Techno-economical analysis for PV based water pumping system under partial shading/mismatching phenomena

Partial shading and/or mismatching phenomena in Photovoltaic (PV) based system cause reduced extraction of PV power and thus adversely impact the performance of PV based system; especially in case of stand-alone PV systems. In this paper four different configurations namely single stage PV system, centralized DC-DC converter based PV system, PV panel level Distributed maximum power point tracking (DMPPT) based PV system and PV module level DMPPT based PV system are considered for water pumping application. Impact of partial shading and mismatching for the considered four configurations is simulated using MATLAB/SIMLINK. Techno-economical analysis is performed in terms of PV power being extracted, saving in power and investment. From the analysis it is found that PV module level DMPPT based configuration is better in various types of random partial shading/mismatching conditions and increase in extracted PV power as compared to single stage and other configurations; justify the cost of additional investment required for additional DC-DC converters. Cost benefit analysis shows that even after considering the cost of additional DC-DC converters required to implement DMPPT PV module level, this method is more economical as it increases the utilization of installed PV capacity.