A Matrix-Based Solid-State-Transformer For A Hybrid Nanogrid

This paper proposes a Front-end Matrix based Bidirectional Solid-State-Transformer (SST) for a nanogrid having both AC and DC power distribution networks. A single-phase Matrix-converter (MC) is used to convert the line-frequency grid voltage to High-Frequency AC (HFAC). The MC is modulated using a modified Sinusoidal-Pulse-Width Modulation (SPWM) scheme. The HFAC voltage is then fed to a Current-Doubler-Rectifier (CDR) to form a stiff Low-Voltage DC (LVDC) bus. A bidirectional-converter is used to facilitate energy interaction in between the AC and DC buses of the nanogrid. Simulation of the proposed SST scheme is performed and the results are presented to verify the theoretical analysis. A comparative analysis of the proposed topology with other relevant topologies is also presented. The proposed topology has comaparatively high reliability, exhibits high power density and superior input side power quality.