Reignition development in short vacuum gaps after interruption of high-frequency currents

Very high and steep overvoltages can be produced during the reignitions of switching devices after interrupting high-frequency currents. The mechanism of such reignitions is studied in this paper experimentally by considering the light intensity emitted from the vacuum gap during a reignition. The emitted light intensity is recorded by a streak-camera. The recorded light intensities show that an emission center building at the cathode surface precedes the breakdown of the vacuum gap. This result corresponds to the simulation results of the breakdown development of short vacuum gaps presented in earlier works.