This paper presents a new single-phase multi-port DC–AC converter with
high voltage gain in low duty cycle. The operation of the proposed converter
consists of four modes, especially battery-alone mode, which makes it appropriate for stand-alone renewable applications. Using a suitable boosting
method, this converter can achieve high voltage gain in all modes. The high
gain performance of the converter occurs at both low shoot-through duty
cycle and high modulation index. Therefore, the output voltage and current
harmonics as well as the filter size are reduced. In addition, the converter
transfers the power with a continuous current through its input ports and
has a common ground between the input sources and the inverter bridge.
The positive features of this converter are the result of the appropriate
design and localization of the bidirectional port that connects the battery to
the converter. The proposed configuration includes an impedance network
that protects the converter in the shoot-through states and takes the
advantage of the shoot through in its boosting performance. Another
advantage of the proposed converter is that the voltage stress on the power
switches on the DC side is considerably low. In order to validate the feasibility and effectiveness of the converter, a prototype rated at 110 V is prepared
and tested.