have been recorded. Positive streamers propagate at /spl sim/2 to 4 mm//spl mu/s at voltages to 2/spl times/ the minimum breakdown voltage. Above this voltage, a fast event (>100 mm//spl mu/s) may occur, preceded by streamers propagating with velocities in the 10 to 20 mm//spl mu/s range. The negative streamers have /spl sim/2/spl times/ the breakdown voltage as the positive ones. Even negative streamers may develop into a slower kind of fast event. Solid pressboard parallel to the field does not change the breakdown voltage, but makes inception of fast events easier. The breakdown process in oil shows several similarities to a gas breakdown.

[1]  J. C. Devins,et al.  Breakdown and prebreakdown phenomena in liquids , 1981 .

[2]  Olivier Lesaint,et al.  Initiation and propagation thresholds of positive prebreakdown phenomena in hydrocarbon liquids , 1994 .

[3]  H. Yamashita,et al.  Pre-Breakdown Current and Light Emission in Transformer Oil , 1984, IEEE Transactions on Electrical Insulation.

[4]  O. Lesaint,et al.  Study of streamer propagation in mineral oil in overvolted gaps under impulse voltage , 1995, Proceedings of 1995 Conference on Electrical Insulation and Dielectric Phenomena.

[5]  Yu.V. Torshin On the existence of leader discharges in mineral oil , 1995 .

[6]  W. G. Chadband,et al.  On variations in the propagation of positive discharges between transformer oil and silicone fluids , 1980 .

[7]  T. O. Rouse,et al.  Influence of aromatic compounds in oil on pirelli gassing and impulse surge breakdown , 1975, Conference on Electrical Insulation & Dielectric Phenomena - Annual Report 1975.

[8]  P. Atten,et al.  Potential distribution along single negative creeping streamer in transformer oil , 1993 .

[9]  Y. Kamata,et al.  Flashover Characteristics of Extremely Long Gaps in Transformer Oil under Non-Uniform Field Conditions , 1980, IEEE Transactions on Electrical Insulation.

[10]  R. Tobazcon Prebreakdown phenomena in dielectric liquids , 1994 .

[11]  W. G. Chadband,et al.  A pre-breakdown phenomenon in the liquid dielectric hexane , 1965 .

[12]  O. Lesaint,et al.  On the gaseous nature of positive filamentary streamers in hydrocarbon liquids. II: Propagation, growth and collapse of gaseous filaments in pentane , 1994 .

[13]  Olivier Lesaint,et al.  On the gaseous nature of positive filamentary streamers in hydrocarbon liquids. I: Influence of the hydrostatic pressure on the propagation , 1994 .

[14]  O. Lesaint,et al.  Propagation of streamers in mineral oil at large distances , 1994, Proceedings of IEEE Conference on Electrical Insulation and Dielectric Phenomena - (CEIDP'94).

[15]  O. Lesaint,et al.  A study of the inception of positive streamers in cyclohexane and pentane , 1993 .

[16]  J. Devins,et al.  Streamer Propagation in Liquids and over Liquid-Solid Interfaces , 1982, IEEE Transactions on Electrical Insulation.

[17]  P. Biller A simple qualitative model for the different types of streamers in dielectric liquids , 1996, ICDL'96. 12th International Conference on Conduction and Breakdown in Dielectric Liquids.

[18]  A. Beroual,et al.  Prebreakdown Phenomena in Liquid Dielectrics , 1986, IEEE Transactions on Electrical Insulation.