Improvement of the gyrotron TH 1506B for Tore Supra [Tokamak application]

For heating and current drive experiments by electron cyclotron resonance interaction on the Tore Supra Tokamak, an ECRH system with a generator power of 2.4 MW (3 MW) for a pulse duration of 210 s (5 s) at a frequency of 118 GHz is presently under construction at CEA Cadarache. The generator is made of six TH 1506B gyrotrons. The main design parameters of the gyrotron are given in this paper. Prototype and first series gyrotrons are already installed on Tore Supra.