Comparative Analysis of DC-DC Converters for Tracking MPP for Roof-Top PV Power Systems with and without Partial Shading Condition

This paper addresses comparative analysis between three basic converters i.e. Buck, Boost and Buck-Boost converter to interface with a rooftop domestic Photo-Voltaic (PV) system to track maximum power point (MPP) effectively in normal conditions and in partial shading conditions. With partial shading, variable atmospheric conditions and variable load, the working value of impedance at MPP (ZMPP) may vary widely. The MPPT algorithm should force the PV system work very near to ZMPP with the help of power electronic interface for varying load and atmospheric conditions in order to make the system work at MPP. The effectiveness of the MPPT algorithm and the power electronic interface can be inferred from this obligation. Although all the three mentioned DC-DC converters can be used as interface between PV source and desired load, the simulation study verifies that the performance of each converter is different. Here the effect of diverse load having different value than (ZMPP) on tracking MPP for both with and without partial shading condition is analyzed and it is deduced that Buck-Boost converter successfully tracks MPP for varying loading effect and atmospheric condition most efficiently.