Research on the Operating Characteristics of Electrically Triggered Vacuum Surface Flashover Switch

Abstract

A novel configuration of electrically triggered vacuum surface flashover switch (VSFS) is introduced, and switches based on alumina, quartz, and aluminum nitride are fabricated. The main switch operation characteristics (flashover voltage, turn-on time, delay time, jitter, repetitive frequency ability, and lifetime) and their influencing factors (operation voltage, loop current, trigger current, and trigger waveform) are experimentally investigated. The results show that the dc flashover voltages for both switches tested in vacuum are 2–4 times higher than the voltages tested at 1 atm. The switch turn-on time is mostly affected by the operation voltage and loop resistance, while the switch delay time is mainly influenced by the front edge of the trigger voltage pulse. Delay times of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\approx 70$ </tex-math></inline-formula> ns with a corresponding jitter of less than 3.1 ns are observed for both switches. The repetitive frequency ability of both switches is better than 60 Hz@27.5 kV and can reach 100 kHz@6 kV. The delay time, turn-on time, and jitter of alumina switch remained unchanged during <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\approx 105~000$ </tex-math></inline-formula> triggered discharges (@27.5 kV, 50- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Omega $ </tex-math></inline-formula> load, 60 Hz). The optimum operating mode of the switch is determined from the experimental results.