A Simple Technique for the Global Power Peak Tracking in Partially Shaded Solar Systems

Partial shading has been shown to negatively affect the power output of solar PV systems. It occurs when part of a PV system is shaded while the rest of the system is fully illuminated. Partial shading disturbs the regular shape of the power curve that has single-power peak and produces power curve with multiple power peaks. Numerous hill-climbing algorithms exist, however they usually miss the operation on the global power peak and instead get stuck in one of the local peaks resulting in power losses. This paper derives a set of simple equations estimating the power peaks of partially shaded modules which are then utilized to develop a method for global power peak tracking. Unlike existing approaches, the proposed approach is very simple for implementation and does not require intricate models or special functions. Extensive verifications and validations are provided through simulations and experimentally. The results show that the proposed method can increase the power generation of solar PV systems through ensuring the global power peak extraction.