Use of Basic Physical Data in the Design of Multicomponent Gaseous Insulators

摘要

The multiple needs in high voltage (power) insulation dictate the development of a variety of gaseous insulating systems, each appropriate for the specific need. A variety of such optimal systems comprises multicomponent gas mixtures carefully designed as to components and properties on the basis of detailed physicochemical knowledge, especially on the interactions of low-energy (less than or equal to 20 eV) electrons with atoms and molecules. The use of basic knowledge on cross sections (especially sigma/sub a/(epsilon), sigma/sub sc/(epsilon) and sigma/sub i/(epsilon)), electron transport coefficients and their combination with cross sections via the Boltzmann transport equation to evaluate f(epsilon, E/P), negative ion states, electron affinities and other dynamic properties of molecular and ionic structure, the decomposition of the dielectric under electron impact, electric stress and/or after breakdown, and the required synthesis of pertinent basic knowledge is steadily leading us toward correlative relationships between basic properties and breakdown strength characteristics of gaseous dielectrics with predictive capabilities. The coupling of fundamental and applied studies in this area is a must. This will ensure their mutual feedback and will bring both closer to the realities of the practical, industrial and environmental constraints associated with the expanding use of dielectric gases.