Effective ionization coefficients and limiting field strength of fluoronitriles-CO2 mixtures

Houssem Eddine Nechmi (1) , Abderrahmane Beroual (1) , A. Girodet (2) , P. Vinson (2)

1 EE - Ampère, Département Energie Electrique
2 SuperGrid Institute SAS

The density normalized effective ionization coefficients and critical breakdown electric field of the Heptafluoro-iso-butyronitrile (Fluoronitriles), and Fluoronitriles-CO2 mixture are investigated using the steady state Townsend (SST) experimental setup, over a range of the density normalized critical electric field (E/N) from 200-1066 Td (E is the electric field and N the gas density). Breakdown voltage measurements are also performed to plot the Paschen curves for small product values (N×d) (d being the electrode gap), to identify the Paschen minimum, and to validate the density normalized critical electric field (E/N)0 when α=η (α and η are the ionization and attachment coefficients, respectively). The influence of electrode surface roughness is also analyzed.

Mots clés: Heptafluoro-iso-butyronitrile; fluoronitriles/CO2 mixtures; effective ionization coefficient; dielectric breakdown; roughness effect

Domaines: Energie électrique

Houssem Eddine Nechmi, Abderrahmane Beroual, A. Girodet, P. Vinson. Effective ionization coefficients and limiting field strength of fluoronitriles-CO2 mixtures. IEEE Transactions on Dielectrics and Electrical Insulation, 2017, 24 (2), pp.886 - 892. ⟨10.1109/TDEI.2017.006538⟩. ⟨hal-01588209⟩