General Switching Considerations

Abstract

Fundamentally, most switches in the “open” state may be viewed as a set of capacitor plates separated by a dielectric. The properties of the dielectric are such that it can be made conductive in some manner, such as ionization of a gas (thyratrons), injection of charge carriers into the conduction band (solid state), etc., or by injection of a conducting medium into the separating region (vacuum spark gaps). The readily available energy stored in the inter-electrode capacitance is dissipated internally to the switch and is important for rapid formation of a conducting plasma. In most cases a charge transport phenomenon through the previously insulating medium is required to maintain switch closure. In contrast, to recover to the “open” state, a deionization process is required.

The author wants to thank Dr. M. Giesselmann, Texas Tech University, for his help in preparing the manuscript.