Development of high power coaxial DC break for EAST ICRH system

Experimental Advanced Superconducting Tokamak (EAST) is a new experiment equipment for doing controlled nuclear fusion research in China and Ion Cyclotron Wave Resonant Heating (ICRH) is one of the most important methods to heat plasma in this equipment. In the ICRH system, the transmitter and the antenna both have their ground, which will severely perturb the system normal working. In order to ensure the system normal working, the coaxial DC (direct current) break is used to isolate the liner to which the transmitter is connected from the liner to which the antenna is connected, so the ground loop have been isolated then the system is working. In the paper, the design principle, engineering structure and design index have been presented, the calculation and simulation of the microwave network and port VSWR parameters have been analyzed, the actual measurement results are also given. (authors)