35 Years of TF Magnet System Operation in Tore Supra-WEST: Status and Lessons Learnt

The 500 MJ superconducting toroidal field magnet of TORE SUPRA-WEST has been providing a 4 T magnetic field on the tokamak plasma axis since 1988. The magnet is bath-cooled with superfluid helium at 1.8 K, and operates in steady state each experimental day. During those years, the magnet internal structure has not been modified, but several interfaces and auxiliary systems required for its operation have been upgraded. This paper aims at giving an overview of the Tore Supra-WEST toroidal field magnet system. Main issues and upgrades are described while providing the community a valuable long-life operation feedback and return on experience. We will go through the normal operation sequences and the incidental events, trying to point out key components failures and recovery actions undertaken. We will also develop the main subsystems evolutions such as the quench protection system, the data acquisition and the control systems. We will outline the major risks and mitigation schemes followed as well as the strategies adopted to ensure adequate maintenance, to preserve skills and knowledge continuity over such a long and eventful operating time-frame.