Fault Analysis of DC-Transformer for DC Distribution grid

The DC transformer (DCT) is a device that realizes energy interconnection and electrical isolation between different voltage levels in a DC distribution network. The stable operation of DCT directly affects the reliability of the DC distribution network. This paper studies the relay protection of the isolated DC transformer with Double Active Bridge(DAB). According to the actual situation, build the model in Matlab/Simulink. Considering various faults in the DAB, base on the study of fault characteristics, the protection area of the DC transformer is partitioned and equipped with a reliable relay protection principle.