Improved trans-current-fed switched inverter

摘要

Very high voltage boost is an essential requirement for connecting small voltage renewable sources to the standalone residential system or to the grid. Current-Fed Switched Inverter (CFSI) can provide a very high boost utilizing the shoot through of its inverter legs. Apart from high boost, CFSI also offers continuous input current and low passive component count which makes it suitable for renewable applications. Coupled inductor based topologies found in the literature provides increased gain at the expense of increased coupled inductor turns ratio. This paper presents a novel coupled inductor based CFSI topology in which higher gain is achieved by lowering the coupled inductor turns ratio (n), unlike other coupled/tapped inductor topologies. The proposed inverter, named Improved Trans-Current Fed Switched Inverter (Improved Trans-CFSI), offers higher gain with smaller coupled inductor turns ratio, which is a major improvement over the other coupled inductor based high boost inverter topologies where higher turns ratio is required to achieve higher gain. The paper presents the detailed steady-state analysis of the proposed inverter and establishes the relation between their input output parameters. The operation of the inverter is validated by the experimental results which show strong correlation with the theoretical analysis.