The development of mega-ampere contact structures for an electromagnetic launcher

The authors point out that electromagnetic launcher (railgun) development presents a challenging problem in electric contact design. The launcher requires mega-ampere peak currents with millisecond durations. The launcher segments require high-current joints capable of carrying the mega-ampere currents. High-current joints are also necessary to transfer the current from the distributed pulsed power capacitor banks to the railgun. Maintenance and repair of the railgun makes it necessary to disconnect the high-current joints. The evolution of the high-current contact design is discussed, and it is shown that the basic contact design criteria used for contact structures good over 100 kA can be extended to mega-ampere joints