A New Method for Current Distribution Study in the 6-in IGCT

With the rapid development of the DC grids, the DC circuit breakers, especially the hybrid type, play an essential role in the operation of the whole system. The 6-in IGCT with 12.5kA current cut-off capability is promising for the hybrid DC breaker. However, the further improvement of current cut-off capability is restricted by the comprehension of the failure mechanisms. Based on this, a new method for current distribution study in the 6-in IGCT is proposed with a special package. Inductance simulation with finite element methods reveals that the stray inductance of the new structure is extremely similar to the traditional one. Finally the current information of different areas is obtained with this new structure in IGCT’s safe operating area. The results can not only display the commutating process clearly, but also show that the pressure distribution in the 6-in IGCT tends to be uneven, leading to current crowding in high-pressure areas due to low contact resistances.