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., C4+F6, c-C4F6, and iso-C4F6) and multicomponent (e.g., C4F6/SF6/N2 and c-C4+F8/C4+F6/SF6/N2) gaseous systems have been tested and found to have better DC breakdown strength properties than SF6. These findings are reported and discussed.