The upgrade of the RFX fast protection system in view of the new operating scenarios and machine modification

This paper deals with the upgrade and the revision of the RFX fast protection system, which follow the recent modifications to the power supply circuits and the installation of a new copper shell and of 192 saddle coils for MHD mode control. The experimental evidences and the new requirements due to the machine and circuit modifications, which called for the revision of the system, are described, together with its new architecture.