2.3: Reliability test of the ITER 170GHz gyrotron and development of the two-frequency gyrotron

Reliability of the 170 GHz ITER gyrotron is tested in JAEA. The 800 kW/600 sec pulse with 52-57% efficiency is repeated with interval of 20 min in 8 days. The 72 shots of 600 sec were successfully achieved out of 88 shots. The success rate was 82 %. It shows the realistic reliability for the gyrotron operation for ITER. The next step is a development of a multi frequency gyrotron. Preliminary test of the two-frequency gyrotron is performed. The 170 GHz and 136 GHz oscillations are successfully attained at short pulse (0.5 ms) and long pulse (10 sec). In the short pulse experiments, the maximum power of 1.3 MW is obtained at both frequencies.