High-Power Gyrotron Development for Fusion Applications at KIT

In recent years Electron-Cyclotron-Resonance Heating and Current Drive (ECRH&CD) has been established as a preferable auxiliary heating system for magnetically confined nuclear fusion plasmas. ECRH&CD is successfully applied in tokamaks and helical machines for plasma start-up, heating, current drive, plasma control and suppression of instabilities.
Current EC systems are powered by gyrotrons operating in the frequency range of 77 – 170 GHz with a state-of-the-art power of 1 MW per unit. Future machines will definitely require increased RF tube output power with possibly increased frequency. To accommodate this development KIT is following two development lines: (i) the conventional, hollow cavity gyrotron and (ii) the coaxial cavity gyrotron.
Due to the successful operation of the W7-X stellarator IPP Greifswald decided to upgrade the gyrotron unit power from 1 to 1.5 MW. In a common project KIT is leading the design of the 1.5 MW, 140 GHz gyrotron.
Progress will be reported in the development of a 170 GHz, 1 MW gyrotron for ITER in the frame of a European collaboration, the experimental results of a short pulse gyrotron will be discussed. ... mehr
A short-pulse modular 170 GHz, 2 MW coaxial cavity gyrotron is equipped with advanced cooling systems to allow a pulse extension up to approximately 100 ms in a first step. In parallel, the design of the magnetron injection gun (MIG) has been significantly revised and an inverse MIG has been designed and manufactured.