Gas Engineering Studies for High Pressure Self-Sustained Diffuse Discharge Closing Switches

摘要

The operating voltage and discharge stability of diffuse discharges for fast-closing switch applications are critically dependent on the variation of the ionization ( alpha /N) and attachment (eta/N) coefficients with E/N (gas density normalized electric field strength). Gases and gas mixtures which possess low (E/N)/sub lim/ values (i.e., the E/N value when anti alpha /N = alpha /N - eta/N = 0) and effective ionization coefficients, anti alpha /N, which vary slowly with E/N near (E/N)/sub lim/ lead to lower voltage (i.e., more efficient) operation with increased discharge stability. Several gas mixtures with these characteristics are discussed. It is argued that further improvements in switch efficiency and discharge stability can be obtained by adding a low ionization onset gas additive to these binary mixtures, such that at low E/N, alpha /N > eta/N, while at higher E/N, eta/N > alpha /N over a restricted E/N range. Several low ionization onset gas additives are suggested in this paper and the electron attachment and ionization coefficients in selected gas mixtures which possess these desirable characteristics are given. (ERA citation 12:029028)