Electromagnetic design of a short-circuiting system for one toroidal gap of the RFX shell

A short-circuiting system for the RFX shell has been designed in order to reduce the stray magnetic field at one toroidal gap. Several constraints imposed a solution consisting of 96 bars, whose effectiveness had to be verified. FEM electromagnetic analyses were carried out for this and the system performances were assessed. The main choices of the analyses and the results are reported and discussed in the paper. Some of the results were confirmed by direct measurements on the device.