Repetitive Series Interrupter II

Abstract : The interruption characteristics have been established for six developmental 'plasma chute' interrupters, five rated at 15 kV and one rated at 30 kV. Six-hundred ampere interruptions at 20 kV have been achieved with a magnetic field energy of less than 8 joules. The most efficient interaction channel geometry has been found to be one which contains both a 'chuted' surface against which the discharge is magnetically driven, and an unchuted (smooth) surface located behind the driven discharge, the presence of which latter surface minimizes the availability of plasma to sustain the discharge. Typical interaction column drops have been found to be 300 to 400 volts per section (20 to 26 volts/cm) at reasonable tube pressures with no more than three (and possibly two) sections being adequate for the operation of tubes rated at 50 kV. Holdoff-section voltage drops of about 120 volts have been observed for holdoff sections capable of withstanding 30 kV. A total tube drop of 830 volts has been observed at the 25 kV, 18.5 A level. Linear extrapolation of existing data to the 50 kV, 1000 A level shows that reliable interruption should be achievable with a magnetic field energy of the order of 10 joules for an interrupter having a total tube drop of about 1200 volts, or 2.4% of the system's operating voltage.