Solid state transformer with low-voltage ride-through and current unbalance management capabilities

The solid state transformer is an emerging technology which aims at replacing the conventional low-frequency power transformer by means of a high-frequency transformer driven by a proper AC/AC power electronics conversion system, at both transformer sides. In comparison with the conventional power transformer, the solid state transformer provides extended and enhanced operating capabilities that can be achieved with an appropriate controller design for the power electronics converters. In this work, the interaction of the solid state transformer with a distribution system is analyzed under different operating conditions. Bidirectional active power flow, full reactive power control, low-voltage side current unbalance management and high-voltage side low-voltage ride-through are achieved with the proposed control approach.