A Metallic Contact, Fast Closing, High-Current Switch

Abstract

The proposed fast-discharge experiment (FDX) to be conducted on a special homopolar machine by the Center for Electro-Mechanics at the University of Texas requires for current initiation a making switch capable of carrying close to 2 106 A with an extremely fast rise time in the order of 2.9 10 9 A/s. This rate of rise precludes a conventional making switch. The solution chosen uses electromagnetic repulsion to drive a movable contact which in the closed position metallically bridges two stationary electrodes. Once closed, the device has very small internal resistance and a minimum of inductance. The design is described, the application in the FOX experiments is shown and the predicted performance is compared with actual test results.Center for Electromechanic