Development of key ITER relevant technologies on the Tore Supra tokamak

As the largest superconducting tokamak presently in operation, with all plasma facing components (PFC) actively cooled, Tore Supra is able to routinely address critical issues of high power long duration discharges. Twenty years of operation of Tore Supra have been valorised through “lessons learnt” studies on systems critical for long pulse operation. Real time feedback systems have been developed to safely operate at a high level (>10 MW) of injected power. The versatility of the integrated plasma controller has allowed extending feedbacks to plasma performance optimisation. A dedicated long discharges campaign, cumulating 5 h of plasma in 10 operation days without any conditioning procedure meanwhile, has allowed to gain new insights in deuterium retention studies and to reveal a new operational limit characterised by a progressive decreases of the power handling capability. A strong development effort has been undertaken to follow up the PFC ageing during and between experimental campaigns. This includes the development of an articulated inspection arm, of lock-in thermography and confocal microscopy techniques. An important part of the Tore Supra programme, is the development of reliable heating and current drive systems. Progress in the development of lower hybrid couplers, klystrons and test of a load resilient ion cyclotron range of frequency are reported.