A model for the simulation of energy gains when using distributed maximum power point tracking (DMPPT) in photovoltaic arrays

Abstract

Over the past years, the photovoltaic (PV) market has been invaded with numerous power optimizers and micro-inverters that claim large energy gains when used in PV generators with shading or module mismatch. These products provide distributed maximum power point tracking (DMPPT), normally at module level, allowing the maximum power to be extracted from each PV module. This topology can be beneficial in situations where the PV generator is shaded or when there is large module mismatch. However, it is not clear that this power gain will result in energy improvements over a whole year or the lifetime of the system. This paper presents a very detailed and precise model for simulating energy gains with DMPPT as well as its verification and simulation results with different shading profiles, showing the possible energy gain over a whole year. Simulation results show that the yearly energy gain is much lower than the maximum power gain. However, interesting yearly gains of up to 12% are obtained in one of the simulations.