Transformer based Z-source inverters have attracted more attention recently due to the advantages of reduced component count and its maximized use of the modulation index. In this paper, a new type of dual transformer based Z-source inverter is proposed. It uses two -source networks mirroring each other to form the sigma network. The proposed topology has the advantage of increasing the input to output voltage gain by reducing the turn ratio resulting in a smaller transformer for high voltage gain applications. The operating principle, simulation results and experimental work are presented.