Improved Unitary and Multicomponent Gaseous Insulators

Improved unitary and multicomponent gaseous insulators are systematically designed according to detailed knowledge of fundamental electron-molecule interactions. Knowledge of the electron attachment and electron slowing-down properties of dielectric gases/mixtures as functions of electron energy is shown to be especially significant. On the basis of such knowledge it is possible to improve the gaseous dielectric´s breakdown strength by effectively controlling the numbers and energies of the electrons present. Several unitary (e. g. C4F6, c-C4F8, and iso-C4F8) and multicomponent (e. g. C4F6/SF6/N2 and c-C4F8/C4F6/SF6/N2) gaseous systems have been tested and found to have better dc breakdown strength properties than SF6. These findings are reported and discussed.