Enhanced Z-source inverters

With a unique X-shaped LC network connected between its dc power source and inverter topology, a Z-source inverter can gain buck-boost ability and improve the reliability utilizing the shoot-through states which cannot be realized by a traditional inverter. However, the boosting capability of traditional Z-source inverter is limited and not be suitable for applications requiring very high boost inversion ability. An enhanced Z-source inverter topology with strong voltage boost inversion ability was proposed to expand the scope of application. Only a short shoot-through interval is required to obtain high voltage conversion ratios, so the modulation factor can be higher, which is conductive to improve the output power quality. Further more, the Z-source capacitor voltage stress is reduced greatly and thus can help to reduce the system cost and volume. The topology was analyzed in steady state, and simulation and experimental results were presented to validate the performances of the enhanced topology.