Design and testing of a rotary arc gap-switch for pulsed power

One of the key issues in pulsed power generation and its application is switch technology. The switches are divided into two categories of opening and closing switches. The most popular closing switches to date are spark-gap switches. The closing switches have a very limited lifetime due to arc corrosion resulting from the pinch effect and localized arc heating [Hare et al. (1975)]. Electrode phenomena in high-current carrying switch and transient phases in intense arcing modes are presented in papers by Prucker and Christiansen (1977) and Lehr et al. (1987). To extend the switch lifetime by minimizing electrode-vaporization, rotary arc gap-switches are investigated in papers by Kumar and Pramanik (1995), Desaulniers-Soucy and Meunier (1995), Gulie and Sloot (1975), and Yasko (1969). In those switches, rotation of the arc can be achieved by providing a rotating magnetic field from outside or by a self-induced magnetic field. Extensive experimental and theoretical investigations on arc characteristics and arc velocities in ring-type spark gaps are reported in papers by Gulie and Sloot (1975) and Yasko (1969). This paper investigates a rotating arc gap (RAG) switch driven by self-induced magnetic field. The physical dimensions, rotating arc speed, arc voltage drop, and its experimental setup are described in detail