A 500 kA repetitive opening switch

The performance of a 500 kA repetitive switch as part of railgun experiments at the Center for Electromechanical Research at the University of Texas is described. Switch performance was monitored during on-state, commutation, off-state and make phases of switching and in a post-mortem analysis of the rotor and collectors. A total of 84 high-current tests were conducted with the switch attached either to a railgun or a block of stainless steel. A peak commutated current of 303 kA was measured in initial tests of the switch. After refurbishment, a peak commutated current of 428 kA was observed but oscillations, which arose as a result of uneven soldering of collector leaves during reassembly, caused severe performance degradation and component damage.