Repetitive Operation and Insulation Recovery Characteristics of a Sealed-off Double-gap Pseudospark Switch

Repetitive operation and insulation recovery characteristics of a sealed-off double-gap pseudospark switch have been experimentally investigated in this paper. The influence of hydrogen heater current is emphasized, and the results are analyzed from the discharge waveforms. As the heater current increases, the values of self-breakdown voltage and trigger delay decrease. In a relatively wide range of heater current, the hold-off voltage is higher than 50 kV, and the trigger jitter is below 3 ns. The minimum jitter is smaller than 1 ns. The direct repetitive operation of 2 kHz is achieved at the 15 kV anode voltage and the 1 kA current amplitude. Tests of higher repetition rate cannot be achieved due to the limitation of the charging circuit and trigger system. According to double-pulse tests, the insulation recovery speed is higher at lower heater current. As the time delay between two pulses increases, the second pulse breakdown voltage increases nonlinearly, and the insulation recovery curve shows different features from high-pressure switches. The maximum repetition rate can be higher than 8kHz for 40 kV pulsed voltage.