Numerical and experimental design of vacuum three-electrode spark gap for synthetic test circuits

The development of vacuum three-electrode spark gap used with a synthetic test circuit is considered in this paper. Two types of three-electrode vacuum insulated spark gaps have been tested: a spark gap with a third electrode being inside the main electrode, and a spark gap with a separate third electrode. Both types of spark gaps were theoretically sized in the optimal way. Testing of the numerical design of the spark gap was carried out experimentally. Three electrode materials were used: copper, steel and tungsten. The spark gap switching time and delay time are measured.