Design of the Vacuum Feedthrough for the EAST ICRF Antenna

Detailed design of the vacuum feedthrough for the ion cyclotron radio frequency (ICRF) antenna in EAST, along with an electro-analysis and thermal structural analysis, is presented. The electric field, the voltage standing wave ratio (VSWR) and the stresses in the vacuum feedthrough are studied. A method using the rings of oxygen-free copper as the cushion and macro-beam plasma arc welding is applied in the assembly to protect the ceramic from being damaged during welding. The vacuum leak test on the prototype of vacuum feedthrough is introduced.