CRAFT TF Magnet Power Supply Overcurrent Protection Design

The overcurrent due to the short circuit of the thyristor arm is considered to be one of the important research contents. In the Comprehensive Research Facility for Fusion Technology (CRAFT) power supply system, when a short circuit occurs in the converter arm, the general protection method is to use a fuse for protection, but the way to select fuse is very blind, and the matching and suitability are not very good, resulting in a waste of components. In this paper, theoretical calculation and simulation verification are used for the CRAFT TF magnet power system, based on the principle of reliable fuse when the converter arm is short-circuited, and the principle of no action when the reactor is short-circuited, the fault current of the fast fuse is verified to determine the fast. The fuse model and the simulation results show that the selected fast fuse can effectively suppress the overcurrent, and the CRAFT tf magnet power system has been effectively protected.