Evaluation of Techniques to Reduce the Effects of Partial Shading on Photovoltaic Arrays

Shading is a harmful effect that decreases the power output of photovoltaic arrays. It can be observed that only a single shaded module is able to drastically reduce the energy production of the photovoltaic array. In addition, when shading reaches a larger number of modules, it becomes even more necessary to use techniques to reduce this effect, because in a series association the less efficient module limits the string current. This paper presents an analysis of six techniques that aim to reduce energy losses in photovoltaic panels operating under partial shading conditions. The techniques are evaluated through computer simulations, with the aid of PSIM^® software. Therefore, a comparison is made between these techniques, defining which is the most suitable for each shading profile.