Trans-switched boost inverters

Conventional switched boost inverters (SBIs) employ a single LC-pair in the impedance network to boost the input voltage by setting a shoot-through interval in the inverter bridge switches. This study extends the concept of SBIs to the transformer-based switched boost inverters (trans-SBIs). By changing the turn ratio of the transformer, the proposed trans-SBIs can produce a strong voltage gain. Compared with a tapped-inductor Z-source inverter with the same voltage gain at the same transformer turn ratio, the proposed trans-SBIs have only one extra active switch but significantly fewer passive components. Compared with trans-ZSI, the proposed trans-SBIs use a transformer with a lower turn ratio to achieve a higher boost factor. The required current rating of the switches in the proposed trans-SBI is lower than for the alternative ZSIs. The operating principles and the analyses and comparisons with the conventional transformer-based ZSIs are presented. To verify the high boost capability of the proposed inverters, a laboratory prototype was built for both the single-phase and three-phase trans-SBIs.