Performance Evaluation of PV Integrated DC-DC Converter with Load Demand, Irradiance, and Temperature Variations

Mostly, photo voltaic (PV) panels are operated with integration of dc-dc power converter, whose duty ratio is controlled to track the instantaneous maximum power point of the PV source. With an uncertain variation of the shading on the PV modules/strings during the time of peak load demand, there is a need to study the variations of the duty ratio of the DC-DC converter connected between the source and the load, to maintain the desired terminal voltage for a grid-connected PV system. The present study proposes an approach for the determination of DC-DC converter duty-ratio with variation in the load demand, irradiance and weather temperature. The studied approach has been implemented for a PV system with standard PV module models. The duty-ratio of the DC-DC converter for maximum PowerPoint has been obtained without shading, uniform shading, and non-uniform shading cases. Simultaneous MPP duty-ratio values and three-dimensional plots for variation in the load demand and the irradiance have been presented. The results obtained are very useful for the proper design of the DC-DC converter.