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Tore Supra


CEA (Atomic Energy and Alternative Energy Commission) is a French government funded research organisation dedicated to the fields of energy, defense and security, information technologies and health technologies. It conducts fundamental and applied research into the design of nuclear reactors.


Tore Supra is a French tokamak that began operation following the discontinuation of TFR (Tokamak of Fontenay-aux-Roses) and of Petula (in Grenoble). It is situated at Cadarache which is one of the 10 research centres of the French Alternative Energies and Atomic Energy Commission (CEA).
The project’s objective is to create long-duration plasma. Tore Supra allows researchers to test critical parts of equipment such as plasma facing wall components or superconducting magnets.

One of the main Tore Supra objectives is to produce long and high performance discharges. In the frame of the CIMES project, associated with the manufacture of an ITER relevant PAM launcher, a new klystron was required from Thales to upgrade the power injection system and go above and beyond state of the art C band CW RF power for fusion applications.



Thales developed the TH 2103C in conjunction with French atomic energy commission CEA to further improve the Tore Supra’s power injection capability.

TH 2103C is a high-power klystron amplifier, delivering output power of more than 700 kW CW on a VSWR up to 1.4 during 1000 seconds. It operates at 3.7 GHz with a typical gain of 50 dB. Ideally suited for CW LHCD (Low Hybrid Current Drive) experiments, this klystron can be operated with a focusing magnet and RF combiner.

The development of this klystron started in 2001 and has been followed by the production of 18 series tubes.


The upgrade and installation of 16 tubes lead to an installed power of 12 MW in the lower hybrid transmitter.

These tubes have contributed to record-setting performances by the Tore Supra Tokamak such as:
the power record of 1 gigajoule injected and extracted,
the longest plasma duration time ever achieved by a tokamak - 6 minutes 30 seconds.