(EX/1-6) Physics and operational integrated controls for steady state scenario
1) ASSOCIATION EURATOM-CEA sur la Fusion, Saint-Paul-lez-Durance, France
Abstract. Assembling the relevant physics features using integrated controls is expected to be a major challenge in the operation of ITER steady state scenario. In recent experimental campaigns, Tore Supra has therefore focused its efforts on the physics optimisation and operation of steady state scenario with high input power close to 7 MW and vanishing loop voltage (more than 90% of non-inductive current) with duration of typically 60 s and above. To use its long pulse capabilities Tore Supra has also been equipped with a large number of new real time systems. With these tools, the control of the LH deposition profile width measured by the Hard X-ray camera has been achieved with the parallel index and power of the LH-wave using different type of control algorithms. Temperature gradient has also been controlled during internal transport barriers and the effect of Electron Cyclotron Heating (ECH) on control assessed. Then, the control of the current profile with the parallel index has been achieved in combination with loop voltage control (at 60 mV) using the central solenoid voltage as actuator. The RF antennae are receiving power fluxes from their private power but also from the plasma convective power and large orbit fast ions generated by ICRH. On the basis of the experimental power load and hot spot analyses, the seven infra-red cameras monitoring the five antennae (2 LH-launchers and 3 ICRH antennae) and the bottom limiter have been used for real time protection and combined successfully to LH deposition profile and loop voltage control. These experiments and modelling are pioneering the integration work that will be required on ITER when combining physics requirements for achieving the requested plasma performances and machine technologic constraints.
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