Cascaded TZ-source inverters

A new cascaded TZ-source inverter is proposed to distribute the stresses on the passive components. Compared with the conventional cascaded Z-source inverter topologies for the same number of transformers and turn ratios, the proposed cascaded inverter uses a high modulation index to produce the same output voltage gain with reduced component count. The inductor and transformer in the network can be combined in the proposed cascaded inverter. Its input current is continuous with low ripple if the DC source is connected directly to the inductor. The operating principles and an analysis of the cascaded TZ-source inverter are presented, and the proposed inverter is compared with the conventional cascaded Z-source inverters. Simulation and experiment are conducted with cascaded two-network and three-network TZ-source inverters to produce the same output voltage gain.