A new bidirectional isolated converter for grid connection

This paper proposes a bidirectional isolated AC-AC converter for grid connection of various loads or energy sources. The converters can be utilized for interfacing renewable energy sources to the grid as well as traditional motor drives. It does not employ any line-frequency transformer, large electrolytic capacitors, and inductors to diminish the volume and enhance the reliability of the converter. Instead, it uses high-frequency transformers and small film capacitors. Also, Because of its modular structure, it can be extended easily according to the system voltage. Its configuration and the concept of power flow are introduced and the simulation results are presented.