Step-size fuzzy control to maximum power point tracking algorithms for PV microgrid arrays

Photo Voltaic (PV) power generation presents a high potential solution to the emerging energy needs and the pollution levels crisis around the world. PV cells have associated current-voltage nonlinear characteristics which vary according to irradiance levels, load impedance and temperature mainly. Maximum Power Point Tracking (MPPT) algorithms are relevant elements in economically viable PV systems. They seek to obtain all the available power from PV modules under every environmental condition. Perturb and Observe (P&O) and Incremental Conductance (IC) are well known MPPT algorithms that are commonly used. This paper proposes an improvement to these methods based on the adaptability under nonlinear conditions, and simplicity of Fuzzy Logic Control (FLC). The detailed design and the applicability in smart microgrids and distributed generation are presented. Comparison simulation results show a faster and adaptable behaviour of the fuzzy controlled algorithms developed.