Breakdown Characteristics and Pre-Breakdown Phenomena

in Liquid and Boiling Nitrogen with Tape Electrode for r-SCFCL Applications

The rational insulation design of a resistive superconducting fault current limiter (r-SCFCL) requires data gathered from experimental setups relevant for the final apparatus. Therefore, an experimental study was performed to characterize the electrical breakdown (BD) of liquid nitrogen (LN2) in the peculiar conditions of a quenching superconducting device. To reproduce the electrical stress occurring within a real r‑SCFCL winding, BD voltages with a grounded tape electrode were investigated with different gap distances and polarities, with and without transient heating of the tape electrode. Pre-disruptive phenomena (streamers) were observed, and their phenomenology was compared to previous knowledge of streamers in LN2.

Keywords: Liquid nitrogen, boiling nitrogen, streamers, breakdown voltage, r-SCFCL, H2020 FASTGRID project, high voltage insulation

R. CHASSAGNOUX (1, 2), O. Lesaint (2), O. Gallot-Lavallée (2), N. Bonifaci (2), S. Flury (2), J-L. Palenzuela (2),
P. Legendre (1), C. Creusot (1), A. GIRODET (1)

(1) SuperGrid Institute SAS, 21 rue Cyprian, 69 611 Villeurbanne Cedex, France
 (2) Univ. Grenoble Alpes, CNRS, Grenoble INP*, G2Elab, F-38000, Grenoble, France

Conference: SFE 218: 11eme conférence de la société française d’electristatique 29-31 aout