Closing Switches

Closing switches are required to withstand high voltages and then rapidly enter a conducting state that will pass high currents with minimal losses. This chapter describes spark gap closing switches in considerable detail because of their ubiquitous use in pulsed power technology. It then describes other closing switches, including thyratrons, ignitrons, and pseudospark switches, as well as commercially available solid‐state switches. A spark gap is comprised of two conducting electrodes separated by an insulating medium, usually a gas, but liquids or vacuum are also used. The pseudospark switch exhibits remarkable switching properties, combining the advantages of thyratrons and spark gaps, specifically high dI/dt, reverse current, and charge transfer capabilities, along with long lifetime and low jitter. A solid dielectric switch consists of two main insulation sheets, a trigger insulation foil, and two metallic foils sandwiched between the main electrodes E₁ and E₂ by an external clamping force.