DEVELOPMENT OF 170 GHZ 500 KW GYROTRON

A development of 170GHz/500kW level gyrotron was carried out as R&D wo rk of ITER. The oscillation mode is TE31,8. In a short pulse experimen t, the maximum power of 750kW was achieved at 85kV/40A. The efficiency was 22%. In the depressed collector operation, 500kW/36%/50ms was obt ained. The maximum efficiency of 40% was obtained at P-RF=470kW wherea s the power decrease by the electron trapping was observed. Pulse exte nsion was done up to 10s at P-RF=170kW with the depressed collector op eration. The power was limited by the temperature increase of the outp ut window.