A comparative analysis of non-isolated bi-directional dc-dc converters

Abstract

In this paper, five non-isolated bi-directional dc-dc converter topologies are analylized, demonstrated and design for the purpose of the renewable energy generation plants. These converters are: non-isolated bi-directional buck converter (NBBC), non-isolated bi-directional boost converter (NBOC), non-isolated bi-directional fly back converter (NBFC), non-isolated bi-directional CUK converter (NBCC) and non-isolated bi-directional SEPIC converter (NBSC).In the renewable energy sources like PV and wind, wide input voltage variation due to the temperature and environmental conditions. Besides, production of renewable has been very less since it came in the field of power generation. Non-isolated dc-dc converters are suitable for low voltage range and it's fit for the dc micro grid voltage level. Moreover, either load side or source side get sporadic current in the primitive dc-dc converters and output voltage is negative with respect to the ground in CUK converter. Aforementioned problems are rectified by the non-isolated bi-directional SEPIC converter (NBSC). Items such as ideal efficiency, ripple factor of voltage, ripple factor of current, size and sophistication are calculated for them. On the other hand, their output current and voltages are obtained by the simulation with PSCAD software. A comprehensive comparison is done among these converter topologies on the basics of above mentioned items. It is found that non-isolated bi-directional SEPIC converter is best suited for the non-conventional energy generation plants.