Test model of the fast thyristor circuit breaker for TORE SUPRA

The Tokamak TORE SUPRA, permits , owing to the toroidal superconducting coils and to the poloidal field system performances, to realize long discharges (30 s and more), for a plasma current of typically 2 MA. The poloidal field system uses the magnetic energy initially stored, for the ignition and the fast rise of the plasma current, by forcing the primary current to flow through a resistor after breaking the main rectifier current by a fast thyristor circuit breaker. In order to test the technical capabilities of such a breaker system made of fast thyristors, in series and in parallel, after a single thyristor test model T1, the series arrangement was studied on a 24 thyristor test model T2, and the parallel arrangement problems, led the manufacturer CGEE Alsthom, to build a new test model T3