Progress on gyrotrons foriterand future thermonuclear fusion reactors

摘要

The prototype of the Japan 170 GHz ITER gyrotron holds the energy world record of 2.88 GJ (0.8 MW, 3600 s and 1 MW, 800 s) and the efficiency record of 57%. The Russian 170 GHz ITER prototype tube achieved 0.65 MW with a pulse duration of 800 s and 1.05 MW in 200 s pulses with an efficiency of 52%. The record parameters of the European megawatt-class 140 GHz gyrotron for the Stellarator Wendelstein W7-X are: 0.92 MW output power at 1800 s pulse duration, nearly 45% efficiency and 97.5% Gaussian mode purity. A similar 140 GHz CPI gyrotron has a somewhat lower efficiency. These gyrotrons employ a cylindrical cavity, a quasi-optical output coupler, a synthetic diamond window and a single-stage depressed collector (SDC) for energy recovery.