Design Analysis and Experimentation of High step up, High efficiency Isolated SEPIC Converter [articol]

Abstract

Due to energy crisis in the world the sources of renewable energy sources (RES) have to be enhanced. Out all RES, solar plays a main role. In photovoltaic (PV) power generation system, the dc to dc converter is unavoidable and which are prerequisite the high voltage gain conversion. Out of all converter topologies, SEPIC is a straight forward converter which can give high step continuous conduction operation. The SEPIC has a full degree of freedom to boost the voltage at 200%. Nevertheless high voltage gain is not possible, which is highly needed for PV based power electronics system. This high step voltage gain is possible only when transformer is converter circuit and through that the ratio of the inductance is increased and achieved maximum voltage gain. With this voltage gain improvement, the paper proposed a transformer connected modified SEPIC converter with high voltage gain degree of freedom. The proposed converter able to work for continuous current conduction mode since it is highly recommended for any converter to supply current to the load continuously and these converters are not affecting with switching frequency. The proposed converters different modes operation and it’s deign studies is clearly explained. The MATLAB based simulation studies for 1kW. The PIC microcontroller based 100W experimental test bench is developed and results are verified.