Post-fault operation of hybrid DC-DC converter for Solid-State Transformer

This paper presents a new topology of DC-DC converter with a post-fault operation ability for a Solid-State Transformer. It describes the concept of a Solid-State Transformer as a solution to improve flexibility and functionality of an electrical system. A conventional Solid-State Transformer is presented as well as a proposal for a modified topology based on a hybrid 3-phase Dual Active Bridge with high post-fault operation ability. The study of DC-DC converters takes into account well known topologies and the new proposed topology on which this paper is focused. Post-fault operation schemes are presented for both sides of DAB and for a Medium Voltage Converter, which is integral part interfacing DC-links with medium voltage grid. Simulation results confirm versatility of topology and ability to post-fault operation.