MV multi channel closing switch for water storages

As a start point for the authors´ development in MV closing switches, the Sandia Rimfire switch was chosen that was successfully proved in different installations over a long period of time. This gas switch consists of a stack of intermediate electrodes that form a self breakdown section, connected in series with a trigger gap. The voltage across the self breakdown section relates to that of the trigger gap as /spl sim/3:1. The switch is triggered by closing the trigger gap resulting in overvoltage in the self breakdown section. After the gas gaps in this section break down the whole discharge current flows in multiple channels in self breakdown section and through the single spark in the trigger gap. In this paper, the authors present the design of several switch modifications and the results of the experiments on a testbed with 2.3 MV output voltage. On the given step of the work, the main goal was to prove the multi channel discharge along the whole length of the switch. The problems related to the switch body flashover were also considered but they will be the main goal of future work in this field.