Triggered vacuum gap that controllably sustains a vacuum arc through current zeros

A triggered vacuum gap (TVG) device comprising:

• an outer housing having an insulating wall, a first end cap at one end of the housing and a second end cap at an opposite end of the housing, the outer housing having an internal vacuum chamber;
• a first main electrode assembly including a first stem extending through the first end cap and into the vacuum chamber and a first main electrode attached to the first stem within the vacuum chamber, the first stem including a bore and the first main electrode including an opening;
• a first triggering electrode extending through the bore in the first stem and into the opening in the first main electrode, wherein a first triggering gap is defined between the first main electrode and the first triggering electrode;
• a second main electrode assembly including a second stem extending through the second end cap and into the vacuum chamber and a second main electrode attached to the second stem within the vacuum chamber, wherein a main gap is defined in the vacuum chamber between the first and second main electrodes;
• and
• a first triggering circuit for energizing the first main electrode and the first triggering electrode, the first triggering circuit including a first high voltage impulse source that supplies a fast rising high voltage impulse to the first main electrode and the first triggering electrode for creation of a plasma to provide an initial breakdown of the first triggering gap and breakdown of the main gap and a first low voltage unidirectional current source, which includes a first capacitor and a second capacitor that are both simultaneously discharged to supply the current to the first main electrode and the first triggering electrode for a specified duration once the first triggering gap breakdown has occurred.