Non-arcing commutation in explosive opening switches

Abstract

Explosively actuated opening switches can develop high impedance without arcing. In this paper we examine the commutation performance of the RAP switch in the Air Force Armament Technology Battery Power System. The Battery Power System stores over 10 MJ at up to 2.5 MA in an inductor. The RAP switch is used to commutate tlie current into a railgun load. The RAP switch develops several hundred volts before it completely opens and arcs. We have developed an analytic description of the non-arcing opening powers and we show that it is primarily resistive and that current diffusion plays a central role. Experimental results which validate the theoretical model are also presented. Finally, we show how the affect can be exploited to achieve higher non-arcing impedance thereby reducing the destructive effects of arcs on the opening switch.

Predicted versus actual performance of the model scale compulsator system

“…Quite a bit of effort was expended to understand the rail gun and armature interactions and their effects on projectile performance [9,10,11]. In addition, some attention was paid to mechanical opening and closing switches [12,13]. However, the pulsed power supplies in these early systems were largely static capacitor banks or inductor arrays.…”