Highly efficient distributed MPPT architecture driven by α − β algorithm for partially shaded PV modules

A modern Maximum Power Point Tracking (MPPT) method based on the incremental conductance (IncCond) control algorithm is discussed. This method features a variable step iteration of duty ratio in order to get over the trade-off between dynamic performance and steady state oscillation around maximum power point (MPP). This is done through an MPP pass-through detection α and an acceleration mechanism β. Besides, a full stability test of the DC-DC power converter transfer functions is carried out using the Z-transform and has shown satisfactory results. Moreover, and since partially shaded series-connected PV modules exhibit multiple power maxima due to their integrated bypass diodes, all the centralized MPP trackers with all the available optimizations cannot harvest the max power delivered by the total PV sources and hence, are considered as non cost-effective. From that point on, the authors propose a distributed architecture driven by an intelligent α − β MPPT-based algorithm.