Breakdown Research On EAST Tokamak

Breakdown was a basic research subject and it was important for operation the Tokamak especially for a whole superconducting Tokamak, ITER like, which was designed as integrative with all the coils.Enough high loop voltage and large null field region were necessary for the breakdown on EAST Tokamak. On EAST superconducting Tokamak, the poloidal field (PF) system was designed integrated, and there was no any compensated coil, so the high loop voltage and large null field region would be controlled with the current in PF coils carefully.This paper described the theory of plasma breakdown; establishing of the breakdown model on EAST Tokamak; the method to calculation mutual inductance coefficient; eddy current in the vacuum vessel; calculation the null field region and loop voltage. It was not only validates the model, but also directs the experiment, comparing the results of simulation with the data of the first EAST experiment. At last a Genetic Algorithms would be found to get a better breakdown condition for EAST.Many means would be used during the simulating process, such as Matlab Simulink; gridding calculate the mutual inductance coefficient; numerical method; the Eigen method; the symbol method; Simulink to calculate eddy current in the vacuum vessel; calculating the null field region and loop voltage, and so on.At last, this paper described the defect of this model and the method for improvement.