A single-stage forward inverter with high frequency isolation for grid-connected application

A single-stage inverter based on bi-directional forward converter with high frequency isolation for grid-connected application is proposed. The inverter is comprised of two improved bi-directional forward dc-dc converters, which are input-parallel and output-series (IPOS) connected. Each bidirectional dc-dc converter has two secondary rectifiers in series and the voltage stress on the freewheeling switches is halved. The operational principle of the inverter is given with transformer reset and voltage stress analyzed in details. Experimental results are presented to verify the validity and feasibility of the proposed single-stage inverter.