Multi-input transformer coupled DC-DC converter for PV-wind based stand-alone single-phase power generating system

Hybrid PV-wind based stand-alone systems have evolved as a promising solution for rural deployment where access to electrification is not viable. The conventional approach for the integration of multiple renewable sources and energy storage elements involves using dedicated single-input converters for each source and requires more number of converter stages leading to considerable reduction in reliability and efficiency of the system. In order to address this issue, a novel transformer coupled dual-source dc-dc converter followed by a conventional full bridge inverter is proposed. Transformer coupled half-bridge boost converter is used for harnessing power from wind, while bidirectional converter is used for harnessing power from PV along with battery charging/discharging control and a single-phase inverter for feeding ac loads. The proposed converter architecture has reduced number of power conversion stages, less component count and losses as compared to the existing stand-alone schemes. These features improve the efficiency and reliability of the scheme. A suitable control strategy is proposed to operate the proposed converter in different modes. Analytical and simulation studies are carried out to ascertain the viability of the scheme.